层层自组装原位聚合聚苯胺复合膜成膜机理研究

从苯胺单体出发, 通过原位聚合、现场掺杂以及基于静电力的层层自组装制备了聚苯胺复合膜. 通过苯胺活性溶液的温度及颜色变化跟踪聚合反应进程, 同时考察不同聚合反应阶段所得聚苯胺复合膜的紫外-可见吸收, 并进一步探讨聚苯胺复合膜的成膜机理. 研究表明, 成膜机制是由聚合反应初始阶段的苯胺阳离子或苯胺阳离子自由基通过静电作用快速吸附到负电性的基片表面, 形成均匀的聚合中心, 链增长生成聚苯胺; 该聚苯胺在酸性条件下经现场掺杂显电正性, 可吸附电负性的聚苯乙烯磺酸钠(PSS), 以此循环层层组装得到多层聚苯胺复合膜.

Mechanism Studies of Layer-by-Layer Self-assembled in situ Polymerized Polyaniline Composite Film Formation

Polyaniline (PANI) composite films were prepared from aniline monomers by in situ polymeri- zation,acid-doping and layer-by-layer self-assembly through the electrostatic force.The progress of polym- erization was monitored by temperature and color changes of chemically active aniline aqueous solution. The UV-vis spectra of the PANI composite films prepared at various polymerization stages were detected, from which the preliminary mechanism of the film formation was studied.It was proposed that the self-assembly of polyaniline occurred through the quick absorption of aniline monomer cations or aniline monomer cation radicals on the glass surfaces by electrostatic attractions to form homogeneous polymeriza- tion centers,and then the chain grows to polyaniline.The polyaniline which was doped under acidic condition,carried positive charge to absorb anionic sodium polystyrene sulfonate (PSS),and it thus recycled to layer-by-layer self-assembly multilayer polyaniline composite films.