Sample records for density polyurethane foam

  1. Properties of rigid polyurethane foams filled with glass microspheres

    NASA Astrophysics Data System (ADS)

    Yakushin, V.; Bel'kova, L.; Sevastyanova, I.

    2012-11-01

    The effect of hollow glass microspheres with a density of 125 kg/m3 on the properties of low-density (54-90 kg/m3) rigid polyurethane foams is investigated. The thermal expansion coefficient of the foams and their properties in tension and compression in relation to the content of the microspheres (0.5-5 wt.%) are determined. An increase in the characteristics of the material in compression in the foam rise direction with increasing content of filler is revealed. The limiting content of the microspheres above which the mechanical characteristics of the filled foams begin to decrease is found. The distribution of the microspheres in elements of the cellular structure of the polyurethane foams is examined.

  2. Study of factors influencing the mechanical properties of polyurethane foams under dynamic compression

    NASA Astrophysics Data System (ADS)

    Linul, E.; Marsavina, L.; Voiconi, T.; Sadowski, T.

    2013-07-01

    Effect of density, loading rate, material orientation and temperature on dynamic compression behavior of rigid polyurethane foams are investigated in this paper. These parameters have a very important role, taking into account that foams are used as packing materials or dampers which require high energy impact absorption. The experimental study was carried out on closed-cell rigid polyurethane (PUR) foam specimens of different densities (100, 160 respectively 300 kg/m3), having a cubic shape. The specimens were subjected to uniaxial dynamic compression with loading rate in range of 1.37-3.25 m/s, using four different temperatures (20, 60, 90, 110°C) and two loading planes (direction (3) - rise direction and direction (2) - in plane). Experimental results show that Young's modulus, yield stress and plateau stress values increases with increasing density. One of the most significant effects of mechanical properties in dynamic compression of rigid PUR foams is the density, but also the loading speed, material orientation and temperature influences the behavior in compression

  3. Open-celled polyurethane foam

    NASA Technical Reports Server (NTRS)

    Russell, L. W.

    1970-01-01

    Open-celled polyurethane foam has a density of 8.3 pounds per cubic foot and a compressive strength of 295 to 325 psi. It is useful as a porous spacer in layered insulation and as an insulation material in vacuum tight systems.

  4. Physicomechanical Characteristics of Spray-On Rigid Polyurethane Foams at Normal and Low Temperatures

    NASA Astrophysics Data System (ADS)

    Yakushin, V. A.; Zhmud', N. P.; Stirna, U. K.

    2002-05-01

    The effect of processing factors on the inhomogeneity and physicomechanical characteristics of spray-on polyurethane foams is studied. The dependences of the basic characteristics of foam plastics on the apparent density and cell-shape factor are determined. A method is offered for evaluating the effect of the technological surface skin on the tensile characteristics of foam plastics under normal and low temperatures.

  5. Prototype Salvage Foaming System.

    DTIC Science & Technology

    1985-11-04

    providing buoyancy to refloat sunken ships, the density and strength of polyurethane foam , combined with its compact pre-blown form , make it a very...is not a true solvent of polyol and MDI, polyurethane foam can form in the presence of DOP. In the full-scale machine, the head flushing chemical is...hose between the foaming machine and foaming gun, standard grade hydraulic hose is used. This type of hose is also much more resistant to kinking than

  6. DOE Office of Scientific and Technical Information (OSTI.GOV)

    Hartman, E. Frederick; Zarick, Thomas Andrew; Sheridan, Timothy J.

    We performed measurements and analyses of the prompt radiation-induced conductivity (RIC) in thin samples of polyurethane foam and glass microballoon foam at the Little Mountain Medusa LINAC facility in Ogden, UT. The RIC coefficient was non-linear with dose rate for polyurethane foam; however, typical values at 1E11 rad(si)/s dose rate was measured as 0.8E-11 mho/m/rad/s for 5 lb./cu ft. foam and 0.3E-11 mho/m/rad/s for 10 lb./cu ft. density polyurethane foam. For encapsulated glass microballoons (GMB) the RIC coefficient was approximately 1E-15 mho/m/rad/s and was not a strong function of dose rate.

  7. Mechanical properties of palm oil based bio-polyurethane foam of free rise and various densities

    NASA Astrophysics Data System (ADS)

    Hilmi, Hazmi; Zainuddin, Firuz; Cheng, Teoh Siew; Lan, Du Ngoc Uy

    2017-12-01

    Bio-foam was produced from palm oil-based polyol (POBP) and methylene diphenyl diisocyanate (MDI) with weight ratio of 1:1. The effect of opened mould (as free rise) and closed mould (control expansion) was investigated. Different densities of bio-polyurethane foam (0.3, 0.4 and 0.5 g.cm-3) were prepared using the closed mould system. The effect of density on morphology and compressive properties of bio-foam was studied. Results showed that bio-foam prepared by closed mould method possessed homogeneous cell structure and cell size compared to bio-foam prepared by opened mould. In addition, bio-foam using closed mould system had higher compression strength (0.47 MPa) than that of bio-foam using opened mould system (0.13 MPa). With higher density and lesser porosity, the compressive modulus and compressive strength of bio foams will be higher. The increase in compressive properties is due to the decrease in the cells size, more homogeneous cell structure and reduction in porosity content.

  8. Temperature and speed of testing influence on the densification and recovery of polyurethane foams

    NASA Astrophysics Data System (ADS)

    Apostol, Dragoş Alexandru; Constantinescu, Dan Mihai

    2013-02-01

    Polyurethane foams with densities of 35, 93, and 200 kg/m3 were tested in compression at three levels of temperatures as: -60 °C, 23 °C, and 80 °C. The influence of speed of testing from 2 mm/min up to 6 m/s (0.0014 to 545 s-1) on the response of the foams is analyzed. Testing is done separately on the rise direction and on the in-plane direction of the foams, and differences in their behavior are commented. With interpolation functions which approximate the plateau and densification region, the specific strain energy is calculated together with the energy efficiency and onset strain of densification. A Nagy-type phenomenological strain-rate-dependent model is proposed to generate engineering stress-strain curves and is validated through comparison with experimental stress-strain curves obtained at different speeds of testing. Starting from a reference experimental curve, two material parameters which are density and temperature dependent are established. Foam recovery for each density of the polyurethane foams is analyzed as a function of direction of testing, temperature, and speed of testing.

  9. Cell openness manipulation of low density polyurethane foam for efficient sound absorption

    NASA Astrophysics Data System (ADS)

    Hyuk Park, Ju; Suh Minn, Kyung; Rae Lee, Hyeong; Hyun Yang, Sei; Bin Yu, Cheng; Yeol Pak, Seong; Sung Oh, Chi; Seok Song, Young; June Kang, Yeon; Ryoun Youn, Jae

    2017-10-01

    Satisfactory sound absorption using a low mass density foam is an intriguing desire for achieving high fuel efficiency of vehicles. This issue has been dealt with a microcellular geometry manipulation. In this study, we demonstrate the relationship between cell openness of polyurethane (PU) foam and sound absorption behaviors, both theoretically and experimentally. The objective of this work is to mitigate a threshold of mass density by rendering a sound absorber which shows a satisfactory performance. The cell openness, which causes the best sound absorption performance in all cases considered, was estimated as 15% by numerical simulation. Cell openness of PU foam was experimentally manipulated into desired ranges by adjusting rheological properties in a foaming reaction. Microcellular structures of the fabricated PU foams were observed and sound absorption coefficients were measured using a B&K impedance tube. The fabricated PU foam with the best cell openness showed better sound absorption performance than the foam with double mass density. We envisage that this study can help the manufacture of low mass density sound absorbing foams more efficiently and economically.

  10. Effect of Filler Type on the Properties of Rigid Polyurethane Foams at a Cryogenic Temperature

    NASA Astrophysics Data System (ADS)

    Yakushin, V.; Cabulis, U.; Sevastyanova, I.

    2015-09-01

    The effect of filler type and mass percentage on the properties of low-density rigid polyurethane foams at a temperature of 77K was investigated. The mechanical properties of foams of density 55-90 kg/m3 filled with milled carbon fibers of average length of 100 and 60 μm and hollow glass microspheres of average diameter of 65 μm were compared. A considerable increase in the compressive elastic modulus in the foam rise direction with increasing filler content was observed. The compression strength of the foams in the parallel and perpendicular directions at the cryogenic temperature decreased upon introducing the milled carbon fibers of either type. The compression strength of the foams of density 90 kg/m3 somewhat increased only upon introducing the glass microspheres.

  11. Assessment of Multiaxial Mechanical Response of Rigid Polyurethane Foams

    NASA Astrophysics Data System (ADS)

    Pettarin, Valeria; Fasce, Laura A.; Frontini, Patricia M.

    2014-02-01

    Multiaxial deformation behavior and failure surface of rigid polyurethane foams were determined using standard experimental facilities. Two commercial foams of different densities were assayed under uniaxial, biaxial, and triaxial stress states. These different stress states were reached in a uniaxial universal testing machine using suitable testing configurations which imply the use of special grips and lateral restricted samples. Actual strains were monitored with a video extensometer. Polyurethane foams exhibited typical isotropic brittle behavior, except under compressive loads where the response turned out to be ductile. A general failure surface in the stress space which accounts for density effects could be successfully generated. All of failure data, determined at the loss of linear elasticity point, collapsed in a single locus defined as the combination of a brittle crushing of closed-cell cellular materials criterion capped by an elastic buckling criterion.

  12. Some physical and mechanical properties of recycled polyurethane foam blends

    NASA Astrophysics Data System (ADS)

    Bledzki, A. K.; Zicans, J.; Merijs Meri, R.; Kardasz, D.

    2008-09-01

    Blends of secondary rigid polyurethane foams (RPUFs) with soft polyurethane foams (SPUFs) were investigated. The effect of SPUF content and its chemical nature on some physical and mechanical properties of the blends was evaluated. Owing to the stronger intermolecular interaction and higher values of cohesion energy, the blends of RPUFs with polyester SPUFs showed higher mechanical properties than those with polyether SPUFs. The density, hardness, ultimate strength, and the tensile, shear, and flexural moduli increased, while the impact toughness, ultimate elongation, and damping characteristics decreased with increasing RPUF content in the blends.

  13. Effect of silica nanoparticles on polyurethane foaming process and foam properties

    NASA Astrophysics Data System (ADS)

    Francés, A. B.; Navarro Bañón, M. V.

    2014-08-01

    Flexible polyurethane foams (FPUF) are commonly used as cushioning material in upholstered products made on several industrial sectors: furniture, automotive seating, bedding, etc. Polyurethane is a high molecular weight polymer based on the reaction between a hydroxyl group (polyol) and isocyanate. The density, flowability, compressive, tensile or shearing strength, the thermal and dimensional stability, combustibility, and other properties can be adjusted by the addition of several additives. Nanomaterials offer a wide range of possibilities to obtain nanocomposites with specific properties. The combination of FPUF with silica nanoparticles could develop nanocomposite materials with unique properties: improved mechanical and thermal properties, gas permeability, and fire retardancy. However, as silica particles are at least partially surface-terminated with Si-OH groups, it was suspected that the silica could interfere in the reaction of poyurethane formation.The objective of this study was to investigate the enhancement of thermal and mechanical properties of FPUF by the incorporation of different types of silica and determining the influence thereof during the foaming process. Flexible polyurethane foams with different loading mass fraction of silica nanoparticles (0-1% wt) and different types of silica (non treated and modified silica) were synthesized. PU/SiO2 nanocomposites were characterized by FTIR spectroscopy, TGA, and measurements of apparent density, resilience and determination of compression set. Addition of silica nanoparticles influences negatively in the density and compression set of the foams. However, resilience and thermal stability of the foams are improved. Silica nanoparticles do not affect to the chemical structure of the foams although they interfere in the blowing reaction.

  14. Study of Polyurethane Foaming Dynamics Using a Heat Flow Meter

    NASA Astrophysics Data System (ADS)

    Koniorczyk, P.; Trzyna, M.; Zmywaczyk, J.; Zygmunt, B.; Preiskorn, M.

    2017-05-01

    This work presents the results of the study concerning the effects of fillers addition on the heat flux density \\dot{q}( t ) of foaming of polyurethane-polystyrene porous composite (PSUR) and describes the dynamics of this process during the first 600 s. This foaming process resulted in obtaining porous materials that were based on HFC 365/225 blown rigid polyurethane foam (PUR) matrix, which contained thermoplastic expandable polystyrene (EPS) beads as the filler. In PSUR composites, the EPS beads were expanded after being heated to a temperature above the glass transition temperature of EPS and vaporing gas incorporated inside, by using the heat of exothermic reaction of polyol with isocyanate. From the start (t=0) to the end of the PSUR composite foaming process (t=tk), \\dot{q}( t ) was measured with the use of the heat flow meter. For the purpose of the study two PUR systems were selected: one with high and one with low heat density of foaming process q. EPS beads were selected from the same manufacturer with large and small diameter. The mass fraction of EPS in PSUR foam varied during the measurements. Additionally, a study of volume fractions of expanded EPS phase in PSUR foams as a function of mass fractions of EPS was conducted. In order to verify effects of the EPS addition on the heat flux density during PSUR foaming process, the thermal conductivity measurements were taken.

  15. Properties of rigid polyurethane foams filled with milled carbon fibers

    NASA Astrophysics Data System (ADS)

    Yakushin, V.; Stirna, U.; Bel'kova, L.; Deme, L.; Sevastyanova, I.

    2011-01-01

    The effect of milled carbon fibers of two types (differing in length) on the properties of rigid polyurethane foams in the density range from 50 to 90 kg/m3 is investigated. The coefficient of thermal expansion and properties of the foams in tension and compression as functions of fiber content in them are determined. It is found that the long fibers are more efficient in improving the properties of the foams in their rise direction. The elongation at break of the foams decreases significantly with increasing fiber content.

  16. Polyurethane foam with multi walled carbon nanotubes/magnesium hybrid filler

    NASA Astrophysics Data System (ADS)

    Adnan, Sinar Arzuria; Zainuddin, Firuz; Zaidi, Nur Hidayah Ahmad; Akil, Hazizan Md.; Ahmad, Sahrim

    2016-07-01

    The purpose of this paper is to investigate the effect of multiwalled carbon nanotubes (MWCNTs)/magnesium (Mg) hybrid filler in polyurethane (PU) foams with different weight percentages (0.5 wt.% to 3.0 wt.%). The PU/MWCNTs/Mg foam composites were formed by reaction of based palm oil polyol (POP) with methylene diphenyl diisocyanate (MDI) with ratio 1:1.1 by weight. The foam properties were evaluated in density, morphology and compressive strength. The addition of 2.5 wt.% hybrid filler showed the higher density in 59.72 kg/m3 and thus contribute to the highest compressive strength at 1.76 MPa. The morphology show cell in closed structure and addition hybrid filler showed uneven structure.

  17. Characterization of commercial rigid polyurethane foams used as bone analogs for implant testing.

    PubMed

    Calvert, Kayla L; Trumble, Kevin P; Webster, Thomas J; Kirkpatrick, Lynn A

    2010-05-01

    Mechanical properties and microstructure characterization of a series of graded commercial rigid polyurethane foams commonly used to mimic trabecular bone in testing orthopaedic devices is reported. Compressive testing conducted according to ASTM standard F1839-08, which requires large specimens (50.8 mm x 50.8 mm x 25.4 mm blocks) gave elastic modulus and compressive strength values ranging from 115 to 794 MPa and 4.7 to 24.7 MPa, respectively, for foams having densities of 0.240-0.641 g/cm(3). All these results were within the requirements of the specification for the corresponding grades. Compression testing using smaller specimens (7.5 mm diameter x 15 mm) typical of testing bone, gave results in good agreement with those obtained in the standard tests. Microstructural measurements showed the average pore size ranged from 125 to 234 microm for densities ranging from 0.641 to 0.159 g/cm(3), respectively. The relative modulus as a function of relative density of the foams fit well to the model of Gibson and Ashby. Cyclic testing revealed hysteresis in the lower density foams with a loading modulus statistically equivalent to that measured in monotonic testing. Shore DO durometry (hardness) measurements show good correlations to elastic modulus and compressive strength. The results suggest additional parameters to consider for the evaluation of polyurethane foams for bone analog applications.

  18. Method for providing a low density high strength polyurethane foam

    DOEpatents

    Whinnery, Jr., Leroy L.; Goods, Steven H.; Skala, Dawn M.; Henderson, Craig C.; Keifer, Patrick N.

    2013-06-18

    Disclosed is a method for making a polyurethane closed-cell foam material exhibiting a bulk density below 4 lbs/ft.sup.3 and high strength. The present embodiment uses the reaction product of a modified MDI and a sucrose/glycerine based polyether polyol resin wherein a small measured quantity of the polyol resin is "pre-reacted" with a larger quantity of the isocyanate in a defined ratio such that when the necessary remaining quantity of the polyol resin is added to the "pre-reacted" resin together with a tertiary amine catalyst and water as a blowing agent, the polymerization proceeds slowly enough to provide a stable foam body.

  19. A numerical study of shock wave reflections on low density foam

    NASA Astrophysics Data System (ADS)

    Baer, M. R.

    1992-06-01

    A continuum mixture theory is used to describe shock wave reflections on low density open-cell polyurethane foam. Numerical simulations are compared to the shock tube experiments of Skews (1991) and detailed wave fields are shown of a shock wave interacting with a layer of foam adjacent to a rigid wall boundary. These comparisons demonstrate that a continuum mixture theory describes well the shock interactions with low density foam.

  20. Polyurethane Foam Impact Experiments and Simulations

    NASA Astrophysics Data System (ADS)

    Kipp, M. E.; Chhabildas, L. C.; Reinhart, W. D.; Wong, M. K.

    1999-06-01

    Uniaxial strain impact experiments with a rigid polyurethane foam of nominal density 0.22g/cc are reported. A 6 mm thick foam impactor is mounted on the face of a projectile and impacts a thin (1 mm) target plate of aluminum or copper, on which the rear free surface velocity history is acquired with a VISAR. Impact velocities ranged from 300 to 1500 m/s. The velocity record monitors the initial shock from the foam transmitted through the target, followed by a reverberation within the target plate as the wave interacts with the compressed foam at the impact interface and the free recording surface. These one-dimensional uniaxial strain impact experiments were modeled using a traditional p-alpha porous material model for the distended polyurethane, which generally captured the motion imparted to the target by the foam. Some of the high frequency aspects of the data, reflecting the heterogeneous nature of the foam, can be recovered with computations of fully 3-dimensional explicit representations of this porous material.

  1. Efficient continuous dryer for flexible polyurethane foam and cleaning apparatus

    DOEpatents

    Jody, Bassam; Daniels, Edward; Libera, Joseph A.

    1999-01-01

    A method of cleaning polyurethane foams where the material is transported through a wash station while alternately soaking the polyurethane foam in an organic solvent and squeezing solvent from the polyurethane foam a number of times. Then the polyurethane foam is sent through a rinse or solvent transfer station for reducing the concentration of solvent in the foam. The rinsed polyurethane foam is sent to a drying station wherein the foam is repeatedly squeezed while being exposed to hot air to remove wet air from the foam.

  2. Efficient continuous dryer for flexible polyurethane foam and cleaning apparatus

    DOEpatents

    Jody, B.; Daniels, E.; Libera, J.A.

    1999-03-16

    A method of cleaning polyurethane foams where the material is transported through a wash station while alternately soaking the polyurethane foam in an organic solvent and squeezing solvent from the polyurethane foam a number of times. Then the polyurethane foam is sent through a rinse or solvent transfer station for reducing the concentration of solvent in the foam. The rinsed polyurethane foam is sent to a drying station wherein the foam is repeatedly squeezed while being exposed to hot air to remove wet air from the foam. 4 figs.

  3. Correlation between structure and compressive strength in a reticulated glass-reinforced hydroxyapatite foam.

    PubMed

    Callcut, S; Knowles, J C

    2002-05-01

    Glass-reinforced hydroxyapatite (HA) foams were produced using reticulated foam technology using a polyurethane template with two different pore size distributions. The mechanical properties were evaluated and the structure analyzed through density measurements, image analysis, X-ray diffraction (XRD) and scanning electron microscopy (SEM). For the mechanical properties, the use of a glass significantly improved the ultimate compressive strength (UCS) as did the use of a second coating. All the samples tested showed the classic three regions characteristic of an elastic brittle foam. From the density measurements, after application of a correction to compensate for the closed porosity, the bulk and apparent density showed a 1 : 1 correlation. When relative bulk density was plotted against UCS, a non-linear relationship was found characteristic of an isotropic open celled material. It was found by image analysis that the pore size distribution did not change and there was no degradation of the macrostructure when replicating the ceramic from the initial polyurethane template during processing. However, the pore size distributions did shift to a lower size by about 0.5 mm due to the firing process. The ceramic foams were found to exhibit mechanical properties typical of isotropic open cellular foams.

  4. Compressive properties of commercially available polyurethane foams as mechanical models for osteoporotic human cancellous bone

    PubMed Central

    Patel, Purvi SD; Shepherd, Duncan ET; Hukins, David WL

    2008-01-01

    Background Polyurethane (PU) foam is widely used as a model for cancellous bone. The higher density foams are used as standard biomechanical test materials, but none of the low density PU foams are universally accepted as models for osteoporotic (OP) bone. The aim of this study was to determine whether low density PU foam might be suitable for mimicking human OP cancellous bone. Methods Quasi-static compression tests were performed on PU foam cylinders of different lengths (3.9 and 7.7 mm) and of different densities (0.09, 0.16 and 0.32 g.cm-3), to determine the Young's modulus, yield strength and energy absorbed to yield. Results Young's modulus values were 0.08–0.93 MPa for the 0.09 g.cm-3 foam and from 15.1–151.4 MPa for the 0.16 and 0.32 g.cm-3 foam. Yield strength values were 0.01–0.07 MPa for the 0.09 g.cm-3 foam and from 0.9–4.5 MPa for the 0.16 and 0.32 g.cm-3 foam. The energy absorbed to yield was found to be negligible for all foam cylinders. Conclusion Based on these results, it is concluded that 0.16 g.cm-3 PU foam may prove to be suitable as an OP cancellous bone model when fracture stress, but not energy dissipation, is of concern. PMID:18844988

  5. Physical and chemical evaluation of furniture waste briquettes.

    PubMed

    Moreno, Ana Isabel; Font, Rafael; Conesa, Juan A

    2016-03-01

    Furniture waste is mainly composed of wood and upholstery foam (mostly polyurethane foam). Both of these have a high calorific value, therefore, energy recovery would be an appropriate process to manage these wastes. Nevertheless, the drawback is that the energy content of these wastes is limited due to their low density mainly that of upholstery foam. Densification of separate foam presents difficulties due to its elastic character. The significance of this work lies in obtaining densified material by co-densification of furniture wood waste and polyurethane foam waste. Densification of furniture wood and the co-densification of furniture wood waste with polyurethane foam have been studied. On the one hand, the parameters that have an effect on the quality of the furniture waste briquettes have been analysed, i.e., moisture content, compaction pressure, presence of lignin, etc. The maximum weight percentage of polyurethane foam that can be added with furniture wood waste to obtain durable briquettes and the optimal moisture were determined. On the other hand, some parameters were analysed in order to evaluate the possible effect on the combustion. The chemical composition of waste wood was compared with untreated wood biomass; the higher nitrogen content and the concentration of some metals were the most important differences, with a significant difference of Ti content. Copyright © 2016 Elsevier Ltd. All rights reserved.

  6. A finite element/level set model of polyurethane foam expansion and polymerization

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Rao, Rekha R.; Long, Kevin Nicholas; Roberts, Christine Cardinal

    Polyurethane foams are used widely for encapsulation and structural purposes because they are inexpensive, straightforward to process, amenable to a wide range of density variations (1 lb/ft3 - 50 lb/ft3), and able to fill complex molds quickly and effectively. Computational model of the filling and curing process are needed to reduce defects such as voids, out-of-specification density, density gradients, foam decomposition from high temperatures due to exotherms, and incomplete filling. This paper details the development of a computational fluid dynamics model of a moderate density PMDI structural foam, PMDI-10. PMDI is an isocyanate-based polyurethane foam, which is chemically blown withmore » water. The polyol reacts with isocyanate to produces the polymer. PMDI- 10 is catalyzed giving it a short pot life: it foams and polymerizes to a solid within 5 minutes during normal processing. To achieve a higher density, the foam is over-packed to twice or more of its free rise density of 10 lb/ft3. The goal for modeling is to represent the expansion, filling of molds, and the polymerization of the foam. This will be used to reduce defects, optimize the mold design, troubleshoot the processed, and predict the final foam properties. A homogenized continuum model foaming and curing was developed based on reaction kinetics, documented in a recent paper; it uses a simplified mathematical formalism that decouples these two reactions. The chemo-rheology of PMDI is measured experimentally and fit to a generalized- Newtonian viscosity model that is dependent on the extent of cure, gas fraction, and temperature. The conservation equations, including the equations of motion, an energy balance, and three rate equations are solved via a stabilized finite element method. The equations are combined with a level set method to determine the location of the foam-gas interface as it evolves to fill the mold. Understanding the thermal history and loads on the foam due to exothermicity and oven curing is very important to the results, since the kinetics, viscosity, and other material properties are all sensitive to temperature. Results from the model are compared to experimental flow visualization data and post-test X-ray computed tomography (CT) data for the density. Several geometries are investigated including two configurations of a mock structural part and a bar geometry to specifically test the density model. We have found that the model predicts both average density and filling profiles well. However, it under predicts density gradients, especially in the gravity direction. Further model improvements are also discussed for future work.« less

  7. Compressive and shear properties of commercially available polyurethane foams.

    PubMed

    Thompson, Mark S; McCarthy, Ian D; Lidgren, Lars; Ryd, Leif

    2003-10-01

    The shear properties of rigid polyurethane (PU-R) foams, routinely used to simulate cancellous bone, are not well characterized. The present assessment of the shear and compressive properties of four grades of Sawbones "Rigid cellular" PU-R foam tested 20 mm gauge diameter dumb-bell specimens in torsion and under axial loading. Shear moduli ranged from 13.3 to 99.7 MPa, shear strengths from 0.7 MPa to 4.2 MPa. Compressive yield strains varied little with density while shear yield strains had peak values with "200 kgm-3" grade. PU-R foams may be used to simulate the elastic but not failure properties of cancellous bone.

  8. Polyurethane Foams for Thermal Insulation Uses Produced from Castor Oil and Crude Glycerol Biopolyols.

    PubMed

    Carriço, Camila S; Fraga, Thaís; Carvalho, Vagner E; Pasa, Vânya M D

    2017-07-02

    Rigid polyurethane foams were synthesized using a renewable polyol from the simple physical mixture of castor oil and crude glycerol. The effect of the catalyst (DBTDL) content and blowing agents in the foams' properties were evaluated. The use of physical blowing agents (cyclopentane and n-pentane) allowed foams with smaller cells to be obtained in comparison with the foams produced with a chemical blowing agent (water). The increase of the water content caused a decrease in density, thermal conductivity, compressive strength, and Young's modulus, which indicates that the increment of CO₂ production contributes to the formation of larger cells. Higher amounts of catalyst in the foam formulations caused a slight density decrease and a small increase of thermal conductivity, compressive strength, and Young's modulus values. These green foams presented properties that indicate a great potential to be used as thermal insulation: density (23-41 kg·m -3 ), thermal conductivity (0.0128-0.0207 W·m -1 ·K -1 ), compressive strength (45-188 kPa), and Young's modulus (3-28 kPa). These biofoams are also environmentally friendly polymers and can aggregate revenue to the biodiesel industry, contributing to a reduction in fuel prices.

  9. A low-cost density reference phantom for computed tomography.

    PubMed

    Levine, Zachary H; Li, Mingdong; Reeves, Anthony P; Yankelevitz, David F; Chen, Joseph J; Siegel, Eliot L; Peskin, Adele; Zeiger, Diana N

    2009-02-01

    The authors characterized a commercially available foam composed of polyurethane and polyisocyanurate which is marketed for modeling parts in the aircraft, automotive, and related industries. The authors found that the foam may be suitable for use as a density reference standard in the range below -400 Hounsfield units. This range is coincident with the density of lung tissue. The foam may be helpful in making the diagnosis of lung disease more systematic.

  10. Quantum Chemical Simulation of the Interaction of Functional Groups in Polyurethanes with 3 d-Metal Ions During Their Extraction from Aqueous Solutions

    NASA Astrophysics Data System (ADS)

    Ksenofontov, M. A.; Bobkova, E. Yu.; Shundalau, M. B.; Ostrovskaya, L. E.; Vasil'eva, V. S.

    2017-11-01

    The interaction of the functional groups in the polyurethane foam adsorbent Penopurm® with the cations of some 3d-metals upon their extraction from aqueous solutions has been studied by atomic emission spectroscopy, UV/Vis and vibrational IR spectroscopy, and quantum chemical simulation using density functional theory. Penopurm® absorbs 3d-metal cations from aqueous solutions in the pH range 5-7. Some spectral criteria have been found indicating a predominant interaction of Ni2+ ions with various fragments of the polyurethane foam structure.

  11. Modeling shock-driven reaction in low density PMDI foam

    NASA Astrophysics Data System (ADS)

    Brundage, Aaron; Alexander, C. Scott; Reinhart, William; Peterson, David

    Shock experiments on low density polyurethane foams reveal evidence of reaction at low impact pressures. However, these reaction thresholds are not evident over the low pressures reported for historical Hugoniot data of highly distended polyurethane at densities below 0.1 g/cc. To fill this gap, impact data given in a companion paper for polymethylene diisocyanate (PMDI) foam with a density of 0.087 g/cc were acquired for model validation. An equation of state (EOS) was developed to predict the shock response of these highly distended materials over the full range of impact conditions representing compaction of the inert material, low-pressure decomposition, and compression of the reaction products. A tabular SESAME EOS of the reaction products was generated using the JCZS database in the TIGER equilibrium code. In particular, the Arrhenius Burn EOS, a two-state model which transitions from an unreacted to a reacted state using single step Arrhenius kinetics, as implemented in the shock physics code CTH, was modified to include a statistical distribution of states. Hence, a single EOS is presented that predicts the onset to reaction due to shock loading in PMDI-based polyurethane foams. Sandia National Laboratories is a multi-program laboratory managed and operated by Sandia Corporation, a wholly owned subsidiary of Lockheed Martin Corporation, for the U.S. Department of Energy's NNSA under Contract DE-AC04-94AL85000.

  12. A low-cost density reference phantom for computed tomography

    PubMed Central

    Levine, Zachary H.; Li, Mingdong; Reeves, Anthony P.; Yankelevitz, David F.; Chen, Joseph J.; Siegel, Eliot L.; Peskin, Adele; Zeiger, Diana N.

    2009-01-01

    The authors characterized a commercially available foam composed of polyurethane and polyisocyanurate which is marketed for modeling parts in the aircraft, automotive, and related industries. The authors found that the foam may be suitable for use as a density reference standard in the range below −400 Hounsfield units. This range is coincident with the density of lung tissue. The foam may be helpful in making the diagnosis of lung disease more systematic. PMID:19291968

  13. Morphological and performance measures of polyurethane foams using X-ray CT and mechanical testing.

    PubMed

    Patterson, Brian M; Henderson, Kevin; Gilbertson, Robert D; Tornga, Stephanie; Cordes, Nikolaus L; Chavez, Manuel E; Smith, Zachary

    2014-08-01

    Meso-scale structure in polymeric foams determines the mechanical properties of the material. Density variations, even more than variations in the anisotropic void structure, can greatly vary the compressive and tensile response of the material. With their diverse use as both a structural material and space filler, polyurethane (PU) foams are widely studied. In this manuscript, quantitative measures of the density and anisotropic structure are provided by using micro X-ray computed tomography (microCT) to better understand the results of mechanical testing. MicroCT illustrates the variation in the density, cell morphology, size, shape, and orientation in different regions in blown foam due to the velocity profile near the casting surface. "Interrupted" in situ imaging of the material during compression of these sub-regions indicates the pathways of the structural response to the mechanical load and the changes in cell morphology as a result. It is found that molded PU foam has a 6 mm thick "skin" of higher density and highly eccentric morphological structure that leads to wide variations in mechanical performance depending upon sampling location. This comparison is necessary to understand the mechanical performance of the anisotropic structure.

  14. 40 CFR 63.1300 - Standards for molded flexible polyurethane foam production.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... polyurethane foam production. 63.1300 Section 63.1300 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY... Foam Production § 63.1300 Standards for molded flexible polyurethane foam production. Each owner or... polyurethane foam process, with the following exception. Diisocyanates may be used to flush the mixhead and...

  15. 40 CFR 63.1300 - Standards for molded flexible polyurethane foam production.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... polyurethane foam production. 63.1300 Section 63.1300 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY... Foam Production § 63.1300 Standards for molded flexible polyurethane foam production. Each owner or... polyurethane foam process, with the following exception. Diisocyanates may be used to flush the mixhead and...

  16. Tailoring properties of reticulated vitreous carbon foams with tunable density

    NASA Astrophysics Data System (ADS)

    Smorygo, Oleg; Marukovich, Alexander; Mikutski, Vitali; Stathopoulos, Vassilis; Hryhoryeu, Siarhei; Sadykov, Vladislav

    2016-06-01

    Reticulated vitreous carbon (RVC) foams were manufactured by multiple replications of a polyurethane foam template structure using ethanolic solutions of phenolic resin. The aims were to create an algorithm of fine tuning the precursor foam density and ensure an open-cell reticulated porous structure in a wide density range. The precursor foams were pyrolyzed in inert atmospheres at 700°C, 1100°C and 2000°C, and RVC foams with fully open cells and tunable bulk densities within 0.09-0.42 g/cm3 were synthesized. The foams were characterized in terms of porous structure, carbon lattice parameters, mechanical properties, thermal conductivity, electric conductivity, and corrosive resistance. The reported manufacturing approach is suitable for designing the foam microstructure, including the strut design with a graded microstructure.

  17. Ultra Low Density and Highly Crosslinked Biocompatible Shape Memory Polyurethane Foams

    PubMed Central

    Singhal, Pooja; Rodriguez, Jennifer N.; Small, Ward; Eagleston, Scott; Van de Water, Judy; Maitland, Duncan J.; Wilson, Thomas S.

    2012-01-01

    We report the development of highly chemically crosslinked, ultra low density (~0.015 g/cc) polyurethane shape memory foams synthesized from symmetrical, low molecular weight and branched hydroxyl monomers. Sharp single glass transitions (Tg) customizable in the functional range of 45–70 °C were achieved. Thermomechanical testing confirmed shape memory behavior with 97–98% shape recovery over repeated cycles, a glassy storage modulus of 200–300 kPa and recovery stresses of 5–15 kPa. Shape holding tests under constrained storage above the Tg showed stable shape memory. A high volume expansion of up to 70 times was seen on actuation of these foams from a fully compressed state. Low in-vitro cell activation induced by the foam compared to controls demonstrates low acute bio-reactivity. We believe these porous polymeric scaffolds constitute an important class of novel smart biomaterials with multiple potential applications. PMID:22570509

  18. 40 CFR 63.1299 - Standards for slabstock flexible polyurethane foam production-source-wide emission limitation.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... polyurethane foam production-source-wide emission limitation. 63.1299 Section 63.1299 Protection of Environment... Flexible Polyurethane Foam Production § 63.1299 Standards for slabstock flexible polyurethane foam... procedures in paragraphs (c)(1) through (4) of this section, unless a recovery device is used. Slabstock foam...

  19. 40 CFR 63.1299 - Standards for slabstock flexible polyurethane foam production-source-wide emission limitation.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... polyurethane foam production-source-wide emission limitation. 63.1299 Section 63.1299 Protection of Environment... Flexible Polyurethane Foam Production § 63.1299 Standards for slabstock flexible polyurethane foam... procedures in paragraphs (c)(1) through (4) of this section, unless a recovery device is used. Slabstock foam...

  20. 40 CFR 63.1299 - Standards for slabstock flexible polyurethane foam production-source-wide emission limitation.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... polyurethane foam production-source-wide emission limitation. 63.1299 Section 63.1299 Protection of Environment... Flexible Polyurethane Foam Production § 63.1299 Standards for slabstock flexible polyurethane foam... procedures in paragraphs (c)(1) through (4) of this section, unless a recovery device is used. Slabstock foam...

  1. 40 CFR 63.1297 - Standards for slabstock flexible polyurethane foam production-HAP ABA emissions from the...

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... polyurethane foam production-HAP ABA emissions from the production line. 63.1297 Section 63.1297 Protection of... Pollutants for Flexible Polyurethane Foam Production § 63.1297 Standards for slabstock flexible polyurethane... § 63.1293(a)(1) shall control HAP ABA emissions from the slabstock polyurethane foam production line in...

  2. 40 CFR 63.1297 - Standards for slabstock flexible polyurethane foam production-HAP ABA emissions from the...

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... polyurethane foam production-HAP ABA emissions from the production line. 63.1297 Section 63.1297 Protection of... Pollutants for Flexible Polyurethane Foam Production § 63.1297 Standards for slabstock flexible polyurethane... § 63.1293(a)(1) shall control HAP ABA emissions from the slabstock polyurethane foam production line in...

  3. 40 CFR 63.1297 - Standards for slabstock flexible polyurethane foam production-HAP ABA emissions from the...

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... polyurethane foam production-HAP ABA emissions from the production line. 63.1297 Section 63.1297 Protection of... Pollutants for Flexible Polyurethane Foam Production § 63.1297 Standards for slabstock flexible polyurethane... § 63.1293(a)(1) shall control HAP ABA emissions from the slabstock polyurethane foam production line in...

  4. 40 CFR 63.1293 - Standards for slabstock flexible polyurethane foam production.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... polyurethane foam production. 63.1293 Section 63.1293 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY... CATEGORIES (CONTINUED) National Emission Standards for Hazardous Air Pollutants for Flexible Polyurethane Foam Production § 63.1293 Standards for slabstock flexible polyurethane foam production. Each owner or...

  5. 40 CFR 63.1293 - Standards for slabstock flexible polyurethane foam production.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... polyurethane foam production. 63.1293 Section 63.1293 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY... CATEGORIES (CONTINUED) National Emission Standards for Hazardous Air Pollutants for Flexible Polyurethane Foam Production § 63.1293 Standards for slabstock flexible polyurethane foam production. Each owner or...

  6. 40 CFR 63.1294 - Standards for slabstock flexible polyurethane foam production-diisocyanate emissions.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... polyurethane foam production-diisocyanate emissions. 63.1294 Section 63.1294 Protection of Environment... Pollutants for Flexible Polyurethane Foam Production § 63.1294 Standards for slabstock flexible polyurethane foam production—diisocyanate emissions. Each new and existing slabstock affected source shall comply...

  7. 40 CFR 63.1294 - Standards for slabstock flexible polyurethane foam production-diisocyanate emissions.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... polyurethane foam production-diisocyanate emissions. 63.1294 Section 63.1294 Protection of Environment... Pollutants for Flexible Polyurethane Foam Production § 63.1294 Standards for slabstock flexible polyurethane foam production—diisocyanate emissions. Each new and existing slabstock affected source shall comply...

  8. Lung pair phantom

    DOEpatents

    Olsen, Peter C.; Gordon, N. Ross; Simmons, Kevin L.

    1993-01-01

    The present invention is a material and method of making the material that exhibits improved radiation attenuation simulation of real lungs, i.e., an "authentic lung tissue" or ALT phantom. Specifically, the ALT phantom is a two-part polyurethane medium density foam mixed with calcium carbonate, potassium carbonate if needed for K-40 background, lanthanum nitrate, acetone, and a nitrate or chloride form of a radionuclide. This formulation is found to closely match chemical composition and linear attenuation of real lungs. The ALT phantom material is made according to established procedures but without adding foaming agents or preparing thixotropic concentrate and with a modification for ensuring uniformity of density of the ALT phantom that is necessary for accurate simulation. The modification is that the polyurethane chemicals are mixed at a low temperature prior to pouring the polyurethane mixture into the mold.

  9. Lung pair phantom

    DOEpatents

    Olsen, P.C.; Gordon, N.R.; Simmons, K.L.

    1993-11-30

    The present invention is a material and method of making the material that exhibits improved radiation attenuation simulation of real lungs, i.e., an ``authentic lung tissue`` or ALT phantom. Specifically, the ALT phantom is a two-part polyurethane medium density foam mixed with calcium carbonate, potassium carbonate if needed for K-40 background, lanthanum nitrate, acetone, and a nitrate or chloride form of a radionuclide. This formulation is found to closely match chemical composition and linear attenuation of real lungs. The ALT phantom material is made according to established procedures but without adding foaming agents or preparing thixotropic concentrate and with a modification for ensuring uniformity of density of the ALT phantom that is necessary for accurate simulation. The modification is that the polyurethane chemicals are mixed at a low temperature prior to pouring the polyurethane mixture into the mold.

  10. 40 CFR 63.1294 - Standards for slabstock flexible polyurethane foam production-diisocyanate emissions.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... 40 Protection of Environment 11 2010-07-01 2010-07-01 true Standards for slabstock flexible polyurethane foam production-diisocyanate emissions. 63.1294 Section 63.1294 Protection of Environment... Flexible Polyurethane Foam Production § 63.1294 Standards for slabstock flexible polyurethane foam...

  11. 40 CFR 63.1300 - Standards for molded flexible polyurethane foam production.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... polyurethane foam production. 63.1300 Section 63.1300 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY... CATEGORIES National Emission Standards for Hazardous Air Pollutants for Flexible Polyurethane Foam Production § 63.1300 Standards for molded flexible polyurethane foam production. Each owner or operator of a new...

  12. 40 CFR 63.1294 - Standards for slabstock flexible polyurethane foam production-diisocyanate emissions.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... 40 Protection of Environment 12 2012-07-01 2011-07-01 true Standards for slabstock flexible polyurethane foam production-diisocyanate emissions. 63.1294 Section 63.1294 Protection of Environment... Flexible Polyurethane Foam Production § 63.1294 Standards for slabstock flexible polyurethane foam...

  13. 40 CFR 63.1300 - Standards for molded flexible polyurethane foam production.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... polyurethane foam production. 63.1300 Section 63.1300 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY... CATEGORIES National Emission Standards for Hazardous Air Pollutants for Flexible Polyurethane Foam Production § 63.1300 Standards for molded flexible polyurethane foam production. Each owner or operator of a new...

  14. 40 CFR 63.1293 - Standards for slabstock flexible polyurethane foam production.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... polyurethane foam production. 63.1293 Section 63.1293 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY... CATEGORIES National Emission Standards for Hazardous Air Pollutants for Flexible Polyurethane Foam Production § 63.1293 Standards for slabstock flexible polyurethane foam production. Each owner or operator of a...

  15. 40 CFR 63.1294 - Standards for slabstock flexible polyurethane foam production-diisocyanate emissions.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... 40 Protection of Environment 11 2011-07-01 2011-07-01 false Standards for slabstock flexible polyurethane foam production-diisocyanate emissions. 63.1294 Section 63.1294 Protection of Environment... Flexible Polyurethane Foam Production § 63.1294 Standards for slabstock flexible polyurethane foam...

  16. 40 CFR 63.1293 - Standards for slabstock flexible polyurethane foam production.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... polyurethane foam production. 63.1293 Section 63.1293 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY... CATEGORIES National Emission Standards for Hazardous Air Pollutants for Flexible Polyurethane Foam Production § 63.1293 Standards for slabstock flexible polyurethane foam production. Each owner or operator of a...

  17. 40 CFR 63.1300 - Standards for molded flexible polyurethane foam production.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... polyurethane foam production. 63.1300 Section 63.1300 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY... CATEGORIES National Emission Standards for Hazardous Air Pollutants for Flexible Polyurethane Foam Production § 63.1300 Standards for molded flexible polyurethane foam production. Each owner or operator of a new...

  18. 40 CFR 63.1293 - Standards for slabstock flexible polyurethane foam production.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... polyurethane foam production. 63.1293 Section 63.1293 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY... CATEGORIES National Emission Standards for Hazardous Air Pollutants for Flexible Polyurethane Foam Production § 63.1293 Standards for slabstock flexible polyurethane foam production. Each owner or operator of a...

  19. 40 CFR 63.1296 - Standards for slabstock flexible polyurethane foam production-HAP ABA equipment leaks.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... polyurethane foam production-HAP ABA equipment leaks. 63.1296 Section 63.1296 Protection of Environment... Flexible Polyurethane Foam Production § 63.1296 Standards for slabstock flexible polyurethane foam... emissions from leaks from transfer pumps, valves, connectors, pressure-relief valves, and open-ended lines...

  20. 40 CFR 63.1296 - Standards for slabstock flexible polyurethane foam production-HAP ABA equipment leaks.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... polyurethane foam production-HAP ABA equipment leaks. 63.1296 Section 63.1296 Protection of Environment... Flexible Polyurethane Foam Production § 63.1296 Standards for slabstock flexible polyurethane foam... emissions from leaks from transfer pumps, valves, connectors, pressure-relief valves, and open-ended lines...

  1. 40 CFR 63.1296 - Standards for slabstock flexible polyurethane foam production-HAP ABA equipment leaks.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... polyurethane foam production-HAP ABA equipment leaks. 63.1296 Section 63.1296 Protection of Environment... Flexible Polyurethane Foam Production § 63.1296 Standards for slabstock flexible polyurethane foam... emissions from leaks from transfer pumps, valves, connectors, pressure-relief valves, and open-ended lines...

  2. 40 CFR 63.1295 - Standards for slabstock flexible polyurethane foam production-HAP ABA storage vessels.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... 40 Protection of Environment 11 2010-07-01 2010-07-01 true Standards for slabstock flexible polyurethane foam production-HAP ABA storage vessels. 63.1295 Section 63.1295 Protection of Environment... Flexible Polyurethane Foam Production § 63.1295 Standards for slabstock flexible polyurethane foam...

  3. 40 CFR 63.1295 - Standards for slabstock flexible polyurethane foam production-HAP ABA storage vessels.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... 40 Protection of Environment 11 2011-07-01 2011-07-01 false Standards for slabstock flexible polyurethane foam production-HAP ABA storage vessels. 63.1295 Section 63.1295 Protection of Environment... Flexible Polyurethane Foam Production § 63.1295 Standards for slabstock flexible polyurethane foam...

  4. 40 CFR 63.1295 - Standards for slabstock flexible polyurethane foam production-HAP ABA storage vessels.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... 40 Protection of Environment 12 2012-07-01 2011-07-01 true Standards for slabstock flexible polyurethane foam production-HAP ABA storage vessels. 63.1295 Section 63.1295 Protection of Environment... Flexible Polyurethane Foam Production § 63.1295 Standards for slabstock flexible polyurethane foam...

  5. 40 CFR 63.1292 - Definitions.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... water. Flexible polyurethane foams are open-celled, permit the passage of air through the foam, and... Standards for Hazardous Air Pollutants for Flexible Polyurethane Foam Production § 63.1292 Definitions. All... for the purposes of this subpart. Cured foam means flexible polyurethane foam with fully developed...

  6. 40 CFR 63.1292 - Definitions.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... water. Flexible polyurethane foams are open-celled, permit the passage of air through the foam, and... Hazardous Air Pollutants for Flexible Polyurethane Foam Production § 63.1292 Definitions. All terms used in... purposes of this subpart. Cured foam means flexible polyurethane foam with fully developed physical...

  7. 40 CFR 63.1292 - Definitions.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... water. Flexible polyurethane foams are open-celled, permit the passage of air through the foam, and... Standards for Hazardous Air Pollutants for Flexible Polyurethane Foam Production § 63.1292 Definitions. All... for the purposes of this subpart. Cured foam means flexible polyurethane foam with fully developed...

  8. 40 CFR 63.1292 - Definitions.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... water. Flexible polyurethane foams are open-celled, permit the passage of air through the foam, and... Hazardous Air Pollutants for Flexible Polyurethane Foam Production § 63.1292 Definitions. All terms used in... purposes of this subpart. Cured foam means flexible polyurethane foam with fully developed physical...

  9. 40 CFR 63.1296 - Standards for slabstock flexible polyurethane foam production-HAP ABA equipment leaks.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... polyurethane foam production-HAP ABA equipment leaks. 63.1296 Section 63.1296 Protection of Environment... Pollutants for Flexible Polyurethane Foam Production § 63.1296 Standards for slabstock flexible polyurethane foam production—HAP ABA equipment leaks. Each owner or operator of a new or existing slabstock affected...

  10. 40 CFR 63.1296 - Standards for slabstock flexible polyurethane foam production-HAP ABA equipment leaks.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... polyurethane foam production-HAP ABA equipment leaks. 63.1296 Section 63.1296 Protection of Environment... Pollutants for Flexible Polyurethane Foam Production § 63.1296 Standards for slabstock flexible polyurethane foam production—HAP ABA equipment leaks. Each owner or operator of a new or existing slabstock affected...

