Preparation and properties of reduced graphene oxide/polyimide composite films

We have successfully prepared reduced graphene oxide/polyimide (RGO/PI) composite films by solution blending method and thermal annealing. The effects of contents of graphene oxides (GOs) and different anneal temperatures were mainly investigated. The oxygen-containing groups on GOs' surface can lead to the formation of hydrogen bonds between GO and PI, which are benefit for GO to disperse in PI uniformly and improve PI properties. The coefficient of thermal expansion decreased drastically from 15.46 mu m/(m center dot degrees C) to 3.94 mu m/(m center dot degrees C) within the range of 100-300 degrees C, and the glass transition temperature increased. These improvements can help RGO/PI films resist the high temperature when preparing photoelectric devices and get high-performance flexible photoelectric devices. The elastic modulus of RGO/PI films increased slightly, and tensile strength of RGO/PI films remained the same, while the elongation at break decreased.