Chitosan-based Composite Materials Research Articles

Recent Advances in Chitosan-Based Composite Materials in Organic Transformations - A Review

Abstract: Chitosan (CS) is a crustacean-derived bio-macromolecular base. Physico-chemical properties of CS resemble cellulose, and the chemical structure constitutes β-(1-4)-linked D-glucosamine and N-acetyl-D-glucosamine units. It has tunable characteristics such as molecular weight, degree of acetylation, and acetyl distribution. It is proven to be a very good support in making catalysts and functional materials. This article comprises the recently published articles using CS-based composites as heterogeneous catalysts in numerous chemical transformations of industrial relevance. In this connection, the CS-based composite materials have been successfully used as heterogeneous catalysts in a wide range of organic transformations including cycloaddition, trimethylsilylation, cyanation, Suzuki-Miyaura, Heck, Beckmann rearrangement, O-carboxymethylation, nitroarenes reduction, nucleophilic acylation (phenyl acetates from acid chlorides), Knoevenagel condensation, biomass valorization, P–O bond formation, imination, dipolar addition, and multicomponent reactions. The CS has also been used to prepare magnetic nanocomposite-based catalysts that showed easy separation and high reusability. This article is highly helpful in designing further chemical transformations where the role of the bio-polymeric base, CS may be critical.

Influence of chitin nanofibrils ultrasonic treatment on structure and properties of chitosan-based composite materials

The influence of ultrasonic treatment parameters of chitin nanofibrils aqueous suspension on structure, strength and deformation properties of chitosan-based composite films and fibers was investigated. Model calculations of ultrasound-induced cavitation parameters in the aqueous suspension of the chitin nanofibrils showed that an increase in the field power up to 630 W led to destruction of the cavity, to an increase in the temperature in the vicinity of cavitation area (up to 507 °C) and, as a consequence, to destruction of chitin glycoside ring (which is confirmed by the IR data). The results of light scattering, IR spectroscopy, and electron microscopy investigations indicated that the optimal duration of ultrasonic treatment of the chitin nanofibrils aqueous solution was 4–10 min (depending on oriented state of the scaffold). Tensile strength of the composites was 130 ± 11 MPa (films), 226 ± 4.8 MPa (fibers); deformation at break was 43 ± 7.5% (films), 10 ± 0.6% (fibers).

Electrophysical properties of chitosan-based composite films filled with single-wall carbon nanotubes

This work focuses on new chitosan-based composite materials. In order to improve chitosan conductivity, single-wall carbon nanotubes (SWCNT) were added as a filler. The structure of the composites was studied using a scanning electron microscope. It is shown that the addition of SWNCT filler leads to chitosan structure ordering. The increase in SWCNT content from 0 wt.% to 3.0 wt.% leads to an increase in composite film conductivity from 10−11 to 10 S/m, with the relative dielectric permittivity change from 5.5 to 26 at 1 kHz. The effect of moisture on the films’ dielectric properties was also studied.

Synthesis of granulated H4Mn5O12/chitosan with improved stability by a novel cross-linking strategy for lithium adsorption from aqueous solutions

Adsorption is one of the most promising methods for lithium recovery from aqueous solutions. Herein, eco-friendly chitosan (CTS) was used to prepare granulated H4Mn5O12 (HMO) ion-sieve for lithium adsorption from aqueous solutions. It was found that the hydroxyl and amino groups in CTS can react with the epoxy group and alkyl chloride in epichlorohydrin (ECH) under acidic and alkaline conditions, respectively. This unique property resulted in the adequate cross-linking of CTS and the uniform distribution of HMO in the CTS matrix by a novel two-step cross-linking strategy with ECH as the cross-linking agent. Especially when the superfine hydrogen-type rather than lithium-type ion-sieve was coated by this method at a mass ratio of CTS/HMO = 1:1, the material exhibited high thermal and chemical stability. The dissolution loss of Mn was no more than 1.15% in 0.25 mol·L−1 HCl even after 24 h continuous stirring, and it still maintained good thermal stability at 433 K. When the material was used for Li+ (25.78 mg·L−1) recovery from geothermal water which is characterized by high temperature, the adsorption capacity reached 11.4 mg·g−1 with a recovery rate of 88.42% at a solid-to-liquid ratio of 4 g·L−1. Because chitosan is widely applied for the preparation of various adsorption materials, the cross-linking strategy developed in this work provides a new idea for the preparation of chitosan-based composite materials with high stability and adsorption properties.

