Process for production of 4-methyl-1-pentene polymer or copolymer

Claim 1

A process for producing a polymer or copolymer of 4-methyl-1-pentene, which comprises polymerizing 4-methyl-1-pentene or copolymerizing 4-methyl-1-pentene with up to about 20 mole % of an olefin having 2 to 20 carbon atoms at a temperature of from about 20° C. to about 100° C. and a pressure of from atmospheric to about 20 kg/cm 2 , in the presence of a catalyst comprising (A) a solid active titanium catalyst component composed of magnesium, titanium, halogen and a di(C 1 -C 20 )alkyl ester in which the two alkyl groups may be identical or different, of dicarboxylic acids in which one carboxyl group is attached to each of the adjoining carbon atoms (at the ortho-position) of an aromatic hydrocarbon moiety having 6 to 20 carbon atoms, and the magnesium/titanium atomic ratio of the catalyst component (A) is from about 2 to about 100, the halogen/titanium atomic ratio of the catalyst component (A) is from about 4 to about 100 and the diester/titanium mole ratio of the catalyst component (A) is from about 0.2 to about 10, said titanium catalyst being characterized by not substantially liberating a titanium compound when treated with hexane at room temperature, and (B) a tri(C 1 -C 15 )-alkyl aluminum compound and (C) an organosilicon compound represented by the following formula R.sup.1.sub.3Si(OR.sup.2) wherein each of R 1 and R 2 represents a hydrocarbon group with 1 to 5 carbon atoms, and the three R 1 groups may be identical or different, wherein prior to the polymerization or copolymerization, a methyl-pentene is pre-polymerized or pre-copolymerized in the presence of a catalyst comprising the catalyst component (A), a part of the catalyst component (B) and a part of the catalyst component (C) to form about 1 to about 1000 grams, per millimole of titanium atom, of a methylpentene polymer or copolymer, and the pre-polymerization or pre-copolymerization is carried out at a temperature of about -20° C. to about +70° C., and the polymerization or copolymerization is carried out at a temperature higher than that of the pre-polymerization or pre-copolymerization.