| 摘要 |
PURPOSE:To provide the titled additive which yields mortar and concrete products having no air bubbles on the surface and having excellent appearance when added in a small amt. to cement by consisting the additive of specific alcohols and urethane compd. CONSTITUTION:The adduct of the ethylene oxide and/or propylene oxide of monohydric alcohol of 1-18C and an isocyanate compd. (example: ethylisocya nate) are brought into urethane reaction, by which the urethane compd. (B) expressed by formula II (R' is alkyl, alkenyl, alkylaryl of 1-18C; (n), (p) are 0-60; (q) is 1, 2; n+p=15-60; part of a residual urethane group may be converted to urethane by alcohols if (q) is <=2; X is a residual urethane converted group of the isocyanate compd.) is obtd. (A) 10-99.5wt.% alcohols expressed by formula I (R is R'; l is 0-20; (m) is 0-60; l+m=0-60) and 90-0.5wt.% component B are then compounded to obtain the cement additive. 0.01-1pt.wt. said additive is added to 100pts. cement.
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