Synthetic Metals, 41-43 (1991) 837-842 837 HIGH PRESSURE CONDUCTIVITY AND MORPHOLOGY OF CONDUCTING POLYMER COLLOIDS

INTRODUCTION The development of conducting colloids stemmed from applications driven needs for proeessable conducting polymers. Because conducting polymers are aggregated in nature, due to their conjugated backbones, the preparation of colloidal systems of these aggregates is an attractive approach to by-passlng the intractability problem. The reason for focussing on the two particular colloidal systems studied here, polypyrrole and polyanillne, is the fact that their alr-stabillty is much better than other conducting polymers. The preparation of colloidal polypyrrole in aqueous media using commercially available water-soluble polymers as sterle stabilizers was reported earlier [1-4]. In all cases, the particle morphology was spherical and usually monodlsperse (± 15% standard deviation). The actual particle diameter obtained depends on the nature of the stabilizer, its concentration and molecular weight and varies over a range of 50-450 nm. The conductlvltles of compressed pellets or thin films fabricated from aqueous dispersions of the polypyrrole partlcles were surprlsingly high (0.1-2.0 G-l.cm-l), despite the presence of up to 10-15 wt% of the insulating adsorbed sterle stabilizer [3]. We have reported on our systems earller in various publications [5-9] with the goal of widening the spectrum of sterlc stabilizers and the detailed study of various properties of the various systems to optimize the materials for colloidal stability, high eonductlvltles and film-formlng properties. The main distinction between polypyrrole and polyanillne colloids is that the former is formed by physical adsorption ,via hydrogen bonding, of the sterlc stabilizer onto the polypyrrole partleles, and the latter is formed by