| Manufactering micro/nano-structured materials with special functions are one of important topics intensively studied in nanometer technology. In recent years, there has been increased interest in studying polyaniline (PANI) mainly because of their potential applications in lightweight batteries, electrical conductivity, optical devices, transparent electrodes and electromagnetic shielding, as well as chemical and biological sensors. Moreover, the performance of PANI may be improved by its nanostructure, which has distinguished characters in conducting channels, interconnections and nanoscale dimensions. In addition, the application of polymer films is getting important owing to their light, flexibility, shock resistance and low cost. Thereby, fixing PANI on the surface of polymer substrates would bring them more sound applications, such as in disposable electronics, conductive surface, all-polymer field-effect transistor and so on. This dissertation mainly includes immobilizing nano/microstructured PANI on the surface of polymer film and synthesizing various nanostructured PANI in solution.1. Two-dimensional structured PANI was grafted on the surface of polypropylene (PP)-g-polyacrylate acid (PAA) composite films via surface oxidative polymerization. In the course of polymerization of aniline on the surface of PP-g-PAA film, the optimum reaction period was 5 h and pH value was 1. The average thickness of the grafted PANI on the surface of PP-g-PAA/PANI /composite film was about 600 nm and the maximum conductivity was about 10-2 S/cm. Moreover, PANI particles with diameter about 100-500 nm could be observed on the surface of composite film.2. Two-dimensional structured PANI was grafted on the surface of PP-g-PAA/ 1, 4-phenylenediamine (PDA) composite films via surface oxidative polymerization method. In the preparation of composite film of PP-g-PAA/PANI, PANI was firmly tethered on the PP-g-PAA/PDA films surface by reacted with PDA When the graft percentage of PANI was 1.5 wt%, the average thickness of grafted PANI on the composite film was about 0.4 μm, and the diameter of the formed PANI particles was about 150 nm. On the surface, the conductivity of PANI was 0.21 S/cm, and the water contact angle (CA) was about 80°. In addition, the PANI chains on the PP-g-PAA/PANIcomposite film could be reactivated under the action of ammonium persulfate, which then could be polymerized with other aniline monomers to increase the graft percentage of PANI on the composite film.3. Nano/Micro PANI (spherical particle, wire and ribbon) were novelly prepared on the surface of polymer (PP) film by self-assembly. The morphology and the size of PANI on the composite film could be readily controlled by tuning the molar ratio of AA to aniline. When the AA concentration was 0.11 M, the obtained PANI particles on the surface was 70-200 nm in diameter at the molar ratio of AA to aniline= 1:0.3. The PANI particles with 700-1100 nm in diameter was observed at the molar ratio of AA to aniline= 1:0.6. At the molar ratio of AA (0.07-0.3 M) to aniline about from 1:0.9 to 1:1.1, PANI nanowires with 90-140 nm in cross-section diameter and about 4 uin in length were observed. When the molar ratio of AA to aniline was about 1:1.2, the large-range PANI nanoribbons with length over 4 um, width about 600 nm and thickness about 70 nm were obtained. In addition, a great deal of PANI nanowires and nanoribbons were vertically oriented by crowding. The conductivity of the spherical particle, nanowires and nanoribbons was 1.6 X 10'2, 8.3 X 10"2, 5.7 X 10"2S/cm, respectively (the molar ratio of AA to aniline is 1:0.6, 1:1.1 and 1:1.2, respectively), when the AA concentration was 0.22 M, the PANI hollow spheres with 800 nm in diameter and 150 nm in thickness of the spherical wall were obtained on the surface of PP film with just one layer at the molar ratio = 1:1.6, when the grafting percent of PAA was 1.1 wt%. The conductivity of this monolayer PANI hollow spheres was 1.1 X 10-2S/cm.A possible forming mechanism of nano/microstructured PANI was suggested that aniline interact with AA and grafted PAA on the PP-g-PAA film would corporately form different shapes of micelles under different condition, which were then applied as the templates for the formation of different nano/microstructured PANI. Moreover, the PAA grafted on the surface of PP film would join in the forming the templates for nano/microstructured PANI.4. Three-dimensional PANI nanowires networks with high-yield were firstly synthesized through a "soft template" self-assembled with hexadecyltrimethylammonium bromide (HTAB) and oxalic acid. It was found that the diameter of the three-dimensional PANI nanowire networks could be tuned in different synthesis condition or process. When the concentration and the molar ratio of reagents,...
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