Porosity Pattern of 3D Chitosan/Bioactive Glass Tissue Engineering Scaffolds Prepared for Bone Regeneration

Aim: The study was conducted to investigate the obtained external and internal porosity and the pore-interconnectivity of specific fabricated bioactive composite tissue engineering scaffolds for bone regeneration in dental applications. Materials and Methods: In this study, the bioactive glass [M] was elaborated as a quaternary system to be incorporated into the chitosan [C] scaffold preparation on a magnetic stirrer to provide bioactivity and better strength properties for the attempted composite scaffolds [C/ M] of variable compositions. The homogenous chitosan/bioactive glass mix was poured into tailor-made cylindrical molds [10cm×10cm]; a freeze-dryer program was used for the creation of uniform and interconnected macropores for all prepared chitosan-based scaffolds. The morphology of fabricated chitosan [C] and chitosan-bioactive glass [C/ M] composite scaffolds was studied by a scanning electron microscope [SEM] and a mercury porosimeter. In addition, the in-vitro biodegradation rate of all elaborated scaffolds was reported after immersing the prepared scaffolds in a simulated body fluid [SBF] solution. Furthermore, for every prepared scaffold composition, characterization was performed for phase identification, microstructure, porosity, bioactivity, and mechanical properties using an X-ray diffraction analysis [XRD], an X-ray Fourier transfer infrared spectroscopy [FTIR], a mercury porosimetry, a scanning electron microscopy [SEM] coupled to an energy-dispersive X-ray spectrometry [EDS] and a universal testing machine, respectively. Results: All the prepared porous chitosan-based composite materials showed pore sizes suitable for osteoblasts seeding, with relatively larger pore sizes for the C scaffolds. Conclusion: The smart blending of the prepared bioactive glass [M] with the chitosan matrix offered some advantages, such as the formation of an apatite layer for cell adhesion upon the scaffold surfaces, the reasonable decrease in scaffold pore size, and the relative increase in compressive strength that were enhanced by the incorporation of [M]. Therefore, the morphology, microstructure, and mechanical behavior of the elaborated stress loaded biocomposite tissue engineering scaffolds seem highly dependent on their critical contented bioactive glass.

Advances in Research of Chitosan-based Composites for Implanted Medical Devices

It is well known that chitosan-based composites are widely used in implantable medical devices. The development of chitosan-based composite materials with different types was summarized in this paper, such as inorganic, organic and composite phases. Then, combined with the research focus, the development of 3D printing technology and chitosan-based composites was summarized. It was also pointed out that the existing problems in our research, which need to be solved urgently. At last, the development direction and broad application prospect of chitosan-based composites were prospected. And we look forward to providing reference for relevant research.

Electrophoretic deposition and characterization of chitosan-molybdenum composite coatings

In this paper, the effect of the electric field on the properties of a new chitosan-molybdenum (Chit-Mo) composite coating obtained by electrophoretic deposition (EPD) was investigated. The composite coatings obtained showed different morphologies depending on the conditions used during the deposition process. Chemical composition results and microstructure analysis showed homogeneous distribution of molybdenum in a chitosan matrix. Corrosion test results showed that the Chit-Mo composite coatings can increase corrosion resistance of 1020 steel in NaCl medium (3.5 %). The coatings obtained at 5 V, pH 5.5, and using a low concentration of reagents (suspension 1: chitosan 0.5 g/L and 1 mM sodium molybdate) reached an inhibition efficiency of up to 76.7 %. Therefore, the results obtained in this work prove the achievement of a new class of chitosan-based composite materials with potential application in the protection of metal structures against corrosion.

Characterization of the chitosan-tungsten composite coating obtained by electrophoretic deposition

In this research, a new type of composite coating made of chitosan-tungsten (Chit-W), was obtained by the process of electrophoretic deposition (EPD) and characterized. The deposition parameters (potential and pH) were evaluated. The results of surface morphology (SEM), chemical composition (EDS), crystallography (XRD) and infrared spectroscopy (FT-IR) confirmed the deposition of the composite film consisting of a tungsten impregnated chitosan matrix with different morphology types. Corrosion resistance results obtained by potentiodynamic polarization (PP) and electrochemical impedance spectroscopy (EIS) showed that the coatings can be applied for temporary protection of exposed steel (1020) in NaCl (3.5 %) medium. Therefore, this work proves the deposition of a new class of chitosan-based composite materials with potential applications in different technological sectors.

Assessing the potential of boronic acid/chitosan/bioglass composite materials for tissue engineering applications.

