Multi-approach synthesis of functionalized graphene oxide as reinforcement for polyethylene: Make a strong interaction

Abstract

Nanoparticles need to be well dispersed in a polymer matrix to employ their advantages. Their agglomeration may cause defects and stress concentrations, deteriorating the final properties of polymer/graphene nanocomposite. Here graphene oxide (GO) was functionalized in several ways to improve its interaction with polyethylene and dispersion. Polyethylene-grafted maleic anhydride (PE-g-MA) with strong polar groups was used as the matrix to consider a high potential of enhanced interaction with the GO nanoparticles and therefore obtain a high-performance polyolefin composite. First, GO was produced by modified Hammer’s method from graphite. The GO was aminated by phenylene diamine and named FGO. Also GO was reduced chemically to obtain CRGO and thermally to obtain TRGO and then the recent ones were amino functionalized, named FCRGO and FTRGO, respectively. In another route GO was first amino functionalized and then was reduced chemically and named FCRGO+. The synthesized nanoparticles were characterized by visual tests, FTIR, XRD, SEM, and TGA analysis. Subsequently, the study investigates the fabrication of nanocomposites using these nanoparticles at 2 wt% in the PE-g-MA matrix by solution-casting method. The nanocomposites were characterized by optical microscopy, tensile and rheometric tests, FTIR, DSC, and SEM analysis. Based on the results, FCRGO+ was identified as the optimum nanoparticle having better dispersion, improved interfacial interaction, and stronger mechanical properties. The GO functionalized nanocomposites showed up to 36% in tensile modulus, 56% in tensile strength and 70% in elongation at break as compared to those of GO nanocomposites without functionalization of GO.