In situ exfoliation and surface functionalization of graphene oxide for epoxy composites with improved thermal and mechanical properties

Abstract

Wet mixing and solvent evaporation were used to prepare in situ exfoliation and surface functionalization of graphene oxide (GO). The structure and composition of diglycidyl 7‐oxabicyclo[4.1.0]heptane‐3,4‐dicarboxylate (TDE85) functionalized GO (TDE85‐GO) were characterized. A thorough investigation was done into how surface functionalization affected the shape and dispersion of GO as well as the mechanical and thermal performance of the TDE85‐GO/epoxy composites. TDE85‐GO was evenly distributed throughout the matrix as a result of the special preparation method and excellent interfacial interaction between the functionalized GO and epoxy. By incorporating 0.5 wt% of TDE85‐GO, the molecular weight between crosslinks decreased from 435.1 to 182.0 g/mol, and the glass transition temperature significantly increased by 45.7°C from 148.8 to 194.5°C. The tensile strength, Young's modulus, and elongation at break increased by 18.3%, 3.7%, and 29.9%, respectively. Moreover, thermomechanical and water resistance properties have also been improved. This approach is a workable one to produce high‐performance structural composites. This approach represents a practical strategy for developing high‐performance structural composites.Highlights In situ exfoliation and surface functionalization of graphene oxide. Glass transition temperature increased by 45.7°C with 0.5 wt% of TDE85‐GO. Tensile, thermomechanical, and water resistance properties were improved.

In Situ Processing to Achieve High-Performance Epoxy Nanocomposites with Low Graphene Oxide Loading

“…Xue et al achieved the acceptable dispersion of GO into epoxy resin by the surface modification of GO by applying wet mixing and solvent evaporation, which is not ecofriendly. At first, they directly mixed the aqueous GO dispersion with the TDE85/N,N-dimethylformamide (DMF) solution to prevent irreversible agglomeration [20]. In the case of thermosetting polymers, the best practical approach can be in situ polymerization, which consists of mixing nanoparticles with pre-polymers or monomers, achieving a proper dispersion, and then polymerizing them.…”