Poly Vinyl Alcohol Blend Research Articles

Electrospun Chitosan-Polyvinyl Alcohol Nanofiber Dressings Loaded with Bioactive Ursolic Acid Promoting Diabetic Wound Healing.

The design and development of novel dressing materials are urgently required for the treatment of chronic wounds caused by diabetic ulcers in clinics. In this study, ursolic acid (UA) extracted from Chinese herbal plants was encapsulated into electrospun nanofibers made from a blend of chitosan (CS) and polyvinyl alcohol (PVA) to generate innovative CS-PVA-UA dressings for diabetic wound treatment. The as-prepared CS-PVA-UA nanofiber mats exhibited randomly aligned fiber morphology with the mean fiber diameters in the range of 100–200 nm, possessing great morphological resemblance to the collagen fibrils which exist in the native skin extracellular matrix (ECM). In addition, the CS-PVA-UA nanofiber mats were found to possess good surface hydrophilicity and wettability, and sustained UA release behavior. The in vitro biological tests showed that the high concentration of UA could lead to slight cytotoxicity. It was also found that the CS-PVA-UA nanofiber dressings could significantly reduce the M1 phenotypic transition of macrophages that was even stimulated by lipopolysaccharide (LPS) and could effectively restore the M2 polarization of macrophages to shorten the inflammatory period. Moreover, the appropriate introduction of UA into CS-PVA nanofibers decreased the release levels of TNF-α and IL-6 inflammatory factors, and suppressed oxidative stress responses by reducing the generation of reactive oxygen species (ROS) as well. The results from mouse hepatic hemorrhage displayed that CS-PVA-UA nanofiber dressing possessed excellent hemostatic performance. The in vivo animal experiments displayed that the CS-PVA-UA nanofiber dressing could improve the closure rate, and also promote the revascularization and re-epithelization, as well as the deposition and remodeling of collagen matrix and the regeneration of hair follicles for diabetic wounds. Specifically, the mean contraction rate of diabetic wounds using CS-PVA-UA nanofiber dressing could reach 99.8% after 18 days of treatment. In summary, our present study offers a promising nanofibrous dressing candidate with multiple biological functions, including anti-inflammation, antioxidation, pro-angiogenesis, and hemostasis functions, for the treatment of hard-to-heal diabetic wounds.

Strength Properties and Toughness Indices of Hybrid Polymeric Fibre Reinforced Renewable Oil Palm Shell Concrete

In this study, the strength properties and durability of polymeric fibre-reinforced concrete containing renewable oil palm shell (ROPS) lightweight aggregate were investigated. The effect of individual Polyvinyl Alcohol (PVA) fibre, individual Polypropylene (PP) fibre and hybrid PVA-PP fibre with various percentage of volume fraction, Vf (0, 0.3 and ‘0.25+0.05’%) on the compressive strength and toughness indices of ROPS LWC were examined. The research outcomes show that compressive strength of ROPS lightweight concrete strengthened with individual PVA fibre or PP fibre enhanced with the increase of Vf fibre. From the results, toughness indices increased significantly by 38.3% compared to control mix. Furthermore, the hybrid ‘PVA0.25/PP0.05’ had revealed the optimum results as associated to other mixes. Thus, the outcomes of this paper showed that the blend of both PVA and PP polymeric fibre could potentially be utilized in concrete industry.