  11. 40 CFR 63.1298 - Standards for slabstock flexible polyurethane foam production-HAP emissions from equipment cleaning.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... polyurethane foam production-HAP emissions from equipment cleaning. 63.1298 Section 63.1298 Protection of... Hazardous Air Pollutants for Flexible Polyurethane Foam Production § 63.1298 Standards for slabstock flexible polyurethane foam production—HAP emissions from equipment cleaning. Each owner or operator of a...

  12. 40 CFR 63.1298 - Standards for slabstock flexible polyurethane foam production-HAP emissions from equipment cleaning.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... polyurethane foam production-HAP emissions from equipment cleaning. 63.1298 Section 63.1298 Protection of... Pollutants for Flexible Polyurethane Foam Production § 63.1298 Standards for slabstock flexible polyurethane foam production—HAP emissions from equipment cleaning. Each owner or operator of a new or existing...

  13. 40 CFR 63.1298 - Standards for slabstock flexible polyurethane foam production-HAP emissions from equipment cleaning.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... polyurethane foam production-HAP emissions from equipment cleaning. 63.1298 Section 63.1298 Protection of... Hazardous Air Pollutants for Flexible Polyurethane Foam Production § 63.1298 Standards for slabstock flexible polyurethane foam production—HAP emissions from equipment cleaning. Each owner or operator of a...

  14. 40 CFR 63.1295 - Standards for slabstock flexible polyurethane foam production-HAP ABA storage vessels.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... polyurethane foam production-HAP ABA storage vessels. 63.1295 Section 63.1295 Protection of Environment... Pollutants for Flexible Polyurethane Foam Production § 63.1295 Standards for slabstock flexible polyurethane foam production—HAP ABA storage vessels. Each owner or operator of a new or existing slabstock affected...

  15. 40 CFR 63.1297 - Standards for slabstock flexible polyurethane foam production-HAP ABA emissions from the...

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... polyurethane foam production-HAP ABA emissions from the production line. 63.1297 Section 63.1297 Protection of... Hazardous Air Pollutants for Flexible Polyurethane Foam Production § 63.1297 Standards for slabstock flexible polyurethane foam production—HAP ABA emissions from the production line. (a) Each owner or...

  16. 40 CFR 63.1295 - Standards for slabstock flexible polyurethane foam production-HAP ABA storage vessels.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... polyurethane foam production-HAP ABA storage vessels. 63.1295 Section 63.1295 Protection of Environment... Pollutants for Flexible Polyurethane Foam Production § 63.1295 Standards for slabstock flexible polyurethane foam production—HAP ABA storage vessels. Each owner or operator of a new or existing slabstock affected...

  17. 40 CFR 63.1298 - Standards for slabstock flexible polyurethane foam production-HAP emissions from equipment cleaning.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... polyurethane foam production-HAP emissions from equipment cleaning. 63.1298 Section 63.1298 Protection of... Pollutants for Flexible Polyurethane Foam Production § 63.1298 Standards for slabstock flexible polyurethane foam production—HAP emissions from equipment cleaning. Each owner or operator of a new or existing...

  18. 40 CFR 63.1299 - Standards for slabstock flexible polyurethane foam production-source-wide emission limitation.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... polyurethane foam production-source-wide emission limitation. 63.1299 Section 63.1299 Protection of Environment... Pollutants for Flexible Polyurethane Foam Production § 63.1299 Standards for slabstock flexible polyurethane foam production—source-wide emission limitation. Each owner or operator of a new or existing slabstock...

  19. 40 CFR 63.1297 - Standards for slabstock flexible polyurethane foam production-HAP ABA emissions from the...

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... polyurethane foam production-HAP ABA emissions from the production line. 63.1297 Section 63.1297 Protection of... Hazardous Air Pollutants for Flexible Polyurethane Foam Production § 63.1297 Standards for slabstock flexible polyurethane foam production—HAP ABA emissions from the production line. (a) Each owner or...

  20. 40 CFR 63.1299 - Standards for slabstock flexible polyurethane foam production-source-wide emission limitation.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... polyurethane foam production-source-wide emission limitation. 63.1299 Section 63.1299 Protection of Environment... Pollutants for Flexible Polyurethane Foam Production § 63.1299 Standards for slabstock flexible polyurethane foam production—source-wide emission limitation. Each owner or operator of a new or existing slabstock...

  1. 40 CFR 63.1298 - Standards for slabstock flexible polyurethane foam production-HAP emissions from equipment cleaning.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... polyurethane foam production-HAP emissions from equipment cleaning. 63.1298 Section 63.1298 Protection of... Pollutants for Flexible Polyurethane Foam Production § 63.1298 Standards for slabstock flexible polyurethane foam production—HAP emissions from equipment cleaning. Each owner or operator of a new or existing...

  2. Study of nonuniformity of mechanical properties of rigid polyurethane foam in blocks obtained by free foaming. 1. Blocks with cylindrical form

    NASA Astrophysics Data System (ADS)

    Zhmud, N. P.; Solodovnik, P. I.; Yakushin, V. Ya.

    1983-05-01

    In PUF blocks with vertical walls and circular cross section (H/D=0.4-8) obtained by free foaming, a regular change in the mechanical properties in the bulk of the material is observed, which is not related to a change in density,

  3. The performance of lightweight plastic foams developed for fire safety

    NASA Technical Reports Server (NTRS)

    Fish, R. H.

    1971-01-01

    The use of a low density, polyurethane based foam to suppress a fire and to provide protection for the structure of an aircraft or spacecraft is discussed. The mechanism by which foams provide protection from heat and create a nonflammable surface is described. Various materials and their application to specific types of structures are examined.

  4. Green waste cooking oil-based rigid polyurethane foam

    NASA Astrophysics Data System (ADS)

    Enderus, N. F.; Tahir, S. M.

    2017-11-01

    Polyurethane is a versatile polymer traditionally prepared using petroleum-based raw material. Petroleum, however, is a non-renewable material and polyurethane produced was found to be non-biodegradable. In quest for a more environmentally friendly alternative, wastecooking oil, a highly abundant domestic waste with easily derivatized structure, is a viable candidate to replace petroleum. In this study,an investigation to determine physical and chemical properties of rigid polyurethane (PU) foam from waste cooking oil (WCO) was carried out. WCO was first adsorbed by using coconut husk activated carbon adsorbent prior to be used for polyol synthesis. The purified WCO was then used to synthesize polyol via transesterification reaction to yield alcohol groups in the WCO chains structure. Finally, the WCO-based polyol was used to prepare rigid PU foam. The optimum formulation for PU formation was found to be 90 polyol: 60 glycerol: 54 water: 40 diethanolamine: 23 diisocyanate. The rigid PU foam has density of 208.4 kg/m3 with maximum compressive strength and capability to receive load at 0.03 MPa and 0.09 kN, respectively. WCO-based PU can potentially be used to replace petroleum-based PU as house construction materials such as insulation panels.

  5. Histopathological reaction over prosthesis surface covered with silicone and polyurethane foam implanted in rats.

    PubMed

    Wagenführ-Júnior, Jorge; Ribas Filho, Jurandir Marcondes; Nascimento, Marcelo Mazza do; Ribas, Fernanda Marcondes; Wanka, Marcus Vinícius; Godoi, Andressa de Lima

    2012-12-01

    To evaluate whether polyurethane foam leads more intense foreign-body reaction than silicone foam. To compare the vascularization of the capsules surrounding the foam implants. To investigate if the capsule of polyurethane foam implanted has greater amount of collagen than that of silicone foam. Sixty-four young male Wistar rats were allocated into two groups: polyurethane foam and silicone foam. Subcutaneous discs were implanted into the dorsum of the animals in both groups. The capsules were assessed 28 days, two months, three months and six months postoperatively. Microscopic analysis with H&E stain was performed to evaluate the acute and chronic inflammatory process, foreign-body reaction and neovascularization. The analysis with picrosirius red was performed using the ImageProPlus software, to measure the number of vessels and collagen types I and III. There were no statistical differences between the two groups regarding the acute and chronic inflammatory processes. All rats from the polyurethane group, in all times, exhibited moderate or intense foreign-body reaction, with statistic significant difference (p=0.046) when compared with the silicone group, in which the reaction was either mild or nonexistent at two months. Vascular proliferation was significantly different between the groups at 28 days (p=0.0002), with the polyurethane group displaying greater neovascularization with H&E stain. Similar results were obtained with picrosirius red, which revealed in the polyurethane group a much greater number of vessels than in the silicone group (p=0.001). The collagen area was larger in the polyurethane group, significantly at 28 days (p=0.001) and at two months (p=0.030). Polyurethane foam elicited more intense foreign-body reaction when compared with silicone foam. The number of vessels was higher in the capsules of the polyurethane foam implants 28 days after the operation. The capsule of the polyurethane foam implants showed a greater amount of collagen than that of the silicone foam implants.

  6. Material Characterization and Computer Model Simulation of Low Density Polyurethane Foam Used in a Rodent Traumatic Brain Injury Model

    PubMed Central

    Zhang, Liying; Gurao, Manish; Yang, King H.; King, Albert I.

    2011-01-01

    Computer models of the head can be used to simulate the events associated with traumatic brain injury (TBI) and quantify biomechanical response within the brain. Marmarou’s impact acceleration rodent model is a widely used experimental model of TBI mirroring axonal pathology in humans. The mechanical properties of the low density polyurethane (PU) foam, an essential piece of energy management used in Marmarou’s impact device, has not been fully characterized. The foam used in Marmarou’s device was tested at seven strain rates ranging from quasi-static to dynamic (0.014 ~ 42.86 s−1) to quantify the stress-strain relationships in compression. Recovery rate of the foam after cyclic compression was also determined through the periods of recovery up to three weeks. The experimentally determined stress-strain curves were incorporated into a material model in an explicit Finite Element (FE) solver to validate the strain rate dependency of the FE foam model. Compression test results have shown that the foam used in the rodent impact acceleration model is strain rate dependent. The foam has been found to be reusable for multiple impacts. However the stress resistance of used foam is reduced to 70% of the new foam. The FU_CHANG_FOAM material model in an FE solver has been found to be adequate to simulate this rate sensitive foam. PMID:21459114

  7. Material characterization and computer model simulation of low density polyurethane foam used in a rodent traumatic brain injury model.

    PubMed

    Zhang, Liying; Gurao, Manish; Yang, King H; King, Albert I

    2011-05-15

    Computer models of the head can be used to simulate the events associated with traumatic brain injury (TBI) and quantify biomechanical response within the brain. Marmarou's impact acceleration rodent model is a widely used experimental model of TBI mirroring axonal pathology in humans. The mechanical properties of the low density polyurethane (PU) foam, an essential piece of energy management used in Marmarou's impact device, has not been fully characterized. The foam used in Marmarou's device was tested at seven strain rates ranging from quasi-static to dynamic (0.014-42.86 s⁻¹) to quantify the stress-strain relationships in compression. Recovery rate of the foam after cyclic compression was also determined through the periods of recovery up to three weeks. The experimentally determined stress-strain curves were incorporated into a material model in an explicit Finite Element (FE) solver to validate the strain rate dependency of the FE foam model. Compression test results have shown that the foam used in the rodent impact acceleration model is strain rate dependent. The foam has been found to be reusable for multiple impacts. However the stress resistance of used foam is reduced to 70% of the new foam. The FU_CHANG_FOAM material model in an FE solver has been found to be adequate to simulate this rate sensitive foam. Copyright © 2011 Elsevier B.V. All rights reserved.

  8. Electrically conductive rigid polyurethane foam

    DOEpatents

    Neet, T.E.; Spieker, D.A.

    1983-12-08

    A rigid, moldable polyurethane foam comprises about 2 to 10 weight percent, based on the total foam weight, of a carbon black which is CONDUCTEX CC-40-220 or CONDUCTEX SC, whereby the rigid polyurethane foam is electrically conductive and has essentially the same mechanical properties as the same foam without carbon black added.

  9. Electrically conductive rigid polyurethane foam

    DOEpatents

    Neet, Thomas E.; Spieker, David A.

    1985-03-19

    A rigid, polyurethane foam comprises about 2-10 weight percent, based on the total foam weight, of a carbon black which is CONDUCTEX CC-40-220 or CONDUCTEX SC, whereby the rigid polyurethane foam is electrically conductive and has essentially the same mechanical properties as the same foam without carbon black added.

  10. 40 CFR 63.8784 - What parts of my plant does this subpart cover?

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... CATEGORIES (CONTINUED) National Emission Standards for Hazardous Air Pollutants: Flexible Polyurethane Foam... flexible polyurethane foam fabrication. (b) The affected sources are defined in this section in paragraphs... to bond foam to foam at a flexible polyurethane foam fabrication plant site. (2) The flame lamination...

  11. 40 CFR 63.8784 - What parts of my plant does this subpart cover?

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... CATEGORIES (CONTINUED) National Emission Standards for Hazardous Air Pollutants: Flexible Polyurethane Foam... flexible polyurethane foam fabrication. (b) The affected sources are defined in this section in paragraphs... to bond foam to foam at a flexible polyurethane foam fabrication plant site. (2) The flame lamination...

  12. 40 CFR 63.8784 - What parts of my plant does this subpart cover?

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... CATEGORIES (CONTINUED) National Emission Standards for Hazardous Air Pollutants: Flexible Polyurethane Foam... flexible polyurethane foam fabrication. (b) The affected sources are defined in this section in paragraphs... to bond foam to foam at a flexible polyurethane foam fabrication plant site. (2) The flame lamination...

  13. 40 CFR 63.8784 - What parts of my plant does this subpart cover?

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... CATEGORIES (CONTINUED) National Emission Standards for Hazardous Air Pollutants: Flexible Polyurethane Foam... flexible polyurethane foam fabrication. (b) The affected sources are defined in this section in paragraphs... to bond foam to foam at a flexible polyurethane foam fabrication plant site. (2) The flame lamination...

  14. 40 CFR 63.8784 - What parts of my plant does this subpart cover?

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... CATEGORIES (CONTINUED) National Emission Standards for Hazardous Air Pollutants: Flexible Polyurethane Foam... flexible polyurethane foam fabrication. (b) The affected sources are defined in this section in paragraphs... to bond foam to foam at a flexible polyurethane foam fabrication plant site. (2) The flame lamination...

  15. 46 CFR 160.035-1 - Applicable specifications.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... Laminates, Fibrous Glass Reinforced, Marine Structural. MIL-P-19644—Plastic Foam, Molded Polystyrene..., Polyester, Low Pressure Laminating, Fire Retardant. MIL-P-21929—Plastic Material, Cellular Polyurethane, Rigid, Foam-In-Place, Low Density. (3) Federal specifications: TT-P-59—Paint, Ready-Mixed, International...

  16. 46 CFR 160.035-1 - Applicable specifications.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... Laminates, Fibrous Glass Reinforced, Marine Structural. MIL-P-19644—Plastic Foam, Molded Polystyrene..., Polyester, Low Pressure Laminating, Fire Retardant. MIL-P-21929—Plastic Material, Cellular Polyurethane, Rigid, Foam-In-Place, Low Density. (3) Federal specifications: TT-P-59—Paint, Ready-Mixed, International...

  17. Effectiveness of Flame Retardants in TufFoam.

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Abelow, Alexis Elizabeth; Nissen, April; Massey, Lee Taylor

    An investigation of polyurethane foam filled with known flame retardant fillers including hydroxides, melamine, phosphate-containing compounds, and melamine phosphates was carried out to produce a low-cost material with high flame retardant efficiency. The impact of flame retardant fillers on the physical properties such a s composite foam density, glass transition temperature, storage modulus, and thermal expansion of composite foams was investigated with the goal of synthesizing a robust rigid foam with excellent flame retardant properties.

  18. Investigation of Shock Wave Attenuation in Porous Materials

    DTIC Science & Technology

    2009-12-01

    Foam ...... 38 Table 4. Summary of Material Characteristics of Polyurethane Foams ............ 40 Table 5. Summary of Experiment Results...polyurethane foam , he performed a simple symmetric impact simulation to investigate the material properties and wave propagation characteristics of the...describes the characteristics of the two foam materials studied in this research, namely the aluminum metal foam and rigid polyurethane foam , which

  19. 40 CFR 63.8782 - Am I subject to this subpart?

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ...) National Emission Standards for Hazardous Air Pollutants: Flexible Polyurethane Foam Fabrication Operations... you own or operate a flexible polyurethane foam fabrication plant site that operates a flame... flexible polyurethane foam fabrication plant site is a plant site where pieces of flexible polyurethane...

  20. 40 CFR 63.8782 - Am I subject to this subpart?

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ...) National Emission Standards for Hazardous Air Pollutants: Flexible Polyurethane Foam Fabrication Operations... you own or operate a flexible polyurethane foam fabrication plant site that operates a flame... flexible polyurethane foam fabrication plant site is a plant site where pieces of flexible polyurethane...

  1. 40 CFR 63.8782 - Am I subject to this subpart?

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ...) National Emission Standards for Hazardous Air Pollutants: Flexible Polyurethane Foam Fabrication Operations... you own or operate a flexible polyurethane foam fabrication plant site that operates a flame... flexible polyurethane foam fabrication plant site is a plant site where pieces of flexible polyurethane...

  2. 40 CFR 63.8782 - Am I subject to this subpart?

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ...) National Emission Standards for Hazardous Air Pollutants: Flexible Polyurethane Foam Fabrication Operations... you own or operate a flexible polyurethane foam fabrication plant site that operates a flame... flexible polyurethane foam fabrication plant site is a plant site where pieces of flexible polyurethane...

  3. 40 CFR 63.8782 - Am I subject to this subpart?

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ...) National Emission Standards for Hazardous Air Pollutants: Flexible Polyurethane Foam Fabrication Operations... you own or operate a flexible polyurethane foam fabrication plant site that operates a flame... flexible polyurethane foam fabrication plant site is a plant site where pieces of flexible polyurethane...

  4. The Modification of Polyurethane Foams Using New Boroorganic Polyols (II) Polyurethane Foams from Boron-Modified Hydroxypropyl Urea Derivatives

    PubMed Central

    2014-01-01

    The work focuses on research related to determination of application possibility of new, ecofriendly boroorganic polyols in rigid polyurethane foams production. Polyols were obtained from hydroxypropyl urea derivatives esterified with boric acid and propylene carbonate. The influence of esterification type on properties of polyols and next on polyurethane foams properties was determined. Nitrogen and boron impacts on the foams' properties were discussed, for instance, on their physical, mechanical, and electric properties. Boron presence causes improvement of dimensional stability and thermal stability of polyurethane foams. They can be applied even at temperature 150°C. Unfortunately, introducing boron in polyurethanes foams affects deterioration of their water absorption, which increases as compared to the foams that do not contain boron. However, presence of both boron and nitrogen determines the decrease of the foams combustibility. Main impact on the decrease combustibility of the obtained foams has nitrogen presence, but in case of proper boron and nitrogen ratio their synergic activity on the combustibility decrease can be easily seen. PMID:24587721

  5. 40 CFR 63.11415 - What are my compliance dates?

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ...) National Emission Standards for Hazardous Air Pollutants for Flexible Polyurethane Foam Production and... you own or operate an existing slabstock flexible polyurethane foam production affected source, you... or operate an existing molded flexible polyurethane foam affected source, an existing rebond foam...

  6. 40 CFR 63.11415 - What are my compliance dates?

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ...) National Emission Standards for Hazardous Air Pollutants for Flexible Polyurethane Foam Production and... you own or operate an existing slabstock flexible polyurethane foam production affected source, you... or operate an existing molded flexible polyurethane foam affected source, an existing rebond foam...

  7. 40 CFR 63.11415 - What are my compliance dates?

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ...) National Emission Standards for Hazardous Air Pollutants for Flexible Polyurethane Foam Production and... you own or operate an existing slabstock flexible polyurethane foam production affected source, you... or operate an existing molded flexible polyurethane foam affected source, an existing rebond foam...

  8. 40 CFR 63.11415 - What are my compliance dates?

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ...) National Emission Standards for Hazardous Air Pollutants for Flexible Polyurethane Foam Production and... you own or operate an existing slabstock flexible polyurethane foam production affected source, you... or operate an existing molded flexible polyurethane foam affected source, an existing rebond foam...

  9. 40 CFR 63.11415 - What are my compliance dates?

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ...) National Emission Standards for Hazardous Air Pollutants for Flexible Polyurethane Foam Production and... you own or operate an existing slabstock flexible polyurethane foam production affected source, you... or operate an existing molded flexible polyurethane foam affected source, an existing rebond foam...

  10. PUFoam : A novel open-source CFD solver for the simulation of polyurethane foams

    NASA Astrophysics Data System (ADS)

    Karimi, M.; Droghetti, H.; Marchisio, D. L.

    2017-08-01

    In this work a transient three-dimensional mathematical model is formulated and validated for the simulation of polyurethane (PU) foams. The model is based on computational fluid dynamics (CFD) and is coupled with a population balance equation (PBE) to describe the evolution of the gas bubbles/cells within the PU foam. The front face of the expanding foam is monitored on the basis of the volume-of-fluid (VOF) method using a compressible solver available in OpenFOAM version 3.0.1. The solver is additionally supplemented to include the PBE, solved with the quadrature method of moments (QMOM), the polymerization kinetics, an adequate rheological model and a simple model for the foam thermal conductivity. The new solver is labelled as PUFoam and is, for the first time in this work, validated for 12 different mixing-cup experiments. Comparison of the time evolution of the predicted and experimentally measured density and temperature of the PU foam shows the potentials and limitations of the approach.

  11. Design and milling manufacture of polyurethane custom contoured cushions for wheelchair users.

    PubMed

    da Silva, Fabio Pinto; Beretta, Elisa Marangon; Prestes, Rafael Cavalli; Kindlein Junior, Wilson

    2011-01-01

    The design of custom contoured cushions manufactured in flexible polyurethane foams is an option to improve positioning and comfort for people with disabilities that spend most of the day seated in the same position. These surfaces increase the contact area between the seat and the user. This fact contributes to minimise the local pressures that can generate problems like decubitus ulcers. The present research aims at establishing development routes for custom cushion production to wheelchair users. This study also contributes to the investigation of Computer Numerical Control (CNC) machining of flexible polyurethane foams. The proposed route to obtain the customised seat began with acquiring the user's contour in adequate posture through plaster cast. To collect the surface geometry, the cast was three-dimensionally scanned and manipulated in CAD/CAM software. CNC milling parameters such as tools, spindle speeds and feed rates to machine flexible polyurethane foams were tested. These parameters were analysed regarding the surface quality. The best parameters were then tested in a customised seat. The possible dimensional changes generated during foam cutting were analysed through 3D scanning. Also, the customised seat pressure and temperature distribution was tested. The best parameters found for foams with a density of 50kg/cm(3) were high spindle speeds (24000 rpm) and feed rates between 2400-4000mm/min. Those parameters did not generate significant deformities in the machined cushions. The custom contoured cushion satisfactorily increased the contact area between wheelchair and user, as it distributed pressure and heat evenly. Through this study it was possible to define routes for the development and manufacturing of customised seats using direct CNC milling in flexible polyurethane foams. It also showed that custom contoured cushions efficiently distribute pressure and temperature, which is believed to minimise tissue lesions such as pressure ulcers.

  12. DOE Office of Scientific and Technical Information (OSTI.GOV)

    Lu, Wei-Yang

    Foam materials are used to protect sensitive components from impact loading. In order to predict and simulate the foam performance under various loading conditions, a validated foam model is needed and the mechanical properties of foams need to be characterized. Uniaxial compression and tension tests were conducted for different densities of foams under various temperatures and loading rates. Crush stress, tensile strength, and elastic modulus were obtained. A newly developed confined compression experiment provided data for investigating the foam flow direction. A biaxial tension experiment was also developed to explore the damage surface of a rigid polyurethane foam.

  13. Effect of replacing polyol by organosolv and kraft lignin on the property and structure of rigid polyurethane foam.

    PubMed

    Pan, Xuejun; Saddler, Jack N

    2013-01-28

    Lignin is one of the three major components in plant cell walls, and it can be isolated (dissolved) from the cell wall in pretreatment or chemical pulping. However, there is a lack of high-value applications for lignin, and the commonest proposal for lignin is power and steam generation through combustion. Organosolv ethanol process is one of the effective pretreatment methods for woody biomass for cellulosic ethanol production, and kraft process is a dominant chemical pulping method in paper industry. In the present research, the lignins from organosolv pretreatment and kraft pulping were evaluated to replace polyol for producing rigid polyurethane foams (RPFs). Petroleum-based polyol was replaced with hardwood ethanol organosolv lignin (HEL) or hardwood kraft lignin (HKL) from 25% to 70% (molar percentage) in preparing rigid polyurethane foam. The prepared foams contained 12-36% (w/w) HEL or 9-28% (w/w) HKL. The density, compressive strength, and cellular structure of the prepared foams were investigated and compared. Chain extenders were used to improve the properties of the RPFs. It was found that lignin was chemically crosslinked not just physically trapped in the rigid polyurethane foams. The lignin-containing foams had comparable structure and strength up to 25-30% (w/w) HEL or 19-23% (w/w) HKL addition. The results indicated that HEL performed much better in RPFs and could replace more polyol at the same strength than HKL because the former had a better miscibility with the polyol than the latter. Chain extender such as butanediol could improve the strength of lignin-containing RPFs.

  14. Rigid Polyurethane Foams from Lignin Based-Polyols

    NASA Astrophysics Data System (ADS)

    Cateto, Carolina; Barreiro, Filomena; Rodrigues, Alírio; Belgacem, Naceur

    2008-08-01

    Rigid polyurethane (RPU) foams were synthesized using lignin-based polyols obtained by an oxypropylation process. Alcell, Indulin AT, Curan 27-11P and Sarkanda lignins have been oxypropylated using formulations deduced from an optimization study with Alcell. L/PO/C (ratio between lignin, PO and catalyst content) of 30/70/2 and 20/80/5 were used to obtain the desired polyols. The resulting RPU foams were characterized in terms of density, mechanical properties, conductivity and morphology. All Sarkanda lignin based polyols and the 30/70/2 Curan 27-11P polyol were found inadequate for RPU formulations. Alcell and Indulin AT based polyols and the 20/80/5 Curan 27-11P polyol resulted in RPU foams with properties very similar to those obtained from conventional commercial polyols. RPU foams produced with the 30/70/2 Alcell and the 30/70/2 Indulin AT polyols exhibited improved properties compared with those from 20/80/5 based formulations.

  15. Polyurethane rigid foam, a proven thermal insulating material for applications between +130°C and -196°C

    NASA Astrophysics Data System (ADS)

    Demharter, Anton

    Polyurethanes are high molecular weight polymers based on the polyaddition of polyfunctional hydroxyl-group containing compounds and polyisocyanates. A wide variety of properties can be tailored to fulfil the requirements of different applications: soft to hard, plastic, elastic or thermoset, compact or foamed. Compared with other insulating materials, PUR rigid foam is highly competitive. There are five product-related advantages: lowest thermal conductivity, high mechanical and chemical properties at both high and low temperatures, all major international fire safety requirements can be satisfied, the ability to form sandwich structures with various facer materials, and the new generation of PUR is CFC-free and recyclable. Rigid polyurethane foams perform well in most areas of low-temperature insulations. Products in density ranging from approximately 30 to 200 kg m -3 withstand temperatures down to -196°C. Typical applications are: refrigerated vehicles, road and rail tankers, vessels for refrigerated cargo, pipelines, liquid gas tanks for LPG and LNG and cryogenic wind tunnels. The paper presents applications, corresponding properties of the rigid foams used, and also other insulating materials in competition to PUR are discussed.

  16. 40 CFR 63.11414 - Am I subject to this subpart?

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ...) National Emission Standards for Hazardous Air Pollutants for Flexible Polyurethane Foam Production and... that produces flexible polyurethane foam or rebond foam as defined in § 63.1292 of subpart III. (2) You own or operate a flexible polyurethane foam fabrication facility, as defined in § 63.11419. (b) The...

  17. 40 CFR 63.11414 - Am I subject to this subpart?

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ...) National Emission Standards for Hazardous Air Pollutants for Flexible Polyurethane Foam Production and... that produces flexible polyurethane foam or rebond foam as defined in § 63.1292 of subpart III. (2) You own or operate a flexible polyurethane foam fabrication facility, as defined in § 63.11419. (b) The...

  18. 40 CFR 63.11414 - Am I subject to this subpart?

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ...) National Emission Standards for Hazardous Air Pollutants for Flexible Polyurethane Foam Production and... that produces flexible polyurethane foam or rebond foam as defined in § 63.1292 of subpart III. (2) You own or operate a flexible polyurethane foam fabrication facility, as defined in § 63.11419. (b) The...

  19. 40 CFR 63.1290 - Applicability.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... Hazardous Air Pollutants for Flexible Polyurethane Foam Production § 63.1290 Applicability. (a) The provisions of this subpart apply to each new and existing flexible polyurethane foam or rebond foam process... polyurethane or rebond foam; (2) Emits a HAP, except as provided in paragraph (c)(2) of this section; and (3...

  20. 40 CFR 63.11414 - Am I subject to this subpart?

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ...) National Emission Standards for Hazardous Air Pollutants for Flexible Polyurethane Foam Production and... that produces flexible polyurethane foam or rebond foam as defined in § 63.1292 of subpart III. (2) You own or operate a flexible polyurethane foam fabrication facility, as defined in § 63.11419. (b) The...

  1. 40 CFR 63.1290 - Applicability.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... Hazardous Air Pollutants for Flexible Polyurethane Foam Production § 63.1290 Applicability. (a) The provisions of this subpart apply to each new and existing flexible polyurethane foam or rebond foam process... polyurethane or rebond foam; (2) Emits a HAP, except as provided in paragraph (c)(2) of this section; and (3...

  2. 40 CFR 63.1290 - Applicability.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... Hazardous Air Pollutants for Flexible Polyurethane Foam Production § 63.1290 Applicability. (a) The provisions of this subpart apply to each new and existing flexible polyurethane foam or rebond foam process... polyurethane or rebond foam; (2) Emits a HAP, except as provided in paragraph (c)(2) of this section; and (3...

  3. 40 CFR 63.11414 - Am I subject to this subpart?

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ...) National Emission Standards for Hazardous Air Pollutants for Flexible Polyurethane Foam Production and... that produces flexible polyurethane foam or rebond foam as defined in § 63.1292 of subpart III. (2) You own or operate a flexible polyurethane foam fabrication facility, as defined in § 63.11419. (b) The...

  4. Polyurethane Masks Large Areas in Electroplating

    NASA Technical Reports Server (NTRS)

    Beasley, J. L.

    1985-01-01

    Polyurethane foam provides effective mask in electroplating of copper or nickel. Thin layer of Turco maskant painted on area to be masked: Layer ensures polyurethane foam removed easily after served its purpose. Component A, isocyanate, and component B, polyol, mixed together and brushed or sprayed on mask area. Mixture reacts, yielding polyurethane foam. Foam prevents deposition of nickel or copper on covered area. New method saves time, increases productivity and uses less material than older procedures.

  5. Experimental study on cryogenic moisture uptake in polyurethane foam insulation material

    NASA Astrophysics Data System (ADS)

    Zhang, X. B.; Yao, L.; Qiu, L. M.; Gan, Z. H.; Yang, R. P.; Ma, X. J.; Liu, Z. H.

    2012-12-01

    Rigid foam is widely used to insulate cryogenic tanks, in particular for space launch vehicles due to its lightweight, mechanical strength and thermal-insulating performance. Up to now, little information is available on the intrusion of moisture into the material under cryogenic conditions, which will bring substantial additional weight for the space vehicles at lift-off. A cryogenic moisture uptake apparatus has been designed and fabricated to measure the amount of water uptake into the polyurethane foam. One side of the specimen is exposed to an environment with high humidity and ambient temperature, while the other with cryogenic temperature at approximately 78 K. A total of 16 specimens were tested for up to 24 h to explore the effects of the surface thermal protection layer, the foam thickness, exposed time, the butt joints, and the material density on water uptake of the foam. The results are constructive for the applications of the foam to the cryogenic insulation system in space launch vehicles.

  6. Experimental Characterization of the Energy Absorption of Functionally Graded Foam Filled Tubes Under Axial Crushing Loads

    NASA Astrophysics Data System (ADS)

    Ebrahimi, Saeed; Vahdatazad, Nader; Liaghat, Gholamhossein

    2018-03-01

    This paper deals with the energy absorption characterization of functionally graded foam (FGF) filled tubes under axial crushing loads by experimental method. The FGF tubes are filled axially by gradient layers of polyurethane foams with different densities. The mechanical properties of the polyurethane foams are firstly obtained from axial compressive tests. Then, the quasi-static compressive tests are carried out for empty tubes, uniform foam filled tubes and FGF filled tubes. Before to present the experimental test results, a nonlinear FEM simulation of the FGF filled tube is carried out in ABAQUS software to gain more insight into the crush deformation patterns, as well as the energy absorption capability of the FGF filled tube. A good agreement between the experimental and simulation results is observed. Finally, the results of experimental test show that an FGF filled tube has excellent energy absorption capacity compared to the ordinary uniform foam-filled tube with the same weight.

  7. Response of Polyurethane to Shock Waves: An Experimental Investigation

    NASA Astrophysics Data System (ADS)

    Jayaram, V.; Rao, Keshava Subba; Thanganayaki, N.; Kumara, H. K. T.; Reddy, K. P. J.

    Formation of polyurethane (PU) in vacuum environment and controlling density of polyurethane foams are the present day challenges. Polyurethane exists in numerous forms ranging from flexible to rigid and lightweight foams to tough, stiff elastomers [1]. PU can be used to produce lightweight foams for insulation or hard rubber used as wheels to transport heavy loads and it can be used in high pressure applications. The largest volumes of commercial PU elastomers are made from toluene diisocyanate (TDI) or diphenylmethane-4, 4'-diisocyanate (MDI) [2]. Linear polyurethanes can be processed into final products by any of the standard thermoplastic processes (injection molding, extrusion, thermoforming) as well as by low pressure cast processes in presence of catalysts. Tin, tetrabutyl titanate and zirconium chelates are few effective catalysts used to produce polyurethane for particular application [3]. Thermoset elastomers are formed due to irreversible cross-links, when polymers are chemically cured. Highly porous biodegradable PU was synthesized by thermally induced phase separation technique used in tissue engineering and also in bio-degradable based fluids [4]. Properties of PU like hardness, stress/strain modulus, tear strength etc, was determine using ASTM (American Society for Testing and Materials) standard methods. PU possesses extremely high mechanical properties, excellent abrasion, tear and extrusion resistance. It has outstanding low-temperature limit (-600C) and high temperature limit up to (1500C).

  8. A study of aerosol entrapment and the influence of wind speed, chamber design and foam density on polyurethane foam passive air samplers used for persistent organic pollutants.

    PubMed

    Chaemfa, Chakra; Wild, Edward; Davison, Brian; Barber, Jonathan L; Jones, Kevin C

    2009-06-01

    Polyurethane foam disks are a cheap and versatile tool for sampling persistent organic pollutants (POPs) from the air in ambient, occupational and indoor settings. This study provides important background information on the ways in which the performance of these commonly used passive air samplers may be influenced by the key environmental variables of wind speed and aerosol entrapment. Studies were performed in the field, a wind tunnel and with microscopy techniques, to investigate deployment conditions and foam density influence on gas phase sampling rates (not obtained in this study) and aerosol trapping. The study showed: wind speed inside the sampler is greater on the upper side of the sampling disk than the lower side and tethered samplers have higher wind speeds across the upper and lower surfaces of the foam disk at a wind speed > or = 4 m/s; particles are trapped on the foam surface and within the body of the foam disk; fine (<1 um) particles can form clusters of larger size inside the foam matrix. Whilst primarily designed to sample gas phase POPs, entrapment of particles ensures some 'sampling' of particle bound POPs species, such as higher molecular weight PAHs and PCDD/Fs. Further work is required to investigate how quantitative such entrapment or 'sampling' is under different ambient conditions, and with different aerosol sizes and types.

  9. IDENTIFICATION OF CFC AND HCFC SUBSTITUTES FOR BLOWING POLYURETHANE FOAM INSULATION PRODUCTS

    EPA Science Inventory

    The report gives results of a cooperative effort to identiry chlorofluorocarbons and hydrochlorofluorocarbon substitutes for blowing polyurethane foam insulation products. The substantial ongoing effort is identifying third-generation blowing agets for polyurethane foams to repla...

  10. 40 CFR 63.1307 - Recordkeeping requirements.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ...) National Emission Standards for Hazardous Air Pollutants for Flexible Polyurethane Foam Production § 63... section. Each flexible polyurethane foam slabstock source complying with the emission point specific... this section. Each flexible polyurethane foam slabstock source complying with the source-wide...

  11. 40 CFR 63.1307 - Recordkeeping requirements.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ...) National Emission Standards for Hazardous Air Pollutants for Flexible Polyurethane Foam Production § 63... section. Each flexible polyurethane foam slabstock source complying with the emission point specific... this section. Each flexible polyurethane foam slabstock source complying with the source-wide...

  12. Effect of replacing polyol by organosolv and kraft lignin on the property and structure of rigid polyurethane foam

    PubMed Central

    2013-01-01

    Background Lignin is one of the three major components in plant cell walls, and it can be isolated (dissolved) from the cell wall in pretreatment or chemical pulping. However, there is a lack of high-value applications for lignin, and the commonest proposal for lignin is power and steam generation through combustion. Organosolv ethanol process is one of the effective pretreatment methods for woody biomass for cellulosic ethanol production, and kraft process is a dominant chemical pulping method in paper industry. In the present research, the lignins from organosolv pretreatment and kraft pulping were evaluated to replace polyol for producing rigid polyurethane foams (RPFs). Results Petroleum-based polyol was replaced with hardwood ethanol organosolv lignin (HEL) or hardwood kraft lignin (HKL) from 25% to 70% (molar percentage) in preparing rigid polyurethane foam. The prepared foams contained 12-36% (w/w) HEL or 9-28% (w/w) HKL. The density, compressive strength, and cellular structure of the prepared foams were investigated and compared. Chain extenders were used to improve the properties of the RPFs. Conclusions It was found that lignin was chemically crosslinked not just physically trapped in the rigid polyurethane foams. The lignin-containing foams had comparable structure and strength up to 25-30% (w/w) HEL or 19-23% (w/w) HKL addition. The results indicated that HEL performed much better in RPFs and could replace more polyol at the same strength than HKL because the former had a better miscibility with the polyol than the latter. Chain extender such as butanediol could improve the strength of lignin-containing RPFs. PMID:23356502

  13. Fiber glass prevents cracking of polyurethane foam insulation on cryogenic vessels

    NASA Technical Reports Server (NTRS)

    Forge, D. A.

    1968-01-01

    Fiber glass material, placed between polyurethane foam insulation and the outer surfaces of cryogenic vessels, retains its resilience at cryogenic temperatures and provides an expansion layer between the metal surfaces and the polyurethane foam, preventing cracking of the latter.

  14. Properties of polyurethane foam/coconut coir fiber as a core material and as a sandwich composites component

    NASA Astrophysics Data System (ADS)

    Azmi, M. A.; Abdullah, H. Z.; Idris, M. I.

    2013-12-01

    This research focuses on the fabrication and characterization of sandwich composite panels using glass fiber composite skin and polyurethane foam reinforced coconut coir fiber core. The main objectives are to characterize the physical and mechanical properties and to elucidate the effect of coconut coir fibers in polyurethane foam cores and sandwich composite panels. Coconut coir fibers were used as reinforcement in polyurethane foams in which later were applied as the core in sandwich composites ranged from 5 wt% to 20 wt%. The physical and mechanical properties found to be significant at 5 wt% coconut coir fiber in polyurethane foam cores as well as in sandwich composites. It was found that composites properties serve better in sandwich composites construction.

  15. Damage Caused to Polyurethane Foams by Aging, Simulated Sunlight Exposure, Heat and Fire

    DTIC Science & Technology

    1984-07-01

    vented configuration ............ .................. 11 4 Sample of the tan-colored solid formed upon pyrolysis of blue foam ..... .............. .. 21...54 26 Infrared absorption spectrum of the solid, tan-colored pyrolysis product formed from blue polyurethane foam ..... .............. .. 55 27...Infrared absorption spectrum of the liquid, brown-colored pyrolysis product formed from blue polyurethane foam ..... .............. .. 56 28 Fuel vent

  16. Modeling Manufacturing Impacts on Aging and Reliability of Polyurethane Foams

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Rao, Rekha R.; Roberts, Christine Cardinal; Mondy, Lisa Ann

    Polyurethane is a complex multiphase material that evolves from a viscous liquid to a system of percolating bubbles, which are created via a CO2 generating reaction. The continuous phase polymerizes to a solid during the foaming process generating heat. Foams introduced into a mold increase their volume up to tenfold, and the dynamics of the expansion process may lead to voids and will produce gradients in density and degree of polymerization. These inhomogeneities can lead to structural stability issues upon aging. For instance, structural components in weapon systems have been shown to change shape as they age depending on theirmore » molding history, which can threaten critical tolerances. The purpose of this project is to develop a Cradle-to-Grave multiphysics model, which allows us to predict the material properties of foam from its birth through aging in the stockpile, where its dimensional stability is important.« less

  17. Evaluation of the Efficacy of Highly Hydrophilic Polyurethane Foam Dressing in Treating a Diabetic Foot Ulcer.

    PubMed

    Jung, Jae-A; Yoo, Ki-Hyun; Han, Seung-Kyu; Dhong, Eun-Sang; Kim, Woo-Kyung

    2016-12-01

    To demonstrate the efficacy of a highly hydrophilic polyurethane foam dressing in the treatment of diabetic ulcers. Diabetic foot ulcers often pose a difficult treatment problem. Polyurethane foam dressings have been used worldwide to accelerate wound healing, but only a few clinical studies demonstrate the effect of foam dressing on the healing of diabetic ulcers. Medical records of 1342 patients with diabetic ulcers who were admitted and treated at the authors' institution were reviewed. A total of 208 patients met the study's inclusion criteria. Of these 208 patients, 137 were treated with a highly hydrophilic polyurethane foam dressing, and 71 were treated with saline gauze (control group). Except for the application of polyurethane foam dressing, the treatment method was identical for patients in both groups. The wound healing outcomes of the 2 groups were compared. Complete wound healing occurred in 87 patients (63.5%) in the polyurethane foam dressing group and in 28 patients (39.4%) in the control group within 12 weeks (P < .05, X test). The mean percentage of wound area reduction in both groups was statistically significant (P < .05, Mann-Whitney U test). The mean time required for complete closure in patients who achieved complete healing within 12 weeks was 6.2 (SD, 3.4) weeks and 7.3 (SD, 2.6) weeks in the polyurethane foam dressing and control groups, respectively (P < .05, Mann-Whitney U test). These results indicate that the highly hydrophilic polyurethane foam dressing may provide an effective treatment strategy for diabetic foot ulcers.

  18. DOE Office of Scientific and Technical Information (OSTI.GOV)

    Mondy, Lisa Ann; Rao, Rekha Ranjana; Shelden, Bion

    We are developing computational models to elucidate the expansion and dynamic filling process of a polyurethane foam, PMDI. The polyurethane of interest is chemically blown, where carbon dioxide is produced via the reaction of water, the blowing agent, and isocyanate. The isocyanate also reacts with polyol in a competing reaction, which produces the polymer. Here we detail the experiments needed to populate a processing model and provide parameters for the model based on these experiments. The model entails solving the conservation equations, including the equations of motion, an energy balance, and two rate equations for the polymerization and foaming reactions,more » following a simplified mathematical formalism that decouples these two reactions. Parameters for the polymerization kinetics model are reported based on infrared spectrophotometry. Parameters describing the gas generating reaction are reported based on measurements of volume, temperature and pressure evolution with time. A foam rheology model is proposed and parameters determined through steady-shear and oscillatory tests. Heat of reaction and heat capacity are determined through differential scanning calorimetry. Thermal conductivity of the foam as a function of density is measured using a transient method based on the theory of the transient plane source technique. Finally, density variations of the resulting solid foam in several simple geometries are directly measured by sectioning and sampling mass, as well as through x-ray computed tomography. These density measurements will be useful for model validation once the complete model is implemented in an engineering code.« less

  19. 40 CFR 63.11417 - What are the compliance requirements for new and existing sources?

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... Flexible Polyurethane Foam Production and Fabrication Area Sources Standards and Compliance Requirements... a slabstock flexible polyurethane foam production affected source, you must comply with the... affected source, or a loop slitter at a flexible polyurethane foam fabrication affected source you must...

  20. 40 CFR 63.1290 - Applicability.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... Standards for Hazardous Air Pollutants for Flexible Polyurethane Foam Production § 63.1290 Applicability. (a) The provisions of this subpart apply to each new and existing flexible polyurethane foam or rebond...) Produces flexible polyurethane or rebond foam; (2) Emits a HAP, except as provided in paragraph (c)(2) of...

  1. 40 CFR 63.11417 - What are the compliance requirements for new and existing sources?

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... Flexible Polyurethane Foam Production and Fabrication Area Sources Standards and Compliance Requirements... a slabstock flexible polyurethane foam production affected source, you must comply with the... affected source, or a loop slitter at a flexible polyurethane foam fabrication affected source you must...

  2. 40 CFR 63.11417 - What are the compliance requirements for new and existing sources?

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... Flexible Polyurethane Foam Production and Fabrication Area Sources Standards and Compliance Requirements... a slabstock flexible polyurethane foam production affected source, you must comply with the... affected source, or a loop slitter at a flexible polyurethane foam fabrication affected source you must...

  3. 40 CFR 63.11417 - What are the compliance requirements for new and existing sources?

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... Flexible Polyurethane Foam Production and Fabrication Area Sources Standards and Compliance Requirements... a slabstock flexible polyurethane foam production affected source, you must comply with the... affected source, or a loop slitter at a flexible polyurethane foam fabrication affected source you must...

  4. 40 CFR 63.11417 - What are the compliance requirements for new and existing sources?

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... Flexible Polyurethane Foam Production and Fabrication Area Sources Standards and Compliance Requirements... a slabstock flexible polyurethane foam production affected source, you must comply with the... affected source, or a loop slitter at a flexible polyurethane foam fabrication affected source you must...

  5. 40 CFR 63.1290 - Applicability.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... Standards for Hazardous Air Pollutants for Flexible Polyurethane Foam Production § 63.1290 Applicability. (a) The provisions of this subpart apply to each new and existing flexible polyurethane foam or rebond...) Produces flexible polyurethane or rebond foam; (2) Emits a HAP, except as provided in paragraph (c)(2) of...

  6. 40 CFR 63.11419 - What definitions apply to this subpart?

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... (CONTINUED) National Emission Standards for Hazardous Air Pollutants for Flexible Polyurethane Foam...; § 63.8830 of subpart MMMMM; § 63.2 of subpart A; and in this section as follows: Flexible polyurethane foam fabrication facility means a facility where pieces of flexible polyurethane foam are cut, bonded...

  7. 40 CFR 63.11419 - What definitions apply to this subpart?

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... (CONTINUED) National Emission Standards for Hazardous Air Pollutants for Flexible Polyurethane Foam...; § 63.8830 of subpart MMMMM; § 63.2 of subpart A; and in this section as follows: Flexible polyurethane foam fabrication facility means a facility where pieces of flexible polyurethane foam are cut, bonded...

  8. 40 CFR 63.11419 - What definitions apply to this subpart?

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... (CONTINUED) National Emission Standards for Hazardous Air Pollutants for Flexible Polyurethane Foam...; § 63.8830 of subpart MMMMM; § 63.2 of subpart A; and in this section as follows: Flexible polyurethane foam fabrication facility means a facility where pieces of flexible polyurethane foam are cut, bonded...

  9. 40 CFR 63.11419 - What definitions apply to this subpart?

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... (CONTINUED) National Emission Standards for Hazardous Air Pollutants for Flexible Polyurethane Foam...; § 63.8830 of subpart MMMMM; § 63.2 of subpart A; and in this section as follows: Flexible polyurethane foam fabrication facility means a facility where pieces of flexible polyurethane foam are cut, bonded...

  10. 40 CFR 63.11419 - What definitions apply to this subpart?

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... (CONTINUED) National Emission Standards for Hazardous Air Pollutants for Flexible Polyurethane Foam...; § 63.8830 of subpart MMMMM; § 63.2 of subpart A; and in this section as follows: Flexible polyurethane foam fabrication facility means a facility where pieces of flexible polyurethane foam are cut, bonded...

