A detailed study on static and dynamic mechanical properties of graphene oxide reinforced polyamide-6 composites

The excellent mechanical strength along with oxygen containing functional groups at their surfaces of graphene oxide (GO) sheets ensure very good mechanical reinforcements into polyamide-6 (PA6) composites through physical and chemical interactions. In this work, we have melt-mixed 1, 3, 5, and 7 parts per hundred ratios (phr) of GO into PA6 by a twin-screw extruder with a double extrusion process to assure uniform intermixing and minimized aggregation of GO sheets. The study of tensile properties showed around 80% improvement in yield strength values, and 37%, 38.6%, and 23.3% improvements in ultimate strength values of 3, 5, and 7 phr GO reinforced PA6 composites, respectively, over neat PA6. The dynamic mechanical analysis indicated the maximum entanglement of GO with PA6 chains at 5 phr content, whereas, an increasing trend was observed in the glass transition temperature with increasing GO content. The shifting trends in peak positions in XRD, Raman, and FTIR spectra indicated effective GO-PA6 interactions. These GO/PA6 composites promise applications in light weight automotive parts, defense equipments, electronics, and smart fabrics.