Chitosan-based electrospun nanofibers mat for the removal of acidic drugs from influent and effluent

In this study, electrospinning was used to synthesize the nanofibers from a blend of chitosan and polyvinyl alcohol (PVA) to remove acidic drugs from wastewater. Fibers with uniform morphology were obtained at voltage of 20 kV, flow rate of 0.2 mL/h, and collection distance of 10 cm. The chemical and physical properties of the produced nanofibers were investigated utilizing a variety of equipment, including SEM, FTIR, XRD, and TGA-DSC. The nanofibers contain active hydroxyl and amino functional groups with an average diameter of 380 nm, according to the characterization results of FTIR and SEM. From the XRD and TGA-DSC analysis, the nanofibers were found to be amorphous and thermally stable at 200 °C. A thermal treatment to the nanofibers was done to reduce the water solubility of the fibers prior to their application for the adsorption of acidic drugs from water systems. Using the ultra-pure water, maximum removal capacities (qm) were calculated from Langmuir isotherm and were found to be 27.85, 1666.66, 166.6, and 1250 mg/g for acetyl salicylic acid, naproxen, fenoprofen, and diclofenac, respectively.

Chemically bonded tungsten-based polymer composite for X-rays shielding applications

Lead-free metal-polymer composite based X-ray shielding apparel has been of great concern in recent years due to its flexibility, less toxicity, lightweight, etc. The conventional metal-polymer composites based apparels suffers from non-uniform attenuation due to the non-uniform distribution of fillers in the polymer matrix. In this work, efforts were made to address this drawback by developing a chemically bonded metal-polymer composite by incorporating tungsten trioxide (WO3) solution in the blend of polyvinyl alcohol and polyvinyl pyrrolidone. Developed composites were characterized and their X-ray attenuation properties were determined using the X-ray tube voltage of 50–140 kV. The XRD and SEM analyses revealed the formation of the sodium tungstate (Na2WO4.2H2O) phase and its uniform distribution in the polymer matrix, respectively. FT-IR and XPS data showed the formation of a coordinate bond between the W and polymer matrix, which is responsible for the uniform distribution of W-based filler. The polymer composite made with 17 % of WO3 loading is found to be optimum. The 2.35 mm thick sample possesses the attenuation equivalent to 0.25 mm lead at 100 kV, which is recommended by IAEA (International Atomic Energy Agency) to fabricate radiation shielding aprons to attenuate scattered X-rays. The developed composite shows a tensile strength of 4.6 MPa, which is suitable for fabricating wearable radiation shields.

Investigation of polyvinyl alcohol (PVAL) composite gels and the outcome of variation in breast phantom densities on image quality and dose in full-field digital mammography

This study evaluates the possibility of using a blend of polyvinyl alcohol (PVAL) and graphite powder as phantom materials to stimulate an extremely dense breast tissue for mammography based on the Breast Imaging-Reporting and Data System (BIRADS). The linear (μ) and mass attenuation coefficients (μ/ρ), computed tomography (CT) number, and physical and relative electron densities of the fabricated PVAL materials were determined. Mammography images of the fabricated PVAL materials and standard RMI 156 mammography phantoms were acquired using full-field digital mammography (FFDM) system at 28 kVp. The effect of breast density on contrast (Cn), contrast-to-noise ratio (CNR), signal-to-noise ratio (SNR), and mean glandular dose (MGD) were evaluated. The fabricated phantoms made from PVAL + 4% graphite powder (G4) showed good resemblance to extremely dense breast tissues (BIRADS D). Higher Cn, CNR, and SNR values were achieved with lower density breast equivalent phantoms. Density correlated positively with mean glandular dose (MGD) and the values of the MGD for the different categories of phantoms were within the acceptable limit of 3.0 mGy consistent with the ACR protocol.

Multicomponent biodegradable hydrogels based on natural biopolymers as environmentally coating membrane for slow-release fertilizers: Effect of crosslinker type

