Water Vapor Transmission Rate Research Articles

Development of Novel Frontsheets With Protective Coatings to Increase the Durability and Reliability of Glass‐Free Lightweight PV Modules

ABSTRACTIn this work, novel PET‐based frontsheet materials with UV‐cured coatings were developed and investigated. UV‐curing urethane acrylates were selected as innovative, fluorine‐free coating systems. Polyurethane coatings exhibit excellent UV resistance, chemical and moisture resistance and, thus, high durability in outdoor applications. A homogeneous application without coating defects such as bubbles, voids or detachments was achieved. Material tests with cross‐cut tests showed no separation from the PET substrate. The water vapor transmission rates and the physical (optical and thermal) and chemical properties of the novel polymeric frontsheets were measured and compared with uncoated reference systems and products already on the market. The aging‐related changes after irradiation and humid heat storage were investigated and described in detail. Based on this comprehensive study, the newly developed frontsheets can be considered a suitable alternative to polymeric frontsheets with fluorine‐containing top layers.

Physicochemical Characterization and Kinetics Study of Polymer Carriers with Vitamin C for Controlled Release Applications

This study focuses on the selection and evaluation of a kinetic model for the release of vitamin C from different delivery systems, including microcapsules, hydrogels, and a hybrid system combining both. The microcapsules were synthesized from a 2% sodium alginate solution and with vitamin C incorporated in selected formulations. Hydrogels were obtained through photopolymerization using poly(ethylene glycol) diacrylate and polyvinyl alcohol, with and without the addition of vitamin C. The hybrid system incorporated the vitamin C-containing microcapsules within the hydrogel matrix. Physicochemical properties, such as density, porosity, and water vapor transmission rate (WVTR), were evaluated. Kinetic studies of vitamin C release were conducted under dynamic and static conditions, and the experimental data were fitted to six different kinetic models: zero-order, first-order, second-order, Higuchi, Korsmeyer–Peppas, and Hixson–Crowell. The Higuchi and Korsmeyer–Peppas models provided the best fit for most systems, indicating that the release is predominantly controlled by diffusion and, in dynamic conditions, swelling of the matrix. The hybrid system, while exhibiting slower release than the microcapsules and hydrogel alone, demonstrated more controlled and sustained release, which is advantageous for applications requiring prolonged action.

Physical and biological characteristics of electrospun poly (vinyl alcohol) and reduced graphene oxide nanofibrous structure

The fabrication of graphene-based nanocomposites has been a topic of increasing interest due to graphene’s exceptional physical properties and the ability to enhance the properties of various polymeric materials. Evaluating the biocompatibility of these nanocomposites is crucial to ensure their safe and effective use in biomedical applications. This study characterized and assessed the biocompatibility of previously fabricated electrospun polyvinyl alcohol (PVA)/reduced graphene oxide rGO fibrous structures by conducting a comprehensive assessment of their physical and biological characteristics. Contact angle measurements revealed that adding rGO to electrospun PVA fibers enhanced the surface wettability, improving the fibrous structure’s PBS absorption capacity and degradation behavior. Including the rGO content resulted in a higher water vapor transmission rate, reaching ∼48 g/m2·day for PVA + 0.5 wt.% rGO and ∼45 g/m2·day for PVA + 1.0 wt.% rGO, compared to ∼40 g/m2·day for electrospun PVA fibers. Cell culture studies, including MTT assay, alkaline phosphatase (ALP) activity analysis, alizarin red staining, fluorescence microscopy, and SEM analyses, demonstrated that electrospun PVA + 1.0 wt.% rGO nanocomposites exhibited superior cell viability, proliferation, and growth compared to other samples, due to the improved physical properties of the PVA + 1.0 wt.% rGO fibrous structure.