Composite materials aimed at bone tissue engineering need to have suitable bioactivity in order to promote cell proliferation and adhesion. In this article, we study the potential of boronic acids to improve the bioactivity of chitosan-based composite materials. Samples were prepared using boronic acid functionalised chitosan and Bioglass 45S5. These composite materials, prepared by freeze-drying, exhibit 3D interconnected porosity. The materials were fully characterized using scanning electron microscopy (SEM), FT-IR and x-ray diffraction. Their bioactivity was assessed by immersion in simulated body fluid and cell cytotoxicity assays. Composite materials containing boronic acid show no toxicity for Mouse Sertoli (TM4), Human embryonic kidney 293 (Hek293) and Human bone marrow/stroma (HS-5) cells, as opposed to composites containing non-functionalised chitosan.

Could the porous chitosan-based composite materials have a chance to a "NEW LIFE" after Cu(II) ion binding?

Currently, biosorption is considered a leading-edge environmentally-friendly method for the low-cost remediation of wastewaters contaminated with metal ions. However, the safe disposal of metal-loaded biosorbents is still a challenging issue. In this context, our major objective was to explore the possibility of "waste minimization" by reusing the metal-loaded biosorbents in further environmental applications, particularly into the oxidative catalysis of dyes. Thus, the decolourisation efficiency (DE) of Methyl Orange (MO) in aqueous solutions under ambient light using copper-imprinted chitosan-based composites in comparison to non-imprinted ones was investigated in this work. The MO degradation was established first in the absence of any co-catalyst, when a DE value of 95.3% was achieved by the ion-imprinted catalysts within 360 min of reaction, compared to only 67.4% attained by the non-imprinted ones. Under Fenton-like conditions, the apparent degradation rate constant was seventy times higher, the DE increasing within 40 min to about 98.6%, and 70.5% respectively, whereas the content of co-catalyst (H2O2) was significantly lowered compared to other reported studies. The straightforward preparation of copper-loaded composites, along with their excellent stability and high efficiency even after four consecutive reaction runs support our ion-imprinted systems as potential catalysts for dye removal by oxidative decolourisation treatments.

New Chitosan/Iron Oxide Composites: Fabrication and Application for Removal of Sr2+ Radionuclide from Aqueous Solutions.

Here, we discuss the fabrication and problems of application of chitosan-based composite materials for the removal of hazardous metal ions from tap water and wastewater. The chitosan-based composites containing iron oxides for the uptake of Sr2+ ions were fabricated via a co-precipitation method with variation of the iron/chitosan ratio and pH of the medium. The morphology and composition of the fabricated sorbents were characterized using scanning electron microscopy–energy dispersive X-ray spectroscopy (SEM–EDX) and X-ray diffraction (XRD) analysis. We have shown that the suggested fabrication approach allows for a homogeneous distribution of the inorganic phase in the polymer matrix. Investigations of the sorption performance of the composites have shown that they are efficient sorbents for 90Sr radionuclides uptake from tap water. The composite sorbent containing amorphous iron oxide in a chitosan matrix and calcined at 105 °C showed the best sorption characteristics. We have also demonstrated that there is an optimal iron oxide content in the composite: with increasing oxide content, the efficiency of the sorbents decreases due to poor stability in solution, especially in alkaline media. The alternative approach yielding magnetic chitosan-based composites with sufficiently good sorption performance and stability in neutral and weakly alkaline media is suggested.

A structural study of self-assembled chitosan-based sponge materials

Uncontrolled dissolution in solvent media is a key challenge related to the utility of chitosan composite materials. Thermal annealing offers a solution to address this problem. However, conventional characterization methods pose limitations regarding key structural features, especially for carbohydrate materials that possess similar biopolymer components. Herein, self-assembled chitosan-based sponges were prepared with and without annealing to compare their structural and physicochemical properties. The utility of Raman micro-imaging is reported with dye probe etching as an effective and facile method to reveal structural features for chitosan-based composite materials, before and after thermal annealing. We proposed that such composites undergo a structural change from a loosely packed to a more densely packed structure. As well, the multi-functional role of polyethylene oxide in the composites and the potential role of solvent etching was evaluated. The improved stability of the treated composites reveals their potential utility for applications in aqueous media.

Chitosan-Based Composite Materials for Prospective Hemostatic Applications.

Effective hemostasis is vital to reduce the pain and mortality of patients, and the research and development of hemostatic materials are prerequisite for effective hemostasis. Chitosan (CS), with good biodegradability, biocompatibility and non-toxicity, has been widely applied in bio-medicine, the chemical industry, the food industry and cosmetics. The excellent hemostatic properties of CS have been extensively studied. As a result, chitosan-based composite hemostatic materials have been emerging. In this review, the hemostatic mechanism of chitosan is briefly discussed, and then the progress of research on chitosan-based composite hemostatic materials with multiple forms such as films, sponges, hydrogels, particles and fibers are introduced. Finally, future perspectives of chitosan-based composite hemostatic materials are given. The objective of this review is to provide a reference for further research and development of effective hemostatic materials.