GB1314198A - Process for polymerizing alpha-olefins - Google Patents

Abstract

1314198 Olefin polymerization catalyst FARBWERKE HOECHST AG 21 Dec 1970 [22 Dec 1969] 60672/70 Heading C3P Olefins of formula R-CH=CH 2 , where R is a C 1 -C 10 hydrocarbon radical, are polymerized at 20-200‹ C. and at pressures up to 50 atm. by means of a catalyst comprising (A) the hydrocarbon-insoluble product of reacting (a) an hydroxyl-containing magnesium compound, (b) a chlorine-containing Ti(IV) compound, and (c) an aluminium alkoxide and/or silicic acid alkyl ester; and (B) an organoaluminium compound. Component (A) is preferably prepared by reacting (a) with the pre-formed reaction product of (b) with (c), but all three can be reacted simultaneously or (b) can be reacted with the reaction product of (a) and (c). Suitable magnesium compounds include Mg(OH) 2 and basic magnesium chloride, nitrate, carbonate, sulphate, phosphate and acetate. The polymerization may be carried out in an inert diluent or in the gas phase, e.g. using preformed polymer to disperse the catalyst. Examples describe homopolymerizations of ethylene and propylene and copolymerization of ethylene with propylene or butene-1, catalyst component (A) being formed from TiCl 4 , one of the above-mentioned catalyst supports and Al(O-i-Pr) 3 , Al(O-i-Bu) 3 , Si(O-i-Pr) 4 or Si(O-i-Pr) 4 /Si(OEt) 4 and component (B) being AlEt 3 or Al(i-Bu) 3 . The activity of the catalysts is such that purification of the resulting polymers is not usually necessary.