纳米碳酸钙在水中的分散

筛选出了适合于在水中分散的纳米碳酸钙，分别考察了分散机转速、分散剂种类、分散剂用量、分散时间和悬浮液浓度等因素对纳米CaCO3在水中分散的影响，优化出了纳米CaCO3在水中分散的工艺条件，即：转速为7500r／min，分散剂为PK-100，分散时间为1．5h，分散剂用量为纳米CaCO3质量的3％，悬浮液浓度为15％．结果表明，优化条件下所制得的悬浮液黏度较低，纳米CaCO3平均粒径较小，分散均匀，且贮存稳定性良好．添加了该纳米CaCO3浆液的复合建筑涂料的耐沾污性、耐洗刷性、触变性、耐水性、耐碱性和耐老化性等得到了显著改善．

Dispersion of Nanometer Calcium Carbonate in Water

A kind of nanometer calcium carbonate ( nano-CaCO3) suiting for dispersion in water is selected. The influences of several factors, including the speed of rotation, the variety and dosage of dispersing agents, dispersing time and suspension concentration, on the dispersion of nano-CaCO3 in water are investigated respectively. The technological conditions of dispersion of nano-CaCO3 in water are optimized. It is concluded that: the speed of rotation is 7 500 r/min; dispersing agent is PK-100; dispersing time is 1.5 h; dispersing agent dosage is 3% (by mass) of nano-CaCO3 ; nano-CaCO3 suspension concentration is 15% (by mass). The results show that under the optimized conditions the viscosity of the suspension produced is low and the average diameter of nano-CaCO3 is small, the dispersion is uniform and the storage stability of the suspension is good. The properties of composite architectural coatings, including dirt resistance, scrub resistance, thixotropy, water resistance , alkali resistance and weathering resistance, are improved after nano-CaCO3 suspension is added.