Innovative biopolymers composite based thin film for wound healing applications

Efficient wound and burn healing is crucial for minimising complications, preventing infections, and enhancing overall well-being, necessitating the development of innovative strategies. This study aimed to formulate a novel thin film combining chitosan, carboxymethyl cellulose, tannic acid, and beeswax for improved wound healing applications. Several formulations, incorporating chitosan, carboxymethyl cellulose, tannic acid, and beeswax in various percentages, were utilized to deposit thin films via the solvent evaporation technique, Mechanical properties, morphology, antioxidant activity, antibacterial efficacy, and wound healing potential were evaluated. The optimized thin film (M4), composed of 2% chitosan, 2% carboxymethyl cellulose, and 1% tannic acid, along with 0.2% glycerol and 0.2% tween80, exhibited a thickness of 39.0 ± 1.14 μm and a tensile strength of 0.275 ± 0.003 MPa. It demonstrated a swelling degree of 283.0 ± 2.0% and a drug release capacity of 89.4% within 24 h. The film also showed a low contact angle of 40.5° and a water vapour transmission rate of 1912.25 ± 13.10 g m−2 0.24 h−1. FT-IR spectroscopy indicated that chitosan and carboxymethyl cellulose were cross-linked through amide linkages, with tannic acid occupying the interstitial spaces and hydrogen bonding stabilizing the structure. Microscopy of M4 revealed a uniform morphology. The film exhibited strong antioxidant activity of (95.17 ± 0.02%) and antibacterial efficiency (80.8%) against S. aureus. In a rabbit model, the film significantly enhanced burn and excision wound recovery, with 90.0 ± 3.3% healing for burns and 88.85 ± 1.7% for infected wounds by day 7. Complete skin regeneration was observed within 10–12 days. The M4 thin film demonstrated exceptional mechanical properties and bioactivity, offering protection against pathogens and promoting efficient wound healing. These findings suggest its potential for further investigation in treating various infections and its role in developing novel therapeutic interventions.

Reversible Photo-Responsive Hydrophobic Coating Synthesized from Lignin-Derivable Molecules on Nanocellulose Films for Packaging Applications.

Paper-based packaging can offer a sustainable replacement for plastics. However, paper provides a poor barrier to water, oxygen and moisture. This study presents a novel renewable lignocellulosic composite made from a hydrophobic photo-reversible coating deposited onto a cellulose nanofiber film that has improved barrier properties and can be reprocessed. Diglycerol and lignin-derivable aldehyde were reacted to form a tetra-functional monomer with photo-responsive unsaturated double bonds that can be converted to covalent cyclobutane rings to create reversibly crosslinkable network upon UV-irradiation. The photo-responsive compound was applied as a thin coating of thickness 2.7±0.4 μm over cellulose nanofiber (CNF) films of thickness 80±19 μm. The surface of the coated films became hydrophobic with a contact angle (CA) of 93.1±1.7° and displayed a low water vapour transmission rate (WVTR) of 16±2 g/m2/day vs. 30.7±1.5° CA and 81±11 g/m2/day WVTR for uncoated CNF films. The coated film is also oleophobic, an attractive feature for food packaging applications. The reversible photo-reaction enables the crosslinked covalent network to be broken down to unsaturated double bonds once exposed to a higher-energy UV irradiation, allowing reprocessing and recycling. The novel coating was developed using a sustainable green synthesis method (process simple E factor 0.9).

Water Vapor-Impermeable AlON/HfOx Bilayer Films Deposited by Hybrid High-Power Impulse Magnetron Sputtering/Radio-Frequency Magnetron Sputtering Processes

Water vapor-impermeable AlON/HfOx bilayer films were constructed through a hybrid high-power impulse magnetron sputtering (HiPIMS) and radio-frequency magnetron sputtering process (RFMS), applied as an encapsulation of flexible electronics such as organic photovoltaics. The deposition of monolithic and amorphous AlON films through HiPIMS was investigated by varying the duty cycles from 5% to 20%. At an accelerated test condition, 60 °C, and 90% relative humidity, a 100 nm thick monolithic AlON film prepared using a duty cycle of 20% exhibited a low water vapor transmission rate (WVTR) of 0.0903 g m−2 day−1 after testing for 336 h. Furthermore, after introducing a nanocrystalline HfOx film through RFMS, a 214 nm thick AlON/HfOx bilayer film reached the lowest WVTR of 0.0126 g m−2 day−1.

