Effect of surface roughness on the adhesion of electrolessly plated platinum to poly(ethylene terephthalate) films

Poly(ethylene terephthalate) films were treated with aqueous sodium hydroxide solutions of different concentrations for various times. The rate of weight loss increased with the addition of a swelling agent (methylene chloride) or a cationic surfactant. The surface roughness of the treated films was determined from atomic force microscopy (AFM) and pore diameter was obtained from scanning electron microscopy (SEM). In general, surface roughness was found to increase with increasing weight loss for the treated films. A maximum roughness was obtained for samples with a weight loss of approximately 15-20%, beyond which the roughness of the samples decreased. The addition of methylene chloride and surfactant resulted in an almost two-fold increase in the roughness for all treatment times investigated. The adhesion of electrolessly plated platinum film was dependent on the contact area produced by chemical treatment. Treatments producing smaller diameter pores of greater depth gave better adhesion.

Keywords:

• Polyethylene Terephthalate
• Roughness
• Atomic Force Microscopy
• Adhesion
• Electroless Plating
• Surface Modification