摘要 |
1467042 Ethylene polymerization in bulk SNAMPROGETTI SpA 24 May 1974 [15 June 1973] 23477/74 Heading C3P Ethylene is polymerized in the presence of a catalyst comprising a transition metal compound and an aluminium compound AlR x X 3-x where R is hydrocarbyl or hydrogen, X is halogen and x is above 0 and up to 3 in a reaction medium, the majority of which comprises liquid ethylene, at a temperature from - 50‹ C. to the initial temperature of ethylene, and with a concentration of transition metal compound not exceeding 0À01 m. moles per litre of liquid ethylene. The product may be obtained in the form of fibrids, powders or flocks. Examples refer to the production of polyethylene in liquid ethylene at temperatures of -10‹ to - 45‹ C., using a VOCl 3 and Al 2 Et 3 Cl 3 catalyst. |