Research On The Preparation And Performance Of Polypyrrole And PPY/TiO2Composites

As one of the common polymer materials, PPy has the advantages of superior conductivity, low oxidation potential, good environmental stability, ease of preparation, etc, it can be widely used in the field of electrode material, bio-sensor, anti-corrosion material, anti-static material and electro-luminescent material. Therefore, the preparation and application research of PPy and its composite material have a great significance.The method of high gravity-chemical oxidation was adopted to prepare polypyrrole particles, and the influence of different process conditions to the morphology and conductivity of polypyrrole was studied. Two kinds of preparation methods for polypyrrole/titania composite and their photocatalytic properties were researched. The main contents are as follows:(1)Under the high gravity environment, chemical oxidation polymerization was adopted to prepare polypyrrole particles. The impact of different reaction temperature, reaction time, the amount of monomer and rotating speed and other experimental conditions on the morphology and performance were researched. The results showed that the optimal reaction temperature of experiment was0℃, reaction time was30min, the pyrrole monomer concentration was0.10mol/L, rotating speed was2000r/min, the obtained polypyrrole morphology was uniform and the conductivity was higher. The feature of high gravity technology is reaction speed fast, particle size uniform, the reaction time short, and easy scaling up. In addition, the conductivity of the prepared polypyrrole by high gravity method is significantly improved.(2) Anatase TiO2was prepared by the sol-gel method firstly, then the PPy/TiO2nanocomposites were synthesized by in-situ polymerization, and photocatalytic activity of PPy/TiO2in the simulate sunlight were studied. The structure and morphology of PPy/TiO2were characterized and analyzed. The results showed that prepared PPy/TiO2nanocomposite particles appeared core-shell structure by in-situ polymerization method; and with the increasing the proportion of TiO2, the photocatalytic activity of PPy/TiO2increased at first and decreased later, and when the rate of Py and TiO2was1:100, the PPy/TiO2particles has higher activity, which the degradation rate of2.5h was over97%. The results also showed that the methanol yield was enhanced by34%for the composites in comparison with the pure TiO2. The reasons were considered that the separation efficiency of hole-electron pairs and the light adsorption scope of TiO2 were enhanced due to the introduction of PPy.(3)The different proportions of PPy/TiO2were prepared by hydrothermal method, which was characterized and tested by photocatalytic experiment. The results showed that the efficiency of degradation RhB dye by PPy/TiO2composite material improved compared with pure titanium dioxide, as the yield of reduction CO2generated to methanol was increased. When the rate of Py and TiO2was1:100, the PPy/TiO2particles had higher activity, which the degradation rate of reaction2.5h was up to89%. The results showed that the methanol yield of photo-reduction CO28h PPy/TiO2composite was318μmol/g· cat..