In-situ polymerization of graphene/SiO2 hybrids modified phenolic resin for improved thermal stability at an ultralow filler loading

We report a method of in-situ modification of phenolic resin (PR) on improving thermal stability with graphene/SiO2 hybrids at an ultralow filler loading. GO/SiO2 hybrids were prepared by electrostatic adsorption method and chemically reduced to RGO/SiO2 hybrids by NaBH4. The effect of in-situ modification of PR by GO/SiO2 and RGO/SiO2 on thermal stability of PR was studied. The results of SEM, XRD and FTIR showed that the hybrids and in-situ polymerization had a significant effect on improving the thermal property of PR. The TG and DTG analyses demonstrated that the thermal performance of PR in 350–500 °C was improved prominently. The T5% and T10% of 0.1 wt% (RGO–SiO2)/PR were increased by 165.56 °C and 89.23 °C compared with the pure PR, reaching 381.77 °C and 466.20 °C, respectively. Moreover, the R800°C of 0.1 wt% (GO–SiO2)/PR and 0.1 wt% (RGO–SiO2)/PR reached 69.86 wt% and 70.20 wt%, which increased by 10.75% and 11.29%, respectively, compared with pure PR. Therefore, the application of graphene/SiO2 hybrids in the in-situ polymerization modification of PR can significantly improve the thermal stability of PR and broaden its application fields.