Reduced graphene oxide synthesized by a new modified Hummer's method for enhancing thermal and crystallinity properties of Poly(vinylidene fluoride)

Abstract

A new technique based on the modified Hummer's method to synthesize reduced graphene oxide (rGO) with high purity, as well as enhanced quality and low layer stacking is presented. It aims to demystify traditional considerations made from X-ray diffraction by introducing comprehensive models to determine the number of stacked layers, as well as understand and respect the limit of the physical phenomenon involved in the technique. Poly (vinylidene fluoride) (PVDF) nanocomposites incorporated with up to 5.0 wt.% of rGO were processed via extrusion without using a compatibilizing agent. The results showed that the rGO nanoparticles display a good interface with the PVDF matrix without agglomeration. In addition, there was an improvement in the nanocomposite's stability and thermal resistance. The rGO acted as a nucleating agent, increasing the degree of crystallinity in 33% of the PVDF for all concentrations. The values of water contact angle raised from around 70° in the neat matrix to 80° in the nanocomposite. Scanning electron fractographies demonstrated the tendency of the reinforcement effect of rGO, favoring a greater ductility for cyclical loads. Finally, the results showed that incorporating rGO led to increased nanocomposite thermal performance compared to the neat polymer, revealing a promising candidate for ducts and oil pipelines.

Keywords

• Reduced graphene oxide
• rGO
• Thermal performance
• Degree of crystallinity
• Nanocomposites
• poly(vinylidene fluoride)