  11. An overview of polyurethane foams in higher specification foam mattresses.

    PubMed

    Soppi, Esa; Lehtiö, Juha; Saarinen, Hannu

    2015-02-01

    Soft polyurethane foams exist in thousands of grades and constitute essential components of hospital mattresses. For pressure ulcer prevention, the ability of foams to control the immersion and envelopment of patients is essential. Higher specification foam mattresses (i.e., foam mattresses that relieve pressure via optimum patient immersion and envelopment while enabling patient position changes) are claimed to be more effective for preventing pressure ulcers than standard mattresses. Foam grade evaluations should include resiliency, density, hardness, indentation force/load deflection, progressive hardness, tensile strength, and elongation along with essential criteria for higher specification foam mattresses. Patient-specific requirements may include optimal control of patient immersion and envelopment. Mattress cover characteristics should include breathability, impermeability to fluids, and fire safety and not affect mattress function. Additional determinations such as hardness are assessed according to the guidelines of the American Society for Testing and Materials and the International Organization for Standardization. At this time, no single foam grade provides an optimal combination of the above key requirements, but the literature suggests a combination of at least 2 foams may create an optimal higher specification foam mattress for pressure ulcer prevention. Future research and the development of product specification accuracy standards are needed to help clinicians make evidence-based decisions about mattress use.

  12. Polyurethane-Foam Maskant

    NASA Technical Reports Server (NTRS)

    Bodemeijer, R.

    1985-01-01

    Brown wax previously used to mask hardware replaced with polyurethane foam in electroplating and electroforming operations. Foam easier to apply and remove than wax and does not contaminate electrolytes.

  13. 40 CFR 63.11416 - What are the standards for new and existing sources?

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... polyurethane foam production affected source, you must meet the requirements in paragraph (b) of this section... in paragraph (d) of this section. If you own or operate a flexible polyurethane foam fabrication... a new or existing slabstock polyurethane foam production affected source, you must comply with the...

  14. 40 CFR 63.11416 - What are the standards for new and existing sources?

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... polyurethane foam production affected source, you must meet the requirements in paragraph (b) of this section... in paragraph (d) of this section. If you own or operate a flexible polyurethane foam fabrication... a new or existing slabstock polyurethane foam production affected source, you must comply with the...

  15. 40 CFR 63.11416 - What are the standards for new and existing sources?

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... polyurethane foam production affected source, you must meet the requirements in paragraph (b) of this section... in paragraph (d) of this section. If you own or operate a flexible polyurethane foam fabrication... a new or existing slabstock polyurethane foam production affected source, you must comply with the...

  16. 40 CFR 63.11416 - What are the standards for new and existing sources?

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... polyurethane foam production affected source, you must meet the requirements in paragraph (b) of this section... in paragraph (d) of this section. If you own or operate a flexible polyurethane foam fabrication... a new or existing slabstock polyurethane foam production affected source, you must comply with the...

  17. 40 CFR 63.11416 - What are the standards for new and existing sources?

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... polyurethane foam production affected source, you must meet the requirements in paragraph (b) of this section... in paragraph (d) of this section. If you own or operate a flexible polyurethane foam fabrication... a new or existing slabstock polyurethane foam production affected source, you must comply with the...

  18. DOE Office of Scientific and Technical Information (OSTI.GOV)

    Neilsen, Michael K.; Lu, Wei-Yang; Scherzinger, William M.

    Numerous experiments were performed to characterize the mechanical response of several different rigid polyurethane foams (FR3712, PMDI10, PMDI20, and TufFoam35) to large deformation. In these experiments, the effects of load path, loading rate, and temperature were investigated. Results from these experiments indicated that rigid polyurethane foams exhibit significant volumetric and deviatoric plasticity when they are compressed. Rigid polyurethane foams were also found to be very strain-rate and temperature dependent. These foams are also rather brittle and crack when loaded to small strains in tension or to larger strains in compression. Thus, a new Unified Creep Plasticity Damage (UCPD) model wasmore » developed and implemented into SIERRA with the name Foam Damage to describe the mechanical response of these foams to large deformation at a variety of temperatures and strain rates. This report includes a description of recent experiments and experimental findings. Next, development of a UCPD model for rigid, polyurethane foams is described. Selection of material parameters for a variety of rigid polyurethane foams is then discussed and finite element simulations with the new UCPD model are compared with experimental results to show behavior that can be captured with this model.« less

  19. Effect of aluminum phosphate on alkaline phosphatase activity of polyurethane foam immobilized cyanobacteria.

    PubMed

    Ramalingam, N; Prasanna, B Gowtham

    2006-09-01

    The impact of insoluble phosphorus such as aluminum and rock phosphate on alkaline phosphatase activity of polyurethane foam immobilized cyanobacteria was assessed. Polyurethane foam immobilized Nodularia recorded the highest alkaline phosphatase activity of 9.04 (m. mol p-nitrophenol released h(-1) mg(-1) protein) in vitro. A higher concentration of aluminum phosphate was recorded a 25% reduction in alkaline phosphatase activity, ammonia content, and available phosphorus in culture filtrate of polyurethane foam immobilized cyanobacteria. In general, immobilized cyanobacteria exhibited a higher alkaline phosphatase activity in rock phosphate than aluminum phosphate.

  20. The effect of negative pressure wound therapy with antibacterial dressings or antiseptics on an in vitro wound model.

    PubMed

    Matiasek, J; Domig, K J; Djedovic, G; Babeluk, R; Assadian, O

    2017-05-02

    The aim of this study was to investigate the bacterial bioburden in experimental in vitro wounds during the application of conventional negative pressure wound therapy (NPWT), with and without antimicrobial dressings (polyhexanide, silver), against NPWT instillation of octenidine. Experimental wounds produced in an in vitro porcine wound model were homogenously contaminated with bacterial suspension and treated with NPWT and different options. Group A: non-antimicrobial polyurethane foam dressing; group B: antimicrobial polyurethane foam dressing containing silver; group C: antimicrobial gauze dressing containing polyhexanide; group D: non-antimicrobial polyurethane foam dressing intermittently irrigated with octenidine; group E: negative control (non-antimicrobial polyurethane foam dressing without NPWT). Standard biopsies were harvested after 24 and 28 hours. This study demonstrated that the use of NPWT with intermitted instillation of octenidine (group D) or application of silver-based polyurethane foam dressings (group B) is significantly superior against Staphylococcus aureus colonisation in experimental wounds compared with non-antimicrobial polyurethane foam dressing (group A) after 48 hours. Surprisingly, the polyhexanide-based dressing (group C) used in this model showed no statistical significant effect compared with the control group (group E) after 24 or 48 hours of treatment. Both intermitted instillation of octenidine and silver-based dressings in standard NPWT were significantly superior compared with non-antimicrobial polyurethane foam dressings or PHMB coated gauze dressing after 48 hours.

  1. Defense Industrial Base Capabilities Study: Protection

    DTIC Science & Technology

    2004-12-01

    Polyurethane Foam (RPF). 2) The Department should establish an Industrial Base Investment Fund to provide better on-ramps for production-ready...Sweep; − Rigid Polyurethane Foam (RPF). RECOMMENDATION 2 The Department should establish an Industrial Base Investment Fund (IBIF) to provide...Reactive RF Jamming 15. Expendable Programmable Acoustic Decoy 16. Rigid Polyurethane Foam 17. Towed Fabric Balloon Pressure Sweep 18. Chemical

  2. Time-dependent crashworthiness of polyurethane foam

    NASA Astrophysics Data System (ADS)

    Basit, Munshi Mahbubul; Cheon, Seong Sik

    2018-05-01

    Time-dependent stress-strain relationship as well as crashworthiness of polyurethane foam was investigated under constant impact energy with different velocities, considering inertia and strain-rate effects simultaneously during the impact testing. Even though the impact energies were same, the percentage in increase in densification strain due to higher impact velocities was found, which yielded the wider plateau region, i.e. growth in crashworthiness. This phenomenon is analyzed by the microstructure of polyurethane foam obtained from scanning electron microscopy. The equations, coupled with the Sherwood-Frost model and the impulse-momentum theory, were employed to build the constitutive equation of the polyurethane foam and calculate energy absorption capacity of the foam. The nominal stress-strain curves obtained from the constitutive equation were compared with results from impact tests and were found to be in good agreement. This study is dedicated to guiding designer use polyurethane foam in crashworthiness structures such as an automotive bumper system by providing crashworthiness data, determining the crush mode, and addressing a mathematical model of the crashworthiness.

  3. Fracture Toughness Evaluation of Space Shuttle External Tank Thermal Protection System Polyurethane Foam Insulation Materials

    NASA Technical Reports Server (NTRS)

    McGill, Preston; Wells, Doug; Morgan, Kristin

    2006-01-01

    Experimental evaluation of the basic fracture properties of Thermal Protection System (TPS) polyurethane foam insulation materials was conducted to validate the methodology used in estimating critical defect sizes in TPS applications on the Space Shuttle External Fuel Tank. The polyurethane foam found on the External Tank (ET) is manufactured by mixing liquid constituents and allowing them to react and expand upwards - a process which creates component cells that are generally elongated in the foam rise direction and gives rise to mechanical anisotropy. Similarly, the application of successive foam layers to the ET produces cohesive foam interfaces (knitlines) which may lead to local variations in mechanical properties. This study reports the fracture toughness of BX-265, NCFI 24-124, and PDL-1034 closed-cell polyurethane foam as a function of ambient and cryogenic temperatures and knitline/cellular orientation at ambient pressure.

  4. Effect of the carbonyl iron particles on acoustic absorption properties of magnetic polyurethane foam

    NASA Astrophysics Data System (ADS)

    Geng, Jialu; Wang, Caiping; Zhu, Honglang; Wang, Xiaojie

    2018-03-01

    Elastomeric matrix embedded with magnetic micro-sized particles has magnetically controllable properties, which has been investigated extensively in the last decades. In this study we develop a new magnetically controllable elastomeric material for acoustic applications at lower frequencies. The soft polyurethane foam is used as matrix material due to its extraordinary elastic and acoustic absorption properties. One-step method is used to synthesize polyurethane foam, in which all components including polyether polyols 330N, MDI, deionized water, silicone oil, carbonyl iron particle (CIP) and catalyst are put into one container for curing. Changing any component can induce the change of polyurethane foam's properties, such as physical and acoustic properties. The effect of the content of MDI on acoustic absorption is studied. The CIPs are aligned under extra magnetic field during the foaming process. And the property of polyurethane foam with aligned CIPs is also investigated. Scanning electron microscope (SEM) is used to observe the structure of pore and particle-chain. The two-microphone impedance tube and the transfer function method are used to test acoustic absorption property of the magnetic foams.

  5. In vitro analysis of polyurethane foam as a topical hemostatic agent.

    PubMed

    Broekema, Ferdinand I; van Oeveren, Wim; Zuidema, Johan; Visscher, Susan H; Bos, Rudolf R M

    2011-04-01

    Topical hemostatic agents can be used to treat problematic bleedings in patients who undergo surgery. Widely used are the collagen- and gelatin-based hemostats. This study aimed to develop a fully synthetic, biodegradable hemostatic agent to avoid exposure to animal antigens. In this in vitro study the suitability of different newly developed polyurethane-based foams as a hemostatic agent has been evaluated and compared to commonly used agents. An experimental in vitro test model was used in which human blood flowed through the test material. Different modified polyurethane foams were compared to collagen and gelatin. The best coagulation was achieved with collagen. The results of the polyurethane foam improved significantly by increasing the amount of polyethylene glycol. Therefore, the increase of the PEG concentration seems a promising approach. Additional in vivo studies will have to be implemented to assess the application of polyurethane foam as a topical hemostatic agent.

  6. Fire retardant foams developed to suppress fuel fires

    NASA Technical Reports Server (NTRS)

    Fish, R.; Gilwee, W. J.; Parker, J. A.; Riccitiello, S. R.

    1968-01-01

    Heat insulating polyurethane foam retards and suppresses fuel fires. Uniformly dispersed in the foam is a halogenated polymer capable of splitting off hydrogen halide upon heating and charring of the polyurethane.

  7. Flexible Foam Model.

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Neilsen, Michael K.; Lu, Wei-Yang; Werner, Brian T.

    Experiments were performed to characterize the mechanical response of a 15 pcf flexible polyurethane foam to large deformation at different strain rates and temperatures. Results from these experiments indicated that at room temperature, flexible polyurethane foams exhibit significant nonlinear elastic deformation and nearly return to their original undeformed shape when unloaded. However, when these foams are cooled to temperatures below their glass transition temperature of approximately -35 o C, they behave like rigid polyurethane foams and exhibit significant permanent deformation when compressed. Thus, a new model which captures this dramatic change in behavior with temperature was developed and implemented intomore » SIERRA with the name Flex_Foam to describe the mechanical response of both flexible and rigid foams to large deformation at a variety of temperatures and strain rates. This report includes a description of recent experiments. Next, development of the Flex Foam model for flexible polyurethane and other flexible foams is described. Selection of material parameters are discussed and finite element simulations with the new Flex Foam model are compared with experimental results to show behavior that can be captured with this new model.« less

  8. Aerial release of bacteria from cot mattress materials and the sudden infant death syndrome.

    PubMed

    Sherburn, R E; Jenkins, R O

    2005-01-01

    To investigate aerial release of bacteria from used cot mattresses and to assess factors that may influence this process. Movement on used mattresses, simulating that of an infant's head, significantly enhanced aerial release of naturally acquired bacteria from the polyurethane foams (total count data, P = 0.008; Staphylococcus aureus, P = 0.004) or from polyvinyl chloride covers (total count data, P = 0.001). Aerial release of naturally acquired bacteria from used cot mattresses showed high variability and was poorly correlated (R2 < or = 0.294) with bacterial cell density within the materials. In experiments involving inoculation of S. aureus and Escherichia coli onto the polyurethane of unused cot mattresses, aerial release of the species correlated well (R2 > or = 0.950) with inoculation density when simulated infant head movement was applied. Aerial release of these bacterial species from the material decreased with increase in width or aqueous content of the material, and was lower from polyurethane foam of a used cot mattress. Simulated infant movement and mattress related factors influence aerial release of bacteria from cot mattress materials. With simulated infant movement on cot mattress polyurethane foam, levels of airborne bacteria above the material are proportional to bacterial population levels inoculated onto the material. Cot mattresses harbouring relatively high levels of naturally acquired toxigenic bacteria, such as S. aureus, could pose a relatively high risk of infection to the infant's respiratory tract through increased aerial contamination. This has impact in the context of recent findings on cot mattress related risk factors for sudden infant death syndrome.

  9. Design and performance of a trickle-bed bioreactor with immobilized hybridoma cells.

    PubMed

    Phillips, H A; Scharer, J M; Bols, N C; Moo-Young, M

    1992-01-01

    A trickle-bed system employing inert matrices of vermiculite or polyurethane foam packed in the downcomer section of a split-flow air-lift reactor has been developed for hybridoma culture to enhance antibody productivity. This quiescent condition favoured occlusion and allowed the cells to achieve densities twelve fold greater (12.8 x 10(6) cells/ml reactor for polyurethane foam) than in free cell suspension. The reactor was operated in a cyclic batch mode whereby defined volumes of medium were periodically withdrawn and replaced with equal volumes of fresh medium. The pH of the medium was used as the indicator of the feeding schedule. Glucose, lactate and ammonia concentrations reached a stationary value after 5 days. With vermiculite packing, a monoclonal antibody (MAb) concentration of 2.4 mg/l was achieved after 12 days. The MAb concentration declined then increased to a value of 1.8 mg/l. In the polyurethane foam average monoclonal antibody (MAb) concentrations reached a stationary value of 1.1 mg/l in the first 20 days and increased to a new stationary state value of 2.1 mg/l for the remainder of the production. MAb productivity in the trickle-bed reactor was 0.3 mg/l.d (polyurethane foam) and 0.18 mg/l.d (vermiculite) in comparison to 0.12 mg/l.d for free cell suspension. This trickle-bed system seems to be an attractive way of increasing MAb productivity in culture.

  10. Bio-based Polymer Foam from Soyoil

    NASA Astrophysics Data System (ADS)

    Bonnaillie, Laetitia M.; Wool, Richard P.

    2006-03-01

    The growing bio-based polymeric foam industry is presently lead by plant oil-based polyols for polyurethanes and starch foams. We developed a new resilient, thermosetting foam system with a bio-based content higher than 80%. The acrylated epoxidized soybean oil and its fatty acid monomers is foamed with pressurized carbon dioxide and cured with free-radical initiators. The foam structure and pore dynamics are highly dependent on the temperature, viscosity and extent of reaction. Low-temperature cure hinds the destructive pore coalescence and the application of a controlled vacuum results in foams with lower densities ˜ 0.1 g/cc, but larger cells. We analyze the physics of foam formation and stability, as well as the structure and mechanical properties of the cured foam using rigidity percolation theory. The parameters studied include temperature, vacuum applied, and cross-link density. Additives bring additional improvements: nucleating agents and surfactants help produce foams with a high concentration of small cells and low bulk density. Hard and soft thermosetting foams with a bio content superior to 80% are successfully produced and tested. Potential applications include foam-core composites for hurricane-resistant housing, structural reinforcement for windmill blades, and tissue scaffolds.

  11. Polyurethane foams obtained from residues of PET manufacturing and modified with carbon nanotubes

    NASA Astrophysics Data System (ADS)

    Stiebra, L.; Cabulis, U.; Knite, M.

    2016-04-01

    In this work we report the preparation of rigid microcellular polyurethane/carbon nanotube nanocomposites with different CNT loadings (0.09-0.46%) and various isocyanate indexes (110-260). Water was used as a blowing agent for samples. Density of all obtained samples - 200 ± 10 kg/m3. Electrical properties, as well as heat conductivity, cellular structure and mechanical properties of these nanocomposites were investigated.

  12. Detection of halogenated flame retardants in polyurethane foam by particle induced X-ray emission

    NASA Astrophysics Data System (ADS)

    Maley, Adam M.; Falk, Kyle A.; Hoover, Luke; Earlywine, Elly B.; Seymour, Michael D.; DeYoung, Paul A.; Blum, Arlene; Stapleton, Heather M.; Peaslee, Graham F.

    2015-09-01

    A novel application of particle-induced X-ray emission (PIXE) has been developed to detect the presence of chlorinated and brominated flame retardant chemicals in polyurethane foams. Traditional Gas Chromatography-Mass Spectrometry (GC-MS) methods for the detection and identification of halogenated flame retardants in foams require extensive sample preparation and data acquisition time. The elemental analysis of the halogens in polyurethane foam performed by PIXE offers the opportunity to identify the presence of halogenated flame retardants in a fraction of the time and sample preparation cost. Through comparative GC-MS and PIXE analysis of 215 foam samples, excellent agreement between the two methods was obtained. These results suggest that PIXE could be an ideal rapid screening method for the presence of chlorinated and brominated flame retardants in polyurethane foams.

  13. Center for the Polyurethanes Industry summary of unpublished industrial hygiene studies related to the evaluation of emissions of spray polyurethane foam insulation.

    PubMed

    Wood, Richard D

    2017-09-01

    Spray polyurethane foam (SPF) insulation is used as thermal insulation for residential and commercial buildings. It has many advantages over other forms insulation; however, concerns have been raised related to chemical emissions during and after application. The American Chemistry Council's (ACC's) Center for the Polyurethanes Industry (CPI) has gathered previously unpublished industrial hygiene air sampling studies submitted by member companies that were completed during an eight-year period from 2007-2014. These studies address emissions from medium density closed cell and low density open cell formulations. This article summarizes the results of personal and area air samples collected during application and post application of SPF to interior building surfaces in both laboratory and field environments. Chemicals of interest included: Volatile Organic Compounds (VOCs), methylene diphenyl diisocyanate (MDI), flame retardants, amine catalysts, blowing agents, and aldehydes. Overall, the results indicate that SPF applicators and workers in close proximity to the application are potentially exposed to MDI in excess of recommended and governmental occupational exposure limits and should use personal protective equipment (PPE) consisting of air supplied respirators and full-body protective clothing to reduce exposure. Catalyst emissions can be reduced by using reactive catalysts in SPF formulations, and mechanical ventilation is important in controlling emissions during and after application.

  14. Preparation and characterization of new biologically active polyurethane foams.

    PubMed

    Savelyev, Yuri; Veselov, Vitali; Markovskaya, Ludmila; Savelyeva, Olga; Akhranovich, Elena; Galatenko, Natalya; Robota, Ludmila; Travinskaya, Tamara

    2014-12-01

    Biologically active polyurethane foams are the fast-developed alternative to many applications of biomedical materials. Due to the polyurethane structure features and foam technology it is possible to incorporate into their structure the biologically active compounds of target purpose via structural-chemical modification of macromolecule. A series of new biologically active polyurethane foams (PUFs) was synthesized with polyethers (MM 2500-5000), polyesters MM (500-2200), 2,4(2,6) toluene diisocyanate, water as a foaming agent, catalysts, foam stabilizers and functional compounds. Different functional compounds: 1,4-di-N-oxy-2,3-bis-(oxymethyl)-quinoxaline (DOMQ), partial sodium salt of poly(acrylic acid) and 2,6-dimethyl-N,N-diethyl aminoacetatanilide hydrochloride were incorporated into the polymer structure/composition due to the chemical and/or physical bonding. Structural peculiarities of PUFs were studied by FTIR spectroscopy and X-ray scattering. Self-adhesion properties of PUFs were estimated by measuring of tensile strength at break of adhesive junction. The optical microscopy method was performed for the PUF morphology studies. Toxicological estimation of the PUFs was carried out in vitro and in vivo. The antibacterial action towards the Gram-positive and Gram-negative bacteria (Escherichia coli ATC 25922, E. coli ATC 2150, Klebsiella pneumoniae 6447, Staphylococcus aureus 180, Pseudomonas aeruginosa 8180, Proteus mirabilis F 403, P. mirabilis 6054, and Proteus vulgaris 8718) was studied by the disc method on the solid nutrient. Physic-chemical properties of the PUFs (density, tensile strength and elongation at break, water absorption and vapor permeability) showed that all studied PUFs are within the operational requirements for such materials and represent fine-cellular foams. Spectral studies confirmed the incorporation of DOMQ into the PUF's macrochain. PUFs are characterized by microheterogeneous structure. They are antibacterially active, non-toxic materials with high affinity to the tissue body, self-adhesive properties and local anesthetic effect. Copyright © 2014 Elsevier B.V. All rights reserved.

  15. Bio-based rigid polyurethane foam from liquefied products of wood in the presence of polyhydric alcohols

    Treesearch

    Zhifeng Zheng; Hui Pan; Yuanbo Huang; Chung Y. Hse

    2011-01-01

    Rigid polyurethane foams were prepared from the liquefied wood polyols, which was obtained by the liquefaction of southern pine wood in the presence of polyhydric alcohols with sulfuric acid catalyst by using microwave-assistant as an energy source. The properties of liquefied biomass-based polyols and the rigid polyurethane foams were investigated. The results...

  16. Pullout strength of bone-patellar tendon-bone allograft bone plugs: a comparison of cadaver tibia and rigid polyurethane foam.

    PubMed

    Barber, F Alan

    2013-09-01

    To compare the load-to-failure pullout strength of bone-patellar tendon-bone (BPTB) allografts in human cadaver tibias and rigid polyurethane foam blocks. Twenty BPTB allografts were trimmed creating 25 mm × 10 mm × 10 mm tibial plugs. Ten-millimeter tunnels were drilled in 10 human cadaver tibias and 10 rigid polyurethane foam blocks. The BPTB anterior cruciate ligament allografts were inserted into these tunnels and secured with metal interference screws, with placement of 10 of each type in each material. After preloading (10 N), cyclic loading (500 cycles, 10 to 150 N at 200 mm/min) and load-to-failure testing (200 mm/min) were performed. The endpoints were ultimate failure load, cyclic loading elongation, and failure mode. No difference in ultimate failure load existed between grafts inserted into rigid polyurethane foam blocks (705 N) and those in cadaver tibias (669 N) (P = .69). The mean rigid polyurethane foam block elongation (0.211 mm) was less than that in tibial bone (0.470 mm) (P = .038), with a smaller standard deviation (0.07 mm for foam) than tibial bone (0.34 mm). All BPTB grafts successfully completed 500 cycles. The rigid polyurethane foam block showed less variation in test results than human cadaver tibias. Rigid polyurethane foam blocks provide an acceptable substitute for human cadaver bone tibia for biomechanical testing of BPTB allografts and offer near-equivalent results. Copyright © 2013 Arthroscopy Association of North America. Published by Elsevier Inc. All rights reserved.

  17. The Synergize effect of Chain extender to Phosporic acid catalyst to the ultimate property of Soy-Polyurethane

    NASA Astrophysics Data System (ADS)

    Elvistia Firdaus, Flora

    2016-04-01

    The polyurethanes (PUs) foam were made from vegetable oil; a soybean based polyol. The foams were categorized into flexible and semi rigid. This research is manufacturally designed polyurethane foams by a process requiring the reaction of mixture of 2, 4- and 2, 6-Toluene di Isocyanate isomers, soy polyol in the presence of other ingredients. The objective of this work was to functionalized soy-polyol using phosporic acid catalyst and chain extender, study their collaborative reaction in producing ultimate property of PU foam. Correlates the foam morphology images in accordance to mechanical properties of foams.

  18. Relative toxicity of pyrolysis products of some polyurethane and polychloroprene foams

    NASA Technical Reports Server (NTRS)

    Hilado, C. J.; Slattengren, C. L.; Kourtides, D. A.; Parker, J. A.

    1977-01-01

    Results of toxicity screening tests on some polyurethane and polychloroprene flexible foams are presented. The test method involves the exposure of four Swiss albino male mice in a 4.2-liter hemispherical chamber to the pyrolysis effluents from 1 g of sample exposed to temperatures rising from 200 to 800 C at a rate of 40 C/min. Mortality and times to incapacitation and to death are recorded. Comparisons indicate that flexible polyurethane foams without fire retardant are more toxic than the corresponding foams containing fire retardant, and polychloroprene foams are least toxic.

  19. 75 FR 18446 - Airworthiness Directives; The Boeing Company Model 747-100, 747-100B, 747-100B SUD, 747-200B, 747...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2010-04-12

    ... assemblies in the ECS with burned Boeing Material Specification (BMS) 8-39 polyurethane foam insulation. This... duct assemblies in the ECS wrapped with BMS 8-39 polyurethane foam insulation, a material of which the... electrical arc from igniting the BMS 8-39 polyurethane foam insulation on the duct assemblies of the ECS...

  20. Flexible and Lightweight Pressure Sensor Based on Carbon Nanotube/Thermoplastic Polyurethane-Aligned Conductive Foam with Superior Compressibility and Stability.

    PubMed

    Huang, Wenju; Dai, Kun; Zhai, Yue; Liu, Hu; Zhan, Pengfei; Gao, Jiachen; Zheng, Guoqiang; Liu, Chuntai; Shen, Changyu

    2017-12-06

    Flexible and lightweight carbon nanotube (CNT)/thermoplastic polyurethane (TPU) conductive foam with a novel aligned porous structure was fabricated. The density of the aligned porous material was as low as 0.123 g·cm -3 . Homogeneous dispersion of CNTs was achieved through the skeleton of the foam, and an ultralow percolation threshold of 0.0023 vol % was obtained. Compared with the disordered foam, mechanical properties of the aligned foam were enhanced and the piezoresistive stability of the flexible foam was improved significantly. The compression strength of the aligned TPU foam increases by 30.7% at the strain of 50%, and the stress of the aligned foam is 22 times that of the disordered foam at the strain of 90%. Importantly, the resistance variation of the aligned foam shows a fascinating linear characteristic under the applied strain until 77%, which would benefit the application of the foam as a desired pressure sensor. During multiple cyclic compression-release measurements, the aligned conductive CNT/TPU foam represents excellent reversibility and reproducibility in terms of resistance. This nice capability benefits from the aligned porous structure composed of ladderlike cells along the orientation direction. Simultaneously, the human motion detections, such as walk, jump, squat, etc. were demonstrated by using our flexible pressure sensor. Because of the lightweight, flexibility, high compressibility, excellent reversibility, and reproducibility of the conductive aligned foam, the present study is capable of providing new insights into the fabrication of a high-performance pressure sensor.

  1. [Cost-effectiveness of a TLC-NOSF polyurethane foam dressing].

    PubMed

    Arroyo Ana, Abejón; Alvarez Vázquez, Juan Carlos; Blasco García, Carmen; Bermejo Martínez, Mariano; López Casanova, Pablo; Cuesta Cuesta, Juan José; De Haro Fernández, Francisco; Mateo Marín, Emilia; Segovia Gómez, Teresa; Villar Rojas, Antonio Erasto

    2012-11-01

    Chronic wounds represent a drain on the Spanish health system, nowdays is necessary an optimization of the resources used and that is for this that is necessary justify the use of the products over others through cost-effective studies for to show the economic benefit to professionals and the life quality of patient. This article compares the use of a new technology for format polyurethane foam, TLC-NOSF, with the most commonly used products for treating wounds. This comparison is made using a cost-effectiveness model (Markov Model). The results demonstrate that treatment with polyurethane foam dressing with TLC-NOSF are cost-effective versus treatments with polyurethane foams most commonly used in Spain.

  2. Transient Thermal Response of Lightweight Cementitious Composites Made with Polyurethane Foam Waste

    NASA Astrophysics Data System (ADS)

    Kismi, M.; Poullain, P.; Mounanga, P.

    2012-07-01

    The development of low-cost lightweight aggregate (LWA) mortars and concretes presents many advantages, especially in terms of lightness and thermal insulation performances of structures. Low-cost LWA mainly comes from the recovery of vegetal or plastic wastes. This article focuses on the characterization of the thermal conductivity of innovative lightweight cementitious composites made with fine particles of rigid polyurethane (PU) foam waste. Five mortars were prepared with various mass substitution rates of cement with PU-foam particles. Their thermal conductivity was measured with two transient methods: the heating-film method and the hot-disk method. The incorporation of PU-foam particles causes a reduction of up to 18 % of the mortar density, accompanied by a significant improvement of the thermal insulating performance. The effect of segregation on the thermal properties of LWA mortars due to the differences of density among the cementitious matrix, sand, and LWA has also been quantified. The application of the hot-disk method reveals a gradient of thermal conductivity along the thickness of the specimens, which could be explained by a non-uniform repartition of fine PU-foam particles and mineral aggregates within the mortars. The results show a spatial variation of the thermal conductivity of the LWA mortars, ranging from 9 % to 19 %. However, this variation remains close to or even lower than that observed on a normal weight aggregate mortar. Finally, a self-consistent approach is proposed to estimate the thermal conductivity of PU-foam cement-based composites.

  3. Liquefaction of oak tree bark with different biomass/phenol mass ratios and utilizing bio-based polyols for carbon foam production

    NASA Astrophysics Data System (ADS)

    Ozbay, N.; Yargic, A. S.

    2017-02-01

    Carbon foam is sponge like carbonaceous material with low density, high conductivity and high strength; which is used in various applications such as catalyst supports, membrane separations, high thermally conductive heat sinks, energy absorption materials, high temperature thermal insulation. Coal or fossil oils are conventionally used to fabricate pitch, phenolic resin and polyurethane as carbon foam precursor. Biomass liquefaction is a developing technique to convert biomass resources into the industrial chemicals. In this study, oak tree bark was liquefied under mild conditions with different mass ratio of biomass/phenol; and the liquefaction product was used as polyol to produce porous resin foams. Obtained resin foams were carbonized at 400 °C, and then activated at 800 °C under nitrogen atmosphere. Structure evaluation of resin foams, carbonized foams and activated carbon foams from liquefied oak tree bark was investigated by using elemental analysis, x-ray diffraction, nitrogen adsorption/desorption isotherms, scanning electron microscopy, bulk density and compressive strength tests.

  4. Effect of flame retardants on the properties of monolithic and foamed polyurethanes at low temperatures

    NASA Astrophysics Data System (ADS)

    Yakushin, V. A.; Stirna, U. K.; Zhmud', N. P.

    1999-09-01

    The dependence of physical and mechanical properties of monolithic and foamed rigid polyurethanes on the content of flame retardants was investigated at 293 and 98 K. The character of the influence of the content of trichloroethyl phosphate on the ultimate tensile elongation and the coefficient of linear thermal expansion for monolithic and foamed polyurethanes at a temperature of 98 K was established.

  5. A semi-phenomenological model to predict the acoustic behavior of fully and partially reticulated polyurethane foams

    NASA Astrophysics Data System (ADS)

    Doutres, Olivier; Atalla, Noureddine; Dong, Kevin

    2013-02-01

    This paper proposes simple semi-phenomenological models to predict the sound absorption efficiency of highly porous polyurethane foams from microstructure characterization. In a previous paper [J. Appl. Phys. 110, 064901 (2011)], the authors presented a 3-parameter semi-phenomenological model linking the microstructure properties of fully and partially reticulated isotropic polyurethane foams (i.e., strut length l, strut thickness t, and reticulation rate Rw) to the macroscopic non-acoustic parameters involved in the classical Johnson-Champoux-Allard model (i.e., porosity ϕ, airflow resistivity σ, tortuosity α∝, viscous Λ, and thermal Λ' characteristic lengths). The model was based on existing scaling laws, validated for fully reticulated polyurethane foams, and improved using both geometrical and empirical approaches to account for the presence of membrane closing the pores. This 3-parameter model is applied to six polyurethane foams in this paper and is found highly sensitive to the microstructure characterization; particularly to strut's dimensions. A simplified micro-/macro model is then presented. It is based on the cell size Cs and reticulation rate Rw only, assuming that the geometric ratio between strut length l and strut thickness t is known. This simplified model, called the 2-parameter model, considerably simplifies the microstructure characterization procedure. A comparison of the two proposed semi-phenomenological models is presented using six polyurethane foams being either fully or partially reticulated, isotropic or anisotropic. It is shown that the 2-parameter model is less sensitive to measurement uncertainties compared to the original model and allows a better estimation of polyurethane foams sound absorption behavior.

  6. Probing nanodispersions of clays for reactive foaming.

    PubMed

    Harikrishnan, G; Lindsay, Chris I; Arunagirinathan, M A; Macosko, Christopher W

    2009-09-01

    Nanodispersions of clays in polyurethane components have been prepared. Nanoclays (both natural and organically modified) of various aspect ratios are used. The fillers are dispersed separately in polyurethane components, viz., polyol and polyisocyanate. The nanodispersions are characterized by the combined use of solution rheology, X-ray scattering, cryo-electron microscopy, and IR spectroscopy. Reactive foaming of these nanodispersions is carried out to make polyurethane nanocomposite foams. The status of the dispersion of fillers in components and in foams has been compared to investigate the effect of the foaming process in exfoliation. Interpretation of the results from different characterization techniques describes the state of the dispersion of fillers in components and in foam. The rheological and physicochemical behaviors of nanodispersions are shown to have a significant influence on the properties of nanocomposite foams.

  7. Experimental determination of drag coefficients in low-density polyurethane foam

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Adams, M L

    2006-04-18

    We describe several experiments performed at the LLNL Site 300 firing range and on the LLNL 1/3 scale gun to investigate the deceleration of small projectiles (l {approx} 3-5 [mm]) in low-density foam ({rho} {approx} 0.08-0.32 [g/cm{sup 3}]). The experiments at the firing range researched a passive velocity diagnostic based on Faraday's law of induction, while experiments on the 1/3 scale gun investigated the effects of varying projectile surface area, projectile shape, and foam density on the drag coefficient c{sub d}. Analysis shows that the velocity diagnostic has an uncertainty on the order of 1 percent for projectiles with velocitymore » v {approx} 0.8-1.2 [km/s]. The 1/3 scale gun experiments, dubbed the Krispy Kreme series, included nine shots considering the combinations of 3 projectile surface areas with 3 target densities. The experiments used Tantalum square surface area block projectiles (with an initial velocity v{sub 0} {approx} 1.2 [km/s], a common thickness T = 2.67 [mm], and square side lengths of 3, 4, and 5 [mm]) decelerating in polyurethane foams (with densities {rho}{sub f} of 0.08, 0.16 and 0.32 [g/cm{sup 3}]). Standard fluid models of the Krispy Kreme experiments predict Reynolds numbers Re {approx} 10{sup 5} - 10{sup 6}, Mach numbers Ma {approx} 0.5-2.0, and drag coefficients c{sub d} {approx} 2-3. However, the data indicate that c{sub d} = 1.1-1.2 (c{sub d} = 1.7) for all three block projectiles in the 0.08 and 0.16 [g/cm{sup 3}] targets (0.32 [g/cm{sup 3}] target). First, we conclude that the drag force on projectiles in solid polyurethane foam is less than in fluids with equivalent dimensionless parameters. This result is also supported by an additional Krispy Kreme experiment that used a disk projectile (with diameter d = 4.51 [mm] and thickness T = 2.67 [mm]) penetrating a target with density {rho} = 0.16 [g/cm{sup 3}], i.e., the fluid-like c{sub d} = 1.15 while the measured c{sub d} = 0.63. Second, we conclude that the measured drag coefficient in the lower density foam targets is less than in the larger density foam target. This result is corroborated by firing range experiments with M855 NATO bullets (with diameter 5.56 [mm], mass 4.1 [g], and initial velocity {nu}{sub 0} {approx} 800 [m/s]) fired from an M16 rifle, i.e., c{sub d} = 0.3 (c{sub d} = 0.6) in the 0.16 [g/cm{sup 3}] (0.32 [g/cm{sup 3}]) target. We propose future 1/3 scale gun experiments using a passive velocity diagnostic with increased spatial resolution as well as simple spherical projectiles with 0.5 and 1.0 [cm] diameters.« less

  8. Improving the Performance of Heat Insulation Polyurethane Foams by Silica Nanoparticles

    NASA Astrophysics Data System (ADS)

    Nikje, M. M. Alavi; Garmarudi, A. Bagheri; Haghshenas, M.; Mazaheri, Z.

    Heat insulation polyurethane foam materials were doped by silica nano particles, to investigate the probable improving effects. In order to achieve the best dispersion condition and compatibility of silica nanoparticles in the polymer matrix a modification step was performed by 3-aminopropyltriethoxysilane (APTS) as coupling agent. Then, thermal and mechanical properties of polyurethane rigid foam were investigated. Thermal and mechanical properties were studied by tensile machine, thermogravimetric analysis and dynamic mechanical analysis.

  9. Formulation, Preparation, and Characterization of Polyurethane Foams

    ERIC Educational Resources Information Center

    Pinto, Moises L.

    2010-01-01

    Preparation of laboratory-scale polyurethane foams is described with formulations that are easy to implement in experiments for undergraduate students. Particular attention is given to formulation aspects that are based on the main chemical reactions occurring in polyurethane production. This allows students to develop alternative formulations to…

  10. Influence of carbon nanotubes on mechanical properties and structure of rigid polyurethane foam

    NASA Astrophysics Data System (ADS)

    Ciecierska, E.; Jurczyk-Kowalska, M.; Bazarnik, P.; Kulesza, M.; Lewandowska, M.; Kowalski, M.; Krauze, S.

    2014-08-01

    In this work, the influence of carbon nanotubes addition on foam structure and mechanical properties of rigid polyurethane foam/nanotube composites was investigated. Scanning electron microscopy was performed to reveal the foam porous structure and distribution of carbon nanotubes. To determine the mechanical properties, three point bending tests were carried out.

  11. Fabrication of a superhydrophobic polyurethane foam and its application for continuous oil removal

    NASA Astrophysics Data System (ADS)

    Liu, Hai-Dong; Gu, Bin; Yuan, Wei-Feng; He, Qi

    2018-02-01

    A new polyurethane foam with superhydrophobicity and excellent lipophilicity is presented and demonstrated experimentally in this work. The superhydrophobic foam is synthesized by dip coating the polyurethane foam with a mixture solution of silicone resine and silicon dioxide nanoparticles. Its superhydrophobic and oleophilic capacity is characterized and verified via the SEM images, the water contact angle measurement, the adsorption tests and recyclability tests for water and some typical oils. Combining with the vacuum assisted oil-water separation technology (VAST), continuous recovery of oil spill at the lab scale is realized on the new superhydrophobic foam. Moreover, the break through pressure for water penetrating through the superhydrophobic foam is determined experimentally and referred as the maximum operation pressure in the VAST.

  12. Determination of tissue equivalent materials of a physical 8-year-old phantom for use in computed tomography

    NASA Astrophysics Data System (ADS)

    Akhlaghi, Parisa; Miri Hakimabad, Hashem; Rafat Motavalli, Laleh

    2015-07-01

    This paper reports on the methodology applied to select suitable tissue equivalent materials of an 8-year phantom for use in computed tomography (CT) examinations. To find the appropriate tissue substitutes, first physical properties (physical density, electronic density, effective atomic number, mass attenuation coefficient and CT number) of different materials were studied. Results showed that, the physical properties of water and polyurethane (as soft tissue), B-100 and polyvinyl chloride (PVC) (as bone) and polyurethane foam (as lung) agree more with those of original tissues. Then in the next step, the absorbed doses in the location of 25 thermoluminescent dosimeters (TLDs) as well as dose distribution in one slice of phantom were calculated for original and these proposed materials by Monte Carlo simulation at different tube voltages. The comparisons suggested that at tube voltages of 80 and 100 kVp using B-100 as bone, water as soft tissue and polyurethane foam as lung is suitable for dosimetric study in pediatric CT examinations. In addition, it was concluded that by considering just the mass attenuation coefficient of different materials, the appropriate tissue equivalent substitutes in each desired X-ray energy range could be found.

  13. Water-free synthesis of polyurethane foams using highly reactive diisocyanates derived from 5-hydroxymethylfurfural.

    PubMed

    Neumann, Christopher N D; Bulach, Winfried D; Rehahn, Matthias; Klein, Roland

    2011-09-01

    This paper reports on the synthesis of a new highly reactive diisocyanate monomer based on hydroxymethylfurfural. It further describes its catalyst-free conversion to linear-chain thermoplastic polyurethanes as well as to cross-linked polyurethane foams. In addition, a novel strategy for the synthesis of polyurethane foams without the necessity of using water is developed. Nitrogen is utilized herein as blowing agent which is formed during Curtius rearrangement of a new furan based carboxylic azide into its corresponding diisocyanate. Copyright © 2011 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  14. The effect of moisture absorption on the physical properties of polyurethane shape memory polymer foams.

    PubMed

    Yu, Ya-Jen; Hearon, Keith; Wilson, Thomas S; Maitland, Duncan J

    2011-08-01

    The effect of moisture absorption on the glass transition temperature (T(g)) and stress/strain behavior of network polyurethane shape memory polymer (SMP) foams has been investigated. With our ultimate goal of engineering polyurethane SMP foams for use in blood contacting environments, we have investigated the effects of moisture exposure on the physical properties of polyurethane foams. To our best knowledge, this study is the first to investigate the effects of moisture absorption at varying humidity levels (non-immersion and immersion) on the physical properties of polyurethane SMP foams. The SMP foams were exposed to differing humidity levels for varying lengths of time, and they exhibited a maximum water uptake of 8.0% (by mass) after exposure to 100% relative humidity for 96 h. Differential scanning calorimetry results demonstrated that water absorption significantly decreased the T(g) of the foam, with a maximum water uptake shifting the T(g) from 67 °C to 5 °C. Samples that were immersed in water for 96 h and immediately subjected to tensile testing exhibited 100% increases in failure strains and 500% decreases in failure stresses; however, in all cases of time and humidity exposure, the plasticization effect was reversible upon placing moisture-saturated samples in 40% humidity environments for 24 h.

  15. The effect of moisture absorption on the physical properties of polyurethane shape memory polymer foams

    PubMed Central

    Yu, Ya-Jen; Hearon, Keith; Wilson, Thomas S.; Maitland, Duncan J.

    2011-01-01

    The effect of moisture absorption on the glass transition temperature (Tg) and stress/strain behavior of network polyurethane shape memory polymer (SMP) foams has been investigated. With our ultimate goal of engineering polyurethane SMP foams for use in blood contacting environments, we have investigated the effects of moisture exposure on the physical properties of polyurethane foams. To our best knowledge, this study is the first to investigate the effects of moisture absorption at varying humidity levels (non-immersion and immersion) on the physical properties of polyurethane SMP foams. The SMP foams were exposed to differing humidity levels for varying lengths of time, and they exhibited a maximum water uptake of 8.0% (by mass) after exposure to 100% relative humidity for 96 h. Differential scanning calorimetry results demonstrated that water absorption significantly decreased the Tg of the foam, with a maximum water uptake shifting the Tg from 67 °C to 5 °C. Samples that were immersed in water for 96 h and immediately subjected to tensile testing exhibited 100% increases in failure strains and 500% decreases in failure stresses; however, in all cases of time and humidity exposure, the plasticization effect was reversible upon placing moisture-saturated samples in 40% humidity environments for 24 h. PMID:21949469

  16. The effect of moisture absorption on the physical properties of polyurethane shape memory polymer foams

    NASA Astrophysics Data System (ADS)

    Yu, Ya-Jen; Hearon, Keith; Wilson, Thomas S.; Maitland, Duncan J.

    2011-08-01

    The effect of moisture absorption on the glass transition temperature (Tg) and the stress/strain behavior of network polyurethane shape memory polymer (SMP) foams has been investigated. With our ultimate goal of engineering polyurethane SMP foams for use in blood-contacting environments, we have investigated the effects of moisture exposure on the physical properties of polyurethane foams. To the best of our knowledge, this study is the first to investigate the effects of moisture absorption at varying humidity levels (non-immersion and immersion) on the physical properties of polyurethane SMP foams. The SMP foams were exposed to differing humidity levels for varying lengths of time, and they exhibited a maximum water uptake of 8.0% (by mass) after exposure to 100% relative humidity for 96 h. Differential scanning calorimetry results demonstrated that water absorption significantly decreased the Tg of the foam, with a maximum water uptake shifting the Tg from 67 to 5 °C. Samples that were immersed in water for 96 h and immediately subjected to tensile testing exhibited 100% increases in failure strains and 500% decreases in failure stresses; however, in all cases of time and humidity exposure, the plasticization effect was reversible upon placing moisture-saturated samples in 40% humidity environments for 24 h.

  17. Storage-stable foamable polyurethane is activated by heat

    NASA Technical Reports Server (NTRS)

    1966-01-01

    Polyurethane foamable mixture remains inert in storage unit activated to produce a rapid foaming reaction. The storage-stable foamable composition is spread as a paste on the surface of an expandable structure and, when heated, yields a rigid open-cell polyurethane foam that is self-bondable to the substrate.

  18. The effect of changes in the USF/NASA toxicity screening test method on data from some cellular polymers

    NASA Technical Reports Server (NTRS)

    Hilado, C. J.; Miller, C. M.

    1976-01-01

    Rankings of relative toxicity can be markedly affected by changes in test variables. Revision of the USF/NASA toxicity screening test procedure to eliminate the connecting tube and supporting floor and incorporate a 1.0 g sample weight, 200 C starting temperature, and 800 C upper limit temperature for pyrolysis, reversed the rankings of flexible polyurethane and polychloroprene foams, not only in relation to each other, but also in relation to cotton and red oak. Much of the change is attributed to reduction of the distance between the sample and the test animals, and reduction of the sample weight charged. Elimination of the connecting tube increased the relative toxicity of the polyurethane foams. The materials tested were flexible polyurethane foam, without and with fire retardant; rigid polyurethane foam with fire retardant; flexible polychloroprene foam; cotton, Douglas fir, red oak, hemlock, hardboard, particle board, polystyrene, and polymethyl methacrylate.

  19. Treatment of concentrated industrial wastewaters originating from oil shale and the like by electrolysis polyurethane foam interaction

    DOEpatents

    Tiernan, Joan E.

    1990-01-01

    Highly concentrated and toxic petroleum-based and synthetic fuels wastewaters such as oil shale retort water are treated in a unit treatment process by electrolysis in a reactor containing oleophilic, ionized, open-celled polyurethane foams and subjected to mixing and laminar flow conditions at an average detention time of six hours. Both the polyurethane foams and the foam regenerate solution are re-used. The treatment is a cost-effective process for waste-waters which are not treatable, or are not cost-effectively treatable, by conventional process series.

  20. 40 CFR 63.8780 - What is the purpose of this subpart?

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... (CONTINUED) National Emission Standards for Hazardous Air Pollutants: Flexible Polyurethane Foam Fabrication... national emission standards for hazardous air pollutants (NESHAP) emitted from flexible polyurethane foam...

  1. 40 CFR 63.8780 - What is the purpose of this subpart?

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... (CONTINUED) National Emission Standards for Hazardous Air Pollutants: Flexible Polyurethane Foam Fabrication... national emission standards for hazardous air pollutants (NESHAP) emitted from flexible polyurethane foam...

  2. 40 CFR 63.8780 - What is the purpose of this subpart?

