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Recent advancements in the utilization of naturally derived nanocellulose and nanochitin/chitosan have opened new avenues for self‐cleaning and purification applications to address environmental challenges. This review highlights the unique structural properties of bio‐based nanofibers, which are typically rich in hydroxyl groups that enhance their functionality in various industrial sectors. Through appropriate chemical modification, they can perform specific functions facilitated by carboxylic acids or amine groups. We explored the mechanisms by which these materials facilitate oil/water separation, ultrafiltration, and self‐cleaning processes, including the incorporation of inorganic nanoparticles, such as TiO2, to improve hydrophilicity and oleophobicity. Furthermore, this review discusses innovative fabrication techniques, such as spray‐assisted layer‐by‐layer assembly, which enhance the performance of nanofiber‐based coatings. We examined the potential of these materials for diverse applications, including food packaging, wastewater treatment, and personal protective equipment, emphasizing their role in promoting sustainable industrial practices. As the global emphasis on eco‐friendly solutions intensifies, continued research and development of nanocellulose and nanochitin is expected to drive significant advancements in materials science, paving the way for greener technologies. [ABSTRACT FROM AUTHOR]

Self‐healing polymeric materials, which can repair physical damage, offer promising prospects for protective applications across various industries. Although prolonged durability and resource conservation are key advantages, focusing solely on mechanical recovery may limit the market potential of these materials. The unique physical properties of self‐healing polymers, such as interfacial reduction, seamless connection lines, temperature/pressure responses, and phase transitions, enable a multitude of innovative applications. In this perspective, the diverse applications of self‐healing polymers beyond their traditional mechanical strength are emphasized and their potential in various sectors such as food packaging, damage‐reporting, radiation shielding, acoustic conservation, biomedical monitoring, and tissue regeneration is explored. With regards to the commercialization challenges, including scalability, robustness, and performance degradation under extreme conditions, strategies to overcome these limitations and promote successful industrialization are discussed. Furthermore, the potential impacts of self‐healing materials on future research directions, encompassing environmental sustainability, advanced computational techniques, integration with emerging technologies, and tailoring materials for specific applications are examined. This perspective aims to inspire interdisciplinary approaches and foster the adoption of self‐healing materials in various real‐life settings, ultimately contributing to the development of next‐generation materials. [ABSTRACT FROM AUTHOR]

Among plastic items, single‐use straws are particularly detrimental to marine ecosystems because such straws, including those made of poly(lactic acid) (PLA), are sharp and extremely slowly degradable in the ocean. While paper straws are promising alternatives, they exhibit hydration‐induced swelling even when coated with a non‐degradable plastic coating and promote effervescence (fizzing) in soft drinks owing to their surface heterogeneities. In this study, upgraded paper straw is coated with poly(butylene succinate) cellulose nanocrystal (PBS/CNC) composites. CNC increases adhesion to paper owing to their similar chemical structures, optimizes crystalline PBS spherulites through effective nucleation, and reinforces the matrix through its anisotropic and rigid features. The straws are not only anti‐fizzing when used with soft drinks owing to their homogeneous and seamless surface coatings, but also highly water‐resistant and tough owing to their watertight surfaces. All degradable components effectively decompose under aerobic composting and in the marine environment. This technology contributes to United Nations Sustainable Development Goal 14 (Life Below Water). [ABSTRACT FROM AUTHOR]

