Preparation of polyphenylene film on platinum electrode in molten biphenyl medium by potential cycling method

The growth properties of polyphenylene (PP) on platinum electrode formed in molten biphenyl phase have been studied by potential cycling method. It was shown that the deposition of PP via a nucleation and phase growth mechanism was akin to the deposition of a metal onto a foreign substrate. Unlike the solution polymerization, the presence of water in the molten phase did not prevent biphenyl from electrochemical polymerization, but had a great influence on the growth rate of the film as well as the electrochemical reversibility of the resulted polymer. The influences of rotating speed of the electrode and the upper limit of cycling potential on the growth rate and the redox behavior of the polymer were also studied. The relationship between the redox charge (Q) of deposited polymer and the cyclic potential scan parameters had the simple form Q=a(n/v)exp(bEs) (a and b: constants, n: cycle numbers, v: potential scan rate and Es upper limit of applied scan potential).