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Packaging insulation materials with high thermal conductivity and excellent dielectric properties are favorable to meet the high demand and rapid development of third generation power semiconductors. In this study, we propose to improve the thermal conductivity of epoxy resin (EP) by incorporating a three-dimensional boron nitride thermally conductive network. Detailedly, polyurethane foam (PU) was used as a supporter, and boron nitride nanosheets (BNNSs) were loaded onto the PU supporter through chemical bonding (BNNS@PU). After immersing BNNS@PU into the EP resin, EP-based thermally conductive composites were prepared by vacuum-assisted impregnation. Fourier transform infrared spectrometer and scanning electron microscope were used to characterize the chemical bonding and morphological structure of BNNS@PU, respectively. The content of BNNS in BNNS@PU/EP composites was quantitatively analyzed by TGA. The results show that the thermal conductivity of the BNNS@PU/EP composites reaches 0.521 W/m K with an enhancement rate η of 30.89 at an ultra-low BNNS filler content (5.93 wt. %). Additionally, the BNNS@PU/EP composites have excellent dielectric properties with the frequency range from 101 to 106 Hz. This paper provides an interesting idea for developing high thermal conductivity insulating materials used for power semiconductor packaging. [ABSTRACT FROM AUTHOR]

In order to prepare highly heat-resistant packaging insulation materials, in this paper, bismaleimide/epoxy resin (BMI/EP55) composites with different contents of BMI were prepared by melt blending BMI into amino tetrafunctional and phenolic epoxy resin (at a ratio of 5:5). The microstructures and thermal and electrical properties of the composites were tested. The electrostatic potential distribution, energy level distribution, and molecular orbitals of BMI were calculated using Gaussian. The results showed that the carbonyl group in BMI is highly electronegative, implying that the carbonyl group has a strong electron trapping ability. The thermal decomposition temperature of the composites gradually increased with the increase of BMI content, and the 20% BMI/EP55 composites had the highest heat-resistance index, along with a glass transition temperature (Tg) of >250 °C. At different test temperatures, with increase in the BMI content, the conductivity of epoxy resin composites showed a tendency to first decrease and then increase, the breakdown field strength showed a tendency to first increase and then decrease, and the dielectric constant was gradually decreased. Two trap centers were present simultaneously in the composites, where the shallow trap energy level is the deepest in 20% BMI/EP composites and the deep trap energy level is the deepest in 10% BMI/EP55 composites. Correspondingly, the 10% BMI/EP55 composite had a slower charge decay rate, while the 20% BMI/EP55 had a faster charge decay rate. In summary, the BMI/EP55 composites with high heat resistance and insulating properties were prepared in this study, which provided ideas for preparing high-temperature packaging insulating materials. [ABSTRACT FROM AUTHOR]

DNA deformability and differential hydration are crucial determinants of biological processes ranging from genetic material packaging to gene expression; their associative details, however, remain inadequately understood. Herein, we report investigations of the dynamic and thermodynamic responses of the local hydration of a variety of base pair sequences. Leveraging in silico sampling and our in-house analyses, we first report the local conformational propensity of sequences that are either predisposed toward the canonical A- or B-conformations or are restrained to potential transitory pathways. It is observed that the transition from the unrestrained A-form to the B-form leads to lengthwise structural deformation. The insertion of intermittent -(CG)- base pairs in otherwise homogeneous -(AT)- sequences bears dynamical consequences for the vicinal hydration layer. Calculation of the excess (pair) entropy suggests substantially higher values of hydration water surrounding A conformations over the B- conformations. Applying the Rosenfeld approximation, we project that the diffusivity of water molecules proximal to canonical B conformation is least for the minor groove of the canonical B-conformation. We determine that structure, composition, and conformation specific groove dimension together influence the local hydration characteristics and, therefore, are expected to be important determinants of biological processes. [ABSTRACT FROM AUTHOR]

Fluorescent chitin nanofibers (FChN), as a new type of promising fluorescent nanomaterials, exhibit the characteristics of low toxicity, biocompatibility, biodegradability, sustainability, and high crystallinity and mechanical modulus. However, there is a tradeoff between fluorescence and nanosizing efficiency in processing and conversion of chitin into FChN, because amino groups in chitin are easily converted into fluorescent groups during the first modification process; therefore, FChN are usually prepared with low efficiency via nanosizing first and then modification. Herein, FChN with excellent fluorescence properties were efficiently prepared via a modification-first strategy assisted by a mild and facile click chemistry of partially deacetylated chitins (DEChs). Enough amino groups (22%–30%) were retained in fluorescent DEChs by precise adjustment of reaction activity of amino–yne/hydroxy–yne click chemistry of DEChs, which was the key for the successful preparation of FChN with high efficiency of almost 98%. The first click modification process was mild and had no negative effect on the morphology of FChN, which was similar to that of unmodified chitin nanofibers. In addition, FChN dispersion showed excellent fluorescence and could be used as fluorescent inks for anti-counterfeit printing; FChN films not only showed high fluorescent stability in water, ethanol, DMF, DMSO and 8 wt% NaOH aqueous solution for 30 days, but also exhibited high stress of 200.12 ± 1.70 MPa, excellent UV-blocking properties and controlled biodegradability. This facile and efficient method provides a more sustainable strategy for preparation of functional chitin nanofibers which has high potential for application to anti-counterfeiting, biosensing and smart packaging materials. [ABSTRACT FROM AUTHOR]

Fully biodegradable packaging materials are demanded to resolve the issue of plastic pollution. However, the fresh food storage performance of biodegradable materials is generally much lower than that of plastics due to their high permeability, microbial friendliness, and limited stretchability and transparency. Here a biodegradable packaging material is reported with high fresh food storage performance based on an oil‐infused bacterial cellulose (OBC) porous film. The oil infusion significantly improved cellulose's food‐keeping performance by reducing its gas permeability, increasing its stretchability and transparency, and enabling the active release of green vapor‐phase preservative molecules, while maintaining its intrinsically high degradability. Strawberries stored in a container with the OBC lid at 23 °C after 5 days exhibited a moldy rate of 0%, in contrast to the 100% moldy rate of those stored by poly(ethylene). Enhanced storage performance is also obtained on tomatoes, pork, and shrimp. The OBC film is naturally degraded after being buried in wet soil at 30 °C for 9 days, identical to the degradation rate of bacterial cellulose. The liquid seal strategy broadly applies to different celluloses, providing a general option for developing cellulose‐based biodegradable packaging materials. [ABSTRACT FROM AUTHOR]

