作者： Zhao, Cuijiao; Li, Zheng; Hu, Huan; Yang, Yu; Huang, Yawen; Yang, Junxiao

State Key Laboratory C*tion Base for Nonmetal Composite and Functional Materials, Southwest University of Science and Technology, Mianyang, 621010, China

 

摘要：Controllable preparation of small-sized SiO2 nanoparticles via sol–gel method remains a big challenge due to high reactivity of these nanoparticles. In this study, we demonstrated that when introducing coupling reagents, typically 3-(methacryloxy)propyltrimethoxysilane during reaction, the growth of silica nanoparticles can be inhibited to a large degree and the diameters can be kept nearly constant. Further, the minimum diameter can be greatly reduced to around 10 nm. DLS and SEM measurements indicated that the dispersion of the size of as-prepared silica nanoparticles was narrow. No obvious aggregation was found in the absence of any stabilizing reagents. FT-IR results showed that the surface of the silica was functionalized with considerably large number of vinyl groups. Further grafting experiment demonstrated that the amount of vinyl groups was adequay large for the grafting of polymers to form core–shell structures. Overall, the coupling reagents served not only as surface modifier, but also as terminator of sol–gel reaction.