MALEIC ACID COPOLYMER, PROCESS FOR PRODUCING THE SAME AND USE THEREOF

摘要

A maleic copolymer having a weight-average molecular weight of 1,000 to 100,000, a calcium ion scavenging capacity of at least 300 mgCaCO3/g, and a clay dispersing capacity of at least 1.2; and another maleic copolymer having a clay adsorption rate of 20-90 % and a stability constant with respect to calcium ions of at least 4.0. The process for producing these copolymers comprises the step of feeding maleic acid and/or its salt (A) in a concentration of at least 35 wt. % into a reactor, the step of feeding thereafter hydrogen peroxide in an amount of 3-20 wt. % based on the component (A) into the reactor, and the step of feeding thereafter a water-soluble ethylenic monomer (B) in a molar ratio of the component (A) to the component (B) of 95/5 to 5/95 into the reactor within a period of 30 to 500 minutes after the starting of the reaction, said monomer feed step being completed 10 to 300 minutes after the completion of said peroxide feed step. The obtained copolymers are used as a detergent composition, inorganic pigment dispersant, water treatment and fiber treatment.