| 摘要 |
Ethylene is homopolymerized, or copolymerized with another a -olefin such as propylene, butene-1, butadiene or isoprene, by means of a catalyst formed from (1) A1, (2) a Ti or V di- or trihalide or mixtures thereof and (3) a Cu, Ag or Pb halide or mixtures thereof. The catalyst is used as a dispersion in a liquid vehicle normal pentane, hexane and decane, higher boiling petroleum fractions and cyclohexane (preferred) being specified. The polymer is isolated by use of an alcohol such as ethanol or propanol and preferably also by use of alcoholic hydrochloric acid under reflux. In Example 16, propylene polymerizes to a low molecular weight polymer and ethylene thereafter admitted to the reaction to form a solid copolymer.ALSO:A polymerisation catalyst is formed from (1) Al, (2) a Ti or V di- or tri-halide (e.g. TiCl2, TiCl3 or VCl3) or mixtures thereof and (3) a Cu, Ag or Pb halide (e.g. CuCl, CuCl2, CuBr, CuBr2, AgCl or PbCl2) or mixtures thereof. The Al may be in the form of an alloy (unspecified), but is preferably present as Al powder or flitter, particularly a powder of average particle size approximately 0.03m ; in some of the examples, the Al is milled in cyclohexane under nitrogen before use. The catalyst is used as a dispersion in a liquid vehicle, normal pentane hexane and decane, higher boiling petroleum fractions and cyclohexane (preferred) being specified. |