The biodegradable materials for the packaging sector have attracted much attention as they can effectively reduce the reliance on fossil fuel products. The introduction of two‐dimensional layered fillers is readily available for packaging materials to minimize costs while enhancing performance. However, few studies have investigated the molecular structure changes of OMMT to further modulate the comprehensive performance of polyhydroxy butyrate (PHB) materials. To fill this gap, we innovatively modified the surfactant's structure to regulate the embedding and dispersion of montmorillonite (OMMT) and interfacial bonding with the substrate, thus further examining the material's antibacterial and degrading properties and discussing mechanisms for the first time. The prepared C18M7@PHB materials present enhanced tensile strength (180%) and high thermal stability, excellent antimicrobial properties compared to the unmodified one. Both the water vapor and oxygen permeabilities of composites have decreased by 87% and 55%, respectively. Moreover, it is found that the composites exhibit various degradation cycles mainly depending on active agent chain length. This work lays a solid foundation for multifunctional packaging materials based on fillers with two‐dimensional layered structures. Highlights: Determining the ideal film's bulk ratio and active agent structure.Optimizing the film's excellent tensile strength and antimicrobial properties.Significantly blocking the infiltration of water vapor and oxygen.Identifying the film's filler's degradation behavior and barrier mechanism. [ABSTRACT FROM AUTHOR]

Thermally conductive polymeric composites with low dielectric constant are highly promising for the packaging materials in the field of modern communication. Therefore, the synergistic improvement of low dielectric constant and high thermal conductivity has become a current research hotspot. In this work, we propose a one‐step alkylation of boron nitride nanosheet (BNNS) with ultrasonic stratification using 1‐hexanol, and then hot press the films to make Alkyl‐BNNSs orient in the fluorinated polyimide (f‐PI). The resulting Alkyl‐BNNS/f‐PI composite successfully realizes the synergistic improvement of thermal property and dielectric properties, exhibiting a high heat conductivity coefficient of 2.36 Wm−1 K−1 with a filler content of 4.99 wt.%. Moreover, the permittivity and dielectric loss of the film are as low as 1.76 and 0.0065 at 1 MHz, respectively. This work provides a facile strategy for breaking the bottleneck of making polyimide composites simultaneously with high thermal conduction and low dielectric performance. Highlights: The composite exhibits a high heat‐conducting coefficient of 2.36 Wm−1 K−1.Ultra‐low dielectric constant of 1.76 was achieved by the modification of film.Excellent breakdown resistance and flexibility were endowed with the composites. [ABSTRACT FROM AUTHOR]

Food safety and quality are major concerns in the food industry. Despite numerous studies, polyethylene remains one of the most used materials for packaging due to industry reluctance to invest in new technologies and equipment. Therefore, modifications to the current materials are easier to implement than adopting whole new solutions. Antibacterial activity can be induced in low-density polyethylene films only by adding antimicrobial agents. ZnO nanoparticles are well known for their strong antimicrobial activity, coupled with low toxicity and UV shielding capability. These characteristics recommend ZnO for the food industry. By incorporating such safe and dependable antimicrobial agents in the polyethylene matrix, we have obtained composite films able to inhibit microorganisms' growth that can be used as packaging materials. Here we report the obtaining of highly homogenous composite films with up to 5% ZnO by a melt mixing process at 150 °C for 10 min. The composite films present good transparency in the visible domain, permitting consumers to visualize the food, but have good UV barrier properties. The composite films exhibit good antimicrobial and antibiofilm activity from the lowest ZnO composition (1%), against both Gram-positive and Gram-negative bacterial strains. The homogenous dispersion of ZnO nanoparticles into the polyethylene matrix was assessed by Fourier transform infrared microscopy and scanning electron microscopy. The optimal mechanical barrier properties were obtained for composition with 3% ZnO. The thermal analysis indicates that the addition of ZnO nanoparticles has increased thermal stability by more than 100 °C. The UV-Vis spectra indicate a low transmittance in the UV domain, lower than 5%, making the films suitable for blocking photo-oxidation processes. The obtained films proved to be efficient packaging films, successfully preserving plum (Rome) tomatoes for up to 14 days. [ABSTRACT FROM AUTHOR]

Polymeric thin films based on polylactide with an addition of poly(ethylene glycol) as a plasticizer and flavonoids in the form of quercetin and berberine were subjected to tests that were particularly relevant from the point of view of contact with food. A comparative analysis of the effect of individual flavonoids on the antioxidative properties of tested films and blueberry storage was carried out. The influence of active compounds on the water vapor permeability, as well as UV protection, of the obtained materials was investigated. Also, the specific migration of individual flavonoids from obtained materials to food simulants in the form of acetic acid and ethyl alcohol was determined. The crucial point of this study is the storage of blueberries. The obtained results indicate that the selection of packaging, containing individual active compounds, depends on the purpose and requirements that the packaging must meet for particular types of food. [ABSTRACT FROM AUTHOR]

The in-line control of curing during the molding process significantly improves product quality and ensures the reliability of packaging materials with the required thermo-mechanical and adhesion properties. The choice of the morphological and thermo-mechanical properties of the molded material, and the accuracy of their determination through carefully selected thermo-analytical methods, play a crucial role in the qualitative prediction of trends in packaging product properties as process parameters are varied. This work aimed to verify the quality of the models and their validation using a highly filled molding resin with an identical chemical composition but 10 wt% difference in silica particles (SPs). Morphological and mechanical material properties were determined by dielectric analysis (DEA), differential scanning calorimetry (DSC), warpage analysis and dynamic mechanical analysis (DMA). The effects of temperature and injection speed on the morphological properties were analyzed through the design of experiments (DoE) and illustrated by response surface plots. A comprehensive approach to monitor the evolution of ionic viscosity (IV), residual enthalpy (dHrest), glass transition temperature (Tg), and storage modulus (E) as a function of the transfer-mold process parameters and post-mold-cure (PMC) conditions of the material was established. The reliability of Tg estimation was tested using two methods: warpage analysis and DMA. The noticeable deterioration in the quality of the analytical signal for highly filled materials at high cure rates is discussed. Controlling the temperature by increasing the injection speed leads to the formation of a polymer network with a lower Tg and an increased storage modulus, indicating a lower density and a more heterogeneous structure due to the high heating rate and shear heating effect. [ABSTRACT FROM AUTHOR]

Petroleum-based plastics have been widely used as packaging materials because of their low-cost availability and good mechanical properties. However, the use of plastics has become restricted as they are highly resistant to biodegradation, causing environmental problems. This work aimed to produce and characterize emulsified pullulan films incorporating geraniol for application as food packaging materials with potential to substitute the conventional plastics. When geraniol was incorporated in the films, they showed antimicrobial activity against Enterococcus faecalis ATCC 29212 (inhibition zone diameter = 15.19 ± 0.66 mm) and Pseudomonas aeruginosa ATCC 27853 (inhibition zone diameter = 10.99 ± 1.82 mm). Furthermore, scanning electron microscopy showed the inhibition of Enterococcus faecalis ATCC 29212 biofilms when they were directly formed on the emulsified pullulan films incorporating geraniol. The produced films also demonstrated high transparency (> 90%) and hydrophilic surfaces (water contact angle < 90°). This work demonstrated the viability of using geraniol to produce pullulan active films as new food packaging materials. [ABSTRACT FROM AUTHOR]

