Synthesis and Characterization of Bacterial Cellulose-Polyaniline Composite with Variation of Dopant Concentration

Polyaniline is a type of conductive polymer. Bacterial cellulose has high mechanical properties, so it can be made into polyaniline base composite materials. A stable form of polyaniline oxidation at room temperature is emeraldine base. The emeraldine base has a conductivity value of 10-6 S/cm. Dopants can change the shape of emeraldine base to emeraldine salt by protonation process. Emeraldine salt is a conductive form of polyaniline. The conductivity value of emeraldine salt is 0,03-0,07 S/cm. The addition of dopan in synthesis of polymer was carried out to determine its effect on the conductivity value. The disadvantage of polyaniline is that its mechanical properties are weak and easily brittle. Modifications are needed to improve the mechanical properties of polyaniline, one of which is the manufacture of composite. Bacterial celluloce has high mechanical properties so it can be made into polyaniline base composite materials. Synthesis of bacterial cellulose-polyaniline composites by in situ chemical polymerization methods. Syntehsis is started with BC membrane was dipped into aniline solution for about 2h with stirring at room temperature. The BC was immersed into ammonium peroxydisulfate solution for about 30m with stirring. The bacterial cellulose-polyaniline compositions obtained are black color which is characteristic of the emeraldine salt. The highest conductivity value of composite was obtained from the addition of 3,5M HCl dopant which was 4,70x10-4 S/cm. FTIR analysis of composite obtained peak of the characteristic polyanilin was conductive at 1565,92 cm-1 as C=C quinoid ring and 1442,95 cm-1 as C=C benzoid ring.

Application of an enzymatic cascade reaction for the synthesis of the emeraldine salt form of polyaniline

The synthesis of the emeraldine salt form of polyaniline (PANI-ES) from aniline with Aspergillus sp. glucose oxidase (GOD), d-glucose, dissolved O2, and horseradish peroxidase isoenzyme C (HRPC) in the presence of large unilamellar vesicles of AOT (sodium bis-(2-ethylhexyl)sulfosuccinate) as templates at pH = 4.3 and T ~ 25 °C was investigated in a systematic way. In this cascade reaction mixture, the oxidation of aniline is catalyzed by HRPC with H2O2 that is formed in situ as byproduct of the GOD-catalyzed oxidation of d-glucose with O2. Under the elaborated experimental conditions which we considered ideal, the formation of PANI-ES products is evident, as judged by UV/Vis/NIR and EPR measurements. Comparison was made with a reference reaction, which was run under similar conditions with added H2O2 instead of GOD and d-glucose. Although the reference reaction was found to be superior, with the cascade reaction, PANI-ES products can still be obtained with high aniline conversion (> 90%) within 24 h as stable dark green PANI-ES/AOT vesicle dispersion. Our results show that the in situ formation of H2O2 does not prevent the inactivation of HRPC known to occur in the reference reaction. Moreover, the GOD used in the cascade reaction is inactivated as well by polymerization intermediates.

Azathioprine Electrochemical Adsorption onto the Reduced Graphene Oxide Sheets in Absence and in the Presence of Polyaniline

The azathioprine (AZA) electrochemical adsorption onto the screen-printed carbon electrodes (SPCE) modified with the reduced graphene oxide (RGO) sheets in the absence and in the presence of polyaniline–emeraldine salt (PANI-ES) is reported in this work. Using cyclic voltammetry (CV), in the case of the SPCE modified with the RGO sheets non-functionalized and functionalized with PANI-ES, respectively, an irreversible process at the electrode/electrolyte interface is highlighted to take place. In the case of the SPCE modified with the non-functionalized RGO sheets (SPCERGO), the oxidation-reduction processes induce an up-shift of the AZA Raman lines from 856 and 1011 cm-1 to 863 and 1020 cm-1, respectively. These variations indicate an AZA adsorption onto the surface of the SPCE modified with the RGO sheets that takes place throught the imidazole and pyrimidine cycles of mercaptopurine, when the generation of the π–π* bonds between the mercaptopurine structure and hexagonal carbon cycles of RGO occurs. The electrochemical functionalization of the RGO sheets with PANI-ES is proved by the appearance of the Raman lines at 1165, 1332-1371, 1496 and 1585 and 1616 cm-1. The oxidation-reduction processes induced at the interface of the SPCE modified with PANI-ES functionalized RGO sheets and the electrolyte consisting into a phosphate buffer (PB) and AZA lead to the generation of new positive charges onto the PANI macromolecular chain and the adsorption of the drug on the working electrode surface that takes place via the π–π* bonds established between the benzene/quinoide rings of PANI and the imidazole/ purine cycles of AZA. These results indicate that the SPCE modified with the PANI-ES functionalized RGO sheets shows potential applications in the field of sensors for AZA detection.

Significant Role of Thorny Surface Morphology of Polyaniline on Adsorption of Triiodide Ions towards Counter Electrode in Dye-Sensitized Solar Cells

This paper investigates polyaniline (PANI) adsorption behavior towards triiodide ion (I3-) solution in acetonitrile. Two different types of PANI, namely PANI emeraldine salt (PANI ES) and nanostructured PANI ES (NPES)...

Para-substituted sulfonic acid-doped protonated emeraldine salt nanobuds: a potent neural interface targeting PC12 cell interactions and promotes neuronal cell differentiation

Surface functionalized protonated emeraldine salt (PES) synthesized at 0.18 V provide robust electrically conductive system with low surface resistivity (81.18 mΩ). The PES show ability of cell-type specific microenvironment supporting PC12 cells for neural differentiation.

Effect of Face-to-Face and Side-to-Side Interchain Interactions on the Electron Transport in Emeraldine Salt Polyaniline

Polyaniline (PANI) is a conductive polymer that has been studied intensively due to its high conductivity, ease of synthesis, fascinating doping mechanism, and a broad spectrum of applications. Polyaniline doped...