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... (CONTINUED) National Emission Standards for Hazardous Air Pollutants: Flexible Polyurethane Foam Fabrication... national emission standards for hazardous air pollutants (NESHAP) emitted from flexible polyurethane foam...

  3. 40 CFR 63.8780 - What is the purpose of this subpart?

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ...) National Emission Standards for Hazardous Air Pollutants: Flexible Polyurethane Foam Fabrication Operations... national emission standards for hazardous air pollutants (NESHAP) emitted from flexible polyurethane foam...

  4. 40 CFR 63.8780 - What is the purpose of this subpart?

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... (CONTINUED) National Emission Standards for Hazardous Air Pollutants: Flexible Polyurethane Foam Fabrication... national emission standards for hazardous air pollutants (NESHAP) emitted from flexible polyurethane foam...

  5. 40 CFR 63.1307 - Recordkeeping requirements.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... Standards for Hazardous Air Pollutants for Flexible Polyurethane Foam Production § 63.1307 Recordkeeping... paragraphs (c)(1)(i), (ii), (iii), and (iv) of this section. Each flexible polyurethane foam slabstock source...) through (C) of this section. (A) A log of foam runs each day. For each run, the log shall include a list...

  6. 40 CFR 63.1307 - Recordkeeping requirements.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... Standards for Hazardous Air Pollutants for Flexible Polyurethane Foam Production § 63.1307 Recordkeeping... paragraphs (c)(1)(i), (ii), (iii), and (iv) of this section. Each flexible polyurethane foam slabstock source...) through (C) of this section. (A) A log of foam runs each day. For each run, the log shall include a list...

  7. 40 CFR 63.1307 - Recordkeeping requirements.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... Standards for Hazardous Air Pollutants for Flexible Polyurethane Foam Production § 63.1307 Recordkeeping... paragraphs (c)(1)(i), (ii), (iii), and (iv) of this section. Each flexible polyurethane foam slabstock source...) through (C) of this section. (A) A log of foam runs each day. For each run, the log shall include a list...

  8. Flame Retardants Used in Flexible Polyurethane Foam

    EPA Pesticide Factsheets

    The partnership project on flame retardants in furniture seeks to update the health and environmental profiles of flame-retardant chemicals that meet fire safety standards for upholstered consumer products with polyurethane foam

  9. Microcellular injection molding process for producing lightweight thermoplastic polyurethane with customizable properties

    NASA Astrophysics Data System (ADS)

    Ellingham, Thomas; Kharbas, Hrishikesh; Manitiu, Mihai; Scholz, Guenter; Turng, Lih-Sheng

    2018-03-01

    A three-stage molding process involving microcellular injection molding with core retraction and an "out-of-mold" expansion was developed to manufacture thermoplastic polyurethane into lightweight foams of varying local densities, microstructures, and mechanical properties in the same microcellular injection molded part. Two stages of cavity expansion through sequential core retractions and a third expansion in a separate mold at an elevated temperature were carried out. The densities varied from 0.25 to 0.42 g/cm3 (77% to 62% weight reduction). The mechanical properties varied as well. Cyclic compressive strengths and hysteresis loss ratios, together with the microstructures, were characterized and reported.

  10. Effect of the chemical structure of the polymer matrix on the properties of foam polyurethanes at low temperatures

    NASA Astrophysics Data System (ADS)

    Yakushin, V. A.; Stirna, U. K.; Zhmud', N. P.

    1999-07-01

    The dependence of physical and mechanical properties of oligoether-based foam polyurethanes on the molecular mass (Mc) of polymer chains between the nodes of the polymer network and on the content of rigid segments in the polymer is investigated at 293 and 98K. The values of Mc at which the foam plastics have the best mechanical properties at low temperatures are determined. The content of rigid segments in the polymer at which foam polyurethanes have the best combination of the linear thermal expansion coefficient and mechanical properties in tension at a temperature of 98K is found.

  11. Catalytic thermal cracking of post-consumer waste plastics to fuels: Part 1 - Kinetics and optimization

    USDA-ARS?s Scientific Manuscript database

    Thermogravimetric analysis (TGA) was used to investigate thermal and catalytic pyrolysis of waste plastics such as prescription bottles (polypropylene/PP), high density polyethylene, landfill liners (polyethylene/PE), packing materials (polystyrene/PS), and foams (polyurethane/PU) into crude plastic...

  12. Lightweight bio-composites based on hemp fibres produced by conventional and unconventional processes

    NASA Astrophysics Data System (ADS)

    Boccarusso, L.; Durante, M.; Formisano, A.; Langella, A.; Minutolo, F. Memola Capece

    2017-10-01

    Considering that nowadays the interest in the use of bio-composite materials is increasing more and more, this work is focused on the manufacturing of lightweight components based on hemp fibres for future applications, for example as a core for sandwich structures. Three different no-complex processes were used: a conventional hand lay-up, an unconventional infusion process and a hand lay-up process followed by injection moulding. They were used to produce bio-composite structures using an epoxy resin and/or a polyurethane foam as matrix. Depending on the process used for the manufacturing, laminates with different values of density were obtained. A detailed study in terms of both static and dynamic properties was carried out and the different mechanical behaviour for each sample typology was highlighted. The results showed that the process in which both the epoxy resin and the polyurethane foam were used as matrix allowed to obtain laminates with lower density and higher specific mechanical properties.

  13. Electrical conductivity of rigid polyurethane foam at high temperature

    NASA Astrophysics Data System (ADS)

    Johnson, R. T., Jr.

    1982-08-01

    The electrical conductivity of rigid polyurethane foam, used for electronic encapsulation, was measured during thermal decomposition to 3400 C. At higher temperatures the conductance continues to increase. With pressure loaded electrical leads, sample softening results in eventual contact between electrodes which produces electrical shorting. Air and nitrogen environments show no significant dependence of the conductivity on the atmosphere over the temperature range. The insulating characteristics of polyurethane foam below approx. 2700 C are similar to those for silicone based materials used for electronic case housings and are better than those for phenolics. At higher temperatures (greater than or equal to 2700 C) the phenolics appear to be better insulators to approx. 5000 C and the silicones to approx. 6000 C. It is concluded that the Sylgard 184/GMB encapsulant is a significantly better insulator at high temperature than the rigid polyurethane foam.

  14. Aluminum phosphate microcapsule flame retardants for flexible polyurethane foams

    NASA Astrophysics Data System (ADS)

    Zhang, Bin; Liu, Hong; Han, Jian

    2018-04-01

    In this study, highly efficient flame-retardant aluminum phosphate (ALP) microcapsules were synthesized from ALP and ammonium phosphomolybdate trihydrate. The chemical structure of the ALP microcapsules was characterized by scanning electron microscopy and elemental analysis, and the thermal degradation behavior was investigated by thermogravimetric analysis (TGA). Subsequently, flexible polyurethane (PU) foams were prepared with the ALP microcapsules. Limiting oxygen index (LOI) tests, vertical burning tests, smoke density rating (SDR), and cone calorimetric tests were employed to investigate the combustion of the materials. The results showed that the flexible PU foams with 15 parts per hundred polyol by weight (pphp) ALP microcapsules passed the vertical burning test and they had an increased LOI value of 28.5%. The SDR value for PU/20 pphp ALP microcapsule composites was about 16.0% and the SDR value for the pure PU was about 29.0%. The corresponding flame-retardant mechanism was investigated by Fourier transform infrared spectroscopy, TGA, Pyrolysis Gas Chromatography Mass Spectrometry (Py-GC/MS) tests, and energy-dispersive X-ray spectrometry.

  15. Synthesis of Transesterified Palm Olein-Based Polyol and Rigid Polyurethanes from this Polyol.

    PubMed

    Arniza, Mohd Zan; Hoong, Seng Soi; Idris, Zainab; Yeong, Shoot Kian; Hassan, Hazimah Abu; Din, Ahmad Kushairi; Choo, Yuen May

    Transesterification of palm olein with glycerol can increase the functionality by introducing additional hydroxyl groups to the triglyceride structure, an advantage compared to using palm olein directly as feedstock for producing palm-based polyol. The objective of this study was to synthesize transesterified palm olein-based polyol via a three-step reaction: (1) transesterification of palm olein, (2) epoxidation and (3) epoxide ring opening. Transesterification of palm olein yielded approximately 78 % monoglyceride and has an hydroxyl value of approximately 164 mg KOH g -1 . The effect of formic acid and hydrogen peroxide concentrations on the epoxidation reaction was studied. The relationships between epoxide ring-opening reaction time and residual oxirane oxygen content and hydroxyl value were monitored. The synthesized transesterified palm olein-based polyol has hydroxyl value between 300 and 330 mg KOH g -1 and average molecular weight between 1,000 and 1,100 Da. On the basis of the hydroxyl value and average molecular weight of the polyol, the transesterified palm olein-based polyol is suitable for producing rigid polyurethane foam, which can be designed to exhibit desirable properties. Rigid polyurethane foams were synthesized by substituting a portion of petroleum-based polyol with the transesterified palm olein-based polyol. It was observed that by increasing the amount of transesterified palm olein-based polyol, the core density and compressive strength were reduced but at the same time the insulation properties of the rigid polyurethane foam were improved.

  16. Properties of Polymer-Infiltrated Carbon Foams

    NASA Astrophysics Data System (ADS)

    Adams, W. A.; Bunning, T. J.; Farmer, B. L.; Kearns, K. M.; Anderson, D. A.; Roy, A. K.; Banerjee, T.; Jeon, H. G.

    2001-03-01

    There is considerable interest in extending the use-temperatures of both commodity and high performance polymers. There is also interest in improving the mechanical strength of carbon foams. Composites prepared by infiltrating carbon foam with polymers may offer significant improvements in both, the polymer helping to rigidize the foam and the foam providing thermal protection by virtue of its high thermal conductivity. The mechanical properties and thermal stability of carbon foams of various densities infiltrated with polyurethane have been studied. When used with a heat sink, the composite is able to maintain a substantial thermal gradient which provides stability of the polymer nominally above its decomposition temperature. The composite also has much improved strength properties without sacrificing tensile modulus. The composites may be very well suited for thermal management applications.

  17. Comparison of clinical outcomes of three different packing materials in the treatment of severe acute otitis externa.

    PubMed

    Demir, D; Yılmaz, M S; Güven, M; Kara, A; Elden, H; Erkorkmaz, Ü

    2018-06-13

    To analyse the clinical outcomes of biodegradable synthetic polyurethane foam versus ribbon gauze and ear wick in the treatment of severe acute otitis externa. Ninety-two adults with severe acute otitis externa were randomly assigned to groups receiving ear wick (n = 28), ribbon gauze (n = 34) or biodegradable synthetic polyurethane foam (n = 30). Clinical efficacy, in terms of otalgia, oedema, erythema and tenderness of the external auditory canal, was assessed before packing was applied and at follow up on the 3rd and 7th days of presentation. All packing materials were associated with improved otalgia and oedema on the 3rd day; however, there were significant differences between biodegradable synthetic polyurethane foam and the other packing materials, and there was no significant reduction in tenderness in the biodegradable synthetic polyurethane foam group on the 3rd day. In the ribbon gauze and ear wick groups, improvements in all clinical efficacy scores were statistically significant for all pairwise comparisons. The three packing materials were all quite effective in treating severe acute otitis externa, but ear wick and ribbon gauze were superior to biodegradable synthetic polyurethane foam for relieving signs and symptoms, especially on the 3rd day.

  18. Characterization of biobased polyurethane foams employing lignin fractionated from microwave liquefied switchgrass

    Treesearch

    Xingyan Huang; Cornelis F. De Hoop; Jiulong Xie; Chung-Yun Hse; Jinqiu Qi; Tingxing Hu

    2017-01-01

    Lignin samples fractionated from microwave liquefied switchgrass were applied in the preparation of semirigid polyurethane (PU) foams without purification.The objective of this study was to elucidate the influence of lignin in the PU matrix on themorphological, chemical, mechanical, and thermal properties of thePU foams.The scanning electron microscopy (SEM) images...

  19. 40 CFR Appendix M to Subpart G of... - Unacceptable Substitutes Listed in the September 30, 2004 Final Rule, Effective November 29, 2004

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... refrigeration, and sandwich panels —Rigid polyurethane slabstock and other foams —Polystyrene extruded... 29, 2004 Foam Blowing—Unacceptable Substitutes End-use Substitute Decision Comments All foam end-uses: HCFC-141b Unacceptable Alternatives exist with lower or zero = ODP. —Rigid polyurethane and...

  20. Effect of foam age on toxicity of pyrolysis gases from polyurethane flexible foams

    NASA Technical Reports Server (NTRS)

    Hilado, C. J.; Murphy, R. M.

    1978-01-01

    The toxicity of the pyrolysis gases from some samples of polyurethane flexible foams appears to have decreased with age, while other samples seem to exhibit no significant change with age in this respect. The changes observed were greater than could be accounted for by variations in the material, or test variations or artifacts.

  1. 40 CFR Appendix M to Subpart G of... - Unacceptable Substitutes Listed in the September 30, 2004 Final Rule, Effective November 29, 2004

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... refrigeration, and sandwich panels —Rigid polyurethane slabstock and other foams —Polystyrene extruded... 29, 2004 Foam Blowing—Unacceptable Substitutes End-use Substitute Decision Comments All foam end-uses: HCFC-141b Unacceptable Alternatives exist with lower or zero = ODP. —Rigid polyurethane and...

  2. Study on Thermal Conductivities of Aromatic Polyimide Aerogels.

    PubMed

    Feng, Junzong; Wang, Xin; Jiang, Yonggang; Du, Dongxuan; Feng, Jian

    2016-05-25

    Polyimide aerogels for low density thermal insulation materials were produced by 4,4'-diaminodiphenyl ether and 3,3',4,4'-biphenyltetracarboxylic dianhydride, cross-linked with 1,3,5-triaminophenoxybenzene. The densities of obtained polyimide aerogels are between 0.081 and 0.141 g cm(-3), and the specific surface areas are between 288 and 322 m(2) g(-1). The thermal conductivities were measured by a Hot Disk thermal constant analyzer. The value of the measured thermal conductivity under carbon dioxide atmosphere is lower than that under nitrogen atmosphere. Under pressure of 5 Pa at -130 °C, the thermal conductivity is the lowest, which is 8.42 mW (m K)(-1). The polyimide aerogels have lower conductivity [30.80 mW (m K)(-1)], compared to the value for other organic foams (polyurethane foam, phenolic foam, and polystyrene foam) with similar apparent densities under ambient pressure at 25 °C. The results indicate that polyimide aerogel is an ideal insulation material for aerospace and other applications.

  3. Tests of two new polyurethane foam wheelchair tires.

    PubMed

    Gordon, J; Kauzlarich, J J; Thacker, J G

    1989-01-01

    The performance characteristics of four 24-inch wheelchair tires are considered; one pneumatic and three airless. Specifically, two new airless polyurethane foam tires (circular and tapered cross-section) were compared to both a molded polyisoprene tire and a rubber pneumatic tire. Rolling resistance, coefficient of static friction, spring rate, tire roll-off, impact absorption, wear resistance, and resistance to compression set were the characteristics considered for the basis of comparison. Although the pneumatic tire is preferred by many wheelchair users, the two new polyurethane foam tires were found to offer a performance similar to the high-pressure pneumatic tire. In addition, the foam tires are less expensive and lighter in weight than the other tires tested.

  4. Morphologies, Processing and Properties of Ceramic Foams from Pre-Ceramic Foams from Pre-Ceramic Polymer Routes

    NASA Technical Reports Server (NTRS)

    Stackpoole, Mairead; Simoes, Conan R.; Venkatapathy, Ethiras (Technical Monitor)

    2002-01-01

    The current research is focused on processing ceramic foams that have potential as a thermal protection material. Ceramic foams with different architectures were formed from the pyrolysis of pre-ceramic polymers at 1200 C in different atmospheres. In some systems a sacrificial polyurethane was used as the blowing agent. We have also processed foams using sacrificial fillers to introduce controlled cell sizes. Each sacrificial filler or blowing agent leads to a unique morphology. The effect of different fillers on foam morphologies will be presented. The presentation will also focus on characterization of these foams in terms of mechanical and thermal properties. Foams processed using these approaches having bulk densities ranging from 0.15 to 0.9 g per cubic centimeter and a cell sizes from 5 to 500 micrometers. Compression strengths ranged from 2 to 7 MPa for these materials.

  5. The axial crushes behaviour on foam-filled round Jute/Polyester composite tubes

    NASA Astrophysics Data System (ADS)

    Othman, A.; Ismail, A. E.

    2018-04-01

    The present paper investigates the effect of axial loading compression on jute fibre reinforced polyester composite round tubes. The specimen of composite tube was fabricated by hand lay-up method of 120 mm length with fix 50.8 mm inner diameter to determine the behaviour of energy absorption on number of layers of 450 angle fibre and internally reinforced with and without foam filler material. The foam filler material used in this studies were polyurethane (PU) and polystyrene (PE) with average of 40 and 45 kg/m3 densities on the axial crushing load against displacement relations and on the failure modes. The number of layers of on this study were two; three and four were selected to calculate the crush force efficiency (CFE) and the specific energy absorption (SEA) of the composite tubes. Result indicated that the four layers’ jute/polyester show significant value in term of crushing load compared to 2 and 3 layers higher 60% for 2 layer and 3% compared to 3 layers. It has been found that the specific energy absorption of the jute/polyester tubes with polystyrene foam-filled is found higher respectively 10% to 12% than empty and polyurethane (PU) foam tubes. The increase in the number of layers from two to four increases the mean axial load from 1.01 KN to 3.60 KN for empty jute/polyester and from 2.11 KN to 4.26 KN for the polyurethane (PU) foam-filled jute/polyester tubes as well as for 3.60 KN to 5.58 KN for the polystyrene (PE) foam-filled jute/polyester. The author’s found that the failure of mechanism influence the characteristic of curve load against displacement obtained and conclude that an increasing number of layers and introduce filler material enhance the capability of specific absorbed energy.

  6. Polyurethane foam for roadway stabilization NH Route 129, Loudon, NH.

    DOT National Transportation Integrated Search

    2016-12-12

    This report summarizes the evaluation of the performance of polyurethane foam as a method of roadway : stabilization for a rural roadway experiencing substantial frost heaving. : NHDOT is responsible for many roads which have evolved from gravel road...

  7. Polyurethane foam for roadway stabilization NH route 129, Loudon, NH.

    DOT National Transportation Integrated Search

    2016-12-12

    This report summarizes the evaluation of the performance of polyurethane foam as a method of roadway : stabilization for a rural roadway experiencing substantial frost heaving. : NHDOT is responsible for many roads which have evolved from gravel road...

  8. Rigid open-cell polyurethane foam for cryogenic insulation

    NASA Technical Reports Server (NTRS)

    Faddoul, J. R.; Lindquist, C. R.; Niendorf, L. R.; Nies, G. E.; Perkins, P. J., Jr.

    1971-01-01

    Lightweight polyurethane foam assembled in panels is effective spacer material for construction of self-evacuating multilayer insulation panels for cryogenic liquid tanks. Spacer material separates radiation shields with barrier that minimizes conductive and convective heat transfer between shields.

  9. Development of high-performance biodegradable rigid polyurethane foams using all bioresource-based polyols: Lignin and soy oil-derived polyols.

    PubMed

    Luo, Xiaogang; Xiao, Yuqin; Wu, Qiangxian; Zeng, Jian

    2018-04-25

    Development of biodegradable polyurethane materials is the most promising in the wider context of the "greening" of industrial chemistry. To tackle this challenge, a novel biodegradable polyurethane foam from all bioresource-based polyols (lignin and soy oil-derived polyols) and polymeric methyldiphenyl diisocyanate (pMDI) have been synthesized via a one-pot and self-rising process. All these foam samples have the internal cellular morphology and microstructure. FTIR result exhibits characteristic peaks of polyurethane, and indicates covalent bonds between soy-based polyurethane and lignin, and the lignin powders can react with pMDI via active -H and -CNO. In addition, hydrogen bonding also plays an important role in forming the 3D structures. These interactions and chemical bonds made the prepared foam samples form the 3D macromolecular structure with improved mechanical, thermal, and biodegradable properties. The reaction process is time-saving and cost-effective as it requires no blowing agent and minimum processing steps, while exploring the potential of using the higher content of nature bioresource constituents. Copyright © 2018 Elsevier B.V. All rights reserved.

  10. Rigid zeolite containing polyurethane foams

    DOEpatents

    Frost, Charles B.

    1985-01-01

    A closed cell rigid polyurethane foam has been prepared which contains up to about 60% by weight of molecular sieves capable of sorbing molecules with effective critical diameters of up to about 10 .ANG.. The molecular sieve component of the foam can be preloaded with catalysts or with reactive compounds that can be released upon activation of the foam to control and complete crosslinking after the foam is formed. The foam can also be loaded with water or other flame-retarding agents, after completion. Up to about 50% of the weight of the isocyanate component of the foam can be replaced by polyimide resin precursors for incorporation into the final polymeric network.

  11. Rigid zeolite containing polyurethane foams

    DOEpatents

    Frost, C.B.

    1984-05-18

    A closed cell rigid polyurethane foam has been prepared which contains up to about 60% by weight of molecular sieves capable of sorbing molecules with effective critical diameters of up to about 10 A. The molecular sieve component of the foam can be preloaded with catalysts or with reactive compounds that can be released upon activation of the foam to control and complete crosslinking after the foam is formed. The foam can also be loaded with water or other flame-retarding agents, after completion. Up to about 50% of the weight of the isocyanate component of the foam can be replaced by polyimide resin precursors for incorporation into the final polymeric network.

  12. Measuring Rind Thickness on Polyurethane Foam

    NASA Technical Reports Server (NTRS)

    Johnson, C.; Miller, J.; Brown, H.

    1985-01-01

    Nondestructive test determines rind thickness of polyurethane foam. Surface harness of foam measured by Shore durometer method: hardness on Shore D scale correlates well with rind thickness. Shore D hardness of 20, for example, indicates rind thickness of 0.04 inch (1 millimeter). New hardness test makes it easy to determine rind thickness of sample nondestructively and to adjust fabrication variables accordingly.

  13. Characterization of compressive and short beam shear strength of bamboo opened cell foam core sandwich composites

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Setyawan, Paryanto Dwi, E-mail: paryanto-ds@yahoo.com; Sugiman,; Saputra, Yudhi

    The paper presents the compressive and the short beam shear strength of a sandwich composite with opened cell foam made of bamboo fiber as the core and plywood as the skins. The core thickness was varied from 10 mm to 40 mm keeping the volume fraction of fiber constant. Several test s were carried out including the core density, flatwise compressive and the short beam shear testing in three point bending. The results show that the density of bamboo opened cell foam is comparable with commercial plastic foam, such as polyurethane foam. The compressive strength tends to increase linearly with increasing themore » core thickness. The short beam shear failure load of the sandwich composite increases with the increase of core thickness, however on the contrary, the short beam shear strength which tends to sharply decrease from the thickness of 10 mm to 30 mm and then becomes flat.« less

  14. 3D simulation of polyurethane foam injection and reacting mold flow in a complex geometry

    NASA Astrophysics Data System (ADS)

    Özdemir, İ. Bedii; Akar, Fırat

    2018-05-01

    The aim of the present work is to develop a flow model which can be used to determine the paths of the polyurethane foam in the mold filling process of a refrigerator cabinet so that improvements in the distribution and the size of the venting holes can be achieved without the expensive prototyping and experiments. For this purpose, the multi-component, two-phase chemically reacting flow is described by Navier Stokes and 12 scalar transport equations. The air and the multi-component foam zones are separated by an interface, which moves only with advection since the mass diffusion of species are set zero in the air zone. The inverse density, viscosity and other diffusion coefficients are calculated by a mass fraction weighted average of the corresponding temperature-dependent values of all species. Simulations are performed in a real refrigerator geometry, are able to reveal the problematical zones where air bubbles and voids trapped in the solidified foam are expected to occur. Furthermore, the approach proves itself as a reliable design tool to use in deciding the locations of air vents and sizing the channel dimensions.

  15. The management of amputations of the leg using a new rigid foam plaster for prosthetic fitting.

    PubMed

    Hölter, W; Echterhoff, M; Blömer, A; Verfürden, H

    1980-01-01

    This paper describes the use of a rigid polyurethane foam to construct a stump socket for immediate or early prosthetic fitting in 15 patients with amputation through the leg. The foam plaster is poured into a prepared cotton sleeve, with a zip incorporated, and rolled out to a layer 4 mm thick. The filled sleeve is put around the stump and the zip closed, moulding the sleeve firmly to the stump. The closed sleeve hardens into a rigid polyurethane shell within 20 min. Aferwards the skeletal prosthetic components are fixed with the same rigid foam. The polyurethane foam socket is quickly and cleanly prepared, only one third of the weight of a plaster of Paris cast and is easily removed by means of the zip, allowing access to the stump.

  16. Polyurethane foam infill for fiber-reinforced polymer (FRP) bridge deck panels.

    DOT National Transportation Integrated Search

    2014-05-01

    The objective of the proposed research is to develop, test, and evaluate fiber-reinforced, polyurethane foams to replace the costly : honeycomb construction currently used to manufacture FRP bridge deck panels. The effort will focus on developing an ...

  17. Fiber-modified polyurethane foam for ballistic protection

    NASA Technical Reports Server (NTRS)

    Fish, R. H.; Parker, J. A.; Rosser, R. W.

    1975-01-01

    Closed-cell, semirigid, fiber-loaded, self-extinguishing polyurethane foam material fills voids around fuel cells in aircraft. Material prevents leakage of fuel and spreading of fire in case of ballistic incendiary impact. It also protects fuel cell in case of exterior fire.

  18. Modeling of skeletal members using polyurethane foam

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Sena, J.M.F.; Weaver, R.W.

    1983-11-01

    At the request of the University of New Mexico's Maxwell Museum of Anthropology, members of the Plastic Section in the Process Development Division at SNLA undertook the special project of the Chaco Lady. The project consisted of polyurethane foam casting of a disinterred female skull considered to be approximately 1000 years old. Rubber latex molds, supplied by the UNM Anthropology Department, were used to produce the polymeric skull requested. The authors developed for the project a modified foaming process which will be used in future polyurethane castings of archaeological artifacts and contemporary skeletal members at the University.

  19. Solvent stimulated actuation of polyurethane-based shape memory polymer foams using dimethyl sulfoxide and ethanol

    NASA Astrophysics Data System (ADS)

    Boyle, A. J.; Weems, A. C.; Hasan, S. M.; Nash, L. D.; Monroe, M. B. B.; Maitland, D. J.

    2016-07-01

    Solvent exposure has been investigated to trigger actuation of shape memory polymers (SMPs) as an alternative to direct heating. This study aimed to investigate the feasibility of using dimethyl sulfoxide (DMSO) and ethanol (EtOH) to stimulate polyurethane-based SMP foam actuation and the required solvent concentrations in water for rapid actuation of hydrophobic SMP foams. SMP foams exhibited decreased T g when submerged in DMSO and EtOH when compared to water submersion. Kinetic DMA experiments showed minimal or no relaxation for all SMP foams in water within 30 min, while SMP foams submerged in EtOH exhibited rapid relaxation within 1 min of submersion. SMP foams expanded rapidly in high concentrations of DMSO and EtOH solutions, where complete recovery over 30 min was observed in DMSO concentrations greater than 90% and in EtOH concentrations greater than 20%. This study demonstrates that both DMSO and EtOH are effective at triggering volume recovery of polyurethane-based SMP foams, including in aqueous environments, and provides promise for use of this actuation technique in various applications.

  20. Polymer-Reinforced, Non-Brittle, Lightweight Cryogenic Insulation

    NASA Technical Reports Server (NTRS)

    Hess, David M.

    2013-01-01

    The primary application for cryogenic insulating foams will be fuel tank applications for fueling systems. It is crucial for this insulation to be incorporated into systems that survive vacuum and terrestrial environments. It is hypothesized that by forming an open-cell silica-reinforced polymer structure, the foam structures will exhibit the necessary strength to maintain shape. This will, in turn, maintain the insulating capabilities of the foam insulation. Besides mechanical stability in the form of crush resistance, it is important for these insulating materials to exhibit water penetration resistance. Hydrocarbon-terminated foam surfaces were implemented to impart hydrophobic functionality that apparently limits moisture penetration through the foam. During the freezing process, water accumulates on the surfaces of the foams. However, when hydrocarbon-terminated surfaces are present, water apparently beads and forms crystals, leading to less apparent accumulation. The object of this work is to develop inexpensive structural cryogenic insulation foam that has increased impact resistance for launch and ground-based cryogenic systems. Two parallel approaches will be pursued: a silica-polymer co-foaming technique and a post foam coating technique. Insulation characteristics, flexibility, and water uptake can be fine-tuned through the manipulation of the polyurethane foam scaffold. Silicate coatings for polyurethane foams and aerogel-impregnated polyurethane foams have been developed and tested. A highly porous aerogel-like material may be fabricated using a co-foam and coated foam techniques, and can insulate at liquid temperatures using the composite foam

  1. Shock Tube Test for Energy Absorbing Materials

    DTIC Science & Technology

    2013-09-13

    rigid and lightweight foam material with a closed-cell structure, and a very high strength-to-weight ratio (7). It is commonly used as a sandwich...including application in helmet liners (8). Zorbium™ is the viscoelastic polyurethane foam used in military helmet suspension system pads (9). 8...viscoelastic polyurethane foam which shows strain rate dependent behavior when compressed. This is displayed by the significant difference in response

  2. Inhibition of Microbial Growth by Fatty Amine Catalysts from Polyurethane Foam Test Tube Plugs

    PubMed Central

    Bach, John A.; Wnuk, Richard J.; Martin, Delano G.

    1975-01-01

    When polyurethane foam test tube plugs are autoclaved, they release volatile fatty amines that inhibit the growth of some microorganisms. The chemical structures of these amines were determined by the use of a gas chromatographmass spectrometer. They are catalysts used to produce the foam. The problem of contaminating growth media with toxic substances released from polymeric materials is discussed. PMID:1096816

  3. Experimental study on energy absorption of foam filled kraft paper honeycomb subjected to quasi-static uniform compression loading

    NASA Astrophysics Data System (ADS)

    Abd Kadir, N.; Aminanda, Y.; Ibrahim, M. S.; Mokhtar, H.

    2016-10-01

    A statistical analysis was performed to evaluate the effect of factor and to obtain the optimum configuration of Kraft paper honeycomb. The factors considered in this study include density of paper, thickness of paper and cell size of honeycomb. Based on three level factorial design, two-factor interaction model (2FI) was developed to correlate the factors with specific energy absorption and specific compression strength. From the analysis of variance (ANOVA), the most influential factor on responses and the optimum configuration was identified. After that, Kraft paper honeycomb with optimum configuration is used to fabricate foam-filled paper honeycomb with five different densities of polyurethane foam as filler (31.8, 32.7, 44.5, 45.7, 52 kg/m3). The foam-filled paper honeycomb is subjected to quasi-static compression loading. Failure mechanism of the foam-filled honeycomb was identified, analyzed and compared with the unfilled paper honeycomb. The peak force and energy absorption capability of foam-filled paper honeycomb are increased up to 32% and 30%, respectively, compared to the summation of individual components.

  4. [Modified polyurethane foam as a local hemostatic agent after dental extractions].

    PubMed

    Selten, M H A; Broekema, F I; Zuidema, J; van Oeveren, W; Bos, R R M

    2013-01-01

    In this split mouth experiment, the feasibility ofpolyurethane foam as a local hemostatic agent after dental extractions was studied. Ten healthy patients underwent 2 extractions ofa dental element in 1 treatment session. The 10 patients were subsequently randomly divided in a gelatin group and a collagen group. In the gelatin group, a polyurethane foam (PU) was applied in 1 extraction socket, while in the other socket a commercially available gelatin foam was applied. In the collagen group, a PU was applied in 1 socket, and a collagen wadding in the other. All hemostats were removed after 2 minutes, after which the degree of coagulation was measured using a thrombin/antithrombin test and a fibrinogen test. This study suggests that polyurethane foam has hemostatic capacity. Large scale clinical research is needed to confirm this finding, and should indicate whether this hemostatic capacity is clinically relevant.

  5. Do You Have Work-Related Asthma? A Guide for You and Your Doctor

    MedlinePlus

    ... Polyurethane foam • Paints, lacquers, ink, varnishes, sealants, finishes • Insulation materials • Polyurethane rubber • Glues and adhesives • Car manufacture and repair • Building construction (plaster, insulation) • Foam blowing and cutting • Painting • Truck bed liner ...

  6. Development of test systems for characterizing emissions from spray polyurethane foam insulation (SPFI)

    EPA Science Inventory

    The relationship between onsite manufacture of spray polyurethane foam insulation (SPFI) and potential exposures to diisocyanates, amines, flame retardants (FRs), blowing agents, aldehydes and other organic compounds that may be emitted from SPFI is not well understood. EPA is de...

  7. Roof-crush strength improvement using rigid polyurethane foam

    NASA Astrophysics Data System (ADS)

    Lilley, K.; Mani, A.

    1998-08-01

    Recent bending tests show the effectiveness of rigid, polyurethane foam in improving the strength of automotive body structures. By using foam, it is possible to reduce pillar sections, and to reduce thicknesses or eliminate reinforcements inside the pillars, and thereby offset the mass increase due to the foam filling. Further tests showed that utilizing the foam filling in a B-pillar to reduce section size can save ~20 mm that could be utilized to add energy absorbing structures in order to meet the new interior head impact requirements specified by the federal motor vehicle safety standards (FMVSS) 201 Head Impact Protection upgrade.

  8. Use of polyurethane foam inside plaster casts to prevent the onset of heel sores in the population at risk. A controlled clinical study.

    PubMed

    Forni, Cristiana; Loro, Loretta; Tremosini, Morena; Mini, Sandra; Pignotti, Elettra; Bigoni, Ombretta; Guzzo, Giuseppe; Bellini, Laura; Trofa, Carmela; Di Cataldo, Anna M; Guzzi, Marilena

    2011-03-01

    The aim of this study was to test the effectiveness of polyurethane foam in contact with the heel inside a plaster cast to decrease the rate of pressure sores in the population at most risk. The rate of pressure sores caused by the plaster cast is reported to be 14-15% in the paediatric population, 33.3% in patients having undergone chemotherapy for bone tumours and 43% in orthopaedic patients who already have sore skin when the cast is applied (grade 1 lesion) to the heel. Controlled clinical trial. From November 2007-January 2009, all consecutive subjects requiring lower limb casts having undergone chemotherapy and/or presenting heel soreness received polyurethane foam in contact with the skin of the heel before applying the cast. The results were compared with those of patients with the same risk factors but were not administered the foam and were enrolled from May 2005-August 2006. In total, 156 patients were enrolled, 85 in the control group and 71 in the experimental group. In the experimental group, 2 of the 56 patients (3.6%) with sore skin developed a pressure sore compared with 21 of 49 (42.9%) in the control group without polyurethane foam (p < 0.0005). In the experimental group, one of the 24 patients (4.2%) patients undergoing chemotherapy developed a pressure sore compared with 18 of 54 (33.3%) in the control group (p = 0.005). Placing polyurethane foam in contact with the skin of the heel inside a plaster cast prevents the formation of pressure sores. This study provides evidence that using polyurethane foam to prevent sores even inside plaster casts in populations at most risk is a simple and cost-effective strategy and decreases the discomfort, pain and risks in these patients. © 2011 Blackwell Publishing Ltd.

  9. Primary Stability of Zirconium vs Titanium Implants: An In Vitro Comparison

    DTIC Science & Technology

    2015-06-05

    Zirconia implant and 4x11.5 Titanium implant placed in artificial bone ( polyurethane foam ) at .08 rotations /sec…………………………………28   viii...measurements as they relate to primary Implant Stability. Artificial Bone made of solid ridged polyurethane foam was used as an alternative test...30 pound per cubic foot solid rigid polyurethane blocks used to substitute human cancellous bone

  10. Open-pore polyurethane product

    DOEpatents

    Jefferson, R.T.; Salyer, I.O.

    1974-02-17

    The method is described of producing an open-pore polyurethane foam having a porosity of at least 50% and a density of 0.1 to 0.5 g per cu cm, and which consists of coherent spherical particles of less than 10 mu diam separated by interconnected interstices. It is useful as a filter and oil absorbent. The product is admirably adapted to scavenging of crude oil from the surface of seawater by preferential wicking. The oil-soaked product may then be compressed to recover the oil or burned for disposal. The crosslinked polyurethane structures are remarkably solvent and heat-resistance as compared with known thermoplastic structures. Because of their relative inertness, they are useful filters for gasoline and other hydrocarbon compounds. (7 claims)

  11. Periodic processes in vapor phase biofiltration

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Moe, W.M.; Irvine, R.L.

    1998-07-01

    Most industrial processes and environmental remediation activities generate large volumes of air contaminated with low concentrations of volatile organic compounds. Carbon adsorption is the most widely used conventional treatment technology, but it has many drawbacks including secondary waste streams and excessive regeneration costs. Biofiltration, a microbial-based treatment technology, removes and biodegrades contaminants from a wide variety of waste streams without the disadvantages of carbon adsorption. In biofiltration, contaminated air flows through a packed bed containing microorganisms which convert contaminants primarily into carbon dioxide, water, and biomass. This paper describes how periodically operated, controlled unsteady state conditions were imposed on biofiltersmore » which used a new polyurethane foam medium that couples high porosity, suitable pore size, and low density with an ability to sorb water. The potential benefits associated with the controlled, unsteady-state operation of biofilters containing this new polyurethane foam medium are described herein. An example system treating a toluene contaminated waste gas is presented.« less

  12. Experience gained from the use of polyurethane foam-insulated pipelines at OAO Moscow Heating-Network Company

    NASA Astrophysics Data System (ADS)

    Kashinskii, V. I.; Lipovskikh, V. M.; Rotmistrov, Ya. G.

    2007-07-01

    Results from 10 years of experience using polyurethane foam-insulated pipelines at OAO Moscow Heating-Network Co. are presented. It is shown that the failure rate of such pipelines is considerably lower than that of pipelines laid in conduits.

  13. Rigid polyurethane and kenaf core composite foams

    USDA-ARS?s Scientific Manuscript database

    Rigid polyurethane foams are valuable in many construction applications. Kenaf is a bast fiber plant where the surface stem skin provides bast fibers whose strength-to-weight ratio competes with glass fiber. The higher volume product of the kenaf core is an under-investigated area in composite appli...

  14. Rigid polyurethane foam/cellulose whisker nanocomposites: preparation, characterization, and properties.

    PubMed

    Li, Yang; Ren, Hongfeng; Ragauskas, Arthur J

    2011-08-01

    Novel rigid polyurethane nanocomposite foams have been prepared by the polymerization of a sucrose-based polyol, a glycerol-based polyol and polymeric diphenylmethane diisocyanate in the presence of cellulose whiskers. Varying amounts of sulfuric acid hydrolyzed cellulose whiskers (0.25, 0.50, 0.75 and 1.00 wt%) prepared from a commercial fully bleached softwood kraft pulp were incorporated to investigate the effect of its dosage on the mechanical and thermal properties of polyurethane nanocomposites. Fourier transform infrared spectra of the nanocomposite foams suggested that additional hydrogen bonds were developed and crosslinking occurred between the hydroxyl groups of cellulose whiskers and isocyanate groups which increased the phase separation of soft and hard segments in the polyurethane. The closed cells of control foam and nanocomposite foams were homogeneously dispersed and the cell sizes were approximately 350 microm in diameter as observed by scanning electron microscope. A substantial improvement of mechanical properties at low whisker content (< or = 1.00 wt%) was obtained, especially the compressive strength and modulus at 1.00 wt% whiskers content which were increased by 269.7% and 210.0%, respectively. Thermal stability of the nanocomposites was also enhanced as determined by differential scanning calorimetry and thermogravimetric analysis.

  15. Sodium hydrogen carbonate as an alternative blowing agent in the preparation of palm-based polyurethane foam

    NASA Astrophysics Data System (ADS)

    Shakir, Amira Shakim Abdul; Badri, Khairiah Haji; Hua, Chia Chin

    2016-11-01

    An environmental-friendly blowing agent has been used to fabricate flexible polyurethane (PU) foam. Polyurethane foam was prepared from palm kernel oil-based monoester polyol (PKO-p) via prepolymerization method. Acetone has been used as solvent in this study. The developed polyurethane foam was characterized using tensile, differential scanning calorimetry analysis (DSC), thermogravimetric analysis (TGA), optical microscope and drop shape analyzer. The mechanical properties of the PU-reference (PU-R) and PU-NaHCO3 foam was analyzed by tensile using ASTM D 3574-01. From the results, the elongation of PU- NaHCO3 shows reduction to 26.3 % compared to PU-R. The DSC showed two glass transition temperatures in all samples that belonged to the PU-R and PU-NaHCO3. TGA revealed that the incorporation of sodium hydrogen carbonate into the PU system did not show significant difference as compared to the control PU. The morphology of both PU was investigated using optical microscope. Contact angle has been measured to determine the hydrophobicity of the PU. The PU- NaHCO3 exhibited an increase in contact angle (93.1°).

  16. Ventilation Guidance To Promote the Safe Use of Spray Polyurethane Foam (SPF) Insulation, Incluyendo la Versión de Español

    EPA Pesticide Factsheets

    This guidance describes basic ventilation principles and strategies to help protect workers and building occupants and promote the safe use of spray polyurethane foam (SPF) insulation. Guia para la ventilacion sobre la application del aerosol de espuma.

  17. 78 FR 68055 - Information Collection Request Submitted to OMB for Review and Approval; Comment Request; NESHAP...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2013-11-13

    ... Polyurethane Foam Production and Fabrication, Lead Acid Battery Manufacturing, and Wood Preserving (Renewal... Polyurethane Foam Production and Fabrication, Lead Acid Battery Manufacturing, and Wood Preserving (40 CFR Part... battery manufacturing facilities, and 393 existing wood preserving facilities. The total annual responses...

  18. Washing Off Polyurethane Foam Insulation

    NASA Technical Reports Server (NTRS)

    Burley, Richard K.; Fogel, Irving

    1990-01-01

    Jet of hot water removes material quickly and safely. Simple, environmentally sound technique found to remove polyurethane foam insulation from metal parts. Developed for (but not limited to) use during rebuilding of fuel system of Space Shuttle main engine, during which insulation must be removed for penetrant inspection of metal parts.

  19. A sticky situation: management of spray polyurethane foam insulation in body orifices.

    PubMed

    Sowerby, Robert J; Sowerby, Leigh J; Vinden, Chris

    2011-11-01

    Spray polyurethane foam insulation is commonly used in the construction industry to fill gaps, seal, and insulate. We present three cases of intentional spray foam insertion in body orifices and discuss the management of such situations in the emergency department. This series includes a case of oral foam insertion used in a suicide attempt by suffocation and two cases of rectal insertion. All of these cases had potential long-term consequences; one was life-threatening. To our knowledge, this is the first published report on the medical management and removal of foam insulation from body orifices. In all three cases, the foam insulation material was successfully removed after allowing the material to harden.

  20. Investigation of the Minimum Deployment Time of a Foam/Fabric Composite Material.

    DTIC Science & Technology

    1980-09-01

    Kevlar Fabric! use xperienced, trained personnel. The pres- Polyurethane Foam Composites. TR M-272/ADA076310 sure containers should be adequately...evaluated. High molecular ponent foam producing materials. (Polyurethanes, weight resin performed best because its solubility char- epoxies, phenolics , and...that was coated to a total Because earlier CERL tests had established the weight of about 10 oz/sq yd (237 gm/m 2 ). strength of Kevlar * fabric, it was

  1. Investigation on the mechanical properties of palm-based flexible polyurethane foam

    NASA Astrophysics Data System (ADS)

    On, Ahmad Zuhdi Mohd; Badri, Khairiah Haji

    2015-09-01

    A series of modification polyurethane (PU) system was prepared by introducing palm kernel based polyol (PKO-p) to progressively replaced commercial polyether polyol from petrochemical based material. This paper describes the effect of PKO-p on the physical-mechanical properties of polyurethane foams. Stress-strain analysis in tensile mode was conducted with physicochemical analysis by performing Fourier transform infrared (FTIR). The morphological studies were observed by the optical microscope. The foam showed an increment on the modulus up to 458.3kPa as more incorporation of PKO-p introduced to the system. In contrast, tensile strength of PU foam depicted the highest up to 162 kPa at 60:40. The elongation at break showed decrement as the composition of the renewable polyol increased to a ratio 60/40 of PKO-p to petrochemical based polyol.

  2. Strain compatibility tests for sprayed foam cryogenic insulation

    NASA Technical Reports Server (NTRS)

    Hill, W. L.; Kimberlin, D. O.

    1970-01-01

    Mechanical stress applied to foam-coated aluminum alloy specimens maintained at cryogenic temperature simulates actual use conditions of the foam insulation. The testing reveals defects in the polyurethane foam or in the foam to metal bond.

  3. Parameters estimation of sandwich beam model with rigid polyurethane foam core

    NASA Astrophysics Data System (ADS)

    Barbieri, Nilson; Barbieri, Renato; Winikes, Luiz Carlos

    2010-02-01

    In this work, the physical parameters of sandwich beams made with the association of hot-rolled steel, Polyurethane rigid foam and High Impact Polystyrene, used for the assembly of household refrigerators and food freezers are estimated using measured and numeric frequency response functions (FRFs). The mathematical models are obtained using the finite element method (FEM) and the Timoshenko beam theory. The physical parameters are estimated using the amplitude correlation coefficient and genetic algorithm (GA). The experimental data are obtained using the impact hammer and four accelerometers displaced along the sample (cantilevered beam). The parameters estimated are Young's modulus and the loss factor of the Polyurethane rigid foam and the High Impact Polystyrene.

  4. Numerical Simulation of Ballistic Impact of Layered Aluminum Nitride Ceramic

    DTIC Science & Technology

    2015-09-01

    tile(s) Aluminum nitride (AlN) 163 a Polymer layers Polyurethane foam 18 b Backing metal Aluminum 6061-T6 (Al) 23 c Projectile Tungsten heavy alloy...larger (a factor of 3.8) than the most dense polyurethane foam of the available constitutive models. Default options for element failure were imposed in...AlN), a polycrystalline ceramic. The total thickness of the tile(s) is 38.1 mm in all cases. A thin polyurethane laminate separates neighboring tiles

  5. 77 FR 56639 - Certain New Chemicals; Receipt and Status Information

    Federal Register 2010, 2011, 2012, 2013, 2014

    2012-09-13

    ... notice end Manufacturer/ Use Chemical date date importer P-12-0488 08/01/2012 10/29/2012 CBI (G) Additive... 10/29/2012 CBI (G) Additive to (G) Hydroxy polyurethane containing oil, foam. polymer with alkylene.../2012 CBI (G) Additive to (G) Alkanol, polyurethane oxybis-, foam. polymer with aromatic isocyanate...

  6. MANUAL: BEST MANAGEMENT PRACTICES FOR POLLUTION PREVENTION IN THE SLABSTOCK AND MOLDED FLEXIBLE POLYURETHANE FOAM INDUSTRY

    EPA Science Inventory

    The 1990 Clean Air Act Amendments require EPA to develop standards for major emission sources of 189 hazardous air pollutants (HAPs). EPA has identified the flexible polyurethane foam industry as a large emitter of HAPs and has slated the industry for regulation under Title III, ...

  7. Sorption of Triangular Silver Nanoplates on Polyurethane Foam

    NASA Astrophysics Data System (ADS)

    Furletov, A. A.; Apyari, V. V.; Garshev, A. V.; Volkov, P. A.; Tolmacheva, V. V.; Dmitrienko, S. G.

    2018-02-01

    The sorption of triangular silver nanoplates on polyurethane foam is investigated as a procedure for creating a nanocomposite sensing material for subsequent use in optical means of chemical analysis. Triangular silver nanoplates are synthesized and characterized, and a simple sorption technique for the formation of a composite material based on these nanoplates is proposed.

  8. A multilayered polyurethane foam technique for skin graft immobilization.

    PubMed

    Nakamura, Motoki; Ito, Erika; Kato, Hiroshi; Watanabe, Shoichi; Morita, Akimichi

    2012-02-01

    Several techniques are applicable for skin graft immobilization. Although the sponge dressing is a popular technique, pressure failure near the center of the graft is a weakness of the technique that can result in engraftment failure. To evaluate the efficacy of a new skin graft immobilization technique using multilayered polyurethane foam in vivo and in vitro. Twenty-six patients underwent a full-thickness skin graft. Multiple layers of a hydrocellular polyurethane foam dressing were used for skin graft immobilization. In addition, we created an in vitro skin graft model that allowed us to estimate immobilization pressure at the center and edges of skin grafts of various sizes. Overall mean graft survival was 88.9%. In the head and neck region (19 patients), mean graft survival was 93.6%. Based on the in vitro outcomes, this technique supplies effective pressure (<30 mmHg) to the center region of the skin graft. This multilayered polyurethane foam dressing is simple, safe, and effective for skin graft immobilization. © 2011 by the American Society for Dermatologic Surgery, Inc. Published by Wiley Periodicals, Inc.

