| 摘要 |
PURPOSE:To improve dispersibility of cement particles by mixing salt of sulfonated styrene-maleic acid copolymer, polyacrylic acid salt and salt of olefin-maleic acid copolymer. CONSTITUTION:100 pts.wt. salt of sulfonated styrene-maleic acid copolymer expressed by formula I (X<1>, X<2> and X<3> are Na, K, 1/2Ca, NH4 or organic amino group; l is 1-20; m is 1-3; n is 4-100) having from 500 to 5X10<4> number-average molecular weight is mixed with 10-300 pts.wt. polyacrylic acid salt having from 500 to 10<6> number-average molecular weight, 5-200 pts.wt. salt of olefin-maleic acid copolymer expressed by formula II (A is 2-8C linear olefin, 5-10C cyclic olefin aromatic-based olefin or derivative of said olefin; n is 4-200) having 1500-15000 number-average molecular weight and 0.01-30 pts.wt. anionic surfactant to afford additive for cement. Said additive in an amount of 0.01-1.00 pt.wt. calculated as solid is mixed to 100 pts.wt. cement mixture to obtain concrete composition. |
