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Fifty vegetable oil‐based polyols were characterized in terms of their hydroxyl number and their potential of replacing up to 50% of the petroleum‐based polyol in waterborne rigid polyurethane foam applications was evaluated. Polyurethane foams were prepared by reacting isocyanates with polyols containing 50% of vegetable oil‐based polyols and 50% of petroleum‐based polyol and their thermal conductivity, density, and compressive strength were determined. The vegetable oil‐based polyols included epoxidized soybean oil reacted with acetol, commercial soybean oil polyols (soyoils), polyols derived from epoxidized soybean oil and diglycerides, etc. Most of the foams made with polyols containing 50% of vegetable oil‐based polyols were inferior to foams made from 100% petroleum‐based polyol. However, foams made with polyols containing 50% hydroxy soybean oil, epoxidized soybean oil reacted with acetol, and oxidized epoxidized diglyceride of soybean oil not only had superior thermal conductivity, but also better density and compressive strength properties than had foams made from 100% petroleum polyol. Although the epoxidized soybean oil did not have any hydroxyl functional group to react with isocyanate, when used in 50 : 50 blend with the petroleum‐based polyol the resulting polyurethane foams had density versus compressive properties similar to polyurethane foams made from 100% petroleum‐based polyol. The density and compressive strength of foams were affected by the hydroxyl number of polyols, but the thermal conductivity of foams was not. © 2007 Wiley Periodicals, Inc. J Appl Polym Sci 2007 相似文献
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Ruijun Gu Samir Konar Mohini Sain 《Journal of the American Oil Chemists' Society》2012,89(11):2103-2111
Polyol derived from soybean oil was made from crude soybean oil by epoxidization and hydroxylation. Soy-based polyurethane (PU) foams were prepared by the in-situ reaction of methylene diphenyl diisocyanate (MDI) polyurea prepolymer and soy-based polyol. A free-rise method was developed to prepare the sustainable PU foams for use in automotive and bedding cushions. In this study, three petroleum-based PU foams were compared with two soy-based PU foams in terms of their foam characterizations and properties. Soy-based PU foams were made with soy-based polyols with different hydroxyl values. Soy-based PU foams had higher T g (glass transition temperature) and worse cryogenic properties than petroleum-based PU foams. Bio-foams had lower thermal degradation temperatures in the urethane degradation due to natural molecular chains with lower thermal stability than petroleum skeletons. However, these foams had good thermal degradation at a high temperature stage because of MDI polyurea prepolymer, which had superior thermal stability than toluene diisocyanate adducts in petroleum-based PU foams. In addition, soy-based polyol, with high hydroxyl value, contributed PU foam with superior tensile and higher elongation, but lower compressive strength and modulus. Nonetheless, bio-foam made with high hydroxyl valued soy-based polyol had smaller and better distributed cell size than that using low hydroxyl soy-based polyol. Soy-based polyol with high hydroxyl value also contributed the bio-foam with thinner cell walls compared to that with low hydroxyl value, whereas, petroleum-based PU foams had no variations in cell thickness and cell distributions. 相似文献
4.
C. K. Lyon Vilma H. Garrett L. A. Goldblatt 《Journal of the American Oil Chemists' Society》1962,39(1):69-71
The preparation of solvent-blown rigid urethane foams from low cost castor oil-polyol mixtures was investigated. Solutions
of triisopropanolamine, and of mixtures of triisopropanolamine and triethanolamine in castor oil, were used as the polyol component of these foams. Foams were prepared by reacting these
polyol mixtures, in the presence of catalyst, surfactant, and trichlorofluoromethane, with prepolymers prepared from toluenediisocyanate
and certain polyether polyols or mixtures of these polyether polyols with castor oil. The effect of polyol and prepolymer
composition and blowing agent concentration on such foam properties as density and compressive strength was investigated.
The properties of the castor oil-based foams were comparable to those of foams obtained from more costly polyols.
Presented at the Spring Meeting of the American Oil Chemists' Society, St. Louis, Missouri, May 1–3, 1961.