This work aims to explore the suitable crosslinker type for synthesizing multicomponent biodegradable hydrogels of cassava starch (CSt) grafted with acrylic acid (AA) semi-interpenetrated by natural rubber (NR)/polyvinyl alcohol (PVA) blend (CSt-g-PAA/NR/PVA, CSB semi-IPN hydrogel) as coating membranes for slow-release urea fertilizers. Three crosslinker types (ethylene glycol dimethacrylate (EGDMA), glutaraldehyde (GA) and N,N′- methylene-bis-acrylamide (MBA)) were employed to investigate their influences on the properties of CSB semi-IPN hydrogels. The results revealed that the different crosslinkers clearly exhibited different water-retention capacity, biodegradation, slow release and plant growth performance of the CSB semi-IPN hydrogels. The CSB-G2 hydrogel (crosslinked with GA at 2 wt%) remained higher water-retention at 30 days (20.2 %), greater rate of degradation (1.37 %/day) and better biosafety (OD600 = 2.26) compared to CSB-M2 and CSB-E2 hydrogels. After urea pellets were coated by CSB hydrogels and wax layers (UCSBw formulation), the urea release rates from the UCSBw-M2, UCSBw-E2 and UCSBw-G2 formulations in 30 days were 67.7 %, 68.7 % and 78.3 %, respectively, corresponding well with swelling ratio and pore size. Besides, the UCSBw-G2 formulation yielded the greater plant growth performance (height, leaf length and product weight) than other two formulations and commercial fertilizer. In conclusion, GA is the suitable crosslinker for synthesizing the CSB-g-PAA/NR/PVA hydrogels with high water-retention, excellent biodegradation, less negative impact on environments, acceptable slow-release rate, good biosafety and reasonable price for slow-release fertilizers.

Preparation and characterization of solid biopolymer electrolytes based on polyvinyl alcohol/cellulose acetate blend doped with potassium carbonate (K2CO3) salt

Solid polymer electrolytes (SPEs) based on blended polyvinyl alcohol (PVA) and cellulose acetate (CA) incorporated with potassium carbonate (K2CO3) salt were developed in this study. The electrolytes were prepared by incorporating salts into the polymers in various weight percent (wt.%) using solution casting technique. The developed electrolytes were characterized physicochemically and electrochemically using XRD, FTIR, FESEM, EIS, and LSV for crystal phase, chemical interaction, morphology, conductivity and potential window, respectively. Formation of complex between blended polymers and the salt has been established by the characterization results. The effect of PVA to CA ratio as well as the effects of salt contents on the performance of the prepared electrolytes was measured. It was found that the prepared SPE based on the polymer blend PVA:CA-80:20 (in weight) and with 20 wt% salt content produced the maximum conductivity of 5.30 × 10-4 Scm-1. The potential window of the optimized sample was tested and shows maximum potential window of 2.84 V. Based on the observed performance, SPEs based on PVA-CA-K2CO3 complex could serve as suitable electrolyte material for energy storage devices.

Preparation and Characterization of PANI/PVA Blends as Electrolyte Materials

This work presents a detailed study on the preparation and performance of polyaniline (PANI)/Polyvinyl alcohol (PVA) blend. The blends are prepared by the casting method at different weight ratios (1, 2, 3, 4, and 5 wt%). The structural morphology was characterized using scanning electron microscope SEM. The morphological analysis showed a uniform blend of PANI with PVA matrix. PVA exhibits lamellae structure of different shapes and dimensions. For 1% PANI, the results showed homogeneous blending, which decreases with an increase of the PANI ratio. Phase separation and semispherical region formation in the PVA matrix were seen. It was found that incompatibilities increase with increasing the PANI ratio. Also, the results proved in the blends scanning electron microscope anilinium cation – radical surfaces for an aggregate of different dimension and spherical shapes, which induced by surface tension. The electrical conductivity study of PANI/PVA blends and PVA reveals that PANI/PVA gives the conductivity of 10−4(cm.Ω)-1, while PVA presented the lowest conductivity with the value of 10−12 (cm.Ω)-1. The results also showed an increase in ionic conductivity with temperature and PANI weight ratio. The increase in electrical conduction with increasing temperatures is due to the negative thermal coefficient, this result is attributed to the polymer chains that act as traps for charge carriers, and when the temperature rises, the transfer mechanism will be reigned by the hopping process.

