CEMENT ADDITIVE OR CEMENT COMPOSITION

摘要

PROBLEM TO BE SOLVED: To obtain a cement compsn. excellent in initial fluidity and the reduction of slump loss and preventing the decrease and excessive increase of the amt. of air during the kneading and transportation of the cement compsn. by incorporating a polyoxyalkylene compd. having a specified number of molds of added oxyalkylene groups as an essential component and a nonionic surfactant. SOLUTION: A polyoxyalkylene compd. (compd. A) having 30-500 mols of added 2-5C oxyalkylene groups as an essential component and a nonionic surfactant (compd. B) are incorporated. The compd. A preferably contains >=50 wt.% 2-5C oxyalkylene groups in its molecule. The compd. B is preferably used by 0.01-10 pts.wt. (expressed in terms of solid) based on 100 pts.wt. (expressed in terms of solid) of the compd. A. The compd. A is suitably used by 0.03-1 pts.wt. (expressed in terms of solid) based on 100 pts.wt. cement. The weight ratio of water to cement in a cement compsn. using the resultant additive is preferably <=50%.