纳米碳酸钙的改性及其在硅酮胶中的应用

Modification of nano calcium carbonate and its application in silicone sealant

采用微孔分散碳化法合成了微纳米碳酸钙(CaCO_3),通过添加油酸对纳米CaCO_3进行了表面改性,研究了改性纳米CaCO_3对硅酮密封胶性能的影响。试验结果表明,适量的油酸可以降低颗粒粒径,并能改善分散性,过量的油酸虽然能够降低颗粒粒径,但会使粉体的分散性变差;与添加普通纳米CaCO_3相比,当添加油酸质量分数为1.5%时,改性纳米CaCO_3不仅减小了所制硅酮胶的表干时间,其固化性能、拉伸伸长性能和粘接性能也得到极大改善,且纳米CaCO_3的相对最佳添加量为35%。

The microporous dispersion carbonation method was used to synthesize micro-nano CaCO3 in this paper The surface modification of nano CaCO3 was carried out with oleic acid and the effect of the modified nano CaCO3 on the properties of silicone sealant was studied. The results show that appropriate amount ofoleic acid can reduce the particle size and improve the dispersion of powder, while excessive oleic acid can reduce the particle size and deteriorate the dispersion of powder, and the optimum addition is 1.5wt%. Compared with adding unmodified nano-CaCO3, when the adding amount of oleic acid was 1.5wt%, the modified nano-CaCO3 not only reduced the surface dry time of silicone sealant, but also greatly improve the curing performance, tensile elongation properties and adhesive properties of the sealant. The best adding amount ofnano CaCO3 is 35wt%.