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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.
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   

3.
蓖麻油型单组分聚氨酯发泡胶的制备   总被引:2,自引:0,他引:2  
从赫雷  林中祥 《粘接》2009,(6):55-59
研究了以蓖麻油、聚醚多元醇、聚酯多元醇、PAPI为原料合成系列发泡单组分聚氯酯胶粘剂的工艺,研究了各因素对预聚体的合成、产品性能及贮存稳定性的影响。结果表明,异氰酸酯指数为28~30,蓖麻油为多元醇总质量的40%,预聚催化剂为T-12,固化催化剂为吗啉类和LX-1,溶剂为乙酸乙酯和二氧甲烷,在70-80℃下反应3h,得到符合建材工业要求的产品。  相似文献   

4.
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   

5.
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   

6.
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   

7.
以聚醚多元醇、蓖麻油、TDI、MDI等为主要原料合成了异氰酸酯基(-NCO)封端的预聚物,以MOCA、聚醚多元醇、蓖麻油等为固化剂组成的双组分聚氨酯修补剂。优化后的配方断裂伸长率大于200%,拉伸强度达5.6MPa。对橡胶的粘接强度大于其本体强度。  相似文献   

8.
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   

9.
阎儒峰  韩国斌 《塑料工业》1992,(5):26-28,18
进行了以蓖麻油、聚醚混合多元醇为原料,制取聚氨酯软质泡沫塑料的改性试验,探讨了原料配比、TDI指数等各种因素对软泡密度及物理机械性能的影响,提出了优良配方范围,为工业生产提供理论参数,是低成本软泡开发及蓖麻油多元醇综合利用的新途径。  相似文献   

10.
Alewife fish oil was hydroxylated by performic, peracetic and pertungstic acid methods. Products were compared with respect to yield, free acid, hydroxyl number, saponification value and peroxide value. Fish oils oxidized with performic acid resulted in high yields (83% to 95%), low acid values (0.12 to 0.19), high hydroxy (142 to 245) and saponification (247 to 271) numbers, and relatively low peroxide values (72 to 266). Performic acid hydroxylated alewife and menhaden oils were used to prepare urethane foams. These foams exhibited characteristic low compressive strengths at 10% deflection (6.4 to 9.5 psi), low density (1.45 to 1.65 pcf), high porosity (0.7 to 1.7% closed cells) and high water absorption compared to a conventional polyether urethane foam. Performic acid hydroxylated alewife oil was further refined, using cation and anion exchange resins, for use in the preparation of urethane elastomers. These polymers generally exhibited higher tensile and Graves tear strengths than a comparable castor oil elastomer used as a control. though dielectric strengths were similar for both fish oil and castor oil elastomers, tensile elongation at break point was greater for the castor oil elastomers. When the isocyanate index of the fish oil elastomers was increased from 105 to 156, the Graves tear strength exhibited the greatest change.  相似文献   

11.
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   

12.
Liquid polyols have been prepared from epoxidized glyceryl trioleate, glyceryl monooleate, lard oil, neatsfoot oil, and soybean oil by hydration with 24% fluoboric acid. Upon adjustment of the equivalent weight to 100 with triisopropanolamine, the polyols were foamed by reaction with a prepolymer made from oxypropylated sorbitol and tolylene diisocyanate. The resulting rigid foams had densities between 1.66 and 2.34 lbs/ft3 and compressive strengths ranging from 23 to 39 psi (10% compression). The same polyols were used in one-step systems with PAPI as the isocyanate. In general, foam properties were comparable with those obtained from the prepolymer systems. Presented at the AOCS Meeting, New Orleans, 1967. E. Utiliz. Res. Dev. Div., ARS, USDA.  相似文献   

13.
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   

14.
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   

15.
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   

16.
The development of vegetable oil-based polymers was particularly suitable for the era of increasingly scarce petroleum. Self-colored castor oil-based waterborne polyurethanes (PUs) were successfully synthesized based on castor oil and 1-amino-4-hydroxy-2-(6-hydroxyhexyl) anthraquinone (DR) as polyols. The UV–Vis spectrum showed that the addition of carboxylic acid groups make the spectrum of the PU produce the hyperchromic effect under alkaline conditions. Castor oil-based waterborne colored PUs possessed excellent stability under weak alkaline conditions. The connection of castor oil caused the PU to constitute soft polymer networks. PU coatings on cotton fabrics possessed excellent color properties. The urethane groups in the PUs formed hydrogen bonds with the hydroxyl groups on the cotton fibers and the polymer network structure formed by the PU coating itself made the color fastness of the cotton coatings reached grade 5. With the increase of castor oil content, the degradation rate of castor oil-based waterborne colored PU increased from 3.45% to 3.65%. This work provides a way to impart excellent color properties and fastness to PU coatings by inserting dye molecules and vegetable oils into the PU macromolecular chain.  相似文献   

17.
Foam stability and segmented polymeric phase morphology of polyurethane foams synthesized partially and completely from castor oil are investigated. Preliminary analysis of the impact of alterations in the polymeric phase on macroscopic stress dissipation in foams is also carried out. The stability and morphology show unique trends depending on the concentration of castor oil used in foam synthesis. While low and intermediate concentrations of castor oil does not significantly affect the foaming process; at high concentrations, the volumetrically expanding liquid matrix remains in a nonequilibrium state during the entire foaming period, resulting in significant foam decay from top. This increases the final foam cell density and decreases the plateau border thickness at bottom. In the polymeric phase of castor oil based foams, the fraction of monodentate urea increases at the cost of non‐hydrogen bonded urea. These monodentate urea domains undergo flocculation in foams synthesized completely from castor oil, thus prominently modifying the segmented morphology. The glass transition temperature of soft segments of partially substituted foams shows moderate increase, with indications of phase mixing between the polyether and castor oil generated urethane domains. Foams synthesized entirely from castor oil have significant sol fraction due to unreacted oligomers. The microscopic alterations in polymeric phase reduce the elastic recovery of partially substituted castor oil foams compared to its viscous dissipation under an applied stress. © 2014 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2014 , 131, 40668.  相似文献   

18.
以聚醚多元醇、聚酯多元醇和蓖麻油为混合多元醇,以改性MDI(4,4′-二苯基甲烷二异氰酸酯)及PAPI(多亚甲基多苯基多异氰酸酯)为混合异氰酸酯,合成了聚氨酯(PU)胶粘剂预聚体;然后以PA(羟基丙烯酸酯树脂)作为PU预聚体的改性剂,制得高固含量的PUA(聚丙烯酸酯改性聚氨酯)胶粘剂。结果表明:当m(改性MDI)∶m(PAPI)=1∶1、n(-NCO)∶n(-OH)=2.2∶1、w(PA)=8%(相对于PU质量而言)和w(丙烯酸羟乙酯)=3%(相对于PU质量而言)时,PUA胶粘剂的综合性能较好。  相似文献   

19.
在常压酸催化作用下对竹屑进行多元醇液化,对液化产物的羟值和粘度进行了测定,并通过红外光谱、凝胶渗透色谱及GC-MS等对液化产物进行分析表征。结果表明:液化产物的羟值为350mgKOH/g,粘度为750mPa·s,相对分子质量分布范围在18~20 372之间,为连续分布形式,满足制备中强度硬质聚氨酯泡沫的要求。  相似文献   

20.
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   

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