DISPERSANT FOR REVERSE-PHASE SUSPENSION POLYMERIZATION AND PRODUCTION OF PARTICULATE POLYMER BY USING THIS DISPERSANT

摘要

PROBLEM TO BE SOLVED: To realize polymerization in a suspension state stable until the end of reaction, by subjecting a hydrophilic monomer to reversephase suspension polymerization in the presence of a radical polymerization catalyst in a solution obtained by dissolving a specified dispersant for reverse-phase suspension polymerization in an alicyclic or aliphatic hydrocarbon solvent. ;SOLUTION: A high-molecular compound of the formula (wherein R₁ is H or methyl; R₂ is an 8-18C alkyl; Y is H, ammonia, or an amine sa and (m) and (n) are each the number of repeating units comprising a group of monomers and giving a molecular weight of polymer of 1,000 to 500,000), in an amount of at least 7 wt.%, is blended with a sorbitan ester of a fatty acid, having an HLB of 3 to 10 to give a dispersant for reverse-phase suspension polymerization. This dispersant is dissolved in an alicyclic or aliphatic hydrocarbon solvent to give a solution. A hydrophilic monomer is subjected to reverse-phase suspension polymerization in the solution in the presence of a radical polymerization catalyst and, if necessary, a crosslinking agent having at least two double bonds in the molecule.;COPYRIGHT: (C)1999,JPO