This study proposed an innovative approach to the development of sustainable and biodegradable food packaging materials by incorporating inexpensive nano-silica (SiO2NPs) in designed hydrogel (CSG) film employing biodegradable polymers: synthetic polymer polyvinyl alcohol (PVA), natural polymer - carboxymethyl cellulose (CMC) and protein-based bio-polymer –gelatine, and a commercial crosslinker, tetraethoxysilane (TEOS) through a conventional air-dry casting technique. The CSG hydrogel blends were modified with varying amounts of SiO2NPs (0.05g, 0.1g, 0.15g and 0.2g) and compared with the blend without SiO2NPs to determine the effect of SiO2NPs loading through various characterisation techniques and applications including antioxidant and antimicrobial activity. Comprehensive characterizations of the CSG films revealed that CSG 0.1 (containing 0.1g SiO2NPs) exhibited the most favourable functional properties, low crystallinity, high flexibility, suitable pore size, thermal stability, adequate tensile strength, elongation at the breaking point and maximum stability by swelling and diffusion test. The addition of SiO2NPs consistently enhanced thermal and mechanical stability in all CSG films. Further, these CSG films were implemented for antioxidant test and antimicrobial activity against gram-positive Bacillus cereus and gram-negative Escherichia coli. SiO2NPs integration significantly elevated the antioxidant capacity in all films, with CSG 0.1 showing ⁓7% improvement. The antimicrobial activity of SiO2NPs-modified CSG films was also notable, with CSG 0.1 effectively inhibiting B. cereus by 1.2cm zone and E. coli by 0.5cm zone. A soil burial test was performed to pattern the biodegradability of CSG hydrogels. Therefore, the outstanding improvements in the intrinsic properties of CSG films, owing to SiO2NPs modification, positioned these CSG hydrogels as promising candidates for advanced food packaging materials in various industries. [ABSTRACT FROM AUTHOR]

The detection of nitrosamine impurities, particularly small dialkyl types, which are frequently known to be potent mutagenic carcinogens, in some Sartan group active pharmaceutical ingredients (APIs) and finished drug products caused global regulatory organizations to have concerns. Accordingly, Registration Holders/Applicants, API manufacturers, and their raw material suppliers are required to check the presence of nitrosamines in their products and carry out risk assessments using the quality risk management principles specified in the ICH Q9 guide. In this context, a new LC-MS/MS method has been developed and validated for the simultaneous determination of NDMA, NDEA, NMBA, NDIPA, NEIPA, NDBA, and MeNP nitrosamine compounds in API and finished products as well as in primary packaging materials, one of the risk sources. This validated method was applied to check the nitrosamine content may occur from canister, blister, printed aluminum foil, nasal spray, and eye drop packaging materials as part of the Extractables & Leachables studies arising from interactions between the product and the primary packaging. For the determination and quality control of nitrosamines in sartan group pharmaceutical products and packaging materials, the developed LC-MS/MS analytical method offers highly reliable, fast, high accuracy, good sensitivity and simultaneous detection even at low concentrations. • A new LC-MS/MS method was developed and validated for the detection of nitrosamine impurities in different combined finished products containing sartan group and alu-foil packaging. • Different packaging components were studied within the scope of the Extractables&Leachables study to evaluate the possibility of leaching not only from tablet blisters but also from different pharmaceutical packaging components and ink printed labels. • Validation parameters and acceptance criteria were determined in accordance with USP 〈736〉 mass spectrometry monograph and ICH Q2 (R2) guide. • Packaging components (such as canister, blister, printed aluminum foil, nasal spray, and eye drop packaging materials) were checked in accordance with risk assessment studies carried out in line with the ICH Q9 guide. [ABSTRACT FROM AUTHOR]

Using cellulosic micro/nanofibrils (MFC/NFC) in developing films for coatings and packaging has aroused industrial interest to replace plastic. This study proposes functionalizing packaging films composed of hybrid suspensions of 80 % titica vine (Heteropsis flexuosa) and 20 % Pinus to improve their mechanical properties. The MFC/NFC were produced by mechanical fibrillation and adding proportions of 1, 2.5, and 5 % of nanolignin, vegetal tannin, and synthetic termite saliva. Both suspensions had concentrations of 1 % (w/w). The MFC/NFC were evaluated for energy consumption, microstructural, and stability, while the films were for physical, optical, barrier, and mechanical properties. Films with nanolignin 2.5 % obtained lower WVP and degradation in water, with greater hydrophobicity and puncture strength. The treatment with tannin 1 % obtained higher density and lower porosity, while termite saliva 1 % presented higher tensile strength at around 53.1 MPa. The additives improved the quality index of the MFC/NFC (>51.1 points). It is concluded that adding different binders can help expand the use of MFC/NFC. New studies are essential to seek pre-treatments or alternative fibrillation methods to increase their application and efficiency for fiber cell wall fibrillation, in addition to the need for a deeper analytical understanding of the interactions of additives with cellulose. [ABSTRACT FROM AUTHOR]

Food packaging is an essential line to defend against the intrusion of undesirable external factors to protect food. The antibacterial edible films are considered as promising food packaging due to their biodegradability, environmental friendliness, and safety. In this paper, recent research progress on antimicrobial edible films based on polysaccharides, proteins, and lipids is reviewed. It is worth noting that polysaccharides and proteins are the main substrates of antimicrobial edible films, while lipids are mainly plasticizers and carriers of active substances in composite films. For example, second-generation liposomes have been investigated as promising carriers for antimicrobial substances or other bioactive substances due to their excellent stability. Moreover, recent advances and future trends of antimicrobial edible films are then analyzed. Linking antimicrobial edible film materials to delivery systems for stable loading of bioactive substances is a promising future direction, such as nanoemulsion and microencapsulation technologies. In addition, a smart and active packaging that allows consumers to directly determine the freshness of food products without unwrapping the package has come into the limelight. Currently, pH-sensitive films and smart fluorescent "on–off" sensors for humidity have been investigated as smart and active packaging materials for monitoring the freshness of food products, which can be vigorously explored in the future. [ABSTRACT FROM AUTHOR]

Facing increasing social, environmental, and economic pressure to substitute non-renewable fossil resources with renewable ones, hemicellulose has received attention as a substrate for the production of high-value products such as packaging materials because of its non-toxicity, abundance, and biodegradability. Hemicelluloses in the cell wall are naturally substituted with acetyl groups, and the degree and pattern of acetylation vary among plant species, tissue and cell types, and plant maturity. Hemicellulose acetylation influences features such as the flexural properties of wood, polysaccharide interactions, plant growth, and stress resistance. However, hemicellulose is deacetylated during its separation from other biomass polymers, mainly via alkaline solubilization. Therefore, when industrial applications require a certain degree of acetylation, chemical acetylation is necessary, which occurs through an esterification reaction that links acetyl groups to hemicellulose, catalyzed or not. Acetylation may enhance some features of hemicellulose-based packaging materials, such as mechanical strength, processability, thermal stability, hydrophobicity, and oxygen and water vapor permeability. This review provides an update on the latest advances in plant polysaccharide acetylation, including the acetylation mechanism in the plant cell wall as well as the influence of such esterification on plant properties and wood industrial application. Recent developments and progress in hemicellulose chemical acetylation strategies have been summarized, disclosing the advantages and disadvantages of different solvents and catalysts applied and acetylation evaluation methods. [ABSTRACT FROM AUTHOR]

