介孔分子筛负载茂金属催化乙烯聚合的研究进展

Progresses in Ethylene Polymerization Catalyzed by Mesoporous Molecular Sieve Supported Metallocenes

介绍了几种常见介孔分子筛(FAU、MFI、M41S系列和SBA系列),综述了介孔分子筛负载茂金属催化乙烯聚合的研究进展,重点分析了介孔分子筛化学组成及孔道结构对负载茂金属催化剂活性及聚合产物的影响,对比分析了介孔分子筛与其他几种常见无机载体(硅胶、氯化镁和黏土)的优缺点。介孔分子筛不仅承载了茂金属活性中心,改善了其分散性,而且其特殊的纳米孔道结构对乙烯单体的扩散有一定的限制作用,导致聚合产物相对分子质量及其分布、形态发生变化。

Several mesoporous molecular sieves （FAU, MFI, M41S and SBA） in common use were introduced, and the progresses in the ethylene polymerization with the mesoporous molecular sieve supported metallocene catalysts were reviewed. The effects of the chemical composition and pore structures of the mesoporous molecular sieves on the catalyst activities and product properties were discussed. The differences between the mesoporous molecular sieves and other commonly used catalyst supports （i.e. SiO2, MgC12 and clay） were analyzed. In the polymerization process, the mesoporous molecular sieves load the metallocene active sites and change their dispersity, and their specific nano- pores restrict the monomer ethylene diffusion, which results in that the relative molecular mass of the product polyethylene, the relative molecular mass distribution and the product morphology change with the pore structure.