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Growing concerns regarding plastic waste have prompted various attempts to replace plastic packaging films with biodegradable alternatives such as poly(lactic acid) (PLA). However, their low hydrolysis resistance owing to the presence of aliphatic polyesters limits the shelf life of biodegradable polymers. Hydrolysis leads to the deterioration of mechanical performance, which is a key disadvantage of biodegradable plastics. In this study, a layer-by-layer (LBL) assembly method was used for the dip-coating of biorenewable, biodegradable nanocellulose/nanochitin on the PLA surface. Additional crosslinking and compression of the coated nanofibers, each containing carboxylic acid and amine groups, respectively, were induced through electromagnetic microwave irradiation to protect the PLA film by improving hydrolysis resistance. The coatings were examined by morphological observations and water contact angle measurements. The LBL coatings of differently charged nanofibers of 10.6 μm were reduced to 40 % after microwave treatment, and the thickness does not vary after the hydrolysis experiment. Microwave irradiation increased the water contact angle owing to amide linkage formation, thereby preventing the peeling off of coating layers. Improved hydrolysis resistance inhibited the reduction in molecular weight and tensile strength. These findings could be used to develop sustainable and biodegradable plastic packaging films with a prolonged shelf life., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2023. Published by Elsevier B.V.)

Aluminum-coated polypropylene films are commonly used in food packaging because aluminum is a great gas barrier. However, recycling these films is not economically feasible. In addition, their end-of-life incineration generates harmful alumina-based particulate matter. In this study, coating layers with excellent gas-barrier properties are assembled on polypropylene films through layer-by-layer (LbL) deposition of biorenewable nanocellulose and nanochitin. The coating layers significantly reduce the transmission of oxygen and water vapors, two unfavorable gases for food packaging, through polypropylene films. The oxygen transmission rate of a 60 μm-thick, 20 LbL-coated polypropylene film decreases by approximately a hundredfold, from 1118 to 13.10 cc m -2  day -1 owing to the high crystallinity of nanocellulose and nanochitin. Its water vapor transmission rate slightly reduces from 2.43 to 2.13 g m -2  day -1 . Furthermore, the coated film is highly transparent, unfavorable to bacterial adhesion and thermally recyclable, thus promising for advanced food packaging applications., (Copyright © 2021 The Author(s). Published by Elsevier Ltd.. All rights reserved.)

Recent advancements in the utilization of naturally derived nanocellulose and nanochitin/chitosan have opened new avenues for self‐cleaning and purification applications to address environmental challenges. This review highlights the unique structural properties of bio‐based nanofibers, which are typically rich in hydroxyl groups that enhance their functionality in various industrial sectors. Through appropriate chemical modification, they can perform specific functions facilitated by carboxylic acids or amine groups. We explored the mechanisms by which these materials facilitate oil/water separation, ultrafiltration, and self‐cleaning processes, including the incorporation of inorganic nanoparticles, such as TiO2, to improve hydrophilicity and oleophobicity. Furthermore, this review discusses innovative fabrication techniques, such as spray‐assisted layer‐by‐layer assembly, which enhance the performance of nanofiber‐based coatings. We examined the potential of these materials for diverse applications, including food packaging, wastewater treatment, and personal protective equipment, emphasizing their role in promoting sustainable industrial practices. As the global emphasis on eco‐friendly solutions intensifies, continued research and development of nanocellulose and nanochitin is expected to drive significant advancements in materials science, paving the way for greener technologies. [ABSTRACT FROM AUTHOR]

Self‐healing polymeric materials, which can repair physical damage, offer promising prospects for protective applications across various industries. Although prolonged durability and resource conservation are key advantages, focusing solely on mechanical recovery may limit the market potential of these materials. The unique physical properties of self‐healing polymers, such as interfacial reduction, seamless connection lines, temperature/pressure responses, and phase transitions, enable a multitude of innovative applications. In this perspective, the diverse applications of self‐healing polymers beyond their traditional mechanical strength are emphasized and their potential in various sectors such as food packaging, damage‐reporting, radiation shielding, acoustic conservation, biomedical monitoring, and tissue regeneration is explored. With regards to the commercialization challenges, including scalability, robustness, and performance degradation under extreme conditions, strategies to overcome these limitations and promote successful industrialization are discussed. Furthermore, the potential impacts of self‐healing materials on future research directions, encompassing environmental sustainability, advanced computational techniques, integration with emerging technologies, and tailoring materials for specific applications are examined. This perspective aims to inspire interdisciplinary approaches and foster the adoption of self‐healing materials in various real‐life settings, ultimately contributing to the development of next‐generation materials. [ABSTRACT FROM AUTHOR]

