PURPOSE: To prepare the title high polymer without forming crosslinking from acrylamide or a mixture of acrylamide and a water-soluble vinyl monomer in a mixture of water and a specified polar solvent by radiation polymerization.
CONSTITUTION: Polymerization reaction is carried out by dissolving a mixture of 100W20mol% of acrylamide and 0W30mol% of a copolymerizable water-soluble vinyl monomer which is selected from methacrylamide, (meth)acrylic acid (salt), diacetoneacrylamide, maleic acid (salt), vinyl-sulfonic acid (salt), into a mixture of water and one or more polar solvents of the formula IWIII (where R1-3 are methyl, ethyl) in a volume ratio of water to the solvent of 97:3W70:30 at a concentration of 5W80wt% and irradiating ionizing radiation at a temperature of -15W60°C in such a manner that exposure dose rate is from 102W104rad/hour and total exposure dose is from 103W105rad.
ISHIGAKI ISAO
ISHIWATARI AKIRA
KAMATA OSAMU
MITSUBISHI CHEM IND