KH-570改性纳米二氧化钛的制备及其分散性研究

Studies on Preparation of KH - 570 Modified Nano - Titanium Dioxide and Its Dispersibility

以乙醇为分散介质,采用γ-甲基丙烯酰氧基丙基三甲氧基硅烷(KH-570)对纳米二氧化钛进行化学改性,研究了KH-570用量、反应时间和反应温度对TiO_2接枝率和亲油化度的影响;采用红外光谱(FT-IR)和激光粒径分析(DLA)等手段表征了KH-570改性TiO_2粒子的结构及其分散性。结果表明:KH-570成功接枝到TiO_2表面。当KH-570用量为TiO_2的15%(质量分数),反应温度为60℃,反应时间为6 h时,改性效果最好:接枝率达到8.9%,亲油化度达到56%;与未改性的TiO_2相比,KH-570改性TiO_2的平均粒径明显减小,分布变窄。

The surface of nano -TiO2 was chemically modified using y -methacryloylpropyl triethoxysilane （KH -570 ） in ethanol medium. The influence of dosage of coupling- agent KH- 570, treatment time, and temperature on the grafting degree and-the lipophilic degree were studied. The structure and the particle size distribution of the prepared samples were characterized by FT-IR and dynamic light scattering （DSL）. The results showed that the KH -570 was successfully grafted on the surface of TiO2. The grafting rate could reach 8.9% , and lipophilic degree 56%, when KH - 570 was 15%, and treated at 60 ℃ for 6 h. The particle size and distribution of the modified TiO2 particles in the ethanol condition was obviously lower and narrower as compared with that of original TiO2 particles.