| 摘要 |
PURPOSE:To obtain the title composition excellent in flexural and compressive strength and adherability to base materials and long in pot-life by incorporating cement with an admixture comprising a specific sulfonated melamine resin and an aqueous dispersion of a specific emulsion polymerization product. CONSTITUTION:An admixture comprising (A) a polymer aqueous dispersion (pref. acrylic, acrylic-styrene-based or SBR-based emulsion polymerization product) <=30 deg.C in polymer glass transition temperature, prepared by emulsion polymerization of an alpha,beta-ethylenic unsaturated monomer and (B) a sulfonated melamine resin, i.e., a melamine sulfonate HCHO condensate >=100000 in weight- average molecular weight, prepared, e.g., by reaction between an amino group- contg. substance consisting mainly of melamine, HCHO and an sulfite in an aqueous medium followed by pH adjustment, in the weight ratio (on a solid bases) A/B=(20/80) to (99/1) is incorporated into cement. |