Towards multifunctional applications of Fullerene-filled (PVA-PEG) polymeric nanocomposite films: structural, optical, and electrical properties

Via casting method, Polyvinyl alcohol (PVA) and polyethylene glycol (PEG) blend matrix (80/20 wt %) based with fullerene (C60) (i.e., (PVA–PEG)/C60) polymeric nanocomposite (PNC) films have been prepared for optoelectronic devices. The X-ray diffractometer (XRD) and Fourier transform infrared (FTIR) analysis have been used to examine the structural behavior of these PNC films. The absorption coefficient derived from Beer-Lambert’s equation was used to determine energy bandgap (E g ), and Urbach’s energy (E u ) values. The nanocomposite films bandgap was lowered to 4.05 eV for indirect transition and 4.98 eV for direct transition. Because of surface plasmon absorption, the extinction index (k) rises with a doping concentration in nanocomposite films. The connections between bandgap and refractive index (n av ) were investigated using several empirical formulas to arrive at an average value for n. The nonlinear susceptibility χ (3) increased from 1.23 × 10−12 esu to 1.82 × 10−12 esu and from 7.099 × 10−13esu to 8.87 × 10−13 for indirect and direct transition, respectively. The nonlinear refractive index (n 2) increased from 2.146 × 10−11 esu to 3.062 × 10−11 esu and from 1.306 × 10−11esu to 1.59 × 10−11 esu for indirect and direct transition, respectively. The nanocomposites’ optical limiting performance and laser beam absorption capability were examined. Doping PVA–PEG with C60 in these nanocomposites at room temperature has been studied for its impact on complex dielectric permittivity, electric modulus characteristics, and AC electrical conductivity. The dielectric properties reduced with increasing frequency and raised with rising temperature and discussed as evidence of interfacial polarization. AC conductivity levels that varied with temperature followed Arrhenius’s law. According to our findings, the newly developed polymeric nanocomposite films are well-suited for use in electrical and optoelectronic devices.

High performance of the sodium‐ion conducting flexible polymer blend composite electrolytes for electrochemical double‐layer supercapacitor applications

AbstractHerein, we present the synthesis of a nanocomposite blend of polyvinyl alcohol (PVA), polyethylene glycol (PEG), sodium nitrate (NaNO3), and various weight percent of nanofillers, BaTiO3, using a simple standard solution casting technique. The prepared nanocomposites are characterized in detail via techniques such as X‐ray diffraction technique, field‐emission scanning microscope, FTIR, and Raman spectra for confirming the crystal structure, morphology, and chemical bond formation within the samples, respectively. The suitable ionic conductivity of prepared samples is in the range of 10−4–10−8 S/cm at room temperature. Further, its maximum electrochemical stability window is ~4.1 V, and the ionic transference number is about 0.96 (15 wt%) at room temperature. The results associated with the optimized polymer nanocomposite motivated us to check its practical applicability for supercapacitors. The cyclic voltammetry of the fabricated cell based on optimized polymer as separator cum electrolyte appears as a distorted rectangle with no redox peaks. The cell charge storage mechanism is explored to be the electric double layer (EDLC) in nature. The maximum specific capacitance exhibited by the cell is nearly 4.4 F/g at a scan rate of 3 mV/s. The energy and power densities delivered by the same cell are equal to 27.7 W h kg−1and 9972 W kg−1, respectively, which sustain for 100 cycles. The results of the designed cell reveal that both blend polymer composite electrolyte films and the composite electrode can be implemented to be used for EDLC supercapacitor.

Homogeneous and highly photoluminescent composites based on in-situ formed fluorophores in PVA blends

There is a strong demand for developing a simple, scalable, and transferable method to prepare homogeneous and highly photoluminescent composite for diverse applications. Herein, homogeneous composites were successfully synthesized by thermal annealing blends of polyvinyl alcohol, citric acid, and ethylenediamine. The composites exhibited intensive photoluminescence under excitation around 350 nm. Infrared, nuclear resonance, and optical characterizations suggest that diverse structures involving 5-oxo-1,2,3,5-tetrahydroimidazo-[1,2-α]-pyridine-7-carboxylic acid (IPCA) accounts for the high photoluminescence of the composites.

