| 摘要 |
An object is, in a fly ash-containing cement composition, to disperse fly ash well with addition of a small amount of additive to prevent the deviation of flowability of the cement composition due to the change of unburned carbon content. An additive for a fly ash-containing cement composition includes (A) a nitrogenous polyoxyalkylene derivative represented by formula (1) and (B) a polycarboxylic acid series copolymer having a polyoxyalkylene chain as essential components. R1 represents hydrogen atom or a hydrocarbon group having 1 to 22 carbon atom, R2 represents alkylene group having 1 to 4 carbon atom, A1O represents one or two or more oxyalkylene groups having 2 to 4 carbon atoms, which may be block or random in the case of two or more kinds of oxyalkylene groups, p=0 to 20, q=0 to 20, r=1 to 10, s=0 to 2 and t=0 to 2. |
