Search Results (1,643)

The growing interest in bio-based and biodegradable polymer composites reinforced with agricultural waste reflects global efforts to reduce dependence on fossil resources and improve the sustainability of materials. However, biocomposites are not necessarily more sustainable, and their environmental performance requires careful life cycle assessment (LCA). This review critically analyses recent LCA studies of biodegradable biocomposites reinforced with agricultural waste, focusing on methodological choices, data quality, results and limitations. A systematic literature review was conducted using the Scopus database, focusing on studies from the last five years. Selected studies were examined using a structure consistent with ISO 14040, with defined data extraction categories and key questions. The analysis shows that although biocomposites often demonstrate advantages in terms of climate change and fossil resource depletion compared to traditional materials, the results vary significantly depending on the definition of the functional unit, geographical context, processing pathways, and data assumptions. Limitations include reliance on laboratory data, uncertainties, incomplete system boundaries, inconsistent allocation methods, and limited end-of-life (EoL) modelling. Overall, the review highlights the need for improved data quality, performance-based functional units, geographically representative inventories, and more standardised LCA practices to ensure meaningful comparisons and support the sustainable development of biocomposites. Full article

pH-responsive indicator films for intelligent food packaging applications are based on the embedding of a natural or synthetic dye in a polymeric substrate, preferably biobased and biodegradable. Although natural colorants like anthocyanins were extensively investigated in this respect, nature-inspired synthetic flavylium compounds could represent an alternative based on their higher stability. In this work, five novel synthetic 4′-aminoflavylium derivatives with different substitution patterns in the benzopyrylium core (compounds 1–5) were synthesized and characterized. Polyvinyl alcohol (PVA), as well as chitosan–PVA and chitosan–starch blends, were used to prepare pH-responsive indicator films having inserted each of the synthesized flavylium dyes or a natural onion peel extract. The PVA films with compounds 1 and 3, and the PVA–chitosan film with compound 1, exhibited antioxidant activity, highlighting their potential for active packaging applications. All indicator films showed pH responsiveness in the range of 2 to 12 and were subsequently tested in contact with the packaging atmosphere or in direct contact with pork and fish meat, at different temperatures (4 °C, 20 °C, and 40 °C) for 24 h to assess their colorimetric response to progressive spoilage. Although the differences were small, the films with the 7-hydroxy-4′-aminoflavylium derivative exhibited the earliest and most intense color change during storage of meat, starting from direct contact at 4 °C for 24 h, being able to identify the initial stages of meat spoilage, while the performance of the dihydroxy-substituted derivative was attenuated by incorporation in polymer matrices. This behavior was comparable to that of onion peel extract, but the synthetic flavylium derivative was more stable. The results can provide new opportunities for intelligent food packaging applications using biopolymer indicator films with 4′-aminoflavylium derivatives. Full article

Bio-based polymers are believed to often demonstrate insufficient barrier capacity and mechanical strength, especially in egg packaging processes. This current work attempted to improve the characteristics of chitosan (CS) films for egg packaging by incorporating cellulose nanocrystals (CNC) and sodium montmorillonite (MMT) nanoparticles. Such nanofillers added to the polymer matrix should reduce water vapor permeability and improve the mechanical properties of bio-nanocomposite films. Herein, coatings containing 5 wt% CNC or MMT incorporated into chitosan were applied to enhance the storability of fresh eggs over 5 weeks at ambient conditions. SEM images revealed that coatings were able to seal the eggshell pores, thereby minimizing mass transfer. After 5 weeks of storage, the Haugh unit (HU) of eggs treated with CS–CNC (67.1) and CS–MMT (64.8) appeared reasonably higher than that of control (35.2) and pure chitosan (52.1). The yolk index of eggs coated with CS–CNC (0.355) and CS–MMT (0.343) surpassed both control (0.263) and CS-coated eggs (0.308). However, pH levels in the albumen of eggs coated with CNC or MMT nanocomposite were significantly lower than others during storage. Potentially, chitosan-based nanocomposite coatings could be effective in preserving the internal quality of eggs, providing a somewhat efficient barrier against CO₂ loss with relative pH maintenance. Full article

