Process and apparatus for producing ethylene polymer

摘要

An easily processible ethylene polymer having a molecular weight distribution different from that of a polymer conventionally produced in an autoclave reactor is obtained by a process for polymerizing ethylene or a mixture of ethylene with one or more other polymerizable monomers in a battery of autoclave reactors, which is characterized by connecting two or more autoclave reactors in series by means of piping provided with a heat exchanger; cooling the polymerization mixture withdrawn from the preceding reactor to a temperature above 120 DEG C. but lower than the reaction temperature in the preceding reactor by 20 DEG C. or more; and introducing the cooled polymerization mixture into the succeeding reactor to continue the polymerization. The molded articles, sheeting, and film prepared from the polymer thus obtained are markedly improved in optical properties.