Feasibility And Mechanism Of Electroless Plating On The Surface Of Rigid PVC

PVC surface is known difficult to be roughened and deformation is too high under conventional etching temperature of 60 80℃. These are reasons that electroplating of PVC has not been successful in practice to date.We established a new pre-etching method. Poly(vinyl pyrrolidone-vinyl acetate) is added into THF-H)2O solution. With such a pre-etching solution, PVC sheet can be etched at 21℃ and good adhesion of uniformly deposited nickel to PVC surface is achieved in laboratory experiments.Combining ATR technique, scanning electron microscopy technique and weight analysis, it is known that copolymer molecules are adsorbed to PVC surface in pre-etching process by the interaction of pyrrolidone side group with PVC surface. A portion of copolymer adsorbed is removed by etching, consequently uniformly distributed cavities are formed on PVC surface. Pyrrolidone groups on the copolymer molecules which are left on PVC surface after etching are found to be hydrolyzed into -NH(CH₂)₃COOH groups. PVC surface wettability is believed to be enhance by those carboxyl groups.In the process of pre-etching copolymer molecules and THF molecules are both adsorbed onto PVC surface. Copolymer concentration, pre-etching time and pre-etching temperature are found to have inter-related influence on both kinds of adsorption. Pre-etching temperature of 21℃ is considered optimum condition to minize the influence...