【摘要】 以二乙二醇单乙醚基钡(简称Ba)/三异丁基铝(简称Al)/正丁基锂(简称Li)为三元引发体系,采用负离子聚合法合成了高反式苯乙烯-异戊二烯(Ip)-丁二烯(Bd)三元共聚物(SIBR),考察了引发剂组分、单体配比和聚合温度对SIBR微观结构的影响,并研究了Al/Li(摩尔比)和Bd/Ip(质量比)对SIBR结晶行为的影响。结果表明,所制得SIBR的数均分子量为1.60×105,分子量分布指数约为1.5;当Ba/Al/Li为1/4/4时,SIBR中反式结构摩尔分数达到最高,为85.6%;聚合温度和Bd/Ip对反式结构含量的影响不明显;随着Al/Li的增大,SIBR的玻璃化转变温度(Tg)略有降低;当单体配比中Bd含量较高时,SIBR出现冷结晶和熔融现象,随着Bd含量的减少,该现象消失且Tg升高。更多还原

【Abstract】 High trans styrene-isoprene-butadiene rubber(SIBR) was synthesized by anionic polymerization with barium salt of di(ethylene glycol) monoethyl ether(simplified as Ba)/triisobutyl aluminum(simplified as Al)/n-butyl lithium(simplified as Li) as initiation system,the effects of components of initiation system,ratio of monomers and polymerization temperature on microstructure of SIBR were investigated,and effects of Al/Li(mole ratio) and butadiene(Bd)/isoprene(Ip)(mass ratio) on glass transition temperature(Tg) and melting point were also studied.The results showed that the SIBR with number-average molecular weight of 1.60×105 and polydispersity index of 1.5 could be obtained.When Ba/Al/Li was 1/4/4,the mole fraction of trans-1,4-unit was up to 85.6%,but the polymerization temperature and ratio of monomers had little effect.The Tg of SIBR decreased gradually with the increase of Al/Li.When Bd was larger in the ratio of monomers,SIBR had cool crystallization and melting phenomena,but the phenomena disappeared and Tg increased with decreasing Bd.更多还原