利用核磁共振技术原位追踪了在酸性条件下以NaVO3为氧化剂氧化苯胺制备聚苯胺纳米棒的形成过程。通过分析反应中各主要物种共振吸收峰的信号演变规律及彼此在时域上的关联性，得出聚苯胺纳米棒的成核过程经历了两个主要阶段：诱导期和晶种聚集期。相较其它一维纳米材料(纳米纤维和纳米管)，聚苯胺纳米棒的成核过程具有如下特点：①非常长的诱导期；②由单体组成的胶束在成核前后结构保持不变；③反应初期只生成具有吩嗪结构的寡聚物。较长的诱导期有助于反应前苯胺单体排列成棒状胶束，吩嗪寡聚物中高度共轭的芳环使之容易在反应前期与胶束中的苯胺相互作用，并且最终在棒状胶束的诱导下紧密排列成一维纳米棒。%A study on the nucleation mechanism of polyaniline nanorods ( PANI NRs) via an oxidative polymerization of aniline by NaVO3 under acidic condition was explored by in situ 1 H NMR spectroscopy. Based on the signal evolution of the oligomers and the monomer, the formation of PANI NRs was derived to be experienced through two stages: an induction period and a growth-up one. In compared with the other 1 D nanostructured PANIs such as nanofibers and nanotubes, this process was featured by the following characters: an extremely long induction period, no significant structural transition for anilinium composed micelles, the formation of only phenazine-like oligomers. The long induction period provided good opportunity for all reagents to be arranged regularly. On the other hand, the fused ring-structure of phenazines favored the coagulation with the monomer, and eventually leaded to the formation of PANI NRs.
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