Search

Consumers and food industry stakeholders have expressed great interest in using simple, non‐destructive and inexpensive methods to control/maintain or monitor the freshness of perishable foods. The idea of smart packaging has been introduced to address these requirements satisfactorily, revolutionizing conventional food packaging. Vaccinium corymbosum (VC)–based carbon dots (CDs) and anthocyanin were matrixed on gelatin (GEL) to fabricate smart packaging film. The VC biowaste–derived carbon dots (VC‐CDs) were characterized using photoluminescence, fluorescence spectrometry, FTIR, antibacterial/antioxidant potential, TEM and XPS analysis. Fabricated films were subjected to physico‐chemical, antioxidant and optical properties, SEM, TGA simulation and in vivo food model system. The VC‐CDs exhibited excellent functional properties like ultraviolet (UV) blocking and antibacterial properties. The reinforcement with 1.5% VC‐CDs and 6% VC anthocyanins (VCA) in the GEL polymer matrix improved UV blocking (> 189%) properties and showed potent antioxidant potential (> 164%) compared to the neat GEL film. In vivo food packaging (minced pork, fish and shrimp) with films has shown that indicator films work efficiently and non‐destructively and monitor real‐time freshness. The GEL/VC‐CDs/VCA‐based active and intelligent films are expected to be applied as multifunctional nanocomposite packaging materials that can indicate quality changes in real time, maintain quality and prolong the shelf life of packaged foods. [ABSTRACT FROM AUTHOR]

In the present work, cellulose microfibers (CMFs) isolated from fallen autumn leaves of cherry plum (Prunus cerasifera pissardii nigra), white mulberry (Morus alba) and plane (Platanus orientalis) trees were characterized and used as reinforcement agents in sodium alginate‐based biodegradable films. Fourier transform infrared spectroscopy (FT‐IR) characterization showed that the CMFs were successfully isolated from the leaves with high purity. The extracted CMFs had a particle size ranging from 321.20 nm to 632.26 nm and negative zeta potential values (−27.33 to −21.40). The extraction yield of CMFs ranged from 19.53% to 26.00%. Incorporation of the leaf‐derived CMFs into sodium alginate based films (1%, w:w) increased their tensile strength (from 153.73 to 187.78 MPa) and elongation at break values (from 105.97% to 89.90%) and significantly decreased oxygen (from 121.46 to 75.56 meq kg‐1) and water vapor permeabilities (from 2.36 to 1.60 g mm h−1 m−2 kPa−1)(p < 0.05). Furthermore, the supplementation of CMFs into the biopolymer matrix had no significant effect on the color (L*: 85.35–85.67; a*: −0.75‐0.71; b*: 4.23–4.94) and moisture content (44.64–48.42%) of the film samples, although the thickness increased (40.33–94.66 μm). Scanning electron microscopy (SEM) images showed that CMFs were homogeneously dispersed in the film matrix. Overall, this study confirms that fallen cherry plum, white mulberry, and plane leaves are valuable sources of CMFs which could be used in the manufacturing of biodegradable nanocomposite films as reinforcement agents. [ABSTRACT FROM AUTHOR]

Dielectric materials with high energy storage density are essential for developing adaptable energy storage devices to address the growing demand for electrical energy. This paper design introduces low-loaded BNNS nanosheets as second-phase fillers and BT@SiO 2 nanoparticles to form a dual-filler system to achieve functional complementarity. An easy spin-coating technique was used to successfully prepare BNNS/BT@SiO 2 /P(VDF-HFP) nanocomposites. The high polarization of the core-shell structure BT@SiO 2 and the wide bandgap of the "barrier surface" structure BNNS were utilized to ensure the increase of ε r and the maintenance of E b to synergistically contribute to increase energy density without sacrificing the mechanical properties of polymer matrix. Due to the homogeneous and dense microstructure and the important contribution of the complementary effect of the dual-filler system, BNNS/BT@SiO 2 /P(VDF-HFP) nanocomposites show good synergistic effects in maintaining high ε r , low tanδ, and high E b. At 3400 kV/cm, the energy density of 11.06 J/cm3 was attained by the nanocomposite with 3 wt% BNNS content. This is about 922 % of the best commercial BOPP film (1.2 J/cm3). BNNS/BT@SiO 2 /P(VDF-HFP) nanocomposite also maintained an attractive energy density (11.16 J/cm3 and 9.02 J/cm3) at 75 °C and 115 °C. Both phase-field breakdown simulations results and experimental results verify the advantages of nanocomposites constructed by synergistic dual-filler composites in improving the energy density. This work provides a simple and scalable strategy for obtaining high-energy-storage dielectric nanocomposites. [ABSTRACT FROM AUTHOR]

This study investigated the synergistic impact of montmorillonite (MMT) and starch nanocrystals (SNCs) on gluten-loaded chitosan films, influencing the shelf stability of fresh paneer. The combination of chitosan in gluten and SNCs/MMT yielded films with uniform rheology, showcasing superior water resistance, mechanical strength, surface morphology, and antioxidant properties. Notably, compared to unpackaged paneer, those wrapped in these nanocomposite films exhibited an extended shelf life. Films produced from MMT/chitosan (GML2) retained higher moisture (68.37 to 53.12%) and titratable acidity (0.17 to 2.12%) compared to other samples. Consequently, textural properties, including hardness, springiness, chewiness, and gumminess, correlated with moisture loss, affirming the wholesomeness of paneer packaged in GML2, followed by SNCs/chitosan (GSL2). The longer shelf-life of paneer was co-related with minimal increase in free fatty acids and tyrosine content of GML2 and GSL2, lead reduced lipolysis and proteolysis. The microbiological analysis demonstrated the resilience of paneer in GML2 and GSL2, with total yeast/mold count (4.00 logCFU/g and 5.00 logCFU/g) and total plate count (6.00 logCFU/g and 6.00 logCFU/g) maintained up to the 12th day. Overall, physico-chemical attributes confirmed the superior physical and nutritional quality of paneer packaged in GML2 and GSL2 compared to the control, effectively preserving its freshness for 12 days. Highlights: Gluten-based films reinforced with MMT/chitosan and SNCs/chitosan were developed. Novel Gluten-based Bionanocomposites enhance the shelf stability of Paneer. MMT/chitosan and SNCs/chitosan demonstrated textural stability in Paneer. Bionanocomposites preserved paneer in fresh condition for up to 12 days. [ABSTRACT FROM AUTHOR]

