Electrochemical Polymerization Of β-Naphthalene Sulfonic Acid In Mixed Electrolytes Containing Boron Trifluoride Diethyl Etherate

The electrochemical syntheses of conducting polymers were usually preformed in neutral organic solvents or in aqueous solutions. In these media, the oxidation potentials of many aromatic monomers were so high that cannot be successfully polymerized. It is well known that the oxidation potentials of aromatic or heteroaromatic compounds in boron trifluoride diethyl etherate (BFEE) are much lower than those in the neutral electrolytes. This disseratation was focused on the electropolymerization of β-naphthalene sulfonic acid (β-NSA) in the mixed electrolytes of BFEE and trifluoroacetic acid (TFA) or sulfuric acid (SA). 1. β-naphthalene sulfonic acid has been electrochemically polymerized in a mixed electrolyte of boron trifluoride diethyl etherate (BFEE) solution and sulfuric acid(SA). As-grown poly(β-naphthalene sulfonic acid) (PNSA) film was completely soluble in water and usual polar organic solvents such as methanol , alcohol and partly soluble in acetone. Infrared spectra studies indicate that the polymer was formed by C-C coupling at the 5,8 positions of β-NSA ring.2. β-naphthalene sulfonic acid has been electrochemically polymerized in a mixed electrolyte of BFEE solution and trifluoroacetic acid (TFA). As-formed PNSA film is a flat powdery film with weak strength. The film is in doped state and blue dark in color and has a conductivity of 0.95 S /cm. The polymer can be partly (~70%, by weight) dissolved in methanol or ethanol. The PNSA prepared in this system had a relative strong fluorescence.3. Electrochemical impedance Spectroscopy(EIS) studies indicate that the PNSA film exhibits the features of solid polymer electrolytes.