Surface Modification of Graphene Nanoparticles With Ethylene Plasma in Rotary Plasma Reactor for the Preparation of GnP/HDPE Nanocomposites

Graphene nanoparticles (GnPs) were modified by ethylene plasma in order to improve their compatibility with high-density polyethylene (HDPE). The role of the plasma-based surface modification on the mechanical and electrical properties of GnP/HDPE was also investigated. The surface modification of GnPs was conducted using an in-house constructed rotary plasma reactor excited by a high-voltage power source. Morphology of the GnPs before and after plasma treatment was observed by scanning electron microscopy and transmission electron microscopy. In general, GnP/HDPE composites made with GnPs treated by ethylene plasma exhibit the highest mechanical and electrical improvements. Polyethylene decreases its electrical resistivity up 6 orders of magnitude and increases its elastic modulus by ~40% with the addition of 8 wt% of GnPs treated with ethylene plasma.