Environmental friendly biocomposites are urgently needed to mitigate the pollution caused by huge consumption of petroleum-based polymers. Renewable carrageenan and polylactic acid (PLA) natural polymers have the potential to replace petroleum-origin polymers. Nevertheless, the carrageenan and PLA themselves inherit poor tensile strength, hydrophobicity and stability. The aim of this study is to underpin the mechanism of synthesis of carrageenan-PLA biocomposite using van't Hoff plot, 1HNMR and density functional theorem simulation. Strong hydrogen bonding was found at 1.88 Å between O atom (carrageenan) and H atom (PLA) and was validated in 1HNMR shifting at 5.3 ppm corresponding to –OH group from PLA. The interaction established in the biocomposite mixed at 50 °C leads to a stronger tensile strength of 75.37 MPa, higher hydrophobicity and thermal stability with highest activation energy of 45.39 kJ/mol. The biocomposite produced from renewable carrageenan-PLA material would be a future replacement for nondegradable plastic as a food packaging material. [ABSTRACT FROM AUTHOR]

The advancement of sustainable packaging technologies is crucial for environmental conservation and enhancing food shelf life. We advance sustainable packaging by developing cassava starch sheets functionalized with silver nanoparticles (AgNPs) via plasma-deposited 2-methyl-2-oxazoline thin film. This innovative method requires less precursors and generates no liquid waste, presenting a significant leap in eco-friendly packaging solutions. Uniquely, it deviates from traditional nanoparticle incorporation methods by emphasising surface functionalization over bulk integration, leveraging plasma polymerization for environmentally friendly and efficient AgNP immobilisation. This surface-centric approach offers distinct advantages in active packaging by enhancing the initial antimicrobial interaction at the packaging's surface. Surface morphology, characterised by SEM–EDX, and chemical composition, verified by XPS, indicated successful AgNP immobilisation after 5 and 25 h, albeit with some aggregation at prolonged immobilisation time. UV–Vis spectroscopy results confirmed the successful immobilisation of AgNPs and suggested enhanced light barrier properties of the treated sheets. AFM measurements revealed alterations in surface roughness post-treatment, correlating with changes in hydrophilicity and potentially impacting the moisture barrier properties of the packaging. The treated bioplastics showed improved mechanical properties, indicated by tensile strength and elongation at break. Antimicrobial testing revealed substantial efficacy against Gram-positive and Gram-negative bacteria, but not against fungi. All bioplastic samples demonstrated non-toxicity to fibroblast cells, irrespective of the treatments applied. This work paves the way for future developments targeted at improving the efficacy and scalability of plasma-nanoengineered bioplastics. [ABSTRACT FROM AUTHOR]

Coffee husk (CH) and brewery spent grain (BSG) fibers are sustainable industrial residues that consist of cellulose. The present study aimed at the extraction of cellulose from CH and BSG fibers and to study the effect of alkali-hydrogen peroxide (5% NaOH–7% H2O2) treatment during the extraction by characterizing the extracted cellulose. Characterization of cellulose particles, such as crystallinity, functional groups, thermal properties, and morphology, was conducted by performing X-ray diffraction (XRD), Fourier transform infrared spectroscopy (FTIR), thermogravimetric analyzer (TGA), and scanning electron microscopy (SEM), respectively. The finding shows that the maximum cellulose yields obtained from CH and BSG fibers are 37.3% and 26.5%, respectively. From the XRD results, the cellulose obtained from CH fiber (C-CH) and from BSG fiber (C-BSG) showed diffractive peaks with the highest intensity of approximately 1,003 and 1,236 counted at 2θ = 22°, respectively. A reduction in the absorption of peaks was observed on the FTIR spectrum for both C-BSG and C-CH samples at different wavelengths. SEM demonstrated that the surface roughness of the celluloses was enhanced. TGA showed that the maximum temperature decomposition observed for both C-CH and C-BSG is 360°C and 380°C, respectively. Generally, in this study, alkali-hydrogen peroxide (5% NaOH–7% H2O2) treatment was effectively used for the treatment of BSG and CH fibers for the extraction and surface modification of cellulose particles. The extracted cellulose in the present study can be used as an alternative to conventional cellulose for the manufacturing of biocomposite materials, preparation of particle boards and furniture, and production of food packaging materials. [ABSTRACT FROM AUTHOR]

Background: Nanotechnology has gained rapid popularity in many fields, such as food science. The labile bioactive is enclosed in a shield that protects it from harmful environmental factors. It also allows for targeted delivery to specific areas. Bioactive compounds in foods are slowly degraded or can change due to external or internal factors such as oxidation. Innovative technologies and novel edible packaging materials can be used to reduce bioavailability. One promising technology for overcoming the problems above is encapsulation. Nanostructure systems enhances a number of properties, including resistance to degradation and improvements of physicochemical functions like solubility, stability, and bioavailability, among others as the nanosize increases surface area and, consequently, activity. A recently emerged nanoencapsulation technologies, including electro spraying, nano-fluidics, complex coacervation, electrospinning, polymerization, etc. have been briefly discussed. Different bioactive molecules can be nano encapsulated by absorbing, incorporating, chemically interacting, or dispersing substances into nanocarriers. There have also been other characterization techniques and different physico chemical parameters investigated to evaluate the characteristics of encapsulated bioactives. The current article highlights numerous bioactive substances utilized for nanoencapsulation using cutting-edge methods. Short conclusion: This review examines how different encapsulating bioactive materials can improve encapsulating films or coatings. The advent of nanotechnology has opened up a wide range of possibilities for the development, design, and formulation of innovative pharmaceuticals. The food and pharmaceutical industry can focus its attention on products that have added value through the various enhancements offered by nanoencapsulation. [ABSTRACT FROM AUTHOR]

This work demonstrates that the packaging material commonly called “bubble wraps” (Aeroplast) can be leveraged to serve as a probe to visible sunlight exposure. This probe relies on a newly developed layered metal selenide photocatalyst with the general formula (DMAH)2xMnxSn3–xSe6 (DMSe‐1) (x = 1.3–1.7; DMAH+ = dimethylammonium), featuring a narrow bandgap of 0.76 eV, in addition to an indicator dye and a reducing agent. The photochemically sensitive probe is introduced into the air‐filled compartments of bubble wraps and undergoes photocatalytic degradation, resulting in a chromatic response to sunlight exposure. The probe's sensitivity to variable irradiation doses can be adjusted by varying the amount of the photocatalyst. The color intensity correlates with the absorbed irradiation dose, allowing for qualitative assessment by the naked eye or quantitative measurement using the RGB color system. The results obtained from the new probe agree with those obtained from standard sunlight pyranometers (r = 0.98), with an average error of <15%. This suggests that beyond their use as protective coatings, bubble wraps can be successfully repurposed as visible light sensors. Furthermore, this study describes the initial use of metal chalcogenides as visible light probes, potentially paving the way for the development of innovative light‐sensitive materials. [ABSTRACT FROM AUTHOR]

