Synthesis and electrochemical properties of chitosan-polyphenol composites


REACTIVE & FUNCTIONAL POLYMERS, cilt.154, no.104667, 2020 (SCI İndekslerine Giren Dergi) identifier identifier identifier


A unique series of chitosan-polyphenol composites with superior electrochemical properties, chitosan/poly(2-phenyl hydroquinone) (Ch/PPHQ) and chitosan/poly(2,7-dihydroxy naphthalene) (Ch/PDHN) were synthesized with the phenolic derivates, 2-phenyl hydroquinone (PHQ) and 2,7-dihydroxy naphthalene (DHN) in the presence of chitosan (Ch) biopolymer as a tempate. The synthesized Ch/PPHQ and Ch/PDHN composites were characterized by Fourier transform infrared (FT-IR) spectroscopy, scanning electron microscope (SEM), thermal gravimetric (TG) analysis and their behavior of swelling in the distilled water. Moreover, poly(2-phenyl hydroquinone) (PPHQ) and poly(2,7-dihydroxy naphthalene) (PDHN) were synthesized using PHQ and DHN by oxidative polymerization technique. The synthesized polymers were also characterized by the gel permeation chromatography-light scattering (GPC-LS), ultraviolet-visible (UV-vis) spectroscopy, proton nuclear magnetic resonance (H-1 NMR) spectroscopy, and carbon nuclear magnetic resonance (C-13 NMR) spectroscopy. The M-n and M-w values of the synthesized polymers were obtained in the range of 3.4 and 34.7 kDa. The M-n and M-w values of PPHQ are approximately 2.5-fold higher than the M-n and M-w values of PDHN. Additionally, The M-n and M-w values of PPHQ and PDHN are 1.5-2.5 times higher than the PPHQ* and PDHN* synthesized in Ch matrix. The prepared Ch/PPHQ and Ch/PDHN composites are redox-active materials. The E-HOMO and E-LUMO values of PPHQ, Ch/PPHQ, PDHN, and Ch/PDHN materials were calculated in the range of -4.95 to -5.36 eV and - 3.01 - 3.53 eV by measuring the oxidation (E-ox) and the reduction (E-red) potential values by the cyclic voltammetry (CV). Moreover, the E-g values of PPHQ, Ch/PPHQ, PDHN, and Ch/PDHN were calculated in the range of 1.54-2.14 from the obtained E-HOMO and E-LUMO values. It is seen that Ch/PPHQ and Ch/PDHN composites have lower E-g values than PPHQ and PDHN. According to these results, it can be attributed that Ch/PPHQ and Ch/PDHN composites have preferable electrochemical properties by comparison with the PPHQ and PDHN.