Abstract: 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 dynamie 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 abvious lower and narrower as compared with that of original TiO₂ particles.

Key words: nano-TiO₂, KH-570, surface modification, lipophilic degree, particle size distribution

摘要： 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TiO2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TiO₂粒子的结构及其分散性。结果表明:KH-570成功接枝到TiO₂表面。当KH-570用量为TiO₂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TiO₂相比,KH-570改性TiO₂的平均粒径明显减小,分布变窄。

关键词: 纳米TiO₂, KH-570, 表面有机化, 亲油化度, 粒径分布