| 摘要 |
PROBLEM TO BE SOLVED: To improve slump retentivity by incorporating two kinds of specified polyethylene glycol (meth)acrylates and a carboxylic acid polymer (salt). SOLUTION: Five to 90wt.% polyethylene glycol (meth)acrylate represented by formula I (where R1 is H or methyl, R2 O is oxymethylene, R3 is H or 1-22C alkyl and (m) is 1-97 as the average mol number of added R2 O) and 5-90wt.% polyethylene glycol (meth)acrylate represented by formula II (where R4 is R1 , R5 O is R2 O, R6 is R3 , (n) is 4-10 as the average mol number of added R5 O, n≠m and n-m>=3) are blended with a copolymer of 5-90wt.% carboxylic acid monomer represneted by formula III (where R7 is R1 and M1 is H, a monovalent metallic atom, a divalent metallic atom, ammonium or an org. amine) with 0-50wt.% monomer copolymerizable with the carboxylic acid monomer or a copolymer salt obtd. by neutralizing the copolymer with an alkaline material so that the total amt. is regulated to 100wt.%. |