In this study, nanocomposite films consisting of potato starch (PS), layered double hydroxide (LDH), and microcrystalline cellulose (MCC) were synthesized using the solution casting method. The MCC particles were used to stabilize the dispersion of LDH during film preparation. The study investigated the effect of LDH particles on the optical, electrical, dielectric, mechanical, and barrier properties of PS/MCC films. The X-ray diffraction and scanning electron microscopy analysis confirmed that the PS/MCC/LDH ternary films had a partially intercalated and partially exfoliated structure. FTIR and Raman spectroscopy analysis revealed the formation of new hydrogen bonds between PS hydroxyl groups and nanoparticles. The direct optical band gap decreased from 5.80 to 5.44 eV with increasing LDH content. The refractive index, optical conductivity and optical dielectric constant all improved with increasing LDH content. The presence of MCC and LDH had little effect on the optical clarity of the starch-based films. The improving of dielectric properties was demonstrated by decreasing the dielectric loss tangent with increasing LDH content. The addition of 1%, 3%, and 5% by weight of LDH to the pure starch PS film resulted in significant improvements in tensile strength and tensile modulus of the ternary nanocomposites. In addition, the water solubility of the nanocomposites decreased with the addition of LDH. The principal component analysis results confirmed the positive effect of higher biopolymer content on these properties. The results of the study confirm that PS/MCC/LDH nanocomposites films can be used in optical and electronic applications. [ABSTRACT FROM AUTHOR]

Abstract This study investigates the development of novel nanocomposite films based on a blend of polyethylene oxide (PEO) and polyvinyl alcohol (PVA) loaded with varying weight percentages of copper cobaltite nanoparticles (CuCo2O4 NPs). The primary objective was to fabricate these nanocomposites using a solution casting technique and explore the influence of CuCo2O4 content on their structural, optical, electrical, and dielectric properties. Spinel-type CuCo2O4 NPs were synthesized via the hydrothermal method and incorporated into the PEO/PVA blend. X-ray diffraction (XRD) analysis revealed the transformation of the polymer matrix towards an amorphous state with increasing CuCo2O4 content. UV–Vis spectroscopy studies demonstrated a decrease in both the direct and indirect band gaps of the nanocomposites, suggesting potential applications in optoelectronic devices. Impedance spectroscopy measurements revealed a significant enhancement in ionic conductivity (three orders of magnitude higher than the pristine blend) for the nanocomposite film containing 1.8 wt% CuCo2O4. The real permittivity (ε′) and imaginary permittivity (ε″) of the polymer nanocomposites exhibited a decrease with increasing frequency due to the interplay of various polarization mechanisms. Notably, incorporating 1.8 wt% CuCo2O4 nanoparticles led to a remarkable improvement in energy density compared to the pristine blend. Additionally, a significant decrease in the potential barrier was observed. These findings demonstrate the successful fabrication of PEO/PVA-CuCo2O4 nanocomposite films with enhanced optical, electrical, and dielectric properties. The observed improvements suggest promising applications for these materials in energy storage devices and potentially in optoelectronic devices like light-emitting diodes.

This study investigates the development of novel nanocomposite films based on a blend of polyethylene oxide (PEO) and polyvinyl alcohol (PVA) loaded with varying weight percentages of copper cobaltite nanoparticles (CuCo2O4 NPs). The primary objective was to fabricate these nanocomposites using a solution casting technique and explore the influence of CuCo2O4 content on their structural, optical, electrical, and dielectric properties. Spinel-type CuCo2O4 NPs were synthesized via the hydrothermal method and incorporated into the PEO/PVA blend. X-ray diffraction (XRD) analysis revealed the transformation of the polymer matrix towards an amorphous state with increasing CuCo2O4 content. UV–Vis spectroscopy studies demonstrated a decrease in both the direct and indirect band gaps of the nanocomposites, suggesting potential applications in optoelectronic devices. Impedance spectroscopy measurements revealed a significant enhancement in ionic conductivity (three orders of magnitude higher than the pristine blend) for the nanocomposite film containing 1.8 wt% CuCo2O4. The real permittivity (ε′) and imaginary permittivity (ε″) of the polymer nanocomposites exhibited a decrease with increasing frequency due to the interplay of various polarization mechanisms. Notably, incorporating 1.8 wt% CuCo2O4 nanoparticles led to a remarkable improvement in energy density compared to the pristine blend. Additionally, a significant decrease in the potential barrier was observed. These findings demonstrate the successful fabrication of PEO/PVA-CuCo2O4 nanocomposite films with enhanced optical, electrical, and dielectric properties. The observed improvements suggest promising applications for these materials in energy storage devices and potentially in optoelectronic devices like light-emitting diodes. [ABSTRACT FROM AUTHOR]

A lot of demand exists for multifunctional TPU that can provide enhanced performance to address a variety of inflatable application needs. To develop multifunctional nanocomposite films for such uses, synthesized zinc stannate (ZnSnO3) nanoparticles are integrated for the first time in a thermoplastic polyurethane (TPU) matrix. ZnSnO3 was synthesized using hydrothermal method. The morphological analysis vividly displayed the nanocubic structures. As‐synthesized nano ZnSnO3 was added as a nanofiller at varied concentration from 2 to 10 wt% in TPU and nanocomposite films were prepared by solvent intercalation and casting method. These films were thoroughly examined for their multifunctional properties such as UV protection, helium gas barrier and infrared emissivity. Mean value of UV protection factor was improved by 75% at 10 wt% loading of ZnSnO3 whereas 23% improvement was observed in helium gas barrier. Moreover, a good correlation of experimental data with various theoretical models of gas permeability was obtained at lower volume fraction of ZnSnO3. IR emissivity value also showed improvement from 0.802 to 0.842. Thus, the developed TPU‐ZnSnO3 nanocomposite films exhibited a significant improvement in multiple functional properties with improved tensile strength at optimized loading of 6 wt% of ZnSnO3. Highlights: UPF mean value of ZnSnO3 incorporated TPU film has been improved by 67%.Helium gas barrier has been improved by approximately 23% at 6 wt% loading.TPU film exhibited improved properties at optimized loading of 6 wt% of ZnSnO3.Nanocomposite TPU film can be employed in various weathering inflatables. [ABSTRACT FROM AUTHOR]

The fabrication of ultra-tough biodegradable nanocomposite films with antibacterial activity and antioxidant properties remains a huge challenge. Herein, we developed a super-tough antibacterial biodegradable poly(vinyl alcohol) (PVA) nanocomposite film by simply introducing highly effective antibacterial agent PDA@LS-Ag into PVA matrix. The antibacterial agent PDA@LS-Ag was synthesized from the mussel-inspired polydopamine (PDA) and green biomass sodium lignosulfonate (LS) via a facile microwave-assisted reduction strategy, in which PDA played the role of reducing agent and LS performed as the dispersant. The tensile strength of the PVA nanocomposite film with 5 wt% addition of PDA@LS-Ag reached up to 131.7 MPa, which was far higher than most of engineering plastics. The excellent mechanical performance was resulted from the synergistic effect of the unique nanoscale phase-separation structure and the dense hydrogen bonds between the PDA@LS-Ag nanoparticles and PVA matrix. Owing to the existence of silver nanoparticles and rich phenolic hydroxyl groups, the PDA@LS-Ag nanoparticles also endued the composite film with good antibacterial activity, outstanding antioxidant activity, and UV-shielding properties. As the biomass LS, PDA, and the PVA matrix are all biodegradable, this work provides a feasible way for preparing highly strong and super-tough biodegradable nanocomposite films with antibacterial and antioxidant properties. [ABSTRACT FROM AUTHOR]

