磁场对微乳液法合成聚苯胺结构及其电化学行为的影响

在不同磁场强度下,采用微乳液聚合法合成导电聚苯胺(PANI),以碳纸负载PANI为工作电极,通过循环伏安测试方法,探讨了磁场、氧化剂浓度和聚合时间对微乳液聚合法合成PANI电化学性能的影响;并通过X射线衍射(XRD)、四探针电导率测试和傅立叶红外光谱(FTIR)对产物结构和性能的表征分析,印证了循环伏安分析结果的可靠性.实验结果表明,与无磁条件下制备的PANI相比,磁场条件下制备的PANI具有较高的导电性和规整度;FTIR谱图分析表明,由于磁场的取向作用使分子间相互作用力降低,分子链离域程度增大,使磁场条件下合成PANI的主要特征峰有向低频方向移动的趋势,但分子的基本结构单元没有发生变化.研究结果显示,利用负载PANI的碳纸为工作电极,能够对微乳液法合成PANI的电化学行为进行有效的实时表征.

EFFECTS OF MAGNETIC FIELD ON ELECTROCHEMICAL BEHAVIOR AND STRUCTURE OF POLYANILINE SYNTHESISED BY MICROEMULSION POLYMERIZATION

The conductive polyaniline (PANI) was synthesized by microemulsion polymerization in the presence of magnetic field.The effects of the magnetic field and preparation conditions such as the oxidant concentration and the polymerization time on the electrochemical properties of PANI were discussed by cyclic voltammetry (CV) using the carbon paper loaded with PANI as working electrode,and the reliability of CV characterization result was proved by the analysis of the FTIR spectra (FTIR),X-ray diffraction (XRD) and four-probe conductivity measurements.The experimental results showed that compared with the PANI synthesized in the absence of a magnetic field,the PANI synthesized in the presence of magnetic field exhibited significant improvement in the crystalline degree and the conductivity properties.FTIR results indicated that the interaction force between molecules reduced,the delocalization of molecular chain increased,and the main characteristic peaks of the PANI prepared in the presence of magnetic field had the trend of moving to low-frequency due to the orientation effect of magnetic field,but the influence of magnetization on the basic structural units of PANI was not observed.The results indicate that electrochemical behavior of the PANI synthesized by microemulsion polymerization can be real-time characterized efficiently by using the carbon paper loaded with PANI as working electrode.