  9. Preparation and energy-saving application of polyurethane/phase change composite materials for electrical water heaters

    NASA Astrophysics Data System (ADS)

    Hu, Yougen; Zhao, Tao; Wu, Xiaolin; Lai, Maobai; Jiang, Chengming; Sun, Rong

    2011-11-01

    Thermal energy storage plays an important role in heat management because of the demand for developed energy conservation, and has applications in diverse areas, from buildings to textiles and clothings. In this study, we aimed to improve thermal characteristics of polyurethane rigid foams that have been widely used for thermal insulation in electrical water heaters. Through this work, paraffin waxes with melting point of 55~65°C act as phase change materials. Then the phase change materials were incorporated into the polyurethane foams at certain ratio. The polyurethane/phase change composite materials used as insulation layers in electrical water heaters performed the enthalpy value of 5~15 J/g. Energy efficiency of the electrical water heaters was tested according to the National Standard of China GB 21519-2008. Results show that 24 h energy consumption of the electrical water heaters manufactured by traditional polyurethane rigid foams and polyurethane/phase change material composites was 1.0612 kWh and 0.9833 kWh, respectively. The results further show that the energy-saving rate is 7.36%. These proved that polyurethane/phase change composite materials can be designed as thermal insulators equipped with electrical water heaters and have a significant effect on energy conservation.

  10. Preparation and energy-saving application of polyurethane/phase change composite materials for electrical water heaters

    NASA Astrophysics Data System (ADS)

    Hu, Yougen; Zhao, Tao; Wu, Xiaolin; Lai, Maobai; Jiang, Chengming; Sun, Rong

    2012-04-01

    Thermal energy storage plays an important role in heat management because of the demand for developed energy conservation, and has applications in diverse areas, from buildings to textiles and clothings. In this study, we aimed to improve thermal characteristics of polyurethane rigid foams that have been widely used for thermal insulation in electrical water heaters. Through this work, paraffin waxes with melting point of 55~65°C act as phase change materials. Then the phase change materials were incorporated into the polyurethane foams at certain ratio. The polyurethane/phase change composite materials used as insulation layers in electrical water heaters performed the enthalpy value of 5~15 J/g. Energy efficiency of the electrical water heaters was tested according to the National Standard of China GB 21519-2008. Results show that 24 h energy consumption of the electrical water heaters manufactured by traditional polyurethane rigid foams and polyurethane/phase change material composites was 1.0612 kWh and 0.9833 kWh, respectively. The results further show that the energy-saving rate is 7.36%. These proved that polyurethane/phase change composite materials can be designed as thermal insulators equipped with electrical water heaters and have a significant effect on energy conservation.

  11. Histological evaluation of capsules formed by silicon implants coated with polyurethane foam and with a textured surface in rats.

    PubMed

    Silva, Eduardo Nascimento; Ribas-Filho, Jurandir Marcondes; Czeczko, Nicolau Gregori; Pachnicki, Jan Pawel Andrade; Netto, Mário Rodrigues Montemor; Lipinski, Leandro Cavalcante; Noronha, Lucia de; Colman, Joelmir; Zeni, João Otavio; Carvalho, Caroline Aragão de

    2016-12-01

    To assess the capsules formed by silicone implants coated with polyurethane foam and with a textured surface. Sixty-four Wistar albinus rats were divided into two groups of 32 each using polyurethane foam and textured surface. The capsules around the implants were analyzed for 30, 50, 70 and 90 days. Were analyzed the following parameters: foreign body reaction, granulation tissue, presence of myofibroblasts, neoangiogenesis, presence of synovial metaplasia, capsular thickness, total area and collagen percentage of type I and III, in capsules formed around silicone implants in both groups. The foreign body reaction was only present in the four polyurethane subgroups. The formation of granulation tissue and the presence of myofibroblasts were higher in the four polyurethane subgroups. Regarding to neoangiogenesis and synovial metaplasia, there was no statistical difference between the groups. Polyurethane group presented (all subgroups) a greater capsule thickness, a smaller total area and collagen percentage of type I and a higher percentage area of type III, with statistical difference. The use of polyurethane-coated implants should be stimulated by the long-term results in a more stable capsule and a lower incidence of capsular contracture, despite developing a more intense and delayed inflammatory reaction in relation to implants with textured surface.

  12. Polyurethane-derived N-doped porous carbon with interconnected sheet-like structure as polysulfide reservoir for lithium-sulfur batteries

    NASA Astrophysics Data System (ADS)

    Xiao, Suo; Liu, Songhang; Zhang, Jianqiu; Wang, Yong

    2015-10-01

    Environmental pollution and energy deficiency are two key issues for the sustainable development of the modern society. Polyurethane foam is a typical commercial polymer with a large production quantity and its waste needs to be recycled. Lithium-sulfur battery is a promising energy-storage device with high energy density and low cost, but its demerits such as poor conductivity of the sulfur and severe capacity degradation due to the soluble lithium polysulfides are still a big challenge. This work reports a facile method to prepare nitrogen-doped porous carbon (NPC) from the polyurethane foam (PUF) waste and use it as a reservoir to impregnate sulfur for lithium-sulfur batteries. The obtained NPC has a unique interconnected sheet-like porous morphology with a large surface area of 1315 m2 g-1. The NPC-S composite delivers a large reversible capacity of 1118 mAh g-1 with good cycling performances and excellent high-rate capabilities. A large reversible capacity of 460 mAh g-1 can be retained at a large current of 5C (8.35 A g-1) after 100 cycles.

  13. Managing burn wounds with SMARTPORE Technology polyurethane foam: two case reports.

    PubMed

    Imran, Farrah-Hani; Karim, Rahamah; Maat, Noor Hidayah

    2016-05-12

    Successful wound healing depends on various factors, including exudate control, prevention of microbial contaminants, and moisture balance. We report two cases of managing burn wounds with SMARTPORE Technology polyurethane foam dressing. In Case 1, a 2-year-old Asian girl presented with a delayed (11 days) wound on her right leg. She sustained a thermal injury from a hot iron that was left idle on the floor. Clinical inspection revealed an infected wound with overlying eschar that traversed her knee joint. As her parents refused surgical debridement under general anesthesia, hydrotherapy and wound dressing using SMARTPORE Technology Polyurethane foam were used. Despite the delay in presentation of this linear thermal pediatric burn injury that crossed the knee joint, the patient's response to treatment and its outcome were highly encouraging. She was cooperative and tolerated each dressing change without the need of supplemental analgesia. Her wound was healed by 24 days post-admission. In Case 2, a 25-year-old Asian man presented with a mixed thickness thermal flame burn on his left leg. On examination, the injury was a mix of deep and superficial partial thickness burn, comprising approximately 3% of his total body surface area. SMARTPORE Technology polyurethane foam was used on his wound; his response to the treatment was very encouraging as the dressing facilitated physiotherapy and mobility. The patient rated the pain during dressing change as 2 on a scale of 10 and his pain score remained the same in every subsequent change. His wound showed evidence of epithelialization by day 7 post-burn. There were no adverse events reported. Managing burn wounds with SMARTPORE Technology polyurethane foam resulted in reduced pain during dressing changes and the successful healing of partial and mixed thickness wounds. The use of SMARTPORE Technology polyurethane foam dressings showed encouraging results and requires further research as a desirable management option in burn wounds.

  14. Effects of oxygen and water content on microbial distribution in the polyurethane foam cubes of a biofilter for SO2 removal.

    PubMed

    Zhang, Jingying; Li, Lin; Liu, Junxin; Wang, Yanjie

    2018-01-01

    The performance of a biofilter for off-gas treatment relies on the activity of microorganisms and adequate O 2 and H 2 O. In present study, a microelectrode was applied to analyze O 2 in polyurethane foam cubes (PUFCs) packed in a biofilter for SO 2 removal. The O 2 distribution varied with the density and water-containing rate (WCR) of PUFCs. The O 2 concentration dropped sharply from 10.2 to 0.8mg/L from the surface to the center of a PUFC with 97.20% of WCR. The PUFCs with high WCR presented aerobic-anoxic-aerobic areas. Three-dimensional simulated images demonstrated that the structure of PUFCs with high WCR consisted of an aerobic "shell" and an anoxic "core", with high-density PUFCs featuring a larger anoxic area than low-density PUFCs. Moreover, the H 2 O distribution in the PUFC was uneven and affected the O 2 concentration. Whereas aerobic bacteria were observed in the PUFC surface, facultative anaerobic microorganisms were found at the PUFC core, where the O 2 concentration was relatively low. O 2 and H 2 O distributions differed in the PUFCs, and the distribution of microorganisms varied accordingly. Copyright © 2017. Published by Elsevier B.V.

  15. Preparation and evaluation of polyurethane/cellulose nanowhisker bimodal foam nanocomposites for osteogenic differentiation of hMSCs.

    PubMed

    Shahrousvand, Ehsan; Shahrousvand, Mohsen; Ghollasi, Marzieh; Seyedjafari, Ehsan; Jouibari, Iman Sahebi; Babaei, Amir; Salimi, Ali

    2017-09-01

    Biocompatible and biodegradable polyurethanes (PUs) based on polycaprolactone diol (PCL) were prepared and filled with cellulose nanowhiskers (CNWs) obtained from wastepaper. The incorporated polyurethane nanocomposites were used to prepare foamed scaffolds with bimodal cell sizes through solvent casting/particulate leaching method. Sodium chloride and sugar porogens were also prepared to fabricate the scaffolds. The mechanical and thermal properties of PU/CNW nanocomposites were investigated. Incorporation of different CNWs resulted in various structures with tunable mechanical properties and biodegradability. All bimodal foam nanocomposites were biodegradable and also non-cytotoxic as revealed by MTT assay using SNL fibroblast cell line. PU/CNW foam scaffolds were used for osteogenic differentiation of human mesenchymal stem cells (hMSCs). Based on the results, such PU/CNW nanocomposites could support proliferation and osteogenic differentiation of hMSCs in three-dimensional synthetic extracellular matrix (ECM). Copyright © 2017 Elsevier Ltd. All rights reserved.

  16. In vivo tissue response following implantation of shape memory polyurethane foam in a porcine aneurysm model

    PubMed Central

    Rodriguez, Jennifer N.; Clubb, Fred J.; Wilson, Thomas S.; Miller, Matthew W.; Fossum, Theresa W.; Hartman, Jonathan; Tuzun, Egemen; Singhal, Pooja; Maitland, Duncan J.

    2014-01-01

    Cerebral aneurysms treated by traditional endovascular methods using platinum coils have a tendency to be unstable, either due to chronic inflammation, compaction of coils, or growth of the aneurysm. We propose to use alternate filling methods for the treatment of intracranial aneurysms using polyurethane based shape memory polymer (SMP) foams. SMP polyurethane foams were surgically implanted in a porcine aneurysm model to determine biocompatibility, localized thrombogenicity, and their ability to serve as a stable filler material within an aneurysm. The degree of healing was evaluated via gross observation, histopathology and low vacuum scanning electron microscopy (LV-SEM) imaging after zero, thirty and ninety days. Clotting was initiated within the SMP foam at time zero (less than one hour exposure to blood prior to euthanization), partial healing was observed at thirty days, and almost complete healing had occurred at ninety days in vivo, with minimal inflammatory response. PMID:23650278

  17. In vivo response to an implanted shape memory polyurethane foam in a porcine aneurysm model.

    PubMed

    Rodriguez, Jennifer N; Clubb, Fred J; Wilson, Thomas S; Miller, Matthew W; Fossum, Theresa W; Hartman, Jonathan; Tuzun, Egemen; Singhal, Pooja; Maitland, Duncan J

    2014-05-01

    Cerebral aneurysms treated by traditional endovascular methods using platinum coils have a tendency to be unstable, either due to chronic inflammation, compaction of coils, or growth of the aneurysm. We propose to use alternate filling methods for the treatment of intracranial aneurysms using polyurethane-based shape memory polymer (SMP) foams. SMP polyurethane foams were surgically implanted in a porcine aneurysm model to determine biocompatibility, localized thrombogenicity, and their ability to serve as a stable filler material within an aneurysm. The degree of healing was evaluated via gross observation, histopathology, and low vacuum scanning electron microscopy imaging after 0, 30, and 90 days. Clotting was initiated within the SMP foam at time 0 (<1 h exposure to blood before euthanization), partial healing was observed at 30 days, and almost complete healing had occurred at 90 days in vivo, with minimal inflammatory response. Copyright © 2013 Wiley Periodicals, Inc.

  18. Final Report: Research Study on Development of Environmental Friendly Spray-on Foam Insulation (SOFI) for the External Tank (ET)

    NASA Technical Reports Server (NTRS)

    Stuckey, James M.

    1996-01-01

    The selection and quantification of four foams using a more environmentally friendly HCFC-141b blowing agent replacing foams that used the CFC-11 blowing agent for the external tank (ET) LWT has been addressed along with problems and solutions that were encountered during verification. The effort on two lower density spray foams for the ET SLWT are presented, but predicted weight savings were not encouraging. Suggestions for possible problem solving are included along with a new approach for selecting foams for qualification as back-up foams for the foams used on the ET LWT. We investigated three resins for use as thermally sprayed coatings for corrosion prevention on metal. The best coating was obtained with a thermoplastic polyimide resin. This coating has a good chance of meeting ET requirements. Possible third generation blowing agents have been shown usable in polyurethane spray and pour foams, and solubility in isocyannate foam components are acceptable. We considered aerogels as insulation materials on space vehicles, and suggested a liner for a liquid oxygen (LOX) composite tank.

  19. 78 FR 36773 - Agency Information Collection Activities; Submission to OMB for Review and Approval; Comment...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2013-06-19

    ... Activities; Submission to OMB for Review and Approval; Comment Request; NESHAP for Flexible Polyurethane Foam... Reading Room is open from 8:30 a.m. to 4:30 p.m., Monday through Friday, excluding legal holidays. The... www.regulations.gov . Title: NESHAP for Flexible Polyurethane Foam Production (Renewal) ICR Numbers...

  20. 77 FR 37901 - Agency Information Collection Activities; Submission to OMB for Review and Approval; Comment...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2012-06-25

    ... Activities; Submission to OMB for Review and Approval; Comment Request; NESHAP for Flexible Polyurethane Foam... Constitution Avenue NW., Washington, DC. The EPA Docket Center Public Reading Room is open from 8:30 a.m. to 4... Flexible Polyurethane Foam Fabrication (Renewal). ICR Numbers: EPA ICR Number 2027.05, OMB Control Number...

  1. Assessment of mitigating transverse joint faulting on portland cement concrete pavement with polyurethane foam on LA 1 Bypass, state project number 034-30-0023.

    DOT National Transportation Integrated Search

    2015-02-01

    A case study was conducted by the Louisiana Transportation Research Center (LTRC) to assess the effectiveness of reducing faulting on jointed concrete : pavement (JCP) with polyurethane foam (PF) on LA 1 Bypass, S.P. 034-30-0023. The PF fault correct...

  2. Checklist of Safe Work Practices for Spray Polyurethane Foam (SPF) for Contractors, Incluyendo la Versión de Español

    EPA Pesticide Factsheets

    A contractor checklist aimed at helping spray polyurethane foam (SPF) professional contractors protect themselves, workers and others. Guía de las prácticas seguras en el lugar de trabajo para la aplicación del aerosol de espuma aislante de poliuretano.

  3. 40 CFR 63.8830 - What definitions apply to this subpart?

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... (CONTINUED) National Emission Standards for Hazardous Air Pollutants: Flexible Polyurethane Foam Fabrication... chemical substance that is applied for the purpose of bonding foam to foam, foam to fabric, or foam to any... means the process of bonding flexible foam to one or more layers of material by heating the foam surface...

  4. 40 CFR 63.8830 - What definitions apply to this subpart?

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... (CONTINUED) National Emission Standards for Hazardous Air Pollutants: Flexible Polyurethane Foam Fabrication... chemical substance that is applied for the purpose of bonding foam to foam, foam to fabric, or foam to any... means the process of bonding flexible foam to one or more layers of material by heating the foam surface...

  5. 40 CFR 63.8830 - What definitions apply to this subpart?

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... (CONTINUED) National Emission Standards for Hazardous Air Pollutants: Flexible Polyurethane Foam Fabrication... chemical substance that is applied for the purpose of bonding foam to foam, foam to fabric, or foam to any... means the process of bonding flexible foam to one or more layers of material by heating the foam surface...

  6. 40 CFR 63.8830 - What definitions apply to this subpart?

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... (CONTINUED) National Emission Standards for Hazardous Air Pollutants: Flexible Polyurethane Foam Fabrication... chemical substance that is applied for the purpose of bonding foam to foam, foam to fabric, or foam to any... means the process of bonding flexible foam to one or more layers of material by heating the foam surface...

  7. 40 CFR 63.8830 - What definitions apply to this subpart?

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... (CONTINUED) National Emission Standards for Hazardous Air Pollutants: Flexible Polyurethane Foam Fabrication... chemical substance that is applied for the purpose of bonding foam to foam, foam to fabric, or foam to any... means the process of bonding flexible foam to one or more layers of material by heating the foam surface...

  8. Synthesis of Lipid Based Polyols from 1-butene Metathesized Palm Oil for Use in Polyurethane Foam Applications

    NASA Astrophysics Data System (ADS)

    Sasidharan Pillai, Prasanth Kumar

    This thesis explores the use of 1-butene cross metathesized palm oil (PMTAG) as a feedstock for preparation of polyols which can be used to prepare rigid and flexible polyurethane foams. PMTAG is advantageous over its precursor feedstock, palm oil, for synthesizing polyols, especially for the preparation of rigid foams, because of the reduction of dangling chain effects associated with the omega unsaturated fatty acids. 1-butene cross metathesis results in shortening of the unsaturated fatty acid moieties, with approximately half of the unsaturated fatty acids assuming terminal double bonds. It was shown that the associated terminal OH groups introduced through epoxidation and hydroxylation result in rigid foams with a compressive strength approximately 2.5 times higher than that of rigid foams from palm and soybean oil polyols. Up to 1.5 times improvement in the compressive strength value of the rigid foams from the PMTAG polyol was further obtained following dry and/or solvent assisted fractionation of PMTAG in order to reduce the dangling chain effects associated with the saturated components of the PMTAG. Flexible foams with excellent recovery was achieved from the polyols of PMTAG and the high olein fraction of PMTAG indicating that these bio-derived polyurethane foams may be suitable for flexible foam applications. PMTAG polyols with controlled OH values prepared via an optimized green solvent free synthetic strategy provided flexible foams with lower compressive strength and higher recovery; i.e., better flexible foam potential compared to the PMTAG derived foams with non-controlled OH values. Overall, this study has revealed that the dangling chain issues of vegetable oils can be addressed in part using appropriate chemical and physical modification techniques such as cross metathesis and fractionation, respectively. In fact, the rigidity and the compressive strength of the polyurethane foams were in very close agreement with the percentage of terminal hydroxyl and OH value of the polyol. The results obtained from the study can be used to convert PMTAG like materials into industrially valuable materials.

  9. Degradation of pentachlorophenol by polyurethane-immobilized Flavobacterium cells.

    PubMed Central

    O'Reilly, K T; Crawford, R L

    1989-01-01

    Polyurethane-immobilized Flavobacterium cells (ATCC 39723) degraded pentachlorophenol (PCP) at initial concentrations as high as 300 mg liter-1. The reversible binding of PCP to the polyurethane was shown to be important in the protection of the cells from inhibition of PCP degradation. The degradation activity of the bacteria was monitored for 150 days in semicontinuous batch reactors. The degradation rate dropped by about 0.6% per day. PCP was degraded in a continuous-culture bioreactor at a rate of 3.5 to 4 mg g of foam-1 day-1 for 25 days. Electron micrographs of the polyurethane suggested that the cells were entrapped within 50- to 500-microns-diameter pockets in the foam. PMID:2508552

  10. Improving the mechanical performance of wood fiber reinforced bio-based polyurethane foam

    NASA Astrophysics Data System (ADS)

    Chang, Li-Chi

    Because of the environmental impact of fossil fuel consumption, soybean-based polyurethane (PU) foam has been developed as an alternative to be used as the core in structural insulated panels (SIPs). Wood fibers can be added to enhance the resistance of foam against bending and buckling in compression. The goal of this work is to study the effect of three modifications: fiber surface treatment, catalyst choice, and mixing method on the compression performance of wood fiber-reinforced PU foam. Foams were made with a free-rising process. The compression performance of the foams was measured and the foams were characterized using Fourier transform infrared spectroscopy (FTIR), scanning electron microscopy (SEM), and X-ray computed tomography (CT). The foam reinforced with alkali-treated fibers had improved compression performance. The foams made with various catalysts shared similar performance. The foam made using a mechanical stirrer contained well-dispersed fibers but the reinforcing capability of the fibers was reduced.

  11. Tracking composition of microbial communities for simultaneous nitrification and denitrification in polyurethane foam.

    PubMed

    Chen, Yuan; Wang, Li; Ma, Fang; Yang, Ji-xian; Qiu, Shan

    2014-01-01

    The process of simultaneous nitrification and denitrification (SND) of immobilized microorganisms in polyurethane form is discussed. The effect of different positions within the polyurethane carrier on microbial community response for the SND process is investigated by a combination of denaturing gradient gel electrophoresis profiles of the 16S rRNA gene V3 region and scanning electron microscopy. Results show that polyurethane, which consists of a unique porous structure, is an ideal platform for biofilm stratification of aerobe, anaerobe and facultative microorganisms in regard to the SND process. The community structure diversity response to different positions was distinct. The distributions of various functional microbes, detected from the surface aerobic stratification to the interior anaerobic stratification of polyurethane, were mainly nitrifying and denitrifying bacteria. Meanwhile aerobic denitrifying bacteria such as Paracoccus sp., Agrobacterium rubi and Ochrobactrum sp. were also adhered to the interior and surface of polyurethane. The SND process occurring on polyurethane foam was carried out by two independent processes: nitrogen removal and aerobic denitrification.

  12. Plastic Materials for Insulating Applications.

    ERIC Educational Resources Information Center

    Wang, S. F.; Grossman, S. J.

    1987-01-01

    Discusses the production and use of polymer materials as thermal insulators. Lists several materials that provide varying degrees of insulation. Describes the production of polymer foam and focuses on the major applications of polystyrene foam, polyurethane foam, and polyisocyanurate foam. (TW)

  13. Direct determination of gallium on polyurethane foam by X-ray fluorescence.

    PubMed

    Carvalho, M S; Medeiros, J A; Nóbrega, A W; Mantovano, J L; Rocha, V P

    1995-01-01

    Gallium chloride is easily extracted from 6M HCl by comminuted polyether-type polyurethane foam. After the extraction step, the gallium absorbed by the PU foam can be quantitatively determined by X-ray fluorescence. A procedure for the direct determination of gallium absorbed by PU foam by XRFS is thus described. Gallium is determined at levels as low as 60 ng/ml (C(L)), with a calibration sensitivity of 424 cps ml/mug, within a linear range 0.1-2.30 mug/ml. The procedure investigated was successfully applied to determination of gallium in aluminum alloys, bauxite and industrial residue samples.

  14. Self-Calibrating, Variable-Flow Pumping System

    NASA Technical Reports Server (NTRS)

    Walls, Joe T.

    1994-01-01

    Pumping system provides accurate, controlled flows of two chemical liquids mixed in spray head and react to form rigid or flexible polyurethane or polyisocyanurate foam. Compatible with currently used polyurethane-based coating materials and gas-bubble-forming agents (called "blowing agents" in industry) and expected to be compatible with materials that used in near future. Handles environmentally acceptable substitutes for chlorofluorocarbon foaming agents.

  15. Polymer compositions and methods

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Allen, Scott D.; Willkomm, Wayne R.

    The present invention encompasses polyurethane compositions comprising aliphatic polycarbonate chains. In one aspect, the present invention encompasses polyurethane foams, thermoplastics and elastomers derived from aliphatic polycarbonate polyols and polyisocyanates wherein the polyol chains contain a primary repeating unit having a structure: ##STR00001## In another aspect, the invention provides articles comprising the inventive foam and elastomer compositions as well as methods of making such compositions.

  16. Cyanide toxicity from the thermal degradation of rigid polyurethane foam.

    PubMed

    Bell, R H; Stemmer, K L; Barkley, W; Hollingsworth, L D

    1979-09-01

    Thermal degradation products (tdp) from a model, rigid polyurethane foam were collected in such a manner as to eliminate carbon monoxide and other gases with low boiling points. The effects in rats resulting from intratracheal intubation (I.T.) of the tdp are discussed. Cyanide was found to be a major factor associated with severe toxic responses of the experimental rats.

  17. Polymer compositions and methods

    DOEpatents

    Allen, Scott D.; Willkomm, Wayne R.

    2016-09-27

    The present invention encompasses polyurethane compositions comprising aliphatic polycarbonate chains. In one aspect, the present invention encompasses polyurethane foams, thermoplastics and elastomers derived from aliphatic polycarbonate polyols and polyisocyanates wherein the polyol chains contain a primary repeating unit having a structure: ##STR00001## In another aspect, the invention provides articles comprising the inventive foam and elastomer compositions as well as methods of making such compositions.

  18. Removal of adhesive wound dressing and its effects on the stratum corneum of the skin: comparison of eight different adhesive wound dressings.

    PubMed

    Matsumura, Hajime; Imai, Ryutaro; Ahmatjan, Niyaz; Ida, Yukiko; Gondo, Masahide; Shibata, Dai; Wanatabe, Katsueki

    2014-02-01

    In recent years, adhesive wound dressings have been increasingly applied postoperatively because of their ease of use as they can be kept in place without having to cut and apply surgical tapes and they can cover a wound securely. However, if a wound dressing strongly adheres to the wound, a large amount of stratum corneum is removed from the newly formed epithelium or healthy periwound skin. Various types of adhesives are used on adhesive wound dressings and the extent of skin damage depends on how much an adhesive sticks to the wound or skin surface. We quantitatively determined and compared the amount of stratum corneum removed by eight different wound dressings including polyurethane foam using acrylic adhesive, silicone-based adhesive dressing, composite hydrocolloid and self-adhesive polyurethane foam in healthy volunteers. The results showed that wound dressings with silicone adhesive and self-adhesive polyurethane foam removed less stratum corneum, whereas composite hydrocolloid and polyurethane foam using acrylic adhesive removed more stratum corneum. © 2012 The Authors. International Wound Journal © 2012 Medicalhelplines.com Inc and John Wiley & Sons Ltd.

  19. [First experience of a polyurethane foam composition "Locus" use to stop intra-abdominal hemorrhage as a result of liver damage of V degree. (An experimental study)].

    PubMed

    Reva, V A; Litinskii, M A; Denisov, A V; Sokhranov, M V; Telitskii, S Yu; Samokhvalov, I M

    2015-04-01

    Today self-expanding polymers are considered as the most promising as means for intracavitary hemostasis in case of continuing bleeding after trauma. Testing of domestic open-cell polyurethane foam composition "Locus" was carried out on the developed experimental model simulating liver trauma of V degree. After damaging 6 experimental rabbits were injected intraperitoneally with 80 ml of the composition. 5 experimental rabbits were included into to control group (haemostatic agent was not given). Estimated blood loss was 111-124 ml. The two-hour survival rate didn't differ significantly: 3 animals survived in the experimental group; 2 animal survived in the control. Despite the 3-4-fold widening of the foam, due to open cells it absorbed 72.6 +/- 8.3 g of blood. Thus, open-cell polyurethane foam intraperitoneal administration of the composition didn't provide a temporary intra-abdominal hemostasis in liver. In order to enhance the hemostatic effect it requires changing the formulation of the polyurethane composition. For a more accurate assessment of the results it is neccessary to perform additional researches on larger animals.

  20. Evaluation of different methods for immobilization of Candida antarctica lipase B (CalB lipase) in polyurethane foam and its application in the production of geranyl propionate.

    PubMed

    Nicoletti, Gabrieli; Cipolatti, Eliane P; Valério, Alexsandra; Carbonera, NatáliaThaisa Gamba; Soares, Nicole Spillere; Theilacker, Eron; Ninow, Jorge L; de Oliveira, Débora

    2015-09-01

    With the aim of studying the best method for the interaction of polyurethane (PU) foam and Candida antarctica lipase B, different methods of CalB immobilization were studied: adsorption (PU-ADS), bond (using polyethyleneimine) (PU-PEI), ionic adsorption by PEI with cross-linking with glutaraldehyde (PU-PEI-GA) and entrapment (PU). The characterization of immobilized enzyme derivatives was performed by apparent density and Fourier transform infrared spectroscopy. The free enzyme and enzyme preparations were evaluated at different pH values and temperatures. The highest enzyme activity was obtained using the PU method (5.52 U/g). The methods that stood out to compare the stabilities and kinetic parameters were the PU and PU-ADS. Conversions of 83.5 and 95.9 % for PU and PU-ADS derivatives were obtained, in 24 h reaction, using citronella oil and propionic acid as substrates.

  1. Closure of oroantral communications using biodegradable polyurethane foam: a feasibility study.

    PubMed

    Visscher, Susan H; van Minnen, Baucke; Bos, Rudolf R M

    2010-02-01

    The aim of this study was to assess the feasibility of biodegradable polyurethane (PU) foam for closure of oroantral communications (OACs). Ten consecutive patients with OACs (existing <24 hours) were treated with PU foam. Standardized evaluations were performed at 2 weeks and 8 weeks after closure of the OAC. In 5 patients, the OACs were closed successfully without complications. Three patients developed sinusitis, which was conservatively managed with antibiotics in 2 cases. In 1 case the sinus was reopened for irrigation, after which a buccal flap procedure was performed. In 2 patients the OAC recurred and was surgically closed with a buccal flap after thorough irrigation. In this feasibility study, closure was achieved in 7 of the 10 patients without further surgical intervention. Complications of the procedure using PU foam may be related to the fit of the foam in the socket and the size of the perforation. In general, closure of OACs with biodegradable polyurethane foam is feasible and has the potential to spare a large number of patients with OACs a surgical procedure. Furthermore, in case the treatment with PU foam fails to close the OAC, the attending physician can always fall back on the standard surgical procedure. Copyright 2010 American Association of Oral and Maxillofacial Surgeons. Published by Elsevier Inc. All rights reserved.

  2. Experimental Polyurethane Foam Roof Systems - II.

    DTIC Science & Technology

    1983-01-01

    distribution unlimited. qt’, B 11 1 A F FN 1 5.6,-’ ,". I Rf- IE I0 Edthat, I.f "" Roofs, energy conservation, insulation, sprayed polyurethane foam...pcriod is presented, and thle energy savings realized by Oamning thle roof’ are prese nted. Libirary Card Naval Civil lFiginvee.ig I alora tor)i...the energy savings I reali/ed by foaming the roof are presented.I Unclassified rC~U~tTY CL ASSIrICATIO)N OF THISt PAGi-h WI-., . I -d CONTENTS Page

  3. Dynamic characterization of frequency response of shock mitigation of a polymethylene diisocyanate (PMDI) based rigid polyurethane foam

    DOE PAGES

    Song, Bo; Nelson, Kevin

    2015-09-01

    Kolsky compression bar experiments were conducted to characterize the shock mitigation response of a polymethylene diisocyanate (PMDI) based rigid polyurethane foam, abbreviated as PMDI foam in this study. The Kolsky bar experimental data was analyzed in the frequency domain with respect to impact energy dissipation and acceleration attenuation to perform a shock mitigation assessment on the foam material. The PMDI foam material exhibits excellent performance in both energy dissipation and acceleration attenuation, particularly for the impact frequency content over 1.5 kHz. This frequency (1.5 kHz) was observed to be independent of specimen thickness and impact speed, which may represent themore » characteristic shock mitigation frequency of the PMDI foam material under investigation. The shock mitigation characteristics of the PMDI foam material were insignificantly influenced by the specimen thickness. As a result, impact speed did have some effect.« less

  4. Dynamic characterization of frequency response of shock mitigation of a polymethylene diisocyanate (PMDI) based rigid polyurethane foam

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Song, Bo; Nelson, Kevin

    Kolsky compression bar experiments were conducted to characterize the shock mitigation response of a polymethylene diisocyanate (PMDI) based rigid polyurethane foam, abbreviated as PMDI foam in this study. The Kolsky bar experimental data was analyzed in the frequency domain with respect to impact energy dissipation and acceleration attenuation to perform a shock mitigation assessment on the foam material. The PMDI foam material exhibits excellent performance in both energy dissipation and acceleration attenuation, particularly for the impact frequency content over 1.5 kHz. This frequency (1.5 kHz) was observed to be independent of specimen thickness and impact speed, which may represent themore » characteristic shock mitigation frequency of the PMDI foam material under investigation. The shock mitigation characteristics of the PMDI foam material were insignificantly influenced by the specimen thickness. As a result, impact speed did have some effect.« less

  5. FAST TRACK COMMUNICATION: Mechanical, electrical and micro-structural properties of La0.6Sr0.4Co0.2Fe0.8O3 perovskite-based ceramic foams

    NASA Astrophysics Data System (ADS)

    Gupta, Ravindra K.; Kim, Eun Yi; Noh, Ho Sung; Whang, Chin Myung

    2008-02-01

    Mechanical, electrical and micro-structural properties of new electronic conducting ceramic foams are reported. Ceramic foams are prepared using the slurry of La0.6Sr0.4Co0.2Fe0.8O3 (LSCF) by the polymeric sponge method, which is followed by spray coating for increasing the number of coatings-sinterings on polyurethane foams of 30, 45 and 60 ppi (pores per linear inch). An increase in the number of coatings-sinterings and ppi improved the compressive strength, density and electrical conductivity by decreasing the porosity to ~76%, as also observed by the SEM study. The three-times coated-sintered ceramic foams (60 ppi) exhibited optimum values of compressive strength of ~1.79 MPa and relative density of ~0.24 at 25 °C and electrical conductivity of ~22 S cm-1 at 600 °C with an activation energy of ~0.22 eV indicating its suitability as a solid oxide fuel cell current collector. The experimental results are discussed in terms of the Gibson and Ashby theoretical model.

  6. 40 CFR 63.1301 - Standards for rebond foam production.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... National Emission Standards for Hazardous Air Pollutants for Flexible Polyurethane Foam Production § 63.1301 Standards for rebond foam production. Each owner or operator of a new or existing rebond foam... 40 Protection of Environment 11 2011-07-01 2011-07-01 false Standards for rebond foam production...

  7. 40 CFR 63.1301 - Standards for rebond foam production.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... National Emission Standards for Hazardous Air Pollutants for Flexible Polyurethane Foam Production § 63.1301 Standards for rebond foam production. Each owner or operator of a new or existing rebond foam... 40 Protection of Environment 12 2012-07-01 2011-07-01 true Standards for rebond foam production...

  8. 40 CFR 63.1301 - Standards for rebond foam production.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... National Emission Standards for Hazardous Air Pollutants for Flexible Polyurethane Foam Production § 63.1301 Standards for rebond foam production. Each owner or operator of a new or existing rebond foam... 40 Protection of Environment 11 2010-07-01 2010-07-01 true Standards for rebond foam production...

  9. Investigation of the dynamic stress–strain response of compressible polymeric foam using a non-parametric analysis

    DOE PAGES

    Koohbor, Behrad; Kidane, Addis; Lu, Wei -Yang; ...

    2016-01-25

    Dynamic stress–strain response of rigid closed-cell polymeric foams is investigated in this work by subjecting high toughness polyurethane foam specimens to direct impact with different projectile velocities and quantifying their deformation response with high speed stereo-photography together with 3D digital image correlation. The measured transient displacement field developed in the specimens during high stain rate loading is used to calculate the transient axial acceleration field throughout the specimen. A simple mathematical formulation based on conservation of mass is also proposed to determine the local change of density in the specimen during deformation. By obtaining the full-field acceleration and density distributions,more » the inertia stresses at each point in the specimen are determined through a non-parametric analysis and superimposed on the stress magnitudes measured at specimen ends to obtain the full-field stress distribution. Furthermore, the process outlined above overcomes a major challenge in high strain rate experiments with low impedance polymeric foam specimens, i.e. the delayed equilibrium conditions can be quantified.« less

  10. Technical characteristics of rigid sprayed PUR and PIR foams used in construction industry

    NASA Astrophysics Data System (ADS)

    Gravit, Marina; Kuleshin, Aleksey; Khametgalieva, Elina; Karakozova, Irina

    2017-10-01

    The article describes the distinctive properties of rigid polyurethane foam and polyisocyanurate (PUR and PIR). A brief review of the research was carried out on their modification with an objective to improve the thermal insulation properties and reducing the combustibility. A comparative analysis of the technical characteristics of rigid PUR and PIR foams of various manufacturers is presented. The problems of the state of the market for the production of polyurethane foam and polyisocyanurate in Russia have been marked. It is established that the further development of the fabrication technology of heat-insulating sprayed rigid PUR and PIR foams requires uniformity of technical characteristics of original components and finished products. Moreover, it requires the creation of unified information base for raw materials and auxiliary materials used in the production of PUR and PIR foam.

  11. 75 FR 38007 - Airworthiness Directives; The Boeing Company Model 747-100, 747-100B, 747-100B SUD, 747-200B, 747...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2010-07-01

    ... the environmental control system (ECS). This AD results from reports of duct assemblies in the ECS... assemblies in the ECS wrapped with BMS 8-39 polyurethane foam insulation, a material of which the fire... igniting the BMS 8-39 polyurethane foam insulation on the duct assemblies of the ECS, which could propagate...

  12. Water as foaming agent for open cell polyurethane structures.

    PubMed

    Haugen, H; Ried, V; Brunner, M; Will, J; Wintermantel, E

    2004-04-01

    The problem of moisture in polymer processing is known to any polymer engineer, as air bubbles may be formed. Hence granulates are generally dried prior to manufacturing. This study tried to develop a novel processing methods for scaffolds with controlled moisture content in thermoplastic polyurethane. The common foaming agents for polyurethane are organic solvents, whose residues remaining in the scaffold may be harmful to adherent cells, protein growth factors or nearby tissues. Water was used as a foaming agent and NaCl was used as porogens to achieve an open-cell structure. The polyether-polyurethane samples were processed in a heated press, and achieved a porosity of 64%. The pore size ranged between 50 and 500 microm. Human fibroblasts adhered and proliferate in the scaffold. A non-toxic production process was developed to manufacture a porous structure with a thermoplastic polyether-polyurethane. The process enables a mass-production of samples with adjustable pore size and porosity. In contrast to an existing method (solvent casting), the processing of the samples was not limited by its thickness. The process parameters, which attribute mostly to the pore building, were filling volume, temperature, NaCl-concentration and water-uptake rate.

  13. Reinforcement of osteosynthesis screws with brushite cement.

    PubMed

    Van Landuyt, P; Peter, B; Beluze, L; Lemaître, J

    1999-08-01

    The fixation of osteosynthesis screws remains a severe problem for fracture repair among osteoporotic patients. Polymethyl-methacrylate (PMMA) is routinely used to improve screw fixation, but this material has well-known drawbacks such as monomer toxicity, exothermic polymerization, and nonresorbability. Calcium phosphate cements have been developed for several years. Among these new bone substitution materials, brushite cements have the advantage of being injectable and resorbable. The aim of this study is to assess the reinforcement of osteosynthesis screws with brushite cement. Polyurethane foams, whose density is close to that of cancellous bone, were used as bone model. A hole was tapped in a foam sample, then brushite cement was injected. Trabecular osteosynthesis screws were inserted. After 24 h of aging in water, the stripping force was measured by a pull-out test. Screws (4.0 and 6.5 mm diameter) and two foam densities (0.14 and 0.28 g/cm3) were compared. Cements with varying solid/liquid ratios and xanthan contents were used in order to obtain the best screw reinforcement. During the pull-out test, the stripping force first increases to a maximum, then drops to a steady-state value until complete screw extraction. Both maximum force and plateau value increase drastically in the presence of cement. The highest stripping force is observed for 6.5-mm screws reinforced with cement in low-density foams. In this case, the stripping force is multiplied by 3.3 in the presence of cement. In a second experiment, cements with solid/liquid ratio ranging from 2.0 to 3.5 g/mL were used with 6.5-mm diameter screws. In some compositions, xanthan was added to improve injectability. The best results were obtained with 2.5 g/mL cement containing xanthan and with 3.0 g/mL cements without xanthan. A 0.9-kN maximal stripping force was observed with nonreinforced screws, while 1.9 kN was reached with reinforced screws. These first results are very promising regarding screw reinforcement with brushite cement. However, the polyurethane foam model presents noninterconnected porosity and physiological liquid was not modelized.

  14. Preparation and Sound Absorption Properties of a Barium Titanate/Nitrile Butadiene Rubber–Polyurethane Foam Composite with Multilayered Structure

    PubMed Central

    Jiang, Xueliang; Yang, Zhen; Wang, Zhijie; Zhang, Fuqing; You, Feng

    2018-01-01

    Barium titanate/nitrile butadiene rubber (BT/NBR) and polyurethane (PU) foam were combined to prepare a sound-absorbing material with an alternating multilayered structure. The effects of the cell size of PU foam and the alternating unit number on the sound absorption property of the material were investigated. The results show that the sound absorption efficiency at a low frequency increased when decreasing the cell size of PU foam layer. With the increasing of the alternating unit number, the material shows the sound absorption effect in a wider bandwidth of frequency. The BT/NBR-PU foam composites with alternating multilayered structure have an excellent sound absorption property at low frequency due to the organic combination of airflow resistivity, resonance absorption, and interface dissipation. PMID:29565321

  15. Preparation and Sound Absorption Properties of a Barium Titanate/Nitrile Butadiene Rubber-Polyurethane Foam Composite with Multilayered Structure.

    PubMed

    Jiang, Xueliang; Yang, Zhen; Wang, Zhijie; Zhang, Fuqing; You, Feng; Yao, Chu

    2018-03-22

    Barium titanate/nitrile butadiene rubber (BT/NBR) and polyurethane (PU) foam were combined to prepare a sound-absorbing material with an alternating multilayered structure. The effects of the cell size of PU foam and the alternating unit number on the sound absorption property of the material were investigated. The results show that the sound absorption efficiency at a low frequency increased when decreasing the cell size of PU foam layer. With the increasing of the alternating unit number, the material shows the sound absorption effect in a wider bandwidth of frequency. The BT/NBR-PU foam composites with alternating multilayered structure have an excellent sound absorption property at low frequency due to the organic combination of airflow resistivity, resonance absorption, and interface dissipation.

  16. Rigid palm oil-based polyurethane foam reinforced with diamine-modified montmorillonite nanoclay

    NASA Astrophysics Data System (ADS)

    Haziq Dzulkifli, Mohd; Yazid Yahya, Mohd; Majid, Rohah A.

    2017-05-01

    This paper presents work on organically-modified montmorillonite (MMT) nanoclay embedded in rigid palm oil-based polyurethane (PU) foam. MMT was modified with organic surfactant diamino propane (DAP). PU foam was fabricated in closed mold, and the amount of DAP-MMT was varied in each foam formulation. The obtained foam was tested for its microstructure and morphology. Appearance of peaks from infra-red spectra corresponding to N-H, C=O, and C-N confirms the formation of PU networks. Scanning electron microscopy (SEM) revealed fine, closed-cellular structure at low clay loading; increasing DAP-MMT content induced larger cell sizes with blowholes. X-ray diffraction (XRD) indicates fully-exfoliated clays at 1 wt. % and partial-exfoliation at 3 wt. % clay loading, suggesting clumping of clays as DAP-MMT content increased.

  17. Polyurethane Filler for Electroplating

    NASA Technical Reports Server (NTRS)

    Beasley, J. L.

    1984-01-01

    Polyurethane foam proves suitable as filler for slots in parts electroplated with copper or nickel. Polyurethane causes less contamination of plating bath and of cleaning and filtering tanks than wax fillers used previously. Direct cost of maintenance and indirect cost of reduced operating time during tank cleaning also reduced.

  18. Cryogenic line insulation made from prefabricated polyurethane shells

    NASA Technical Reports Server (NTRS)

    Lerma, G.

    1975-01-01

    Prefabricated polyurethane foam insulation is inexpensive and easily installed on cryogenic lines. Insulation sections are semicircular half shells. Pair of half shells is placed to surround cryogenic line. Cylindrically-shaped knit sock is pulled over insulation then covered with polyurethane resin to seal system.

  19. Thermal conductivity and combustion properties of wheat gluten foams.

    PubMed

    Blomfeldt, Thomas O J; Nilsson, Fritjof; Holgate, Tim; Xu, Jianxiao; Johansson, Eva; Hedenqvist, Mikael S

    2012-03-01

    Freeze-dried wheat gluten foams were evaluated with respect to their thermal and fire-retardant properties, which are important for insulation applications. The thermal properties were assessed by differential scanning calorimetry, the laser flash method and a hot plate method. The unplasticised foam showed a similar specific heat capacity, a lower thermal diffusivity and a slightly higher thermal conductivity than conventional rigid polystyrene and polyurethane insulation foams. Interestingly, the thermal conductivity was similar to that of closed cell polyethylene and glass-wool insulation materials. Cone calorimetry showed that, compared to a polyurethane foam, both unplasticised and glycerol-plasticised foams had a significantly longer time to ignition, a lower effective heat of combustion and a higher char content. Overall, the unplasticised foam showed better fire-proof properties than the plasticized foam. The UL 94 test revealed that the unplasticised foam did not drip (form droplets of low viscous material) and, although the burning times varied, self-extinguished after flame removal. To conclude both the insulation and fire-retardant properties were very promising for the wheat gluten foam. © 2012 American Chemical Society

  20. Ultra Low Density Shape Memory Polymer Foams With Tunable Physicochemical Properties for Treatment of intracranial Aneurysms

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Singhal, Pooja

    Shape memory polymers (SMPs) are a rapidly emerging class of smart materials that can be stored in a deformed temporary shape, and can actively return to their original shape upon application of an external stimulus such as heat, pH or light. This behavior is particularly advantageous for minimally invasive biomedical applications comprising embolic/regenerative scaffolds, as it enables a transcatheter delivery of the device to the target site. The focus of this work was to exploit this shape memory behavior of polyurethanes, and develop an efficient embolic SMP foam device for the treatment of intracranial aneurysms.In summary, this work reports amore » novel family of ultra low density polymer foams which can be delivered via a minimally invasive surgery to the aneurysm site, actuated in a controlled manner to efficiently embolize the aneurysm while promoting physiological fluid/blood flow through the reticulated/open porous structure, and eventually biodegrade leading to complete healing of the vasculature.« less

  1. DOE Office of Scientific and Technical Information (OSTI.GOV)

    Koohbor, Behrad; Kidane, Addis; Lu, Wei -Yang

    Dynamic stress–strain response of rigid closed-cell polymeric foams is investigated in this work by subjecting high toughness polyurethane foam specimens to direct impact with different projectile velocities and quantifying their deformation response with high speed stereo-photography together with 3D digital image correlation. The measured transient displacement field developed in the specimens during high stain rate loading is used to calculate the transient axial acceleration field throughout the specimen. A simple mathematical formulation based on conservation of mass is also proposed to determine the local change of density in the specimen during deformation. By obtaining the full-field acceleration and density distributions,more » the inertia stresses at each point in the specimen are determined through a non-parametric analysis and superimposed on the stress magnitudes measured at specimen ends to obtain the full-field stress distribution. Furthermore, the process outlined above overcomes a major challenge in high strain rate experiments with low impedance polymeric foam specimens, i.e. the delayed equilibrium conditions can be quantified.« less

  2. Effect of lignin derivatives in the bio-polyols from microwave liquefied bamboo on the properties of polyurethane foams

    Treesearch

    Jiulong Xie; Jinqiu Qi; Chung-Yun Hse; Todd F. Shupe

    2014-01-01

    Bamboo residues were subjected to a microwave-assisted liquefaction process for the production of crude bio-polyols (CBP). The fractionated bio-polyols (FBP) were obtained by the removal of lignin derivatives from the crude bio-polyols (CBP) using a simple method. Polyurethane (PU) foams were successfully prepared from both CBP and FBP. The object of this study was to...