Phytic acid (myo-inositol hexakisphosphate) and its salts, including iron, aluminum, sodium, and lanthanum phytate, are perhaps the most recent discovery in the field of bio-sourced flame retardants. Phytic acid can be extracted from sustainable resources, such as beans, cereals, and oilseeds. Its high phosphorus content (28 wt.% based on molecular weight) organized into six phosphate groups justifies the growing interest this biomolecule has attracted over the last decade in various sectors (as a corrosion inhibitor, antioxidant, and anticancer additive, among others). In addition, when exposed to a flame or an irradiative heat flux, phytic acid is a highly efficient dehydrating and char-forming agent. It also contributes to excellent flame-retardant properties when combined with other carbon sources, such as chitosan, or nitrogen-containing additives, including melamine, urea, and polyethyleneimine. This paper reviews the most recent advances in using phytic acid and its derivatives to design effective flame-retardant systems for textiles, bulk polymers, and foams. It also provides perspectives on possible future developments and implementations. Full article

Development of biodegradable polymer composites provides a sustainable alternative to conventional plastics. This study systematically investigates the effect of Eucomis autumnalis (EA) cellulose on the morphological, structural, and thermal behavior of polybutylene succinate (PBS) and polycaprolactone (PCL) blends. EA cellulose was extracted via delignification and hemicellulose removal, yielding 38% cellulose from the leaf biomass. A series of PBS/PCL/EA cellulose composites were prepared using a solution-casting method. Fourier-transform infrared spectroscopy (FTIR) confirmed retention of characteristic functional groups, with spectra dominated by PCL features, indicating the absence of new chemical bond formation between EA cellulose and the polymer matrix. X-ray powder diffraction (XRPD) revealed that EA cellulose acted as a nucleating agent, enhancing the crystallinity, especially in PCL, while slightly affecting PBS crystallization. A scanning electron microscopy (SEM) analysis demonstrated preferential localization of EA cellulose within the PBS phase, contributing to improved phase dispersion and interfacial interaction at the morphological level. Differential scanning calorimetry (DSC) showed enhanced crystallization behavior of PCL at higher EA cellulose loading (5 wt.%), with minimal influence on PBS thermal transitions. A thermogravimetric analysis (TGA) indicated that the thermal stability depends on the polymer composition and cellulose content, with higher PCL fractions contributing to an improved stability. This study provides insight into the structure–property relationships governing PBS/PCL/EA cellulose systems and highlights the potential of EA cellulose as a bio-based additive for tailoring morphological and thermal characteristics of biodegradable polymer blends. A mechanical performance evaluation is recommended for future studies to correlate structural modifications with macroscopic properties. Full article

Surface fouling remains a critical challenge for medical devices and chemosensor systems operating in biological environments, where nonspecific adsorption of proteins, cells, and microorganisms can lead to signal drift, reduced sensitivity, and shortened device lifetime. Conventional antifouling strategies rely primarily on synthetic hydrophilic polymer coatings, such as polyethylene glycol and polyvinylpyrrolidone, which are effective but face limitations related to long-term stability, thickness, and compatibility with surface-sensitive sensing modalities. In this review, we focus on hydrophobins derived from mushroom-forming and filamentous fungi as a bio-based alternative for antifouling and anti-wetting surface modification. Mushroom-derived hydrophobins are small amphiphilic proteins capable of spontaneous self-assembly into nanometer-scale films that modulate surface energy, wettability, and interfacial friction without requiring covalent functionalization. The current state of research on hydrophobin structure, classification, and self-assembly is reviewed, followed by a synthesis of reported antifouling and tribological behaviors relevant to medical and sensor-adjacent surfaces. Representative experimental observations are discussed to illustrate trends consistent with the literature, without establishing new performance benchmarks. The implications of mushroom-derived hydrophobin coatings for chemosensors and biosensors are examined, particularly with respect to signal stability, surface accessibility, and durability. Limitations and future research directions are outlined to support translation into practical sensing technologies. Full article

This work investigated the impact of energy-efficient and water-saving manufacturing procedures—specifically one-pot and hot-cold processes—on the rheological and microstructural stability of oil-in-water (O/W) emulsions (emulgels) stabilized by four distinct biopolymers and benchmarked against a synthetic polymer. Emulgels produced using these sustainable methods were directly compared against a traditional hot process. Results demonstrated that for most biopolymers, including tara gum, glucomannan, and cross-linked xanthan gum, the sustainable manufacturing procedures did not compromise overall stability and often provided beneficial polymer-specific flow profiles, such as reduced thixotropy or enhanced shear-thinning. A notable exception was the co-processed acacia/xanthan gum, where rheological data indicated that the one-pot process should be avoided due to structural degradation. Collectively, these findings broaden the applicability of sustainable manufacturing methods beyond traditional stabilizers like xanthan gum and provide additional data for process optimization, with tentative suggestions for transferability to food emulgel production. Full article

