【摘要】 <正> 用烷基锂引发的丁二烯“活性”聚合,通常只能得到分子量分布较窄的聚合物。这类聚合物的门尼粘度较高,不易加工,且易冷流。为了解决这些问题,一般是合成分子量分布较宽且有一定支化的聚合物。但在以往的合成宽分布聚合物的方法中,大多只能得到非“活性”聚双烯烃,因而无法进行“活性”高分子的一些典型反应,如嵌段、接枝及偶更多还原

【Abstract】 The "living" polydienes with broad molecular weight distribution(MWD) have been synthesized by means of the continuous addition of initiator (sec-Buli). The investigations on the dependence of molecular weight upon conversion, the kinetic analysis on polymerization and the block polymerization of butadiene and isoprene have been made in order to confirm the fact that the detectable termination and transfer reactions are absent in the polymerization with the continuous addition of initiator. It has been found that the MWD of polymer can be controlled and varied over a wide range when the technique of continuous addition of initiator used and polymerization conditions, (such as the initiator amount, its addition rate, monomer concentration and polymerization temperature) changed.更多还原