Antibacterial sugar palm starch biopolymer composite films were developed and derived from renewable sources and inorganic silver nanoparticles (AgNPs) as main ingredients for antibacterial coatings. ...The composite films were produced by solution casting method and the mechanical and physicochemical properties were determined by tensile test, Fourier Transform Infrared (FTIR) analysis, thermal gravimetric analysis (TGA), antibacterial screening test and field emission scanning electron microscopy (FESEM) images. It was found that mechanical and antibacterial properties of biocomposite films were improved after the addition of AgNPs compared with the film without active metals. The weakness of neat biocomposite films was improved by incorporating inorganic AgNPs as a nanofiller in the films' matrix to avoid bacterial growth. The results showed that the tensile strength ranged between 8 kPa and 408 kPa and the elasticity modulus was between 5.72 kPa and 9.86 kPa. The addition of AgNPs in FTIR analysis decreased the transmittance value, caused small changes in the chemical structure, caused small differences in the intensity peaks, and produced longer wavelengths. These active films increased the degradation weight and decomposition temperature due to the more heat-stable AgNPs. Meanwhile, the average inhibited areas measured were between 7.66 and 7.83 mm (
), 7.5 and 8.0 mm (
), and 0.1 and 0.5 mm for
. From the microscopic analysis, it was observed that the average size of all microbes for 1 wt% and 4 wt% AgNPs ranged from 0.57 to 2.90 mm. Overall, 3 wt% AgNP nanofiller was found to be the best composition that fulfilled all the mechanical properties and had better antimicrobial properties. Thus, the development of an organic-inorganic hybrid of antibacterial biopolymer composite films is suitable for antibacterial coatings.
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IZUM, KILJ, NUK, PILJ, PNG, SAZU, UL, UM, UPUK
•PEO/CNCs composites were prepared by solution casting technique.•The composites were characterized by SEM, FTIR, XRD, DSC, TGA, tensile testing.•Morphology, crystalline structure, and reinforcing ...effect have been studied.•Some composites properties are extreme at a certain PEO/CNCs ratio.
Composite films of polyethylene oxide/cellulose nanocrystals (PEO/CNCs) comprising up to 75wt.% CNCs were obtained via solution casting. For the first time, investigations of the PEO/CNCs composite films over a wide composition range were carried out. Morphology, crystalline structure, thermal stability and the resulting reinforcing effect on the PEO matrix were studied. Polarizing optical microscopy (POM), scanning electron microscopy (SEM), X-ray diffraction (XRD), differential scanning calorimetry (DSC), thermogravimetric (TG) analysis, Fourier transform infrared spectroscopy (FTIR), and tensile testing were used to examine the properties of the composites. The revealed extreme dependences of the composite properties refer to the CNCs content of 15–35wt.%. This composition range is characterized by destruction of PEO spherulites and appearance of a pronounced PEO fibrillar structure.
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GEOZS, IJS, IMTLJ, KILJ, KISLJ, NLZOH, NUK, OILJ, PNG, SAZU, SBCE, SBJE, UL, UM, UPCLJ, UPUK, ZRSKP
•An environmentally friendly and electrically conductive PLA/PANI/NCC nanocomposite film was developed.•The thermal stability of the PLA/PANI composite films was improved with PANI ...incorporation.•Increased NCC loading improved the tensile strength and tensile modulus of PLA/PANI/NCC nanocomposite films.•NCC loading led to decreased viscosity and viscoelasticity of PLA/PANI/NCC nanocomposite suspensions.
Polylactic acid (PLA) serves as an ideal matrix for preparing electrically conductive materials for electrode, electromagnetic shielding and functional biological material application. Here, an environmentally friendly PLA/polyaniline (PANI)/nanocrystalline cellulose (NCC) nanocomposite film was prepared. Effects of NCC loadings on the rheological behavior of PLA/PANI/NCC suspensions and the microscopic, thermal, mechanical and conductive properties of nanocomposite films were investigated. Results revealed that PLA was wrapped with PANI particles and NCC was uniformly distributed in the obtained nanocomposite films. The PLA/PANI/NCC films exhibited an electrical conductivity of up to 2.16 S∙m−1 with 1% NCC dosage. Besides, the viscosity and viscoelasticity of the PLA/PANI/NCC suspensions were decreased and the dispersion stability of the suspensions was improved with the incorporation of NCC. Furthermore, the mechanical strength of PLA/PANI/NCC nanocomposite films was significantly improved with the reinforcement effect of NCC. In presence of 4% NCC loading, the tensile strength (TS) and tensile modulus (TM) of PLA/PANI/NCC films had an increase of 38.1% and 89.1%, respectively, while the elongation at break (Eb) exhibited a decrease of 27.3%, as compared to that of PLA/PANI films. These results demonstrated that the as-prepared PLA/PANI/NCC nanocomposite film may have the potential to be used as a bio-based electrically conductive material.
