Polyphenols represent a highly abundant group of plant-derived natural compounds, characterized by remarkable structural diversity and potent antioxidant activity. Based on their chemical structures, polyphenols are broadly categorized into flavonoids, phenolic acids, stilbenes, tannins and lignans. Among these polyphenolic groups, tannins stand out for their large and complex polyphenolic frameworks and strong metal-chelating abilities. Tannic acid, a well-known hydrolyzable tannin, is one of the most extensively utilized polyphenols because of its dense phenolic composition, strong metal-chelating ability and capacity to form diverse non-covalent interactions. This review highlights recent advancements and applications of tannic acid-based micro- and nano-formulations, with particular emphasis on their roles in emulsion stabilization, enhancement of UV-barrier properties and food safety sensor applications.

Polymer composites are widely used in indoor and outdoor applications owing to their high strength-to-weight ratio, corrosion resistance, and design flexibility. However, exposure to environmental factors such as ultraviolet (UV) radiation, humidity, temperature fluctuations, and biological agents significantly affect their long-term durability and performance. In this review, we comprehensively examine the degradation mechanisms of polymer composites under both natural and accelerated weathering, with particular emphasis on degradation mechanisms, characterization techniques, and durability assessment. We critically discuss the fundamental degradation mechanisms, including photo-oxidation, hydrolysis, polymer chain scission, crosslinking and interfacial debonding. We also evaluated accelerated weathering techniques, conducted under standardized testing conditions, for their ability to simulate long-term outdoor exposure within significantly shorter timeframes, by controlling key environmental parameters such as UV radiation, humidity, and temperature. We also examine the influence of reinforcements, including natural fibres, synthetic fibres, and nanofillers, on the weathering resistance of polymer composites. Attention is given to natural fibre–reinforced composites because their inherent hydrophilicity promotes moisture absorption, accelerating degradation and weakening the fibre–matrix interface. Furthermore, we critically evaluate the effects of weathering on the mechanical properties, crystalline structure and barrier performance of polymer composite films, and discuss recent advances in enhancing weather resistance through hybridization, surface modification, and the incorporation of stabilizing additives. Finally, the review highlights the key challenges and future research directions for the development of durable, high-performance, and sustainable polymer composite systems for long-term outdoor applications.

The growing focus on sustainability, eco-friendly technologies, decarbonization, and reducing carbon footprints shapes current industry challenges. This article reviews the potential of cinnamon as a bio-additive for polymer stabilization in packaging. Samples were prepared from ethylene-norbornene copolymer (Topas), a cyclic olefin copolymer known for purity, transparency, and low gas permeability, and poly(lactic acid) (PLA), a bio-based alternative to petroleum plastics. Cinnamon powder was added in 0.5, 1.0, and 1.5 wt%. After solar and thermo-oxidative aging, hydrophobicity, chemical composition, mechanical, and color properties were analyzed. Results showed higher hydrophobicity and resistance to hydrolytic degradation due to reduced water penetration. PLA, normally brittle, became more flexible, with 0.5 wt% cinnamon showing optimal performance after 100 h of solar aging, similar to Topas composites. Overall, PLA and cyclic olefin copolymer (COC) films with cinnamon improved durability, extended food shelf life, and acted as natural color indicators of material aging.

In this work, we have developed a novel absorbent material using chitosan (CS), and further it was structurally modified via reaction with thiocarbaldehyde, forming a Schiff base intermediate. Simultaneously, graphene oxide was functionalized at the C-6 position of CS through an effective esterification process and composited with the incorporation of molybdenum disulfide (MoS₂) nanoparticles to synthesize a hybrid adsorbent material. The resulting material was characterized using Fourier transform infrared spectroscopy (FTIR), thermogravimetric analysis (TGA), X-ray diffraction (XRD), and scanning electron microscopy (SEM). The synthesized adsorbent was subjected to the adsorptive removal of Cu(II) and Cr(VI) ions from dilute solutions. The maximum uptake of 66.66 mg/g for Cu(II) and 76.92 mg/g for Cr(VI) were recorded during the adsorption process, further following pseudo-second-order kinetics adsorptive nature and fitted well with the Langmuir isotherm model. Desorption studies indicated the material’s reusability, and the thermodynamic studies indicated a spontaneity with an endothermic adsorptive nature. These studies highlight the material’s potential as an effective adsorbent as a sustainable approach for efficient environmental remediation.

In this study, a new plastic film with antiviral and antibacterial properties was developed using modified cassava starch with glycidyltrimethylammonium chloride (GTMAC) and reinforced by crystalline nanocellulose (CNC), called Q-CS/CNC. For comparison, a control film (Q-CS) was produced without the addition of CNC. Elemental analysis revealed a degree of substitution (DS) of 0.552, indicating the replacement of the OH groups of starch by the NR₄⁺ groups of GTMAC during the quaternization reaction. The addition of CNC resulted in significant increases (p < 0.05) of 38.9, 38.2, and 43.1% in thickness, opacity, and water vapor permeability measurements, respectively, compared to Q-CS. Incorporating CNC also contributed to an increase of 43.6% in tensile strength and 109% in stiffness but slightly decreased thermal stability. The Q-CS/CNC film demonstrated efficacy by inactivating 99% of the coronavirus in 1 min and inhibiting the growth of Staphylococcus aureus and Escherichia coli. This action is attributed to the electrostatic interaction of quaternary amino groups, grafted onto starch, with the phospholipid membrane of microorganisms, resulting in the inactivation of these microorganisms. Therefore, these results highlight the potential use of Q-CS/CNC film as antimicrobial packaging, especially against coronavirus.