Patent ID: 7521517
Filing Date: 2009-04-21
Classification: C08F

Abstract:
1. A method for producing a carboxyl group-containing water-soluble polymer comprising reacting an α, β-unsaturated carboxylic acid and a compound having two or more ethylenically unsaturated groups in the presence of a radical polymerization initiator, wherein the reaction is carried out in an inert solvent which is incapable of dissolving the carboxyl group-containing water-soluble polymer produced and in the presence of a (meth)acrylic acid derivative represented by the general formula (1): wherein R 1 and R 2 each independently represents a hydrogen atom or a methyl group and n represents 1 or 2, wherein the compound having two or more ethylenically unsaturated groups is used in an amount of 0.15 to 2 parts by weight per 100 parts by weight of the α, β-unsaturated carboxylic acid, and wherein the compound having two or more ethylenically unsaturated groups is an allyl ether of a polyol selected from the group consisting of ethylene glycol, propylene glycol, diethylene glycol, dipropylene glycol, polyethylene glycol, polypropylene glycol, glycerol, polyglycerol, trimethylolpropane, pentaerythritol, saccharose and sorbitol.