表面改性超细硅酸钙的制备及其性能表征

Preparation and characterization of surface modified ultrafine calcium silicate

采用沉淀法,以硝酸钙[Ca(NO3)2·4H2O]和硅酸钠(Na2SiO3·9H2O)为原料,在合成超细硅酸钙的同时对其进行表面改性。比较了聚乙二醇、硬脂酸钠、十二烷基苯磺酸钠等不同分散剂对硅酸钙粒径的影响,并分析讨论了其分散作用机理。采用激光粒度仪对产物进行粒径分析,并用X射线衍射仪(XRD)、红外光谱仪(FT-IR)以及扫描电子显微镜(SEM)对产物的物相、微观形貌等进行了表征。实验结果表明,选择合适的分散剂并控制工艺条件,可制得团聚度小的硅酸钙超细粉体。当在反应中添加占硝酸钙质量1%的聚乙二醇时,所制得的硅酸钙粉体的平均粒径为0.12μm,且晶粒尺寸均匀,结晶良好。

Ultrafine calcium silicate （CaSiO3） was prepared by precipitation method,using Ca（ NO3 ）2 · 4H2O and Na2SiO3 · 9H2O as raw materials, and it was modified at the same time. Influence of different dispersion reagents, such as polyethylene glycol, sodium stearate, and sodium dodecylbenzene sulfonate on particle size of calcium silicate was investigated, and dispersion function mechanisms were discussed. Laser granularity meter, X -ray diffraction instrument （XRD）, infrared absorption spectrometer（ IR ）, and scanning electron microscopy（SEM ） were used to characterize size distribution, phase composition,and micromorphology of the products. Results showed that ultrafine calcium silicate powder with small agglomeration could be prepared by choosing appropriate dispersant and controlling technical conditions. When additive of polyethylene glycol was 1% （ mass fraction） of Ca （ NO3 ） 2 · 4H2 O, the average size of obtained calcium silicate powder was 0.12μm and particle size was homogeneous and crystallization was fine.