Study on Ethylene-alpha-Olefin Copolymerization Catalyzed by the MgCl_2-Supported and Low Ti-Loading Ziegler-Natta Catalyst

摘要

Ethylene-alpha-olefins copolymers were synthesized with MgCl_2-supported and low Ti-loading Ziegler-Natta catalyst prepared using the one-pot balling method.The effects of the type of comonomer,the concentration of comonomer,and polymerization temperature on the catalytic activity,kinetic behavior,molecular weight,and its distribution of the resultant copolymer were studied.It was found that the resultant copolymers have a wide molecular weight distribution.The formation mechanism of polymer with broadened molecular-weight distribution was also discussed using the method of fitting the molecular weight distribution (MWD) curves with multiple Flory-Schulz functions.