In situ chemical reduction (ISCR) of graphene oxide (GO) dispersed in a polymer matrix has been regarded as an effective path to fabricate electrically conductive graphene/polymer composites due to the combination of perfect dispersion of GO in a polymer matrix and high electrical conductivity of graphene. However, there are only very limited number of reducing agents that can be applied to the ISCR process for the fabrication of graphene/polymer composites. Herein, we report a highly efficient reducing agent, 1,2-diiodoethane, which can be used in the preparation of graphene (IGO)/polyimide (PI) composites via the ISCR process. The results showed that the electrical conductivity of IGO/PI composites with 2.5 wt% of IGO was 2.22 S m−1, nearly seven orders of magnitudes higher than that of GO/PI without the addition of 1,2-diiodoethane. Moreover, the tensile strength and modulus of IGO/PI composites were increased by about 43% and 52% as compared with that of the pure PI, respectively. Furthermore, 1,2-diiodoethane and its decomposition products would not remain in the composites. The ISCR-based methodology can be extended to many other polymer composites and thus paves the way for easy and effective fabrication of conductive polymer composites.
