Electroless Plating Catalyst Performance of a Cationic Moiety Bearing Palladium Complex

Abstract

Conventionally, in the electroless plating of resin, surface modification has been necessary to generate carboxylate moieties that enhances palladium catalyst adsorption. To further enhance palladium adsorption, a variety of Pd(II) amino acid complexes were synthesized, which bear a cationic pendant group with affinity for the carboxylate generated on the resin, and performance as an electroless plating catalyst evaluated. The Pd(II) complexes were characterized using UV-vis spectroscopy, revealing chelation of the amine and carboxylate groups of amino acids to Pd(II). For the Pd(II) complexes of Arginine or Lysine, affinity of the cationic pendant groups to resin surface carboxylate groups was suggested by enhanced Pd adsorption, c.a. 80 fold increase compared to complexes without cationic moieties. Furthermore, even under mild surface modification conditions with 0.5 mol/dm3 KOH, the Pd(II) complexed with Arginine or Lysine displayed performance as a electroless Ni catalyst, allowing for electolytic copper plated laminates of 1 kN/m adhesion strenghth.