Naslov
EPR Study of Polyaniline Synthesized Enzymatically in the Presence of Submicrometer-Sized AOT Vesicles

Autori
Rakvin, Boris ; Carić, Dejana ; Andreis, Mladen ; Junker, Katja ; Walde, Peter

Izvornik
The journal of physical chemistry. B, Condensed matter, materials, surfaces, interfaces & biophysical (1520-6106) 118 (2014), 8; 2205-2213

Vrsta, podvrsta i kategorija rada
Radovi u časopisima, članak, znanstveni

Ključne riječi
polyaniline; EPR; AOT vesicles

Sažetak
EPR spectroscopy was used to examine the magnetic properties of two enzymatically synthesized polyaniline (PANI) samples obtained in the presence of submicrometer-sized vesicles formed from sodium bis(2-ethylhexyl)sulfosuccinate (AOT) as templates. PANI-HRPC-AOT was synthesized with horseradish peroxidase isoenzyme C (HRPC) and hydrogen peroxide (H2O2) as oxidant while PANI- TvL-AOT was prepared with Trametes versicolor laccase (TvL) and dioxygen (O2) as oxidant. A commercial conductive sample of the emeraldine salt form of polyaniline (PANI-ES) was also used for comparison in order to correlate the experimental data obtained for PANI-HRPC-AOT and PANI-TvL-AOT with the properties of the well- characterized PANI-ES. It was shown that a model based on the concept of correlated polaronic bands could be applied for the interpretation of the EPR spectra of all three examined samples, although PANI-HRPC-AOT and PANI-TvL-AOT were significantly less conductive than PANI-ES. The magnetic properties of the PANI samples could be related to their conductivities, whereby a low conductivity was ascribed to decreased interchain spin interactions which were detectable from a splitting of the triplet spectrum at low temperatures (5–10 K). The obtained effective distance between the polyaniline chains is larger for enzymatically synthesized PANI than for PANI- ES, most likely mainly due to the presence of AOT which could not be removed completely during the work-up. AOT influences the chain conformation and the average chain–chain distance.

Izvorni jezik
Engleski

Znanstvena područja
Fizika, Kemija

POVEZANOST RADA