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以n-BuLi为引发剂,环己烷为溶剂,四氢呋喃(THF)为结构调节剂,THF和叔丁基氧钾(t-BuOK)为无规化剂,在聚合温度为50℃时进行苯乙烯与丁二烯的二元共聚,考察了t-BuOK/n-BuLi(摩尔比)对共聚物结构的影响。结果表明,在THF/n-BuLi(摩尔比)控制为50的条件下,当t-BuOK/n-BuLi为0.5时,在整个聚合过程中,苯乙烯含量都保持在设计值附近,苯乙烯单元在大分子链上均匀无规分布,聚合物中1,2-结构摩尔分数为48.2%,达到中乙烯基含量。同时,THF对t-BuOK的调节作用具有一定的抑制效应,当t-BuOK/n-BuLi值小于0.5时,THF起主要调节作用;当t-BuOK/n-BuLi值大于0.5时,t-BuOK起到明显的调节作用。另外,双组分调节剂对共聚物的数均分子量和分子量分布影响不大。
Using n-BuLi as initiator, cyclohexane as solvent, tetrahydrofuran (THF) as structure regulator, THF and t-BuOK as randomizer, benzene The copolymerization of ethylene and butadiene was carried out to investigate the effect of t-BuOK / n-BuLi (molar ratio) on the structure of the copolymer. The results showed that the styrene content remained near the designed value for the entire polymerization when t-BuOK / n-BuLi was 0.5 at a THF / n-BuLi molar ratio of 50, The units were uniformly and randomly distributed on the macromolecular chains. The 1,2-structure mole fraction in the polymer was 48.2%, which reached the mid-vinyl content. At the same time, THF has a certain inhibitory effect on the regulation of t-BuOK. When t-BuOK / n-BuLi is less than 0.5, THF plays a major regulatory role. When t-BuOK / n-BuLi is greater than 0.5, t- BuOK played a significant regulatory role. In addition, the two-component regulators have little effect on the number average molecular weight and molecular weight distribution of the copolymer.