In the past decades, the use of plastic films based on synthetic polymers increased rapidly due to features such as ease of use, and reasonable cost. Today, environmental problems such as the non-biodegradability of synthetic polymers on the one hand, as well as problems caused by the safety of food packaged with synthetic polymers on the other hand, have led to the development of research on the use of natural polymers in the production of biodegradable films. One solution is the application of nanotechnology in the production of nanocomposite films to solve the practical problems of biodegradable films based on protein and polysaccharide biopolymers. The production of nanocomposite films with photocatalytic activities, in addition to having antioxidant and antimicrobial benefits of bioactive compounds, increases structural strength and it also affects the mechanical characteristics and physical and chemical properties of edible films. The aim of this review is to overview the general and current scenario of protein and polysaccharide based nanocomposite films with photocatalytic activity. [ABSTRACT FROM AUTHOR]

A novel quasi 1–2 type magnetoelectric (ME) nanocomposite films composted of one‐dimensional CoFe2O4 nanofibers and two‐dimensional PbZr0.2Ti0.8O3 films on flexible mica substrate have been designed and fabricated. The ME coupling effects have been greatly enhanced due to the release of the clamping effect and the high strain transfer efficiency between the large aspect ratio of the nanofibers and ferroelectric thin films. The release of the clamping effect was confirmed by reducing the thickness of the mica substrate, in which the piezoelectric coefficient and ME coupling coefficient of the nanocomposite films have been greatly boosted by the decrease in the mica thickness. A large direct ME coupling coefficient of 630 mV/(cm Oe) and a converse ME coupling coefficient of 1.43 × 10−8 s/m have been achieved in the quasi 1–2 nanocomposite film with a substrate thickness of 25 µm. Furthermore, the stain‐mediated ME coupling was revealed by magnetic field/electric field‐induced local ferroelectric/magnetic domain switching dynamics. [ABSTRACT FROM AUTHOR]

In this study, we explored the behavior of protonated polyaniline/graphene oxide (PANI‐CSA/GO) nanocomposite films with varying GO concentrations, focusing on the novel phenomenon of explosive percolation. We observed a significant increase in electrical conductivity at the explosive percolation threshold, attributed to the emergence of a percolating metallic pathway. This discovery positions PANI‐CSA/GO films as promising materials for various electronic and electrical engineering applications. Additionally, the films demonstrated consistent and repeatable photoconductivity, showing potential for use in high‐performance UV‐photodetectors, photoactive layers in solar cells, light‐emitting diodes, and energy storage devices. Structural analyses using fourier transform infrared spectroscopy (FTIR) and x‐ray diffraction (XRD) confirmed successful GO incorporation within the PANI‐CSA matrix. Different morphological features were observed depending on the GO volume fraction, with increased GO enhancing thermal stability in the conductive zone. Our findings highlight the immense potential of PANI‐CSA/GO nanocomposite films in advanced electronic applications, emphasizing their novel conductive and photoconductive properties and improved thermal stability. [ABSTRACT FROM AUTHOR]

This paper describes the improvements in microwave absorbency and other functional properties of silicone rubber-based nanocomposite sheets with iron (Fe)- and nickel (Ni)-deposited nanographite (NG). NG was synthesized using the ball milling method and then acid functionalized. The deposition was performed on acid-functionalized NG dispersed in an electrochemical bath containing Fe and Ni salts in a designed fluidized bed reactor system. The electrolyte concentration, stirring speed, applied current, and time of electrolysis were optimized. X-ray diffraction, Fourier transform infrared spectroscopy, Brenner–Emmet–Teller analysis, transmission electron microscopy, scanning electron microscopy, and atomic force microscopy were used to characterize the structural as well as morphological properties of the material. The applied current, average particle size, and density of the electrolyte–powder suspension have a significant impact on the material's morphology and microwave absorption capabilities. To measure tensile strength, electrical impedance, and microwave absorption in the 2–20 GHz range, co-deposited nanographite was mixed in a silicone rubber matrix and molded into 1.00–2.00 mm thick nanocomposite sheets. The nanocomposite sheets demonstrated a − 15 dB reflection loss in the 9–13 GHz frequency band with an absorber thickness of 1.24 mm. [ABSTRACT FROM AUTHOR]

In this work, novel nanocomposite films based on babassu coconut mesocarp and zinc oxide nanoparticles (ZnO NPs), synthesized by a green route, were produced for application as food packaging films. The films were prepared using the casting method containing different contents of ZnO NPs (0 wt%, 0.1 wt%, 0.5 wt%, and 1.0 wt%). The films were characterized by Fourier-transform infrared spectroscopy (FTIR), X-ray diffraction (XRD), thermogravimetric analysis (TGA), scanning electron microscopy (SEM), instrumental color analysis, and optical properties. The water vapor permeability (WVP) and tensile strength of films were also determined. The antimicrobial activity of the films against cooked turkey ham samples contaminated with Staphylococcus aureus was investigated. The results showed that incorporating ZnO NPs into babassu mesocarp matrices influenced the structure of the biopolymer chains and the color of the films. The BM/ZnO-0.5 film (0.5 wt% ZnO NPs) showed better thermal, mechanical, and WVP properties. Furthermore, the synergistic effect of babassu mesocarp and ZnO NPs in the BM/ZnO-0.5 film improved the antimicrobial properties of the material, reducing the microbial count of S. aureus in cooked turkey ham samples stored under refrigeration for 7 days. Thus, the films produced in this study showed promising antimicrobial packaging materials for processed foods. [ABSTRACT FROM AUTHOR]

Several new-generation synthetic biodegradable polymers have been developed specifically for biomedical applications in the last two decades. Polycaprolactone (PCL) was chosen as the polymer matrix in this study because it is known for its ease of synthesis, commercial availability, and excellent biocompatibility. Carbon Quantum Dots (CQDs), one of the carbon nanostructures with superior properties, were used as fillers to produce PCL film nanocomposites with improved biotribological properties. The biotribological behavior of (Sample of KCQDs produced from Rosehip) K-CQDs filled PCL matrix nanocomposite films containing 0.3 and 2.0 wt. % KCQDs filler were investigated in sliding against an alumina (Al2O3) counterface by a constant loading (2.5 N) and sliding speed (1.7 cm s-1) experiments carried out in a reciprocating friction testing machine in 0.154 M isotonic salt solution. PCL/K-CQDs-2.0 film had lower friction coefficient value (0.304) with a 70% decrease, and wear rate (0.00051 mm3/Nm; 65% decrease) compared to PCL/K-CQDs-0.3. The surface images of PCL/K-CQDs-2.0 film after the wear test indicated that the wear width trace and the adhesive wear traces decreased. In addition, the absence of cracks on the worn surface showed that both films were resistant to plastic deformation. [ABSTRACT FROM AUTHOR]

