Olefin block copolymer and production process thereof

摘要

A chemically bonded olefin block copolymer consists essentially of chemically bonded polypropylene and poly(ethylene-co-propylene). The block copolymer is obtained by a process of (1) introducing a Ziegler polymerization catalyst based on titanium and propylene to a first polymerization zone (a) and polymerizing the propylene in the polymerization zone (a) for a period of 0.01 to 0.130 seconds and withdrawing an effluent stream of polypropylene, catalyst, solvent and unreacted propylene therefrom; (2) introducing the effluent stream to a second polymerization zone (b) together with ethylene dissolved in a solvent and carrying out a polymerization reaction in the second polymerization zone (b) for a period of 0.01 to 0.130 seconds; and (3) recovering the block copolymer.