A laboratory of the Western Utilization Researchand Development Division, Agricultural Research Service, U. S. Department
of Agriculture. 相似文献
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The focus of this work was to synthesize bio‐based polyurethane (PU) foams from soybean oil (SO). Different polyols from SO were produced as follows: soybean oil monoglyceride (SOMG), hydroxylated soybean oil (HSO), and soybean oil methanol polyol (SOMP). The SOMG was a mixture of 90.1% of monoglyceride, 1.3% of diglyceride, and 8.6% of glycerol. The effect of various variables (polyol reactivity, water content curing temperature, type of catalyst, isocyanate, and surfactant) on the foam structure and properties were analyzed. SOMG had the highest reactivity because it was the only polyol‐containing primary hydroxyl (? OH) groups in addition to a secondary ? OH group. PU foams made with SOMG and synthetic polyol contained small uniform cells, whereas the other SO polyols produced foams with a mixture of larger and less uniform cells. The type of isocyanate also had an influence on the morphology, especially on the type of cells produced. The foam structure was found to be affected by the water and catalyst content, which controlled the foam density and the cure rate of the PU polymer. We observed that the glass transition (Tg) increased with the OH value and the type of diisocyanate. Also, we found that the degree of solvent swelling (DS) decreased as Tg increased with crosslink density. These results are consistent with the Twinkling Fractal Theory of Tg. © 2009 Wiley Periodicals, Inc. J Appl Polym Sci, 2009 相似文献
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New polyols of high hydroxyl content and reactivity were made from linseed and soybean oils and acids by catalytic carboxylation
followed by reaction with diethanolamine. Urethane foams made with these diethanolamides were stronger than those made with
castor oil at equivalent polyol wt. Because of their higher hydroxyl content, a larger amount of diethanolamides could be
incorporated in foam formulations than is possible with castor oil. The rigid urethane foams prepared with the new polyols
meet the requirements of commercial products with respect to density, compressive strength, and dimensional stability.
National Flaxseed Processors Association Fellow, 1969–1973. Present address: Avery Products, Technical Center, 325 North Altadena
Dr., Pasadena, CA 91107. 相似文献
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Indrajeet Singh Sushanta K. Samal Smita Mohanty Sanjay K. Nayak 《European Journal of Lipid Science and Technology》2020,122(3)
Polyurethane foams (PUFs) are widely used materials because of their wide range of applications, particularly, thermal and sound insulation, mattresses, furniture, construction, cushioning, packaging, transportation of goods, etc. Recently, commercial PUF products fabricated from plant oil (PO)‐based polyols have gained increasing popularity, because of their low cost and eco‐friendly nature in comparison to petroleum‐based PUF. To date, insufficient reviews have been reported in the area of modification of plant oils for synthesizing polyol for foam synthesis. Due to abundant availability, low‐cost, and renewable nature of plant oils, they are being used as precursors for modern polyurethane industry use. There is a need for versatile and economical methods for conversion of plant oils such as castor oil (CO) and soybean oil (SO) into useful polyols for industry use. This review is an overview of the most recent advanced methods for the conversion of plant oils into polyol and further utilization of it for commercial PUF products. Since the last decade, many researchers have shown that plant‐polyol‐derived PUF can compete with conventional PUF. Practical Applications: Practical applications of the PO‐based polyurethane foams include thermal insulation, sound insulation, packaging, and waste water treatment. 相似文献
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C. K. Lyon Vilma H. Garrett L. A. Goldblatt 《Journal of the American Oil Chemists' Society》1964,41(1):23-25
Solvent-blown rigid urethane foams prepared from a low-cost polyol mixture composed of raw castor oil and triisopropanolamine
have been described. Foams with higher compressive strengths can be obtained by substituting oxidized (blown) castor oil for
the raw castor oil in formulations of this type.
The properties of rigid foams prepared from several commercial blown castor oils are described. The properties of these foams
are correlated with the degree of oxidation of the blown oils used, as indicated by their oxygen content, density, viscosity,
and refractive index. Removal of acid from blown oils having high acid values has no significant effect on the compressive
strength of foams prepared from these oils.