The demand for face masks is increasing exponentially due to the coronavirus pandemic and issues associated with airborne particulate matter (PM). However, both conventional electrostatic‐ and nanosieve‐based mask filters are single‐use and are not degradable or recyclable, which creates serious waste problems. In addition, the former loses function under humid conditions, while the latter operates with a significant air‐pressure drop and suffers from relatively fast pore blockage. Herein, a biodegradable, moisture‐resistant, highly breathable, and high‐performance fibrous mask filter is developed. Briefly, two biodegradable microfiber and nanofiber mats are integrated into a Janus membrane filter and then coated by cationically charged chitosan nanowhiskers. This filter is as efficient as the commercial N95 filter and removes 98.3% of 2.5 µm PM. The nanofiber physically sieves fine PM and the microfiber provides a low pressure differential of 59 Pa, which is comfortable for human breathing. In contrast to the dramatic performance decline of the commercial N95 filter when exposed to moisture, this filter exhibits negligible performance loss and is therefore multi‐usable because the permanent dipoles of the chitosan adsorb ultrafine PM (e.g., nitrogen and sulfur oxides). Importantly, this filter completely decomposes within 4 weeks in composting soil. [ABSTRACT FROM AUTHOR]

Owing to the unique mass and heat transfer, fluidic‐flow control systems or reactors can potentially provide advantages for organic and inorganic syntheses compared to the static reactors. In this study, it is demonstrated that a fluid dynamic reactor based on Taylor–Couette (T–C) flow provides high‐throughput processes for the exfoliation of hexagonal boron nitride (hBN), syntheses of metal‐nanoparticle‐(NP)‐deposited hBN nanohybrids, and their glycolysis reactions of poly(ethylene terephthalate) (PET). The mechanical shear force and dynamic mixing behavior of the T–C flow lead to a stable colloidal suspension of exfoliated hBN sheets with a high exfoliation yield of 77.9% and high production rate of 0.48 g h−1. A fast synthesis of metal NPs (Pd, Pt, Ag, and RuO2 NPs) onto the hBN surface is achieved by using the controlled T–C flow within only 2 min owing to the efficient mass and heat transfer of the T–C flow. The T–C flow considerably reduces the reaction time (30 min) and temperature (100 °C) for the Pd/hBN‐catalyst‐based glycolysis reaction of PET to bis(2‐hydroxyethyl) terephthalate compared to those of the conventional static reaction that is performed above 200 °C for 120 min. [ABSTRACT FROM AUTHOR]

Abstract: Highly conductive and ultrathin 2D nanosheets are of importance for the development of portable electronics and electric vehicles. However, scalable production and rational design for highly electronic and ionic conductive 2D nanosheets still remain a challenge. Herein, an industrially adoptable fluid dynamic exfoliation process is reported to produce large quantities of ionic liquid (IL)‐functionalized metallic phase MoS2 (m‐MoS2) and defect‐free graphene (Gr) sheets. Hybrid 2D–2D layered films are also fabricated by incorporating Gr sheets into compact m‐MoS2 films. The incorporated IL functionalities and Gr sheets prevent aggregation and restacking of the m‐MoS2 sheets, thereby creating efficient and rapid ion and electron pathways in the hybrid films. The hybrid film with a high packing density of 2.02 g cm−3 has an outstanding volumetric capacitance of 1430.5 F cm−3 at 1 A g−1 and an extremely high rate capability of 80% retention at 1000 A g−1. The flexible supercapacitor assembled using a polymer‐gel electrolyte exhibits excellent resilience to harsh electrochemical and mechanical conditions while maintaining an impressive rate performance and long cycle life. Successful achievement of an ultrahigh volumetric energy density (1.14 W h cm−3) using an organic electrolyte with a wide cell voltage of ≈3.5 V is demonstrated. [ABSTRACT FROM AUTHOR]

ABSTRACT A high molecular weight polysilsesquioxane (LPMSQ)/ZnO nanocomposite was prepared by blending a methacryl-substituted polysilsesquioxane and PMMA-coated ZnO nanoparticle (NP) followed by UV-curing process. These LPMSQ/ZnO nanocomposites gave high thermal and mechanical stabilities originated from the rigid ladder structured siloxane backbone of LPMSQ. The polysilsesquioxane and surface-modified ZnO nanoparticles showed excellent compatibility between MMA groups in LPMSQ- and PMMA-capped ZnO nanoparticles to give well-dispersed LPMSQ/ZnO nanocomposites. Mechanically pliant and flexible free standing films were obtained, and the photo and optical properties of these hybrid nanocomposites were examined. The high photoluminescent properties were maintained even after severe thermal treatments exceeding 400°C. © 2015 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2015, 132, 42333. [ABSTRACT FROM AUTHOR]