Hydrogels as Corneal Stroma Substitutes for In Vitro Evaluation of Drug Ocular Permeation.

Hydrogels are complex hydrophilic structures, consisting of crosslinked homopolymers or copolymers insoluble in water. Due to their controllable bio-physicochemical properties mimicking the morphology of the native extracellular matrix, they are a key part of a lot of research fields, including medicine, pharmaceutics, and tissue engineering. This paper was focused on the preparation and characterization of hydrogels from different blends of polyvinyl alcohol (PVA) with microcrystalline cellulose (MCC) and gelatin (GEL) at various ratios, and from gelatin and chitosan alone to understand their feasibility of utilizing as corneal stroma substitutes in permeability tests for drug candidate molecules in early stages of their development. The characterization was carried out by differential scanning calorimetry, electron microscopy (SEM), water content, mass loss, water permeability, wettability, and tensile stress–strain tests. After the physicochemical characterization, PVA/MCC blend and chitosan proved to be the most promising constructs, showing negligible mass loss after immersion in aqueous medium for two weeks and low hydrodynamic permeability. They were then employed in drug molecules permeation studies and these data were compared to that obtained through excised tissues. The results obtained showed that PVA/MCC hydrogels have similar mechanical and permeability properties to corneal stroma.

Sustainable Microbial and Heavy Metal Reduction in Water Purification Systems Based on PVA/IC Nanofiber Membrane Doped with PANI/GO

Effective and efficient removal of both heavy metal pollutants and bacterial contamination from fresh water is an open issue, especially in developing countries. In this work, a novel eco-friendly functional composite for water treatment application was investigated. The composite consisted of electrospun nanofiber membrane from blended polyvinyl alcohol (PVA)/iota carrageenan (IC) polymers doped with equal concentrations of graphene oxide (GO) nanoparticles and polyaniline (PANI). The effectiveness of this composite as a water purification fixed-bed filter was optimized in a batch system for the removal of cadmium (Cd+2) and lead (Pb+2) ions, and additionally characterized for its antimicrobial and antifungal properties and cytotoxicity effect. The fiber nanocomposite exhibited efficient antibacterial activity, with maximum adsorption capacity of about 459 mg g−1 after 120 min for Cd+2 and of about 486 mg g−1 after 90 min for Pb+2. The optimized conditions for removal of both metals were assessed by using a response surface methodology model. The resulting scores at 25 °C were 91.4% (Cd+2) removal at 117 min contact time for 89.5 mg L−1 of initial concentration and 29.6 cm2 membrane area, and 97.19% (Pb+2) removal at contact time 105 min for 83.2 mg L−1 of initial concentration and 30.9 cm2 nanofiber composite membrane. Adsorption kinetics and isotherm followed a pseudo-second-order model and Langmuir and Freundlich isotherm model, respectively. The prepared membrane appears to be promising for possible use in domestic water purification systems.

Preparation and characterization of polyvinyl alcohol/polylactic acid/titanium dioxide nanocomposite films enhanced by γ‐irradiation and its antibacterial activity