  3. Rigid Polyurethane Foam (RPF) Technology for Countermine (SEA) Program - Phase 1

    DTIC Science & Technology

    1997-01-01

    Form ApprovedOMB No. 0704-0188 Public reporting burden for the collection of information is estimated to average 1 hour...05 MAY 1997 2. REPORT TYPE 3. DATES COVERED 00-00-1997 to 00-00-1997 4. TITLE AND SUBTITLE Rigid Polyurethane Foam (RPF) Technology for...unclassified b. ABSTRACT unclassified c. THIS PAGE unclassified Standard Form 298 (Rev. 8-98) Prescribed by ANSI Std Z39-18

  4. Preparation of linear hydroxy substituted polyphosphazenes. [flame retardant polyurethane foam

    NASA Technical Reports Server (NTRS)

    Paciorek, K. L.; Ito, T. I.; Kratzer, R. H.

    1978-01-01

    The synthesis of partially hydroxy-substituted phosphazene prepolymers amenable to processing into cellular, flexible polyurethane foams was investigated. Factors determined include (1) the environment of the hydroxyl group; (2) the ease of the hexachlorocyclotriphosphazene polymerization; (3) the nature of the nonreactive substituents; and (4) the mode of introduction of the hydroxyl entity. The specific approaches taken, the rationale of the selections made, and the results are discussed.

  5. Green engineering: Green composite material, biodiesel from waste coffee grounds, and polyurethane bio-foam

    NASA Astrophysics Data System (ADS)

    Cheng, Hsiang-Fu

    In this thesis we developed several ways of producing green materials and energy resources. First, we developed a method to fabricate natural fibers composites, with the purpose to develop green textile/woven composites that could potentially serve as an alternative to materials derived from non-renewable sources. Flax and hemp fabrics were chosen because of their lightweight and exceptional mechanical properties. To make these textile/woven composites withstand moist environments, a commercially available marine resin was utilized as a matrix. The tensile, three-point bending, and edgewise compression strengths of these green textile/woven composites were measured using ASTM protocols. Secondly, we developed a chemical procedure to obtain oil from waste coffee grounds; we did leaching and liquid extractions to get liquid oil from the solid coffee. This coffee oil was used to produce bio-diesel that could be used as a substitute for petroleum-based diesel. Finally, polyurethane Bio-foam formation utilized glycerol that is the by-product from the biodiesel synthesis. A chemical synthesis procedure from the literature was used as the reference system: a triol and isocynate are mixed to produce polyurethane foam. Moreover, we use a similar triol, a by-product from bio-diesel synthesis, to reproduce polyurethane foam.

  6. Randomized clinical trial to compare negative-pressure wound therapy approaches with low and high pressure, silicone-coated dressing, and polyurethane foam dressing.

    PubMed

    Lavery, Lawrence A; La Fontaine, Javier; Thakral, Gaurav; Kim, Paul J; Bhavan, Kavita; Davis, Kathryn E

    2014-03-01

    This study was designed to compare two approaches to negative-pressure wound therapy: 125-mmHg pressure with a polyurethane foam dressing and 75-mmHg pressure with a silicone-coated dressing. Forty patients with diabetic foot wounds, after incision and drainage or amputation for infection, were assigned randomly to negative-pressure wound therapy with 75-mmHg continuous pressure with a silicone-covered dressing (75-mmHg group) or 125-mmHg with a polyurethane foam dressing (125-mmHg group) for up to 4 weeks or until surgical closure. There was no difference in the proportion of wounds that were closed surgically (75-mmHg group, 50 percent; 125-mmHg group, 60 percent), wounds that demonstrated 50 percent wound area reduction (75-mmHg group, 65 percent; 125-mmHg group, 80 percent), or wounds that demonstrated 50 percent wound volume reduction after 4 weeks of therapy (75-mmHg group, 95 percent; 125-mmHg group, 90 percent). The authors' results suggest that there was no difference in outcomes in wounds treated with low pressure (75 mmHg) with a silicone-coated interface and high pressure (125 mmHg) with a polyurethane foam interface. Therapeutic, II.

  7. 40 CFR 82.62 - Definitions.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... distributes that product in interstate commerce for export from the United States. Foam Insulation Product, when used to describe a product containing or consisting of plastic foam, means a product containing or consisting of the following types of foam: (1) Closed cell rigid polyurethane foam; (2) Closed cell rigid...

  8. 40 CFR 82.62 - Definitions.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... distributes that product in interstate commerce for export from the United States. Foam Insulation Product, when used to describe a product containing or consisting of plastic foam, means a product containing or consisting of the following types of foam: (1) Closed cell rigid polyurethane foam; (2) Closed cell rigid...

  9. 40 CFR 82.62 - Definitions.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... distributes that product in interstate commerce for export from the United States. Foam Insulation Product, when used to describe a product containing or consisting of plastic foam, means a product containing or consisting of the following types of foam: (1) Closed cell rigid polyurethane foam; (2) Closed cell rigid...

  10. 40 CFR 82.62 - Definitions.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... distributes that product in interstate commerce for export from the United States. Foam Insulation Product, when used to describe a product containing or consisting of plastic foam, means a product containing or consisting of the following types of foam: (1) Closed cell rigid polyurethane foam; (2) Closed cell rigid...

  11. Multiple-Nozzle Spray Head Applies Foam Insulation

    NASA Technical Reports Server (NTRS)

    Walls, Joe T.

    1993-01-01

    Spray head equipped with four-nozzle turret mixes two reactive components of polyurethane and polyisocyanurate foam insulating material and sprays reacting mixture onto surface to be insulated. If nozzle in use becomes clogged, fresh one automatically rotated into position, with minimal interruption of spraying process. Incorporates features recirculating and controlling pressures of reactive components to maintain quality of foam by ensuring proper blend at outset. Also used to spray protective coats on or in ships, aircraft, and pipelines. Sprays such reactive adhesives as epoxy/polyurethane mixtures. Components of spray contain solid-particle fillers for strength, fire retardance, toughness, resistance to abrasion, or radar absorption.

  12. Quasi-static axial crushes on woven jute/polyester AA6063T52 composite tubes

    NASA Astrophysics Data System (ADS)

    Othman, A.; Ismail, AE

    2018-04-01

    Quasi-static axial loading have been studied in this paper to determine the behaviour of jute/polyester wrapped on aluminium alloy 6063T52. The filler material also was include into crush box specimen, which is polyurethane (PU) and polystyrene (PE) rigid foam at ranging 40 and 45 kg/m3 densities. All specimen profile was fabricated using hand layup techniques and the length of each specimen were fixed at 100 mm as well as diameter and width of the tube at 50.8 mm. The two types of tubular cross-section were studied of round and square thin-walled profiles and the angle of fibre at 450 were analysed for four layers. Thin walled of aluminium was 1.9 mm and end frontal of each specimen of composite were chamfered at 450 to prevent catastrophic failure mode. The specific absorbed energy (SEA) and crush force efficiency (CFE) were analyses for each specimen to see the behaviour on jute/polyester wrapped on metallic structure can give influence the energy management for automotive application. Result show that the four layers’ jute/polyester with filler material show significant value in term of specific absorbed energy compared empty and polyurethane profiles higher 26.66% for empty and 15.19% compared to polyurethane profiles. It has been found that the thin walled square profile of the jute/polyester tubes with polystyrene foam-filled is found higher respectively 27.42% to 13.13% than empty and polyurethane (PU) foam tubes. An introduce filler material onto thin walled composite profiles gave major advantage increases the mean axial load of 31.87% from 32.94 kN to 48.35 kN from empty to polystyrene thin walled round jute/polyester profiles and 31.7% from 23.11 KN to 33.84 kN from empty to polystyrene thin walled square jute/polyester profiles. Failure mechanisms of the axially loaded composite tubes were also observed and discussed.

  13. Comparison of solvent/derivatization agent systems for determination of extractable toluene diisocyanate from flexible polyurethane foam.

    PubMed

    Vangronsveld, Erik; Berckmans, Steven; Spence, Mark

    2013-06-01

    Flexible polyurethane foam (FPF) is produced from the reaction of toluene diisocyanate (TDI) and polyols. Limited and conflicting results exist in the literature concerning the presence of unreacted TDI remaining in FPF as determined by various solvent extraction and analysis techniques. This study reports investigations into the effect of several solvent/derivatization agent combinations on extractable TDI results and suggests a preferred method. The suggested preferred method employs a syringe-based multiple extraction of foam samples with a toluene solution of 1-(2-methoxyphenyl)-piperazine. Extracts are analyzed by liquid chromatography using an ion trap mass spectrometry detection technique. Detection limits of the method are ~10ng TDI g(-1) foam (10 ppb, w/w) for each TDI isomer (i.e. 2,4-TDI and 2,6-TDI). The method was evaluated by a three-laboratory interlaboratory comparison using two representative foam samples. The total extractable TDI results found by the three labs for the two foams were in good agreement (relative standard deviation of the mean of 30-40%). The method has utility as a basis for comparing FPFs, but the interpretation of extractable TDI results using any solvent as the true value for 'free' or 'unreacted' TDI in the foam is problematic, as demonstrated by the difference in the extracted TDI results from the different extraction systems studied. Further, a consideration of polyurethane foam chemistry raises the possibility that extractable TDI may result from decomposition of parts of the foam structure (e.g. dimers, biurets, and allophanates) by the extraction system.

  14. 40 CFR 63.1301 - Standards for rebond foam production.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... (CONTINUED) National Emission Standards for Hazardous Air Pollutants for Flexible Polyurethane Foam Production § 63.1301 Standards for rebond foam production. Each owner or operator of a new or existing rebond... 40 Protection of Environment 12 2014-07-01 2014-07-01 false Standards for rebond foam production...

  15. 40 CFR 63.1301 - Standards for rebond foam production.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... (CONTINUED) National Emission Standards for Hazardous Air Pollutants for Flexible Polyurethane Foam Production § 63.1301 Standards for rebond foam production. Each owner or operator of a new or existing rebond... 40 Protection of Environment 12 2013-07-01 2013-07-01 false Standards for rebond foam production...

  16. Stress wave propagation and mitigation in two polymeric foams

    NASA Astrophysics Data System (ADS)

    Pradel, Pierre; Malaise, Frederic; Cadilhon, Baptiste; Quessada, Jean-Hugues; de Resseguier, Thibaut; Delhomme, Catherine; Le Blanc, Gael

    2017-06-01

    Polymeric foams are widely used in industry for thermal insulation or shock mitigation. This paper investigates the ability of a syntactic epoxy foam and an expanded polyurethane foam to mitigate intense (several GPa) and short duration (<10-6 s) stress pulses. Plate impact and electron beam irradiation experiments have been conducted to study the dynamic mechanical responses of both foams. Interferometer Doppler Laser method is used to record the target rear surface velocity. A two-wave structure associated with the propagation of an elastic precursor followed by the compaction of the pores has been observed. The compaction stress level deduced from the velocity measurement is a good indicator of mitigation capability of the foams. Quasi-static tests and dynamic soft recovery experiments have also been performed to determine the compaction mechanisms. In the polyurethane foam, the pores are closed by elastic buckling of the matrix and damage of the structure. In the epoxy foam, the compaction is due to the crushing of glass microspheres. Two porous material models successfully represent the macroscopic response of these polymeric foams.

  17. Preparation of polyurethane foams using liquefied oil palm mesocarp fibre (OPMF) and renewable monomer from waste cooking oil

    NASA Astrophysics Data System (ADS)

    Kormin, Shaharuddin; Rus, Anika Zafiah M.; Azahari, M. Shafiq M.

    2017-09-01

    The aim of this research is the production of polyurethane (PU) foams with biopolyols from liquefied oil palm mesocarp fibre (OPMF) and renewable monomer. Liquefaction of OPMF was studied using polyhydric alcohol (PA) which is PEG-400 as liquefaction solvents in conventional glass flask. In the second part of this paper was obtained the PU foams which presented good results when compared with commercial foams and include polyols from of fossil fuels. PU foams were prepared by mixing liquefied OPMF biopolyol, renewable monomer from waste cooking, additives and methylene diphenyl diisocyanate (MDI). Water was used as an environmental friendly blowing agent. The factors that influence the cell structure of foams (i.e., catalyst, surfactant, dosage of blowing agent, and mass ratio of biopolyol to renewable monomer were studied. The synthesized PU foams were characterized by FTIR and SEM. The formulation of the PU foams should be improved, but the results show that is possible the use biopolyols and renewable monomer to produce industrial foams with lower cost.

  18. Foam-Mixing-And-Dispensing Machine

    NASA Technical Reports Server (NTRS)

    Chong, Keith Y.; Toombs, Gordon R.; Jackson, Richard J.

    1996-01-01

    Time-and-money-saving machine produces consistent, homogeneously mixed foam, enhancing production efficiency. Automatically mixes and dispenses polyurethane foam in quantities specified by weight. Consists of cart-mounted, air-driven proportioning unit; air-activated mechanical mixing gun; programmable timer/counter, and controller.

  19. Geometric modeling of Plateau borders using the orthographic projection method for closed cell rigid polyurethane foam thermal conductivity prediction

    NASA Astrophysics Data System (ADS)

    Xu, Jie; Wu, Tao; Peng, Chuang; Adegbite, Stephen

    2017-09-01

    The geometric Plateau border model for closed cell polyurethane foam was developed based on volume integrations of approximated 3D four-cusp hypocycloid structure. The tetrahedral structure of convex struts was orthogonally projected into 2D three-cusp deltoid with three central cylinders. The idealized single unit strut was modeled by superposition. The volume of each component was calculated by geometric analyses. The strut solid fraction f s and foam porosity coefficient δ were calculated based on representative elementary volume of Kelvin and Weaire-Phelan structures. The specific surface area Sv derived respectively from packing structures and deltoid approximation model were put into contrast against strut dimensional ratio ɛ. The characteristic foam parameters obtained from this semi-empirical model were further employed to predict foam thermal conductivity.

  20. Electrostatic Safety with Explosion Suppressant Foams.

    DTIC Science & Technology

    1983-03-01

    the foam, and (2) sorption of alkylphenol type substances, present as oxidation inhibitors in the fuel, by the foam. It had been previously reported... alkylphenol type substances. The use of antistatic ingredients in the reticulated polyurethane foam was suggested as a means of minimizing static...foam with JP-4 are: o Removal of diethylhexyl phthalate from the foam. o Sorption of alkylphenol type compounds by the foam. Tne latter of these two

  1. Comparison of mechanical behavior between implant-simulated bone tissue and implant-jaw bone tissue interfaces based on Pull Out testing

    NASA Astrophysics Data System (ADS)

    Lopez, C.; Muñoz, J. C.; Pinillos, J. C.

    2013-11-01

    The main purpose of this research was to achieve a better understanding of the relationship within the mechanical properties of human cadaver jaw bone with kind D2 density regarding a substitute polymer to simulate bone tissue, proposed by the ASTM, to evaluate orthopedic implants. However, despite the existence of several densities of foams and his mechanical characterization has been classified into different degrees of tissue densities to simulate cancellous and cortical bone, the value of the densities are different contrasted with the densities of bone tissue, making difficult to establish direct relationship about mechanical behavior between the polymer and the bone material, and therefore no clear criteria known for choosing the polymeric foam which describes the mechanical behavior of tissue for a specific or particular study. To understand such behavior from bone tissue regarding the polymer samples, on this research was a dental implant inserted into the samples, and subjected to destructive Pull Out test according to ASTM F543The Pull Out strength was compared between implant-jawbone and implant-rigid polyurethane foam interfaces. Thus, the test pieces with mechanical behavior similar to bone tissue, enabling an approximation to choose degree appropriate of polymer to replace the bone tissue in future trials biomechanical.

  2. 40 CFR 463.1 - Applicability.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... development laboratories. (f) Chemical and thermal reticulation processes for polyurethane foam are not... or form the reticulated foam are subject, however, to this regulation if they discharge process water...

  3. Low density biodegradable shape memory polyurethane foams for embolic biomedical applications

    PubMed Central

    Singhal, Pooja; Small, Ward; Cosgriff-Hernandez, Elizabeth; Maitland, Duncan J; Wilson, Thomas S

    2014-01-01

    Low density shape memory polymer foams hold significant interest in the biomaterials community for their potential use in minimally invasive embolic biomedical applications. The unique shape memory behavior of these foams allows them to be compressed to a miniaturized form, which can be delivered to an anatomical site via a transcatheter process, and thereafter actuated to embolize the desired area. Previous work in this field has described the use of a highly covalently crosslinked polymer structure for maintaining excellent mechanical and shape memory properties at the application-specific ultra low densities. This work is aimed at further expanding the utility of these biomaterials, as implantable low density shape memory polymer foams, by introducing controlled biodegradability. A highly covalently crosslinked network structure was maintained by use of low molecular weight, symmetrical and polyfunctional hydroxyl monomers such as Polycaprolactone triol (PCL-t, Mn 900 g), N,N,N0,N0-Tetrakis (hydroxypropyl) ethylenediamine (HPED), and Tris (2-hydroxyethyl) amine (TEA). Control over the degradation rate of the materials was achieved by changing the concentration of the degradable PCL-t monomer, and by varying the material hydrophobicity. These porous SMP materials exhibit a uniform cell morphology and excellent shape recovery, along with controllable actuation temperature and degradation rate. We believe that they form a new class of low density biodegradable SMP scaffolds that can potentially be used as “smart” non-permanent implants in multiple minimally invasive biomedical applications. PMID:24090987

  4. Metallized polymeric foam material

    NASA Technical Reports Server (NTRS)

    Birnbaum, B. A.; Bilow, N.

    1974-01-01

    Open-celled polyurethane foams can be coated uniformly with thin film of metal by vapor deposition of aluminum or by sensitization of foam followed by electroless deposition of nickel or copper. Foam can be further processed to increase thickness of metal overcoat to impart rigidity or to provide inert surface with only modest increase in weight.

  5. Polyurethane foams based on crude glycerol-derived biopolyols: One-pot preparation of biopolyols with branched fatty acid ester chains and its effects on foam formation and properties

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Li, Cong; Luo, Xiaolan; Li, Tao

    2014-01-01

    Environmentally friendly biopolyols have been produced with crude glycerol as the sole feedstock using a one-pot thermochemical conversion process without the addition of extra catalysts and reagents. Structural features of these biopolyols were characterized by rheology analysis. Rigid polyurethane (PU) foams were obtained from these crude glycerol-based biopolyols and the foaming mechanism was explored. Investigations revealed that partial carbonyl groups hydrogen-bonded with NeH were replaced by aromatic rings after the introduction of branched fatty acid ester chains in the “urea rich” phase, and that distinct microphases had formed in the foams. Studies showed that branched fatty acid ester chains inmore » the biopolyols played an important role in reducing the degree of microphase separation and stabilizing bubbles during foaming processes. PU foams with thermal conductivity comparable to commercial products made from petroleum-based polyols were obtained. These studies show the potential for development of PU foams based on crude glycerol, a renewable resource.« less

  6. Rigid polyurethane foam as an efficient material for shock wave attenuation

    NASA Astrophysics Data System (ADS)

    Komissarov, P. V.; Borisov, A. A.; Sokolov, G. N.; Lavrov, V. V.

    2016-09-01

    A new method for reducing parameters of blast waves generated by explosions of HE charges on ground is presented. Most of the traditional techniques reduce the wave parameters at a certain distance from the charge, i.e. as a matter of fact the damping device interacts with a completely formed shock wave. The proposed approach is to use rigid polyurethane foam coating immediately the explosive charge. A distributed structure of such a foam block that provides most efficient shock wave attenuation is suggested. Results of experimental shock wave investigations recorded in tests in which HE charges have been exploded with damping devices and without it are compared.

  7. Influence of Orientation and Radiative Heat Transfer on Aluminum Foams in Buoyancy-Induced Convection.

    PubMed

    Billiet, Marijn; De Schampheleire, Sven; Huisseune, Henk; De Paepe, Michel

    2015-10-09

    Two differently-produced open-cell aluminum foams were compared to a commercially available finned heat sink. Further, an aluminum plate and block were tested as a reference. All heat sinks have the same base plate dimensions of four by six inches. The first foam was made by investment casting of a polyurethane preform and has a porosity of 0.946 and a pore density of 10 pores per linear inch. The second foam is manufactured by casting over a solvable core and has a porosity of 0.85 and a pore density of 2.5 pores per linear inch. The effects of orientation and radiative heat transfer are experimentally investigated. The heat sinks are tested in a vertical and horizontal orientation. The effect of radiative heat transfer is investigated by comparing a painted/anodized heat sink with an untreated one. The heat flux through the heat sink for a certain temperature difference between the environment and the heat sink's base plate is used as the performance indicator. For temperature differences larger than 30 °C, the finned heat sink outperforms the in-house-made aluminum foam heat sink on average by 17%. Furthermore, the in-house-made aluminum foam dissipates on average 12% less heat than the other aluminum foam for a temperature difference larger than 40 °C. By painting/anodizing the heat sinks, the heat transfer rate increased on average by 10% to 50%. Finally, the thermal performance of the horizontal in-house-made aluminum foam heat sink is up to 18% larger than the one of the vertical aluminum foam heat sink.

  8. Back to the future: a 15-year experience with polyurethane foam-covered breast implants using the partial-subfascial technique.

    PubMed

    de la Peña-Salcedo, Jose Abel; Soto-Miranda, Miguel Angel; Lopez-Salguero, Jose Fernando

    2012-04-01

    Implants with a polyurethane foam cover have been used by plastic surgeons since Ashley described them in 1970. Overwhelming evidence confirms the benefits of these implants, especially the extremely low incidence of capsular contracture (grades 3 and 4, Baker classification). On the other hand, except for a transient and self-limited rash, there is no evidence that polyurethane implants present more complications than texturized or smooth gel implants. Due to concerns of polyurethane-induced cancer, these implants were withdrawn in United States after approximately 110,000 American women had received them. This fact, together with the probability that these implants will be reintroduced in the United States, suggests that continued monitoring of their long-term safety and effectiveness is mandatory. A retrospective study analyzed the outcomes of 996 implants inserted during a period of 15 years. The incidence of early and late complications was analyzed as well as the aesthetic outcome. The complications evaluated included hematoma (0.6%), infection (0.4%), seroma (0.8%), rash (4.3%), wound dehiscence (0%), capsular contracture (0.4%), implant malposition (0.8%), need for revisional surgery (1.2%), implant rupture (0.7%), rippling (1.8%), and polyurethane-related cancer (0%). Regarding the aesthetic outcome, 95% of the patients expressed satisfaction with their final result. The polyurethane foam-covered implants have been proven safe for use in breast surgery. They provide the lowest rate of capsular contracture (0.4% in the current study) and excellent aesthetic results.

  9. Halogenated flame-retardant concentrations in settled dust, respirable and inhalable particulates and polyurethane foam at gymnastic training facilities and residences.

    PubMed

    La Guardia, Mark J; Hale, Robert C

    2015-06-01

    Halogenated flame-retardants (FRs) are used in a wide array of polymer-containing products. Animal studies and structure-activity modeling exercises suggest that FR exposure may result in detrimental toxicological effects. Workers with extended contact with such polymers (e.g., electronic dismantlers, carpet installers and aircraft personnel) have previously been observed to exhibit elevated body burdens of FRs, e.g., polybrominated diphenyl ethers (PBDEs). Recently, elevated PBDE blood levels were also reported in a non-occupational exposure group, gymnasts. These levels were hypothesized to be related to the large volumes of FR-treated polyurethane foam in gymnastics facilities. To further our understanding of workers' potential exposure, we analyzed FR concentrations in indoor dust and size-fractionated air particulates (respirable (<4 μm) and inhalable (>4 μm)) from gymnastic studios. Values were compared to samples from the homes of coaches employed at these facilities. Polyurethane foam blocks (i.e., pit foam) were also analyzed to characterize potential FR sources. FRs examined included those used to flame-retard polyurethane foam: 8 PBDE congeners, two brominated components of Firemaster 550 (2-ethylhexyl 2, 3, 4, 5-tetrabromobenzoate (TBB) and bis(2-ethylhexyl) 3, 4, 5, 6-tetrabromophthalate (TBPH)) and three chlorinated organophosphates (tris(2-chloroethyl) phosphate (TCEP), tris(1-chloro-2-propyl) phosphate (TCPP) and tris(1,3-dichloro-2-propyl) phosphate (TDCPP)). Several additional FRs not used in polyurethane were also evaluated. These have also been detected in indoor dust and air and may also lead to adverse health effects. These include: BDE-183 and its replacement product (1, 2-bis(2, 4, 6-tribromophenoxy) ethane (BTBPE), two congeners of the deca-BDE formulation (BDE-206, -209) and their replacement decabromodiphenyl ethane (DBDPE) and hexabromocyclododecane (α-, β-, γ-HBCD), and tetrabromobisphenol-A (TBBPA)). Pit foam contained multiple FRs at cumulative concentrations of 12,100 to 25,800 μg g(-1), or 1.2% to 2.6% by weight. TBB and TBPH were the most abundant FRs detected, followed by TDCPP and several PBDEs. The mean total FR burden detected at the gyms was 8.6-fold higher (574 μg g(-1)) than that observed in the house dust samples (66.8 μg g(-1)). However, the polyurethane additives TBB and TDCPP were the only FRs that exhibited significantly greater levels (P<0.05) in gym than house dust. Mean levels of five FRs (BDE-99, -100, -153, -209 and TDCPP) were also higher in respirable particulates from the gyms than the homes and four FRs (BDE-47, TBB, TBPH and DBDPE) were higher at the homes than the gyms; these differences were not significant (P>0.05). Several additional FRs were detected in inhalable particulates; mean levels of BDE-66, -206 and TCPP were higher in the homes and BDE-47, -85, -99, -100, -153, -209, TBB, TBPH, and TDCPP were higher at the gyms. But, only the polyurethane additives i.e., BDE-100, TBB and TDCPP were significantly greater (P<0.05) in inhalable particulates from the gyms than at the homes. In conclusion, polyurethane foam collected from gymnastic studios exhibited a variety of FR compositional signatures; likely reflective of changes in FR usage over time and by different manufacturers. FR concentrations and compositional signatures also differed between settled dust, respirable and inhalable particulates between the gyms and homes. Concentrations of FRs used in polyurethane foam were higher in gym air and dust compared to homes, particularly TBB and TDCPP - which were also the primary FRs detected in the pit foam samples. Although these results should be interpreted with caution, as the sample size was small, these findings do suggest that FR concentrations observed in dust and air particulates from the gymnastic studios are further evidence that individuals frequenting these environments are at greater risk for exposure to these polymer additives. Copyright © 2015 Elsevier Ltd. All rights reserved.

  10. The effects of composition and sintering temperature on the silica foam fabricated by slurry method

    NASA Astrophysics Data System (ADS)

    Baharom, Syazwani; Ahmad, Sufizar; Taib, Hariati; Muda, Rizamarhaiza

    2016-07-01

    Reticulated ceramic or open pore ceramic foam is a well-known material which exhibits extremely high porosities, with a significant degree of interconnectivity that makes them desirable in a wide range of applications. There were broad types of ceramic foam fabrication method such as polymeric sponge method, direct foaming, and starch consolidation. In this study, the slurry method has been chosen to fabricate Silica (SiO2) foam. In this process, Polyurethane (PU) foam template was dipped into ceramic slurry and followed by drying and sintering to obtain foam which contains porosity in the range of 50% to 70%. The compositions of SiO2 were varied starting from 55 wt.%, 60 wt.%, 65 wt.% and 70 wt.%. The samples of SiO2 that have been dipped and dried were sintered at 900°C, 1000°C, 1100°C, and 1250°C. The sintered SiO2 ceramic foam samples were characterized to observe their morphology, and physical properties. Thus, the microstructure of the SiO2 ceramic foams samples was examined by Scanning Electron Microscopy (SEM), and Electron Dispersive Spectroscopy (EDS). Meanwhile, the physical properties of the SiO2 ceramic foam samples such as the total porosity (%) and bulk density were determined using Archimedes method. It was found that the density of ceramic foam produced was in the range of 0.25 g/cm3 up to 0.75 g/cm3, whereas the level of porosity percentage was in the range of 61.81% to 82.18% with the size of open pore or window cells were in between 141 µm up to 626 µm.

  11. The effects of composition and sintering temperature on the silica foam fabricated by slurry method

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Baharom, Syazwani, E-mail: hd140001@siswa.uthm.edu.my; Ahmad, Sufizar, E-mail: sufizar@uthm.edu.my; Taib, Hariati, E-mail: hariati@uthm.edu.my

    Reticulated ceramic or open pore ceramic foam is a well-known material which exhibits extremely high porosities, with a significant degree of interconnectivity that makes them desirable in a wide range of applications. There were broad types of ceramic foam fabrication method such as polymeric sponge method, direct foaming, and starch consolidation. In this study, the slurry method has been chosen to fabricate Silica (SiO{sub 2}) foam. In this process, Polyurethane (PU) foam template was dipped into ceramic slurry and followed by drying and sintering to obtain foam which contains porosity in the range of 50% to 70%. The compositions ofmore » SiO{sub 2} were varied starting from 55 wt.%, 60 wt.%, 65 wt.% and 70 wt.%. The samples of SiO{sub 2} that have been dipped and dried were sintered at 900°C, 1000°C, 1100°C, and 1250°C. The sintered SiO{sub 2} ceramic foam samples were characterized to observe their morphology, and physical properties. Thus, the microstructure of the SiO{sub 2} ceramic foams samples was examined by Scanning Electron Microscopy (SEM), and Electron Dispersive Spectroscopy (EDS). Meanwhile, the physical properties of the SiO{sub 2} ceramic foam samples such as the total porosity (%) and bulk density were determined using Archimedes method. It was found that the density of ceramic foam produced was in the range of 0.25 g/cm{sup 3} up to 0.75 g/cm{sup 3}, whereas the level of porosity percentage was in the range of 61.81% to 82.18% with the size of open pore or window cells were in between 141 µm up to 626 µm.« less

  12. High temperature electrical conductivity of rigid polyurethane foam

    NASA Astrophysics Data System (ADS)

    Johnson, R. T., Jr.

    1984-03-01

    The temperature dependence of the electrical conductivity of three rigid polyurethane foams prepared using different formulations was measured to approx. 320 C. The materials exhibit similar conductivity characteristics, showing a pronounced increase in conductivity with increasing temperature. The insulating characteristics to approx. 200 C are better than that for phenolic materials (glass fabric reinforced), and are similar to those for silicone materials (glass microsphere reinforced). At higher temperatures (500 to 600 C), the phenolics and silicones are better insulators.

  13. Three-Dimensional Scale-Model Tank Experiment of the Hudson Canyon Region

    DTIC Science & Technology

    2014-09-30

    coefficient at a water/ polyurethane foam interface,” J. Acoust. Soc. Am. 134, EL271–EL275 (2013). PUBLICATIONS Peer-reviewed papers J. D. Sagers...Sagers, M. R. Haberman, and P. S. Wilson, “Ultrasonic measurements of the reflection coefficient at a water/ polyurethane foam interface,” J. Acoust...completed apparatus installed in the indoor tank room at ARL:UT is shown in Fig. 2(b). The major components of the apparatus include the rigid

  14. Nitrogen removal in moving bed sequencing batch reactor using polyurethane foam cubes of various sizes as carrier materials.

    PubMed

    Lim, Jun-Wei; Seng, Chye-Eng; Lim, Poh-Eng; Ng, Si-Ling; Sujari, Amat-Ngilmi Ahmad

    2011-11-01

    The performance of moving bed sequencing batch reactors (MBSBRs) added with 8 % (v/v) of polyurethane (PU) foam cubes as carrier media in nitrogen removal was investigated in treating low COD/N wastewater. The results indicate that MBSBR with 8-mL cubes achieved the highest total nitrogen (TN) removal efficiency of 37% during the aeration period, followed by 31%, 24% and 19 % for MBSBRs with 27-, 64- and 125-mL cubes, respectively. The increased TN removal in MBSBRs was mainly due to simultaneous nitrification and denitrification (SND) process which was verified by batch studies. The relatively lower TN removal in MBSBR with larger PU foam cubes was attributed to the observation that larger PU foam cubes were not fully attached by biomass. Higher concentrations of 8-mL PU foam cubes in batch reactors yielded higher TN removal. Copyright © 2011 Elsevier Ltd. All rights reserved.

  15. Fire and ecotoxicological aspects of polyurethane rigid foam.

    PubMed

    Wittbecker, F W; Giersig, M

    2001-01-01

    The main characteristics of fire effluents from polyurethane (PUR) foams are comparable to those from natural materials like wood, cork, or wool. This similarity has been demonstrated by comparative data from analytical and toxicological studies. It is therefore presumed that effluents of these materials present similar hazards to human beings and the environment. In almost all fires, dioxins can be found in the smoke and residues. In fires involving PURs, relevant quantities of halogenated dioxins or furans are not to be expected; this has been confirmed by investigations under controlled laboratory conditions. The insulation properties of rigid PUR foam contribute significantly to environmental protection and the conservation of resources. A number of methods for reusing and recycling PUR rigid foam waste have been developed and realized in practise. The possibilities range from reusing the material itself, generating liquid raw materials, and thermal recycling, even for (H)CFC-containing PUR rigid foams, by cocombustion in suitable plants.

  16. Durability of foam insulation for LH2 fuel tanks of future subsonic transports

    NASA Technical Reports Server (NTRS)

    Sharpe, E. L.; Helenbrook, R. G.

    1978-01-01

    In connection with the potential short-supply of petroleum based fuels, NASA has initiated investigations concerning the feasibility of aircraft using as fuel hydrogen which is to be stored in liquid form. One of the problems to be solved for an operation of such aircraft is related to the possibility of a suitable storage of the liquid hydrogen. A description is presented of an experimental study regarding the suitability of commercially available organic foams as cryogenic insulation for liquid hydrogen tanks under extensive thermal cycling typical of subsonic airline type operation. Fourteen commercially available organic foam insulations were tested. The thermal performance of all insulations was found to deteriorate with increased simulated flight cycles. Two unreinforced polyurethane foams survived over 4200 thermal cycles (representative of approximately 15 years of airline service) without evidence of structural deterioration. The polyurethane foam insulations also exhibited excellent thermal performance.

  17. Optimization of low frequency sound absorption by cell size control and multiscale poroacoustics modeling

    NASA Astrophysics Data System (ADS)

    Park, Ju Hyuk; Yang, Sei Hyun; Lee, Hyeong Rae; Yu, Cheng Bin; Pak, Seong Yeol; Oh, Chi Sung; Kang, Yeon June; Youn, Jae Ryoun

    2017-06-01

    Sound absorption of a polyurethane (PU) foam was predicted for various geometries to fabricate the optimum microstructure of a sound absorbing foam. Multiscale numerical analysis for sound absorption was carried out by solving flow problems in representative unit cell (RUC) and the pressure acoustics equation using Johnson-Champoux-Allard (JCA) model. From the numerical analysis, theoretical optimum cell diameter for low frequency sound absorption was evaluated in the vicinity of 400 μm under the condition of 2 cm-80 K (thickness of 2 cm and density of 80 kg/m3) foam. An ultrasonic foaming method was employed to modulate microcellular structure of PU foam. Mechanical activation was only employed to manipulate the internal structure of PU foam without any other treatment. A mean cell diameter of PU foam was gradually decreased with increase in the amplitude of ultrasonic waves. It was empirically found that the reduction of mean cell diameter induced by the ultrasonic wave enhances acoustic damping efficiency in low frequency ranges. Moreover, further analyses were performed with several acoustic evaluation factors; root mean square (RMS) values, noise reduction coefficients (NRC), and 1/3 octave band spectrograms.

  18. Stabilizing nanocellulose-nonionic surfactant composite foams by delayed Ca-induced gelation.

    PubMed

    Gordeyeva, Korneliya S; Fall, Andreas B; Hall, Stephen; Wicklein, Bernd; Bergström, Lennart

    2016-06-15

    Aggregation of dispersed rod-like particles like nanocellulose can improve the strength and rigidity of percolated networks but may also have a detrimental effect on the foamability. However, it should be possible to improve the strength of nanocellulose foams by multivalent ion-induced aggregation if the aggregation occurs after the foam has been formed. Lightweight and highly porous foams based on TEMPO-mediated oxidized cellulose nanofibrils (CNF) were formulated with the addition of a non-ionic surfactant, pluronic P123, and CaCO3 nanoparticles. Foam volume measurements show that addition of the non-ionic surfactant generates wet CNF/P123 foams with a high foamability. Foam bubble size studies show that delayed Ca-induced aggregation of CNF by gluconic acid-triggered dissolution of the CaCO3 nanoparticles significantly improves the long-term stability of the wet composite foams. Drying the Ca-reinforced foam at 60 °C results in a moderate shrinkage and electron microscopy and X-ray tomography studies show that the pores became slightly oblate after drying but the overall microstructure and pore/foam bubble size distribution is preserved after drying. The elastic modulus (0.9-1.4 MPa) of Ca-reinforced composite foams with a density of 9-15 kg/m(3) is significantly higher than commercially available polyurethane foams used for thermal insulation. Copyright © 2016 Elsevier Inc. All rights reserved.

  19. Foam formation in low gravity

    NASA Technical Reports Server (NTRS)

    Wessling, Francis C.; Mcmanus, Samuel P.; Matthews, John; Patel, Darayas

    1990-01-01

    An apparatus that produced the first polyurethane foam in low gravity has been described. The chemicals were mixed together in an apparatus designed for operation in low gravity. Mixing was by means of stirring the chemicals with an electric motor and propeller in a mixing chamber. The apparatus was flown on Consort 1, the first low-gravity materials payload launched by a commercial rocket launch team. The sounding rocket flight produced over 7 min of low gravity during which a polyurethane spheroidal foam of approximately 2300 cu cm was formed. Photographs of the formation of the foam during the flight show the development of the spheroidal form. This begins as a small sphere and grows to approximately a 17-cm-diam spheroid. The apparatus will be flown again on subsequent low-gravity flights.

  20. Starch-based polyurethane/CuO nanocomposite foam: Antibacterial effects for infection control.

    PubMed

    Ashjari, Hamid Reza; Dorraji, Mir Saeed Seyed; Fakhrzadeh, Vahid; Eslami, Hosein; Rasoulifard, Mohammad Hossein; Rastgouy-Houjaghan, Mehrdad; Gholizadeh, Pourya; Kafil, Hossein Samadi

    2018-05-01

    In the present study, a new method for the synthesis of the open cell flexible polyurethane foams (PUFs) was developed by using starch powder and the modification of closed cell foam formulation. Starch is the second largest polymeric carbohydrate as a macromolecule on this planet with a large number of glucose units. Copper oxide nanoparticles (CuO NPs) were synthesized by thermal degradation method at different temperatures of 400, 600 and 800 °C as antimicrobial agents. The antimicrobial activity of CuO NPs and commercial CuO powder against the main causes of hospital infections were tested. CuO 600 was the most effective antimicrobial agent and enhanced polymer matrix tensile strength with starch powder as new polyurethane foams (PUFs) cell opener with high tensile strength. The effects of parameters on tensile strength were optimized using response surface methodology (RSM). CuO NPs and PUF had optimal conditions and were characterized by X-ray diffraction (XRD), transmission electron microscopy (TEM), scanning electron microscopy (SEM) and Fourier transform infrared spectroscopy (FT-IR). Foam synthesized at the optimal conditions had an open cell structure with high tensile strength and efficient antimicrobial activity that made them suitable to be used as an antimicrobial hospital mattress to control hospital infections. Copyright © 2018 Elsevier B.V. All rights reserved.

  1. 40 CFR 63.1306 - Reporting requirements.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ...) National Emission Standards for Hazardous Air Pollutants for Flexible Polyurethane Foam Production § 63... foam processes and in paragraph (d)(5) for rebond foam processes. (1) A list of diisocyanate storage... of pumps, valves, connectors, pressure-relief devices, and open-ended valves or lines in HAP ABA...

  2. 40 CFR 63.1306 - Reporting requirements.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ...) National Emission Standards for Hazardous Air Pollutants for Flexible Polyurethane Foam Production § 63... foam processes and in paragraph (d)(5) for rebond foam processes. (1) A list of diisocyanate storage... of pumps, valves, connectors, pressure-relief devices, and open-ended valves or lines in HAP ABA...

  3. Potential of silver nanoparticle-coated polyurethane foam as an antibacterial water filter.

    PubMed

    Jain, Prashant; Pradeep, T

    2005-04-05

    Silver nanoparticles can be coated on common polyurethane (PU) foams by overnight exposure of the foams to nanoparticle solutions. Repeated washing and air-drying yields uniformly coated PU foam, which can be used as a drinking water filter where bacterial contamination of the surface water is a health risk. Nanoparticles are stable on the foam and are not washed away by water. Morphology of the foam was retained after coating. The nanoparticle binding is due to its interaction with the nitrogen atom of the PU. Online tests were conducted with a prototypical water filter. At a flow rate of 0.5 L/min, in which contact time was of the order of a second, the output count of Escherichia coli was nil when the input water had a bacterial load of 10(5) colony-forming units (CFU) per mL. Combined with the low cost and effectiveness in its applications, the technology may have large implications to developing countries. Copyright (c) 2005 Wiley Periodicals, Inc.

  4. Thermal Protection System Application to Composite Cryotank Technology Demonstrator

    NASA Technical Reports Server (NTRS)

    Protz, Alison; Nettles, Mindy

    2015-01-01

    The EM41 Thermal Protection System (TPS) team contributed to the success of the Composite Cryotank Technology Demonstrator (CCTD) manufacturing by developing and implementing a low-cost solution to apply cryoinsulation foam on the exterior surface of the tank in the NASA Marshall Space Flight Center (MSFC) TPS Development Facility, Bldg. 4765. The TPS team used techniques developed for the smallscale composite cryotank to apply Stepanfoam S-180 polyurethane foam to the 5.5-meter CCTD using a manual spray process. Manual spray foam technicians utilized lifts and scaffolding to access the barrel and dome sections of the large-scale tank in the horizontal orientation. During manufacturing, the tank was then oriented vertically, allowing access to the final barrel section for manual spray foam application. The CCTD was the largest application of manual spray foam performed to date with the S-180 polyurethane foam and required the TPS team to employ best practices for process controls on the development article.

  5. The kinetics of polyurethane structural foam formation: Foaming and polymerization

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Rao, Rekha R.; Mondy, Lisa A.; Long, Kevin N.

    We are developing kinetic models to understand the manufacturing of polymeric foams, which evolve from low viscosity Newtonian liquids, to bubbly liquids, finally producing solid foam. Closed-form kinetics are formulated and parameterized for PMDI-10, a fast curing polyurethane, including polymerization and foaming. PMDI- 10 is chemically blown, where water and isocyanate react to form carbon dioxide. The isocyanate reacts with polyol in a competing reaction, producing polymer. Our approach is unique, though it builds on our previous work and the polymerization literature. This kinetic model follows a simplified mathematical formalism that decouples foaming and curing, including an evolving glass transitionmore » temperature to represent vitrification. This approach is based on IR, DSC, and volume evolution data, where we observed that the isocyanate is always in excess and does not affect the kinetics. Finally, the kinetics are suitable for implementation into a computational fluid dynamics framework, which will be explored in subsequent papers.« less

  6. The kinetics of polyurethane structural foam formation: Foaming and polymerization

    DOE PAGES

    Rao, Rekha R.; Mondy, Lisa A.; Long, Kevin N.; ...

    2017-02-15

    We are developing kinetic models to understand the manufacturing of polymeric foams, which evolve from low viscosity Newtonian liquids, to bubbly liquids, finally producing solid foam. Closed-form kinetics are formulated and parameterized for PMDI-10, a fast curing polyurethane, including polymerization and foaming. PMDI- 10 is chemically blown, where water and isocyanate react to form carbon dioxide. The isocyanate reacts with polyol in a competing reaction, producing polymer. Our approach is unique, though it builds on our previous work and the polymerization literature. This kinetic model follows a simplified mathematical formalism that decouples foaming and curing, including an evolving glass transitionmore » temperature to represent vitrification. This approach is based on IR, DSC, and volume evolution data, where we observed that the isocyanate is always in excess and does not affect the kinetics. Finally, the kinetics are suitable for implementation into a computational fluid dynamics framework, which will be explored in subsequent papers.« less

  7. Two approaches for introduction of wheat straw lignin into rigid polyurethane foams

    NASA Astrophysics Data System (ADS)

    Arshanitsa, A.; Paberza, A.; Vevere, L.; Cabulis, U.; Telysheva, G.

    2014-05-01

    In present work the BIOLIGNIN{trade mark, serif} obtained in the result of wheat straw organosolv processing in CIMV pilot plant (France) was investigated as a component of rigid polyurethanes (PUR) foam systems. Different separate approaches of lignin introduction into PUR foam system were studied: as filler without chemical preprocessing and as liquid lignopolyol obtained by lignin oxypropylation in alkali conditions. The incorporation of increasing amount of lignin as filler into reference PUR foam systems on the basis of mixture of commercial polyethers Lupranol 3300 and Lupranol 3422 steadily decreased the compression characteristics of foams, their dimensional stability and hydrophobicity. The complete substitution of Lupranol 3300 by lignopolyol increases its cell structure uniformity and dimensional stability and does not reduce the physical-mechanical properties of foam. In both cases the incorporation of lignin into PUR foam leads to the decreasing of maximum values of thermodegradation rates. The lignin filler can be introduced into lignopolyol based PUR foam in higher quantity than in the reference Lupranol based PUR without reduction of compression characteristics of material. In this work the optimal lignin content in the end product - PUR foam as both polyol and filler is 16%.

  8. Toluene diisocyanate emission to air and migration to a surface from a flexible polyurethane foam.

    PubMed

    Vangronsveld, Erik; Berckmans, Steven; Spence, Mark

    2013-06-01

    Flexible polyurethane foam (FPF) is produced from the reaction of toluene diisocyanate (TDI) and polyols. Because of the potential for respiratory sensitization following exposure to TDI, concerns have been raised about potential consumer exposure to TDI from residual 'free TDI' in FPF products. Limited and conflicting results exist in the literature concerning the presence of unreacted TDI remaining in FPF as determined by various solvent extraction and analysis techniques. Because residual TDI results are most often intended for application in assessment of potential human exposure to TDI from FPF products, testing techniques that more accurately simulated human contact with foam were designed. To represent inhalation exposure to TDI from polyurethane foam, a test that measured the emission of TDI to air was conducted. For simulation of human dermal exposure to TDI from polyurethane foam, a migration test technique was designed. Emission of TDI to air was determined for a representative FPF using three different emission test cells. Two were commercially available cells that employ air flow over the surface of the foam [the Field and Laboratory Emission Cell (FLEC®) and the Micro-Chamber/Thermal Extraction™ cell]. The third emission test cell was of a custom design and features air flow through the foam sample rather than over the foam surface. Emitted TDI in the air of the test cells was trapped using glass fiber filters coated with 1-(2-methoxyphenyl)-piperazine (MP), a commonly used derivatizing agent for diisocyanates. The filters were subsequently desorbed and analyzed by liquid chromatography/mass spectrometry. Measurement of TDI migration from representative foam was accomplished by placing glass fiber filters coated with MP on the outer surfaces of a foam disk and then compressing the filters against the disk using a clamping apparatus for periods of 8 and 24 h. The sample filters were subsequently desorbed and analyzed in the same manner as for the emission tests. Although the foam tested had detectable levels of solvent-extractable TDI (56ng TDI g(-1) foam for the foam used in emissions tests; 240-2800ng TDI g(-1) foam for the foam used in migration tests), no TDI was detected in any of the emission or migration tests. Method detection limits (MDLs) for the emissions tests ranged from 0.03 to 0.5ng TDI g(-1) foam (0.002-0.04ng TDI cm(-2) of foam surface), whereas those for the migration tests were 0.73ng TDI g(-1) foam (0.16ng TDI cm(-2) of foam surface). Of the three emission test methods used, the FLEC® had the lowest relative MDLs (by a factor of 3-10) by virtue of its high chamber loading factor. In addition, the FLEC® cell offers well-established conformity with emission testing standard methods.

  9. 40 CFR Table 3 to Subpart III of... - Compliance Requirements for Slabstock Foam Production Affected Sources Complying With the...

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... Foam Production Affected Sources Complying With the Emission Point Specific Limitations 3 Table 3 to... Standards for Hazardous Air Pollutants for Flexible Polyurethane Foam Production Pt. 63, Subpt. III, Table 3 Table 3 to Subpart III of Part 63—Compliance Requirements for Slabstock Foam Production Affected Sources...

  10. 40 CFR Table 3 to Subpart III of... - Compliance Requirements for Slabstock Foam Production Affected Sources Complying With the...

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... Foam Production Affected Sources Complying With the Emission Point Specific Limitations 3 Table 3 to...) National Emission Standards for Hazardous Air Pollutants for Flexible Polyurethane Foam Production Pt. 63, Subpt. III, Table 3 Table 3 to Subpart III of Part 63—Compliance Requirements for Slabstock Foam...

