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Polyethylene (PE), a highly prevalent non‐biodegradable polymer in the field of plastics, presents a waste management issue. To alleviate this issue, bio‐based PE (bio‐PE), derived from renewable resources like corn and sugarcane, offers an environmentally friendly alternative. This review discusses various production methods of bio‐PE, including fermentation, gasification, and catalytic conversion of biomass. Interestingly, the bio‐PE production volumes and market are expanding due to the growing environmental concerns and regulatory pressures. Additionally, the production of PE and bio‐PE biocomposites using agricultural waste as filler materials, highlights the growing demand for sustainable alternatives to conventional plastics. According to previous studies, addition of ≈50% defibrillated corn and abaca fibers into bio‐PE matrix and a compatibilizer, results in the highest Young's modulus of 4.61 and 5.81 GPa, respectively. These biocomposites have potential applications in automotive, building construction, and furniture industries. Moreover, the advancement made in abiotic and biotic degradation of PE and PE biocomposites is elucidated to address their environmental impacts. Finally, the paper concludes with insights into the opportunities, challenges, and future perspectives in the sustainable production and utilization of PE and bio‐PE biocomposites. In summary, production of PE and bio‐PE biocomposites can contribute to a cleaner and sustainable future. [ABSTRACT FROM AUTHOR]

Controlling how a material interacts with light is key to optimizing its optical properties to fit a desired function or application. The most straightforward approach is to chemically or physically modify the surface exposed to incident light. An effective method of surface modification is based on the addition of core‐shell structures at the surface. Of particular importance to many technological applications are core‐shell structures with dimensions comparable to the wavelengths of light extending from the UV up to the near‐IR region of the electromagnetic spectrum, which coincides with the major part of the solar spectrum. Surface modification approaches to tailor the optical properties of materials in this range of wavelengths are increasingly relevant in the context of materials and devices used in sustainable energy applications, such as solar cells and heat‐reflective paints. These materials are useful to mitigate the current energy and climate crises by allowing for enhanced energy harvesting and improved thermal management, respectively. Here, recent progress in the fabrication and application of core‐shell micro‐/nano‐structures for the modification of light interaction with surfaces is highlighted. Some limitations and future directions for the design of core‐shell materials are also discussed. [ABSTRACT FROM AUTHOR]

Nature, especially in hot environments, triggers the phase change of the abundant metabolites in plants from solid to liquid as a survival mechanism. Therefore, taking cues from nature, these metabolites could have potential as green solvents for the dissolution of biopolymers. Because of their green credentials, plant-derived aromatic monoterpenoids have gained considerable attention for the extraction of bioactive compounds to replace toxic halogenated solvents. In this work, we report for the first time the fast dissolution of high concentration poly(3-hydroxybutyrate) (PHB) using carvacrol (5-isopropyl-2-methylphenol) – a plant metabolite – as a solvent. Remarkably, 20 wt% PHB was completely dissolved within 30 min at 100 °C, whereas a 10 wt% PHB dissolved in 21 min, and even faster dissolution for 1 wt%, 3 wt% and 5 wt% PHB. The carvacrol/PHB solution exhibited stability characterized by rheology measurements and the atomistic molecular dynamics (MD) simulations elucidate the mechanism behind carvacrol's rapid dissolution of PHB. Most importantly, the carvacrol solvent can be fully recovered by adding anti-solvents. Furthermore, the resultant highly viscous carvacrol/PHB solution could find applications in coating formulations, adhesives, and consumer care additives. [ABSTRACT FROM AUTHOR]

Polypropylene (PP) is among the most widely used commodity plastics in our everyday life due to its low cost, lightweight, easy processability, and exceptional chemical, thermo‐mechanical characteristics. The growing awareness on energy and environmental crisis has driven global efforts for creating a circular economy via developing sustainable and eco‐friendly alternatives to traditional plastics produced from fossil fuels for a variety of end‐use applications. This review paper presents a brief outline of the emerging bio‐based PP derived from renewable natural resources, covering its production routes, market analysis and potential utilizations. This contribution also provides a comprehensive review of the PP‐based biocomposites produced with diverse green fillers generated from agro‐industrial wastes, with particular emphasis on the structural modification, processing techniques, mechanical properties, and practical applications. Furthermore, given that the majority of PP products are currently destined for landfills, research progress on enhancing the degradation of PP and its biocomposites is also presented in light of the environmental concerns. Finally, a brief conclusion with discussions on challenges and future perspectives are provided. [ABSTRACT FROM AUTHOR]

Due to their remarkable features of lightweight, high strength, stiffness, high‐temperature resistance, and corrosion resistance, carbon fiber reinforced polymers (CFRPs) are extensively used in sports equipment, vehicles, aircraft, windmill blades, and other sectors. The urging need to develop a resource‐saving and environmentally responsible society requires the recycling of CFRPs. Traditional CFRPs, on the other hand, are difficult to recycle due to the permanent covalent crosslinking of polymer matrices. The combination of covalent adaptable networks (CANs) with carbon fibers (CFs) marks a new development path for closed‐loop recyclable CFRPs and polymer resins. In this review, we summarize the most recent developments of closed‐loop recyclable CFRPs from the unique paradigm of dynamic crosslinking polymers, CANs. These sophisticated materials with diverse functions, oriented towards CFs recycling and resin sustainability, are further categorized into several active domains of dynamic covalent bonds, including ester bonds, imine bonds, disulfide bonds, boronic ester bonds, and acetal linkages, etc. Finally, the possible strategies for the future design of recyclable CFPRs by combining dynamic covalent chemistry innovation with materials interface science are proposed. [ABSTRACT FROM AUTHOR]