GB1314005A - Polymerisation catalyst - Google Patents

Abstract

1314005 Polymerizing olefins INTERNATIONAL SYNTHETIC RUBBER CO Ltd 1 July 1970 [1 April 1969 24 Feb 1970] 17025/69 and 8816/70 Heading C3P Olefins may be polymerized in the gaseous or liquid phase in the presence of a supported catalyst prepared by intimately contacting (B) a Grignard reagent with a particulate solid support comprising a metal salt and/or oxide having a solubility in water of less than 1À0 gm./litre at 20‹ C., and thereafter adding a compound of a transition metal of Groups IVa to VIII having at least one ligand exchangeable with the hydrocarbyl of the Grignard reagent. Preferred supports are compounds of Group IIa metals, zinc and aluminium, particularly oxides, halides, carbonates, silicates, borates, phosphates and sulphates, of particle size below 1 mm. Solid components of the catalyst may be ground or pelletized before or after reaction to modify the particle size, or subjected to ultrasonic vibrations in the presence of an organic dispersant. The catalysts may be used to polymerize ethylene, optionally together with propylene and dienes such as dicyclopentadiene, 1,4 - hexadiene or 5 - ethylidene - 2 - norbornene; and the resulting polymers may be cured by conventional peroxide or sulphur cures. Many examples are given describing the polymerization of ethylene optionally together with (5 and 12 to 18) propylene and (19) propylene and 5-ethylidene-2-norbornene in the presence of catalysts formed from (A) titanium tetrachloride, vanadium oxytrichloride or zirconium tetrachloride, (B) phenyl magnesium bromide or methyl magnesium bromide, using as support cryolite, γ-alumina, calcium carbonate, magnesium oxide or zinc oxide. The catalysts may be activated by further (B) compounds, e.g. aluminium tributyl, aluminium triisobutyl, aluminium triethyl or zinc diethyl; and the polymerization may be effected in the presence of hydrogen.