OPTIMIZATION OF PROCESS PARAMETERS FOR ENHANCING THE SKIN PERMEATION EFFICIENCY OF NISOLDIPINE LOADED ULTRA DEFORMABLE VESICLES IN TRANSDERMAL PATCHES

Objective: The study aimed to address the limitations of oral delivery and enhance the bioavailability of nisoldipine (NSD) through the development of transferosomal transdermal patches containing ultra-deformable transferosomes. Methods: NSD, known for its low oral bioavailability and adverse effects, was encapsulated in transferosomes using a thin film hydration method. 17 formulations were made using Box Behnken Design, varying Dipalmitoylphosphatidylcholine (DPPC), span-80, and stirring speed, and were evaluated for vesicle size, Polydispersity Index (PDI), and Entrapment Efficiency (EE%). The optimal formulation, selected based on these parameters, was combined into Transdermal Patches (TPs). The patches underwent extensive testing for physicochemical properties, in vitro and ex-vivo permeation, and skin irritancy. Results: The results showed transferosomes with Vesicle Sizes (VS) ranging from 124±2.25 to 400±1.55 nm and EE% from 52.88±0.23 to 90.01±1.58%, with Zeta Potentials (ZP) between-48 to-20 mV. The patch thickness (0.66±0.02 mm) and weight per square inch (382.1±1.69 mg) showed consistent manufacturing, while the Water Vapor Transmission Rate (WVT) (1.54±0.01g/m²/24h), low moisture content (1.07±0.01%), and regulated moisture absorption (3.78±0.01%) maintained formulation stability. In vitro and ex-vivo permeation indicated superior drug permeation for transferosomal patches (NP) compared to plain nisoldipine patches (NP-N), with permeation directly proportional to PEG-400 concentration. Additionally, the transferosomal patches were found to be free from skin irritation. Conclusion: The optimized Niosoldipine transferosomal patch (NP-3) composition displays good folding endurance (FE) 97.67±0.47, required for transdermal systems, and successfully allows drug permeation (DP) at 86.39±2.64% in a short timescale. Hence, the study concludes that transferosomal patches of NSD offer a promising approach for effective transdermal delivery, potentially improving hypertension management by providing a controlled and prolonged drug release.

Development of Ultrathin, Breathable, Waterproof, and Durable Nanonet‐Supported Ionogel Sensors for Electrophysiological Monitoring

AbstractIonogel has gained attention as a promising material for flexible electronic skin (e‐skin), due to its exceptional conductivity, compositional stability, and biocompatibility. Nevertheless, establishing a seamless interface between ionogel and human skin remains a significant challenge. This study presents the design and fabrication of a nanonet‐supported ionogel with a thickness of ≈16 µm, marking it the thinnest ionogel reported to date. This ultrathin ionogel exhibits remarkable toughness (5.51 MJ m−3), a broad strain range (0–375%), and impressive fatigue resistance, enduring over 3000 cycles. Additionally, it offers excellent water resistance and a high water vapor transmission rate (WVTR), supporting perspiration and enhancing skin breathability. Moreover, the ultrathin ionogel has potential as a carrier in transdermal drug delivery systems (TDDS), highlighting its suitability for biomedical applications. Wearable devices incorporating this ultrathin ionogel facilitate continuous, sensitive, and highly accurate monitoring of physiological signals, positioning it as a promising material for future flexible e‐skin material.

Synthesis and evaluation of self‐healing polyvinyl alcohol‐tannic acid membranes for skin bio‐applications

AbstractAutonomic self‐healing films have shown limited mechanical strength, hindering their application as biomaterials, particularly in skin bioengineering. To address this challenge, we developed polyvinyl alcohol (PVA)‐tannic acid (TA)‐based membranes with improved self‐healing properties and strong mechanical performance. Using a blade coating method and freeze–thaw cycles (−10°C for 1 h, followed by room temperature thawing), the synthesized membranes demonstrated a tensile strength of 8.8 MPa before healing and 7.6 MPa after healing, achieving an 88% healing efficiency. Membrane thickness showed a slight reduction from 465 to 432 μm posthealing. After 3000 bending cycles at a 1 cm radius, the membranes maintained flexibility with no significant changes in water vapor transmission rate (WVTR) (7.66 g/m2·day) or oxygen transmission rate (OTR) (0.13 cm3/m2·day·bar). These results underscore the membranes' suitability for dynamic skin environments, combining robust mechanical properties with excellent self‐healing capabilities. The PVA‐TA membranes present a promising solution for advanced skin bioengineering applications.

