Methyl-pentene copolymer with hexene and higher olefin! - produced by two=stage polymerisation using transition metal and organo metallic catalysts

摘要

4-Methyl-1-pentene copolymer is produced by a 2-stage polymerisation. In the first stage 4-methyl-1-pentene is polymerised in a liq. hydrocarbon in the presence of a catalyst comprising a transition metal cpd. or an organo-metallic cpd. of a Gp. I-VI metal. The polymer (A) produced contains >=90wt.% 4-methyl-1-pentene with 0-10wt.% of a 6-18C linear 1-olefin. 4-Methyl-1-pentene, 1-hexene and a 7-10C linear 1-olefin are then copolymerised in the presence of the polymer (A) to form a rubbery copolymer (B) contg. 30-70 wt.% 4-methyl-1-pentene, 10-60 wt.% 1-hexane and 10-60 wt. % 7-10C linear 1-olefin. The copolymer (B) forms 5-20 wt.% of the polymer compsn. The polymer compsn. has improved impact strength while retaining the lightweight and transparency of 4-methyl-1-pentene polymers. It resists whitening and delamination on bending or impact.