Direct electroplating of nickel on ABS plastic using polyaniline–silver surface composite synthesized using different acids

Abstract

Nickel coating was directly electroplated on acrylonitrile butadiene styrene (ABS) plastic substrate using a new method. The substrate surface was first coated by thin polyaniline film, then silver particles were deposited on the surface in order to improve the electrical conductivity. Three different acids (perchloric, nitric, and sulfuric acid) were used to synthesize the primary polyaniline film. The method adopted in the present study was not based on incorporation of silver particles within the polyaniline matrix; rather, the silver was deposited on the substrate surface. The electrical conductivity of the samples was increased to a level high enough for direct electroplating of nickel. The sample synthesized using nitric acid showed the finest grain size (1.57 µm) and greatest thickness of the final nickel coating (57 µm). The sample synthesized using sulfuric acid exhibited the lowest electrical resistance (0.008 Ω). In addition, the nickel coating deposited on the surface of the sample synthesized using perchloric acid exhibited the strongest adhesion to the substrate (5B according to ASTM standard).