Star polymers with dense shell structures exhibit unique advantages in molecule encapsulation. The incorporation of dendronized polymers as arms into star polymers enables the formation of spherical core–shell structures with high-density chain stacking, which is of great significance for enhancing their encapsulation capabilities. Here, we report on the synthesis of a new type of star dendronized polymer consisting of oligoethylene glycol (OEG)-based dendronized polymers as the arms and gold nanoparticles (AuNPs) as the core. Due to the thickness of individual dendronized polymer arms, the morphology of star dendronized polymers was directly visualized by an atomic force microscope (AFM). These star polymers inherit characteristic thermoresponsiveness from the OEG-based dendronized linear polymers, and their thermoresponsive behavior depends mainly on the grafting density of polymer chains on the AuNP cores and the molecular weights of the polymer arms. More importantly, these star dendronized polymers exhibit a tunable encapsulation capacity to guest molecules, which can be modulated through thermally induced aggregation. By virtue of these peculiarities, these thermoresponsive star dendronized polymers with tailorable release properties hold promise as smart nanoboxes for bio-applications, including drug delivery and biosensing. Full article

Development of new polymers that cannot be achieved by using conventional catalysts has been the central research objective, and copolymerization is an effective strategy to modify the materials’ (thermal, physical, mechanical and electronic) properties. Modified half-titanocenes, Cp’TiX₂(Y) (Cp’ = cyclopentadienyl, X = Cl, Me, etc, Y = anionic donor such as phenoxide, ketimide, amidinate, etc.), are known to be effective catalysts. This review introduces several selected efforts for efficient synthesis of ethylene copolymers containing cyclic olefins, biobased conjugated dienes, and disubstituted α-olefins, including the effect of cocatalysts. Moreover, here we introduce an analysis using XAS (X-ray absorption spectroscopy), which has been recognized as a powerful method providing direct information on the catalytically active species, such as coordination numbers and the distances of the coordinated atoms as well as oxidation state and the geometry of the metal centre in catalyst solution. Full article

The global polymer waste burden has catalyzed a shift from linear “production–use–disposal” systems to circular models that prioritize recycling, reuse, and value retention. This article proposes an integrated, technology-ready roadmap for mechanical recycling and reuse of commodity and bio-based polymers via filament re-extrusion and Additive Manufacturing (AM). Building upon recent findings on performance envelopes of virgin vs. recycled Polylactic Acid (PLA) filaments processed by Fused Deposition Modeling (FDM), process parameter sensitivities (layer height, infill density) and their statistical optimization, and functional reinforcement routes (aluminum: Al, alumina: Al₂O₃, titanium: Ti, and Nano Boron Nitride: nano-BN), we articulate (1) a process–structure–property (PSP) mapping; (2) a low-defect, low-energy filament re-extrusion protocol; and (3) a graded-value strategy for upcycling mixed polymer streams. Across case analyses, we show that recycled PLA can achieve near-parity with virgin PLA when extrusion quality and printing parameters are controlled, and that ceramic/metal nanofillers enable thermal management and biocompatibility benefits crucial for durable reuse scenarios. Full article

Polymer-based systems have been shown to have a particular combination of characteristics that make them desirable in technological sectors, such as lightness, insulating properties, and easy molding during processing, as well as mechanical versatility, which is greatly due to their molecular microstructure. Nevertheless, they still present limitations in mechanical performance and use at moderate/high temperatures, considerably restricting their range of applications. Thus, great efforts have been directed towards developing strategies intended to enhance said characteristics and predict their complex mechanical behavior, with the main goal of adapting their properties to the end-use application. The present review considers the most recent developments, focusing on the research published in 2025 and early 2026, and future challenges in the mechanical behavior of polymer-based materials, being structured according to material considerations, more specifically the development of advanced (nano)composites based on high-performance matrices and functional nanoparticles, as well as bio-based polymer (nano)composites obtained from renewable sources and multifunctional smart and meta-materials for monitoring and long-term use; the development of new processing methods, focusing on advanced additive manufacturing; and the use of artificial intelligence and machine learning. All in all, the final objective is generating knowledge that will enable the preparation of components with tailor-made mechanical characteristics and functional properties, covering material design and processing. Full article

