| 摘要 |
1,126,578. Polymerizing ethylene. LEUNAWERKE "WALTER ULBRICHT" VEB. 13 Dec., 1965, No. 52849/65. Heading C3P. Ethylene is polymerized at pressures above 500 atmospheres and temperatures of 50‹ to 400‹ C. in the presence of peroxide initiators having two or more peroxide and/or hydroperoxide groups having different decomposition temperatures, the reaction being effected so that each group takes effect on the reaction successively. The ethylene may be copolymerized with propylene, styrene, vinyl acetate, acrylic acid; ethyl acrylate, methyl methacrylate, acrylonitrile or maleic anhydride. The initiator may be mesityl oxide peroxide or the dihydroperoxide of dicyclohexanone peroxide. The reaction may be effected in tubular reactors or stirred autoclaves, and the initiator may be introduced in solution; e.g. in benzene, toluene, xylene, decane, cyclohexane or paraffin oil. Chain transfer agents, e.g. aliphatic, cycloaliphatic and halogenated hydrocarbons, alcohols, aldehydes, ketones and carboxylic acids, which may serve as solvents for the initiator, may also be present. Examples describe the polymerization of (1) ethylene and (2) ethylene and vinyl acetate in the presence of " mesityl oxide " peroxide, and of (3) ethylene in the presence of 1,1<SP>1</SP>-dihydroperoxy dicyclohexanone peroxide. |
