双亲性纳米TiO_2复合粒子的制备与研究

Preparation and research of amphiphilic nano-TiO_2 composite particles

采用疏水型硅烷偶联剂KH570表面接枝改性纳米TiO2,引入化学键结合的不饱和双键,再通过无皂乳液聚合法合成双亲性聚丙烯酸(PAA)-g-硅烷偶联剂KH570-g-纳米TiO2复合粒子。研究了偶联剂用量对纳米TiO2粒子分散性以及聚合条件对聚合物接枝率变化和微观形态的影响。红外光谱和热重测试分析结果表明,纳米TiO2表面偶联剂接枝率为7.62%,聚合物接枝率达61.3%;透射电镜观察表明,偶联剂处理使纳米TiO2的亲油性和分散性均提高,聚合物接枝后的复合粒子能够在有机溶剂中分散均匀且粒径增加至30nm左右。

Used hydrophobie silane coupling agent KH570 to modify nano-TiO2 ,introduced unsaturated double bond as active site, and then through soap-free emulsion polymerization prepared amphiphilic PAA-silane coupling agent KH570- nano-TiO2 composite particles. The influences of coupling agent dosage on the nanoparticle dispersion, and polymerizing conditions on grafting effectives and the morphology of the copolymer were investigated. Infrared spectroscopy and thermo- gravimetrie analysis results showed that the grafting rate of coupling agent on the TiO2 surface and the grafting efficiency of polymer were 7. 62% and 61. 3% respectively. According to transmission electron microscopy analysis, both lipophilicity and dispersion of the nano-TiO2 was improved by coupling agent treatment, the composite particles can disperse uniformly in organic solvents and the particle size increased to 30nm after polymer grafting.