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基于四氢呋喃聚醚聚氨酯弹性体力学性能的研究 总被引:5,自引:2,他引:5
以四氢呋喃聚醚(PTMG)、二异氰酸酯(TDI、或MDI)和扩链剂(MOCA、或BDO)为原料,制备了浇注型和热塑型聚氨酯弹性体。研究了预聚体的NCO基质量份、PTMG的分子量和硬段质量份数对PU弹性体力学性能的影响。结果表明:PU弹性体的硬度和模量随NCO含量和硬段质量份数增加而增加。逐渐提高PTMG的分子量,PU弹性 的拉伸强度降低,而拉断伸长率增加。2000分子量的PTMG-PU弹性体的冲击弹性比1000分子量的PTMG-PU好。 相似文献
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聚醚聚氨酯弹性体及其老化性能研究 总被引:2,自引:0,他引:2
邹德荣 《合成材料老化与应用》2002,31(2):13-18
以三羟基四氢呋喃环氧丙烷共聚醚(JF)、甲苯二异氰酸酯(TDI)、一缩二乙二醇(DEG)、白碳黑为原料,采用一步法合成了聚醚聚氨酯弹性体。研究了扩链比例,异氰酸酯指数、白碳黑含量对弹性体性能的影响,进行了正硫化点和加速老化试验,测试了弹性体的力学性能和为粘度变化。结果表明,一缩二乙二醇(BC)和三羟基四氢呋喃环氧丙烷共聚醚(JF)的羟基比例控制在2.5,异氰酸酯指数为1.20,白碳黑含量为10g,固化温度为70℃,固化时间为10h,可以获得工艺性能良好,力学性能良好的聚醚聚氨酯弹性体。 相似文献
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苯乙烯系热塑性弹性体的热氧老化 总被引:4,自引:0,他引:4
利用自制的热氧老化装置对苯乙烯系热塑性弹性体及其环氧化物进行了热氧老化研究,考察了不同结构、环氧度及防老剂对苯乙烯系热塑性弹性体耐老化性能的影响。结果表明,对双键进行环氧化增加了苯乙烯系热塑性弹性体的极性,改善了其黏接性能和耐老化性能。加入新型防老剂504的环氧化热塑性弹性体具有较好的抗老化效果。 相似文献
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PTMG与过量的2,4-TDI合成端异氰酸预聚体后,用MOCA扩链制成浇注型PUR。确定了预聚反应的最佳工艺条件;并研究了NCO%对PUR的扯断强度和硬度的影响。 相似文献
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原料对聚氨酯弹性体透明性的影响 总被引:9,自引:0,他引:9
研究了采用不同类型的异氰酸酯、聚合多元醇及扩链剂合成透明聚氨酯(PU)弹性体,详细讨论分析了异氰酸酯的种类、多元醇的种类及分子量、扩链剂的类型及结构特点、微量水分等对PU透明性的影响。结果表明,采用脂环族异氰酸酯IPDI或脂肪族异氰酸酯HDI,分子量为1000-2000的聚醚二元醇PTMEG和丁二醇BOD类扩链剂制备出的PU具有优异的透明性;同时结合PU的力学性能,进一步明确透明PU的原料及配方,结果显示:n(IPDI):n(PTMEG1000):n(1,4-BOD)=2:1:1时的PU具有最好的综合性能。 相似文献
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聚氨酯弹性体耐热性的影响因素 总被引:14,自引:1,他引:14
讨论了多异氰酸酯,聚合物多元醇,扩链剂,分子内基团,杂环,离子基团对聚氨酯弹性体耐热性能的影响。指出开发新原料,引入热稳定杂环,严格控制反应条件和原料的纯度及配比,是提高聚氨酯弹性体耐热性的有效途径。 相似文献
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聚ε-己内酯型热塑性聚氨酯弹性体的合成 总被引:1,自引:0,他引:1
简单介绍了聚ε-己内酯型热塑性聚氨酯弹性体的合成工艺.研究了聚ε-己内酯分子量、硬段含量、n(-NC0)/n(-OH)和异氰酸酯结构对其性能的影响。结果表明.n(-NC0)/n(-0H)和异氰酸酯结构对热塑性聚氨酯弹性体的熔融指数、微相形态结构和物理机械性能有较大的影响。 相似文献
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通过傅里叶红外变换光谱、热分析与力学性能测试,研究了抗氧剂四(3,5-二叔丁基-4-羟基苯丙酸)季戊四醇酯(Irganox1010)对聚氨酯弹性体老化性能的影响。力学测试结果表明,150℃下老化48h后,未加抗氧剂的聚氨酯弹性体的拉伸强度与老化前相比较下降11.6%,而添加抗氧剂的聚氨酯弹性体的拉伸强度与老化前相比较没有下降。热重分析、差示扫描量热分析和红外光谱分析结果表明,抗氧剂Irganox1010能阻碍聚氨酯分子链的断裂,减缓材料的老化,因此能促进聚氨酯弹性体的抗老化性能。 相似文献
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A polyurethane elastomer having mechanical and adhesive properties suitable for liner applications in solid rocket propellants was developed using HTPB as the prepolymer and IPDI as the curing agent. The effects of the NCO/OH ratio (R value) and the trio/diol ratio on the mechanical properties of the polyurethane matrix were investigated. The reaction of HTPB and IPDI is followed by monitoring the changes in the IR absorption bands of the NCO stretching at 2255 cm−1 and the CO stretching at 1730 cm−1. It was found that the rate of the polyurethane formation obeys an overall second-order kinetics. At an R value of 1.15, the elastomer shows the maximum tensile strength and 200% elongation at break. The hardness, elongation, and the tensile strength reach a steady value around the same R value. The elastomers having a triol/diol ratio less than 0.03 show a decrease in the tensile strength and modulus with a concomitant increase in elongation. At a triol/diol ratio greater than 0.05, the tensile strength increases to about the same value for the liner composition without any triol component. The elongation reaches a steady level at a triol/diol ratio of 0.10 and one observes a steady increase in hardness up to 0.5. The modulus for the compositions having a triol/diol ratio greater than 0.1 is about 50% higher than that for the composition without triol. © 1997 John Wiley & Sons, Inc. J Appl Polym Sci 64: 2347–2354, 1997 相似文献
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Effect of side methyl groups of polymer glycol on elongation-induced crystallization behavior of polyurethane elastomers 总被引:1,自引:0,他引:1
Effect of side methyl and dimethyl groups of soft segment component on polyurethane elastomers (PUEs) was investigated with and without elongation. The polymer glycols used were poly(oxytetramethylene) glycol (PTMG), PTMG with dimethyl groups (PTG-X) and methyl groups (PTG-L). Phase separation of the PUEs became weaker with an increasing methyl group content. Tensile test revealed that the increasing methyl group concentration made the PUEs be soften and weaken. The PTMG based PUEs obviously exhibited elongation-induced crystallization during elongation process. In contrast, for the PTG-L and PTG-X based PUEs, crystallinity decreased with an increasing side methyl group content, and the PUEs with PTG-L and PTG-X with highest methyl group content did not crystallize. We succeeded the control of the crystallization behavior of elastomers under an elongation by the introduction of side methyl groups. 相似文献