AbstractSynthesis of antimicrobial films for packaging applications is eminent fields of research. This study describes preparation of biodegradable Poly (PVA/PLA/TiO2) nanocomposite films was carried out by blending polyvinyl alcohol (PVA) and polylactic acid (PLA) doped with titanium dioxide (TiO2) nanoparticles using solution casting method and then irradiated by γ‐irradiation. The properties of the films were characterized by FT‐IR, XRD, FE‐SEM, TEM, TGA, and mechanical tests. The addition of TiO2 nanoparticles (0.8 wt%) explored considerable effects on thermal stability of the films. Results of FE‐SEM and TEM illustrated quite uniformly dispersion of TiO2 nanoparticles with average size of 17.5 nm. The effect of γ‐irradiation on nanocomposite films showed enhanced water resistance property and water vapor transmission rate. The water resistance property was achieved using PVA/PLA composition ratio (2/1). The antibacterial activity was evaluated against Staphylococcus aureus (S. aureus) and Escherichia coli (E. coli) bacteria. Poly(PVA/PLA/TiO2) nanocomposite film irradiated at 20 kGy displayed improved antibacterial activity and was selected for soil burial biodegradation tests. The biodegradation rate increased rapidly in the initial 12 weeks with significant changed morphology. The enhanced antibacterial efficiency and biodegradation property of the nanocomposite films suggest their possible use for development of packaging materials with low environmental impact.

Physical properties of polyvinyl alcohol (PVAL) gel materials as phantoms for mammography

This study evaluates the possibility of using polyvinyl alcohol (PVAL) composites as phantom material to simulate different densities of breast tissue for mammography based on their elastic properties. Three categories of PVAL gels were prepared by freezing and thawing 10 % water based PVAL (PVAL), ethanol and water based PVAL (PVAL/E) and a blend of PVAL with graphite powder (PVAL/G) solutions to mimic various breast densities. Young’s modulus (YM) of all samples was evaluated by puncture test using the texture analyser. The results recorded ranged from 0.93 to 4.79 kPa for all samples. The results indicate that the PVAL based phantoms examined could be used to simulate fatty and dense breast tissues based on the values of their densities and YM.

Use of niobium oxide nanoparticles as nanofillers in PVP/PVA blends to enhance UV–visible absorption, opto‐linear, and nonlinear optical properties

AbstractTransition metal oxide (TMO)—filled polymer films have numerous applications, including electromagnetic shielding and nonlinear optical devices. Nb2O5‐filled polyvinyl pyrrolidone (PVP)/polyvinyl alcohol (PVA) blend was prepared using a solution casting process. Pristine and nanocomposite films from these blends were studied. X‐ray diffraction (XRD), scanning electron microscopy (SEM), and Fourier infrared spectroscopy confirmed the formation of nanocomposites via interfacial interactions between the polymer chains and Nb2O5 nanoparticles. These nanoparticles influence the amorphous nature and transparency of the PVA/PVP blends. The improvement of Dopt (optical density) becomes particularly obvious in blended polymer films with considerable Nb2O5‐nanofiller concentrations. By increasing the weight percentage of Nb2O5, the probability of producing additional levels in the bandgap increased. The optical absorption coefficient of each nanocomposite film was less than 106 m−1, indicating indirect electron transfer. Thus, the indirect optical band‐gap declined from 3.9 to 1.9 eV as calculated from Tauc's and the absorption spectral fitting (ASF) formula. Additionally, the effects of Nb2O5 on the extinction coefficient, refractive index, high‐frequency (ε∞), and static‐frequency (εo) dielectrics have been reported. The nonlinear refractive index and optical susceptibilities (x1 and x3) were enhanced by increasing the Nb2O5 content in the blend. The penetration depth (δ) and optical limiting (OL) properties were also investigated. The developed nanocomposite materials could be used for advanced technology‐based devices such as reflective coatings, opto‐linear, and nonlinear optoelectronic applications.

Aloe vera Loaded (Polyvinyl Alcohol) Cryogel: Potential Wound Healer

The present work describes the preparation methodology of polyvinyl alcohol and Aloe vera hydrogels and their potential role in wound healing. Aloe vera is frequently used in treating many diseases due to its spectacular properties (anti-inflammatory, antiviral, antitumor and antibacterial) which assist in wound healing and help in treating many diseases a range of ailments. The designing of Aloe vera loaded polyvinyl alcohol (PVA) blend hydrogels (coined as cryogels) was done following repeated freeze-thaw cycles method. Characterization of the cryogels was done using some analytical techniques to study its properties and possible applications. The FTIR spectra shows that Aloe vera loaded PVA cryogels are interconnected by hydrogen bonding. Scanning electron microscope analysis established the porous nature of crogels. These hydrogels show water imbibing capacity, which depends on the experimental conditions and the chemical composition of the gel. The factors affecting the swelling ratio of crogels are amount of PVA, Aloe vera, number of Freez-Thaw cycles, pH and medium. The pore size of the cryogels also decreases with increasing number of freeze-thaw cycles. The Aloe vera-PVA cryogel is healing compatible with blood as there is less than 2% hemolysis.

