Effect of surface pretreatment on the polypyrrole coating of acrylonitrile butadiene styrene. Part A: Synthesis and characterization

Abstract

This paper investigates the synergistic effects of a two-step surface modification approach on acrylonitrile butadiene styrene (ABS) plastics. The first step involves a mechanical grinding pretreatment followed by chemical etching in sulfuric acid and hydrogen peroxide, which increases surface roughness and enhances the wettability of the ABS surface. The second step focuses on the chemical synthesis of polypyrrole (PPy) on the pretreated ABS, demonstrating improvements in PPy surface roughness and adhesion after grinding and chemical etching. Adhesion tests reveal a significant increase from 0 % (PPy on untreated ABS) to 66 % (PPy on the grounded ABS) and ultimately to 100 % (PPy on the grounded ABS after chemical etching). This research is dedicated to a comprehensive exploration of the fundamental mechanisms, substantiated by a rigorous analysis involving X-ray photoelectron spectroscopy (XPS) examination, scanning electron microscopy (SEM) and contact angle measurements. Furthermore, the electric conductivity of PPy coatings is enhanced through electrochemical doping of PPy using dodecyl sulfate anions (DS/PPy/ABS) and the incorporation of silver particles (Ag/PPy/ABS). Raman spectroscopy demonstrates the Surface-Enhanced Raman Scattering (SERS) effect of silver particles on PPy coatings, showcasing their interaction. X-ray diffraction (XRD) confirms the enhanced crystallinity of DS/PPy/ABS, aligning with increased conductivity after electrochemical doping with DS anions.