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Increasing concerns about global food safety and security demands innovative solutions, particularly in food packaging technologies. This review paper investigates the advanced integration of natural colourimetric sensors with biopolymer‐based packaging materials, with a focus on developments over the past 5 years. These sensors change colour in response to environmental stimuli such as oxygen, temperature, pH and relative humidity, intuitively indicating food freshness and safety. The paper emphasizes the recent advancements in using natural colourants, such as alizarin, anthocyanins, betacyanins, chlorophyll, curcumin and shikonin. When combined with either natural or synthetic biopolymers, these colourants contribute to a sustainable and eco‐friendly approach to food packaging. Such technological advances could notably decrease the incidence of foodborne illnesses by signaling potential spoilage or contamination, while also addressing food wastage by providing clear indications of edibility. Although challenges remain in sensor longevity and widespread adoption, the prospects for biopolymer‐based food packaging with embedded natural colourimetric sensors are promising. [ABSTRACT FROM AUTHOR]

Polysaccharides are a class of natural biopolymers that have attracted significant attention due to their unique properties, which make them attractive for use in a wide range of applications. These biopolymers have an important role in our daily life, and designing biomaterials for biomedical applications requires careful consideration of factors such as biocompatibility, biodegradability, renewability, affordability, and availability, all of which can be achieved with polysaccharides. This review paper focuses on the use of polysaccharides in biomedical applications and provides an in‐depth analysis of the potential applications of arabinoxylan, a type of hemicellulose, in various fields, including drug delivery, infection control, tissue engineering, wound healing, and others. Arabinoxylan, which is derived from plants, is the most abundant and important class of hemicellulose and has a diverse role as a catalyst due to its biodegradability, biocompatibility, and renewable nature. Polysaccharide‐based biopolymers have applications in tissue engineering, wound covers, drug delivery systems, food preservation, and biocomposite films, making them an emerging excipient in pharmaceutical research. This review paper highlights the potential of polysaccharide‐based biopolymers in biomedical science and suggests that continued research and development will lead to broader and more innovative applications in the field. The use of polysaccharide‐based biopolymers has the potential to significantly advance healthcare and improve patient outcomes. [ABSTRACT FROM AUTHOR]

Phase change materials (PCMs) have drawn considerable attention in recent years due to their capability of storing and releasing thermal energy during phase transformation. However, traditional PCMs face challenges like limited thermal conductivity, leakage while phase transformation from solid to liquid, thermal degradation, and durability. Researchers have concentrated on creating shape‐stabilized PCMs (SSPCMs) employing polymers as the supporting matrix to overcome these difficulties and incorporating highly thermally conductive additives to improve thermal conductivity. Compared to conventional PCMs, polymer‐based SSPCMs are often more flexible, lightweight, and durable and may be easily customized according to specific applications. Various factors like PCM loading, thermal cyclability, cost‐effectiveness and environmental concerns must be considered while constructing polymer‐based SSPCMs. This review paper comprehensively explored various polymers, including polyurethane, polyacrylates, polyolefin, and so on, as promising supporting materials for SSPCMs due to their relatively high mechanical strength, compatibility with PCM, excellent thermal stability, and chemical resistance. Natural polymers like chitosan, cellulose, and starch are also considered for eco‐friendly solutions. We have also discussed about specific properties of each polymer, their cost‐effectiveness, and the environmental impact while developing such SSPCMs to guide researchers in material selection. Applications of polymer‐based SSPCMs in solar energy storage, medical devices, building materials, electronics, transportation industry, and waste heat recovery are briefly discussed. Finally, some future development areas have been discussed to attract the attention of new researchers in this field. The information provided in this review will assist readers in understanding polymer‐based SSPCM and selecting their desired polymer for support material with diverse application methods. [ABSTRACT FROM AUTHOR]