PET nano-woven luminescent fibers for efficient air filtration and fluorescence indication of particulate matter

Inhalable particulate matter poses significant health risks, and current air filtration materials often struggle with efficiently capturing particles smaller than 300 nm and providing real-time feedback on filtration performance. We present the synthesis and characterization of polyethylene terephthalate (PET) nano-woven luminescent fibers (PNWLFs), created through a positive and negative dual high-voltage electrospinning method. The PNWLFs feature a unique nano-woven structure composed of backbone fibers (200–1000 nm) and nanofibers (20–160 nm), which endow them with remarkable mechanical strength, maintaining a breaking force of 117.5 cN and structural integrity under a 138 mm water column. The fibers exhibit excellent breathability and waterproof performance, with a water vapor transmission rate of 4.69 kg/m2/day. More importantly, the PNWLFs demonstrate exceptional air filtration capabilities, achieving filtration efficiencies of 99.77 % for PM5.0, 99.76 % for PM2.5, 99.72 % for PM1.0, 99.53 % for PM0.5, and 99.40 % for PM0.3, with minimal pressure drop of 106 Pa. Additionally, these fibers possess a unique fluorescence-indicating function: the fluorescence intensity decreases in response to increasing particulate matter concentration and the number of filtration cycles, allowing for intuitive visual monitoring of filter performance and particulate levels. These attributes underscore the significant potential of PNWLFs synthesized by this work for advanced air filtration applications and effective air quality monitoring.

Development of κ-carrageenan-based transparent and absorbent biodegradable films for wound dressing applications

Wound healing remains a critical challenge in healthcare, requiring advanced wound dressings with superior properties like transparency, absorbency, and biocompatibility. However, gaps exist in the use of marine-derived biopolymers for sustainable dressings. This study addresses this gap by combining κ-carrageenan (KC) with polyvinyl pyrrolidone (PVP) to develop transparent and absorbent biodegradable films through solvent casting and lyophilization techniques. Lyophilized films exhibited superior absorbency (9.17 g/cm2) and moisture management, with a water vapour transmission rate of 3990.67 g/m2/24 h, while solvent-cast films showed 78 % transmittance, enabling wound visualization. Mechanical testing revealed high tensile strength (31.5 MPa) and folding endurance (410 folds), ensuring durability. In vitro bactericidal assays confirmed efficacy against MRSA and E. coli, and in vivo tests on Wistar rats showed complete wound healing within 16 days with 91.1 % closure, outperforming untreated controls (76.7 %). This is the first study to explore lyophilized KC-PVP films for wound dressing applications, demonstrating potential for drug release, absorbency, and biodegradability. The innovative combination of biopolymers and fabrication techniques offers a sustainable, high-performance solution for wound care.

Fish oil-containing edible films with active film incorporated with extract of Psidium guajava leaves: preparation and characterization of double-layered edible film.

The utilization of zein and gum arabic has grown in an attempt to formulate wall materials based on protein-polysaccharide complexes. This mixture provides a versatile delivery system for hydrophilic (guava leaf extract, GLE) or lipophilic (fish oil, FO) bioactive compounds, and it can be used as an edible film-forming polymer. This study was undertaken to characterize FO-containing edible films that were double-layered with a film containing GLE. Modified zein and gum arabic solutions (MG complex) were mixed at a ratio of 1:1.5 (v/v), adjusted to pH 5, added with glycerol (20% of the complex) and FO (5% of the complex), and finally adjusted to pH 5. This was prepared as the bottom/lower layer. The upper/active layer was prepared by mixing MG complex, glycerol, and GLE (1, 3, and 5% w/v of the complex). The total phenolic and flavonoid contents in GLE were 15.81 mg GAE/g extract and 6.99 mg QE/g extract, respectively. The IC50 of the DPPH radical scavenging activity of GLE was 26.86 ppm with antibacterial activity against Bacillus subtilis and Escherichia coli of 9.83 and 12.55 mm. The total plate counts of double-layered films containing GLE were retained below 3 log CFU/g during 28-day storage. The peroxide values of these films were dimmed for no more than 9.08 meq/kg sample on day 28 of storage. Thickness (872.00-971.67 μm), water vapor transmission rate (12.99-17.04 g/m 2/day), tensile strength (1.56-2.02 kPa), elongation at break (61.53-75.41%), glass transition (52.74-57.50°C), melting peak (131.59-142.35°C), inhibition against B. subtilis (33.67-40.58 mm), and inhibition against E. coli (2.05-9.04 mm) were obtained by double-layered films. GLE can be successfully incorporated into the active layer of a double-layer film to improve its characteristics while significantly slowing down the microbial contamination and oxidation rate. MG complex and FO can also contribute to the performance of the edible film.

