不同相对分子质量木素磺酸钙减水剂的性能

应用超滤分级方法，将木素磺酸钙分成不同相对分子质量范围的级分，发现高相对分子质量的级分比低相对分子质量的级分具有更高的表面活性和起泡性能；低相对分子质量（小于30000）级分在水泥颗粒表面和饱和吸附量随相对分子质量的增大而增加，而高相对分子级分的饱和吸附量基本不受相对分子质量的影响；当木素磺酸钙的掺杂量高于0．5％（质量分数）时，其对水泥的分散作用随相对分子质量的增大而增强。随着木素磺酸钙相对分子质量的增大，掺木素磺酸钙的水泥净浆流动度损失逐渐减少，混凝土的含气量增大，抗压强度降低。

Properties of Calcium Lignosulfonate Water Reducers with Different Relative Molecular Mass

In this paper, the calcium lignosulfonate (CL) was fractionated by means of ultrafiltration. It is found that the surface activity and foaming propertiy of CL fraction with high relative molecular mass are higher than those with low relative molecular mass. The saturation adsorption amount of CL fraction with low relative molecular mass (less than 30 000) on cement particles increases with the increasing of relative molecular mass, while the saturation adsorption amount of CL with high relative molecular mass is independent on relative molecular mass. When the dosage of CL is more than 0.5%(mass fraction), the dispersive effect of CL fractions on cement paste increases with relative molecular mass. With the increasing of relative molecular mass, the loss of flowability of cement paste decreases, the air content of concrete increases and the compressive strength of concrete decreases.