Performances and properties of intrinsically conductive cellulose-polypyrrole textiles

In the past, semiconductive textiles including yarns and fabrics, have been produced by incorporating conductive fillers (particularly carbon, metal powder or conductive polymers) into the fibre structure or by coating fibres with metals or thin films of conductive polymers. Incorporation of large amounts of conductive fillers results in a deterioration of mechanical properties and processing problems of the fibres. Conductive polymers, such as polypyrrole (Ppyr), deposited on textile substrates, are highly susceptible to oxidation and abrasion. Recent research carried out in our laboratories, shows that polypyrrole can be embedded in natural and man made cellulose-based fibres, such as cotton, viscose, cupro and lyocell, by means of internal polymerisation taking place in the amorphous region of the fibres. In this work, pyrrole was applied by simple finishing process at room temperature from an aqueous solution of the monomer that penetrates into the fibre similarly to a non-reactive dye. Subsequent polymerisation caused its permanent insolubility in the internal fibre structure, leading to high levels of fastness to washing and to light exposure, without significant modification of the mechanical properties. This low cost technological application is of particular interest for developing new technical apparel, such as antistatic fabrics for work clothing, sportswear, heating and cooling equipment, etc.