| 摘要 |
1,233,064. Polymerizing acrylic esters. BADISCHE ANILIN- & SODAFABRIK A.G. 8 Aug., 1968 [9 Aug., 1967], No. 37806/68. Heading C3P. A process for polymerizing an acrylic ester in the presence of a polymerization initiator with or without one or more comonomers comprises introducing the acrylic ester (e.g. an ester of acrylic, methacrylic, α-chloroacrylic or α-cyanoacrylic acid) and any comonomer used into a reaction zone and subjecting the monomer(s) to a polymerization reaction in which less than 1 % by weight of total monomer is polymerized, then removing the unpolymerized monomer(s) from the zone and separating off polymer formed, and polymerizing the monomer(s) thus obtained in a second reaction zone. (Impurities present in the starting monomer(s) are removed in the initial polymerization step.) In examples, the monomers used are the methyl, ethyl, n-butyl and 2-ethylhexyl esters of acrylic acid, which after initial treatment with a polymerization catalyst are homopolymerized either in isobutanol with azoisobutyronitrile catalyst or in aqueous emulsion with potassium persulphate catalyst. |
