A simple approach to develop conductive poly(methyl methacrylate)-reduced graphene oxide composite with segregated network

In-situ methods are highly desirable for the development of segregated conductive composites. We demonstrate a benign and simple method for developing segregated conductive poly (methyl methacrylate)/reduced graphene oxide composites by incorporating two-step in-situ reduction of graphene oxide (GO) with poly(methyl methacrylate) (PMMA) microspheres. First, a one-pot method is demonstrated that involves the synthesis of positively charged PMMA latex followed by in-situ hydrazine reduction of negatively charged GO. In the second step, thermal reduction at 150 °C is used to increase the reduction level of GO. As a result of two-step reduction of GO, the obtained composite exhibits good correlation between their structural, morphological, thermal, and electrical properties. Compared to PMMA matrix, 4 wt % composites formed after in-situ reduction using hydrazine (PMMA-rGO-H) and two-step method (PMMA-rGO-HT) exhibit approximately 10⁸ and 10⁹ fold increases in electrical conductivity, respectively. Further, the percolation threshold for conduction is 1 wt%, indicating the generation of segregated conductive networks.