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1.
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   

2.
Rigid polyurethane (PU) foams were prepared using three North American seed oil starting materials. Polyol with terminal primary hydroxyl groups synthesized from canola oil by ozonolysis and hydrogenation based technology, commercially available soybean based polyol and crude castor oil were reacted with aromatic diphenylmethane diisocyanate to prepare the foams. Their physical and thermal properties were studied and compared using dynamic mechanical analysis and thermogravimetric analysis techniques, and their cellular structures were investigated by scanning electron microscope. The chemical diversity of the starting materials allowed the evaluation of the effect of dangling chain on the properties of the foams. The reactivity of soybean oil-derived polyols and of unrefined crude castor oil were found to be lower than that of the canola based polyol as shown by their processing parameters (cream, rising and gel times) and FTIR. Canola-PU foam demonstrated better compressive properties than Soybean-PU foam but less than Castor-PU foam. The differences in performance were found to be related to the differences in the number and position of OH-groups and dangling chains in the starting materials, and to the differences in cellular structure.  相似文献   

3.
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   

4.
Rigid urethane foams from hydroxymethylated linseed oil and polyol esters   总被引:6,自引:6,他引:0  
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   

5.
采用可再生的醇解蓖麻油多元醇为原料,与液溴进行加成反应制备溴化蓖麻油多元醇,通过红外光谱证实发生了溴化反应,并测定了产物粘度、羟值、酸值.通过发泡实验和氧指数、烟密度、水平燃烧等测试手段,考察了溴化蓖麻油基聚氨酯硬泡发泡参数和阻燃性质,并与工业级阻燃荆雅保RB-79制备的聚氨酯硬泡进行比较.结果表明,由溴化蓖麻油多元醇...  相似文献   

6.
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   

7.
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   

8.
This study investigated the physical properties of water‐blown rigid polyurethane (PU) foams made from VORANOL®490 (petroleum‐based polyether polyol) mixed with 0–50% high viscosity (13,000–31,000 cP at 22°C) soy‐polyols. The density of these foams decreased as the soy‐polyol percentage increased. The compressive strength decreased, decreased and then increased, or remained unchanged and then increased with increasing soy‐polyol percentage depending on the viscosity of the soy‐polyol. Foams made from high viscosity (21,000–31,000 cP) soy‐polyols exhibited similar or superior density‐compressive strength properties to the control foam made from 100% VORNAOL® 490. The thermal conductivity of foams containing soy‐polyols was slightly higher than the control foam. The maximal foaming temperatures of foams slightly decreased with increasing soy‐polyol percentage. Micrographs of foams showed that they had many cells in the shape of sphere or polyhedra. With increasing soy‐polyol percentage, the cell size decreased, and the cell number increased. Based on the analysis of isocyanate content and compressive strength of foams, it was concluded that rigid PU foams could be made by replacing 50% petroleum‐based polyol with a high viscosity soy‐polyol resulting in a 30% reduction in the isocyanate content. © 2012 Wiley Periodicals, Inc. J. Appl. Polym. Sci., 2013  相似文献   

9.
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   

10.
Glycolysis of poly(ethylene terephthalate) (PET) waste using different molar ratio of poly(ethylene glycol) (PEG400), was used to produce saturated hydroxyl-functional polyester polyols with castor oil (CO) by transesterification process. The waterborne polyurethane (WBPU) adhesives were synthesized from these saturated polyester polyols, isophorone diisocyanate (IPDI), dimethylolpropionic acid (DMPA), and hexamethoxymethyl melamine (HMMM) as cross-linking agent by a conventional prepolymer process. The glycolyzed polyols and polyester polyos formations were characterized using Fourier transform infrared spectroscopy (FTIR) and the molecular weights were determined using gel permeation chromatography (GPC). The cross-linking reaction between WBPU and HMMM was verified using FTIR and 1H NMR analysis. Thermal properties were investigated by thermogravimetric analysis (TG). Thermal stability of cross-linked WBPU significantly increased with decreasing castor oil content in the process of transesterification to obtain polyester polyol as a soft segment. The T15% and T50% (the temperature where 15 and 50% weight loss occurred) of WBPU increased with the decreasing of castor oil content in the obtained polyester polyols, caused by the steric hindrance of polyester polyol with higher castor oil content, in the process of cross-linking reactions with HMMM. The physico-mechanical properties of WBPU, such as hardness, adhesion test, and gloss of the dried films were also determined considering the effect of participation of HMMM in cross-linking reactions with polyurethane, on coating properties.  相似文献   