The diversity of species in Amazonia is exceptionally vast and unique, and it is of great interest for industry sectors to explore the potential of derivatives with functional properties for packaging applications. This study proposes the functionalization of cellulose micro/nanofibril (MFC/NFC) suspensions from Heteropsis flexuosa with andiroba oil to produce films with packaging potential. MFC/NFC was produced by using mechanical fibrillation from suspensions of H. flexuosa fibers. Proportions of 1, 3, and 5% of andiroba oil were added to make films with concentrations of 1% (m/m). Suspensions with andiroba oil provided greater viscosity, with changes in the physical properties of the films. Functionalization with andiroba oil provided films with lower degradation in water, greater contact angle, and lower wettability despite high permeability to water vapor. The films with 1% andiroba oil showed a hydrophobic characteristic (contact angle > 90°) and greater puncture resistance (6.70 N mm−1). Films with 3% oil showed a more transparent appearance and high biodegradation, while 1% oil generated more opaque films with a higher thermal degradation temperature and high antioxidant activity. It was concluded that films produced from H. flexuosa fibers functionalized with andiroba oil showed packaging potential for light, low-moisture products due to their adequate thermal and barrier characteristics. [ABSTRACT FROM AUTHOR]

This study aimed to synthesize silver nanoparticles with sophorolipids (AgNP‐SL) and develop starch nanocomposite films with improved properties to be explored in food packaging applications. AgNP‐SL were spherical and highly stable, with an average size of 61.46 nm. They also demonstrated potent antibacterial action against Escherichia coli and Staphylococcus aureus, revealing its promising application for antimicrobial packaging. The addition of AgNP‐SL into films resulted in color changes, which could contribute to a better UV‐barrier capacity. Nanoparticles and tartaric acid incorporation resulted in a heterogeneous matrix, suggesting chemical interactions between the compounds and the biopolymer. The nanocomposite films presented thermal stability, enhanced flexibility, and antimicrobial action against E. coli, Salmonella enterica serovar Enteritidis, and S. aureus. The combination of AgNP‐SL and tartaric acid resulted in pronounced bactericidal properties. The results demonstrate the great potential of these nanocomposite films as an effective packaging material against foodborne pathogens. [ABSTRACT FROM AUTHOR]

To enhance the various properties of polyvinyl alcohol (PVA), varying concentrations of carboxy-functionalized graphene (CFG) were employed in the preparation of CFG/PVA nanocomposite films. FTIR and XRD analyses revealed that CFG, in contrast to graphene, not only possesses carboxylic acid group but also exhibits higher crystallinity. Mechanical testing indicated a notable superiority of CFG addition over graphene, with optimal mechanical properties such as tensile and yield strengths being achieved at a 3% CFG concentration. Relative to pure PVA, the tensile strength and yield strength of the composite increased by 2.07 and 2.01 times, respectively. XRD analysis showed distinct changes in the crystalline structure of PVA with the addition of CFG, highlighting the influence of CFG on the composite structure. FTIR and XPS analyses confirmed the formation of ester bonds between CFG and PVA, enhancing the overall performance of the material. TGA results also demonstrated that the presence of CFG enhanced the thermal stability of CFG/PVA nanocomposite films. However, analyses using scanning electron microscopy and transmission electron microscopy revealed that a 3% concentration of CFG was uniformly dispersed, whereas a 6% concentration of CFG caused aggregation of the nanofiller, leading to a decrease in performance. The incorporation of CFG significantly enhanced the water vapor and oxygen barrier properties of PVA, with the best performance observed at a 3% CFG concentration. Beyond this concentration, barrier properties were diminished owing to CFG aggregation. The study further demonstrated an increase in electrical conductivity and hydrophobicity of the nanocomposites with the addition of CFG. Antibacterial tests against E. coli showed that CFG/PVA nanocomposites exhibited excellent antibacterial properties, especially at higher CFG concentrations. These findings indicate that CFG/PVA nanocomposites, with an optimized CFG concentration, have significant potential for applications requiring enhanced mechanical strength, barrier properties, and antibacterial capabilities. [ABSTRACT FROM AUTHOR]

Biodegradable films based on a blend of Peruvian tunta starch (TS) and tara gum (TG) (95:5) reinforced with TS nanocrystals (NC) were prepared using the casting method. The effect of ultraviolet (UV)-irradiation time (60 and 120 min) and the NC concentration (0, 5, and 10 g/100 g biopolymers) on the physicochemical and disintegrability properties of nanocomposite TS:TG films were investigated. Tensile strength and Young's modulus were increased from 4 to 14 MPa and 14 to 600 MPa, respectively; meanwhile, the elongation was reduced by about 90% by increasing NC amount, mainly at lower UV-time. The color parameters and the UV–vis light barrier showed a significant (p <.05) variation mainly due to the NC effect. The higher the NC content, the lower the moisture barrier (p <.05). Neither NC nor UV time significantly impacted the moisture content, water solubility, crystallinity, or chemical composition. SEM micrographs showed a roughness increase in the films' microstructure with a marked difference among treatments. All films were disintegrated more than 80% after 5 days of burying under composting conditions. The UV-irradiation combined with TS nanocrystal reinforcement caused a significant enhancement of some TS:TG films' properties, suggesting their possible use as eco-friendly packaging. [ABSTRACT FROM AUTHOR]

This paper presents a study of the electrical and mechanical properties of polystyrene (PS)/carbon nanotube (CNT) composites prepared using the doctor blade technique. The nanocomposite films of PS/CNT were prepared by casting a composite solution of PS/CNT in tetrahydrofuran (THF) on a glass substrate using a doctor blade and drying in an oven. The nanocomposite films were then characterized using a tensile test and the four-point probe method to evaluate their mechanical properties and electrical conductivity. The experimental results were used to analyze the unpredicted behavior of the nanocomposite films. The experimental results showed that the electrical conductivity of the nanocomposite films became almost insensitive or unmeasurable with increasing CNT content for very dilute PS–THF solutions. In contrast, at higher PS concentrations, film conductivity increased to a given CNT threshold and then decreased. Based on PS–THF viscosity–concentration data, a discussion is elaborated that partially justifies the experimental results. [ABSTRACT FROM AUTHOR]

