Electropolymerization of DBSA-Doped Polypyrrole Films on PTFE Via an Electroless Copper Interlayer

Author(s): Prissanaroon, W., N. Brack, P. J. Pigram, J. Liesegang

Journal: Surf. Interface Anal. (2003) 35: 974-983.

Abstract:
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.