Overview of the preparation of pure polyaniline and conductive composites in dispersed media and by thermal processes:: from laboratory to semi-industrial scale

Intrinsically conductive polymers (ICPs) and conductive composites offer many potential industrial applications due to their conductive properties, processability and mechanical properties. Much work has been carried out to develop the synthesis and formulation of various conductive polymers. Nevertheless, polyaniline (PANI) seems to be one of the most interesting conductive polymer based on the low cost of its synthesis, its conductive properties and its thermal and environmental stability. In this paper, we describe the synthesis and formulation of conductive composites containing PANI by considering two synthetic approaches. The first one is based on the oxidative polymerization of aniline. This synthesis has been optimized from laboratory-scale to a 50 L pilot-plant reactor. After a post-doping procedure, the composite is obtained using a twin-screw extruder. The second approach concerns a core/shell synthesis (polymer matrix/PANI) procedure which allows synthesis and formulation at the same time. Conductive composites of various compositions (polymer matrix/PANI content and additives) were synthesized by both of these methods and the advantages and drawbacks of each of them are discussed. (C) 2006 Society of Chemical Industry.