Covalent functionalization of graphene using polyacryloyl chloride and performance of functionalized graphene–epoxy nanocomposite

A facile approach to functionalize mild acid treated exfoliated graphite nanoparticles (GnPs) was established using poly (acryloyl chloride) (PACl). The reaction between the acyl chloride groups of PACl and the hydroxyl group of mild acid treated GnPs (AGNPs) facilitated the formation of “ester linkage.” The remaining –COCl groups of PACl were covalently bonded with epoxy to form the hybrid nanocomposite. Structure of GnPs was not perturbed upon mild acid treatment. Successful functionalization was confirmed via thermal stability and morphological observations. The structural aspects and properties of the nanocomposites were evaluated via spectroscopic measurements, thermo-mechanical analysis, and scanning electron microscopic observations. Improved interfacial adhesion between epoxy and functionalized GnPs was evaluated via SEM. The nanocomposite exhibited an enhancement of mechanical properties at lower filler content (1.0 wt%), which resulted in an increase in flexural strength and flexural modulus by 15 and 22%, respectively. POLYM. COMPOS., 39:3119–3128, 2018.