Constructing hierarchical porous polyimide/reduced graphene oxide sponge as an oil-water separation material with a balanced performance in thermal stability, elasticity, and oil-adsorption

To overcome the low thermal stability of conventional polymers and the low elasticity of reduced graphene oxide (rGO) as oil-water separation materials, in this study, hierarchical porous polyimide/reduced graphene oxide (PI/rGO) sponges were prepared with SiO2, polyurethane (PU), polyether amine (PEA), and liquid paraffin (LP) templates, respectively. According to experimental results, all four types of PI/rGO exhibit ideal elasticity, wherein the PI/rGO (SiO2), PI/rGO (PEA), and PI/rGO (LP) further exhibit high thermostability and excellent adsorption capability in oil and organic solvents. This study proposed a new strategy to synthesize an oil-separation material with a balanced performance of thermal stability, elasticity, and oil-adsorption.