POLYMERISATION PROCESS AND CATALYSTS

1313183 Olefin polymerization catalyst IMPERIAL CHEMICAL INDUSTRIES Ltd 19 Aug 1971 [3 Sept 1970] 42221/70 Heading C3P A catalyst for the polymerization of olefins comprises an organometallic compound of zirconium and 1,1,3,3-tetraphenyl-siloxane-1,3- diol. The silanol is preferably added to a preformed mixture of the zirconium compound with the olefin, usually in an inert solvent. The polymerization can be carried out either by the usual low pressure techniques or at high pressure (e.g. 2000 kg. cm.-2). Examples describe the polymerization of ethylene using tetrabenzylzirconium, tribenzylzirconium chloride or tetra-allylzirconium as the organometallic compound. Examples 54-56 describe high pressure polymerization of ethylene in the presence of hexene-1 and cyclohexene. Comparative examples describe the use of Ph 3 SiOH, Ph 2 Si(OH) 2 , and as the second catalyst component.