  11. 40 CFR Table 3 to Subpart III of... - Compliance Requirements for Slabstock Foam Production Affected Sources Complying With the...

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... Foam Production Affected Sources Complying With the Emission Point Specific Limitations 3 Table 3 to... Standards for Hazardous Air Pollutants for Flexible Polyurethane Foam Production Pt. 63, Subpt. III, Table 3 Table 3 to Subpart III of Part 63—Compliance Requirements for Slabstock Foam Production Affected Sources...

  12. 40 CFR Table 3 to Subpart III of... - Compliance Requirements for Slabstock Foam Production Affected Sources Complying With the...

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... Foam Production Affected Sources Complying With the Emission Point Specific Limitations 3 Table 3 to... Standards for Hazardous Air Pollutants for Flexible Polyurethane Foam Production Pt. 63, Subpt. III, Table 3 Table 3 to Subpart III of Part 63—Compliance Requirements for Slabstock Foam Production Affected Sources...

  13. 40 CFR Table 3 to Subpart III of... - Compliance Requirements for Slabstock Foam Production Affected Sources Complying With the...

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... Foam Production Affected Sources Complying With the Emission Point Specific Limitations 3 Table 3 to...) National Emission Standards for Hazardous Air Pollutants for Flexible Polyurethane Foam Production Pt. 63, Subpt. III, Table 3 Table 3 to Subpart III of Part 63—Compliance Requirements for Slabstock Foam...

  14. 40 CFR Table 4 to Subpart III of... - Compliance Requirements for Slabstock Foam Production Affected Sources Complying With the Source...

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ...) National Emission Standards for Hazardous Air Pollutants for Flexible Polyurethane Foam Production Pt. 63, Subpt. III, Table 4 Table 4 to Subpart III of Part 63—Compliance Requirements for Slabstock Foam... Foam Production Affected Sources Complying With the Source-Wide Emission Limitation 4 Table 4 to...

  15. 40 CFR Table 4 to Subpart III of... - Compliance Requirements for Slabstock Foam Production Affected Sources Complying With the Source...

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ...) National Emission Standards for Hazardous Air Pollutants for Flexible Polyurethane Foam Production Pt. 63, Subpt. III, Table 4 Table 4 to Subpart III of Part 63—Compliance Requirements for Slabstock Foam... Foam Production Affected Sources Complying With the Source-Wide Emission Limitation 4 Table 4 to...

  16. EPA SPF Insulation Research Update | Science Inventory | US ...

    EPA Pesticide Factsheets

    This is a non-technical (no data) presentation that is intended to inform ACC/CPI about our intended approach to full-scale emissions testing that includes the application of spray foam in an environmental chamber. The presentation describes the approach to emissions characterization, types of measurement systems to be employed, and expected outcomes from the planned tests. Purpose of this presentation is to update industry stakeholders (American Chemistry Council, Center for Polyurethanes) on status of the spray polyurethane foam insulation emissions methods development task.

  17. Treatment of concentrated industrial wastewaters originating from oil shale and the like by electrolysis polyurethane foam interaction

    DOEpatents

    Tiernan, Joan E.

    1991-01-01

    Highly concentrated and toxic petroleum-based and synthetic fuels wastewaters such as oil shale retort water are treated in a unit treatment process by electrolysis in a reactor containing oleophilic, ionized, open-celled polyurethane foams and subjected to mixing and l BACKGROUND OF THE INVENTION The invention described herein arose in the course of, or under, Contract No. DE-AC03-76SF00098 between the U.S. Department of Energy and the University of California.

  18. 46 CFR 160.010-1 - Incorporation by reference.

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ... Specification, Plastic Material, Cellular Polyurethane, Foam-In-Place, Rigid (2 and 4 Pounds per Cubic Foot....mil/quicksearch/. (1) MIL-P-19644C, Military Specification, Plastic Molding Material (Polystyrene Foam...

  19. 46 CFR 160.010-1 - Incorporation by reference.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ... Specification, Plastic Material, Cellular Polyurethane, Foam-In-Place, Rigid (2 and 4 Pounds per Cubic Foot....mil/quicksearch/. (1) MIL-P-19644C, Military Specification, Plastic Molding Material (Polystyrene Foam...

  20. 40 CFR 63.1306 - Reporting requirements.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... Standards for Hazardous Air Pollutants for Flexible Polyurethane Foam Production § 63.1306 Reporting... the information listed in paragraph (d)(4) of this section for molded foam processes and in paragraph (d)(5) for rebond foam processes. (1) A list of diisocyanate storage vessels, along with a record of...

  1. 40 CFR 63.1306 - Reporting requirements.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... for Hazardous Air Pollutants for Flexible Polyurethane Foam Production § 63.1306 Reporting... the information listed in paragraph (d)(4) of this section for molded foam processes and in paragraph (d)(5) for rebond foam processes. (1) A list of diisocyanate storage vessels, along with a record of...

  2. 40 CFR 63.1306 - Reporting requirements.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... for Hazardous Air Pollutants for Flexible Polyurethane Foam Production § 63.1306 Reporting... the information listed in paragraph (d)(4) of this section for molded foam processes and in paragraph (d)(5) for rebond foam processes. (1) A list of diisocyanate storage vessels, along with a record of...

  3. Dielectric properties of novel polyurethane-PZT-graphite foam composites

    NASA Astrophysics Data System (ADS)

    Tolvanen, Jarkko; Hannu, Jari; Nelo, Mikko; Juuti, Jari; Jantunen, Heli

    2016-09-01

    Flexible foam composite materials offer multiple benefits to future electronic applications as the rapid development of the electronics industry requires smaller, more efficient, and lighter materials to further develop foldable and wearable applications. The aims of this work were to examine the electrical properties of three- and four-phase novel foam composites in different conditions, find the optimal mixture for four-phase foam composites, and study the combined effects of lead zirconate titanate (PZT) and graphite fillers. The flexible and highly compressible foams were prepared in a room-temperature mixing process using polyurethane, PZT, and graphite components as well as their combinations, in which air acted as one phase. In three-phase foams the amount of PZT varied between 20 and 80 wt% and the amount of graphite, between 1 and 15 wt%. The four-phase foams were formed by adding 40 wt% of PZT while the amount of graphite ranged between 1 and 15 wt%. The presented results and materials could be utilized to develop new flexible and soft sensor applications by means of material technology.

  4. Mitigating ballast fouling and enhancing rail freight capacity.

    DOT National Transportation Integrated Search

    2012-11-01

    In this report, an application using polyurethane void filling and particle bonding technology for stabilizing ballast is : evaluated. Application of rigid-polyurethane foam (RPF) as an in situ stabilization method does not require premixing : with a...

  5. 40 CFR 463.1 - Applicability.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... polyurethane foam are not subject to the effluent limitations guidelines and standards in this part. Water used... used to further mold or form the reticulated foam are subject, however, to this regulation if they...

  6. 40 CFR 463.1 - Applicability.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... polyurethane foam are not subject to the effluent limitations guidelines and standards in this part. Water used... used to further mold or form the reticulated foam are subject, however, to this regulation if they...

  7. 40 CFR 463.1 - Applicability.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... polyurethane foam are not subject to the effluent limitations guidelines and standards in this part. Water used... used to further mold or form the reticulated foam are subject, however, to this regulation if they...

  8. Phenolic cutter for machining foam insulation

    NASA Technical Reports Server (NTRS)

    Blair, T. A.; Miller, A. C.; Price, B. W.; Stiles, W. S.

    1970-01-01

    Pre-pregged fiber glass is an efficient abrasive for machining polystyrene and polyurethane foams. It bonds easily to any cutter base made of aluminum, steel, or phenolic, is inexpensive, and is readily available.

  9. Rigid Polyurethane Foam (RPF) Technology for Countermines (Sea) Program Phase II

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    WOODFIN,RONALD L.; FAUCETT,DAVID L.; HANCE,BRADLEY G.

    This Phase II report documents the results of one subtask initiated under the joint Department of Energy (DOE)/Department of Defense (DoD) Memorandum of Understanding (MOU) for Countermine Warfare. The development of Rigid Polyurethane Foams for neutralization of mines and barriers in amphibious assault was the objective of the tasking. This phase of the program concentrated on formation of RPF in water, explosive mine simulations, and development of foam and fabric pontoons. Field experimentation was done primarily at the Energetic Materials Research and Testing Center (EMRTC) of the New Mexico Institute of Mining and Technology, Socorro, NM between February 1996 andmore » September 1998.« less

  10. Diplogelasinospora grovesii IMI 171018 immobilized in polyurethane foam. An efficient biocatalyst for stereoselective reduction of ketones.

    PubMed

    Quezada, M A; Carballeira, J D; Sinisterra, J V

    2012-05-01

    Diplogelasinospora grovesii has been reported as a very active biocatalyst in the reduction of ketones. Along the text, the properties of this filamentous fungus as an immobilized catalyst are described. For this purpose, several immobilization supports as agar and polyurethane foam were tested. Experimental assays were also performed to test different co-substrates for the regeneration of the required enzyme cofactor. The fungus immobilized in polyurethane foam lead to the most stable and active catalyst. This derivative, using i-PrOH as co-substrate, could be reused at least 18 times without appreciable activity loss (>90% activity remains). Kinetic runs experiments shown that the reduction of cyclohexanone, selected as model substrate, followed a pseudo-first kinetic order and that the rate controlling step was the mass transfer through the cell wall. The deactivation kinetic constants were also determined. The reduction of different chiral ketones showed that the ketone reductase activity followed the Prelog's rule. Copyright © 2012 Elsevier Ltd. All rights reserved.

  11. Polyurethane foam (PUF) disks passive air samplers: wind effect on sampling rates.

    PubMed

    Tuduri, Ludovic; Harner, Tom; Hung, Hayley

    2006-11-01

    Different passive sampler housings were evaluated for their wind dampening ability and how this might translate to variability in sampler uptake rates. Polyurethane foam (PUF) disk samplers were used as the sampling medium and were exposed to a PCB-contaminated atmosphere in a wind tunnel. The effect of outside wind speed on PUF disk sampling rates was evaluated by exposing polyurethane foam (PUF) disks to a PCB-contaminated air stream in a wind tunnel over air velocities in the range 0 to 1.75 m s-1. PUF disk sampling rates increased gradually over the range 0-0.9 m s-1 at approximately 4.5-14.6 m3 d-1 and then increased sharply to approximately 42 m3 d-1 at approximately 1.75 m s-1 (sum of PCBs). The results indicate that for most field deployments the conventional 'flying saucer' housing adequately dampens the wind effect and will yield approximately time-weighted air concentrations.

  12. 40 CFR 63.1303 - Monitoring requirements.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... Standards for Hazardous Air Pollutants for Flexible Polyurethane Foam Production § 63.1303 Monitoring... HAP ABA and polyol added to the foam production line at the mixhead. (1) The owner or operator of each... shall continuously monitor the amount of polyol added at the mixhead when foam is being poured, in...

  13. 40 CFR 63.1303 - Monitoring requirements.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ...) National Emission Standards for Hazardous Air Pollutants for Flexible Polyurethane Foam Production § 63...) Monitoring for HAP ABA and polyol added to the foam production line at the mixhead. (1) The owner or operator... slabstock affected sources shall continuously monitor the amount of polyol added at the mixhead when foam is...

  14. 40 CFR 63.1303 - Monitoring requirements.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ...) National Emission Standards for Hazardous Air Pollutants for Flexible Polyurethane Foam Production § 63...) Monitoring for HAP ABA and polyol added to the foam production line at the mixhead. (1) The owner or operator... slabstock affected sources shall continuously monitor the amount of polyol added at the mixhead when foam is...

  15. 40 CFR 63.1303 - Monitoring requirements.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... Standards for Hazardous Air Pollutants for Flexible Polyurethane Foam Production § 63.1303 Monitoring... HAP ABA and polyol added to the foam production line at the mixhead. (1) The owner or operator of each... shall continuously monitor the amount of polyol added at the mixhead when foam is being poured, in...

  16. 40 CFR 63.1303 - Monitoring requirements.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... Standards for Hazardous Air Pollutants for Flexible Polyurethane Foam Production § 63.1303 Monitoring... HAP ABA and polyol added to the foam production line at the mixhead. (1) The owner or operator of each... shall continuously monitor the amount of polyol added at the mixhead when foam is being poured, in...

  17. A randomized, controlled trial of negative pressure wound therapy of pressure ulcers via a novel polyurethane foam.

    PubMed

    Wagstaff, Marcus James Dermot; Driver, Sara; Coghlan, Patrick; Greenwood, John Edward

    2014-01-01

    The objectives of the study were (1) to look for any local, clinically apparent response, within and around a debrided wound, to a novel biocompatible polyurethane foam during repeated, short-term implantation, and (2) to assess the material's efficacy as a negative pressure wound therapy (NPWT) interface compared with a widely used, commercially available foam. Twenty pressure ulcers in 18 patients underwent surgical debridement, then randomization to receive novel treatment or control foam as the wound interface for NPWT. Dressing changes every 2-3 days allowed qualitative wound assessment and quantitative measurement to compare outcomes. No adverse reaction was observed in any patient receiving the new foam. The new "novel foam" performed as a NPWT interface as effectively as the control "standard foam." In deep wounds, the new foam was easier to remove, fragmented less, and showed less retention than the control foam. No marginal in-growth occurred, making removal less traumatic and reducing bleeding from cavity wall granulations. The results support previous large animal studies, and independent ISO10993 testing, that the new foam is safe and biocompatible. Its efficacy as an NPWT interface, nontraumatic removal with low fragmentation and retention rate, favors the new material, especially in deep cavity wounds. © 2014 by the Wound Healing Society.

  18. Validation of Heat Transfer Thermal Decomposition and Container Pressurization of Polyurethane Foam.

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Scott, Sarah Nicole; Dodd, Amanda B.; Larsen, Marvin E.

    Polymer foam encapsulants provide mechanical, electrical, and thermal isolation in engineered systems. In fire environments, gas pressure from thermal decomposition of polymers can cause mechanical failure of sealed systems. In this work, a detailed uncertainty quantification study of PMDI-based polyurethane foam is presented to assess the validity of the computational model. Both experimental measurement uncertainty and model prediction uncertainty are examined and compared. Both the mean value method and Latin hypercube sampling approach are used to propagate the uncertainty through the model. In addition to comparing computational and experimental results, the importance of each input parameter on the simulation resultmore » is also investigated. These results show that further development in the physics model of the foam and appropriate associated material testing are necessary to improve model accuracy.« less

  19. Elastic superlattices with simultaneously negative effective mass density and shear modulus

    NASA Astrophysics Data System (ADS)

    Solís-Mora, I. S.; Palomino-Ovando, M. A.; Pérez-Rodríguez, F.

    2013-03-01

    We investigate the vibrational properties of superlattices with layers of rubber and polyurethane foam, which can be either conventional or auxetic. Phononic dispersion calculations show a second pass band for transverse modes inside the lowest band gap of the longitudinal modes. In such a band, the superlattices behave as a double-negative elastic metamaterial since the effective dynamic mass density and shear modulus are both negative. The pass band is associated to a Fabry-Perot resonance band which turns out to be very narrow as a consequence of the high contrast between the acoustic impedances of the superlattice components.

  20. Design of single piece sabot for a single stage gas gun

    NASA Astrophysics Data System (ADS)

    Vemparala, Vignesh; Mathew, Arun Tom; Rao Koka, Tirumala

    2017-11-01

    Single piece sabot is a vital part in single stage gas guns for impact testing in aerospace industries. Depending on the type of projectile used the design of sabot varies to accommodate the testing equipment. The velocity of the projectile exiting the barrel is dependent on the material and shape of the sabot used. The material selected for the design of sabot is rigid polyurethane foam, due to their low elastic modulus and low density. Two samples of rigid PU foam is taken and tests are performed to get their exact material properties. These properties are incorporated in numerical simulation to determine the best fit for practical use. Since the PU foams has a wide range of porosity which plays a prominent role in deciding the exit velocity and accuracy of the projectile coming out of the barrel. By optimisation, to the best suitable material sample can be determined.

  1. Polyurethane Foam Roofing.

    DTIC Science & Technology

    1987-04-01

    degradation of foam .... ............... ... 53 38 Wet film gauge ....... ..................... 55 39 Peak dry film thickness gauge ... ........... ... 56 40...openings, splits and small holes or other imperfections as the liquid mixture expands and sets to form the finished foam . In addition, they can be applied...are based on the foam insulation thickness desired and the generic type and dry film mil thickness (DFT) of elastomeric protective coating selected

  2. 40 CFR Table 5 to Subpart III of... - Compliance Requirements for Molded and Rebond Foam Production Affected Sources

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... Flexible Polyurethane Foam Production Pt. 63, Subpt. III, Table 5 Table 5 to Subpart III of Part 63—Compliance Requirements for Molded and Rebond Foam Production Affected Sources Emission point Emission point... Rebond Foam Production Affected Sources 5 Table 5 to Subpart III of Part 63 Protection of Environment...

  3. 40 CFR Table 4 to Subpart III of... - Compliance Requirements for Slabstock Foam Production Affected Sources Complying With the Source...

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... Standards for Hazardous Air Pollutants for Flexible Polyurethane Foam Production Pt. 63, Subpt. III, Table 4 Table 4 to Subpart III of Part 63—Compliance Requirements for Slabstock Foam Production Affected Sources... Foam Production Affected Sources Complying With the Source-Wide Emission Limitation 4 Table 4 to...

  4. 40 CFR Table 5 to Subpart III of... - Compliance Requirements for Molded and Rebond Foam Production Affected Sources

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... Pollutants for Flexible Polyurethane Foam Production Pt. 63, Subpt. III, Table 5 Table 5 to Subpart III of Part 63—Compliance Requirements for Molded and Rebond Foam Production Affected Sources Emission point... Rebond Foam Production Affected Sources 5 Table 5 to Subpart III of Part 63 Protection of Environment...

  5. 40 CFR Table 5 to Subpart III of... - Compliance Requirements for Molded and Rebond Foam Production Affected Sources

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... Pollutants for Flexible Polyurethane Foam Production Pt. 63, Subpt. III, Table 5 Table 5 to Subpart III of Part 63—Compliance Requirements for Molded and Rebond Foam Production Affected Sources Emission point... Rebond Foam Production Affected Sources 5 Table 5 to Subpart III of Part 63 Protection of Environment...

  6. 40 CFR Table 5 to Subpart III of... - Compliance Requirements for Molded and Rebond Foam Production Affected Sources

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... Flexible Polyurethane Foam Production Pt. 63, Subpt. III, Table 5 Table 5 to Subpart III of Part 63—Compliance Requirements for Molded and Rebond Foam Production Affected Sources Emission point Emission point... Rebond Foam Production Affected Sources 5 Table 5 to Subpart III of Part 63 Protection of Environment...

  7. 40 CFR Table 5 to Subpart III of... - Compliance Requirements for Molded and Rebond Foam Production Affected Sources

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... Flexible Polyurethane Foam Production Pt. 63, Subpt. III, Table 5 Table 5 to Subpart III of Part 63—Compliance Requirements for Molded and Rebond Foam Production Affected Sources Emission point Emission point... Rebond Foam Production Affected Sources 5 Table 5 to Subpart III of Part 63 Protection of Environment...

  8. 40 CFR Table 4 to Subpart III of... - Compliance Requirements for Slabstock Foam Production Affected Sources Complying With the Source...

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... Standards for Hazardous Air Pollutants for Flexible Polyurethane Foam Production Pt. 63, Subpt. III, Table 4 Table 4 to Subpart III of Part 63—Compliance Requirements for Slabstock Foam Production Affected Sources... Foam Production Affected Sources Complying With the Source-Wide Emission Limitation 4 Table 4 to...

  9. Repairing Foam Insulation

    NASA Technical Reports Server (NTRS)

    Corbin, J.; Buras, D.

    1986-01-01

    Large holes in polyurethane foam insulation repaired reliably by simple method. Little skill needed to apply method, used for overhead repairs as well as for those in other orientations. Plug positioned in hole to be filled and held in place with mounting fixture. Fresh liquid foam injected through plug to bond it in place. As foam cures and expands, it displaces plug outward. Protrusion later removed.

  10. 40 CFR Table 4 to Subpart III of... - Compliance Requirements for Slabstock Foam Production Affected Sources Complying With the Source...

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... Standards for Hazardous Air Pollutants for Flexible Polyurethane Foam Production Pt. 63, Subpt. III, Table 4 Table 4 to Subpart III of Part 63—Compliance Requirements for Slabstock Foam Production Affected Sources... Foam Production Affected Sources Complying With the Source-Wide Emission Limitation 4 Table 4 to...

  11. Tribology and Friction of Soft Materials: Mississippi State Case Study

    DTIC Science & Technology

    2010-03-18

    elastomers , foams, and fabrics. B. Develop internal state variable (ISV) material model. Model will be calibrated using database and verified...Rubbers Natural rubber Santoprene (Vulcanized Elastomer ) Styrene Butadiene Rubber (SBR) Foams Polypropylene Foam Polyurethane Foam Fabrics Kevlar...Axially symmetric model PC Disk PC Numerical Implementation in FEM Codes Experiment SEM Optical methods ISV Model Void Nucleation FEM Analysis

  12. Polyurethane foam-covered breast implants: a justified choice?

    PubMed

    Scarpa, C; Borso, G F; Vindigni, V; Bassetto, F

    2015-01-01

    Even if the safety of the polyurethane prosthesis has been the subject of many studies and professional and public controversies. Nowadays, polyurethane covered implants are very popular in plastic surgery for the treatment of capsular contracture. We have identified 41 papers (1 is a communication of the FDA) by using search browsers such as Pubmed, Medline, and eMedicine. Eleven manuscripts have been used for an introduction, and the remaining thirty have been subdivided into three tables whose results have been summarized in three main chapters: (1) capsular formation and contracture, (2) complications, (3) biodegradation and cancer risk. (1) The polyurethanic capsule is a well defined foreign body reaction characterized by synovial metaplasia, a thin layer of disarranged collagen fibers and a high vascularization. These features make possible a "young" capsule and a low occurrence of capsular contracture even over a long period (10 years); (2) the polyurethane implants may be difficult to remove but there is no evidence that they cause an increase in the other complications; (3) there is no evidence of polyurethane related cancer in long-term studies (after 5 years). Polyurethane foam covered breast implants remain a valid choice for the treatment of capsular contracture even if it would be very useful to verify the ease of removal of the prosthesis and to continue investigations on biodegradation products.

  13. Influence of Orientation and Radiative Heat Transfer on Aluminum Foams in Buoyancy-Induced Convection

    PubMed Central

    Billiet, Marijn; De Schampheleire, Sven; Huisseune, Henk; De Paepe, Michel

    2015-01-01

    Two differently-produced open-cell aluminum foams were compared to a commercially available finned heat sink. Further, an aluminum plate and block were tested as a reference. All heat sinks have the same base plate dimensions of four by six inches. The first foam was made by investment casting of a polyurethane preform and has a porosity of 0.946 and a pore density of 10 pores per linear inch. The second foam is manufactured by casting over a solvable core and has a porosity of 0.85 and a pore density of 2.5 pores per linear inch. The effects of orientation and radiative heat transfer are experimentally investigated. The heat sinks are tested in a vertical and horizontal orientation. The effect of radiative heat transfer is investigated by comparing a painted/anodized heat sink with an untreated one. The heat flux through the heat sink for a certain temperature difference between the environment and the heat sink’s base plate is used as the performance indicator. For temperature differences larger than 30 ∘C, the finned heat sink outperforms the in-house-made aluminum foam heat sink on average by 17%. Furthermore, the in-house-made aluminum foam dissipates on average 12% less heat than the other aluminum foam for a temperature difference larger than 40 ∘C. By painting/anodizing the heat sinks, the heat transfer rate increased on average by 10% to 50%. Finally, the thermal performance of the horizontal in-house-made aluminum foam heat sink is up to 18% larger than the one of the vertical aluminum foam heat sink. PMID:28793601

  14. Experimental Tests on the Composite Foam Sandwich Pipes Subjected to Axial Load

    NASA Astrophysics Data System (ADS)

    Li, Feng; Zhao, QiLin; Xu, Kang; Zhang, DongDong

    2015-12-01

    Compared to the composite thin-walled tube, the composite foam sandwich pipe has better local flexural rigidity, which can take full advantage of the high strength of composite materials. In this paper, a series of composite foam sandwich pipes with different parameters were designed and manufactured using the prefabricated polyurethane foam core-skin co-curing molding technique with E-glass fabric prepreg. The corresponding axial-load compressive tests were conducted to investigate the influence factors that experimentally determine the axial compressive performances of the tubes. In the tests, the detailed failure process and the corresponding load-displacement characteristics were obtained; the influence rules of the foam core density, surface layer thickness, fiber ply combination and end restraint on the failure modes and ultimate bearing capacity were studied. Results indicated that: (1) the fiber ply combination, surface layer thickness and end restraint have a great influence on the ultimate load bearing capacity; (2) a reasonable fiber ply combination and reliable interfacial adhesion not only optimize the strength but also transform the failure mode from brittle failure to ductile failure, which is vital to the fully utilization of the composite strength of these composite foam sandwich pipes.

  15. Foam-filled cushions for sliding trays

    NASA Technical Reports Server (NTRS)

    Nahin, S. B.; Robb, P. H.

    1980-01-01

    Polytetrafluoroethylene tube filled with polyurethane foam forms low friction sliding surface that cushions vibrations and absorbs manufacturing tolerances and misalignment. Possible uses include packaging of components for shipping and seals for doors in lockers, cars, and refrigerators.

  16. Biodegradative Activities of Selected Environmental Fungi on a Polyester Polyurethane Varnish and Polyether Polyurethane Foams

    PubMed Central

    Álvarez-Barragán, Joyce; Domínguez-Malfavón, Lilianha; Vargas-Suárez, Martín; González-Hernández, Ricardo; Aguilar-Osorio, Guillermo

    2016-01-01

    ABSTRACT Polyurethane (PU) is widely used in many aspects of modern life because of its versatility and resistance. However, PU waste disposal generates large problems, since it is slowly degraded, there are limited recycling processes, and its destruction may generate toxic compounds. In this work, we isolated fungal strains able to grow in mineral medium with a polyester PU (PS-PU; Impranil DLN) or a polyether PU (PE-PU; Poly Lack) varnish as the only carbon source. Of the eight best Impranil-degrading strains, the six best degraders belonged to the Cladosporium cladosporioides complex, including the species C. pseudocladosporioides, C. tenuissimum, C. asperulatum, and C. montecillanum, and the two others were identified as Aspergillus fumigatus and Penicillium chrysogenum. The best Impranil degrader, C. pseudocladosporioides strain T1.PL.1, degraded up to 87% after 14 days of incubation. Fourier transform infrared (FTIR) spectroscopy analysis of Impranil degradation by this strain showed a loss of carbonyl groups (1,729 cm−1) and N—H bonds (1,540 and 1,261 cm−1), and gas chromatography-mass spectrometry (GC-MS) analysis showed a decrease in ester compounds and increase in alcohols and hexane diisocyanate, indicating the hydrolysis of ester and urethane bonds. Extracellular esterase and low urease, but not protease activities were detected at 7 and 14 days of culture in Impranil. The best eight Impranil-degrading fungi were also able to degrade solid foams of the highly recalcitrant PE-PU type to different extents, with the highest levels generating up to 65% of dry-weight losses not previously reported. Scanning electron microscopy (SEM) analysis of fungus-treated foams showed melted and thinner cell wall structures than the non-fungus-treated ones, demonstrating fungal biodegradative action on PE-PU. IMPORTANCE Polyurethane waste disposal has become a serious problem. In this work, fungal strains able to efficiently degrade different types of polyurethanes are reported, and their biodegradative activity was studied by different experimental approaches. Varnish biodegradation analyses showed that fungi were able to break down the polymer in some of their precursors, offering the possibility that they may be recovered and used for new polyurethane synthesis. Also, the levels of degradation of solid polyether polyurethane foams reported in this work have never been observed previously. Isolation of efficient polyurethane-degrading microorganisms and delving into the mechanisms they used to degrade the polymer provide the basis for the development of biotechnological processes for polyurethane biodegradation and recycling. PMID:27316963

  17. Biodegradative Activities of Selected Environmental Fungi on a Polyester Polyurethane Varnish and Polyether Polyurethane Foams.

    PubMed

    Álvarez-Barragán, Joyce; Domínguez-Malfavón, Lilianha; Vargas-Suárez, Martín; González-Hernández, Ricardo; Aguilar-Osorio, Guillermo; Loza-Tavera, Herminia

    2016-09-01

    Polyurethane (PU) is widely used in many aspects of modern life because of its versatility and resistance. However, PU waste disposal generates large problems, since it is slowly degraded, there are limited recycling processes, and its destruction may generate toxic compounds. In this work, we isolated fungal strains able to grow in mineral medium with a polyester PU (PS-PU; Impranil DLN) or a polyether PU (PE-PU; Poly Lack) varnish as the only carbon source. Of the eight best Impranil-degrading strains, the six best degraders belonged to the Cladosporium cladosporioides complex, including the species C. pseudocladosporioides, C. tenuissimum, C. asperulatum, and C. montecillanum, and the two others were identified as Aspergillus fumigatus and Penicillium chrysogenum The best Impranil degrader, C. pseudocladosporioides strain T1.PL.1, degraded up to 87% after 14 days of incubation. Fourier transform infrared (FTIR) spectroscopy analysis of Impranil degradation by this strain showed a loss of carbonyl groups (1,729 cm(-1)) and N-H bonds (1,540 and 1,261 cm(-1)), and gas chromatography-mass spectrometry (GC-MS) analysis showed a decrease in ester compounds and increase in alcohols and hexane diisocyanate, indicating the hydrolysis of ester and urethane bonds. Extracellular esterase and low urease, but not protease activities were detected at 7 and 14 days of culture in Impranil. The best eight Impranil-degrading fungi were also able to degrade solid foams of the highly recalcitrant PE-PU type to different extents, with the highest levels generating up to 65% of dry-weight losses not previously reported. Scanning electron microscopy (SEM) analysis of fungus-treated foams showed melted and thinner cell wall structures than the non-fungus-treated ones, demonstrating fungal biodegradative action on PE-PU. Polyurethane waste disposal has become a serious problem. In this work, fungal strains able to efficiently degrade different types of polyurethanes are reported, and their biodegradative activity was studied by different experimental approaches. Varnish biodegradation analyses showed that fungi were able to break down the polymer in some of their precursors, offering the possibility that they may be recovered and used for new polyurethane synthesis. Also, the levels of degradation of solid polyether polyurethane foams reported in this work have never been observed previously. Isolation of efficient polyurethane-degrading microorganisms and delving into the mechanisms they used to degrade the polymer provide the basis for the development of biotechnological processes for polyurethane biodegradation and recycling. Copyright © 2016, American Society for Microbiology. All Rights Reserved.

  18. Panelized wall system with foam core insulation

    DOEpatents

    Kosny, Jan [Oak Ridge, TN; Gaskin, Sally [Houston, TX

    2009-10-20

    A wall system includes a plurality of wall members, the wall members having a first metal panel, a second metal panel, and an insulating core between the first panel and the second panel. At least one of the first panel and the second panel include ridge portions. The insulating core can be a foam, such as a polyurethane foam. The foam can include at least one opacifier to improve the k-factor of the foam.

  19. Soft and Flexible Bilayer Thermoplastic Polyurethane Foam for Development of Bioinspired Artificial Skin.

    PubMed

    Li, Huan; Sinha, Tridib K; Oh, Jeong Seok; Kim, Jin Kuk

    2018-04-25

    Inspired by the epidermis-dermis composition of human skin, here we have simply developed a lightweight, robust, flexible, and biocompatible single-electrode triboelectric nanogenerator (S-TENG)-based prototype of bilayer artificial skin, by attaching one induction electrode with unfoamed skin layer of microcellular thermoplastic polyurethane (TPU) foam, which shows high-performance object manipulation [by responding differently toward different objects, viz., aluminum foil, balloon, cotton glove, human finger, glass, rubber glove, artificial leather, polyimide, poly(tetrafluoroethylene) (PTFE), paper, and wood], due to electrification and electrostatic induction during contact with the objects having different chemical functionalities. Comparative foaming behavior of ecofriendly supercritical fluids, viz., CO 2 over N 2 under variable temperatures (e.g., 130 and 150 °C) and constant pressure (15 MPa), have been examined here to pursue the soft and flexible triboelectric TPU foam. The foam derived by CO 2 foaming at 150 °C has been prioritized for development of S-TENG. Foam derived by CO 2 foaming at 130 °C did not respond as well due to the smaller cell size, higher hardness, and thicker skin. Inflexible N 2 -derived foam was not considered for S-TENG fabrication. Object manipulation performance has been visualized by principal component analysis (PCA), which shows good discrimination among responses to different objects.

  20. Modeling Heat Transfer and Pressurization of Polymeric Methylene Diisocyanate (PMDI) Polyurethane Foam in a Sealed Container.

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Scott, Sarah Nicole

    Polymer foam encapsulants provide mechanical, electrical, and thermal isolation in engineered systems. It can be advantageous to surround objects of interest, such as electronics, with foams in a hermetically sealed container to protect the electronics from hostile en vironments, such as a crash that produces a fire. However, i n fire environments, gas pressure from thermal decomposition of foams can cause mechanical failure of the sealed system . In this work, a detailed study of thermally decomposing polymeric methylene diisocyanate (PMDI) - polyether - polyol based polyurethane foam in a sealed container is presented . Both experimental and computational workmore » is discussed. Three models of increasing physics fidelity are presented: No Flow, Porous Media, and Porous Media with VLE. Each model us described in detail, compared to experiment , and uncertainty quantification is performed. While the Porous Media with VLE model matches has the best agreement with experiment, it also requires the most computational resources.« less

  1. Nano-Aramid Fiber Reinforced Polyurethane Foam

    NASA Technical Reports Server (NTRS)

    Semmes, Edmund B.; Frances, Arnold

    2008-01-01

    Closed cell polyurethane and, particularly, polyisocyanurate foams are a large family of flexible and rigid products the result of a reactive two part process wherein a urethane based polyol is combined with a foaming or "blowing" agent to create a cellular solid at room temperature. The ratio of reactive components, the constituency of the base materials, temperature, humidity, molding, pouring, spraying and many other processing techniques vary greatly. However, there is no known process for incorporating reinforcing fibers small enough to be integrally dispersed within the cell walls resulting in superior final products. The key differentiating aspect from the current state of art resides in the many processing technologies to be fully developed from the novel concept of milled nano pulp aramid fibers and their enabling entanglement capability fully enclosed within the cell walls of these closed cell urethane foams. The authors present the results of research and development of reinforced foam processing, equipment development, strength characteristics and the evolution of its many applications.

  2. Graded porous polyurethane foam: a potential scaffold for oro-maxillary bone regeneration.

    PubMed

    Giannitelli, S M; Basoli, F; Mozetic, P; Piva, P; Bartuli, F N; Luciani, F; Arcuri, C; Trombetta, M; Rainer, A; Licoccia, S

    2015-06-01

    Bone tissue engineering applications demand for biomaterials offering a substrate for cell adhesion, migration, and proliferation, while inferring suitable mechanical properties to the construct. In the present study, polyurethane (PU) foams were synthesized to develop a graded porous material-characterized by a dense shell and a porous core-for the treatment of oro-maxillary bone defects. Foam was synthesized via a one-pot reaction starting from a polyisocyanate and a biocompatible polyester diol, using water as a foaming agent. Different foaming conditions were examined, with the aim of creating a dense/porous functional graded material that would perform at the same time as an osteoconductive scaffold for bone defect regeneration and as a membrane-barrier to gingival tissue ingrowth. The obtained PU was characterized in terms of morphological and mechanical properties. Biocompatibility assessment was performed in combination with bone-marrow-derived human mesenchymal stromal cells (hBMSCs). Our findings confirm that the material is potentially suitable for guided bone regeneration applications. Copyright © 2015 Elsevier B.V. All rights reserved.

  3. TG-FTIR characterization of flame retardant polyurethane foams materials

    NASA Astrophysics Data System (ADS)

    Liu, W.; Tang, Y.; Li, F.; Ge, X. G.; Zhang, Z. J.

    2016-07-01

    Dimethyl methylphosphonate (DMMP) and trichloroethyl phosphtate (TCEP) have been used to enhance the flame retardancy of polyurethane foams materials (PUF). Flame retardancy and thermal degradation of PUF samples have been investigated by the LOI tests and thermal analysis. The results indicate that the excellent flame retardancy can be achieved due to the presence of the flame retardant system containing DMMP and TCEP. TG-FTIR reveals that the addition of DMMP/TCEP can not only improve the thermal stability of PUF samples but can also affect the gaseous phase at high temperature.

  4. Synthesis of Foam-Shaped Nanoporous Zeolite Material: A Simple Template-Based Method

    ERIC Educational Resources Information Center

    Saini, Vipin K.; Pires, Joao

    2012-01-01

    Nanoporous zeolite foam is an interesting crystalline material with an open-cell microcellular structure, similar to polyurethane foam (PUF). The aluminosilicate structure of this material has a large surface area, extended porosity, and mechanical strength. Owing to these properties, this material is suitable for industrial applications such as…

  5. Effects of ultrasound on polymeric foam porosity.

    PubMed

    Torres-Sanchez, C; Corney, J R

    2008-04-01

    A variety of materials require functionally graded cellular microstructures whose porosity is engineered to meet specific applications (e.g. mimic bone structure for orthopaedic applications; fulfil mechanical, thermal or acoustic constraints in structural foamed components, etc.). Although a huge variety of foams can be manufactured with homogenous porosity, there are no generic processes for controlling the distribution of porosity within the resulting matrix. Motivated by the desire to create a flexible process for engineering heterogeneous foams, the authors have investigated how ultrasound, applied during the formation of a polyurethane foam, affects its cellular structure. The experimental results demonstrated how the parameters of ultrasound exposure (i.e. frequency and applied power) influenced the volume and distribution of pores within the final polyurethane matrix: the data demonstrates that porosity (i.e. volume fraction) varies in direct proportion to both the acoustic pressure and frequency of the ultrasound signal. The effects of ultrasound on porosity demonstrated by this work offer the prospect of a manufacturing process that can adjust the cellular geometry of foam and hence ensure that the resulting characteristics match the functional requirements.

  6. Investigation and Development of Air Foam Cushioning

    DTIC Science & Technology

    1975-06-01

    n.c..#arr and lafenrffr or »lock numb«) CUSHIONING MATERIALS PACKAGING MATERIILS POLYURETHANE FOAM CUSHIONING SOLUTIONS ( AQUEOUS ) POLYMERS FOAMING ...Mixer. This froth foam could be produced by pour-in-place method or could be made into pre- formed and cut ribbon DD, ET» M73 EDITION OF I NOV SI IS...hours« The foam did not recover after the weight was removed« Work on the foaming of polyvinyl alcohol solution with an Oakes Mixer produced a spongy

  7. Effect of CNT as a Nucleating Agent on Cell Morphology and Thermal Insulation Property of the Rigid Polyurethane Foams.

    PubMed

    Ahn, WonSool; Lee, Joon-Man

    2015-11-01

    The effects of MWCNT on the cell sizes, cell uniformities, thermal conductivities, bulk densities, foaming kinetics, and compressive mechanical properties of the rigid PUFs were investigated. To obtain the better uniform dispersed state of MWCNT, grease-type master batch of MWCNT/surfactant was prepared by three-roll mill. Average cell size of the PUF samples decreased from 185.1 for the neat PUF to 162.9 μm for the sample of 0.01 phr of MWCNT concentration. Cell uniformity was also enhanced showing the standard cell-size deviation of 61.7 and 35.2, respectively. While the thermal conductivity of the neat PUF was 0.0222 W/m(o)K, that of the sample with 0.01 phr of MWCNT showed 0.0204 W/m(o)K, resulting 8.2% reduction of the thermal conductivity. Bulk density of the PUF samples was observed as nearly the same values as 30.0 ± 1.0 g/cm3 regardless of MWCNT. Temperature profiles during foaming process showed that an indirect indication of the nucleation effect of MWCNT for the PUF foaming system, showing faster and higher temperature rising with time. The compressive yield stress is nearly the same as 0.030 x 10(5) Pa regardless of MWCNT.

  8. 46 CFR 160.010-1 - Incorporation by reference.

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ... (Polystyrene Foam, Expanded Bead), (July 10, 1970), IBR approved for § 160.010-5 (“MIL-P-19644C”). (2) MIL-P-21929B, Military Specification, Plastic Material, Cellular Polyurethane, Foam-In-Place, Rigid (2 and 4...

  9. Elimination of toxicity from polyurethane foam plugs used for plant culture

    NASA Technical Reports Server (NTRS)

    Wheeler, R. M.; Schwartzkopf, S. H.; Tibbitts, T. W.; Langhans, R. W.

    1985-01-01

    Polyurethane foam plugs commonly are used as collars or supports to grow plants in solution culture. Despite their utility, these foam plugs can be quite toxic to plants, particularly to small seedlings. We have observed tissue injury in tests using plugs to support lettuce, red beet, and potato plants in solution culture. Typically, the injury is initiated on the hypocotyl or stem tissue in direct contact with the foam, and appears within 30 hr as a brownish discoloration on the tissue surface. This discoloration can be followed by complete collapse of affected tissue and eventual death of the seedling. When injury does not progress beyond surface browning, the seedling survives but growth is slowed. In this paper, we report on different treatments that can be used to remove the toxicity of these plugs so they can be used in plant research.

  10. The Development of Testing Methods for Characterizing Emissions and Sources of Exposures from Polyurethane Products

    EPA Science Inventory

    The relationship between onsite manufacture of spray polyurethane foam insulation (SPFI) and potential exposures is not well understood. Currently, no comprehensive standard test methods exist for characterizing and quantifying product emissions. Exposures to diisocyanate compoun...

  11. Thermal performance of aircraft polyurethane seat cushions

    NASA Technical Reports Server (NTRS)

    Kourtides, D. A.; Parker, J. A.

    1982-01-01

    Measurements were conducted on 7.6 x 7.6 cm samples of polyurethane seat cushion material in a modified National Bureau of Standards smoke density chamber to simulate real life conditions for an onboard aircraft fire or post-crash fire. In this study, a non-flaming heat radiation condition was simulated. Two aluminized polymeric fabrics (Norfab 11HT-26-A and Preox 1100-4) and one neoprene type material in two thicknesses (Vonar 2 and 3) were tested as heat blocking layers to protect the urethane foam from rapid heat degradation. Thermogravimetric analysis and differential scanning calorimetry were performed to characterize thermally the materials tested. It was found that Vonar 2 or 3 provided approximately equal thermal protection to F.R. urethane as the aluminized fabrics, but at a significant weight penalty. The efficiency of the foams to absorb heat per unit mass loss when protected with the heat blocking layer decreases in the heating range of 2.5-5.0 W/sq cm, but remains unchanged or slightly increases in the range of 5.0-7.5 W/sq cm. The results show that at all heat flux ranges tested the usage of a heat blocking layer in aircraft seats significantly improves their thermal performance.

  12. Sprayable Aerogel Bead Compositions With High Shear Flow Resistance and High Thermal Insulation Value

    NASA Technical Reports Server (NTRS)

    Ou, Danny; Trifu, Roxana; Caggiano, Gregory

    2013-01-01

    A sprayable aerogel insulation has been developed that has good mechanical integrity and lower thermal conductivity than incumbent polyurethane spray-on foam insulation, at similar or lower areal densities, to prevent insulation cracking and debonding in an effort to eliminate the generation of inflight debris. This new, lightweight aerogel under bead form can be used as insulation in various thermal management systems that require low mass and volume, such as cryogenic storage tanks, pipelines, space platforms, and launch vehicles.

  13. Influence of Tile Geometry on the Dynamic Fracture of Silicon Carbide (SiC)

    DTIC Science & Technology

    2014-03-01

    velocity was 440 ± 5.6 m/s. Two flash x-rays were set up above the shot line in front of the light gas gun to measure the velocity of the projectile...long, high-density polyurethane foam sabot. A sabot stripper on the muzzle of the gun disengaged the sabot from the sphere prior to velocity...the masses were consistent to achieve a constant velocity. The projectile traveled from the gun, through a break screen which triggered two flash x

  14. Experimental study of moisture uptake of polyurethane foam subjected to a heat sink below 30 K

    NASA Astrophysics Data System (ADS)

    Zhang, X. B.; Chen, J. Y.; Gan, Z. H.; Qiu, L. M.; Zhang, K. H.; Yang, R. P.; Ma, X. J.; Liu, Z. H.

    2014-01-01

    Rigid closed-cell foam is widely used to thermally insulate liquid hydrogen and oxygen tanks of space launch vehicles due to its lightweight, mechanical strength and thermal-insulating performance. Up to now, little information is available on the intrusion of moisture into the foam that subjects one side to liquid hydrogen temperatures and the other side to room temperatures and high relative humidity. A novel cryogenic moisture uptake apparatus has been designed and fabricated to measure the moisture uptake into the polyurethane foam. For safety and convenience, two identical single-stage pulse tube cryocoolers instead of liquid hydrogen are used to cool one side of the foam specimen to the lowest temperature of 26 K. Total of eight specimens in three groups, according to whether there is a butt-joint or weathering period, are tested respectively for both 5 h and 9 h. The additional weight due to moisture uptake of the foam for the 26 K cases is compared to previous measurements at 79 K. The results are instructive for the applications of foam to the insulation of liquid hydrogen tanks in space launch vehicles.

  15. A water blown urethane insulation for use in cryogenic environments

    NASA Technical Reports Server (NTRS)

    Blevins, Elana; Sharpe, Jon

    1995-01-01

    Thermal Protection Systems (TPS) of NASA's Space Shuttle External Tank include polyurethane and polyisocyanurate modified polyurethane foam insulations. These insulations, currently foamed with CFC 11 blowing agent, serve to maintain cryogenic propellant quality, maintain the external tank structural temperature limits, and minimize the formation of ice and frost that could potentially damage the ceramic insulation on the space shuttle orbiter. During flight the external tank insulations are exposed to mechanical, thermal and acoustical stresses. TPS must pass cryogenic flexure and substrate adhesion tests at -253 C, aerothermal and radiant heating tests at fluxes up to approximately 14 kilowatts per square meter, and thermal conductivity tests at cryogenic and elevated temperatures. Due to environmental concerns, the polyurethane insulation industry and the External Tank Project are tasked with replacing CFC 11. The flight qualification of foam insulations employing HCFC 141b as a foaming agent is currently in progress; HCFC 141b blown insulations are scheduled for production implementation in 1995. Realizing that the second generation HCFC blowing agents are an interim solution, the evaluation of third generation blowing agents with zero ozone depletion potential is underway. NASA's TPS Materials Research Laboratory is evaluating third generation blowing agents in cryogenic insulations for the External Tank; one option being investigated is the use of water as a foaming agent. A dimensionally stable insulation with low friability, good adhesion to cryogenic substrates, and acceptable thermal conductivity has been developed with low viscosity materials that are easily processed in molding applications. The development criteria, statistical experimental approach, and resulting foam properties will be presented.

  16. A pilot study comparing custom contoured and planar support surfaces for pressure ulcer risk over the heels for night time postural management using interface pressure mapping and discomfort scores.

    PubMed

    Hosking, J

    2017-08-01

    Custom contouring techniques are effective for reducing pressure ulcer risk in wheelchair seating. These techniques may assist the management of pressure ulcer risk during sleep for night time postural management. To investigate the effectiveness of custom contoured night time postural management components against planar support surfaces for pressure ulcer risk measures over the heels. Supine posture was captured from five healthy participants using vacuum consolidation and 3-dimensional laser scanning. Custom contoured abduction wedges were carved from polyurethane and chipped foams. Pressure mapping and the visual analog scale were used to evaluate the effectiveness of the contoured foams in reducing pressure and discomfort under the posterior heel against standard planar support surfaces. Custom contoured shapes significantly reduced interface pressures (p < 0.05) and discomfort scores (p < 0.05) when compared to planar support surfaces. Polyurethane foam was the most effective material but it did not differ significantly from chipped foam. Linear regression revealed a significant relationship between the Peak Pressure Index and discomfort scores (r = 0.997, p = 0.003). The findings of this pilot study suggested that custom contoured shapes were more effective than planar surfaces at reducing pressure ulcer risk surrogate measures over the posterior heels with polyurethane foam being the most effective material investigated. It is recommended that Evazote foam should not be used as a support surface material for night time postural management. Crown Copyright © 2017. Published by Elsevier Ltd. All rights reserved.

  17. Startup and long-term performance of biotrickling filters packed with polyurethane foam and poplar wood chips treating a mixture of ethylmercaptan, H2S, and NH3.