Performance analysis of biodegradable composite using polyvinyl alcohol and pomegranate peel powder for sustainable dry packaging applications

This study focuses on the fabrication of a biodegradable dry packaging material for fruits, vegetables, and flowers, with an emphasis on affordability for street vendors. Approximately 55% of waste originates from packaging materials. To address this issue, a biodegradable Polyvinyl alcohol/Pomegranate peel powder (PVA/PPP) composite film was fabricated. The PVA, a water-soluble synthetic biodegradable polymer, served as the matrix, while PPP, an agro-waste product, was used as the filler. The PVA/PPP films were characterized through optical microscopy, FTIR, XRD, TGA, DSC, moisture absorption analysis, water vapour transmission rate (WVTR), water vapour permeability (WVP), and oxygen permeability testing. The inclusion of PPP enhanced the film’s properties via increasing moisture absorption by 85%, reducing PVA crystallinity index from 33.2 to 17.5%, percentage crystallinity reduced from 73.90 to 0.57%, lowering WVTR from 0.063 to 0.042 g/h.m2, low oxygen permeability and improving thermal stability up to 423 °C. Additionally, the pH of PPP (4.5) contributed to microbial resistance. The fabricated PVA/PPP films were fully biodegradable and produced via green synthesis without any hazardous chemicals. The use of PPP as a filler not only improved film performance but also reduced environmental hazard, demonstrating the material’s suitability for sustainable packaging applications.

Improved mechanical, thermal, and barrier properties of halloysite nanotubes and nanocellulose incorporated PVA-PEO films: For food packaging applications

This work presents a novel polyvinyl alcohol (PVA)-polyethylene oxide (PEO) nanocomposite with halloysite nanotube (HNT)-nanocellulose (NC) hybrid filler to tailor the mechanical, thermal, and barrier properties. PVA-PEO/ HNT-NC nanocomposites are characterized using various analytical techniques such as FTIR, XRD, TGA, DSC, and SEM. The study evaluated the impact of hybrid filler on water vapor transmission rate (WVTR), moisture retention capacity (MRC), peroxide value (POV), and mechanical properties. The simultaneous application of 3 wt% HNT and 5 wt% NC resulted in a 20 % increase in tensile strength and approximately two-fold increase in Young's modulus, with a maximum degradation temperature increase of 22° C and 16° C in the second and third stages, respectively. Compared to the pure blend, the nanocomposite exhibited a 67 % (26.7 ± 0.6 mEq/kg) improvement in oxygen barrier performance, while maintaining a low WVTR and good MRC, demonstrating their suitability for packaging applications.

Phase-Changeable Metafabric Enables Dynamic Subambient Humidity and Thermal Regulation.

A promising approach to prevent heat- and cold-related illnesses is the integration of zero-energy input control technology into personal thermal management (PTM) systems while reducing energy consumption. However, achieving optimal wearing comfort while maintaining subambient metabolic temperatures using thermally regulating materials without an energy supply remains challenging. In this study, we provide a simple and reliable methodology to produce a phase-changeable metafabric made of thermoplastic polyurethane and phase change capsule (PCC) particles with high moisture permeability and thermal comfort. This approach skillfully incorporates spray-formed PCC particles into a three-dimensional nanofibrous aggregate, forming a stable self-entangled network structure in a single step through simultaneous humidity-assisted electrospraying and electrospinning processes. Additionally, the metafabric demonstrates prominent water resistance and superhydrophobicity, which are attributed to the integration of PCC particles and nanofibers, resulting in the formation of a microporous/nanoporous structure resembling the surface of a lotus leaf. As a result, the phase-changeable metafabric shows an active and passive thermal control performance, with a water vapor transmittance rate of 13.1 kg m-2 d-1 and a phase change enthalpy of 115.05 J g-1 even after 100 thermal cycles. Furthermore, it displays excellent waterproofing capability, characterized by a water contact angle of 158.7° and the ability to withstand a high hydrostatic pressure of 87 kPa. In addition, the metafabric exhibits a good mechanical performance, boasting a tensile strength of 10.5 MPa. Overall, the proposed economical metafabric is an exemplary candidate material for next-generation PTM systems.