Biopolymers are important due to their exceptional functional and barrier properties and also their non-toxicity and eco-friendly nature for various food, biomedical, and pharmaceutical applications. However, biopolymers usually need reinforcement strategies to address their poor mechanical, thermal, and physical properties as well as processability aspects. Several natural nanoparticles have been proposed as reinforcing agents for biopolymeric food packaging materials. Among them, zein nanoparticles (ZNPs) have attracted a lot of interest, being an environmentally friendly material. The purpose of the present review paper is to provide a comprehensive overview of the ZNPs-loaded nanocomposites for food packaging applications, starting from the synthesis, characteristics and properties of ZNPs, to the physicochemical properties of the ZNPs-loaded nanocomposites, in terms of morphology, permeability, solubility, optical features, hydrophobic/hydrophilic behavior, structural characteristics, thermal features, and mechanical attributes. Finally, at the end of this review, some considerations about the safety issues and gastrointestinal fate of ZNPs, as well as the use of ZNPs-based nanocomposites as food packaging, are reported, taking into account that, despite the enormous benefits, nanotechnology also presents some risks associated to the use of nanometric materials. [ABSTRACT FROM AUTHOR]

This research presents a new approach to facilely fabricating a multifunctional film using polyvinyl alcohol (PVA) as the base material. The film is modified chemically to incorporate various desirable properties such as high transparency, UV‐shielding, antibacterial activity, and fluorescence. The fabrication process of this film is straightforward and efficient. The modified film showed exceptional UV‐blocking capability, effectively blocking 100% of UV radiation. It also exhibits strong antibacterial properties. Additionally, the film emitted bright blue fluorescence, which can be useful in various optical and sensing applications. Despite the chemical modification, the film retained the excellent properties of PVA, including high transparency (90%) at 550 nm and good mechanical strength. Furthermore, it demonstrated remarkable stability even under harsh conditions such as exposure to long‐term UV radiation, extreme temperatures (−40 or 120 °C), or immersion in different solvents. Overall, this work showcases a promising strategy to develop versatile, structurally stable, transparent, and flexible polymer films with multiple functionalities. These films have potential applications in various fields that require protection, such as packaging materials, biomedical devices, and optical components. [ABSTRACT FROM AUTHOR]

This review article provides a thorough overview of barrier coating materials that have been used in food packaging with a focus on biodegradable (bio-based or petroleum-based) materials, such as lipids, proteins, polysaccharides, agriculture waste and polyesters. The goal is to provide an opportunity to acknowledge progress made in this field, focusing on modifications made to coatings. These modifications aim to address the shortcomings of biodegradable substrates (either plastic or paper) and improve their performance, enabling them to compete with traditional petroleum-based food packaging materials. This includes their barrier against water vapor and oxygen, mechanical and surface characteristics (sealability and adhesion), as well as antimicrobial properties. The barrier of most biodegradable polymers underperforms in comparison with petroleum-based non-biodegradable polymers, which possess either high water vapor barrier or high oxygen barrier. Coating technology is a promising solution particularly in barrier improvement of biodegradable polymers. Currently, there are only metallized, or inorganic nanosheet coatings available for biodegradable films that meet food packaging requirements. There are some challenges in this field, for example, being able to retain the coating's biodegradability despite applied modifications to improve it's performance, the large-scale fabrication of biodegradable coatings, the coating's delamination and heat-sealability during service time, and the migration of the coating into the packaged food. Moreover, green chemistry and its sustainability needs in biodegradable polymeric coatings are also discussed regarding new ideas and possible directions for widespread application of coatings in food packaging. This is the first review that specifically summarizes biodegradable coatings on plastic and paper substrates with a focus on coating modifications to improve the performance of the base substrate to meet the required properties for food packaging applications. [ABSTRACT FROM AUTHOR]

This article discusses the use of propolis, a natural substance produced by bees, for preserving meat and cheese. The study explores different methods of incorporating propolis into packaging materials or directly onto the food to extend shelf life and inhibit the growth of bacteria and fungi. The research highlights the antimicrobial and antioxidant properties of propolis and its potential as a natural preservative. Various studies are cited to support the effectiveness of propolis in preserving different types of meat and cheese. [Extracted from the article]

Developing a moisture-stable structural material with high toughness is essential for improving the stability of packaging and building materials. Wood is a pervasive structural material with naturally good mechanical properties. However, insufficient moisture stability and toughness compromises its safety and structural requirements. Herein, we constructed a moisture-stable wood veneer with high toughness by assembling the choline chloride-ethanolamine delignified wood with alkali lignin, followed by hot-pressing to densify the material. Lignin can be assembled into the microchannel of the delignified wood as a filler and binder for reducing molecular transportation and increasing internal bonding. The enhanced tensile strength (582.0 MPa) and strain (3.6%) are accompanied by a significant increase in the toughness to 11.1 MJ/m3, which is 37 times higher than that of natural wood. The excellent mechanical property can be preserved to a large extent after retaining in tropic moisture conditions (38 °C, 90% RH) with retention of 66.2% and 60.8% for tensile strength and toughness, respectively. A stable water contact angle on the surface and limited water adsorption of reconstructed wood indicate a lowered water infiltration velocity, suggesting highly improved moisture stability as needed for structural materials. [ABSTRACT FROM AUTHOR]

Presently, the food industry continues to be major contributor of plastic waste across the globe. The food industry is in great demand of sustainable food packaging material due to increase environmental and health consciousness. Biobased polymers which are degradable promise to be a key solution. Use of nanotechnological advancements in biopolymers provide a wide range of additional benefit and makes them a suitable packaging material. The benefits include barrier to oxygen permeability, moisture permeability, crystalline structure, other barrier properties, morphology, thermal stability, optical properties, mechanical properties, improving shelf life of the packaged food and antimicrobial characteristics. Polymeric materials (matrix) have been infused with nanofillers such as silicates, carbon, cellulose and starch nanoparticles. This review aims to focus on new and effectual polymeric materials for food packaging that are technologically advanced with nanotechnology as a solution to the challenges faced by food industry with regard to the product safety and materials performance. [ABSTRACT FROM AUTHOR]

This paper presents comparative data on the structural, thermal, and mechanical characteristics, the work of adhesion as well as the anti-mold activity of composites based on PVA and Ag–Cu structures. A one-stage method for obtaining polymer composites with Ag–Cu using underwater pulsed plasma is considered. Two- and three-stage chemical methods for obtaining Ag–Cu structures with/without using the stabilizer (chitosan and polyvinylpyrrolidone) are also compared. The incorporation of the filler into the polymer matrix is confirmed by XRD patterns and FTIR spectroscopy data. The results of thermal and mechanical tests have shown that the synthesis method and the nature of the stabilizer allow the creation of more platy composites. The introduction of Ag–Cu fillers increases the resistance to UV radiation and changes the work of adhesion. The method of production, the concentration of the filler, and the nature of the stabilizer affect the anti-mold activity of the composites. Analysis of obtained results, PVA/Ag–Cu composites can be considered promising food packaging materials. [ABSTRACT FROM AUTHOR]

