聚苯酚等导电高聚物的合成及性质

【作者】 陈传祥；

【导师】 穆绍林；

【作者基本信息】 扬州大学 ， 物理化学， 2002， 硕士

【摘要】 本论文的工作主要研究了聚苯酚与聚天青A的电化学合成和性质以及聚苯胺的“绿色”合成。 一、导电聚苯酚的电化学制备 通过循环电位扫描法、恒电位法、恒电流法以及现场可见光谱证明了在0.1mol·dm^-3。苯酚、3mol·dm^-3 NaOH和0.5mol·dm^-3 Na₂SO₄溶液中聚合在铂片上的聚苯酚膜能随着电解时间的增加而不断生长。在0.7 V（相对于Ag／AgCl／饱和KCl溶液）恒电位电解苯酚溶液获得了0.11mm厚的聚苯酚膜。在2mol·dm^-3 H₂SO₄、中性溶液和3mol·dm^-3 NaOH溶液中和在-0.95～1.35 V的电位范围内，聚苯酚膜没有电化学活性并是稳定的，它的有效电位范围依赖于pH值。聚苯酚有ESR信号，其g因子为2.0049。聚苯酚的电导率是1.2×10^-4 S·cm^-1。20℃时，聚苯酚的二甲亚砜溶液中的聚苯酚阴离子的迁移率为8×10^-9m²·s^-1·V^-1。本章提供了聚苯酚的红外光谱。 二、聚天青A的电化学合成及性质 用循环电位扫描法研究了天青A的电化学聚合。电位扫描范围为-0.2～1.3 V（相对于Ag／AgCl／饱和KCl溶液）。电解溶液由pH 6.0的5mol·dm^-3天青A和0.5mol·dm^-3 Na₂SO₄溶液组成。聚合温度控制在50℃。在pH 1.0的0.5mol·dm^-32扬州大学硕士学位论文N气504溶液中，聚天青A的循环伏安图上有一对氧化还原峰分别出现在0.38V和。23v。随着pH值从1.0升高到4.0，它们的峰电位向负电位方向移动。在上面pH值范围内的水溶液中，聚天青A具有良好的电化学活性和稳定性。聚天青A的紫外一可见光谱和红外光谱不同于单体天青A。聚天青A的红外光谱表明没有阴离子掺杂进入氧化态的聚天青A中。三、聚苯胺的“绿色”合成 以硫酸铁为氧化剂，用化学法合成了聚苯胺。在不同浓度的硫酸溶液中，苯胺的现场可见光谱表明，720 nm处的吸收峰首先形成，它的吸收度随反应时间而增加;然后520nm的吸收峰慢慢形成。吸收峰在720 nm的聚苯胺在水溶液中具有低的溶解度，它的溶解度与苯胺聚合时所用酸的浓度有关。然而，吸收峰在520nm的聚苯胺能完全溶于水中。具有深色的聚苯胺溶液造成环境污染。聚苯胺的红外光谱和循环伏安图受苯胺电化学聚合时使用的硫酸浓度的影响。“绿色”合成聚苯胺的最佳条件是:溶液组成为0.2 mol.d征3苯胺、0.1 moldm“硫酸铁和0.2moldm一，硫酸，温度控制在巧℃以下。更多还原

【Abstract】 The electrochemical synthesis and properties of polyphenol and poly(azure A) and "green" synthesis of polyaniline were mainly studied in this graduation thesis.1. The electrochemical preparation of polyphenol with conductibilityPolyphenol film deposited on platinum foil can continuously grow with time during the electrolysis of a phenol solution consisting of 0.1 mol-dm-3 phenol, 3 mol.dm-3 NaOH and 0.5 mol.dm-3 Na2SO4 which has been proved by the methods of sweep potential, constant potential and constant current, and visible spectra during the electrolysis of phenol. A polyphenol film with thickness of 0.11 mm was obtained by the electrolysis of phenol at a constant potential of 0.70 V (versus Ag/AgCl with saturated KC1 solution). Polyphenol film is an inactive and stable in 2 mol.dm-3 H2SO4 solution, neutral solution and 3 moldm"3 NaOH solution and at the potential range between -0.95 and 1.35 V. The usable potential range is dependent on the pH value. Polyphenol has an ESR signal with a g factor of 2.0049. The conductivity of polyphenol is 1.2×104 S .cm-1. In the solution of polyphenol dissolved in DMSO, the mobility of polyphenol anions is 8 × 10-9 mV.V-1 at 20℃. The FTIR spectrum of polyphenol is presented in this chapter.2. The electrochemical polymerization of azure A and the properties of poly(azure A)The electrochemical polymerization of azure A has been carried out using repeatedpotential cycling. The scan potential is set between -0.2 and 1.3 V (versus Ag/AgCl with saturated KC1 solution). The electrolytic solution consisted of 5 mmol-dm"3 azure A and 0.5 mol.dm-3 Na2SO4 with pH 6.0. The temperature for polymerization was controlled at 50癈. An anodic peak and a cathodic peak appear at 0.38 and 0.23 V, respectively, on the cyclic voltammogram of poly(azure A) in 0.5 moldm-3 Na2SO4 solution of pH 1.0. Their peak potentials shift towards the negative direction as pH value increases from 1.0 to 4.0. Poly(azure A) has a good electrochemical activity and stability in the aqueous solution at the above pH range. The UV-Visible spectrum and FTIR spectrum of poly(azure A) are different from those of azure A. The FTIR spectrum of poly(azure A) indicates that no anions were doped into the oxidation form ofpoly(azure A).3. "Green" synthesis of poly anilinePolyaniline was synthesized chemically with ferric sulfate as oxidant. The in situ visible spectra of the polymerization of aniline in different concentrations of sulfuric acid show that a peak at 720 nm first formed and its absorbance increases with reaction time, and then another peak at 520 nm gradually formed. Polyaniline with the peak at 720 nm has a small solubility in water, depending on the concentration of sulfuric acid used for the polymerization of aniline. However, polyaniline with the peak at 520 nm can completely dissolve in water. Water-soluble polyanilines with intense color will cause environmental pollution. The IR spectra and cyclic voltammograms of polyaniline are affected by the concentrations of sulfuric acid used for the electrochemical polymerization of aniline. The optimum conditions for "green" synthesis of polyaniline are that the solution consisted of 0.2 mol.dm-3 aniline, 0.1 mol.dm-3 ferric sulfate and 0.2 mol.dm-3 sulfuric acid and the reaction temperature was controlled below 15℃.更多还原