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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]

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]

The structural battery is a multifunctional energy storage device that aims to address the weight and volume efficiency issues that conventional batteries face, especially in electric transportation. By combining the functions of mechanical load bearing and energy storage, structural batteries can reduce the reliance on, or even eventually replace the main power source in an electric vehicle or a drone. However, one of the key challenges to be addressed before achieving multifunctionality in structural batteries would be the design of a suitable multifunctional structural battery electrolyte. The structural battery electrolyte is the constituent that provides mechanical integrity under flexural loads or impact and hence determines the electrochemical and much of the mechanical performance of a structural battery device. This concept paper aims to cover the key considerations and challenges facing the design of structural battery electrolytes. In addition, the main approaches to surmount these challenges are highlighted, keeping design aspects like sustainability and recyclability in view. [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]

A novel route to lignin epoxy composites is developed through covalent incorporation of depolymerized lignin epoxide into amine-cured epoxy matrix. The partially depolymerized lignin is first epoxidized with epichlorohydrin and the resultant depolymerized lignin epoxide shows decreased solubility in common organic solvents. When dispersed in epoxy matrix and cured, the depolymerized lignin epoxide is integrated into epoxy networks in the form of submicron aggregates. The resulting lignin epoxy composites show improved mechanical properties compared with neat epoxy. At a loading content of 1.0 wt% of degraded lignin epoxide, the Young's modulus and the critical stress intensity factor ( KIC) of the composite increase by 10% and 25%, respectively, in comparison with those of neat epoxy, while the glass transition temperature is little changed. This method presents a promising way to convert wasteful lignin to an alternative epoxy monomer and effective additive in epoxy composites. [ABSTRACT FROM AUTHOR]

A lightweight and flexible thermoelectric generator (TEG) based on monolithic designed single-walled carbon nanotubes (SWCNT) is successfully developed, which can effectively harvest electricity from hybrid sources of body heat and solar light with high energy output. By properly selecting SWCNT dispersion solvents, SWCNT films with an optimal p-type power factor of 526 μW m−1 K−2, and n-type power factor of 489 μW m−1 K−2 are achieved, among the highest reported power factors for solution-processed CNT-based films. Monolithic TEG based on the optimized SWCNT films leads to exceptionally high device performance both under constant heat and sunlight. The 8-leg TEG exhibits output power density over 110.2 μW cm−2 and 25.3 μW g−1 with a temperature gradient of 28 K, which is among the best energy-harvesting performance of CNT-based TEG. In addition, a large temperature gradient over 22.1 K is generated under AM1.5 1 sun illumination, owing to the SWCNT films act not only as TE modules but also solar-light absorber, and the TEG yields a record-high output power density of 66.0 μW cm−2 and 15.1 μW g−1 under 1 sun. Our TEG design based on SWCNT shows great potential in powering flexible micro-watt electronics by effectively harvesting electricity from both body heat and sunlight. High power-output monolithic SWCNT-based thermoelectric generator which realizes efficient hybrid energy harvesting from body heat and sunlight developed with high p- and n-type power factors achieved from solution-processed SWCNT films with solvent-optimized thermoelectric properties. [Display omitted] • High p/n-type power factors achieved for solution-processed SWCNT films with solvent-optimized thermoelectric properties. • The mechanisms between thermoelectric properties and dispersing solvent selection studied. • High power-output SWCNT-based thermoelectric generator with efficient energy harvesting from body heat and sunlight. [ABSTRACT FROM AUTHOR]