纳米二氧化硅的表面改性研究

以γ-缩水甘油醚丙基三甲氧基硅烷(GPTMS)对酸催化水解正硅酸乙酯(TEOS)聚合得到的纳米二氧化硅胶粒表面进行接枝改性,用激光粒径仪测定二氧化硅颗粒的粒径,并用透射电子显微镜(TEM)观察了改性前后二氧化硅胶粒的分散状况,采用傅立叶红外(FTIR)光谱法对改性前后的二氧化硅粉体进行了分析,通过热失重分析(TGA)法对GPTMS接枝改性二氧化硅胶粒表面的接枝度进行分析计算,同时对颗粒溶胶的ζ电位进行了测试,结果表明:改性后二氧化硅胶粒分散性大大提高,硅烷偶联剂浓度对接枝度有显著影响,当GPTMS的浓度为1mL/S iO2(g)时,接枝度达到最大,且颗粒表面的物理化学性能发生显著变化。

Study on nano- silica colloidal particles surface modification

Acid catalyzed silica colloidal particles formation were initiated by hydrolyzing tetraethyl orthosilicate(TEOS).These silica colloidal particles surface was gratfed and modificated by 3-glycidoxypropyltrimethoxysilane(GPTMS).Silica particle diameters were measured by laser particle size analyzer,and the dispersed state was observed by scanning electron microscope(SEM).The modificated and unmodificated silica powder were analysed with FTIR.Grafting efficiencies on GPTMS-Grafted silica colloidal particles surface were analysed and caculated based on the thermogravimetric analysis(TGA) data.And then Zeta-potential measurements of colloidal particles sol were carried out with zetasizer.The results indicated that the dispersivity of modified sol particles was improved evidently.Silane coupling agents concentration have an effect on grafting efficiency and grafting efficiency reached maximum when GPTMS concentration was 1mL/SiO2(g),and surface physical chemical properties of silica particles were observably varied.