High degree of polymerization process for producing polyvinyl ester polymer and a high degree of polymerization of polyvinyl alcohol - the manufacturing method of Le polymer

摘要

PURPOSE:To readily produce the titled polymer at a high rate and on an industrial scale, by emulsion polymerizing a vinyl ester monomer under specific condition and, as necessary, saponifying the resultant polymer. CONSTITUTION:A vinyl ester monomer, e.g. vinyl acetate, etc., is emulsion polymerized in water or a blend of water wit one or more of a water-soluble alcohol, glycol, glycerol or inorganic salt as a medium using one or more of a nonionic emulsifying agent, e.g. polyoxyethylene alkyl ether, etc., nonionic- anionic emulsifying agent, e.g. phosphoric acid ester of a polyoxyethylene alkyl ether, etc., or anionic emulsifying agent, e.g. phosphoric acid ester of a higher alcohol, etc., as an emulsifying agent and combination of (A) one or more of a hydroperoxide, peroxide and peracid ester and (B) metallic ions, e.g. Fe2+, etc., capable of receiving one electron transfer or the components (A) and (B) and a reducing substance as an initiator at -60-+15 deg.C and the resultant polymer is saponified, as necessary, to afford the aimed polymer having =1.5dl/g intrinsic viscosity.