A multifrequency EPR study of poly(PADPA) synthesized with Trametes versicolor laccase from the aniline dimer p-aminodiphenylamine (PADPA) in the presence of anionic vesicles

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• 作者：Dejana Cari膰^a ; Boris Rakvin^a ; ^{rakvin@irb.hr" class="auth_mail" title="E-mail the corresponding author} ; Marina Kveder^a ; Katja Junker^b ; Peter Walde^b ; Edward Reijerse^c
• 关键词：Conducting polymer ; Polyaniline ; N-phenyl-1 ; 4-phenylenediamine ; EPR ; Templates ; Vesicles
• 刊名：Current Applied Physics
• 出版年：2015
• 出版时间：November 2015
• 年：2015
• 卷：15
• 期：11
• 页码：1516-1520
• 全文大小：442 K

文摘

Poly(PADPA) synthesized with the enzyme Trametes versicolor laccase (TvL) at pH = 3.5 in aqueous solution from the aniline dimer p-aminodiphenylamine (PADPA) was studied by EPR spectrometry at X-band and W-band frequencies. For the synthesis of poly(PADPA), vesicles formed from AOT (sodium bis-(2-ethylhexyl)sulfosuccinate) were used as structure-directing templates, and TvL/O₂ as catalyst and oxidant. The isolated product is abbreviated as “poly(PADPA)-TvL-AOT” to distinguish it from poly(PADPA) obtained by other means. The EPR spectrum of poly(PADPA)-TvL-AOT recorded at room temperature is complex. It can be decomposed into two separate Dyson–type spectral components. Furthermore, the spectra measured at high frequency exhibit a line broadening behavior in comparison to the spectra recorded at low frequency where there is no line broadening. This behavior was used to estimate the effective inter-chain spin exchange interaction for each monitored spectral component. The obtained effective distances between the polymer (or oligomer) chains in both identified components of poly(PADPA)-TvL-AOT can be explained by considering slightly different interactions between the chains and the AOT molecules present in the sample. Additionally, due to different average g tensor values, g_av, of these components, it seems that each spectral component originates from one of two different molecular subunits (or local structural motifs) within the polymer (or oligomer) chains.