When blown castor oil is used instead of raw castor oil, less isocyanate is required to produce a urethane foam of specified
density and compressive strength.
Presented at the AOCS meeting in Toronto, Canada, 1962.
A laboratory of the W. Utiliz. Res. & Dev. Div., ARS, U.S.D.A. 相似文献
9.
C. K. Lyon Vilma H. Garrett Leo A. Goldblatt 《Journal of the American Oil Chemists' Society》1961,38(5):262-266
The preparation of trichlorofluoromethane-blown rigid urethane foams using toluenediisocyanate and castor oil-derived polyols
was investigated. The castor-based polyols included castor oil, hydroxylated castor oil, technical glycerol-, penta-erythritol-,
and sorbitol monoricinoleates, and N,N-bis(2-hydroxyethyl) ricinoleamide.
The last of these yielded the best foams when used as the sole polyol component added to the prepolymer. However better foams
were obtained by using, as the polyol component, a mixture of a castor oil-derived polyol and a lower-molecular-weight polyol
with a higher hydroxyl content. These polyol mixtures yielded more highly cross-linked polymers and hence foams with higher
compressive strengths and less tendency to shrink after foaming.
The effect of catalyst, silicone surfactant, and trichlorofluoromethane content was also investigated. An empirical relationship
between density and compressive strength in a given foam system was derived.
Presented at the fall meeting, American Oil Chemists' Society, New York, October 17–19, 1960.
A laboratory of the Western Utilization Research and Development Division. Agricultural Research Service, U.S. Department
of Agriculture. 相似文献
10.
Aruna Palanisamy 《Polymer Composites》2013,34(8):1306-1312
The present work deals with the development of polyurethane–clay nanocomposite foams by replacing part of the synthetic polyol with castor oil derivative. Hydroxylated castor oil was converted into diethanol amide by transamidation and the resulting polyol was formulated into water‐blown foams. Modified montmorillonite clay was used as nanofiller in different amounts viz. 0.5%, 1.0%, 2.0%, and 5.0% by total weight of the foam formulation. Rheological measurements on the polyol–clay mixtures indicated that up to 1% clay loading there is no significant change in the viscosity with shear rate and beyond 2%, shear thinning occurred. X‐ray diffraction studies further substantiated these results. The effect of the modified clay on the density, mechanical properties such as compression strength, compression modulus, and microstructure of the foams were investigated. The filler thus added had a reinforcing effect on the foam as observed in the density and compression strength measurements. Differential scanning calorimetric studies on Tg and dynamic mechanical analyses on the modulus clearly indicated that 1% clay loading and above led to exfoliation and plasticizing effect. Exfoliated nanocomposites in compositions containing 1% clay and more yielded a much higher nucleation rate than intercalated ones leading to reduced cell size as observed by optical and scanning electron microscopy. Thus, castor oil, which is readily available, relatively inexpensive, and environmentally benign nonedible oil, has been successfully used to prepare filled semirigid foams which can find application in insulation and packing. POLYM. COMPOS. 34:1306–1312, 2013. © 2013 Society of Plastics Engineers 相似文献
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D. A. Yeadon A. R. Markezich L. A. Goldblatt 《Journal of the American Oil Chemists' Society》1959,36(11):541-545
Summary The preparation and properties of two series of castor oil urethane foams, one from castor oil and the other from elaidinized
castor oil, were investigated. The first series of foams was made from prepolymers containing 60% of castor oil prepared at
increasing temperature levels to vary the degree of crosslinking in the final foams. These foams had lower tensile strengths
than observed for a previously prepared foam of 60% castor oil and did not show significant differences in water resistance
as crosslinking varied. They were increased nearly 100% in compressive strength with increased crosslinking and had very good
shrinkage characteristics as values of only 1 to 2% were obtained.
