The Role of Accelerators Prior to Electroless Plating of ABS Plastic

SummaryActivation of ABS plastic prior to electroless deposition is often achieved by treatment with mixed SnCl2/PdCl2 catalysts in conjunction with various accelerator solutions. The mechanism of acceleration for NH4HF2, H2SO4, NH4, OH and NaOH accelerators was investigated using electron microscopy and electron diffraction analysis of the adsorbed species. The action of all four accelerators was to convert adsorbed catalyst present as hydrolysed stannous and palladous chlorides to active metallic palladium. The catalytic activity of the ABS surface is directly related to the number of catalytic palladium nuclei created. This number depends on the amount of SnCl2/PdCl2 catalyst adsorbed, the degree of acceleration and the type of accelerator employed.