| abstract |
PROBLEM TO BE SOLVED: To provide an additive for cement which provides a cement composition whose compressive strength is drastically improved with a small amount of addition. SOLUTION: The additive for cement of the present invention comprises a vinyl alcohol-based polymer containing 0.1 to 45 mol% of a structural unit represented by the following chemical formula 1. Embedded image However, R 1 , R 2 : H or CH 3 X: COOH, CH 2 SO 3 H or CONHC (C H 3 ) 2 CH 2 SO 3 H, CH 2 OH, CH 2 CH 2 OH or CH 2 OCH 2 CH (OH) CH 2 OH, CONH 2 , C ON (CH 3 ) 2 , CH 2 N + (C 2 H 5 ) 3 Cl − or CO NH (CH 2) 3 N + (CH 3) 3 Cl - |