摘要：为了提高纳米TiO₂粉体的亲油性和光催化性,采用溶胶-凝胶法制得纳米TiO₂粉体,经γ-(甲基丙烯酰氧)丙基三甲氧基硅烷(MPS)改性后,通过聚丙烯酰胺(PAM)在MPS-TiO₂粉体表面进行原位接枝聚合,制得基于共价键结合的PAM-MPS-TiO₂复合光催化剂,采用红外光谱、扫描电镜、X射线衍射、分散性实验和光催化实验等分析手段对改性前后的TiO₂粉体进行表征。结果表明,改性后TiO₂粉体的亲油性显著增强;在有机溶剂中的团聚现象减少,分散性提高;与纯TiO₂粉体相比,MPS-TiO₂粉体表现出较高的光催化活性,PAM-MPS-TiO₂粉体次之,经紫外光照2 h,二者均可将甲基橙几乎完全降解去除。

关键词：二氧化钛；聚丙烯酰胺；接枝；表面改性

Abstract： To improve the lipophilicity and photocatalytic of TiO₂nano-powders，TiO₂ nano-particles prepared by sol -gel method were modified with γ-（methacryloyloxy） trimethoxysilane （MPS）. Polyacrylamide（PAM） were grafted onto the surface of MPS-TiO₂ particles by in situ graft polymerization. The covalently bonded PAM -MPS -TiO₂composite photocatalysts were prepared. The samples were characterized by IR，SEM，XRD， dispersion experiments and photocatalytic experiments. The results show that the modification of TiO₂ powders can significantly enhance the lipophilicity. The agglomeration in an organic solvent is reduced and the dispensability is improved. Comparing with pure TiO₂ powders， the photocatalytic activity of MPS-TiO₂ powders is higher， PAM-MPS-TiO₂ powders follows. After illuminating 2 h by ultraviolet， methyl orange can almost be degradated completely by the 2 kinds of photocatalysts. 

Keywords： titania； polyacrylamide； graft； surface modification