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SPONSOR REFEREE: Takekiyo Matsuo, Osaka University, JapanConducting polymers have recently become of interest as materials for secondary batteries, electrochromic elements, transistor sensors, etc. , in both basic research and for commercial development. A number of different polymerization procedures have been developed to suit the monomers used.Since most conducting polymers are insoluble or intractable, there have been few reports concerning the elucidation of their structures. Kovacic et al.' are the only group who have characterized insoluble conducting polymers. They characterized poly(p-pheny1ene)s (PPP's), made by the reaction of e.g., benzene with a metal halide catalyst-oxidant system, using Fourier-transform infrared spectroscopy,' cross polarizationlmagic-angle sample spinning (CP/MAS) 3C-NMR2, and laser desorption/Fourier-transform mass spectrometry (LD-FTMS).**' They found that LD-FTMS provided a more complete understanding of the chemical compositions of PPP's than FT-IR andThe laser desorption ionization technique has been the only mass spectrometric method employed for insoluble polymers, because other ionization techniques require the sample to be dissolved.In spite of the fact that the field desorption (FD) method6 had been neglected as an ionization technique for insoluble polymers for this reason, we have developed a loading method which enables us to measure FD mass spectra of insoluble polymers. Having noticed the conductivity of the carbon-whisker-emitter, we have tried to use it as the anode for electrochemical polymerization, which is currently used as one of the effective procedures for preparing conducting polymers. The loading method described below is a new and simple method, which enables acquisition of FD-MS spectra of electrochemically polymerized insoluble conducting polymers. This paper describes the outline of the above procedure and a typical result for the electrochemically polymerized aniline, thiophene and dibenzo 18-crown ðer. CP/MAS-13C-NMR. EXPERIMENTAL Simultaneous polymerization and loadingAniline. An FD emitter with carbon whiskers on tungsten wire of 10pm diameter and a titanium Author to whom correspondence should be addressed. cylinder of 4.5 cm diameter were used as the anode and cathode, respectively, for electrochemical polymerization, as shown in Fig. 1. The electrolyte was an aqueous solution of 2 N perchloric acid containing 1 mol/L of aniline. Only the filament part of the FD emitter was immersed in the solution during polymerization. The voltage applied between the anode and cathode was 1.5 V. After polymerization of aniline and simultaneous loading of polyaniline on the emitter, the emitter was washed with distilled water and dried in a vacuum.Thiophene and dibenzo 18-crown 6-ether. Instead of the titanium cylinder, a gold-sputtered polyester film (2.5cmx7cm) was used as the cathode for electrochemical polymerization. The electrolyte was nitrobenzene containing thiophene or dibenzo 18-crown 6-ether (0.6 mol/L) as the monomer and tetrabutylammoniumtetra...

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