| 摘要 |
PURPOSE:To form an admixture for cement capable of preventing lowering of fluidity and air amount of concrete with the lapse of time and having excellent freezing and melting properties by blending fine grains of a copolymer (salt) of olefin and ethylenic unsaturated dicarboxylic acid anhydride and a water reducing agent and defoaming agent for concrete as essential components. CONSTITUTION:The aimed admixture for cement obtained by blending (A) fine grains of a copolymer of 2-8C olefin and ethylenic unsaturated dicarboxylic acid anhydride or fine grains of a polyvalent metal salt thereof with (B) a water reducing agent and (C) defoaming agent for concrete as essential components. As necessary,(D) the foaming agent may be added to the above- mentioned composition. The component B is preferably usedat a wt. ratio of the component B to the component A of 1:99-99:1. The component C is mainly composed of dimethylpolysiloxane and preferably used at a wt. ratio of 0.001-5:100 based on total amount of the component A and component B. |
