掺杂质子酸的类型对聚苯胺结构和电导率的影响

Effect of Protonic Acids Types on the Structures and Conductivity of Polyaniline

采用化学氧化聚合法以苯胺为单体 ,过硫酸铵为氧化剂 ,在不同质子酸的水溶液中合成聚苯胺 ,考察质子酸对聚苯胺电性能影响 ,并通过傅立叶红外吸收光谱 (FTIR)和紫外可见光吸收光谱 (UV vis)研究聚苯胺掺杂前后结构的变化。结果表明 ,经质子酸掺杂后聚苯胺具有导电性是因为其分子链上电荷离域形成了共轭结构 ,且在不同质子酸中生成的聚苯胺氧化程度不同 ;分子链共轭程度与掺杂酸对阴离子大小有关 ,掺杂质子酸对阴离子越大 ,聚苯胺分子链共轭程度越大 。

Polyaniline were synthesized in various protonic acids aqueous solution by chemical oxidization polymerization, using aniline as monomer and ammonium persulfate as oxidant. And its electrical properties were studied as a function of protonic acids. The structural changes of polyaniline were measured by FTIR and UV vis. It is found that the good conductivity of polyaniline is attributed to the dislocating of charge and the forming of conjugation of molecular chain after doped by protonic acid, and the oxidation state of polyaniline is different as synthesizing in different protonic acids; the conjugation is affected by the size of counterion of protonic acid.The larger the counterion of polyaniline, the more conjugate the polyaniline molecular, the more conductivity the polyaniline.