SiO_2包覆超细CaCO_3的微晶分析和XPS研究

0引 言 超细碳酸钙在橡胶、塑料、造纸、涂料、油墨、医药、化妆品等工业中有广泛应用。碳酸钙粉末表面具有许多水羟基，表面是亲水疏油性的 ,易形成聚集体 ,分散性能差 ,直接应用效果不好。因此，根据其本身的性质及其应用目的，对其进行表面处理，以相应提高其应用性能。碳酸钙的表面处理是通过物理或化学方法将表面处理剂吸附或反应在碳酸钙的表面，形成表面改性层，使其表面活性化，以改善碳酸钙的表面性能。目前碳酸钙的表面改性大多为有机表面改性、偶连剂表面改性、高分子（聚合物）表面改性等 1]，而无机表面改性却很少有报道。我…

Minicrystal and XPS Analysis of SiO2 coated superfine CaCO3 Powder

The superfine CaCO3 powder coated with SiO2 was synthesized. Through XRD technique, the cell parameters and crystallite size of reference and coated CaCO3 were calculated. SiO2 present in the state of amorphous and prevent the agglomeration and growth of CaCO3 micro-crystal. By comparing the result of XPS analysis of reference compound to coated sample, CaCO3 has been coated successfully with SiO2. The thickness of the coating is about 2.4～3.4nm. From the difference (0. BeV increase) of the binding energy of Ca2p, we presume that the bind Si-O-Ca has formed in the surface of CaCO3.