Multiscale effect of graphene oxide with short carbon fiber for property improvement of room temperature vulcanized silicone rubber

Graphene oxide (GO) has been widely used as a multi-functional filler in various composites. In order to improve the properties of room temperature vulcanized (RTV) silicone rubber, the functionalized GO (FGO) was used as 2-dimensional filler with short carbon fiber (SCF) and silica particle. The effects of the FGO content on the properties of the RTV silicone rubber composites were investigated. When appropriate amount of the FGOs is added in the composite, the interfacial bonding between SCFs and silicone rubber matrix could be effectively enhanced and the properties of the composites are improved. For the composite with 0.5 phr FGO, the tensile and tear strengths are about 4.7 MPa and 21.9 kN/m, respectively. Meanwhile, the corresponding values of the composite without FGO are only 4.0 MPa and 20.3 kN/m, respectively. The above said values of the composite with 1 phr FGO are 3.8 MPa and 19.8 kN/m, respectively. In addition, the onset decomposition temperature and temperature at the highest decomposition rate for the composite with 0.5 phr FGO, both remarkably increase from 493.4 to 504.2 °C and 564.4 to 613.1 °C, respectively. The carbon frameworks (dense layer and porous layer) will form during the ablation process and play the key role in protecting the RTV silicone rubber, which leads to the reduction of the ablative rate.