Tea is the most consumed beverage worldwide and has many health effects. Although there are many different types of tea, black tea and green tea comprise 98% of total tea production in the world. Tea waste production consists of withering, crushing, fermentation, drying and finally packaging processes. All of the waste generated during this production line is called tea waste. Tea production results in a significant amount of waste that cannot be effectively used for value creation. This waste contains many different components including protein, fiber, caffeine, and polyphenols. Due to its rich composition, it can be revalorized for different purposes. In this study, the general composition and bioactive compounds of tea waste were reviewed. Despite the fact that there have been few studies on the bioactivity of tea waste, those studies have also been discussed. The extraction techniques that are used to separate the compounds in the waste are also covered. It has been indicated that these valuable compounds, which can be separated from tea wastes by extraction methods, have the potential to be used for different purposes, such as biogas production, functional foods, food additives, silages, soluble packaging materials, and adsorbents. Although there are some studies on the revalorization of tea waste, new studies on the extraction of bioactive compounds are necessary to improve its utilization potential. [ABSTRACT FROM AUTHOR]

The improper disposal of plastics is a growing concern due to increasing global environmental problems such as the rise of CO2 emissions, diminishing petroleum sources, and pollution, which necessitates the research and development of biodegradable materials as an alternative to conventional packaging materials. The purpose of this research was to analyse the properties of biodegradable polymer blends of thermoplastic potato starch (TPS) and polylactide, (PLA) without and with the addition of citric acid (CA) as a potential compatibilizer and plasticizer. The prepared blends were subjected to a comprehensive physicochemical characterization, which included: FTIR-ATR spectroscopy, morphological analysis by scanning electron microscopy (SEM), determination of thermal and mechanical properties by differential scanning calorimetry (DSC), water vapour permeability (WVP), as well as biodegradation testing in soil. The obtained results indicate an improvement in adhesion between the TPS and PLA phases due to the addition of citric acid, better homogeneity of the structure, and greater compatibility of the polymer blends, leading to better thermal, mechanical and barrier properties of the studied biodegradable TPS/PLA polymer blends. After conducting the comprehensive research outlined in this paper, it has been determined that the addition of 5 wt.% of citric acid serves as an effective compatibilizer and plasticizer. This supplementation achieves an optimal equilibrium across thermal, mechanical, morphological, and barrier properties, while also promoting material sustainability through biodegradation. In conclusion, it can be stated that the use of thermoplastic starch in TPS/PLA blends accelerates the biodegradation of PLA as a slowly biodegradable polymer. While the addition of citric acid offers significant advantages for TPS/PLA blends, further research is needed to optimize the formulation and processing parameters to achieve the desired balance between mechanical strength, thermal and barrier properties and biodegradability. [ABSTRACT FROM AUTHOR]

Polymer/polymer nanocomposites based on high-density polyethylene (HDPE) and biocompatible polyvinyl alcohol (PVA) were prepared by tensile drawing of HDPE in the PVA solutions via environmental crazing. The mechanism of this phenomenon was described. The HDPE/PVA nanocomposites were studied by the methods of scanning electron microscopy, atomic force microscopy, gravimetry, tensile tests, and their composition, properties, and performance were characterized. The content of PVA in the HDPE/PVA nanocomposites (up to 22 wt.%) was controlled by the tensile strain of HDPE and concentration of PVA in the solution. Depending on the content of PVA, the wettability of the HDPE/PVA nanocomposite (hydrophilic-lipophilic balance) could be varied in a broad interval from 45 to 98°. The modification of HDPE by the biocompatible PVA offers a beneficial avenue for practical applications of the HDPE/PVA composites as biomedical materials, packaging and protective materials, modern textile articles, breathable materials, membranes and sorbents, etc. [ABSTRACT FROM AUTHOR]

Purpose: The purpose of this study is to enhance the functional properties of Hessian fabric through resin finishing. Hessian bags made of lignocellulosic jute fiber are commonly used to pack, store and transport agro-commodities, including horticultural crops such as rice, potato, onion and wheat. However, because of high water affinity, these bags undergo degradation in properties due to moisture release by the stored commodities themselves. Exposure to natural elements, e.g. rain and dew, also causes moisture absorption in hessian bags. Once the bag gets moistened, degradation of jute bags starts due to microbial attack, leading to loss in tensile strength and change in extensibility, leading to ultimate breakage in warp and weft directions of the fabric. Design/methodology/approach: To overcome the degradation in the functional properties of hessian fabric due to exposure to moisture and microbial attack, the application of semi-synthetic polymeric materials was carried out. Findings: Tenacity, bursting strength, puncture resistance, tear strength and breaking load, as well as life cycle of resin-treated jute fabric was found to be better than control jute. Originality/value: To the best of the authors' knowledge, no recent reports of resin finishing on jute (hessian) fabric with semi-synthetic resins are presently available, other than coating with rubber. [ABSTRACT FROM AUTHOR]

This study focuses on the modification of starch using cold plasma (CP) for 0, 30, 60, and 90 seconds. The prepared films are characterized (i.e., thickness, water vapor permeability, intrinsic viscosity, solubility in water, and moisture absorption). The thickness, water vapor permeability (WVP), intrinsic viscosity, solubility in water (SW), moisture absorption (MA), and roughness of the modified starch films increases with longer plasma‐processing time (PPT). Conversely, the contact angle and density of the films decreases. However, there are no significant changes observed in the moisture content and UV–Vis spectrum of the cold plasma‐irradiated starch (CPS) films. The CP treatment has some effects on the mechanical properties of the films, such as elongation at break and tensile energy to break, but the tensile strength remains unaffected by PPT. Additionally, CP has a significant impact on the visual properties of CPS films, with increased lightness and white index with longer PPT. Most of the observed characteristics are attributed to physical changes in the starch structure caused by etching. Overall, CP is considered a green, and easy for modifying starch‐based packaging materials. However, it is not an effective method for reducing the sensitivity of the films to moisture at the applied PPT. [ABSTRACT FROM AUTHOR]

Superabsorbent bio-aerogels were developed from TEMPO-oxidized cellulose nanofibers (isolated from vegetable lignocellulosic residues) and two different commercial chitosan reactants (low and high molecular weight) by polyelectrolyte complex formation at room temperature. The materials were designed with the aim to provide useful, bio-based, and environmentally friendly food packaging supplies able to successfully replace those currently used that are made of synthetic and non-biodegradable polymers. Three different thickness values were considered, and two different aging times were employed, thus leading to twelve different bio-aerogel samples. Remarkably, no crosslink agents nor organic solvents were used. The bio-aerogel's components were strongly interacting through hydrogen bonding and electrostatic interactions, leading to highly porous and stable materials able to absorb high amounts of water and soybean oil. Then, the specific tests to visualize the material's potential use as food absorbent pads showed the following: (i) they were able to absorb simulated food exudates under a specific pressure in higher quantities (≈4000%) than some commercial pads (≈1600%); (ii) the materials have low to moderate antibacterial activities exposing better reduction effectiveness for Listeria monocytogenes than for Salmonella typhimurium; and (iii) the antioxidant properties were in general low. In the light of all the results achieved, the bio-aerogels prepared from H-CH with an aging time of 24 h and whose thickness was around 2.1 mm (H-10g-24) were selected as the most appropriate for the desired application. [ABSTRACT FROM AUTHOR]

