| 摘要 |
1,260,381. Polymerization of ethylene. IMPERIAL CHEMICAL INDUSTRIES Ltd. 12 Jan., 1970 [20 Jan., 1969; 30 Oct., 1969], Nos. 3136/69 and 52364/69. Heading C3P. Ethylene is polymerized at a pressure greater than 1000 Kg./cm.<SP>2</SP> and at temperatures above 125‹ C. in the presence of a catalyst which comprises a compound of a transition metal capable of polymerizing ethylene, and also in the presence of 0À5-20% by weight based on ethylene of an "allylic compound" of the formula wherein R 1 , R 2 , R 4 and R 5 are hydrogen or hydrocarbon radicals and R 3 is a hydrocarbon radical, preferably both R 3 and R 2 being hydrocarbon radicals. The double-bonded carbon atoms in the "allylic compound" may form part of a six-membered ring, e.g. cyclohexane, methylcyclohexane, 1,2,3,4 - tetrahydronaphthalene. Alternatively the allylic compounds may be terpenes preferably alpha-pinene. The catalyst may be titanium tin- or tetra-chloride or a vanadium chloride or oxyhalide used with aluminium triethyl or aluminium diethyl chloride, or may be a zirconium-#-allyl complex. Polymerization may be effected in the presence of hydrogen. |
