用于合成间规聚丙烯的茂金属催化剂的研究进展

Progress in metallocene catalysts for the syndiotactic polypropylene

综述了间规聚丙烯(sPP)的发展历程、茂金属催化剂的种类和茂金属催化剂的负载过程,以及用于合成sPP的茂金属催化剂的结构特征和sPP的性能。重点讨论了单桥连茂金属催化剂、双桥连茂金属催化剂及限制几何构型茂金属催化剂的聚合性能及特点,并详细介绍了硅胶负载茂金属化合物/甲基铝氧烷催化体系的制备方法及其机理。通过设计催化剂结构、控制聚合条件可以实现对产物间规度、相对分子质量等参数的调控,负载化降低了茂金属催化剂工业应用的成本。

The development of syndiotactic polypropylene（s PP）,the types of metallocene catalysts and these loading process were overviewed. Both the structures and characteristics of metallocene catalysts for s PP were summarized. And the properties of correspondingly s PP products were also introduced. The performances and characteristics of single-bridged,doubly-bridged and constrained geometry metallocene catalysts were focused. In detail,the method and mechanism of silica-based loading process for metallocene/methylaluminoxane catalysts were introduced. The syndiotacticity and relative molecular mass of the product could be regulated by designing the catalyst molecular structures and monitoring polymerization conditions. The cost of industrial metallocene catalyst could be lower after being loaded.