11.
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   

12.
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   

13.
Abstract

Kraft pine lignin was derivatized to a liquid polyol through oxypropylation. The resulting polyol was characterized by GPC, FT-IR, H1, C13, and P31 NMR and was compared to commercial polyols in view of the mechanical property of the corresponding rigid polyurethane foams for the first time. A series of lignin-based PU was synthesized by replacing varying weight percentages of the amount of sucrose polyol and glycerol polyol, two commonly used commercial polyols employed in the control foam preparation. All foams had a low density of ~30 Kg m?3 and showed typical linkages of PU in the FT-IR spectra. The diameter of closed-cells was ~650 μm for most of the foams as revealed by SEM images. The optimal compressive property of rigid PU foams was obtained using lignin polyol without the addition of any other commercial polyols primarily attributed to the rigidity of lignin aromatic structure and the high functionality of lignin hydroxyl groups.  相似文献   

14.
In this contribution, castor oil polyols with functionality of f = 2.7 and f = 2 are used as soft segments (SS) for synthesizing polyurethane elastomers (PUEs) without addition of petroleum-based polyol. The effect of molar ratio of castor oil polyols on structure and properties of PUEs has been investigated by Fourier transform infrared spectroscopy, differential scanning calorimetry, thermogravimetric analysis, dynamic mechanical analysis, X-ray diffraction, tensile, swelling, and water absorption tests. The results reveal that hydrogen bonding mainly exists in hard segments (HSs) and weakens with decreasing the molar percentage of castor oil polyol (f = 2.7) in SS. T g of SS decreases while T g of HS remains constant as molar percentage of castor oil polyol (f = 2.7) decreased. The initial degradation temperatures (T5%) are above 300 °C and independent of the molar ratio of castor oil polyols. However, the temperature at 50% weight loss (T50%) decreases significantly as molar percentage of castor oil polyol (f = 2.7) decreased. Moreover, PUEs exhibit very low water absorption rate, <1%, after immersing in water for 140 h at room temperature. © 2018 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2019 , 136, 47309.  相似文献   

15.
采用植物油多元醇、聚醚多元醇、异氰酸酯和发泡剂HCFC-141b等为主要原料,制备得到植物油聚氨酯泡沫塑料,探讨了植物油多元醇加入量对泡沫塑料压缩强度、屈服强度、弹性模量和动态粘弹性能影响.结果表明,随着植物油多元醇加入量增加,泡沫塑料的压缩强度和弯曲模量逐渐减小,弹性模量呈先缓慢上升后下降趋势.作为硬泡应用时,植物油多元醇添加量应小于20份,可提高阻尼性能.  相似文献   

16.
In this work, Nicotiana tabacum stalks and castor oil‐based polyol was synthesized via two step process. Preliminarily, stalks were liquefied using acid catalyst to procure glycol‐glycoside and the optimized conditions for liquefaction of N. tabacum stem's biomass was 150 °C temperature for 180 min time using PTSA as catalyst. Progressively, the glycol‐glycoside obtained from the former step was further reacted with castor oil in the presence of lithium hydroxide to get dark brown‐colored polyol with hydroxyl value was running in between 200 and 400 IOH. Glycol‐glycoside and polyols were characterized by chemical and instrumental methods. Further by employing open‐cup method involving the mixing of polyol and isocyanate adducts, the desired poly urethane rigid foam was obtained. The product was tested for their physical, mechanical, thermal, and morphological characteristics, while the thermal conductivity was in the range of 0.013 to 0.017 Kcal/mh °C. The performed study may yield high quality rigid or semi‐rigid polyurethane foams that are commonly used as insulation materials. © 2016 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2016 , 133, 43974.  相似文献   

17.
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   

18.
蓖麻油聚醚多元醇在聚氨酯软泡中的应用   总被引:1,自引:1,他引:0  
利用双金属催化剂(DMC)制备了相对分子质量在2000~5600之间的聚氨酯(PU)软泡用蓖麻油聚醚多元醇,并通过发泡实验与常用软泡聚醚多元醇H-330进行了性能比较。结果表明,相对分子质量2000的蓖麻油聚醚多元醇制备的泡沫拉伸强度、伸长率和压陷硬度等均优于H-330聚醚,表明蓖麻油聚醚多元醇完全可以取代普通聚醚多元醇用于普通软泡生产。  相似文献   

19.
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   

20.
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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