【摘要】 针对丁羟聚氨酯弹性体的老化及其对材料性能的影响,制备了丁羟弹性体胶片试样,对试样进行了加速老化试验,测试了不同老化阶段弹性体的密度、力学性能、交联密度及红外光谱.通过对测试结果的分析,指出了丁羟弹性体体系内部发生的化学反应及其对力学性能的影响,总结了丁羟弹性体的老化规律.研究发现在老化过程的前期,MAPO与TDI也发生了交联反应,使弹性体的交联密度有所增加,弹性体内的化学反应主要以降解断链为主,通过弹性体熵弹性的降低来影响其力学性能,该阶段弹性体的力学性能并不随交联密度而变化.在老化过程的后期,弹性体内部以氧化交联反应为主.更多还原

【Abstract】 Mechanical properties and chemical structure parameters of HTPB polyurethane elastomer during its accelerated aging process were measured and analyzed.The corresponding chemical reactions in HTPB based elastomer system and the effects on the mechanical properties of the system were indicated,and the aging law of the HTPB based elastomer were summarized.Besides,the results show that at the earlier stage of the aging time,the crosslink reaction of MAPO and TDI in the elastomer makes the crosslink density become higher,the main chemical reaction of the elastomer is degradation and chain scission of the polymer.The mechanical properties of the elastomer are related to the entropy elasticity and not related to the crosslink density in this stage.At the later stage of the aging time,the main chemical reaction of elastomer is crosslink.更多还原