Janosević Aleksandra, Cirić-Marjanović Gordana, Marjanović Budimir, Holler Petr, Trchová Miroslava, Stejskal Jaroslav
Faculty of Physical Chemistry, University of Belgrade, Studentski Trg 12-16, 11001 Belgrade, Serbia.
Nanotechnology. 2008 Apr 2;19(13):135606. doi: 10.1088/0957-4484/19/13/135606. Epub 2008 Feb 26.
Conducting polyaniline 5-sulfosalicylate nanotubes and nanorods were synthesized by the template-free oxidative polymerization of aniline in aqueous solution of 5-sulfosalicylic acid, using ammonium peroxydisulfate as an oxidant. The effect of the molar ratio of 5-sulfosalicylic acid to aniline on the molecular structure, molecular weight distribution, morphology, and conductivity of polyaniline 5-sulfosalicylate was investigated. The nanotubes, which have a typical outer diameter of 100-250 nm, with an inner diameter of 10-60 nm, and a length extending from 0.4 to 1.5 microm, and the nanorods, with a diameter of 80-110 nm and a length of 0.5-0.7 microm, were observed by scanning and transmission electron microscopies. The presence of branched structures and phenazine units besides the ordinary polyaniline structural features was revealed by infrared and Raman spectroscopies. The stacking of low-molecular-weight substituted phenazines appears to play a major role in the formation of polyaniline nanorods. The precipitation-dissolution of oligoaniline templates as a key element in the formation of polyaniline nanotubes is proposed to explain the crucial influence of the initial pH of the reaction mixture and its decrease during the course of polymerization.
通过在5-磺基水杨酸水溶液中以过硫酸铵为氧化剂，对苯胺进行无模板氧化聚合，合成了聚苯胺5-磺基水杨酸盐纳米管和纳米棒。研究了5-磺基水杨酸与苯胺的摩尔比对聚苯胺5-磺基水杨酸盐的分子结构、分子量分布、形态和电导率的影响。通过扫描电子显微镜和透射电子显微镜观察到，纳米管的典型外径为100-250nm，内径为10-60nm，长度为0.4至1.5微米，纳米棒的直径为80-110nm，长度为0.5至0.7微米。红外光谱和拉曼光谱显示，除了普通的聚苯胺结构特征外，还存在分支结构和吩嗪单元。低分子量取代吩嗪的堆积似乎在聚苯胺纳米棒的形成中起主要作用。提出低聚苯胺模板的沉淀-溶解是聚苯胺纳米管形成的关键因素，以解释反应混合物初始pH值及其在聚合过程中的降低的关键影响。
