Patent ID: 6296698
Filing Date: 2001-10-02
Classification: C04B,C08F

Abstract:
A cement admixture comprising a copolymer obtained by polymerizing a monomer mixture comprising:(A) 2 to 85% by weight of a monomer represented by general formula (1) ##STR5##(wherein, R.sup.1 and R.sup.2, which are the same or different, each represent a hydrogen atom or a methyl group),(B) 90 to 10% by weight of one or more monomers represented by general formula (2) ##STR6##(wherein R.sup.3 represents a hydrogen atom or a methyl group, X represents --C(.dbd.O)-- or --CH.sub.2 --, Y represents an alkylene group having 2 to 4 carbon atoms, R.sup.4 represents a hydrogen atom or an alkyl group having 1 to 5 carbon atoms, and n is an integer of from 2 to 100), and(C) 5 to 50% by weight of a vinyl monomer containing a carboxylic acid group, or a salt of a carboxylic acid group; or a sulfonic acid group, or a salt of a sulfonic acid group,wherein the sum of the monomers (A), (B) and (C) is 100% by weight.