Electrochemical deposition of zinc-polystyrene composites in the presence of surfactants

The electrochemical codeposition of polystyrene particles and zinc on a rotating cylinder electrode was investigated. Rheological measurements indicate strong aggregation of the PS particles in the zinc deposition electrolyte. Addition of cetylpyridinium chloride, a cationic surfactant, prevents aggregation and enhances polystyrene codeposition. Other surfactants also increase suspension stability, but diminish polystyrene codeposition, irrespective of their charge. Hence, the surfactant charge does not affect polystyrene codeposition. The variation of polystyrene incorporation with the amount of suspended polystyrene, current density and electrode rotation speed signifies that polystyrene codeposition with zinc is determined by the competition between particle removal forces and particle adhesion forces at the cathode surface. The effect of the surfactants can be related to changes in surface roughness of zinc due to surfactant adsorbed on the electrode. Cetylpyridinium chloride behaves differently from the other surfactants, because it is reduced at the cathode.