Review on Application of Supercritical Fluids in Producing Conductive Polymeric Fibers

Conductive polymers such as polypyrrole (PPy), polyaniline and polythiophene have foreseeable use in various products such as chemical-sensors, transducers, antistatic coatings, conductive fibers and smart textiles. Supercritical carbon dioxide (SC-CO2) is a ‘green’ solvent that can be used in chemical processes. Although, none of the aforementioned polymers are soluble in SC-CO2, but precipitations take place during the polymerization. Given the fluorophilicity of SC-CO2 and the strong interaction between SC-CO2 and carbonyl groups, the unique combination of fluoroalkyl groups and carbonyl groups makes the polymers highly soluble in CO2 at moderate pressure and temperature. The blends of conductive polymers with another polymer, which are often referred to as conductive composites, are generally produced conductive fibers. As a non-toxic and environmentally acceptable solvent, SC-CO2 may also be beneficial in tailoring the properties of the composites by control of sorption and desorption processes.