Biodegradable Facemasks: Biodegradable, Efficient, and Breathable Multi-Use Face Mask Filter (Adv. Sci. 6/2021) In article number 2003155, Jeyoung Park, Dongyeop X. Oh, Sung Yeon Hwang, and co-workers report a biodegradable, moisture-resistant, highly efficient, and breathable face mask filter based on easy-to obtain poly(butylene succinate) coated with chitosan nanowhiskers. Integrated microfiber/nanofiber mats present a particulate matter removal efficiency as high as the commercial N95 filter due to a combination of physical sieving and electrostatic adsorption. [Extracted from the article]

Some polymer mixture systems become immiscible above a specific temperature, the so‐called lower critical solution temperature (LCST). In this work, the LCST behavior of a mixture of poly(ethylene oxide)‐block‐poly(propylene oxide)‐block‐poly(ethylene oxide) triblock copolymers and phenolic resin oligomers is observed, and the corresponding phase transition is exploited to develop a facile route to hierarchically structured carbon monoliths. Whereas evaporation‐induced self‐assembly generates hexagonal channels in the monoliths, an additional phase transition at the LCST leads to an ordered arrangement of isolated pores. The fabrication method involves annealing the gel‐phased mixture with polymeric microbeads in a 3D‐structured mold at the LCST, followed by thermosetting and a carbonization process. The LCST phase transition behavior is observed experimentally by in situ small‐angle X‐ray scattering, optical transparency measurements, differential scanning calorimetry, and infrared spectroscopy. The fundamental mechanism of the LCST phase transition is further investigated by atomistic molecular dynamics simulations. [ABSTRACT FROM AUTHOR]

In article number 1802952, Young‐Kyu Han, Bong Gill Choi, Do Hyun Kim, and co‐workers report a fast, scalable, and versatile hydraulic power process to make highly stable 2D nanosheet dispersions. Highly stable 2D nanosheet dispersions can be conveniently processed by vacuum filtration and inkjet printing for highly conductive circuits and high‐performance energy storage film electrodes. [ABSTRACT FROM AUTHOR]

As 2D‐nanosheet dispersions greatly facilitate solution‐based processes, the preparation of 2D nanosheets in various solvents offers considerable potential in many applications, from electronics to energy storage and conversion. However, significant improvements are required in production cost, scalability, yield, and processability to realize the full potential of 2D nanosheets. Herein, a fast, scalable, and versatile hydraulic power process for the large‐scale production of 2D nanosheets (graphene, MoS2, and boron nitride) dispersed in water is presented. A controlled, wavy Taylor‐vortex flow allows for a high‐shear mixing process with efficient mass transfer. The use of an ionic liquid dramatically improves the exfoliation of 2D materials, resulting in an extremely high yield (76.9%), a high concentration (20 mg mL−1), and a high production rate (8.6 g h−1). The computational fluid dynamics simulations reveal that the improved exfoliation performance originates from the high‐shear mixing process, and the first‐principles calculations rationalize this performance via the high adsorption energies of ionic liquids on 2D nanosheets. The highly stable 2D nanosheet dispersions efficiently facilitating the postprocesses of vacuum filtration and inkjet printing, resulting in highly conductive circuits and high‐performance film electrodes for energy‐storage applications, are also demonstrated. A fast, scalable, and versatile hydraulic power process is developed for the large scale of highly stable 2D nanosheet (graphene, MoS2, and boron nitride) dispersions, facilitating the postprocesses of vacuum filtration and inkjet printing for highly conductive circuits and high‐performance energy storage film electrodes. [ABSTRACT FROM AUTHOR]