Reductive surface treatment of polytetrafluoroethylene with electrochemically generated radical anions of several polycyclic aromatic hydrocarbons

Electrochemically generated radical anions (R •− ) of several polycyclic aromatic hydrocarbons (R) were used for the surface treatment of polytetrafluoroethylene (PTFE). R •− works as an electron donor, which causes reductive elimination of F − on the PTFE surface. It was shown that the reduction potential of R significantly affects the rate of the reductive elimination of F − . By the reductive treatment of the PTFE surface, the contact angle of a water droplet decreased from 110° to about 60°. The contact angle change was analyzed to determine a standard rate constant of the reductive elimination ( k 0 ) with the radical anion of pyrene (Py •− ) and anthracene (An •− ), based on the Butler-Volmer model, and k 0 = 5.7 × 10 −4 and 4.6 × 10 −4 M −1 s −1 for An •− and Py •− , respectively, were obtained. Furthermore, electroless deposition of Au and Cu on the treated PTFE sheets was carried out. Due to the reductive surface treatment, the Au and Cu layer was formed more uniformly than in the case of the untreated PTFE by the electroless deposition.