The successful preparation of flexible PPy/CuO nanocomposite consisting of polypyrrole (PPy) with copper oxide (CuO) was achieved. The structural analysis of PPy and PPy/CuO was conducted by EDX, SEM, TEM, and FTIR techniques, which providing the successful fabrications of PPy/CuO nanocomposite films. The EDX analysis of thePPy/CuO nanocomposite reveals the presence of characteristic peaks corresponding to the elements of C, Cu, N, and O, with weight percentages of 47.46%, 9.05%, 19.08%, and 24.41%, respectively. The obtained results provide confirmation that the PPy/CuO nanocomposite film does not exhibit the presence of any impurity components. The FTIR noticed that all peaks of PPy spectrum also showed in the spectra of PPy/CuO nanocomposite films with a little shifts in peaks, in which these shifts increase with increasing contents of CuO nanoparticles. The findings of this study indicate that there are interactions occurring between PPy/CuO. Furthermore, SEM was employed to elucidate the morphological of the (PPy) and PPy/CuO. The SEM demonstrate that the copper oxide (CuO) are evenly distributed within the nanocomposite films. Using Tauc's relation, the band gap and Urbach energy of PPy and PPy/CuO films. were determined. The addition of varying concentrations (2.5%, 5%, and 10%) of CuO to PPy increase the Urbach tail of PPy, resulting in energy values of 1.08 eV, 1.11 eV, and 1.13 eV, correspondingly. Simultaneously, the presence of CuO causes reduction in the band gap of PPy from 3.42 eV to 3.35 eV, 3.32 eV, and 3.30 eV. Consequently, the incorporation of CuO into PPy/CuO composite films induces both structural and optical modifications, rendering these films suitable for utilization in optoelectronic devices. [ABSTRACT FROM AUTHOR]

Charge injection and conduction are fundamental phenomena that occur in dielectric materials when subjected to both low and high electric fields. This paper delves into the exploration of various conduction mechanisms, including space-charge-limited current (SCLC), Schottky charge injection, Poole–Frenkel, and hopping charge conduction, to elucidate the prevailing conduction mechanism in single and multilayer polyimide (PI)/SiO2 nanocomposite films across a range of temperatures. At elevated electric field strengths, the conduction behavior transitions from ohmic to exhibiting a non-linear current–voltage dependence. The investigation highlights that PI nanocomposite films display distinct conduction behaviors contingent on both the applied electric field and temperature conditions. The insights derived from this study provide valuable empirical groundwork and explanations for conducting current measurements in PI-based insulation systems, particularly in applications such as motor insulation for electric vehicles. [ABSTRACT FROM AUTHOR]

Lignin-containing cellulose nanofibers (LCNFs) from bamboo were prepared by choline chloride–lactic acid solvent treatment at 110–130∘C in combination with ultrasonication. Effects of LCNFs dosages on UV-blocking property, mechanical property, thermal stability and water vapor barrier property of LCNFs/PVA composite film were determined by UV spectrophotometer, universal mechanical testing machine, thermogravimetric analysis and weightlessness method, respectively. The results indicated that PVA film composited 10% LCNFs obtained from 120∘C showed best properties. As compared to pure PVA film, the UV-blocking property of composite film increased from 30% to 53%. LCNFs addition enhanced mechanical properties, resulting increment of tensile strength from 42 MPa to 81 MPa and elongation at break from 3% to 9%, respectively. LCNFs also introduced 2.4 times increment of water vapor barrier property of PVA film. The LCNFs/PVA composite films not only have excellent thermal stability and mechanical properties but also have UV-resistance and water vapor barrier properties. It provides a new idea for replacing some petroleum-based packaging materials and also shows the great potential of LCNFs materials. [ABSTRACT FROM AUTHOR]

In this study, waterborne polyurethane acrylate (WPUA)/MXene nanocomposite films with varying MXene loadings were fabricated using UV-curing technology, where MXene (Ti3C2Tx) was employed as a nanofiller. The microstructure and chemical structure of the WPUA/MXene nanocomposite films were examined by XRD and FTIR, respectively. The water contact angle testing demonstrated that the incorporation of MXene into the nanocomposite films led to an increase in their hydrophilic properties. The tensile strength, the elongation at break, and Young's modulus of the WPUA/MXene nanocomposite coatings exhibited an initial increase followed by a decrease with increasing MXene loadings. Compared to the pure WPUA film, the tensile strength and elongation at break of nanocomposites with 0.077 wt% MXene loading reached their maximum values, which increased by 39.9% and 38.5%, respectively. Furthermore, the glass transition temperature and the thermal stability were both enhanced by MXene to some extent. This study introduces a novel method for utilizing MXene in UV-curable waterborne coatings. [ABSTRACT FROM AUTHOR]

Optimized Bentong ginger (BG) extract using ultrasonic‐assisted extraction (UAE) was incorporated in hybrid carrageenan/nanocomposite biopolymers for active packaging films. The design of experiments based on central composite design was applied for the study of the operating parameters (amplitude, sonication time, and solvent concentration) of UAE in the recovery of phenolic compounds from BG. Optimized extracts were analyzed for the content of 6‐gingerols in liquid chromatography quadrupole time‐of‐flight mass spectrometry and formulated in carrageenan/nanocellulose hybrid films for active packaging applications. The mechanical properties of the films and release behavior of antioxidant compounds into food simulants were investigated. The optimized UAE BG extract was found efficacious as an antioxidant agent in active packaging. [ABSTRACT FROM AUTHOR]

The need for integrated passive devices (IPDs) emerges from the increasing consumer demand for electronic product miniaturization. Metal-insulator-metal (MIM) capacitors are vital components of IPD systems. Developing new materials and technologies is essential for advancing capacitor characteristics and co-integrating with other electronic passives. Here we present an innovative electrochemical technology joined with the sputter-deposition of Al and Zr layers to synthesize novel planar nanocomposite metal-oxide dielectrics consisting of ZrO2 nanorods self-embedded into the nanoporous Al2O3 matrix such that its pores are entirely filled with zirconium oxide. The technology is utilized in MIM capacitors characterized by modern surface and interface analysis techniques and electrical measurements. In the 95–480 nm thickness range, the best-achieved MIM device characteristics are the one-layer capacitance density of 112 nF·cm−2, the loss tangent of 4·10−3 at frequencies up to 1 MHz, the leakage current density of 40 pA·cm−2, the breakdown field strength of up to 10 MV·cm−1, the energy density of 100 J·cm−3, the quadratic voltage coefficient of capacitance of 4 ppm·V−2, and the temperature coefficient of capacitance of 480 ppm·K−1 at 293–423 K at 1 MHz. The outstanding performance, stability, and tunable capacitors' characteristics allow for their application in low-pass filters, coupling/decoupling/bypass circuits, RC oscillators, energy-storage devices, ultrafast charge/discharge units, or high-precision analog-to-digital converters. The capacitor technology based on the non-porous planar anodic-oxide dielectrics complements the electrochemical conception of IPDs that combined, until now, the anodized aluminum interconnection, microresistors, and microinductors, all co-related in one system for use in portable electronic devices. [ABSTRACT FROM AUTHOR]

