Preparation and characterization of solution-processible polymer-grafted reduced graphene oxide by a radiation technology

In this research, we demonstrate that polyvinylpyrrolidone-grafted reduced graphene oxide (PVPrGO) with solution processibility can be easily produced by using a radiation technique at room temperature without any harmful reducing agent. The graphene oxide (GO) obtained from graphite flakes using a modified Hummer's method was modified through a carbodiimide-mediated coupling reaction with 4-aminostyrene to bring in polymerizable double bonds. The modified GO (MGO) was dispersed in a monomer solution of N-vinylpyrrolidon (NVP) in DMF, and the resulting mixtures were then irradiated with a γ-ray at room temperature to obtain a polymer grafted reduced graphene oxide (PVPrGO). The analytical results verified that PVPrGO is successfully produced via γ-ray irradiation-induced reduction of MGO and simultaneous graft polymerization of NVP, and its properties depend on the absorbed doses and monomer concentrations. Furthermore, the evaluation of the solution-processed thin film reveals that PVPrGO could provide the full-cover uniform thin film with a good electrical conductivity, overwhelming those of conventional graphene nanoflakes (GNFs). •Solution-processable PVP-grafted reduced graphene oxide (PVPrGO) was developed.•PVPrGO was successfully produced by in-situ radiation-induced reduction and graft polymerization.•PVPrGO provided the full-cover uniform thin film superior to conventional graphene nanoflakes.