A second series of foams was prepared from 50, 60, 70, and 80% of elaidinized castor oil to compare with foams from a similar
series from castor oil. This series of foams of 50 to 80% elaidinized castor oil contents was similar in density (1.7 to 6.7
lbs./cu. ft.), had improved shrinkage characteristics (11, 1, 3, and 4%, respectively), showed increased compressive and tensile
strengths (up to 12.1 p.s.i. at 50% compression modulus and 34.7 p.s.i. ultimate tensile for the 60% foam formulation), and
had better water-resistance properties (411 to 155%vs. 515 to 170% water absorption) than the analogous foams from castor oil. In general, humid aging only slightly affected the
values obtained for the foams and was significant in only a few instances,e.g., decreased tensile in the elaidinized castor oil series.
Thus increasing crosslinks in the foam apparently did not improve water resistance but did improve shrinkage characteristics
in addition to some increased strength properties, as would be anticipated. Foams from elaidinized castor oil, while similar
in density and foaming characteristics to analogous foams from castor oil, exhibited less shrinkage and improved water-resistance.
Presented at the 50th Annual Meeting of the American Oil Chemists' Society, New Orleans, La., April 20–22, 1959.
Ono of the laboratories of the Southern Utilization Research and Development Division, Agricultural Research Service, U. S.
Department of Agriculture. 相似文献
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The modulus development of reacting polyurethane foams from modified soy oil (soy polyol) was studied. The reaction and buildup of rheological properties were monitored using vane geometry in a strain‐controlled rheometer. Normal force exerted on the vanes by the expanding foam was measured as a function of time to study the phenomenon of cell opening. The effect of foam ingredients and process parameters on the modulus development was investigated. The morphology of the cured foam was studied using scanning electron microscope (SEM). Experiments were carried out to elucidate the effect of water and addition of petroleum‐based polyol on the modulus development of the reacting foam and the morphology of the cured product. The effect of frequency and thermal history on the modulus development of the reacting foam was also studied. Ozonolysis of soybean oil was carried out to study the effect of adding OH groups on the modulus development during the foaming reaction. Four stages of modulus development, similar to those observed for synthetic polyol (voranol, Aldrich Chemicals) foams, were observed. Increase in water content led to an earlier stiffening of the polymer and a higher modulus. Addition of voranol in soy polyol reduced the liquid foam plateau and significantly reduced the reaction time. Ozonolysis of soy oil led to an earlier phase separation as compared with foams from soy polyol. The temperature at which the foaming reaction takes place dominated the rate of modulus buildup. Higher texture (urea aggregates) and an increase in the cell size were observed with an increase in water content for soy polyol foams. Addition of voranol increased the number of open cells. Polym. Eng. Sci. 44:1977–1986, 2004. © 2004 Society of Plastics Engineers. 相似文献
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蓖麻油基聚酯多元醇的制备及表征 总被引:1,自引:0,他引:1
以可再生资源蓖麻油、苯酐和小分子醇为原料,钛酸正丁酯为催化剂,经酯化、缩聚合成蓖麻油基聚酯多元醇,考察了反应时间对聚酯多元醇酸值的影响以及不同官能度的小分子醇对醇解蓖麻油结构和羟值的影响。采用红外光谱仪(FT—IR)、凝胶色谱(GPC)、热失重仪(TGA)对醇解蓖麻油、蓖麻油基聚酯多元醇的相对分子质量、热稳定性进行了表征。结果表明,随着小分子醇官能度的增加,醇解体系中单酯和二酯含量明显减少,转化率也相应减小;甘油醇解蓖麻油和蓖麻油基聚酯多元醇较普通聚醚多元醇635具有更高的热稳定性。 相似文献
15.
