纳米羟基硅酸镁的原位表面修饰和二次表面修饰

对纳米羟基硅酸镁粉体分别采用原位表面修饰和二次表面修饰进行表面化学修饰,在其表面引入众多有机短链和有机长链,使纳米羟基硅酸镁粉体在有机介质中有较好的相容性和分散稳定性。利用透射电子显微镜和傅立叶红外光谱仪分别表征了表面修饰改性前后纳米粉体的表面形貌和红外吸收光谱。结果表明:修饰剂与粉体表面发生化学吸附。未经表面修饰处理的纳米粉体呈纳米颗粒和纳米管/棒的团聚体;经过原位表面修饰处理的纳米粉体的分散性得到很大改善,呈局部分散的表面形貌;经过原位表面修饰和二次表面修饰,纳米羟基硅酸镁粉体在有机溶剂中得到有效分散。

In-situ and Secondary Surface Chemical Modification of Nano-scale Hydroxyl Magnesium Silicate

Surface of nano-scale hydroxyl magnesium silicate was modified chemically by using different methods and surface modifiers. The morphology of nano powder was studied by using transmission electron microscopy (TEM). The groups in molecular of nano powder is studied by using Fourier transferred infrared spectrometer (FTIR). The results show that the chemical adsorption of surface modifiers came into being on the surfuce of nano powder. The morphology of nano-scale hydroxyl magnesium silicate was changed from agglomerate to dispersion after in-situ modification and secondary modification. Once react with hydroxyl groups on surface of nano powder, the short organic chains and long organic chains of surface modifiers would not only reduce surface energy of nano-powder, buy also improve oil-soluble and stereo-hindrance of nano-powder.