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GEOZS, IJS, IMTLJ, KILJ, KISLJ, NLZOH, NUK, OILJ, PNG, SAZU, SBCE, SBJE, UILJ, UL, UM, UPCLJ, UPUK, ZAGLJ, ZRSKP
•Olive fiber as alternative biomaterial for nanocrystalline cellulose extraction.•Isolation of individual nanoparticles with well dispersed behaviour.•Enhanced cellulose compartment within ...nanocrystals feature.•Highly strong and rigid structure of produced nanocrystalline cellulose.•Improved thermal stability with different acid hydrolysis reaction times treatment.
Olive fiber is a sustainable material as well as alternative biomass for extraction of nanocrystalline cellulose (NCC), which has been widely applied in various industries. In the present study, ONC-I, ONC-II, and ONC-III were extracted from olive stem fiber at different hydrolysis reaction times of 30 min, 45 min, and 60 min, respectively. The nanoparticle size was found gradually reducing from ONC-I (11.35 nm width, 168.28 nm length) to ONC-III (6.92 nm width, 124.16 nm length) due to the disintegration of cellulose fibrils. ONC-II and ONC-III possessed highly pure cellulose compartments and enhanced crystals structure. This study also showed that rigidity increased from ONC-I to ONC-II. ONC-III showed the highest crystallinity of 83.1 %, endowing it as a potentially reliable load-bearing agent. Moreover, ONC-III exhibited highest stable heat resistance among the chemically-isolated nanocellulose. We concluded that olive NCC could be promising materials for a variety of industrial applications in various fields.
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GEOZS, IJS, IMTLJ, KILJ, KISLJ, NLZOH, NUK, OILJ, PNG, SAZU, SBCE, SBJE, UILJ, UL, UM, UPCLJ, UPUK, ZAGLJ, ZRSKP
Nanocrystalline cellulose (NCC) was successfully obtained from two Arctic brown algae species, Laminaria digitata and Saccharina latissima. The production process involved a sequential extraction of ...non-cellulosic compounds, an environmentally friendly bleaching process with hydrogen peroxide, and subsequent acidic hydrolysis, resulting in the formation of nanosized rod-like particles. Comprehensive assessments were conducted to evaluate the influence of hydrolysis conditions, specifically using hydrochloric and sulfuric acids, on the key characteristics of the nanocellulose. The resulting NCC was characterized using various techniques including Fourier-transform infrared spectroscopy (FTIR), X-ray diffraction (XRD), thermogravimetric analysis (TGA, DTG), scanning electron microscopy (SEM), laser diffraction, and low-temperature nitrogen sorption. The obtained algal NCC demonstrated a yield of 76–91%, a degree of polymerization of 150–230 units, and a crystallinity index of 69–80%. The choice of acid during the production significantly influenced the thermal stability, particle size distribution, and porous properties of the samples. Remarkably, the algal NCC, acquired in the form of stable gel-like suspensions, exhibited robust stability during extended storage. These materials showcase promising potential for applications in biomedicine, serving as versatile components for hydro/aerogels, matrices, and fillers in the development of advanced medical dressings.
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GEOZS, IJS, IMTLJ, KILJ, KISLJ, NLZOH, NUK, OILJ, PNG, SAZU, SBCE, SBJE, UILJ, UL, UM, UPCLJ, UPUK, ZAGLJ, ZRSKP
•A novel multifunctional aerogel with micron-scale porous structure was fabricated.•Aerogel3-Cl showed high oil-water separation efficiency.•The addition of quaternarized N-halamine siloxane monomer ...(0.5 wt%) endowed aerogel great antibacterial property.•Aerogel3-Cl had excellent recyclability even used fifty cycles.
The aim of this study was to develop novel aerogels based on nanocrystalline cellulose (NCC), and chitosan (CS) for oily wastewater treatment. The quaternarized N-halamine siloxane monomer (QHS) was successfully synthesized and hydrolyzed to form quaternarized N-halamine siloxane polymer (PQHS) in the mixture of NCC and CS solution to improve the antibacterial properties of aerogels. The strong hydrophilicity of natural polymers NCC and CS and the microporous structure of aerogel endow the underwater oleophobic property. The applications of the aerogels as filter materials for oil/water separation are studied, and showed high separation efficiency of different types of oil/water mixtures. The presence of N-halamine structures in PQHS makes the aerogels effectively kill bacteria in oily sewage and inhibit the growth of bacteria on the surface of the materials. The properties of exceptional reusability, oil/water separation efficiency, and antibacterial efficacies render the aerogels as promising materials with potential applications in oily wastewater treatment.
