| 摘要 |
<p>A continuous process for the polymerization of ethylene at 90 DEG to 350 DEG C. and a pressure of at least 15000 p.s.i.g. comprises introducing a mixture of ethylene, free radical catalyst and a chain-transfer agent and/or a copolymerizable monomer into an elongated tubular reactor zone having a length to diameter ratio of at least 250:1, the mixture being in two or more streams each containing ethylene, one stream being introduced at an inlet point of the reactor zone and another stream of streams at side points from 15 to 85% of the distance between the point of introduction of the first stream and the point of discharge of the polymer from the zone. Reaction mixture components specified include oxygen, peroxide and azo catalysts; carbon monoxide; sulphur dioxide; telogens such as carbon tetrachloride, chloroform, saturated ethers, esters, acids, anhydrides and acetals; chain transfer agents such as aliphatic alcohols, ketones and aldehydes, olefins, hydrocarbons, acetylenic compounds and chlorinated aldehydes or hydrocarbons; and numerous unsaturated monomers, in particular acrylic monomers such as ethyl acrylate and vinyl carboxylates such as vinyl acetate.</p> |
