Patent ID: 6153807
Filing Date: 2000-11-28
Classification: C07C,C08F,C10L,C10M,C10N,Y02P

Abstract:
A process for producing a copolymer of ethylene and an alpha-olefin having an ethylene content of from 40 to 60 mole %, a number average molecular weight of from 300 to 8200 and a molecular weight distribution defined by a Q value (the ratio of the weight average molecular weight to the number average molecular weight) of not more than 3 and a Z value (the ratio of the maximum value of the molecular weight to the minimum value of the molecular weight when the molecular weight is measured by gel permeation chromatography) of from 15 to 200, which comprises copolymerizing ethylene with an alpha-olefin in the liquid phase in the presence of a polymerization catalyst composed of a combination ofa soluble vanadium compound selected from vanadium compounds of the formulaVO(OR.sup.1).sub.n X.sup.1.sub.3-n and VX.sup.1.sub.4wherein R.sup.1 represents an aliphatic hydrocarbon group having 1 to 20 carbon atoms, X.sup.1 represents a halogen atom, and n is a number of from 0 to 3 andan organoaluminum compound in the co-presence of hydrogen, characterized in that(a) the copolymerization is carried out in a continuous manner,(b) the concentration of the vanadium compound in the polymerization system is maintained at 0.3 to 30 millimoles/liter, and(c) the vanadium compound is supplied to the polymerization system as a solution in a polymerization medium in a concentration which is 1-5 times the concentration of the vanadium compound in the liquid phase.