| The processability of conductive polyaniline in common organic solvents greatly expand the practical application of polyaniline. However, considering environmental problems caused by organic solvents, the research on water processing polyaniline is of great theoretical and practical significance. At present, the preparation of water-soluble polyaniline has made some progress, but the research of film has little reports. Spread coating or direct casting of the most water-soluble polyaniline are still intractable. In this dissertation, water-soluble PAn-g-mPEG copolymers doped with two kinds of protonic acid——hydrochloric acid and self-made methoxy poly (ethylene glycol) benzene sulfonic acid (MPEGBSA) were prepared by chemical oxidative copolymerization. The effect of oxidant consumption, velocity of adding An/HCl, feeding times on structure, solubility, film-forming ability and conductivity of the copolymer films were discussed systematically. The effect of molecular weight of MPEGBSA on the inherent viscosity of PAn-g-mPEG, microstructures, resistivity against water, thermal stability and conductivity of the copolymer films were also studied comprehensively. A soft and smooth conducting polymeric film can be obtained directly by casting the stable aqueous dispersion of PAn-g-mPEG synthesized at the optimal process condition.The electric conductivity of the HCl-doped copolymer films increased asmonomer concentration and velocity of adding An/HCl decreased. The maximum of electric conductivity of the copolymer films at room temperature may be obtained when monomer concentration was 0. 2 mol/L, the ratio of O/(MPEA+An) was 1: 1, velocity of adding An/HCl was 30 s/d. The conductivity improved as the molar feed ratio (nAn/nMPEA) increased. The maximum conductivity of copolymer film was 0.79 S·cm-1 when nAn/nMPEA was 15:1, but the film became more brittle and prone to cracking. Increasing feeding times would improve the water-solubility and film-forming ability of copolymer synthesized in hydrochloric acid, and the conductivity of copolymer films remain basically unchanged. The copolymers possessed the best solubility and film-forming ability when feeding times is five. In addition, The electronic conductivity of the copolymer film doped with hydrochloric acid decreased from 0. 43 S/cm to 9.07×10-6 S/cm when temperature increased from 20℃to 200℃.The molecular weight of methoxy poly (ethylene glycol) benzene sulfonic acid affected notably the solubility and film-forming ability of copolymers and the microstructures of the copolymer films. All copolymer films present distinct microphase separation characterized by AFM and SEM. The microstructure of the copolymer was converted from sea island to honeycomb with the length of mPEG segments of methoxy poly(ethylene glycol) benzene sulfonic acid increasing, the film-forming ability increased, and the conductivity of copolymer films first increased further reduced. The electronic conductivity increased with growing of nAn:nMPEA, it reached 0.30 S·cm-1 after doping with methoxy poly (ethylene glycol) benzene sulfonic acid of MnmPEG =1000 when nAn/nMPEA was 15: 1.The electronic conductivity of the copolymer film doped with methoxy poly ethylene glycol benzene sulfonic acid decreased from 2.11×10-2 S/cm to 9.22×10-4 S/cm when temperature increased from 20℃to 200℃. The thermal stability of the copolymer films doped with methoxy poly ethylene glycol benzene sulfonic acid were superior to the copolymer films doped with hydrochloric acid.
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