Vapour phase polymerisation of pyrrole on cellulose-based textile substrates

Conducting textiles were prepared embedding polypyrrole in natural and man made cellulose-based fibres, such as cotton, viscose, cupro and lyocell, by means of in situ polymerisation. Chemical vapour phase deposition of polypyrrole is a suitable process for producing electro-conductive composites in two steps: (a) fabric impregnation with an aqueous solution of oxidant and dopant and subsequent drying; (b) exposition to pyrrole vapour and polymerisation. Comparative morphological and structural analysis was carried out on the conducting viscose prepared with both vapour and liquid phases processes and some significant differences in the structural, calorimetric and electrical properties were highlighted, due to the different methods of preparation. Vapour phase prepared fabrics show a high uniform polypyrrole coating on the fibre surface and its partial penetration inside the amorphous zones of the fibre bulk. WAXD analysis shows that the conducting fabrics preserve the crystalline structure of the cellulose matrix, while SAXS results evidence the presence of a nanoparticle dispersion of polypyrrole in the cellulose matrix. Polypyrrole-cellulose conducting composite textiles show good performances to light exposure and washing fastness tests. (c) 2006 Elsevier B.V. All rights reserved.