Preparation,Characteristic And Structure Research On Organic Acid Doped Polyaniline

In this paper, three kinds of organic phosphoric acid doped polyaniline were synthesized by chemical oxidation polymerization. The effects of the factors on the yield and resistivity of polyaniline were studied by single factor method. The structure and properties of the products were characterized by IR,TG and TEM. The main contents are as follows.Choose the three different organic phosphate that hexamethylene diamine tetramethylene phosphate (HDTMPA), phosphoryl glycolic acid (HPAA) and hydroxyl ethylidene second phosphoric acid (HEDP) as doping acid, aniline (an) as monomer, ammonium sulfate (APS) as the oxidant. using oxidation polymerization method to prepare three different organic phosphoric acid doped polyaniline. The effects of reaction time, reaction temperature, reaction time, oxidant dosage and organic acid dosage on the yield and resistivity were studied.The optimum reaction conditions for the hexamethylene diamine tetramethylene phosphate are as follows, reaction time was 1 hour, the reaction temperature is 5 degrees, ammonium sulfate dropping time is 60 minutes, aniline and ammonium sulfate material mass ratio is 1:1.1, aniline and hexamethylene diamine tetramethylene phosphate of mass ratio is 1:1.4. The sample resistivity is 30.843 cm and the mass is 4.4 2g.The optimum reaction conditions for the two phosphoric acid are as follows, reaction time is 2 hours, the reaction temperature is 60, the ratio of aniline and ammonium is 1:1, and the ratio of aniline and ammonium is 1:1.4. The sample resistivity is 50 cm and the mass is 5.25 g.The optimal preparation conditions of phosphoryl glycolic acid are as follows, reaction time is 1 hours, the reaction temperature is 60, the ratio of aniline and ammonium is 1:1.0, the ratio of aniline and ammonium is 1:1.4. The sample resistivity is 1.507 cm and the mass is 4.91 g.Study on a variety of different doped polyaniline in isopropanol, methyl ethyl ketone solvent solubility, as well as the resistivity at 100 DEG,150 DEG,175 DEG and 200 DEG and under different temperature treatment is half an hour after the changes. The results show that the doped polyaniline in isopropyl alcohol and methyl ethyl ketone solvent solubility of about 0.8% to 2.7%, exhibit low solubility. This is mainly because of the interaction between chain and rigidity of the molecular chain of polyaniline internal strength as a result of the. When temperature prior to 175 DEG, resistivity with temperature increases slowly, when the temperature is higher than 175 DEG, resistivity increases abruptly. At this time of doped polyaniline is no longer conductive performance. This is because the increase in temperature will destroy the structure of the internal molecular chain of the doped polyaniline and thus increase the resistivity.Using Fourier transform infrared spectroscopy, transmission electron microscopy, X ray diffraction and thermogravimetric analysis, the results show that the molecular structure of the organic phosphate doped polyaniline is a kind of linear polymer with a head end connection. The thermal decomposition process is divided into two steps, the first step is evaporation of the water molecules, the second step is prolapse of the proton acid doped polyaniline molecules.