3 to 0.9 g, the size of SiO2 particles also increases continuously. From the viewpoint of chemical equilibrium, the increasing of the content of TEOS contributes to
the hydrolysis reaction to form SiO2 particles. However, the influence of TEOS is not as significant as ammonia. The reaction time also had impact on the results. The size of SiO2 particles grew with the increasing of the reaction time from 4 to 8 h. With the time increasing, the cross-linking between Si-O-Si chains strengthened, and the size of SiO2 particles became larger and larger. According to the above analysis, the controllability of the particle sizes was realized and in a certain range, the quantity of ammonia, the quantity see more of TEOS and the reaction time all had positive effect on the growing of SiO2 particles. Conclusion In this work, SiO2/GNPs hybrid material had been successfully achieved by a facile and controllable method as designed. In this process,
firstly, PAA was grafted to the surface of f-GNPs for providing reaction pots, and then KH550 reacted with abovementioned product PAA-GNPs to obtain siloxane-GNPs. Finally, the SiO2/GNPs hybrid material is produced through introducing siloxane-GNPs into a solution of tetraethyl orthosilicate, ammonia, and ethanol for hours’ reaction. The new characteristic band from FTIR indicated that those chemical reactions had been occurred as designed, and the results from SEM and TEM indicated that SiO2 nanoparticles were grown on the surface of f-GNPs successfully. Raman spectroscopy this website proved that after chemical drafting disordered, carbon atoms increased and carbon domains were destroyed. TGA traces suggested the residual weight fraction of polymer on siloxane-GNPs Rho was about 94.2% and that of SiO2 particles on hybrid materials was about 75.0% finally and the SiO2/GNPs
hybrid material we have prepared had stable thermal stability. Therefore, it was a feasible and reliable route to produce SiO2/GNPs hybrid material. Through orthogonal experiments, we also got the result that the controllability of the particle sizes was realized and the amount of selleck chemical ammonia had the most important impact on the size of SiO2 particles compared with quantity of TEOS and the reaction time. The next target of our study is to do research on the application of the hybrid material, to prepare epoxy resin composites with hybrid material, and study the influence of the SiO2 particles’ size to strengthen epoxy resin composites. Acknowledgements This work was supported by the National Natural Science Foundation of China (No. 51203062, 51302110). K. J. Yu thanks to Postdoctoral Fund Project of China (No. 2012M520995). References 1. Novoselov KS, Geim AK, Morozov SV, Jiang D, Zhang Y, Dubonos SV, Grigorieva IV, Firsov AA: Electric field effect in atomically thin carbon films. Science 2004, 306:666–669.CrossRef 2. Castro NAH, Guinea F, Peres NMR, Novoselov KS, Geim AK: The electronic properties of graphene. Rev Mod Phys 2009, 81:109–162.CrossRef 3.