Zoran S. Petrović Xianmei Wan Olivera Bilić Alisa Zlatanić Jian Hong Ivan Javni Mihail Ionescu Jelena Milić Darin Degruson 《Journal of the American Oil Chemists' Society》2013,90(7):1073-1078
The composition of crude algal oil was analyzed and determined by several methods. Oil was converted to polyols by ozonolysis, epoxidation, and hydroformylation. Ozonolysis gave a polyol with lighter color but a low OH number and was unsuitable for polyurethane applications. Epoxidation also improved the color and gave a polyol with an OH number around 150 mg KOH/g, which with diphenylmethane diisocyanate gave a homogeneous, rubbery, transparent sheet. Desirable rigid foams were prepared with the addition of water to the formulation. Hydroformylation was carried out successfully giving an OH number of about 150 mg KOH/g, but the polyol was black. Casting the polyurethane sheet was difficult due to the very high reactivity of the polyol. Polyurethane foam of lower quality than from epoxidation polyol was obtained. More work on optimization of the foaming system would improve the foam. Crude algal oil is a viable starting material for the production of polyols. Better results would be obtained from refined algal oils. 相似文献
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Polyurethane (PU) flexible foams were synthesized by substituting a portion of base polyether polyol with soybean oil-derived polyol (SBOP) as well as well-known substituent: crosslinker polyol and styrene acrylonitrile (SAN) copolymer-filled polyol. Increases in compression modulus were observed in all substituted foams and the most substantial increase was found in the 30% SBOP-substituted sample. Scanning electron microscopy (SEM) was used to examine cellular structure, in particular cell size. Polymer phase morphology, i.e., interdomain spacing and microphase separation, was studied using small-angle X-ray scattering (SAXS) and atomic force microscopy (AFM). Hydrogen bonding was investigated via Fourier transform infrared (FTIR) spectroscopy. Thermal and mechanical behaviors of foams were examined using dynamic mechanical analysis (DMA) and differential scanning calorimetry (DSC). Compression properties were tested and compared via a 65% indentation force deflection (IFD) test. It was found that substituting SAN-filled polyol slightly reduced foam cell size and had no effect on polymer phase morphology. Crosslinker and SBOP polyols, on the other hand, had appreciable influence on polymer phase morphology. Crosslinker polyol disrupted hydrogen bonding between hard segments and was mixed with hard domains. SBOP polyol reduced hard domain size and soft domain fraction, and showed a broad distribution of interdomain spacings. Compression modulus increases in foams correlated well with shear modulus by DMA and could be associated with the polymer phase morphology changes. 相似文献
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T. H. Khoe F. H. Otey E. N. Frankel 《Journal of the American Oil Chemists' Society》1972,49(11):615-618
Rigid urethane foams were prepared from hydroxymethylated linseed oil and its esters of glycerol, trimethylolpropane and pentaerythritol.
These polyols were made by selective hydroformylation with a rhodium-triphenylphosphine catalyst followed by catalytic hydrogenation
with Raney nickel. Although the hydroxymethylated linseed monoglyceride by itself yielded a satisfactory foam, better foams
were made from all hydroxymethylated linseed derivatives when blended with a low-molecular weight commercial polyol. Linseed-derived
foams were compared with foams from equivalent formulations of hydroxymethylated monoolein and castor oil. Hydroxymethylated
products yielded polyurethane foams meeting the requirements of commercial products with respect to density, compressive strength
and dimensional stability.
National Flaxseed Processors Association Fellow.
N. Market. Nutr. Res. Div., ARS, USDA. 相似文献
20.
Castor oil polyol (COP) having a hydroxyl number of 400?mg?KOH/g was prepared through the transesterification reaction of castor oil with glycerol. The effect of reaction temperature on the composition, hydroxyl number and viscosity of the COP products was studied. A series of rigid polyurethane foams were synthesised using the mixtures comprising COP and a petroleum-based polyol with various proportions as polyol component. It was found that the foaming rate, compressive strength and dimensional stability and morphology of resulting foams were dominated by the foam formulation, in a more accurate way, COP content in the polyol mixtures. The combination of expandable graphite and dimethyl methyl phosphonate exhibited stronger flame retardant function which was ascribed to the synergistic effect associated with the simultaneous presence of the two additives. An improvement in thermal stability was observed due to the inclusion of the flame retardants. 相似文献