Structural, Opto-Physical, Photoluminescence, and Optical Limiting Properties of Polyvinyl (Pyrrolidone and Alcohol) Blend Film Doped with Co-Metal

The optical properties of polyvinyl (pyrrolidine and alcohol) and PV(P/A) blend polymer have been improved using Co-metal as a filler for optoelectronic and optical shielding applications. The casting technique of solutions was used in order to prepare composite films with different Co-ratios (x: 0-18.5). XRD, FT-IR, SEM, and UV-visible spectrophotometry were operated to study the structure, morphology, and optical features of the flexible plain blend and composite films. The semi-crystalline nature of the films was influenced by the filler ratio of nanoparticles. Homogenous dispersion with some agglomeration of Co-particles has been observed in the host blend matrix. Then again, a successful interaction between the host matrix and particles was ensured by the FT-IR spectroscopic and XRD measurements. The cut-off absorbance edge of composite films is red-shifted from 200 nm (host blend) to 228 nm. The indirect transition optical band gap was confirmed from the Tauc's and optical dielectric loss calculations. Its value goes back from 5.15 eV (plain blend) to 4.43 eV for 18.5 wt% Co-blend composite film. An improvement in the extinction coefficient, optical conductivity, and refractive index of the composite films was achieved compared with the plain blend. The non-linear parameters of the composites were also enhanced. Photoluminescence (PL) emission spectra of PV(P/A) blend films doped with various weight percentages of Co-metal were examined at a wavelength of 750 nm. The optical shielding performance of the prepared composites is recommended for laser cut-off. Furthermore, the ability to tailor the optical properties of blend film makes it more effective for various applications including optical devices, non-linear optoelectronics, and reflective coating. Keywords: extinction coefficient, PV(P/A) polymer blend, transition band gap, photoluminescence, NL optical parameters, optical shielding.

Effect of cellulose nanocrystals (CNC) on PVA/CNC bio-nanocomposite film as potential food packaging application

The use of cellulose nanocrystals (CNC) and a polyvinyl alcohol (PVA) blend matrix as a potential in food packaging has been explored as a novel synthesis approach toward eco-friendly bio-nanocomposite films. CNC has been shown in multiple scientific studies to be a biodegradable and non-toxic material. However, CNC's sensitivity to humid environments and lack of thermostability has proven to be a key obstacle to its adoption in various industries, including food packaging. In this study, PVA/CNC bio-nanocomposite films at various CNC contents (2–6 wt%) were prepared by solvent casting method, and their properties were characterized by Optical Microscopy (OM), Field Emission Scanning Electron Microscopy (FESEM) and Ultra-visible (UV–vis) spectrophotometer. It was found that the addition of (2-6 wt%) of CNC within PVA improved the interfacial interactions between CNC and the blend to provide a clear micro-structure which was investigated through OM and FESEM. Additionally, the bio-nanocomposite films maintained high transparency level (transmittance of ∼90 % in the visible region in UV–vis), suggesting that the CNC were dispersed well within the PVA matrix. As a result, these superior eco-friendly structured bio-nanocomposites are likely to be effective in food packaging applications.

Adsorption of humic acid onto chitosan polyvinyl alcohol blend membrane from solution and second adsorption toward copper ions

Adsorption of humic acid onto chitosan polyvinyl alcohol blend membrane from solution and second adsorption toward copper ions