In this work, novel nanocomposite films based on babassu coconut mesocarp and zinc oxide nanoparticles (ZnO NPs), synthesized by a green route, were produced for application as food packaging films. The films were prepared using the casting method containing different contents of ZnO NPs (0 wt%, 0.1 wt%, 0.5 wt%, and 1.0 wt%). The films were characterized by Fourier-transform infrared spectroscopy (FTIR), X-ray diffraction (XRD), thermogravimetric analysis (TGA), scanning electron microscopy (SEM), instrumental color analysis, and optical properties. The water vapor permeability (WVP) and tensile strength of films were also determined. The antimicrobial activity of the films against cooked turkey ham samples contaminated with Staphylococcus aureus was investigated. The results showed that incorporating ZnO NPs into babassu mesocarp matrices influenced the structure of the biopolymer chains and the color of the films. The BM/ZnO-0.5 film (0.5 wt% ZnO NPs) showed better thermal, mechanical, and WVP properties. Furthermore, the synergistic effect of babassu mesocarp and ZnO NPs in the BM/ZnO-0.5 film improved the antimicrobial properties of the material, reducing the microbial count of S. aureus in cooked turkey ham samples stored under refrigeration for 7 days. Thus, the films produced in this study showed promising antimicrobial packaging materials for processed foods.

ABSTRACTThe need for integrated passive devices (IPDs) emerges from the increasing consumer demand for electronic product miniaturization. Metal-insulator-metal (MIM) capacitors are vital components of IPD systems. Developing new materials and technologies is essential for advancing capacitor characteristics and co-integrating with other electronic passives. Here we present an innovative electrochemical technology joined with the sputter-deposition of Al and Zr layers to synthesize novel planar nanocomposite metal-oxide dielectrics consisting of ZrO2 nanorods self-embedded into the nanoporous Al2O3 matrix such that its pores are entirely filled with zirconium oxide. The technology is utilized in MIM capacitors characterized by modern surface and interface analysis techniques and electrical measurements. In the 95–480 nm thickness range, the best-achieved MIM device characteristics are the one-layer capacitance density of 112 nF·cm−2, the loss tangent of 4·10−3 at frequencies up to 1 MHz, the leakage current density of 40 pA·cm−2, the breakdown field strength of up to 10 MV·cm−1, the energy density of 100 J·cm−3, the quadratic voltage coefficient of capacitance of 4 ppm·V−2, and the temperature coefficient of capacitance of 480 ppm·K−1 at 293–423 K at 1 MHz. The outstanding performance, stability, and tunable capacitors’ characteristics allow for their application in low-pass filters, coupling/decoupling/bypass circuits, RC oscillators, energy-storage devices, ultrafast charge/discharge units, or high-precision analog-to-digital converters. The capacitor technology based on the non-porous planar anodic-oxide dielectrics complements the electrochemical conception of IPDs that combined, until now, the anodized aluminum interconnection, microresistors, and microinductors, all co-related in one system for use in portable electronic devices.

In order to enhance the mechanical properties of UV-curable epoxy acrylate (EA)-based coatings, 3-(trimethoxysilyl)propyl methacrylate modified aramid nanofibers (T-ANFs) were synthesized and used as nanofillers to prepare EA/T-ANF nanocomposite films. The morphology of T-ANFs was characterized by transmission electron microscopy. The chemical structure of T-ANFs was analyzed via infrared spectroscopy, confirming successful grafting of methyl methacryloyloxy groups onto the surface of aramid nanofibers (ANFs). Real-time infrared spectroscopy was employed to investigate the influence of ANFs and T-ANFs on the photopolymerization kinetics of the EA film. The results revealed that the addition of ANFs and T-ANFs led to a decrease in the photopolymerization rate during the initial stage but had little impact on the final double bond conversion, with all samples exhibiting a conversion rate of over 83%. The incorporation of ANFs improved the tensile strength of the films while significantly reducing their Young's modulus. In contrast, the addition of T-ANFs led to a substantial increase in both tensile stress and Young's modulus of the films. For instance, the tensile strength and Young's modulus of the 0.1 wt% of T-ANF film increased by 52.7% and 41.6%, respectively, compared to the pure EA film. To further study the dispersion morphology and reinforcement mechanism, the cross-sectional morphology of the films was characterized by scanning electron microscopy. [ABSTRACT FROM AUTHOR]

Consumer demands to utilize environmentally friendly packaging have led researchers to develop packaging materials from naturally derived resources. In recent years, plant protein-based films as a replacement for synthetic plastics have attracted the attention of the global food packaging industry due to their biodegradability and unique properties. Biopolymer-based films need a filler to show improved packaging properties. One of the latest strategies introduced to food packaging technology is the production of nanocomposite films which are multiphase materials containing a filler with at least one dimension less than 100 nm. This review provides the recent findings on plant-based protein films as biodegradable materials that can be combined with nanoparticles that are applicable to food packaging. Moreover, it investigates the characterization of nanocomposite plant-based protein films/edible coatings. It also briefly describes the application of plant-based protein nanocomposite films/coating on fruits/vegetables, meat and seafood products, and some other foods. The results indicate that the functional performance, barrier, mechanical, optical, thermal and antimicrobial properties of plant protein-based materials can be extended by incorporating nanomaterials. Recent reports provide a better understanding of how incorporating nanomaterials into plant protein-based biopolymers leads to an increase in the shelf life of food products during storage time. [ABSTRACT FROM AUTHOR]

The nanocomposite films from poly(lactic acid) (PLA) and palmitoylated cellulose nanocrystals (e‐CNCs) were characterized using different techniques. Raman spectra showed the formation of hydrogen bonding interactions between the PLA and the e‐CNCs. The proper amount (1.0 wt%) of the e‐CNCs led to the formation of greater amounts of smaller PLA spherulites and increased the PLA crystallinity in comparison with the neat PLA sample. The scanning and transmission electron microscopy images showed that 1.0 wt% of the e‐CNCs could uniformly be dispersed in the PLA matrix and that the nanocomposite exhibited some elasticity. The dynamic rheological properties showed the formation of interconnected networks in the PLA/e‐CNCs composite at 1.0 wt% of the e‐CNCs. The analysis of the mechanical performance of the ensuing nanocomposite showed a 74% increase in tensile strength, a 62.1% increase in Young's modulus, and a 68.4% increase in the elongation at the break after the incorporation of 1.0 wt% of the e‐CNCs into the PLA. Therefore, the palmitoylated CNCs were highly promising for the simultaneous enhancement in the strength and the toughness of PLA. Highlights: Reinforcement of poly(lactic acid) (PLA) by the palmitoylated CNCs.Simultaneous improvement in the strength and roughness of PLA sample.Entanglement and H‐bond between the palmitoylated CNCs and PLA molecular chain.More and smaller PLA crystals induced by the palmitoylated CNCs. [ABSTRACT FROM AUTHOR]