The food industry is adapting to evolving consumer demands for "healthy" and premium quality food by reducing the adverse effects of food packaging through innovative advancements in active and intelligent packaging technologies. These smart innovations offer diverse and creative ways to enhance food product quality and safety while extending shelf life. Emerging techniques are also improving the passive aspects of food packaging systems, such as thermal stability, barrier effectiveness, and mechanical strength. Notably, the use of plants, biodegradable materials, and nanomaterials in sustainable food packaging helps mitigate its negative environmental impact. By integrating intelligent, environmentally friendly, and active packaging technologies, a multipurpose food packaging system can be developed that maintains the integrity of all its components, representing the pinnacle of technological advancement in food packaging. This article reviews the fundamentals of food packaging systems, recent advancements in various packaging techniques, commercialized patents, future research trends, and the challenges that need to be addressed in food packaging. [ABSTRACT FROM AUTHOR]

Shrinking resources of fossil oil prompt search for other biosphere‐present substrates to obtain polyols, which in turn are basic components to synthesize polyurethane foams (PUF). Widely available examples are biopolymers like starch, cellulose, and chitosan. It has been shown that oligomeric chitosan as well as water soluble chitosan can be applied to obtain polyols and rigid PUF of good performance properties. In this paper, the higher molecular mass chitosans, insoluble in organic solvents and water, were converted to polyols and ultimately into foamed polyurethane plastics. The polyols were characterized by the infrared spectra (IR), 1H‐NMR, and MALDI‐ToF methods. Their properties, such as density, viscosity, surface tension and hydroxyl numbers, were determined. The PUF were obtained from these polyols of various molecular mass. The biodegradable, rigid PUF of enhanced thermal resistance were obtained. Their physical parameters like apparent density, water volume absorption, dimension stability, heat conductance, compressive strength, and heat resistance at 150 and 175°C were studied and compared with those synthesized previously from oligomeric chitosan and water soluble chitosan. [ABSTRACT FROM AUTHOR]

Electrospinning is an economical, efficient, and versatile process for the preparation of continuous nanofibers with desired patterns, tailored fiber diameters, and orientations. Since its invention, electrospinning has been utilized to prepare nanofibers from several natural polymers and synthetic polymers for use as scaffolds in tissue engineering, regeneration, and biomedical applications. Furthermore, complex scaffolds were prepared by electrospinning complex polymer solutions formulated by blending natural and synthetic organic polymers with bioceramics and other inorganic molecules. Lately, coaxial electrospinning has emerged as a promising technology in the preparation of drug‐loaded biodegradable core‐shell structured micro/nanofibers for sustained drug delivery applications. This paper will discuss the basic mechanism of electrospinning, parameters governing the electrospinning process, various materials investigated for use in the electrospinning process, and its recent advances. [ABSTRACT FROM AUTHOR]

Smart windows are gaining attention for their exceptional ability to regulate light and heat dynamics effectively. The main objective of developing dual‐responsive smart window materials lies in enhancing building applications and optimizing energy efficiency. Materials that exhibit dual responsiveness have already been reported in the literature. However, these materials have not garnered substantial research interest primarily due to prevailing economic and technological constraints. This study introduces a new methodology that uses a phase‐changing material as an electrolyte to design and customize smart windows based on individual preferences and requirements. In this paper, carboxymethyl cellulose sodium salt‐grafted copolymerpoly(2‐(dimethylamino) ethyl methacrylate)‐(N‐isopropylacrylamide)[CMC‐Na‐pDN] as an electrolyte and 1,1'‐Bis(2‐hydroxyethyl)‐4'4'‐dipyridinium hexafluorophosphate [HOEV] as a chromophore are synthesized and used to fabricate a gel‐based electro/thermochromic device (ETD). ETD exhibits dual‐chromism characteristics, transitioning from a colorless state to a purplehue at 25°C when 2V is applied. Furthermore, the purple color undergoes a transformation to blue coloration when the temperature exceeds 40°C. These phenomena arise due to the synergistic effect between its electrochromicreaction and thermochromic behavior. The ETD device exhibits a high optical constrast ∼82.5%, with a coloration efficiency (CE) of 333.1 cm2 C−1 and cyclic stability of >2000 cycles. [ABSTRACT FROM AUTHOR]

