The Polymerization And The Study Of Doping And Conductivity Of Polyaniline

In comparison with other conjugate polymer, the prices of PAN is cheap and abundant, which can be easily polymerization, with high conductivity and a broad prospect for application. This thesis studies the structure and properties of PAN in electro polymerization and oxidized polymerization, as the subject for study and prepares the PAN and PAN/TiO₂ films.The body of the thesis is divided into 3 sections.(1) Study on of doping to the conductivity of PAN will be examined in the follow part. Through the doping tests with hydrochloric acid, carbon fiber and inorganic oxide, the effect of m-cresol on the conductivity of PAN is analyzed and the conductivity mechanism of the structure of PAN doped with different substances revealed. Consequently, PAN is obtained with good property of conductivity. Lab study shows that only under appropriate acidity (2≤pH≤4), the polymerization occurs in by way of 1,4-polymerization. The doping of TiO₂ efficiently enhances the conductivity of PAN, reaching the maximum value when thegravity between PAN and TiO2 is 5/1. At this time, the conductivity is 0.9S/cm. As a good organic mixture for strength and tenacity, carbon fiber improves the mechanical performance and processing capability of the system. The repeated doping of m-cresol also significantly enhance the conductivity of PAN. Compared with PAN came from market, the conductivity of our PAN/TiO2 film is 60 multiples than it.(2) The effect of PAN on electro polymerization will be examined in the second part. The part is studied and the conductivity mechanism of polymer chain structure and by AN and different potentials revealed. Lab test shows that the optimum density of AN is 0.1M, with the best potential being 0.6V. At this time, the conductivity of PAN and PAN/TiO2 reach the maximum, being 0.65S/cm and 0.78S/cm respectively. TEM shows that the structure obtained from PAN and PAN/TiO2 is mainly non-crystal, with small quantities of crystal. The adding of 55% TiO2 increases the conductivity of PAN system and regional crystal increases the tidiness of it, facilitating the enhancement of the conductivity of PAN.(3) The effect of contents of TiO2, different reaction time and temperature on the film structure of PAN/TiO2 as well as the conductivity is studied. By and large, including the effect of adding up TiO2 on the heat stability of PAN film. Lab tests show that the ideal conditions for us to prepare PAN/ TiO2, compound material with high conductivity are 55% of the TiO2 content, 5 hours of oxidization and oxidization reaction...