Process for producing α-olefin polymer

Claim 1

A process for producing an α-olefin polymer which comprises homopolymerizing an α-olefin selected from the group consisting of propylene, butene-1, and 4-methylpentene-1, or copolymerizing two or more of said α-olefins or one or more of said α-olefins and ethylene or an α-olefin containing 4 to 8 carbon atoms in the presence of a catalyst consisting essentially of: (I) a solid catalyst component prepared by contacting with each other, (A) a magnesium dihalide of the formula MgX 2 where x is a halogen atom, (B) an aromatic carboxylic acid ester, (C) titanium tetrachloride, and (D) a siloxyaluminum compound selected from the group consisting of trimethylsiloxyaluminum dichloride, triethylsiloxyaluminum dichloride, triphenyl-siloxyaluminum dichloride, trichlorosiloxyaluminum dichloride, a reaction product of dimethylpolysiloxane and aluminum chloride, a reaction product of methylphenylpolysiloxane and aluminum chloride, or a reaction product of methylhydrogenpolysiloxane and aluminum chloride; and (II) organometallic compound of a metal of Groups I, II or III in the Periodic Table, wherein ingredient B is used in an amount of about 0.01 to 10 mols, ingredient C in an amount of about 0.001 to 1,000 mols, and ingredient D in an amount of about 0.001 to 1 mol, per mol of ingredient A; and wherein said ingredients A, B and D are pulverized together, contacted with ingredient C in a slurry state, and washed.