An Investigation on the Enhancement of Electromechanical Performance of Polymer Composites using Supercritical Carbon Dioxide for Electroactive Applications

Electroactive polymers (EAPs), also known as artificial muscles, are a type of polymer which responds to an electric field with structural or mechanical changes. However, current plastic research and manufacturing sectors are still lacking the use of EAP’s for smart applications, due to their diverse thermal, mechanical and electrical behavioural changes depending on small variations in their processing conditions. Therefore, this research investigated the effects of novel supercritical carbon dioxide (scCO2) fluid assisted polymer processing techniques on the thermal, mechanical and electrical properties of EAPs. Semi-crystalline polymer Pebax and rubber elastomer Poly(styrene-ethylene-butylene-styrene) - SEBS was chosen as the base polymeric material; and in order to enhance the electroactive properties, graphene-graphene oxide were used as filler material. The research begins with preliminary investigations of the scCO2 processing of polymers at various critical pressures. This initial study indicated that both polymers resulted in increased microphase formation producing a more homogeneous co-polymer base material and decreased the mechanical properties due to the foaming effect. In order to enhance the electroactive properties of the base polymers, graphene-based filler materials at low concentrations (