Preparation and characterization of high-density polyethylene/graphene oxide (HDPE/GO) nanocomposites: Experimental and computational insights

Maleic anhydride (MAH) grafting effectively enhances the interfacial compatibility between hydrophobic high-density polyethylene (HDPE) and hydrophilic graphene oxide (GO). In this study, HDPE-g-MAH/GO nanocomposites were prepared by melt blending and investigated using experimental techniques (FTIR, DSC, and TGA) combined with molecular dynamics (MD), density functional theory (DFT), and COSMO-RS analyses. MD simulations showed that MAH grafting increased the polymer–GO binding energy from about 455 to nearly 2000 kcal·mol −1 , indicating significantly improved interfacial adhesion. Hydrogen bonding between GO oxygenated groups and MAH functionalities was identified with an average O···H distance of ∼2.15 Å and an interaction energy of −4.8 kcal·mol −1 . DFT calculations revealed a reduction in the HOMO–LUMO energy gap from 9.16 eV for PE to 0.56 eV for the PE-g-MAH/GO system, suggesting enhanced charge transfer and interfacial interaction. Experimentally, MAH grafting reduced HDPE crystallinity from 41.4% to 32.1%, while GO incorporation partially restored crystallinity up to 36.2% due to its nucleating effect. TGA results showed slight improvements in thermal stability. COSMO-RS analysis further confirmed the enhanced affinity of MAH-grafted PE toward GO, demonstrating the compatibilizing role of MAH in improving nanocomposite performance.