| 摘要 |
A copolymer of (a) from 96 to 99.6% molar of ethylene and (b) from 0.4 to 4% molar of a C3-C6-alkenoic acid or an ester thereof having not more than 14 carbon atoms or a mixture of these monomers, which copolymer may be prepared by polymerization in a continuously operated tubular reactor under a pressure of from 500 to 5,000 bar and at elevated temperature in the presence of free-radical initiators by feeding a mixture of the said reactants to the inlet port of the reactor only, restricting the temperature in a first reaction zone to approximately 240° C. and, after the temperature has dropped by from 5°to 20° C., metering further initiator to the beginning of a second reaction zone and completing the reaction at a temperature of up to 300° C.
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