Dielectric properties of chitosan and two ionic derivatives: Effect of counter anions

Salama, Ahmed; Mohamed, F.; Hesemann, Peter

doi:10.1016/j.carbpol.2022.120018

Cited by 7 publications

(4 citation statements)

References 45 publications

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“…This system may be a system with limits in interpretation of the classical equivalent circuit elements. Solvated chitosan itself shows complex dynamics at frequencies below 1 MHz, with several relaxation modes leading to frequency-dependent changes in dielectric properties and hence capacitance. − Since the dynamics change during drying, it is anticipated that they also changes during hydration. Relaxation of a dielectric process can be incorporated into equivalent circuit models by considering explicitly a frequency-dependent capacitance, which was not done here because of the large number of parameters required in the fitting.…”

Section: Resultsmentioning

confidence: 99%

Molybdate and Phosphate Cross-Linked Chitosan Films for Corrosion Protection of Hot-Dip Galvanized Steel

Fernández-Solis,

Keil,

Erbe

2023

ACS Omega

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Environmentally friendly and sustainable methods to protect hot-dip galvanized (HDG) steel from corrosion are extensively studied. Films of the biopolymer polyelectrolyte chitosan were ionically cross-linked in this work with the wellknown corrosion inhibitors phosphate and molybdate. Layers on this basis are presented as components in a protective system and could, e.g., be applied in pretreatments similar to a conversion coating. For the preparation of the chitosan-based films, a procedure involving sol−gel chemistry and wet-wet application was utilized. Homogeneous films of few micrometers thickness were obtained on HDG steel substrates after thermal curing. Properties of chitosan-molybdate and chitosan-phosphate films were compared with purely passive epoxysilane-cross-linked chitosan, and pure chitosan. Delamination behavior of a poly(vinyl butyral) (PVB) weak model top coating studied by scanning Kelvin probe (SKP) showed an almost linear time dependence over >10 h on all systems. Delamination rates were 0.28 mm h −1 (chitosan-molybdate) and 0.19 mm h −1 (chitosan-phosphate), ca. 5% of a non-cross-linked chitosan reference and slightly higher than of the epoxsyilane cross-linked chitosan. Immersion of the treated zinc samples over 40 h in 5% NaCl solution yielded a 5-fold increase of the resistance in the chitosan-molybdate system, as evidenced by electrochemical impedance spectroscopy (EIS). Ion exchange of electrolyte anions with molybdate and phosphate triggers corrosion inhibition, presumably by reaction with the HDG surface as well described in the literature for these inhibitors. Thus, such surface treatments have potential for application, e.g., in temporary corrosion protection.

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Section: Resultsmentioning

confidence: 99%

Molybdate and Phosphate Cross-Linked Chitosan Films for Corrosion Protection of Hot-Dip Galvanized Steel

Fernández-Solis,

Keil,

Erbe

2023

ACS Omega

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“…Moreover, their properties such as specific capacitance, voltage window, energy density, and power density were also discussed. 89 Salama et al 90 investigated the impact of the functionalization of chitosan derivatives on their dielectric properties. In this respect, they synthesized and studied N-guanidinium chitosan acetate (GChAc) and N-guanidinium chitosan chloride (GChCl), and interestingly observed that dielectric loss of the b-process is comparatively smaller in GChAc when compared to Ch, while it is completely eliminated in GChCl, which is probably due to the attached chloride ion that masks any molecular relaxation (Fig.…”

Section: Chitosan and Chitinmentioning

confidence: 99%

mentioning

confidence: 99%

Recent advancements in bio-based dielectric and piezoelectric polymers and their biomedical applications

Yadegari,

Akbarzadeh,

Kargaran

et al. 2024

J. Mater. Chem. B

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“…Sustainable and multifunctional materials derived from renewable resources are increasingly in demand in modern society [ 1 , 2 , 3 , 4 , 5 ]. The development of biobased polymers, and particularly biobased polysaccharides, with antimicrobial activity has been studied in various areas of application, such as medicine, pharmacy, and food [ 6 ].…”

Section: Introductionmentioning

confidence: 99%

Bacterial Cellulose/Cellulose Imidazolium Bio-Hybrid Membranes for In Vitro and Antimicrobial Applications

Salama

Saleh

Cruz‐Maya

et al. 2023

JFB

Self Cite

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In biomedical applications, bacterial cellulose (BC) is widely used because of its cytocompatibility, high mechanical properties, and ultrafine nanofibrillar structure. However, biomedical use of neat BC is often limited due to its lack of antimicrobial properties. In the current article, we proposed a novel technique for preparing cationic BC hydrogel through in situ incorporation of cationic water-soluble cellulose derivative, cellulose bearing imidazolium tosylate function group (Cell-IMD), in the media used for BC preparation. Different concentrations of cationic cellulose derivative (2, 4, and 6%) were embedded into a highly inter-twined BC nanofibrillar network through the in situ biosynthesis until forming cationic cellulose gels. Cationic functionalization was deeply examined by the Fourier transform infrared (FT–IR), NMR spectroscopy, scanning electron microscopy (SEM), energy-dispersive X-ray spectroscopy (EDS), and X-ray diffraction (XRD) methods. In vitro studies with L929 cells confirmed a good cytocompatibility of BC/cationic cellulose derivatives, and a significant increase in cell proliferation after 7 days, in the case of BC/Cell-IMD3 groups. Finally, antimicrobial assessment against Staphylococcus aureus, Streptococcus mutans, and Candida albicans was assessed, recording a good sensitivity in the case of the higher concentration of the cationic cellulose derivative. All the results suggest a promising use of cationic hybrid materials for biomedical and bio-sustainable applications (i.e., food packaging).

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Dielectric properties of chitosan and two ionic derivatives: Effect of counter anions

Cited by 7 publications

References 45 publications

Molybdate and Phosphate Cross-Linked Chitosan Films for Corrosion Protection of Hot-Dip Galvanized Steel

Molybdate and Phosphate Cross-Linked Chitosan Films for Corrosion Protection of Hot-Dip Galvanized Steel

Recent advancements in bio-based dielectric and piezoelectric polymers and their biomedical applications

Bacterial Cellulose/Cellulose Imidazolium Bio-Hybrid Membranes for In Vitro and Antimicrobial Applications

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