超细碳酸钙的表面改性研究

Study of Surface Modification of Ultra-fine Calcium Carbonate

采用双复合法新工艺(工艺复合和物相复合,前者是"机械化学力与水热法复合",后者是"纳米物相与超细粉体复合")改善超细碳酸钙的颗粒大小、分散性以及分散稳定性。利用自分散型和晶型结构好的纳米AlOOH对超细碳酸钙进行改性,并用透过率、粒度分析、Zeta电位、红外和SEM表征超细碳酸钙的改性效果。结果表明:超细碳酸钙的粒径明显变小,颗粒分布均匀,在水相中分散稳定性变高,能很好地分散在水性涂料中。水热反应温度为120℃,反应时间为180min,填充度为50%,超细碳酸钙的溶度为0.4mol/L,物质的量比3∶1时改性的超细碳酸钙的效果最佳。

New technology of double complex legal （composite process and phase composition, the former is ＂mechanization professional qualification and composite hydrothermal method＂, the latter is ＂nanometer phase composite with ultrafine powder ＂） was adopted to change the particle size, dispersion and dispersion stability of ultra-fine calcium carbonate, using the dispersible nano-A1OOH to modify superfine calcium carbonate. Characterization of modification effect of ultra-fine calcium carbonate is transmittance, grain size analysis and SEM. The results show that nano-AlOOH particle size decreased significantly and distributed evenly, with high dispersion stability, well dispersed in the coating. When water fluid temperature was 120 ℃, reaction time was 180 min, filling degree was 50%, the molar solubility of superfine calcium carbonate was 0. 4 mol/L, the mole ratio was 3 ： 1, modification of ultra-fine calcium carbonate bad the best results.