Microspheres of conducting poly(N-methylaniline)

Microspheres of conducting poly(N-methylaniline) were obtained by a potential-sweep polymerization of N-methylaniline in I M HClO4 solution. The average diameter of the microspheres grown from 0.8 M monomer concentration by sweeping potential at 50 mV s(-1) for 12 cycles was 1.9 mum. The size of microspheres could be controlled by changing several experimental parameters including scan rate, monomer concentration and cycle number. Among different acids used for polymerization process, only HClO4 and HBF4 showed ability of microspheres formation. The increase in size of alkyl group at N-position of aniline ring tended to inhibit the growth of microspheres. The formation of microspheres probably occurs through oligomer-coupled polymerization process.