Developing biodegradable materials such as poly(lactic acid) (PLA) is a promising strategy to reduce the reliance on non‐degradable plastics and the accumulation of those wastes. However, the ...fabrication of high‐performance biodegradable films which integrate excellent mechanical and barrier properties remains a major challenge. To address this problem, the “brick and mortar” structure, one of the most effective biomimetic models, is introduced to improve the comprehensive properties of materials. Here, a PLA‐assisted exfoliation and dispersion method to prepare the PLA coated mica nanosheets (Nano‐mica/PLA) from a natural mineral phlogopite is presented. By introducing the sheer force assembly, a kind of nacre‐inspired nanocomposite film with the “brick and mortar” structure can be fabricated. Such a nacre‐inspired nanocomposite film shows excellent mechanical properties, UV‐shielding, and gas barrier properties. The overall performance of the nacre‐inspired nanocomposite film is superior to commercial plastic films, which will allow it possible to break a path for practical applications of PLA in the field of packaging.
An advanced poly(lactic acid)‐assisted exfoliation and dispersion method has been developed to prepare the poly(lactic acid) coated mica nanosheets. By introducing the sheer force assembly, a nacre‐inspired nanocomposite film with the “brick and mortar” structure is constructed with the high strength, excellent UV‐shielding performance, and barrier properties, which has great application potential in the field of packaging materials.
Widely used disposable plastic tableware is usually buried or directly discharged into the natural environment after using, which poses potential threats to the natural environment and human health. ...To solve this problem, nondegradable plastic tableware needs to be replaced by tableware composed of biodegradable structural materials with both food safety and the excellent mechanical and thermal properties. Here, a food‐safe sargassum cellulose nanofiber (SCNF) is extracted from common seaweed in an efficient and low energy consuming way under mild reaction conditions. Then, by assembling the SCNF into a dense bulk material, a strong sargassum cellulose nanofiber structural material (SCNSM) with high strength (283 MPa) and high thermal stability (>160 °C) can be prepared. The SCNSM also possesses good machinability, which can be processed into tableware with different shapes, e.g., knives and forks. The overall performance of the SCNSM‐based tableware is better than commercial plastic, wood‐based, and poly(lactic acid) tableware, which shows great application potential in the tableware field.
A food‐safe sargassum cellulose nanofiber (SCNF) is extracted through an efficient and low energy consuming way. Then, by assembling the SCNF into a dense bulk material, a strong structural material can be prepared. It possesses good machinability, which can be processed into tableware with better overall performance than that of commercial tableware, showing great application potential in the tableware field.
The widespread use of disposable plastic straws cause serious environmental problems and poses potential threats to human health, while paper straws, their most used alternatives, are not so ...satisfactory due to poor mechanical performance and unpleasant user experience. Here, a new kind of edible and microplastic‐free straw made from bacterial cellulose (BC) by biosynthesis is reported. Through the alginate coating, this BC‐based straw achieves better mechanical performance than paper straws and avoids additional adhesives. Owing to the 3D nanofiber network and strong interlayer connection, the comprehensive performance of this BC‐based straw surpasses that of commercially available counterparts, satisfying the requirements for practical use. Of particular note, the edible character provides a better user experience and a new end‐of‐life option for the straws, making the BC‐based straw a healthier and more eco‐friendly substitute for plastic straws.
A sustainable, microplastic‐free, ultrastrong, and edible straw is fabricated through biosynthesis. This bacterial cellulose‐based straw demonstrates great sustainability and excellent mechanical performance, representing an ideal substitute for plastic straws and a powerful competitor for paper straws. The 3D network of bacterial cellulose endows the straw with the ability to carry functional substances like flavor molecules, providing a better user experience.
An All‐Natural Wood‐Inspired Aerogel Han, Zi‐Meng; Sun, Wen‐Bin; Yang, Kun‐Peng ...
Angewandte Chemie International Edition,
February 1, 2023, 2023-Feb-01, 2023-02-00, 20230201, Volume:
62, Issue:
6
Journal Article
Peer reviewed
The oriented pore structure of wood endows it with a variety of outstanding properties, among which the low thermal conductivity has attracted researchers to develop wood‐like aerogels as excellent ...thermal insulation materials. However, the increasing demands of environmental protection have put forward new and strict requirements for the sustainability of aerogels. Here, we report an all‐natural wood‐inspired aerogel consisting of all‐natural ingredients and develop a method to activate the surface‐inert wood particles to construct the aerogel. The obtained wood‐inspired aerogel has channel structure similar to that of natural wood, endowing it with superior thermal insulation properties to most existing commercial sponges. In addition, remarkable fire retardancy and complete biodegradability are integrated. With the above outstanding performances, this sustainable wood‐inspired aerogel will be an ideal substitute for the existing commercial thermal insulation materials.