    PubMed

    Hernández, J; Lafuente, J; Prado, O J; Gabriel, D

    2013-04-01

    Treatment of a mixture of NH3, H2S, and ethylmercaptan (EM) was investigated for more than 15 months in two biotrickling filters packed with poplar wood chips and polyurethane foam. Inlet loads ranging from 5 to 10 g N-NH3 m-3 hr-1, from 5 to 16 g S-H2S m-3 hr-1, and from 0 to 5 g EM m-3 hr-1 were applied. During startup, the biotrickling filter packed with polyurethane foam was re-inoculated due to reduced biomass retention as well as a stronger effect of nitrogen compounds inhibition compared with the biotrickling filter packed with poplar wood. Accurate pH control between 7 and 7.5 favored pollutants abatement. In the long run, complete NH3 removal in the gas phase was achieved in both reactors, while H2S removal efficiencies exceeded 90%. EM abatement was significantly different in both reactors. A systematically lower elimination capacity was found in the polyurethane foam bioreactor. N fractions in the liquid phase proved that high nitrification rates were reached throughout steady-state operation in both bioreactors. CO2 production showed the extent of the organic packing material degradation, which allowed estimating its service lifetime in around 2 years. In the long run, the bioreactor packed with the organic packing material had a lower stability. However, an economic analysis indicated that poplar wood chips are a competitive alternative to inorganic packing materials in biotrickling filters. We provide new insights in the use of organic packing materials in biotrickling filters for the treatment of H2S, NH3, and mercaptans and compare them with polyurethane foam, a packing commonly used in biotrickling filters. We found interesting features related with the startup of the reactors and parameterized both the performance under steady-state conditions and the influence of the gas contact time. We provide relevant conclusions in the profitability of organic packing materials under a biotrickling filter configuration, which is infrequent but proven reliable from our research results. The report is useful to designers and users of this technology.

  18. 40 CFR Appendix Q to Subpart G of... - Unacceptable Substitutes Listed in the March 28, 2007 Final Rule, Effective May 29, 2007

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... commercial refrigeration—Rigid polyurethane sandwich panels. HCFC-22; HCFC-142b as substitutes for HCFC-141b... commercial refrigeration, and sandwich panels. —Rigid polyurethane slabstock and other foams. —Polystyrene...

  19. 40 CFR Appendix Q to Subpart G of... - Unacceptable Substitutes Listed in the March 28, 2007 Final Rule, Effective May 29, 2007

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... commercial refrigeration—Rigid polyurethane sandwich panels. HCFC-22; HCFC-142b as substitutes for HCFC-141b... commercial refrigeration, and sandwich panels. —Rigid polyurethane slabstock and other foams. —Polystyrene...

  20. 40 CFR Appendix Q to Subpart G of... - Unacceptable Substitutes Listed in the March 28, 2007 Final Rule, Effective May 29, 2007

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... commercial refrigeration—Rigid polyurethane sandwich panels. HCFC-22; HCFC-142b as substitutes for HCFC-141b... commercial refrigeration, and sandwich panels. —Rigid polyurethane slabstock and other foams. —Polystyrene...

  1. 40 CFR Appendix Q to Subpart G of... - Unacceptable Substitutes Listed in the March 28, 2007 Final Rule, Effective May 29, 2007

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... commercial refrigeration—Rigid polyurethane sandwich panels. HCFC-22; HCFC-142b as substitutes for HCFC-141b... commercial refrigeration, and sandwich panels. —Rigid polyurethane slabstock and other foams. —Polystyrene...

  2. 40 CFR Appendix Q to Subpart G of... - Unacceptable Substitutes Listed in the March 28, 2007 Final Rule, Effective May 29, 2007

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... commercial refrigeration—Rigid polyurethane sandwich panels. HCFC-22; HCFC-142b as substitutes for HCFC-141b... commercial refrigeration, and sandwich panels. —Rigid polyurethane slabstock and other foams. —Polystyrene...

  3. Enhanced degradation of pendimethalin by immobilized cells of Bacillus lehensis XJU.

    PubMed

    More, Veena S; Tallur, Preeti N; Niyonzima, Francois N; More, Sunil S

    2015-12-01

    A bacterium capable of degrading pendimethalin was isolated from the contaminated soil samples and identified as Bacillus lehensis XJU based on 16S rRNA gene sequence analysis. 6-Aminopendimethalin and 3,4-dimethyl 2,6-dinitroaniline were identified as the metabolites of pendimethalin degradation by the bacterium. The biodegradation of pendimethalin by freely suspended and the immobilized cells of B. lehensis on various matrices namely agar, alginate, polyacrylamide, and polyurethane foam was also investigated. The batch degradation rate was nearly the same for both free and immobilized cells in agar and alginate, whereas polyacrylamide- and PUF-immobilized cells degraded 93 and 100 of 0.1 % pendimethalin after 96 and 72 h, respectively. At higher concentration, the degradation rate of freely suspended cells decreased; whereas the same immobilized cells on polyurethane foam completely degraded 0.2 % pendimethalin within 96 h. The repeated batch degradation with the polyurethane foam-immobilized cells was reused for 35 cycles without losing the 0.1 % pendimethalin degrading ability. In contrast, agar-, alginate- and polyacrylamide-immobilized cells could be reused for 15, 18, and 25 cycles, respectively. When the pendimethalin concentration was increased to 0.2 %, the immobilized cells could be reused but the pendimethalin degradation rate was decreased. Polyurethane foam-immobilized cells exhibited better tolerance to pH and temperature alterations than freely suspended cells and could be stored for more than 3 months without losing pendimethalin degrading ability. The immobilization of cells capable of degrading pendimethalin may serve as an ideal technique for the complete degradation of the herbicide in the environment.

  4. Materials for foam type insulation

    NASA Technical Reports Server (NTRS)

    Hill, W. E.

    1971-01-01

    An internal foam fabrication is one of the concepts being considered for cryogenic insulation on the hydrogen tanks of the shuttle vehicle. The three-dimensional polyurethane used on the S-4 B tanks failed to meet the higher temperature requirements of the shuttle vehicle, however, and other foams under consideration include polyisocyanurates, polyphenylene oxides, polyimides, and polybenzimidazoles. Improved adhesive systems for attaching the foams to the interior tank wall are under study.

  5. 40 CFR 63.8800 - What performance tests and other procedures must I use to demonstrate compliance with the...

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... Emission Standards for Hazardous Air Pollutants: Flexible Polyurethane Foam Fabrication Operations Testing... paragraphs (e)(1) through (3) of this section. (1) If you use chlorinated fire retardant foams, determine the... retardant foams, determine the percent reduction of HCN to represent HAP emissions from the source. (2...

  6. 40 CFR Appendix M to Subpart G - Unacceptable Substitutes Listed in the September 30, 2004 Final Rule, Effective November 29, 2004

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... —Rigid polyurethane slabstock and other foams —Polystyrene extruded insulation boardstock and billet...—Unacceptable Substitutes Listed in the September 30, 2004 Final Rule, Effective November 29, 2004 Foam Blowing—Unacceptable Substitutes End-use Substitute Decision Comments All foam end-uses: HCFC-141b Unacceptable...

  7. 40 CFR 63.8800 - What performance tests and other procedures must I use to demonstrate compliance with the...

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... Emission Standards for Hazardous Air Pollutants: Flexible Polyurethane Foam Fabrication Operations Testing... paragraphs (e)(1) through (3) of this section. (1) If you use chlorinated fire retardant foams, determine the... retardant foams, determine the percent reduction of HCN to represent HAP emissions from the source. (2...

  8. 40 CFR 63.8800 - What performance tests and other procedures must I use to demonstrate compliance with the...

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... Emission Standards for Hazardous Air Pollutants: Flexible Polyurethane Foam Fabrication Operations Testing... paragraphs (e)(1) through (3) of this section. (1) If you use chlorinated fire retardant foams, determine the... retardant foams, determine the percent reduction of HCN to represent HAP emissions from the source. (2...

  9. 40 CFR Appendix M to Subpart G - Unacceptable Substitutes Listed in the September 30, 2004 Final Rule, Effective November 29, 2004

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... —Rigid polyurethane slabstock and other foams —Polystyrene extruded insulation boardstock and billet...—Unacceptable Substitutes Listed in the September 30, 2004 Final Rule, Effective November 29, 2004 Foam Blowing—Unacceptable Substitutes End-use Substitute Decision Comments All foam end-uses: HCFC-141b Unacceptable...

  10. 40 CFR 63.8800 - What performance tests and other procedures must I use to demonstrate compliance with the...

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... Emission Standards for Hazardous Air Pollutants: Flexible Polyurethane Foam Fabrication Operations Testing... paragraphs (e)(1) through (3) of this section. (1) If you use chlorinated fire retardant foams, determine the... retardant foams, determine the percent reduction of HCN to represent HAP emissions from the source. (2...

  11. 40 CFR Appendix M to Subpart G - Unacceptable Substitutes Listed in the September 30, 2004 Final Rule, Effective November 29, 2004

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... —Rigid polyurethane slabstock and other foams —Polystyrene extruded insulation boardstock and billet...—Unacceptable Substitutes Listed in the September 30, 2004 Final Rule, Effective November 29, 2004 Foam Blowing—Unacceptable Substitutes End-use Substitute Decision Comments All foam end-uses: HCFC-141b Unacceptable...

  12. 40 CFR 63.8800 - What performance tests and other procedures must I use to demonstrate compliance with the...

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... Emission Standards for Hazardous Air Pollutants: Flexible Polyurethane Foam Fabrication Operations Testing... paragraphs (e)(1) through (3) of this section. (1) If you use chlorinated fire retardant foams, determine the... retardant foams, determine the percent reduction of HCN to represent HAP emissions from the source. (2...

  13. H2S removal and bacterial structure along a full-scale biofilter bed packed with polyurethane foam in a landfill site.

    PubMed

    Li, Lin; Han, Yunping; Yan, Xu; Liu, Junxin

    2013-11-01

    Hydrogen sulfide accumulated under a cover film in a landfill site was treated for 7 months by a full-scale biofilter packed with polyurethane foam cubes. Sampling ports were set along the biofilter bed to investigate H2S removal and microbial characteristics in the biofilter. The H2S was removed effectively by the biofilter, and over 90% removal efficiency was achieved in steady state. Average elimination capacity of H2S was 2.21 g m(-3) h(-1) in lower part (LPB) and 0.41 g m(-3) h(-1) in upper part (UPB) of the biofilter. Most H2S was eliminated in LPB. H2S concentration varied along the polyurethane foam packed bed, the structure of the bacterial communities showed spatial variation in the biofilter, and H2S removal as well as products distribution changed accordingly. The introduction of odorants into the biofilter shifted the distribution of the existing microbial populations toward a specific culture that could metabolize the target odors. Copyright © 2013 Elsevier Ltd. All rights reserved.

  14. Rapid growing clay coatings to reduce the fire threat of furniture.

    PubMed

    Kim, Yeon Seok; Li, Yu-Chin; Pitts, William M; Werrel, Martin; Davis, Rick D

    2014-02-12

    Layer-by-layer (LbL) assembly coatings reduce the flammability of textiles and polyurethane foam but require extensive repetitive processing steps to produce the desired coating thickness and nanoparticle fire retardant content that translates into a fire retardant coating. Reported here is a new hybrid bi-layer (BL) approach to fabricate fire retardant coatings on polyurethane foam. Utilizing hydrogen bonding and electrostatic attraction along with the pH adjustment, a fast growing coating with significant fire retardant clay content was achieved. This hybrid BL coating exhibits significant fire performance improvement in both bench scale and real scale tests. Cone calorimetry bench scale tests show a 42% and 71% reduction in peak and average heat release rates, respectively. Real scale furniture mockups constructed using the hybrid LbL coating reduced the peak and average heat release rates by 53% and 63%, respectively. This is the first time that the fire safety in a real scale test has been reported for any LbL technology. This hybrid LbL coating is the fastest approach to develop an effective fire retardant coating for polyurethane foam.

  15. Influence of porosity and composition of supports on the methanogenic biofilm characteristics developed in a fixed bed anaerobic reactor.

    PubMed

    Picanço, A P; Vallero, M V; Gianotti, E P; Zaiat, M; Blundi, C E

    2001-01-01

    This paper reports on the influence of the material porosity on the anaerobic biomass adhesion on four different inert matrices: polyurethane foam, PVC, refractory brick and special ceramic. The biofilm development was performed in a fixed-bed anaerobic reactor containing all the support materials and fed with a synthetic wastewater containing protein, lipids and carbohydrates. The data obtained from microscopic analysis and kinetic assays indicated that the material porosity has a crucial importance in the retention of the anaerobic biomass. The polyurethane foam particles and the special ceramic were found to present better retentive properties than the PVC and the refractory brick. The large specific surface area, directly related to material porosity, is fundamental to provide a large amount of attached biomass. However, different supports can provide specific conditions for the adherence of distinct microorganism types. The microbiological exams revealed a distinction in the support colonization. A predominance of methanogenic archaeas resembling Methanosaeta was observed both in the refractory brick and the special ceramic. Methanosarcina-like microorganisms were predominant in the PVC and the polyurethane foam matrices.

  16. The insertion torque-depth curve integral as a measure of implant primary stability: An in vitro study on polyurethane foam blocks.

    PubMed

    Di Stefano, Danilo Alessio; Arosio, Paolo; Gastaldi, Giorgio; Gherlone, Enrico

    2017-07-08

    Recent research has shown that dynamic parameters correlate with insertion energy-that is, the total work needed to place an implant into its site-might convey more reliable information concerning immediate implant primary stability at insertion than the commonly used insertion torque (IT), the reverse torque (RT), or the implant stability quotient (ISQ). Yet knowledge on these dynamic parameters is still limited. The purpose of this in vitro study was to evaluate whether an energy-related parameter, the torque-depth curve integral (I), could be a reliable measure of primary stability. This was done by assessing if (I) measurement was operator-independent, by investigating its correlation with other known primary stability parameters (IT, RT, or ISQ) by quantifying the (I) average error and correlating (I), IT, RT, and ISQ variations with bone density. Five operators placed 200 implants in polyurethane foam blocks of different densities using a micromotor that calculated the (I) during implant placement. Primary implant stability was assessed by measuring the ISQ, IT, and RT. ANOVA tests were used to evaluate whether measurements were operator independent (P>.05 in all cases). A correlation analysis was performed between (I) and IT, ISQ, and RT. The (I) average error was calculated and compared with that of the other parameters by ANOVA. (I)-density, IT-density, ISQ-density, and RT-density plots were drawn, and their slopes were compared by ANCOVA. The (I) measurements were operator independent and correlated with IT, ISQ, and RT. The average error of these parameters was not significantly different (P>.05 in all cases). The (I)-density, IT-density, ISQ-density, and RT-density curves were linear in the 0.16 to 0.49 g/cm³ range, with the (I)-density curves having a significantly greater slope than those regarding the other parameters (P≤.001 in all cases). The torque-depth curve integral (I) provides a reliable assessment of primary stability and shows a greater sensitivity to density variations than other known primary stability parameters. Copyright © 2017 Editorial Council for the Journal of Prosthetic Dentistry. Published by Elsevier Inc. All rights reserved.

  17. Post-processing flame-retardant for polyurethane

    NASA Technical Reports Server (NTRS)

    Monaghan, P.; Sidman, K. R.

    1980-01-01

    Treatment of polyurethane form with elastomer formulation after processing makes foam fire resistant without compromising physical properties. In testing, once ignition source is removed, combustion stops. Treatment also prevents molten particle formation, generates no smoke or toxic gases in fire, and does not deteriorate under prolonged exposure to Sun.

  18. 40 CFR 63.8802 - What methods must I use to demonstrate compliance with the emission limitation for loop slitter...

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... Hazardous Air Pollutants: Flexible Polyurethane Foam Fabrication Operations Testing and Initial Compliance... for each material used in your foam fabrication operations, you must use one of the options in...

  19. 40 CFR 63.8802 - What methods must I use to demonstrate compliance with the emission limitation for loop slitter...

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... Hazardous Air Pollutants: Flexible Polyurethane Foam Fabrication Operations Testing and Initial Compliance... for each material used in your foam fabrication operations, you must use one of the options in...

  20. 40 CFR 63.8802 - What methods must I use to demonstrate compliance with the emission limitation for loop slitter...

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... Hazardous Air Pollutants: Flexible Polyurethane Foam Fabrication Operations Testing and Initial Compliance... for each material used in your foam fabrication operations, you must use one of the options in...

  1. 40 CFR 63.8802 - What methods must I use to demonstrate compliance with the emission limitation for loop slitter...

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... Hazardous Air Pollutants: Flexible Polyurethane Foam Fabrication Operations Testing and Initial Compliance... for each material used in your foam fabrication operations, you must use one of the options in...

  2. 40 CFR 63.8802 - What methods must I use to demonstrate compliance with the emission limitation for loop slitter...

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... Hazardous Air Pollutants: Flexible Polyurethane Foam Fabrication Operations Testing and Initial Compliance... for each material used in your foam fabrication operations, you must use one of the options in...

  3. RETENTION OF POLYURETHANE FOAM FRAGMENTS DURING VAC-THERAPY, A COMPLICATION TO BE CONSIDERED

    PubMed Central

    Dessy, L.A.; Serratore, F.; Corrias, F.; Parisi, P.; Mazzocchi, M.; Carlesimo, B.

    2013-01-01

    VAC-therapy is a closed-loop, non-invasive active system, characterised by a controlled and localized negative pressure applied on porous polyurethane absorbent foams. It promotes healing of acute and chronic wounds. Therapeutic effects of VAC-therapy have been proved and demonstrated, however this method can have some disadvantages. Even if it is a quite versatile device, only qualified medical/paramedical personnel should use it in order to avoid possible complications that can occur after an improper application. In this report, 11 cases of foam fragment retention within the wound are presented. This rare complication did not promote healing, but further hindered it. On the basis of our experience, it is mandatory to define indications, benefits and limitations of the VAC-therapy. PMID:23590296

  4. Effect of crumb-rubber particle size on mechanical response of polyurethane foam composites

    NASA Astrophysics Data System (ADS)

    Sanjay, Omer Sheik

    The compression properties of foam are governed by by three factors: i) cell edge bending ii) compression of cell fluid iii) membrane stresses in the cell faces. The effect of reinforcement, granular form of scrap tire rubber on contribution of each of these effects along with the physical properties of polyurethane foam is investigated. It is seen that the addition of crumb-rubber hinders the formation of cell membranes during the foaming process. Four different sizes of particles were chosen to closely study the effect of particle size on the physical properties of the foam composite. There is a definite pattern seen in each of the physical property of the composite with change in the particle size. Addition of crumb-rubber decreases the compressive strength but in turn increases the elastic modulus of the composite. The rubber particles act as the sites for stress concentration and hence the inclusion of rubber particles induces the capability to transfer the axial load laterally along the surface of the foam. Also, the filler material induces porosity into the foam, which is seen in the SEM images, and hence the addition of rubber particles induces brittleness, which makes the foam composites extensively applicable for structural application in sandwich components. The lightweight composite therefore is a potential substitute to the heavier metal foams and honeycombs as a protective layer.

  5. Mapping pocket gopher burrow systems with expanding polyurethane foam

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Felthauser, M.; McInroy, D.

    The impetus for this study arose from the need to isolate buried chemical and radioactive waste from burrowing animals. In a study of barrier materials that inhibit burrowing by pocket gophers (Thomomys spp.) into waste material, it was necessary to map tunnel systems as a function of depth and soil type. A method of mapping burrow systems was needed that would be economical, portable, useful in a variety of soil types, and give accurate, permanent records of burrow configurations. A method is described for injecting an expanding polyurethane foam to map burrow systems in situ.

  6. Ultrasonic measurements of the reflection coefficient at a water/polyurethane foam interface.

    PubMed

    Sagers, Jason D; Haberman, Michael R; Wilson, Preston S

    2013-09-01

    Measured ultrasonic reflection coefficients as a function of normal incidence angle are reported for several samples of polyurethane foam submerged in a water bath. Three reflection coefficient models are employed as needed in this analysis to approximate the measured data: (1) an infinite plane wave impinging on an elastic halfspace, (2) an infinite plane wave impinging on a single fluid layer overlying a fluid halfspace, and (3) a finite acoustic beam impinging on an elastic halfspace. The compressional wave speed in each sample is calculated by minimizing the sum of squared error (SSE) between the measured and modeled data.

  7. Polyurethane Foam-Filled Skull Replica of Craniosynostosis for Surgical Training.

    PubMed

    Jeong, Yeon Jin; Lee, Jun Yong

    2016-05-01

    Craniosynostosis has a relatively low incidence in the general population and its treatment requires cautious approaches. For these reasons, patients are usually referred to several specialists or a medical center. Therefore, most trainees and young surgeons do not have any chances to experience patients of craniosynostosis, but learn about it only from textbooks. And for a surgeon who tries to operate on a craniosynostosis patient, it is hard to make a proper preoperative plan.The authors suggest a polyurethane foam-filled skull replica of craniosynostosis for trainees that can also be used in planning a craniosynostosis operation.

  8. Investigation of Industrial Polyurethane Foams Modified with Antimicrobial Copper Nanoparticles

    PubMed Central

    Sportelli, Maria Chiara; Picca, Rosaria Anna; Ronco, Roberto; Bonerba, Elisabetta; Tantillo, Giuseppina; Pollini, Mauro; Sannino, Alessandro; Valentini, Antonio; Cataldi, Tommaso R.I.; Cioffi, Nicola

    2016-01-01

    Antimicrobial copper nanoparticles (CuNPs) were electrosynthetized and applied to the controlled impregnation of industrial polyurethane foams used as padding in the textile production or as filters for air conditioning systems. CuNP-modified materials were investigated and characterized morphologically and spectroscopically, by means of Transmission Electron Microscopy (TEM), and X-ray Photoelectron Spectroscopy (XPS). The release of copper ions in solution was studied by Electro-Thermal Atomic Absorption Spectroscopy (ETAAS). Finally, the antimicrobial activity of freshly prepared, as well as aged samples—stored for two months—was demonstrated towards different target microorganisms. PMID:28773665

  9. Application of a drainage film reduces fibroblast ingrowth into large-pored polyurethane foam during negative-pressure wound therapy in an in vitro model.

    PubMed

    Wiegand, Cornelia; Springer, Steffen; Abel, Martin; Wesarg, Falko; Ruth, Peter; Hipler, Uta-Christina

    2013-01-01

    Negative-pressure wound therapy (NPWT) is an advantageous treatment option in wound management to promote healing and reduce the risk of complications. NPWT is mainly carried out using open-cell polyurethane (PU) foams that stimulate granulation tissue formation. However, growth of wound bed tissue into foam material, leading to disruption of newly formed tissue upon dressing removal, has been observed. Consequently, it would be of clinical interest to preserve the positive effects of open-cell PU foams while avoiding cellular ingrowth. The study presented analyzed effects of NPWT using large-pored PU foam, fine-pored PU foam, and the combination of large-pored foam with drainage film on human dermal fibroblasts grown in a collagen matrix. The results showed no difference between the dressings in stimulating cellular migration during NPWT. However, when NPWT was applied using a large-pored PU foam, the fibroblasts continued to migrate into the dressing. This led to significant breaches in the cell layers upon removal of the samples after vacuum treatment. In contrast, cell migration stopped at the collagen matrix edge when fine-pored PU foam was used, as well as with the combination of PU foam and drainage film. In conclusion, placing a drainage film between collagen matrix and the large-pored PU foam dressing reduced the ingrowth of cells into the foam significantly. Moreover, positive effects on cellular migration were not affected, and the effect of the foam on tissue surface roughness in vitro was also reduced. © 2013 by the Wound Healing Society.

  10. Shock chemistry in SX358 foams

    NASA Astrophysics Data System (ADS)

    Maerzke, Katie; Coe, Joshua; Fredenburg, Anthony; Lang, John; Dattelbaum, Dana

    2017-06-01

    We have developed new equation of state models for SX358, a cross-linked PDMS polymer. Recent experiments on SX358 over a range of initial densities (0-65% porous) have yielded new data that allow for a more thorough calibration of the equations of state. SX358 chemically decomposes under shock compression, as evidenced by a cusp in the shock locus. We therefore treat this material using two equations of state, specifically a SESAME model for the unreacted material and a free energy minimization assuming full chemical and thermodynamic equilibrium for the decomposition products. The shock locus of porous SX358 is found to be ``anomalous'' in that the decomposition reaction causes a volume expansion, rather than a volume collapse. Similar behavior has been observed in other polymer foams, notably polyurethane.

  11. 40 CFR Table 3 to Subpart Mmmmm of... - Performance Test Requirements for New or Reconstructed Flame Lamination Affected Sources

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... Hazardous Air Pollutants: Flexible Polyurethane Foam Fabrication Operations Pt. 63, Subpt. MMMMM, Table 3... use chlorinated fire retardants in the laminated foam a. Method 26A in appendix A to part 60 of this... chlorinated fire retardants in the laminated foam a. A method approved by the Administrator i. Conduct the...

  12. 40 CFR Table 3 to Subpart Mmmmm of... - Performance Test Requirements for New or Reconstructed Flame Lamination Affected Sources

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... Hazardous Air Pollutants: Flexible Polyurethane Foam Fabrication Operations Pt. 63, Subpt. MMMMM, Table 3... use chlorinated fire retardants in the laminated foam a. Method 26A in appendix A to part 60 of this... chlorinated fire retardants in the laminated foam a. A method approved by the Administrator i. Conduct the...

  13. 40 CFR Table 3 to Subpart Mmmmm of... - Performance Test Requirements for New or Reconstructed Flame Lamination Affected Sources

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... Hazardous Air Pollutants: Flexible Polyurethane Foam Fabrication Operations Pt. 63, Subpt. MMMMM, Table 3... use chlorinated fire retardants in the laminated foam a. Method 26A in appendix A to part 60 of this... chlorinated fire retardants in the laminated foam a. A method approved by the Administrator i. Conduct the...

  14. 40 CFR Table 3 to Subpart Mmmmm of... - Performance Test Requirements for New or Reconstructed Flame Lamination Affected Sources

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... Hazardous Air Pollutants: Flexible Polyurethane Foam Fabrication Operations Pt. 63, Subpt. MMMMM, Table 3... use chlorinated fire retardants in the laminated foam a. Method 26A in appendix A to part 60 of this... chlorinated fire retardants in the laminated foam a. A method approved by the Administrator i. Conduct the...

  15. 40 CFR Table 3 to Subpart Mmmmm of... - Performance Test Requirements for New or Reconstructed Flame Lamination Affected Sources

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... Hazardous Air Pollutants: Flexible Polyurethane Foam Fabrication Operations Pt. 63, Subpt. MMMMM, Table 3... use chlorinated fire retardants in the laminated foam a. Method 26A in appendix A to part 60 of this... chlorinated fire retardants in the laminated foam a. A method approved by the Administrator i. Conduct the...

  16. "Grinding" cavities in polyurethane foam

    NASA Technical Reports Server (NTRS)

    Brower, J. R.; Davey, R. E.; Dixon, W. F.; Robb, P. H.; Zebus, P. P.

    1980-01-01

    Grinding tool installed on conventional milling machine cuts precise cavities in foam blocks. Method is well suited for prototype or midsize production runs and can be adapted to computer control for mass production. Method saves time and materials compared to bonding or hot wire techniques.

  17. Preparation and Structure Study of Water-Blown Polyurethane/RDX Gun Propellant Foams

    NASA Astrophysics Data System (ADS)

    Yang, Weitao; Yang, Jianxing; Zhao, Yuhua; Zhang, Yucheng

    2018-01-01

    Water-blown polyurethane/RDX foamed propellants were prepared using polyols and isocyanate as reactive binder system, hexogen (RDX) as energetic component, triethanolamine (TEA)/Ditin butyl dilaurate (T-12) as composite catalysts, and H2O as blowing agent. The influences of catalyst ratio, blowing agent amount, and solid filler content on the inner porous structure were studied. The results show that the balance of gel rate and cream rate that could be adjusted by catalyst ratio is a major influencing factor on porous structure of foamed propellants. When the ratio of TEA/T-12 was adjusted to 1/0.7, the morphology of the foamed propellant exhibited spherical and closed porous structure. Besides, when the water amount was increased from 0.1% to 0.5%, the pore size increased from 0.43 to 0.64 mm. The contents of RDX particles affected the cell nucleation and thus, the cell geometry. When the blowing agent amount was constant, the increased content of RDX filler led to a decreased pore size. The closed bomb test results showed that foamed propellants burned progressively in an in-depth combustion mode.

  18. Improving sound absorption property of polyurethane foams doped with natural fiber

    NASA Astrophysics Data System (ADS)

    Azahari, M. Shafiq M.; Rus, Anika Zafiah M.; Taufiq Zaliran, M.; Kormin, Shaharuddin

    2017-08-01

    This study investigates the acoustics behavior of wood fibre filler of Red Meranti - filled polyurethane foam as a sound absorbing material. Three different thicknesses have been selected which is 10 mm, 20 mm and 30 mm. By choosing percentage loading of Red Meranti (RM) wood fibre of 5%, 10%, 15% and 20% added with polymer foam is namely as polymer foam (PF) composites of PF5%, PF10%, PF15% and PF20%. The sound absorption coefficient (α) and pore structure of the foam samples have been examined by using Impedance Tube test and Scanning Electron Microscopy (SEM). The results revealed that the highest thickness of highest filler loading (PF20%) gives higher sound absorption coefficient (α). The absorption frequency level is observed at 0.9922 and 0.99889 which contributed from low and high frequency absorption level respectively. The smallest pores size structure was observed with highest filler loading of PF. The higher the thickness and the higher the percentage loading of wood filler gives smaller pore structure, consequently, increased the sound absorption coefficient level.

  19. Space Shuttle Stiffener Ring Foam Failure Analysis, a Non-Conventional Approach

    NASA Technical Reports Server (NTRS)

    Howard, Philip M.

    2015-01-01

    The Space Shuttle Program made use of the excellent properties of rigid polyurethane foam for cryogenic tank insulation and as structural protection on the solid rocket boosters. When foam applications de-bond, classical methods of failure analysis did not provide root cause of the failure of the foam. Realizing that foam is the ideal media to document and preserve its own mode of failure, thin sectioning was seen as a logical approach for foam failure analysis to observe the three dimensional morphology of the foam cells. The cell foam morphology provided a much greater understanding of the failure modes than previously achieved.

  20. A case for closed-loop recycling of post-consumer PET for automotive foams.

    PubMed

    Bedell, Matthew; Brown, Matthew; Kiziltas, Alper; Mielewski, Deborah; Mukerjee, Shakti; Tabor, Rick

    2018-01-01

    Striving to utilize sustainable material sources, polyester polyols made via glycolysis and esterification of recycled polyethylene terephthalate (rPET) scrap were used to synthesize flexible polyurethane (PU) foams typically found in automotive interior applications. The objective of this endeavor was to ascertain if a closed-loop model could be established with the discarded PET feedstock. In five separate formulations, up to 50% of the total polyol content (traditionally derived from petroleum-based feedstock) was replaced with the afore-mentioned sustainable recycled polyols. These foams underwent mechanical, thermal, morphological, and physical characterization testing to determine feasibility for use in an automotive interior. Young's modulus, tensile stress at maximum load, tear resistance, and compression modulus all increased by combined averages of 121%, 67%, 32%, and 150% over the control petroleum-based formulation, respectively, in foams possessing 50% rPET polyol content. Thermal stability also increased with sustainable polyol content; thermogravimetric analysis showed that 50% mass loss temperature increased by an average of 20 °C in foams containing 30% recycled polyol. Properties of density and SAG factor remained within 5% of the control petroleum-based reference foams. After comparing these findings to traditional polyols, a compelling argument can be made for the use of post-consumer automotive and industrial feedstocks in developing high-performing interior automotive PU foams. Copyright © 2017 Elsevier Ltd. All rights reserved.

  1. Synthesis of rigid polyurethane foams from phosphorylated biopolyols.

    PubMed

    de Haro, Juan Carlos; López-Pedrajas, Daniel; Pérez, Ángel; Rodríguez, Juan Francisco; Carmona, Manuel

    2017-08-18

    Renewable resources are playing a key role on the synthesis of biodegradable polyols. Moreover, the incorporation of covalently linked additives is increasing in importance in the polyurethane (PU) market. In this work, previously epoxidized grape seed oil and methyl oleate were transformed into phosphorylated biopolyols through an acid-catalyzed ring-opening hydrolysis in the presence of H 3 PO 4 . The formation of phosphate polyesters was confirmed by FT-IR and 31 P-NMR. However, the synthesis of a high-quality PU rigid foam was not possible using exclusively these polyols attending to their low hydroxyl value. In that way, different rigid PU foams were prepared from the phosphorylated biopolyols and the commercial polyol Alcupol R4520. It was observed that phosphorylated biopolyols can be incorporated up to a 57 wt.% in the PU synthesis without significant structural changes with respect to the commercial foam. Finally, thermogravimetric and EDAX analyses revealed an improvement of thermal stability by the formation of a protective phosphorocarbonaceous char layer.

  2. Evaluation of European District Heating Systems for Application to Army Installations in the United States

    DTIC Science & Technology

    2006-07-01

    pipes in hooded channels, and the steel insulated pipes are insulated with mineral wool . In the thermo- concrete laying system the insulation...depends on the type foam insulation used. • Class “A” steel carrier pipe with a mineral wool , foam glass, fiber glass, or calcium silicate insulation...with a mineral wool , foam glass, fiber glass, or calcium silicate insulation covered by a steel con- duit, which has a polyurethane foam insulation

  3. System Acquires Data On Reactivities Of Foams

    NASA Technical Reports Server (NTRS)

    Walls, Joe T.

    1994-01-01

    Data-acquisition and -plotting system, called DAPS(TM), developed enabling accurate and objective determination of physical properties related to reactivities of polyurethane and polyisocyanurate foams. Automated, computer-controlled test apparatus that acquires data on rates of rise, rise profiles, exothermic temperatures, and internal pressures of foams prepared from both manual and machine-mixed batches. Data used to determine minute differences between reaction kinetics and exothermic profiles of foam formulations, properties of end products which are statistically undifferentiated.

  4. A life-cycle comparison of several auxiliary blowing agents used for the manufacture of rigid polyurethane foam.

    PubMed

    Katz, Seton; Lindner, Angela S

    2003-04-01

    In a commitment to zero ozone depletion, the United Nations and the U.S. Environmental Protection Agency (EPA) have called for the phase-out of the manufacture and import of hydrochlorofluorocarbons (HCFCs), used as auxiliary blowing agents (ABAs) in the manufacture of polyurethane foams. As a result, more environmentally benign alternative ABAs are being sought by the foam-blowing industry. This study examined the life cycle of HCFC-22, hydrofluorocarbon-134a (HFC-134a), and cyclopentane, which are currently used or considered as potential alternative ABAs in the manufacture of rigid polyurethane foams that serve as insulation in a model North American refrigerator. The raw material extraction/refining, manufacturing, use, and disposal stages of the life cycle of each ABA were considered, and their resulting relative impacts on ozone depletion and global warming were compared. The manufacturing, use, and disposal stages were determined to affect ozone depletion and global warming to the largest extent, emphasizing the need for a greater focus on pollution prevention opportunities in these stages. The HFC-134a life cycle yields no impact on ozone depletion and a significantly decreased global warming impact compared with its predecessor, HCFC-22, and a tradeoff of slightly higher global warming impact and fewer added safety concerns compared with its more flammable counterpart, cyclopentane.

  5. Impact of the irregular microgeometry of polyurethane foam on the macroscopic acoustic behavior predicted by a unit-cell model.

    PubMed

    Doutres, O; Ouisse, M; Atalla, N; Ichchou, M

    2014-10-01

    This paper deals with the prediction of the macroscopic sound absorption behavior of highly porous polyurethane foams using two unit-cell microstructure-based models recently developed by Doutres, Atalla, and Dong [J. Appl. Phys. 110, 064901 (2011); J. Appl. Phys. 113, 054901 (2013)]. In these models, the porous material is idealized as a packing of a tetrakaidecahedra unit-cell representative of the disordered network that constitutes the porous frame. The non-acoustic parameters involved in the classical Johnson-Champoux-Allard model (i.e., porosity, airflow resistivity, tortuosity, etc.) are derived from characteristic properties of the unit-cell and semi-empirical relationships. A global sensitivity analysis is performed on these two models in order to investigate how the variability associated with the measured unit-cell characteristics affects the models outputs. This allows identification of the possible limitations of a unit-cell micro-macro approach due to microstructure irregularity. The sensitivity analysis mainly shows that for moderately and highly reticulated polyurethane foams, the strut length parameter is the key parameter since it greatly impacts three important non-acoustic parameters and causes large uncertainty on the sound absorption coefficient even if its measurement variability is moderate. For foams with a slight inhomogeneity and anisotropy, a micro-macro model associated to cell size measurements should be preferred.

  6. Isocyanate-Free Elastomers as Replacements for Isocyanate-Cured Polyurethanes (Briefing Charts)

    DTIC Science & Technology

    2015-08-20

    Polyurethanes (Briefing Charts) 5a. CONTRACT NUMBER In-House 5b. GRANT NUMBER 5c. PROGRAM ELEMENT NUMBER 6. AUTHOR(S) Josiah T. Reams, Andrew J...Standard Form 298 (Rev. 8-98) Prescribed by ANSI Std. 239.18 1 Isocyanate-Free Elastomers as Replacements for Isocyanate-cured Polyurethanes ...paints, foams , sealants, and adhesives that also represent a significant source of occupational health risk for DoD and DOE. DISTRIBUTION A:  Approved

  7. Mitigation of Oil in Water Column: Concept Development

    DTIC Science & Technology

    2016-06-01

    Argonne National Laboratory (ANL) proposes to use polyurethane foam , a commonly used material for many general purposes, as the material of choice to...adsorb submerged oil. Prior to use, the foam undergoes a series of chemical processes in order to render it oleophilic and thus more susceptible to...17. Key Words Adsorbent Foam , Adhesion, Microbubble, Sinking Oil, Submerged Oil, Oil Mitigation, Sorbent, Water Column 18. Distribution Statement

  8. Holding Cargo in Place With Foam

    NASA Technical Reports Server (NTRS)

    Fisher, T. T.

    1985-01-01

    Foam fills entire container to protect cargo from shock and vibration. Originally developed for stowing space debris and spent satellites in Space Shuttle for return to Earth, encapsulation concept suitable for preparing shipments carried by truck, boat, or airplane. Equipment automatically injects polyurethane foam into its interior to hold cargo securely in place. Container of rectangular or other cross section built to match shape of vehicle used.

  9. Thermographic observation of heat transport in solid foams

    NASA Astrophysics Data System (ADS)

    Netzelmann, U.; Abuhamad, M.; Walle, G.

    2005-06-01

    Heat transport in solid foams was studied by flash lamp heated dynamic thermography. For polyurethane foams, a movement of the peak temperature from the heated surface into the depth could be observed. This could be modelled by assuming a Beer optical absorber with non-adiabatic boundary. For large open pores, individual temperature-time curves were observed in the thermographic image. There is evidence for non-conductive heat transfer in the bulk of mixed-cell foams. In SiSiC ceramic foams, indications for sub-surface defects were detected.

  10. Fiberglass-Reinforced Rigid Polyurethane Expedient Pavement Subject to Simulated F-4 Aircraft Traffic.

    DTIC Science & Technology

    1980-05-01

    34 4,. * ., Table B-I. CPR-739 Rigid Polyurethane Foam Component Characteristics [ Cream Time, 120 sec; Rise Time, 13 sec; Cure Time, 24 hr at 750F...INC. E Colic Soil Tech Dept. Pennsauken. NJ SANDIA LABORATORIES Library Div., Livermore CA SCHUPACK ASSOC SO. NORWALK. CT (SCHUPACK) SHELL OIL CO

  11. Glycolysis recycling of rigid waste polyurethane foam from refrigerators.

    PubMed

    Zhu, P; Cao, Z B; Chen, Y; Zhang, X J; Qian, G R; Chu, Y L; Zhou, M

    2014-01-01

    Rapid growth of rigid waste polyurethane (WPUR) foam from refrigerators attracts the attention all over the world. In this study, glycolysis was chosen to treat WPUR from scrapped refrigerators collected in Shanghai, China. Glycolysis reagents and catalysts were selected. The results indicated that the glycolysis efficiency of ethylene glycol (EG) was higher than that of diethylene glycol, and the catalytic efficiency of alkali metal salts (NaOH) was more excellent than that of triethanolamine and organic salts of alkali metal (NaAc). When EG was 100%WPUR as a glycolysis reagent and NaOH was 1%WPUR as a catalyst at a constant temperature of 197.85°C for 2 h, the glycolysis product had the highest glycolysis conversion rate. In order to maximize the recycling of WPUR, regenerative Polyurethane was performed by adding 10% distilled mixed polyol, which conformed to the QB/T 26689-2011 requirements.

  12. Production of the biopesticide azadirachtin by hairy root cultivation of Azadirachta indica in liquid-phase bioreactors.

    PubMed

    Srivastava, Smita; Srivastava, Ashok K

    2013-11-01

    Batch cultivation of Azadirachta indica hairy roots was carried out in different liquid-phase bioreactor configurations (stirred-tank, bubble column, bubble column with polypropylene basket, and polyurethane foam disc as root supports) to investigate possible scale-up of the A. indica hairy root culture for in vitro production of the biopesticide azadirachtin. The hairy roots failed to grow in the conventional bioreactor designs (stirred tank and bubble column). However, modified bubble column reactor (with polyurethane foam as root support) configuration facilitated high-density culture of A. indica hairy roots with a biomass production of 9.2 g l(-1)dry weight and azadirachtin yield of 3.2 mg g(-1) leading to a volumetric productivity of azadirachtin as 1.14 mg l(-1) day(-1). The antifeedant activity in the hairy roots was also evaluated by no choice feeding tests with known concentrations of the hairy root powder and its solvent extract separately on the desert locust Schistocerca gregaria. The hairy root powder and its solvent extract demonstrated a high level of antifeedant activity (with an antifeedant index of 97 % at a concentration of 2 % w/v and 83 % at a concentration of 0.05 % (w/v), respectively, in ethanol).

  13. Occupational allergic and irritant contact dermatitis in workers exposed to polyurethane foam.

    PubMed

    Kieć-Świerczyńska, Marta; Swierczyńska-Machura, Dominika; Chomiczewska-Skóra, Dorota; Nowakowska-Świrta, Ewa; Kręcisz, Beata

    2014-04-01

    To evaluate sensitization to chemicals present in work environment after an outbreak of contact dermatitis in workers of vehicle equipment factory, exposed to polyurethane foam, based on 4,4'-diphenylmethane diisocyanate (MDI). From among 300 employees, 21 individuals reporting work-related skin and/or respiratory tract symptoms underwent clinical examination, patch testing, skin prick tests, spirometry and MDI sIgE measurement in serum. Patch tests included isocyanates series, selected rubber additives, metals, fragrances, preservatives, and an antiadhesive agent. Clinical examination revealed current eczema in the area of hands and/or forearms in 10 workers. Positive patch test reactions were found in 10 individuals, the most frequent to diaminodiphenylmethane and 4-phenylenediamine (7 persons). Reactions to an antiadhesive agent were assessed as irritant (5 workers). Except for sensitization to common aeroallergens, no significant abnormalities were found in the remaining tests. Occupational allergic contact dermatitis was diagnosed in 7 workers, irritant contact dermatitis in 10 and coexisiting allergic and irritant contact dermatitis in 3 workers. In workers manufacturing products from polyurethane foam, attention should be paid to the risk of developing contact dermatitis. Skin problems in our study group were attributable probably to insufficient protection of the skin.

  14. Vacuum Head Checks Foam/Substrate Bonds

    NASA Technical Reports Server (NTRS)

    Lloyd, James F.

    1989-01-01

    Electromechanical inspection system quickly gives measurements indicating adhesion, or lack thereof, between rigid polyurethane foam and aluminum substrate. Does not damage inspected article, easy to operate, and used to perform "go/no-go" evaluations or as supplement to conventional destructive pull-plug testing. Applies vacuum to small area of foam panel and measures distance through which foam pulled into vacuum. Probe head applied to specimen and evacuated through hose to controller/monitor unit. Digital voltmeter in unit reads deflection of LVDT probe head.

  15. Space Shuttle Stiffener Ring Foam Failure, a Non-Conventional Approach

    NASA Technical Reports Server (NTRS)

    Howard, Philip M.

    2007-01-01

    The Space Shuttle makes use of the excellent properties of rigid polyurethane foam for cryogenic tank insulation and as structural protection on the solid rocket boosters. When foam applications debond, classical methods of analysis do not always provide root cause of the failure of the foam. Realizing that foam is the ideal media to document and preserve its own mode of failure, thin sectioning was seen as a logical approach for foam failure analysis. Thin sectioning in two directions, both horizontal and vertical to the application, was chosen to observe the three dimensional morphology of the foam cells. The cell foam morphology provided a much greater understanding of the failure modes than previously achieved.

  16. Piloted Ignition to Flaming in Smoldering Fire-Retarded Polyurethane Foam

    NASA Technical Reports Server (NTRS)

    Putzeys, O.; Fernandez-Pello, A. C.; Urban, D. L.

    2007-01-01

    Experimental results are presented on the piloted transition from smoldering to flaming in the fire-retarded polyurethane foam Pyrell . The samples are small rectangular blocks with a square cross section, vertically placed in the wall of a vertical wind tunnel. Three of the vertical sample sides are insulated and the fourth side is exposed to an upward oxidizer flow of variable oxygen concentration and to a variable radiant heat flux. The gases emitted from the smoldering reaction pass upwards through a pilot, which consists of a coiled resistance heating wire. In order to compensate for the solid-phase and gas-phase effects of the fire retardants on the piloted transition from smoldering to flaming in Pyrell, it was necessary to assist the process by increasing the power supplied to the smolder igniter and the pilot (compared to that used for non-fire retarded foam). The experiments indicate that the piloted transition from smoldering to flaming occurs when the gaseous mixture at the pilot passes the lean flammability limit. It was found that increasing the oxygen concentration or the external heat flux increases the likelihood of a piloted transition from smoldering to flaming, and generally decreases the time delay to transition. The piloted transition to flaming is observed in oxygen concentrations of 23% and above in both low-density and high-density Pyrell. Comparisons with previous experiments show that the piloted transition from smoldering to flaming is possible under a wider range of external conditions (i.e. lower oxygen concentration) than the spontaneous transition from smoldering to flaming. The results show that the fire retardants in Pyrell are very effective in preventing the piloted transition to flaming in normal air, but Pyrell is susceptible to smoldering and the piloted transition to flaming in oxygen-enriched environments. Therefore, precautions should be taken in the design of applications of Pyrell in oxygen-enriched environments to reduce to the risk of a piloted transition to flaming.

  17. Enhanced low-temperature performance of a multicell LiSOC1sub2 battery

    NASA Astrophysics Data System (ADS)

    Street, H. K.

    A battery pack with a long life, low current, multitap power supply utilizing lithium thionyl chloride cells (LTC) is described. The battery was developed to provide power to a portable solid state recording accelerometer. The battery pack utilizes 10 Li/SOC12 type LTC-7PN keeper 2 cells. These cells are wired in a series parallel arrangement to provide two 6 volt outputs and two negative 3 volt outputs with a single common. Four 301 K ohm resistors are internally mounted and wired to permit an optional continuous 12 microampere current drain from the cells to eliminate voltage delay effects at very low temperatures. The prewired assembly is encapsulated, using Stepen Foam H-102N rigid polyurethane 2 lbs/ft(3) foam, molded to a density of 4 lbs/ft(3).

  18. 10 CFR 431.303 - Materials incorporated by reference.

    Code of Federal Regulations, 2014 CFR

    2014-01-01

    ... Transmission Properties by Means of the Heat Flow Meter Apparatus, approved May 1, 2004, IBR approved for § 431... insulation products for buildings—Factory made products of extruded polystyrene foam (XPS)—Specification..., (“DIN EN 13165”), Thermal insulation products for buildings—Factory made rigid polyurethane foam (PUR...

  19. 40 CFR 82.62 - Definitions.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... consisting of the following types of foam: (1) Closed cell rigid polyurethane foam; (2) Closed cell rigid... identification numbers: (1) A federal employer identification number; (2) A state sales tax exemption number; (3... means: (1) The seller of a product to a consumer or another distributor; or (2) A person who sells or...

  20. 45 CFR 671.12 - Waste disposal.

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ... chloride (PVC), polyurethane foam, polystyrene foam, rubber and lubricating oils, treated timbers and other... onto ice-free areas or into any fresh water system. (h) Open burning of wastes is prohibited at all... dispose of waste by open burning prior to March 1, 1994, allowance shall be made for the wind direction...

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