In this study, for the first time, double-layer films based on furcellaran and gelatin were obtained, in which the 1st layer of furcellaran was enriched with various plant extracts. The aim of this work was to improve the composition of the developed innovative packaging material by using two layers of biopolymer complexes and analysing the composites to determine the effect of different model plant extracts on the physicochemical properties of the double-layered materials. Furthermore, the hypothesis that positron annihilation lifetime spectroscopy (PALS) could be correlated with gas barrier properties was verified. The addition of plant extracts significantly influenced the physicochemical parameters of the obtained double-layered materials. The lowest solubility was noted in films with the addition of garlic extract (58.40%) and black pepper extract (59.26%) which also had the lowest water content (8.88%). The film with garlic extract also had the lowest oxygen transfer rate (OTR) value after 6 months of storage which is consistent with PALS. The presented data suggest the possibility of correlating PALS results with the gas barrier properties. Tests carried out using this method will facilitate the selection of new potential ingredients when designing packaging materials based on biopolymers, thus, making it possible to obtain new-generation matrices. [ABSTRACT FROM AUTHOR]

The present study evaluated, through physical and physiological tests, the seed quality of a landrace fava bean variety in different packaging materials and storage periods, aiming to guarantee the conservation of their quality in seed banks and facilities. The methodology used was the one recommended by the Rules for Seed Analysis (RAS - Brasil, 2009) and minimum descriptors for Phaseolus lunatus L. The data were subjected to analysis of variance by the F-test at 5% signififance to verify the presence of significant interactions and the individual effects of each treatment. The test of multiple comparison of means was performed by the Tukey test at 5% significance between common treatments. The Dunnett test was used at 5% significance to compare the control means with the means of the treatments. R egression analysis was performed to study the effect of storage on the variables evaluated. All analyses were performed using the R software. From the results, it can be concluded that the storage of fava bean seeds is viable in small rural properties in impermeable packaging materials and aluminized polyethylene bags. The germination and vigor of the seeds analyzed in this study decreased throughout the storage period regardless of the type of packaging used. It is not recommended to store fava bean seeds in permeable paper packaging as they have the lowest quality indices (germination and vigor) at the end of the storage period. [ABSTRACT FROM AUTHOR]

Phthalate esters (PAEs) are a group of chemicals used to improve the flexibility and durability of plastics. The chemical properties and the resistance to high temperatures promote their degradation and release into the environment. Food and beverages can be contaminated by PAEs through the migration from packaging material because they are not covalently bound to plastic and also via different kinds of environmental sources or during processing. For instance, alcoholic drinks in plastic containers are a particular risk, since the ethanol contained provides a good solubility for PAEs. According to its role as an endocrine disruptor compound and its adverse effects on the liver, kidney, and reproductive and respiratory systems, the International Agency on Research Cancer (IARC) classified di-(2-ethylhexyl) phthalate (DEHP) as a possible human carcinogen. For this reason, to control human exposure to PAEs, many countries prohibited their use in food as non-food substances. For example, in Europe, the Commission Regulation (EU) 2018/2005 restricts the use of DEHP, dibutyl phthalate (DBP), benzyl butyl phthalate (BBP), and diisobutyl phthalate (DiBP) to a concentration equal to or below 0.1 by weight in plasticizers in articles used by consumers or in indoor areas. There are reports from the US Food and Drug Administration (FDA) that some beverages (and food as well), particularly fruit juices, contain high levels of phthalates. In some cases, the deliberate adulteration of soft drinks with phthalate esters has been reported. This paper would like to show the difficulties of performing PAE analysis in beverage matrices, in particular alcoholic beverages, as well as the main solutions provided for quality control in the industrial branches. [ABSTRACT FROM AUTHOR]

This comprehensive review addresses the vital environmental concerns posed by conventional petroleum-based plastics, particularly in the context of the packaging industry's extensive reliance on these materials. As nearly 99% of plastics originate from non-renewable petrochemical sources and their non-biodegradable nature leads to widespread waste accumulation and harmful emissions upon disposal, the need for sustainable alternatives has become paramount. This paper explores the escalating environmental and health repercussions linked to traditional plastics, underscored by global initiatives, including restrictions on single-use plastics, aimed at mitigating these challenges. In response, the paper highlights the growing interest in environmental friendly biopolymers, which can be sourced from renewable biological materials or synthesized from biopolymers such as starch, casein etc. The classification of biopolymers into three primary categories; natural biopolymers, microbial fermentation-derived biopolymers, and polymerized monomers from biomass is comprehensively examined. Furthermore, the paper emphasizes the pivotal role of biopolymer properties, such as barrier characteristics, mechanical strength, heat resistance, biodegradability, flexibility, food contact safety, and cost-effectiveness, in determining their suitability for packaging applications. It also stresses the importance of conducting life cycle assessment (LCA) to holistically evaluate the environmental sustainability of biopolymers. This review highlights the potential of integrating biopolymers into packaging materials as a promising avenue to reduce the adverse environmental impact of traditional plastic production. These biodegradable materials, with their diverse properties and renewability, offer a sustainable approach to mitigating plastic waste and lowering greenhouse gas emissions. However, further research, development, and collaborative efforts are essential to optimize biopolymer performance, reduce production costs, and facilitate broader adoption. Embracing biodegradable polymers represents a commitment to resource efficiency, waste reduction, and environmental preservation, fostering a more sustainable and ecofriendly future. [ABSTRACT FROM AUTHOR]

Synthetic plastic is the most anxious polymer in packing industry due to its non-biodegradability and biogeomagnification in the ecosystem. In light of the growing worldwide concern over synthetic polymers, natural and semi-synthetic biodegradable packaging materials with microbicide properties are receiving more attention in the food industry. The current research emphasises on the idea to convert a waste aquatic weed in to an advantageous eco-friendly substitute to a harmful biomagnifying food packing material. Water weed Eichhornia crassipes was used for the formation of hybrid films with nanocellulose and nanoclay coupled with green synthesised zinc oxide nanoparticles (NPs) by C. fistula fruit extract. Physicochemical properties of the starch-based binary nanocomposite (BNC) as well as ternary nanocomposite (TNC) were confirmed by TGA, DSC, SEM, EDX, FTIR and XRD analyses. The mechanical properties of both BNC and TNC were evaluated for its tensile strength, Young's modulus and elongation break analysis. Further, the established ternary nanocomposite film with 2% ZnO NPs showed better surface morphology compared to the control binary films. Microbial efficacy studies revealed that the synthesised films are microbicidal in nature against foodborne pathogens Escherichia coli, Botrytis cinerea and Sclerotium rolfsii. The overall study accentuates that the green-based nanocomposites are eco-friendly, economically feasible and act as an effective route to overcome foodborne pathogens conferring them to be an alternative to petrochemical-based product. [ABSTRACT FROM AUTHOR]