An interesting surface nanocrystallization method was developed to make the surface‐inert and weakly interacting wood particles better assemble to construct the aerogel. This bottom‐up method allows the preparation of large‐size composite aerogels. The wood‐inspired oriented channel structure endows the obtained aerogel with superior thermal insulation properties to natural wood and most existing commercial sponges.
Lightweight metal‐polymer composited foam has drawn considerable attention in fields of wearable electronics, acoustic and electromagnetic shielding, automotive and aerospace manufacturing, owing to ...its unique advantages like electrical conductivity and mechanical properties. Herein, a facile strategy is studied for one‐step fabrication of multifunctional liquid metal (LM) permeated expancel microspheres foam (EMLM foam) with controllable shape and size. Specifically, the formation process and mechanism of bicontinuous structure with polymer and liquid metal are explored by real‐time monitoring and finite element simulation. Both experimental and simulating results confirmed a stable 3D metal interconnected network that can be constructed with lower limit of LM (3 vol.%). In addition, based on the unique features of reversible rigidity control, lightweight, electrical conductivity, and mechanical stability, the EMLM foam can exhibit intelligent performance in tunable acoustic, energy absorption, and thermal driving repair. Combined with EMLM foam's facile preparation process and versatility, it can provide the remarkable opportunity to develop the lightweight intelligent devices.
An inside to outside strategy is proposed for one‐step fabrication of lightweight foam (density <0.3 g cm−3) with bicontinuous structure of polymer and metal. A stable conductive network with ultra‐low liquid metal content is constructed and the formation mechanism is studied in detail. The bicontinuous structure endows the foam with excellent reversible and controllable rigidity, lightweight, electrical conductivity, and mechanical stability.
Flexible supercapacitors represent an attractive technology for the next generation of wearable consumer electronics as power sources but usually suffer from relatively low energy density. It is ...highly desired to construct high‐performance electrodes for the practical applications of supercapacitors. Here, inspired by the natural structure of the spider web, an elaborate design of binder is reported through a biosynthesis process to construct flexible electrodes with both excellent mechanical properties and electrochemical performance. Through this strategy, a spider‐web‐inspired 3D structural binder enables large ion‐accessible surface area and high packing density of active electrode material as well as efficient ion transport pathways. As a result, a high areal capacitance of 4.62 F cm‐2 and a high areal energy density of 0.18 mW h cm‐2 is achieved in the composite electrodes and symmetric supercapacitors, respectively, demonstrating a promising potential to construct flexible energy storage devices for diverse practical applications.
A spider‐web‐inspired composite electrode is developed by biosynthesis process. With the 3D structural binder, electrode material particles are tightly entangled in the bacterial cellulose 3D framework, endowing electrodes with excellent mechanical performance and facilitated ion diffusion. Thereby, spider‐web‐inspired composite electrodes exhibit high areal capacitance and demonstrate excellent rate capability, making them promising wearable and portable electronic applications.
The exploration of extreme environments has become necessary for understanding and changing nature. However, the development of functional materials suitable for extreme conditions is still ...insufficient. Herein, a kind of nacre‐inspired bacterial cellulose (BC)/synthetic mica (S‐Mica) nanopaper with excellent mechanical and electrical insulating properties that has excellent tolerance to extreme conditions is reported. Benefited from the nacre‐inspired structure and the 3D network of BC, the nanopaper exhibits excellent mechanical properties, including high tensile strength (375 MPa), outstanding foldability, and bending fatigue resistance. In addition, S‐Mica arranged in layers endows the nanopaper with remarkable dielectric strength (145.7 kV mm−1) and ultralong corona resistance life. Moreover, the nanopaper is highly resistant to alternating high and low temperatures, UV light, and atomic oxygen, making it an ideal candidate for extreme environment‐resistant materials.
A nacre‐inspired nanopaper is fabricated through an aerosol‐assisted biosynthesis (AABS) strategy. Based on the AABS strategy and biomimetic structure design, the nanopaper has excellent mechanical properties, high dielectric strength, and ultralong corona resistance time. The dielectric‐mechanical comprehensive performance of the nanopaper is far beyond that of various commercial mica papers.