In this study, electrical properties at alternating current of the nanocomposite films containing silicon and iron inclusions in amorphous SiOx matrix are presented. The composite SiO2(Si)&FexOy(Fe) films were obtained using the ion-plasma co-sputtering of Si and Fe targets in oxygen containing atmosphere (Ar + O2) followed by temperature annealing. It was revealed the predominance of the inductive contribution over the capacitive one in the reactive part of the admittance (impedance) at low frequencies (f < 1 MHz) both after annealing in air and nitrogen atmosphere. The frequency dependences of the admittance after heat treatment in air have the minima that shift to the region of high frequencies with increasing the annealing temperature. In the case of lowfrequency dependence, the phase shift angle passes into the region of positive values, which indicates the predominance of the inductive contribution to the admittance at these frequencies. The dependence of the conductivity real part at the alternating current frequency does not change significantly up to ~20 kHz. Starting from the frequency higher than ~20 KHz and up to ~1 MHz, the exponent in the frequency dependence of the conductivity lies within the limits m ~ 0.49…0.52. [ABSTRACT FROM AUTHOR]

This work employed pulsed laser ablation to produce cellulose acetate butyrate-gold (CAB-Au) nanocomposite films and the evaluation of their structural and thermal characteristics using Raman, X-ray diffraction (XRD), thermogravimetric analysis (TGA), and Differential Scanning Calorimetry (DSC). In the frequency range 0.1–10 MHz, nanocomposite films' dielectric constant, loss, and electric modulus behavior were investigated as a function of temperature. The refractive index, finesse coefficient, Brewster coefficient, critical angles, dielectric function, and color properties of nanocomposite films were examined in the wavelength range 190–800 nm. X-ray diffraction shows a strong Au diffraction signal in all samples, confirming Au NPs. The SEM micrograph shows Au embedded in CAB. The CAB-Au nanocomposites had higher thermal stabilities (Tm) than pure CAB, and the DSC thermograms showed a fluctuating glass transition temperature due to the dynamics of organic-inorganic interactions in the nanocomposite films. Dielectric dispersion is caused by hidden dipolar polarization. The CAB (5 min) sample had the highest ac conductivity as a function of frequency at various temperatures as the Au content in the Au/CAB composite rose. The simplest quantum mechanical tunneling (QMT) model also best explains the ac conduction property. We found a relationship between the nanocomposites' refractive index and the amount (extent of incorporation) of Au in the materials, with laser irradiation time determining the various color constants. Tauc plots reveal a permitted transition with an optical energy gap of 5.1eV for the polymer film and 4.75eV after 10 and 20 min of laser irradiation.

To enhance the various properties of polyvinyl alcohol (PVA), varying concentrations of carboxy-functionalized graphene (CFG) were employed in the preparation of CFG/PVA nanocomposite films. FTIR and XRD analyses revealed that CFG, in contrast to graphene, not only possesses carboxylic acid group but also exhibits higher crystallinity. Mechanical testing indicated a notable superiority of CFG addition over graphene, with optimal mechanical properties such as tensile and yield strengths being achieved at a 3% CFG concentration. Relative to pure PVA, the tensile strength and yield strength of the composite increased by 2.07 and 2.01 times, respectively. XRD analysis showed distinct changes in the crystalline structure of PVA with the addition of CFG, highlighting the influence of CFG on the composite structure. FTIR and XPS analyses confirmed the formation of ester bonds between CFG and PVA, enhancing the overall performance of the material. TGA results also demonstrated that the presence of CFG enhanced the thermal stability of CFG/PVA nanocomposite films. However, analyses using scanning electron microscopy and transmission electron microscopy revealed that a 3% concentration of CFG was uniformly dispersed, whereas a 6% concentration of CFG caused aggregation of the nanofiller, leading to a decrease in performance. The incorporation of CFG significantly enhanced the water vapor and oxygen barrier properties of PVA, with the best performance observed at a 3% CFG concentration. Beyond this concentration, barrier properties were diminished owing to CFG aggregation. The study further demonstrated an increase in electrical conductivity and hydrophobicity of the nanocomposites with the addition of CFG. Antibacterial tests against E. coli showed that CFG/PVA nanocomposites exhibited excellent antibacterial properties, especially at higher CFG concentrations. These findings indicate that CFG/PVA nanocomposites, with an optimized CFG concentration, have significant potential for applications requiring enhanced mechanical strength, barrier properties, and antibacterial capabilities.

Polyethylene oxide‐poly(3,4‐ethylenedioxythiophene) (PEO‐PEDOT) nanocomposite films ‐ incorporated with NiZnFeO4 nanoparticles (NPs) were deposited using a dip‐coating technique. X‐ray diffraction (XRD) analysis revealed peaks at 35.4, 43.2, 54.5, and 56.3° diffraction angles, corresponding to NiZnFeO4NPs diffraction planes of 311, 400, 422, and 511, respectively. The PEO‐PEDOT film exhibited a smooth amorphous nature with a sheet nanostructure behavior. The incorporation of NiZnFeO4NPs NPs into the PEO‐PEDOT nanocomposite films led to an increase in surface roughness and thermal stability. The nanocomposite films also exhibited sheet nanostructure behavior as observed by SEM micrographs. The bandgap energies of the films, as deduced from the Tauc plot, exhibited a monotonic decrease from 3.91 to 3.60 eV as the NiZnFeO4NPs concentration increased from 0 to 8 wt%. A mathematical model was formulated to predict the bandgap energies versus NiZnFeO4NPs concentration. Additionally, the electrical conductivity of the nanocomposite films increased monotonically from 0.46 to 1.30 mS cm−1 as the NiZnFeO4NPs concentration increased from 0 to 8 wt%, as determined by 4‐point probe. The observed correlation between the optical and electrical properties of the nanocomposite films indicates promising prospects for utilizing these materials in optoelectronic devices. [ABSTRACT FROM AUTHOR]

Silver nanoparticles (AgNPs) have received great attention in the fields ranging from antibacterial materials to sensors. Herein, a novel and green strategy based on electrodeposition of polysaccharides (chitosan, carboxylated chitosan, carboxymethyl cellulose, and sodium alginate) is explored to synthesize AgNPs with adjustable particle sizes and their polysaccharide‐based nanocomposite films. These polysaccharides not only serve as the electrodeposited polysaccharide, but also act as the reducing and stabilizing agents for the synthesis of AgNPs. After the electrodeposition of polysaccharides, homogeneous and smooth deposited films (polysaccharide‐based nanocomposite films) have been generated on the anodic electrodes. Spectral analysis and transmission electron microscopy confirm the existence of AgNPs in the nanocomposite films. The as‐fabricated AgNPs from the electrodeposition of four polysaccharides have different particle sizes ranging from 2.19 to 12.89 nm. The difference in the particle size of AgNPs is related to the different reducibility and stabilizing ability of the polysaccharides. This work provides a facile and controllable new electrodeposition strategy for green synthesis of AgNPs with different sizes and their nanocomposite films, which presents great potential in fabricating AgNPs and their nanocomposites with specific particle sizes and particular properties. [ABSTRACT FROM AUTHOR]

