结构调节剂双四氢糠丙烷对苯乙烯-异戊二烯橡胶微观结构的影响

采用活性阴离子聚合方法，以环己烷为溶剂，正丁基锂（n-BuLi）为引发剂，选取新型结构调节剂双四氢糠丙烷（DTHFP）（与传统的结构调节剂四氢呋喃和乙基四氢糠基醚进行比较）合成了苯乙烯（St）-异戊二烯（Ip）橡胶（简称戊苯橡胶，SSIR），考察DTHFP用量、St/Ip质量比、聚合反应时间和反应温度对SSIR微观结构的影响。结果表明，随着结构调节剂用量的增大，SSIR分子链中3，4-Ip结构含量均有所增大，3种结构调节剂中，DTHFP的调节能力最强，当DTHFP/n-BuLi物质的量比为0.5时，3，4-Ip结构质量分数高达0.680 5；DTHFP可以提高St和Ip单体的聚合速率，且对St单体聚合速率的调节能力更强；St/Ip质量比变化对Ip的微观结构影响不大；适当降低反应温度与增大DTHFP用量的效果相当。;A styrene（St）-isoprene（Ip） rubber（SSIR） was synthesized by a living anionic polymerization method using cyclohexane as a solvent and n-butyllithium as an initiator，and using new structure regulators 2，2-di（tetrahydrofuran-2-yl） propane（DTHFP）（comparing with the conventional structure regulators tetrahydrofuran and ethyl tetrahydrofurfuryl ether）.The effects of the addition level of DTHFP，the weight ratio of St/Ip，the reaction time and temperature on the microstructure of the SSIR were investigated.The results showed that the content of 3，4-Ip structural units in SSIR molecular chain increased with the increase of the addition level of structural regulator.Among the three structure regulators，DTHFP had the strongest regulation ability，when the molar ratio of DTHFP/n-BuLi at 0.5，the mass fraction of 3，4-Ip structural units was as high as 0.680 5.DTHFP could increase polymerization rate of St and Ip monomer，and the ability to adjust polymerization rate of St monomer was stronger.The change of weight ratio of St/Ip had little effect on the microstructure of Ip.The effect of lowering the reaction temperature appropriately was equivalent to increasing the addition level of DTHFP