Flexible supercapacitors can potentially power next‐generation flexible electronics. However, the mechanical and electrochemical stability of flexible supercapacitors under different flexible ...conditions is limited by the weak bonding between adjacent layers, posing a significant hindrance to their practical applicability. Herein, based on the uninterrupted 3D network during the growth of bacterial cellulose (BC), a flexible all‐in‐one supercapacitor is cultivated through a continuous biosynthesis process. This strategy ensures the continuity of the 3D network of BC throughout the material, thereby forming a continuous electrode–separator–electrode structure. Benefitting from this bioinspired structure, the all‐in‐one supercapacitor not only achieves a high areal capacitance (3.79 F cm−2) of electrodes but also demonstrates the integration of high tensile strength (2.15 MPa), high shear strength (more than 54.6 kPa), and high bending resistance, indicating a novel pathway toward high‐performance flexible power sources.
A flexible all‐in‐one supercapacitor is cultivated through a continuous biosynthesis, harnessing uninterrupted 3D network during the growth of bacterial cellulose. The design establishes a seamless electrode–separator–electrode structure and facilitates stress transfer within and between layers. Thereby, the supercapacitor demonstrates remarkable shear and bending resistance, presenting a promising approach for the integrated development of high‐performance flexible power sources.
Plastic packaging materials are widely used because of their advantages of light weight, low cost, and convenience, especially as victuals packaging materials. Approximately 146 million metric tons ...of plastics were used for packaging in 2015, but most of these plastics had already been discarded and followed by serious white pollution. What's worse, the victuals packaging materials, especially polystyrene (PS) foam containers, can release microplastics (MPs) during daily usage. Through the combination of various appropriate chemical (eg, spectroscopy) and physical (eg, microscopy) characterization and analysis, the existence of MPs is proved and MPs can be intuitively observed. Although the impacts of MPs on ecosystems and human health are still under discussion, existing studies have shown that MPs can be integrated into habitats through soil transportation, affecting the health of various terrestrial invertebrates. Faced with this shocking reality, reducing the use of PS foam containers at high temperatures and developing healthy materials to substitute these plastics are promising solutions.
Based on the various appropriate chemical (e.g., spectroscopy) and physical (e.g., microscope) characterization and analysis, this paper provides sufficient evidence for the fact that the victuals packaging materials, especially polystyrene foam containers, can release microplastics (MPs) during daily usage. MPs have various sizes and irregularly shapes, which have potential threats to the ecosystems and human health.
Adiponectin is an important adipocytokine and plays the roles in multiple metabolic processes via binding its receptors - AdipoR1 and AdipoR2, which has also been found to participate in the ...regulation of the reproductive system of animals, in particular by influencing the secretion of ovarian steroid hormones. To further investigate the expression of adiponectin and its receptors in follicles after in vitro incubation, and their role in the steroid synthesis of laying hens’ ovaries, we performed qRT-PCR and ELISA to detect the expressions of AdipoQ, AdipoR1, and AidpoR2, and determined the key genes involved in steroidogenesis and the secretion of estradiol (E2) and progesterone (P4) through the in vitro activation of adiponectin (AipoRon) and overexpression or knockdown of AdipoR1 and AdipoR2. Our results revealed that adiponectin and its receptors wildly exist in follicles and granulosa cells, and AdipoRon (5 and 10 µg/mL) had no effect on granulosa cell proliferation and apoptosis but significantly stimulated the secretion of adiponectin and its receptors in granulosa cells after incubation for 24 h. Furthermore, AdipoRon could significantly stimulate the secretion of P4 and inhibit E2 level compared to those of the control group through modulating the key genes expression of steroidogenesis (CYP19A1, StAR, CYP11A1, FSHR, and LHR). The secretion of E2 was also decreased in granulosa cells by the treatments of overexpression and knockdown of AdipoR1/2, however, there was no difference in terms of the level of P4 and StAR expression between them if there was overexpression or knockdown of AdipoR1/2. In addition, it was shown that the secretion of E2 only exhibits a marked drop if co-processing 10 µg/mL AdipoRon and pGMLV AdipoR2 compared to single treatments. Taken together, the study highlighted the role of adiponectin and its receptors in the regulation of steroid synthesis and secretion in ovarian granulosa cells in laying hens.
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