LAMELLAR CONJUGATED POLYMERS BY ELECTROCHEMICAL POLYMERIZATION OF HETEROARENE-CONTAINING SURFACTANTS - POTASSIUM 3-(3-ALKYLPYRROL-1-YL)PROPANESULFONATES

A series of self-assembling monomers, potassium 3-(3-alkylpyrrol-1-yl) propanesulfonates, are electrooxidatively polymerized from micellar so lution to afford lamellar phases of the substituted polypyrrole. The k inetics of electrochemical oxidation are quite sensitive to the concen tration of the surfactant monomer and display the effects of solvent-i nduced molecular self-assembly. The films were characterized by low-an gle X-ray diffraction, glancing angle infrared spectroscopy and X-ray photoelectron spectroscopy. The lamellar phase consists of a head-to-h ead packed of the surfactant repeat units. Consequently, the crystal r epeat distance corresponds to approximately twice the extended length of the monomer. Infrared measurements indicate that lower homologs are conformationally less ordered, in accord with the observation that th ey also give rise to broadened X-ray diffraction lines, reflecting les s positional order. The as-grown films are resistive (<10(-6) OMEGA-1 cm-1). Upon treatment with aqueous HClO4 the conductivity along the fi lms enhanced (10(-3) OMEGA-1 cm-1) imparting anisotropic conductivity which is consistent with the lamellar structure.