Structure and Properties of Epoxy Resin/Graphene Oxide Composites Prepared from Silicon Dioxide-Modified Graphene Oxide
Jin An, Yue Zhang, Xiaojun Zhang, Mingpeng He, Zhou Jiang, Jin Zhou, Yan Liu, Xuebing Chen, Yiwen Hu, Xiuduo Song, Jinyao Chen, Tong Wu, Jian Kang, Zhihui Xie
Abstract
High Resolution Image Download MS PowerPoint Slide In this study, graphene oxide (GO) was modified via electrostatic interactions and chemical grafting by silica (SiO 2 ), and two SiO 2 @GO hybrids (GO-A and GO-B, respectively) with different structures were obtained and carefully characterized. Results confirmed the successful grafting of SiO 2 onto the GO surface using both strategies. The distribution of SiO 2 particles on the surface of GO-A was denser and more agglomerated, while it was more uniform on the surface of GO-B. Then, epoxy resin (EP)/GO composites were prepared. The curing mechanism of EP/GO composites was studied by differential scanning calorimetry and in situ infrared spectra spectroscopy. Results of tensile tests, hardness tests, dynamic mechanical analysis, and dielectric measurement revealed that EP/GO-B exhibited the highest tensile properties, with a tensile strength of 79 MPa, a 43% increase compared to raw EP. Furthermore, the addition of fillers improved the hardness of EP, and EP/GO-B showed the highest energy storage modulus of 1900 MPa. The inclusion of SiO 2 @GO hybrid fillers enhanced the dielectric constant, volume resistivity, and breakdown voltage of EP/GO composites. Among these, EP/GO-B displayed the lowest dielectric loss, relatively good insulation, and relatively high volume resistivity and breakdown voltage. A related mechanism was proposed.