二苯胺与邻氨基酚共聚的原位紫外-可见光谱电化学研究

In Situ UV-Vis Spectroelectrochemical Study on the Copolymerization of Diphenylamine and o-Aminophenol

运用循环伏安法(CV)和原位紫外-可见光谱电化学法研究了二苯胺(DPA)和邻氨基酚(OAP)在4mol/L H2SO4中单独聚合及二者共聚的电化学过程。DPA和OAP单独聚合及二者共聚时不同的电化学行为表明DPA和OAP之间发生了共聚作用。原位紫外-可见光谱研究表明,在DPA与OAP的共聚过程中,DPA与OAP首先被氧化生成阳离子自由基,然后,两者的阳离子自由基与溶液中的DPA和OAP单体或其自由基发生交互反应产生混合二聚物中间体,其吸收峰位于508 nm处。进一步研究发现,DPA和OAP的共聚过程与溶液中各单体的浓度比有关。

The electrochemical copolymerization of diphenylamine （DPA） and o-aminophenol （OAP） was studied by using in situ ultraviolet- visible（ UV -Vis） speetroeleetrochemical and cyclic voham- metric techniques. The different vohammetrie characteristics between the homopolymerization and co- polymerization processes exhibited the occurrence of the copolymerization of DPA and OAP in 4 tool/ L H2SO4. The in situ UV - Vis spectra showed that, during the copolymerization of DPA and OAP, DPA and OAP were firstly oxidized to generate their cation radicals, then a mixed oligomer intermedi- ate was formed by the cross-reaction of the cation radicals of DPA and OAP with the DPA and OAP monomers or their cation radicals in solution, and the absorption peak located at 508 nm was assigned to this intermediate. Further studies showed the difference was existed between the copolymerization of DPA and OAP with different concentration ratios, indicating the dependence of the copolymeriza- tion on the concentrations of DPA and OAP.