Metal oxide nanoparticles (MONPs) (ZnO, TiO2, SiO2, and CuO NPs) were synthesized with an average size of around 50 nm. The synthesized MONPs were incorporated into Poly(methyl methacrylate) (PMMA) matrix deposited on glass substrate led to form PMMA/MONPs nanocomposite films. Fourier-Transform Infrared (FTIR) spectroscopy was employed to investigate the vibrational bands of pure PMMA and the incorporated PMMA/MONPs nanocomposite films. SEM micrographs showed the amorphous morphology of PMMA/MONPs nanocomposite films indicating the excellent dispersion of the MONPs on the surface. PMMA and PMMA/MONPs were exposed to the UV light for a period of 1, 3, and 5 min to investigate the impact on their refractive index (n). The UV-light exposure led to cause an increase in the refractive index of the PMMA in the visible region and decrease in the UV region and the opposite way around in the PMMA/MONPs nanocomposite films. Applying Maxwell–Garnett and Bruggeman's effective medium approximation models to investigate the distribution of the MONPs in the PMMA matrix shows a transfer from continuous aggregated nanoparticles to spherical or ellipsoidal distribution. [ABSTRACT FROM AUTHOR]

Non‐biodegradability and disposal problems are the major challenges associated with synthetic plastic packaging. This review article discusses a new generation of biodegradable active and smart packaging based on porous nanomaterials (PNMs), which maintains the quality and freshness of food products while meeting biodegradability requirements. PNMs have recently gained significant attention in the field of food packaging due to their large surface area, peculiar structures, functional flexibility, and thermal stability. We present for the first time the recently published literature on the incorporation of various PNMs into renewable materials to develop advanced, environmentally friendly, and high‐quality packaging technology. Various emerging packaging technologies are discussed in this review, along with their advantages and disadvantages. Moreover, it provides general information about PNMs, their characterization, and fabrication methods. It also briefly describes the effects of different PNMs on the functionality of biopolymeric films. Furthermore, we examined how smart packaging loaded with PNMs can improve food shelf life and reduce food waste. The results indicate that PNMs play a critical role in improving the antimicrobial, thermal, physicochemical, and mechanical properties of natural packaging materials. These tailor‐made materials can simultaneously extend the shelf life of food while reducing plastic usage and food waste. [ABSTRACT FROM AUTHOR]

ZnO-doped Polyvinyl alcohol/polyvinyl pyrrolidone (PVA/PVP) polymeric films were prepared in this study through an easy and inexpensive solution-casting method. The scope of the study was based on the structural, dielectric, and optical parameters, as well as on the optical limiting effects of the ZnO-doped polymer blend (PB) as nanocomposite films. The X-ray diffraction (XRD) analysis indicated that the synthesized nanocomposites were semicrystalline. The calculated crystalline size of the polymeric semicrystalline peak decreased as ZnO increased or enhanced the blend polymer. Fourier's transformer infrared (FT-IR) study confirmed a substantial dispersion of ZnO nanoparticles in a polymeric PVA/PVP matrix. The optical absorption properties suggested focusing on the surface plasmonic peak (SPR). The refractive index values ranged from 1.718 for the pure PB ZnO0 sample in the Hossam, Ibrahim, and Heba model to 3.036 for the PB ZnO5 film from the Anani model. Nonlinear optical parameters (χ^((3)), and n(2)) were calculated and analyzed for the PB ZnO nanocomposite films under investigation. The maximum value for χ^((1)) was 0.550, while for χ^((3)), its susceptibility value was 155.85 × 10−13 esu, and for the nonlinear refractive index (n^((2)), it was 20.87 × 10−11 esu. A gradual decrease was revealed in the optical limiting sources, as a high content of ZnO was induced in the blend PVA/PVP polymer. Due to their unique properties, these materials can be used in electronic and optoelectronic devices. [ABSTRACT FROM AUTHOR]

Nanocomposite films based on macrocyclic compounds (zinc phthalocyanine (ZnPc) and 5,10,15,20-tetra(4-pyridyl) 21H,23H-porphyrin (TPyP)) and metal oxide nanoparticles (ZnO or CuO) were deposited by matrix-assisted pulsed laser evaporation (MAPLE). 1,4-dioxane was used as a solvent in the preparation of MAPLE targets that favor the deposition of films with a low roughness, which is a key feature for their integration in structures for optoelectronic applications. The influence of the addition of ZnO nanoparticles (~20 nm in size) or CuO nanoparticles (~5 nm in size) in the ZnPc:TPyP mixture and the impact of the added metal oxide amount on the properties of the obtained composite films were evaluated in comparison to a reference layer based only on an organic blend. Thus, in the case of nanocomposite films, the vibrational fingerprints of both organic compounds were identified in the infrared spectra, their specific strong absorption bands were observed in the UV–Vis spectra, and a quenching of the TPyP emission band was visible in the photoluminescence spectra. The morphological analysis evidenced agglomerated particles on the composite film surface, but their presence has no significant impact on the roughness of the MAPLE deposited layers. The current density–voltage (J-V) characteristics of the structures based on the nanocomposite films deposited by MAPLE revealed the critical role played by the layer composition and component ratio, an improvement in the electrical parameters values being achieved only for the films with a certain type and optimum amount of metal oxide nanoparticles. [ABSTRACT FROM AUTHOR]

BACKGROUND: Incorporation of polysaccharide‐based nanofillers is an effective strategy to fabricate bio‐nanocomposite films with preferable mechanical, barrier, and surface hydrophobicity properties compared to pure biopolymer films. The objective of this research is to investigate the influence of starch nanocrystals obtained from native (NSNC) and waxy rice starch (WSNC) on the physical–chemical properties of pullulan‐based nanocomposite films and their preservation performance on fresh beef. RESULTS: Continuous SNCs network structure was observed for pullulan‐10% SNCs nanocomposite films, whereas the percolation network of SNCs was destroyed and became no longer continuous with increasing SNCs concentration up to 20% in pullulan films. Among the tested films, pullulan‐10% SNCs films showed the highest TS values, lowest WVP and OTR values, due to the formation of percolating SNCs network in pullulan matrix. It is noteworthy that the WVP and OTR values of pullulan‐10% WSNC films were significantly lower than that of pullulan‐10% NSNC films, probably due to higher hydrophobicity and crystallinity of WSNC compared with NSNC. Beef pieces coated with pullulan‐SNCs films had higher L* and a* values, lower TVB‐N, TBARS, and TVC values during 7 days' storage at 4 °C compared with samples coated with pullulan films. CONCLUSION: Pullulan‐SNCs nanocomposite films, especially pullulan‐WSNC films, could be potentially used as a coating material for fresh beef due to their desirable oxygen and water barrier properties. © 2022 Society of Chemical Industry. [ABSTRACT FROM AUTHOR]