Electropolymerization of DBSA-doped polypyrrole films on PTFE via an electroless copper interlayer

We report on the electroless deposition of thin films of copper on poly(tetrafluoroethylene) (PTFE) and their use as substrates for electropolymerization of polypyrrole. Argon plasma-treated PTFE films were modified by silanization using N-[3(trimethoxysilyl)propyl]diethylenetriamine (TMS). The TMS-modified PTFE films were subsequently activated by PdCl2 for the electroless deposition of copper. The omission of the commonly used SnCl2 sensitization step represents a significant process enhancement with environmental and cost benefits. The surface composition of the substrate (before and after surface treatments) and overlayer films was studied using high-resolution x-ray photoelectron spectroscopy. A combination of time-of-flight secondary ion mass spectrometry and water contact-angle measurements was also used to study the PTFE surface after argon plasma treatment. The Cu/PTFE films were used as substrates for subsequent pyrrole electropolymerization in aqueous dodecylbenzene sulphonic acid (DBSA) solution. The DBSA-doped polypyrrole overlayers were successfully deposited on the Cu/PTFE surface using a constant applied potential of 1.5 V. The resulting material exhibited a doping level of 39%, determined using chemical component analysis of the N 1s photoelectron peak. Copyright (C) 2003 John Wiley Sons, Ltd.