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GEOZS, IJS, IMTLJ, KILJ, KISLJ, NLZOH, NUK, OILJ, PNG, SAZU, SBCE, SBJE, UL, UM, UPCLJ, UPUK, ZRSKP
Scaffolds of tissue engineering for particular sites, for example, nerve, cardiac, and bone tissues, require a comprehensive design of 3D biomaterials that covers all aspects of physical structures ...and chemical composition, needed for desired cell regeneration. Injectable and in situ forming hydrogel scaffolds, possessing highly hydrated and interconnected structures, have demonstrated several advantages for use in regenerative medicine. In this study, we have developed a new design of injectable hydrogels based on collagen, aldehyde modified-nanocrystalline cellulose, and chitosan loaded with gold nanoparticles (Collagen/ADH-CNCs/CS-Au). The results of experiments exposed that the various molar ratios of Collagen/CNCs and the presence of CS-Au content have a significant effect on the microscopic morphology, equilibrium swelling, in vitro degradation, and mechanical properties of the hydrogels. The cytotoxicity analysis was performed for the NIH 3T3 cell line, which displays the effectiveness and non-toxicity of the developed hydrogels towards the destruction of the cells. The achieved results suggested that the prepared hydrogel network has great potential as a new biomaterial for tissue engineering applications.
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GEOZS, IJS, IMTLJ, KILJ, KISLJ, NLZOH, NUK, OILJ, PNG, SAZU, SBCE, SBJE, UILJ, UL, UM, UPCLJ, UPUK, ZAGLJ, ZRSKP
The bio-nanocomposites of cationic starch (CS)/montmorillonite (MMT)/nanocrystalline cellulose (NCC) were produced by solution casting method. The effects of NCC and MMT nanoparticles on optical, ...barrier and mechanical properties of CS films were investigated. X-ray diffraction results confirmed the partly intercalated and partly exfoliated structure of CS/MMT/NCC films. The FTIR test showed the forming of new hydrogen bonds between the CS hydroxyl groups and nanoparticles. FESEM analysis proved that the dispersion of NCC and MMT in the CS matrix is homogenous. The optical clarity of CS based films was almost unaffected in presence of MMT and NCC. The ternary nanocomposites with 5 wt% NCC and MMT showed the best improvements in the properties. The tensile strength and the tensile modulus of nanocomposites increased up to 61% and 73% respectively, compared to the pure CS film. The nanocomposites demonstrated highest disintegrability rate and good reduction in water vapor and oxygen permeability with addition of NCC.
•NCC was successfully incorporated in the CS matrix with MMT.•NCC improved the water vapor and oxygen barrier properties of the CS nanocomposites.•Incorporation of NCC and MMT didn't reduce the transparency of the nanocomposites.•Disintegrability of nanocomposites was affected by addition of NCC and MMT.•5 wt% NCC is the most effective content to improve the properties of the CS films.
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GEOZS, IJS, IMTLJ, KILJ, KISLJ, NLZOH, NUK, OILJ, PNG, SAZU, SBCE, SBJE, UILJ, UL, UM, UPCLJ, UPUK, ZAGLJ, ZRSKP
Anatase TiO2 nanocrystals have been organized into high‐surface‐area (150–230 m2 g−1) mesoporous films with long‐range chiral nematic ordering. The chiral structure of the anatase films causes them ...to selectively reflect circularly polarized light and appear iridescent. These materials show replication of structural features found in the silica template on nanometer to millimeter length scales.
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BFBNIB, FZAB, GIS, IJS, KILJ, NLZOH, NUK, OILJ, SBCE, SBMB, UL, UM, UPUK
Adsorption is a common technique for the treatment of dye-contaminated wastewater. Achieving a high dye removal capacity is a common challenge with sustainable, low-cost adsorbents. Recently, a class ...of easily functionalized, biorenewable cellulose nanoparticles called hairy nanocellulose has been developed. Electrosterically stabilized nanocrystalline cellulose (ENCC), which can be synthesized from wood pulp through a two-step oxidation by periodate and chlorite, is a form of hairy nanocellulose with a high negative charge density, and thus has the potential for a high adsorption capacity. In this work, the adsorption of methylene blue, a cationic dye, by ENCC was shown to occur up to charge stoichiometry (1400 mg dye/g adsorbent), at which point aggregation of ENCC–dye complexes is observed. A model is developed to show that the adsorption can be described by an ion-exchange mechanism and is influenced by the presence of other ions. Equilibrium dye removal is reduced at both high ionic strengths and low pH. To facilitate handling, composite hydrogel beads of sodium alginate and ENCC (ALG–ENCC beads) are developed, and their methylene blue removal capacity is shown to maintain a high removal capacity (1250 mg/g). ALG–ENCC beads provide a facile way to employ these nanoparticles on a larger scale, providing a potential means for the removal of dyes and other contaminants at larger wastewater volumes.
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IJS, KILJ, NUK, PNG, UL, UM
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