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这种外加剂不但能减少混凝土或砂浆自流及泵送时的摩擦阻力,而且有良好的减水作用,因而还能大幅度地提高混凝土的强度。该外加剂是由平均分子量超过40000的聚乙烯吡咯烷酮(Polyvinylpyrrolidone)及分子量为1500或大于15O0的萘磺酸钠甲醛缩合物组成的。其中聚乙烯吡咯烷酮占0.5～10％的重量,其余是萘磺酸钠甲醛缩合物。换言之,后者占90～99.5％。这两种材料先经混合并掺入还没有加水的干燥水泥之中
This admixture can not only reduce the frictional resistance of concrete or mortar when it is free flowing and pumping, but also has a good water reducing effect, which can also greatly increase the strength of the concrete. The additive is composed of polyvinylpyrrolidone having an average molecular weight of more than 40,000 and sodium naphthalenesulfonate formaldehyde condensate having a molecular weight of 1500 or more. Among them, polyvinylpyrrolidone accounts for 0.5 to 10% by weight, and the rest is sodium naphthalenesulfonate formaldehyde condensate. In other words, the latter accounts for 90-99.5%. The two materials are first mixed and mixed into dry cement that has not yet been filled with water.