Strengthened epoxy resin with hyperbranched polyamine-ester anchored graphene oxide via novel phase transfer approach

This work investigated the mechanical properties of epoxy resin composites embedded with graphene oxide (GO) using a novel two-phase extraction method. The graphene oxide from water phase was transferred into epoxy resin forming homogeneous suspension. Hyperbranched polyamine-ester (HBPE) anchored graphene oxide (GO(HBPE)) was prepared by modifying GO with HBPE using a neutralization reaction. Fourier transform-infrared spectroscopy (FTIR), Raman spectroscopy, X-ray diffraction (XRD), and transmission electron microscopy (TEM) showed that the HBPE was successfully grafted to the GO surface. The mechanical properties and dynamic mechanical analysis (DMA) of the composites demonstrated that GO(HBPE) played a critical role inmechanical reinforcement owing to the layered structure of GO, wrinkled topology, surface roughness and surface area ascending from various oxygen groups of GO itself, and the inarching of HBPE and the reaction among GO, HBPE, and epoxy resin. The transferred GO(HBPE)/epoxy resin composites showed 69.1% higher impact strength, 129.1% more tensile strength, 45.3% larger modulus, and 70.8% higher strain compared to that of cured neat epoxy resin. The glass transition temperature (Tg) of GO(HBPE)/epoxy resin composites was increased from 135 to 141 degrees C and their damping capacity was also improved from 0.71 to 0.91. This study provides guidelines for the fabrication of strengthened polymer composites using phase transfer approach.