Construction of super resilience graphene composite aerogels with efficient oil-water separation and formaldehyde removal, and its application for high performance urea-formaldehyde foam

Abstract

Graphene aerogel (GA) holds great potentials for treating oil-water mixtures and formaldehyde removal, while the fragile mechanical performances restrict its further development. Herein, epoxy terminated poly-(dimethylsiloxane) (PDMS) and polyurethane (PU) were grafted onto the amine-functionalized carbon nanotube (CNT) surface (CNT-PDMS-PU) sequentially, and multifunctional CNT-PDMS-PU@GA (CPPGA) was prepared through hydrothermal self-assembly and freeze-drying. Due to the tailored strong interfacial bonding, CNT-PDMS-PU acted as threads to stitch GO sheets together, and CNT-PDMS-PU was intercalated into GO layers to avoid serious restacking, constructing interconnected porous network with large specific surface area for CPPGA. Thus, enhanced compressive strength (256.13 kPa) and recoverability (90 % compressive strain), efficient oil-water separation, and excellent formaldehyde adsorption capacity (523.32 mg/g) based on chemical-physical adsorption effect were achieved for CPPGA. Besides, CPPGA powder was introduced to urea-formaldehyde (UF) prepolymer resin to prepare UF/CPPGA composite foam, which exhibited very low free formaldehyde emission and durable hydrophobicity with low water absorption ratio, showing promising application prospect in the field of building insulation. Such mechanically robust multifunctional composite graphene aerogel further burgeoned research interest for practical application.