Fabrication and Characterization of Biocompatible Multilayered Elastomer Hybrid with Enhanced Water Permeation Resistance for Packaging of Implantable Biomedical Devices

This study presents the synthesis and characterization of hexadecyl-modified SiO2 (HD-SiO2) nanoparticles and their application in the fabrication of a multilayered elastomer hybrid sheet to enhance water resistance in implantable biomedical devices. The surface modification of SiO2 nanoparticles was confirmed via FT-IR and TGA analyses, showing the successful grafting of hydrophobic hexadecyl groups. FE-SEM and DLS analyses revealed spherical HD-SiO2 nanoparticles with an average size of 360 nm. A multilayered elastomer hybrid sheet, consisting of a PDMS-based circuit-protecting body, a water resistance layer of HD-SiO2, a planarization layer, and a biocompatible layer of polydopamine, was fabricated and characterized. The water resistance layer exhibited superhydrophobic properties, with a water contact angle of 154.7° and a 27% reduction in water vapor transmission rate (WVTR) compared to the circuit-protecting body alone. The device packaged with both the circuit-protecting body and water resistance layer demonstrated a tenfold increase in operational lifespan in water medium compared to the device without the water resistance layer. Cytotoxicity and cell proliferation tests on human dermal fibroblast cells (HDFn) confirmed the biocompatibility of the multilayered sheet, with no significant cytotoxicity observed over 48 h.

Spray-Coated Ultrathin and Porous Films for Physiological Sensing and Force Detection.

Epidermal electronics employed on human skin for the long term require good breathability and nonforeign wearing. In this work, we combine phase separation and spray coating to fabricate a porous and ultrathin electrode within minutes as well as micrometer-scale porous pressure sensors. The resulting electrodes show a water vapor transmission rate of 18.4 mg·cm-2·h-1, sheet resistance of 5.2 Ω/sq, and thickness below 5 μm. The introduction of the biogel further reduced the electrode-skin impedance, which is lower than that of the commercial gel electrode, indicating that the electrode can have a high degree of conformal contact with the skin. The epidermal electronics prepared by this strategy exhibit an excellent performance in force sensing. Such results strongly prove the efficiency and practicality of the strategy.

Development of Novel Cardanol-Derived Reactive Dispersing Agents for Bio-Based Anionic-Nonionic Waterborne Polyurethane.

This study successfully developed a bio-based, photocurable, anionic-nonionic dual-functional chain extender, and sulfonated cardanol-based polyethylene glycol (SCP), derived from renewable resources-cardanol and polyethylene glycol-for application in waterborne polyurethane dispersions (WPUDs). Utilizing SCP as a chain extender, WPUDs were prepared through a typical acetone process with poly(butylene adipate) (PBA), isophorone diisocyanate (IPDI), and ethylene diamine (EDA) at a constant NCO/OH ratio of 1:1. This research focused on the effects of polyethylene glycol molecular weight and SCP dosage on the particle size, stability, and film-forming properties of the WPUD. Optimal dispersion stability and film-forming performance were achieved with a polyethylene glycol molecular weight of 1500 and a PBA to SCP molar ratio of 4:1, yielding a particle size of 0.326 ± 0.010 μm and excellent storage stability over six months. The resulting WPU coatings exhibited a tensile strength of 11.4 MPa, which increased to 16.8 MPa after UV irradiation owing to the formation of a semi-interpenetrating network via the photopolymerization of cardanol's unsaturated side chains. UV cross-linking also enhanced water resistance, reducing the water absorption rate (WAR) from 18.68% to 4.21% and the water vapor transmission rate (WVTR) from 6.59 × 10-5 g·m⁻¹·Pa⁻¹·d⁻¹ to 2.26 × 10⁻⁵ g·m⁻¹·Pa⁻¹·d⁻¹, while also improving thermal stability. These findings demonstrate that SCP offers a sustainable and effective solution for developing high-performance WPU coatings.

