| Conducting polymers have attracted considerable attention because of their applications in electrochemical catalysis, sensor, capacitor, etc. "Green solvent" room temperature ionic liquids are environmentally benign, and exhibit many excellent physical and chemical properties. They play an important part in green chemistry. It may produce a new polymer with novelty properties by introducing IL into polymer frame or introducing polymer into IL. In this paper, polymer doped with IL and poly(IL) were prepared by chemical method or electrochemical method. Their micrographs, structure, properties and applications have been investigated by scanning electron microscopy (SEM), transmission electron microscopy (TEM), energy dispersive X-ray spectroscopy (EDS), X-ray diffraction (XRD), infrared absorption spectra (IR), ultraviolet visible absorption spectra (UV-vis), cyclic voltammetry (CV), and electrochemical impedance spectroscopy (EIS), etc. The main points of this dissertation are summarized as follows:(1) Polyaniline core-TiO2 shell (PAN-TiO2) nanocomposite particles with a novel croe-shell structure have been successfully sythesized in ionic liquid/water (IL/water) microemulsion in the presence of anatase TiO2 nanoparticles, and the TiO2 nanoparticles beforehand had been dispersed in OP-10 and n-butanol to weaken the strong particles agglomeration of TiO2-The PAN-TiO2 nanocomposites were characterized by fourier transform infrared spectroscopy (FTIR), ultraviolet visible spectroscopy (UV-vis), scanning electron microscopy (SEM), transmission electron microscope (TEM). SEM micrographs showed that the nanocomposites exhibited spherical morphology with particle sizes about 100 nm. The TEM result showed that the PAN-TiO2 nanocomposite had a croe-shell structure that nanocrytalline TiO2 deposited onto the surface of PAN, which was different from the reported structure of TiO2-PAN nanocomposites. Both fourier transform infrared spectra and ultraviolet visible spectra results indicate that polyaniline and nano-TiO2 particles are not simply blended or mixed up, and a possible reaction mechanism is suggested and analyzed.(2) A new type of polyphenylene, ionic liquid (IL) 1,3-methylimidazolium hexafluorophosphate substituted, has been prepared by electrodeposition on Au electrode surface via pulse galvanostatic method in l-butyl-3-methylimidazolium hexafluorophosphate solution. The obtained polymer film had a spherulitic morphology with smallest grains of around 500 nm. Infrared spectrometry revealed that polyphenylene was deposited to a certain extent. The capacitive behavior of the IL substituted polyphenylene was investigated by cyclic voltammetry (CV) and galvanostatic charge-discharge method in 0.2 mol·L-1 H2SO4 aqueous solutions or pure IL [bmim]PF6. The specific capacitance of the polymer at the charge-discharge current density of 1 mA·cm-2 equaled 206 F·g-1 in acidic aqueous solution or 164 F·g"1 in [bmim]PF6. Additionally, excellent charge-discharge cycle stability (over 85% value of specific capacitance remained after 600 charge-discharge cycles) and power characteristics of the polymer electrode were observed in both electrolytes.(3) Imidazole and 1,3-Dichloro-4,6-dinitrobenzene were dissolved in proper amount of absolute ethanol under the such condition as magnetic stirring to prepare poly(imidazolium chloride ionic liquid). The polymer was characterized by gel permeation chromatography (GPC), fourier transform infrared spectroscopy (FTIR), ultraviolet visible spectroscopy (UV-vis), scanning electron microscopy (SEM), transmission electron microscope (TEM), thermogravimetric analysis (TGA) and conductivity measurement. GPC result showed that the Mn of the polymer was 1517, and the Mw was 2543. Infrared spectrometry revealed that there exist benzenoid ring and benzene ring in the polymer chains, and the ultraviolet visible spectra result approved the conjecture about the structure of the polymer furthermore. SEM micrographs showed that the polymer exhibited spherical morphology with particle sizes about 200 nm, EDX result further confirmed the structure. The polymer has excellent thermostability under 200℃, the mass lost of the polymer is only 20% below 550℃. Conductivity of the polymer is better than the commercial polyaniline, moreover, the conductivity of the polymer can be further improved after doping.
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