While modern research into biodegradable and renewable plastics has expanded to cover a wide variety of applications, some characteristics, such as desirable elastic properties, are still difficult to achieve without the use of petroleum-based monomers. In addition, 100% biomass-based polymers are in high demand as environmental regulations increasingly require the use of biomass-based monomers. In this study, biomass-derived monomers, such as adipic acid (AA), 2,5-furandicarboxylic acid (FDCA), and 1,3-propanediol (PDO), were used to synthesize terpolyesters with elastic properties. The unsymmetrical structure of FDCA led to a spiral motif that biodegrades efficiently, and its ring structure also plays an important role as a hard elastomer domain. Applying the "odd–even effect" of PDO resulted in very high biodegradation rates, low melting points, and low degrees of crystallinity. An FDCA : AA ratio of 7 : 3 led to an elongation of around 600% and a recovery rate of 89% (to the original state) at a fixed PDO concentration. [ABSTRACT FROM AUTHOR]

Plastic packaging effectively protects food from mechanical, microbial, and chemical damage; however, oxygen and moisture permeate these plastics and spoil the food. Thus, the gas barrier function is usually imparted through metallic or halogenated polymeric coatings. However, the former blocks visible light, while the latter causes environmental concerns. Moreover, plastic packaging contaminated with food scraps and stains requires a washing process for recycling. To satisfy the key requirements for food packaging, we fabricated a (1) sustainable, (2) self-cleaning, (3) transparent, and (4) oxygen/moisture barrier coating on poly(ethylene terephthalate) (PET) film. A spray-assisted layer-by-layer assembly of negatively charged cellulose nanofibers and positively charged chitosan nanowhiskers was coated on one side of the PET film. Salt bridge-mediated synergistic interplay between these highly crystalline nanomaterials imparted a low oxygen transmission rate of less than 0.1 mL m−2 day−1. The other side of the PET film was formed with a porous surface by spray-coating of silica nanoparticles and chitosan nanowhiskers. Thereafter, the porous surface was impregnated with bio-based sunflower oil. This side repelled the contaminants and exhibited a low water vapor transmission rate of 1.4 g m−2 day−1. The gas barrier performance meets the packaging requirements for most food products. This coating has high potential for sustainable packaging applications. [ABSTRACT FROM AUTHOR]

This Review presents an overview of all-organic nanocomposites, a sustainable alternative to organic–inorganic hybrids. All-organic nanocomposites contain nanocellulose, nanochitin, and aramid nanofibers as highly rigid reinforcing fillers. They offer superior mechanical properties and lightweight characteristics suitable for diverse applications. The Review discusses various methods for preparing the organic nanofillers, including top-down and bottom-up approaches. It highlights in situ polymerization as the preferred method for incorporating these nanomaterials into polymer matrices to achieve homogeneous filler dispersion, a crucial factor for realizing desired performance. Furthermore, the Review explores several applications of all-organic nanocomposites in diverse fields including food packaging, performance-advantaged plastics, and electronic materials. Future research directions—developing sustainable production methods, expanding biomedical applications, and enhancing resistance against heat, chemicals, and radiation of all-organic nanocomposites to permit their use in extreme environments—are explored. This Review offers insights into the potential of all-organic nanocomposites to drive sustainable growth while meeting the demand for high-performance materials across various industries. [Display omitted] • All-organic nanocomposites are more sustainable than organic–inorganic hybrids. • Top-down and bottom-up productions of organic nanofillers are discussed. • In situ polymerization is robust to prepare strong all-organic nanocomposites. • These composites are used in packaging, high-performance materials, and electronics. [ABSTRACT FROM AUTHOR]