GB1414312A - Production of alphaolefin polymers - Google Patents

Abstract

1414312 Olefin polymerization catalyst MITSUBISHI PETROCHEMICAL CO Ltd 24 Nov 1972 [27 Nov 1971] 54375/72 Heading C3P An α-olefin polymerization catalyst comprises (1) a solid composition or slurry thereof obtained by milling α-TiCl 3 in the presence of a halogenated hydrocarbon and (2) an organo aluminium compound which may have the formula AlR n X 3-n where R is a hydrocarbon radical, X is halogen or hydrogen and n is 1, 1À5, 2 or 3. The catalyst may also contain a cycloheptatriene compound, e.g. cycloheptatriene, a tropylium salt, a tropylium complex, a halogen, alkyl, aryl, alkaryl, aralkyl, cycloalkyl or halohydrocarbon substituted cycloheptatriene, a tropolone or a tropone. An extensive list of suitable cycloheptatriene compounds is included in the Specification. The catalyst is used for polymerizing α-olefins (e.g. ethylene, propylene or butene-1) in the substantial absence of solvent. In the examples propylene is polymerized in the presence of polypropylene and in the presence and absence of hydrogen using triethylaluminium or diethylaluminium chloride and the product obtained by reducing TiCl 4 with Ti to give α- TiCl 3 which is ball milled with one of 1,5-dichloropentane, CCl 4 , CHCl 3 , CH 2 Cl 2 , CH 2 Cl 4 , C 2 Cl 6 , C 2 Cl 4 , CH 2 Br 4 , CH 2 Br 2 , 1,2-dichloropropane, 1,3-dichloro- or dibromopropane, propenylchloride, dichloride or bromide, 1,4-dichlorobutane, perchlorobutadiene, tetrabromobutane, perchlorocyclopentadiene, 1,6-dichlorohexane, hexachlorobenzene or benzyl chloride. In one example methoxyethyltropyl ether was present in the polymerization medium. Reference examples also relate to solvent polymerization of propylene using triethylaluminium and α-TiCl 3 milled with 1,3- diehloropropane and to using α-TiCl 3 milled alone but with CCl 4 or hexachlorobenzene added to the polymerization medium.