This work investigates the use of two photoactive polymers, functionalized with quantum dots (QDs) (ZnS and CdTe/ZnS), to develop optical sensing hydrogel films through their interactions. It examines their responses to light stimulation for potential biological applications. The optical and morphological properties of the films were studied, revealing photoactive surfaces. The photoactive copolymers were synthesized based on poly(maleic anhydride-alt-2-methyl-2-butene), P(MAn-alt-2MB), and poly(maleic anhydride-alt-1-octadecene), P(MAn-alt-OD), by attaching the photochromic agent, 1-(2-hydroxyethyl)-3,3-dimethylindoline-6-nitrobenzo pyran (SP). Subsequently, QD nanoparticles (ZnS or CdTe/ZnS NPs) were incorporated into the polymer solutions in the presence of a crosslinker agent, and were then spin-coated onto glass substrates under suitable conditions to produce porous-patterned films. These films were created using a one-step bio-inspired process called the breath figure (BF) method. SEM images of QD-containing samples show a photoactive porous surface resulting from a synergistic interaction between the components. The reversibility of these macroscopic properties results from photoinduced transformations at the molecular level. The light-emitting properties of the films were characterized by blue and violet fluorescence under UV light. Advances in film-forming techniques enable the creation of functional structures with important applications, such as microstructured hydrogel films for biological uses. Full article

Fluorine-free paper coatings with water- and oil-resistance properties have gained considerable attention for sustainable food packaging applications. In this study, a dual-layer coating based on chitosan (Chi) and acrylated epoxidized soybean oil (AESO), both derived from renewable and natural resources, was applied to kraft paper. The ultraviolet-cured AESO top layer formed a dense crosslinking network, while the Chi interlayer promoted strong interfacial adhesion with the kraft paper through hydrogen bonding, effectively restricting fluid penetration. The Chi/AESO₄₀/kraft paper showed markedly enhanced water repellency and oil resistance, with a reduced Cobb₆₀₀ value of 16 g m⁻² and kit rating of 12. Thermogravimetric analysis demonstrated improved thermal stability, and mechanical testing results revealed enhanced packaging-relevant strength, with the tensile strength increasing from 33 to 40 MPa and tensile index increasing from 45 to 60 kPa·m² g⁻¹; furthermore, the burst strength and index improved from 260 to 330 kPa and from 3.2 to 4.0 kPa·m² g⁻¹, respectively. Food contact tests conducted using French fries confirmed the effective barrier performance of the Chi/AESO/kraft paper, highlighting its potential for use in sustainable paper-based food packaging applications. Full article

The development of sustainable vitrimers from bio-based sources addresses the need for high-performance recyclable materials. This research describes eugenol-derived epoxy vitrimers cross-linked with adipic acid as a curing agent, focusing on comparative effects of caffeine and zinc acetate as transesterification catalysts at 5 and 10% concentrations versus a non-catalyzed control. Both catalysts acted as curing accelerators, confirmed by FTIR and DSC analyses, revealing polyhydroxyester network formation through associative ester exchange enabling topological reorganization. Zinc acetate at 10% proved most efficient, achieving the lowest apparent activation energy (116.0 kJ/mol), highest crosslinking density (ν_e = 3.42 × 10⁻³ mol/cm³), improved thermal stability with unimodal degradation profile, and substantially reduced topology freezing transition temperature (T_v = 132 °C), confirming enhanced dynamic properties. Caffeine demonstrated catalytic activity, reducing apparent activation energy to 124.4 kJ/mol at 10% and promoting rapid epoxide conversion during initial curing at moderate temperatures. Although its catalytic efficiency is moderate compared to zinc acetate, its bio-based origin and non-toxic nature make it a promising green alternative for sustainable vitrimer applications. Results demonstrate that catalyst selection is crucial for tailoring curing kinetics, network structure, and final vitrimeric properties, providing key guidelines for designing advanced circular materials from bio-based precursors. Full article

The growing environmental impact of petroleum-based plastics has intensified research into sustainable, biodegradable alternatives for food packaging. Among bio-derived polymers, carboxymethyl cellulose (CMC) has attracted increasing attention due to its abundance, non-toxicity, biodegradability, and excellent film-forming ability. Nevertheless, the intrinsic hydrophilicity and limited mechanical strength of neat CMC restrict its direct application in packaging systems. This review provides a comprehensive and critical overview of recent strategies developed between 2015 and 2025 to enhance the performance of CMC-based films for food packaging applications. Emphasis is placed on physical and chemical modification routes, including polymer blending, polyelectrolyte complex formation, incorporation of functional fillers and nanomaterials, and ionic or covalent crosslinking approaches. The influence of these strategies on key functional properties, such as mechanical behavior, water barrier performance, antimicrobial and antioxidant activity, is systematically discussed. Particular attention is given to CMC-rich systems, enabling meaningful comparison across studies. By highlighting structure–property relationships and identifying current limitations, this review aims to provide guidance for the rational design of advanced CMC-based materials as viable, eco-friendly alternatives to conventional plastic packaging. Full article