| Transparent and conducting organic (polymer) film is a sort of multiple functionalmaterials and has been the focus of scientific research recently due to itsconductivity, photoelectricity and the applications in solar battery, transparentelectrode, photoelectricity conversion and auto controls, IR reflect, thermoelectricityconversion, electromagnetism absorbance and shield, et al. In this dissertation, it isreported the preparation of conducting polymer-PANI films via the in-situpolymerization deposition of aniline on the different matrix surfaces. In the study,different steric stabilizers were used in the polymerization deposition, and influencesof inorganic and organic steric stabilizer on film morphology were compared; couplingagents were used to modify glass surface from hydrophilic and hydrophobic, to revealthe effect of the matrix surface properties on the film growth speed and its morphology.As well, PANI films were successfully deposited on PI sheet, preparing a new kind ofcomplementary functional PI-PANI complex films and investigating the film formationon other matrix but glass. Based on the experimental results, actuating force offilm-forming was analyzed, and growth mechanism and model of PANI filmsdeposited by in-situ polymerization were discussed.In detail, inorganic nanometer SiO2 as a steric stabilizer provided a steadyenvironment for the growth of films in the system of PANI dispersion polymerization,ameliorating the morphology of prepared PANI films greatly. The depth of films werewithin 3～300nm, and their conductivity ranging from 3×10-3 S·cm-1 to 1.8×10-2S·cm-1,the typic conductivity of semiconductor. The addition of nanometer SiO2 could slowerthe speed of aniline polymerization, extending the induction period, reducing thehighest temperature of reactivity solution. The lack of characteristic absorption of TiO2in FTIR spectra indicated that the steric stabilizer had not participated in thepolymerization of PANI films. XRD revealed the low crystallinity of PANI. The counterpart, micrometer scaled SiO2 cannot behave as well as the nanometer SiO2 inthe stabilization effect. With the increase of particle diameter, the induction period wasshortened and reaction speed was accelerated. But the surface of PANI films wasgranulated, and some PANI layers were attached on.Three kind of coupling agents, OTS, N-phenyl-3-aminoproplytrimethoxysilaneand 3-glycidoxypropyltrimetho xysilane were used to modify the glass surface. Incomparison with the hydrophilic glass surface, aniline cation free radical and itsoligomer absorbed on the modified hydrophobic surface with higher absorption speedand greater density of nucleation centers. The apparent quality, depth and conductivityhad been all improved, while the modification effect of OTS was most remarkableamong the coupling agents. Taking the advantage of the difference of the depositionspeed on hydrophilic/hydrophobic surface, the selective designing deposition of PANIand its application on microcircuit and micro-device is reasonable to expect.Besides of the deposition on the glass, a new type material-PI 6051 was selectedas matrix for the deposition of PANI films with in-situ polymerization, in order to getPI-PANI compound films. It was found that aniline cation free radical could absorb onPI surface easily because PI had similar surface functional group, polarity with PANI.For the same reason, PI6051 could accelerate the polymerization of aniline, shorteningthe induction period of aniline dispersion polymerization and speeding up the film'sgrowth. The prepared compound films is of high quality, whose depth could reach to123nm while the conductivity could arrive at 7.502×10-3S·cm"-1.The other feature of this research was the in-depth investigation on the growthmechanism of PANI films on glass surface. There were two direct actuating forcearoused by aniline's absorb to glass surface: one was the soakage of glass surface; theother is absorption activity of aniline cation free radical. Under the action ofhydrophobicity effect and Vander Waals force, aniline cation free radical absorbed tothe surface of glass, becoming the activity center of chain increasing. The on-lineinvestigation and characterization revealed that the growth of PANI films underwentthree stages: adsorption nucleation, growth and growth saturation. As part of theconclusion, the model of PANI films describing the in-situ polymerization depositionof the aniline were brought up.
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