Chemical and electrochemical synthesis of homopolymer and copolymers of 3-methoxyethoxythiophene with aniline, thiophene and pyrrole for studies of their gas and vapour sensing

Abstract

Herein we report chemical and electrochemical formation of poly(3-methoxyethoxythiophene) and its copolymers with aniline, thiophene and pyrrole which give highly conducting polymeric materials. These are soluble in common organic solvents in the conducting state. The response mechanism of these compounds, to a selection of gases and vapours, was investigated using two techniques: measurement of conductance and mass changes using a four probe method and X-ray fluorescence (XRF) device, respectively. Prepared films were exposed to hydrogen halides, hydrogen cyanide, halogens, monochloroacetic acid (MCAA), 1-3-5 trichloromethylbenzene (TCMB), methylbenzyl bromide (MBB), bromoacetone (BA) and cyanogen bromide (CB). These gas sensors may have advantages compared to other sensors in their ability to operate at room temperature, low concentration, stability in air, sufficient diffusion and thier selectivity. Copyright © 2001 John Wiley and Sons, Ltd.