Composite polymer materials featured superior thermal conductivity, flame retardancy, and electromagnetic shielding performance are increasingly in demand due to the rapid development of highly miniaturized, portable, and flexible electronic devices. Herein, a facile and green ball milling shear method is utilized for generating MXene@Boron nitride (MXene@BN). The multi‐functional fillers (MXene@BN) are constructed and incorporated into polydimethylsiloxane (PDMS) to prepare a multifunctional composite (PDMS/MXene@BN) for achieving improved electromagnetic interference (EMI) shielding performance and thermal conductivity as well as flame retardancy simultaneously. When the PDMS/MXene@BN composite has a MXene@BN loading of 2.4 wt.%, it exhibits a high thermal conductivity of 0.59 W m−1K−1, which is 210% higher than that of the pure PDMS matrix. This is attributed to its unique chestnut‐like double‐layer structure. With a smoke production rate (SPR) of 0.04 m2 s−1 and total smoke production (TSP) of 3.51 m2, PDMS/MXene@BN 2.4 composite exhibits superb smoke suppression properties. These SPR and TSP values are 63.20% and 63.50% lower than the corresponding values of pure PDMS. Moreover, the EMI SE of the PDMS/MXene@BN 2.4 can reach 26.3 dB at 8.5 GHz. The work reported herein provides valuable insight into developing composites with multiple functions, which show strong potential for application in advanced packaging materials. [ABSTRACT FROM AUTHOR]

With the development of microelectronics products with high density and high power, it is urgent to improve the electrical and thermal conductivity of electronic paste to achieve the new requirements of packaging materials. In this work, a new synthesis method of Ag-MWCNTs was designed: Firstly, carboxylated MWCNTs and stannous chloride were used as raw materials to prepare high-loading-rate Sn-MWCNT composite material to ensure the high loading rate of metal on the MWCNT surface. Then, Ag-MWCNT composite material was prepared by the chemical displacement method to solve the problem of the low loading rate of silver nanoparticles on the MWCNT surface. On the basis of this innovation, we analyzed and compared the electrical, thermal, and mechanical properties of Ag-MWCNT composite electronic paste. Compared with the electronic paste without adding Ag-MWCNTs, the resistivity was reduced by 77%, the thermal conductivity was increased by 66%, and the shear strength was increased by 15%. Therefore, the addition of Ag-MWCNTs effectively improves the electrical, thermal, and mechanical properties of the paste, making it a promising and competitive choice for new packaging materials in the future. [ABSTRACT FROM AUTHOR]

Nowadays, increased food safety and decreased food waste are two of the major global interests. Self-healable active packaging materials are an attractive option to achieve such targets. This property is critical for the hygiene and the consumption appropriateness of the food. Polylactic acid is a very promising polymeric matrix that potentially could replace the widely used low-density polyethylene due to its biobased origin and its easy biodegradable nature. The main drawback of this polymeric matrix is its brittle, fragile nature. On the other hand, tetraethyl citrate is a biobased approved food additive which became an attractive option as a plasticizer for industries seeking alternative materials to replace the traditional petrochemically derived compounds. A novel biobased film exhibiting self-healing behavior suitable for food-active packaging was developed during this study. Polylactic acid's brittleness was reduced drastically by incorporating tetraethyl citrate, and a random cut on the original self-repairing film was fully healed after 120 s. The optimum concentration of tetraethyl citrate in the polylactic acid was around 15% v/w with a water/oxygen barrier close to the relevant of polylactic acid and low migration. According to the EC50 parameter, the antioxidant activity was 300% higher than the relevant of pure polylactic acid, while according to the thiobarbituric acid and heme iron parameters, the film resisted lipid oxidation and deterioration. Finally, the total viable count parameter indicates the strong antimicrobial activity of this sample. [ABSTRACT FROM AUTHOR]

Biodegradable composite films comprising of poly(butylene adipate-co-terephthalate) (PBAT), polylactic acid (PLA), and tetrapod-zinc oxide (T-ZnO) whisker were prepared by a melt-extrusion and blow molding process. The effect of the incorporation of the T-ZnO whisker (1 to 7 wt.%) in the PBAT/PLA blend film was studied systematically. The composite films with an optimal T-ZnO whisker concentration of 3 wt.% exhibited the highest mechanical (tensile strength ~32 MPa), rheological (complex viscosity~1200 Pa.s at 1 rad/s angular frequency), and gas barrier (oxygen permeability~20 cc/m2·day) properties, whereas the composite films with 7 wt.% T-ZnO whiskers exhibited the highest antibacterial properties. The developed composite films can find potential application as antibacterial food packaging materials. [ABSTRACT FROM AUTHOR]

Plastic containers, commonly produced from non-biodegradable petroleum-based plastics such as polyethylene (PE), polypropylene (PP), and polyethylene terephthalate (PET), raise significant environmental concerns due to their persistence. The disposal of agricultural waste, specifically rice straw (RS), through burning, further compounds these environmental issues. In response, this study explores the integration of polylactic acid (PLA), a biodegradable material, with RS using a twin-screw extruder and injection process, resulting in the creation of a biodegradable packaging material. The inclusion of RS led to a decrease in the melt flow rate, thermal stability, and tensile strength, while concurrently enhancing the hydrophilic properties of the composite polymers. Additionally, the incorporation of maleic anhydride (MA) contributed to a reduction in the water absorption rate. The optimized formulation underwent migration testing and met the standards for food packaging products. Furthermore, no MA migration was detected from the composite. This approach not only provides a practical solution for the disposal of RS, but also serves as an environmentally-friendly alternative to conventional synthetic plastic waste. [ABSTRACT FROM AUTHOR]

This study presents an analysis of films which consist of two layers; one layer is PVDF as the matrix, along with fillers BaTiO3 (BT), and the second is one bacterial nanocellulose (BNC) filled with Fe3O4. The mass fraction of BT in PVDF was 5%, and the samples were differentiated based on the duration of the mechanical activation of BT. This innovative PVDF laminate polymer with environmentally friendly fillers aligns with the concept of circular usage, resulting in a reduction in plastic content and potential improvement of the piezoelectric properties of the entire composite. This work presents new, multifunctional "green" packaging materials that potentially could be a good alternative to specific popular materials used for this purpose. The synthesis of the films was carried out using the hot press method. Tensile tests, water vapor permeability examination, and structural analyses using SEM-EDS and FTIR have been conducted. The sample PVDF/BT20/BNC/Fe3O4 exhibited the best barrier properties (impermeability to water vapor), while the highest tensile strength and toughness were exhibited by the PVDF/BT5/BNC/Fe3O4 sample. [ABSTRACT FROM AUTHOR]

Nanotechnology is being used to create innovative food packaging systems that can inhibit the oxidation of foods, thereby improving their quality, safety, and shelf life. These nano-enabled antioxidant packaging materials may therefore increase the healthiness and sustainability of the food supply chain. Recent progress in the application of nanotechnology to create antioxidant packaging materials is reviewed in this paper. The utilization of nanoparticles, nanofibers, nanocrystals, and nanoemulsions to incorporate antioxidants into these packaging materials is highlighted. The application of nano-enabled antioxidant packaging materials to preserve meat, seafood, fruit, vegetable, and other foods is then discussed. Finally, future directions and challenges in the development of this kind of active packaging material are highlighted to stimulate new areas of future research. Nanotechnology has already been used to create antioxidant packaging materials that inhibit oxidative deterioration reactions in foods, thereby prolonging their shelf life and reducing food waste. However, the safety, cost, efficacy, and scale-up of this technology still needs to be established before it will be commercially viable for many applications. [ABSTRACT FROM AUTHOR]