The separator is an essential component of sodium‐ion batteries (SIBs) to determine their electrochemical performances. However, the separator with high mechanical strength, good electrolyte wettability and excellent electrochemical performance remains an open challenge. Herein, a new separator consisting of amphoteric nanofibers with abundant functional groups was fabricated through supramolecular assembly of natural polymers for SIB. The uniform nanoporous structure, remarkable mechanical properties and abundant functional groups (e.g. −COOH, −NH2 and −OH) endow the separator with lower dissolution activation energy and higher ion migration numbers. These metrics enable the separator to lower the barrier for desolvation of Na+, accelerate the migration of Na+, and generate more stable solid electrolyte interphase (SEI) and cathode electrolyte interphase (CEI). The battery assembled with the amphoteric nanofiber separator shows higher specific capacity and better stability than that assembled with glass fiber (GF) separator. [ABSTRACT FROM AUTHOR]

As part of ongoing efforts to discover novel polyhydroxyalkanoate‐producing bacterial species, we embarked on characterizing the thermotolerant species, Paracoccus kondratievae, for biopolymer synthesis. Using traditional chemical and thermal characterization techniques, we found that P. kondratievae accumulates poly(3‐hydroxybutyrate) (PHB), reaching up to 46.8% of the cell's dry weight after a 24‐h incubation at 42°C. Although P. kondratievae is phylogenetically related to the prototypical polyhydroxyalkanoate producer, Paracoccus denitrificans, we observed significant differences in the PHB production dynamics between these two Paracoccus species. Notably, P. kondratievae can grow and produce PHB at elevated temperatures ranging from 42 to 47°C. Furthermore, P. kondratievae reaches its peak PHB content during the early stationary growth phase, specifically after 24 h of growth in a flask culture. This is then followed by a decline in the later stages of the stationary growth phase. The depolymerization observed in this growth phase is facilitated by the abundant presence of the PhaZ depolymerase enzyme associated with PHB granules. We observed the highest PHB levels when the cells were cultivated in a medium with glycerol as the sole carbon source and a carbon‐to‐nitrogen ratio of 10. Finally, we found that PHB production is induced as an osmotic stress response, similar to other polyhydroxyalkanoate‐producing species. [ABSTRACT FROM AUTHOR]

Nafion has been dominating the proton exchange membrane (PEM) market because of its adequacy for the proton exchange operation. However, because of its high cost, low performance at low relative humidity, and finally environmental unfriendliness, researchers have been developing and working on Nafion alternatives. In this review, we assess how biopolymers present an opportunity as an eco‐friendly material able to replace the conventional Nafion membrane in proton exchange membrane fuel cells (PEMFC). Chitosan and cellulose were the most studied in literature owing to their abundance in nature, low cost, and high affinity for water, which are sought‐after properties for PEM. In addition to that, their ease of modification through their hydroxyl or amine groups represents an opportunity to further enhance their characteristics and thus meet the criteria of diverse applications. The use of biopolymers as an adequate PEM is facing many challenges. Having a practical proton conductivity and securing the physicochemical stability of the biopolymers in fuel cell operating conditions are two of the most important challenges to overcome. Promising strategies to simultaneously address these challenges such as crosslinking, making interpenetrated networks, and making blends and composites are reported. [ABSTRACT FROM AUTHOR]

This document is a preface to a special issue of the Macromolecular Symposia journal, which features a selection of papers presented at the 5th International Conference on Soft Materials (ICSM 2022) held in Jaipur, India. The conference covered various topics related to soft materials, including biological soft matter, colloids and interfaces, polymeric materials, and materials for energy applications. The preface expresses gratitude to the organizers, contributors, reviewers, and editorial team for their efforts in making the conference and special issue a success. The document also acknowledges the support of Professor N. P. Padhy and the Soft Materials Research Society Jaipur. [Extracted from the article]