Electrical performance and stability of polypyrrole coated PET fibres

PET non-wovens were treated with intrinsically electro-conducting polypyrrole (PPy) produced by chemical oxidative in situ polymerization from pyrrole aqueous solution, using Fe3+ or S2O82- as oxidant, and different dopants. The resulting materials have different electrical performances and thermal properties depending on the thickness of the PPy coating, the amount and the type of dopant embedded into the polymer layer, the type of oxidant used and the pH of the polymerization bath. Samples were maintained at different temperatures and humidity with the aim of gathering information about the electrical performance stability in different environmental conditions. Generally, PPy shows conductivity decay when maintained at high temperature, whereas the conductivity slightly decreases when stored for a long time at cold or room temperature. Moreover, the PPy coating enhances the resistance to heat of the PET fibres (i.e. increase in melting temperature).