首页> 外文OA文献 >The effect of the amido substituent on polymer molecular weight in propene homopolymerisation by titanium cyclopentadienyl-amide catalysts
【2h】

The effect of the amido substituent on polymer molecular weight in propene homopolymerisation by titanium cyclopentadienyl-amide catalysts

机译:钛环戊二烯基-酰胺催化剂在丙烯均聚反应中酰胺基取代基对聚合物分子量的影响

代理获取
本网站仅为用户提供外文OA文献查询和代理获取服务,本网站没有原文。下单后我们将采用程序或人工为您竭诚获取高质量的原文,但由于OA文献来源多样且变更频繁,仍可能出现获取不到、文献不完整或与标题不符等情况,如果获取不到我们将提供退款服务。请知悉。

摘要

In the homopolymerisation of propene by the cyclopentadienyl-amide titanium catalyst systems [η5,η1-C5H4(CH2)2NR]TiCl2/MAO and [η5,η1-C5H4(CH2)2NR]Ti(CH2Ph)2/B(C6F5)3 (R = tBu, iPr, Me), the catalyst with the smallest substituent (Me) on the amido moiety consistently gives the highest polymer molecular weight. This differs from the trend usually observed in related catalysts with tetramethylcyclopentadienyl-amide ancillary ligands, where larger amide substituents result in higher molecular weights. Based on the present information a hypothesis is formulated in which an increased cation-anion interaction for the less sterically hindered catalyst is responsible for disfavouring chain transfer relative to chain growth.
机译:在丙烯通过环戊二烯基酰胺钛催化剂的均聚反应中,[η5,η1-C5H4(CH2)2NR] TiCl2 / MAO和[η5,η1-C5H4(CH2)2NR] Ti(CH2Ph)2 / B(C6F5)3 (R = tBu,iPr,Me),在酰胺基部分上具有最小取代基(Me)的催化剂始终提供最高的聚合物分子量。这不同于在具有四甲基环戊二烯基-酰胺辅助配体的相关催化剂中通常观察到的趋势,在该催化剂中,较大的酰胺取代基导致较高的分子量。基于当前信息,提出了一种假设,其中对于较少空间位阻的催化剂而言,增加的阳离子-阴离子相互作用导致不利于相对于链增长的链转移。

著录项

相似文献

  • 外文文献
  • 中文文献
  • 专利

客服邮箱:kefu@zhangqiaokeyan.com

京公网安备:11010802029741号 ICP备案号:京ICP备15016152号-6 六维联合信息科技 (北京) 有限公司©版权所有
  • 客服微信

  • 服务号