Use of nanocelluloses from orange peel and ZnO as hybrid nanofiller in developing functionalized starch nanocomposite for edible coatings

AbstractThis study explores the formulations of orange peel nanocelluloses (NC) with tailored dimensions for the development of functionalized nanocomposites coatings on green chilies. In the present century, the valorization of agro‐waste, specifically orange peel for developing NC facilitated sustainable packaging such as edible films and coatings with improved properties has received importance. As, this approach aligns with the sustainable development goals, including reduced food waste and agro waste. For the work, the derived orange peel celluloses were acid hydrolyzed using sulfuric acid (H2SO4) and hydrochloric acid (HCl) to deliver cellulose nanofibers (CNF) and cellulose nanoparticles (CNP), respectively. The fabricated CNP and CNF were characterized using Fourier transform infrared spectroscopy (FTIR), field emission scanning electron microscopy (FESEM), and thermogravimetric analysis (TGA). The FESEM morphology showed the formation of CNP with diameter ranges from 42.4 to 108 nm and formation of CNF with diameter ranged from 27.4 to 50.5 nm. The creation of the functionalized nanocomposite was done by reinforcing with hybrid nanofillers consisting CNF, CNP consecutively with ZnO in corn starch for tailormade packaging properties in terms of mechanical, physicochemical, optical, thermal properties, and so on. The results reveal improved tensile strength, and reduced water vapor transmission rates of nanocomposite with the addition of hybrid nanofillers. Additionally, green chilies were coated with the functionalized nanocomposites prepared by different concentrations of nanofillers. The storage analysis was performed in terms of weight loss, total chlorophyll content, and microbiological analysis. The developed coatings were found to be effective in extending the shelf life of green chilies. The control samples showed significantly higher weight loss compared to coated ones. The coated samples showed significantly better firmness and total chlorophyll content after 20 days of storage. In comparison to other coatings, NC and ZnO incorporated starch‐based coating was found to be the most effective in maintaining the quality of fresh green chilies throughout the storage. Thus, incorporating NC and ZnO in starch‐based films and coatings presents a promising avenue for sustainable packaging and preservation.Highlights Agro‐waste orange peel was valorized to develop sustainable food packaging. Orange peel‐based nanocellulose was developed using H2SO4 and HCl. Nanocomposite film was developed using hybrid nanofillers. Nanocomposites provide tailored properties due to the nanofillers. Developed nanocomposite was used as edible coatings on green chilies.

Development and preservative applications of polysaccharide-based bilayer packaging films: Enhanced functional properties through metal-phenolic network-coated zein nanoparticles and biomimetic hydrophobic surfaces

This study develops an innovative bilayer biomimetic hydrophobic film, tailored to provide a sustainable and eco-friendly packaging solution for fresh produce. The outer layer, crafted from chitosan, utilized polydimethylsiloxane templating to mimic the ultra-hydrophobic surface of a lotus leaf, achieving a water contact angle exceeding 130°. The inner layer comprised sodium alginate and zein nanoparticles, enriched with citral and fortified by a metal-phenolic network to facilitate uniform dispersion and controlled release of bioactive agents. The structural design of the film significantly improved mechanical properties, evidenced by a maximum tensile strength of 29.3 ± 3.6 MPa, and enhanced hydrophobicity, reducing water solubility to 28.3 ± 1.5% and substantially decreasing water absorption. The barrier functionality of film was also strengthened, demonstrated by a lowered water vapor transmission rate of 289.3 ± 1.5 g m−2 24 h−1, and it supported extended citral release in acidic media up to 70 h. Moreover, the film exhibited robust antioxidant and antibacterial properties. In practical tests, it effectively mitigated weight loss, browning, and hardness degradation in fresh-cut apples and lotus roots, concurrently inhibiting microbial growth and extending shelf life. This study presents an effective strategy for enhancing the hydrophobicity and bioactivity of bio-based films, contributing valuable insights to the field of sustainable food packaging.