Preparation and characterization of conducting copolymer films from 5-aminoquinoline and aniline

Abstract

Conducting copolymer films from 5-aminoquinoline and aniline (abbreviated PAq-An) were prepared by anodic polymerization of different molar ratios of the corresponding monomers in MeCN using cyclic voltammetry and potential step methods. Ellipsometric measurements on the different copolymers indicated that the thickness increases linearly with the anodic charge but with different efficiencies. The electroactivity of the copolymers is attributed to polyaniline in the films and increases as the ratio of aniline in the polymerization solution increases. The copolymer PAq-An(1:5) shows even better electroactivity than polyaniline films prepared under the same conditions due to the higher polymerization efficiency and stability of the former films. Analysis of the spectroelectrochemical measurements in acid solutions showed that the redox peaks of the copolymer PAq-An(1:5) are composed of two consecutive redox processes. Models for the redox processes are proposed to analyse the spectroelectrochemical transient behaviour of the copolymer.