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Shape memory hydrogels (SMHs) have been the subject of great interest in recent years. However, there were few reports on the simultaneous multiple shape memory and high mechanical performance. Therefore, a novel nanocomposite (NC) hydrogel poly (acrylic acid)/Chitosan/ Laponite (PAA/CS/ Laponite) was developed by using Laponite as physical cross-linker. In order to achieve three temporary shapes, the PAA/CS/Laponite was soaked in iron chloride hexahydrate (Fe[Cl.sub.3]), sodium hydroxide (NaCl) and sodium hydroxide (NaOH) respectively to (a) form metal coordination; (b) gain the chains entanglement of chitosan; (c) get the microcrystalline structure of chitosan. The maximum shape fixity ratio of PAA/CS/Laponite can reach 100% in 1 minute and it can be restored its original shape within 5 minutes. Moreover, PAA/CS/Laponite showed excellent mechanical performance. The maximum tensile and compressive strengths were 0.73 MPa and 13.1 MPa. By comparison with PAA/CS obtained from our previous work, the tensile strength, elongation at break and compressive strength increased by 2.21 times, 1.46 times, and 3.26 times respectively. Scanning electron microscopy (SEM) showed that the obtained sample has uniform honeycomb network structures which can effectively explain why the gel has strong mechanical performance. These characteristics make PAA/CS/Laponite have huge application potential in reality. KEYWORDS mechanical performance, nano-composite hydrogel, quadruple shape-memory, 1 | INTRODUCTION Hydrogel is a kind of hydrophilic three-dimensional network polymer whose internal network is cross-linked by physical or chemical methods. With the development of researches on hydrogels, hydrogels [...]

Water polluted by organic dyes is normally present in industrial production, which seriously threatens environmental safety. Research on dye adsorption has recently been related to nanomaterials due to their large specific surface area. However, there are still some problems associated with their preparation, application, and recovery. In this study, we developed the one‐step synthesis of lignocellulosic‐Fe(OH)3 hybrid fibers by in situ growth of Fe(OH)3 nanoparticles on lignocellulosic, which could be used as effective adsorbents for dye removal. The formed Fe(OH)3 nanoparticles were dispersed homogeneously on the surface of lignocellulosic. The as‐prepared hybrid fibers featured a large absorption capacity for methylene blue, up to 150.9 mg/g. In a fixed‐bed column separation process, dye pollutants were successfully removed from the water even at a high speed of 5.0 mL/min, with the separation efficiency higher than 99.99%. Remarkably, 1.0 g of lignocellulosic‐Fe(OH)3 was capable of separating over 1200 mL of dye solution continuously and thoroughly. Notably, the underlying adsorption mechanism analyses suggested that multi‐interactions of hydrogen bonds, π–π interactions, and coordinate bonds contribute to the adsorption ability of lignocellulosic‐Fe(OH)3. [ABSTRACT FROM AUTHOR]

Oriented aerogels, emerging as a new generation of lightweight electromagnetic interference (EMI) materials, often face complex synthesis processes. While creating an orderly oriented microstructure for EMI aerogels through ambient pressure drying (APD) shows promise, it remains a significant challenge. Here, inspired by the directional grown structure of the plant, a new strategy that employs rapid precursor orientation followed by slow cross‐linking to achieve the APD of directional EMI aerogels is proposed. This approach demonstrates that low‐temperature oriented polymerization of polyaniline enables strong cross‐linking with poly(3,4‐ethylenedioxythiophene) and alginate, forming a robust conductive directional skeleton and mitigating surface tension issues during mild drying. The resulting aerogel features high conductivity (48.84 S m−1), excellent flame retardancy, and impressive compressive strength. Notably, its sturdy frame allows for further enhancement with other functional materials, such as Mxene, through re‐processing and re‐drying. The tree‐branch‐like aerogel achieves a significantly improved EMI shielding effectiveness of 50.3 dB across an ultrawideband range of 8.2–40 GHz. This strategy offers a new idea for the straightforward preparation of functional aerogels with programmability and oriented microstructures using ambient drying. [ABSTRACT FROM AUTHOR]

In the present study, a biomass‐derived metal‐phenolic networks (MPN) were used as charring agent and flame‐retardant synergist for Ethylene‐vinyl acetate/Ammonium polyphosphate (EVA/APP) composites. Compared with the polyphenol, the thermal stability of MPN was improved remarkably, making it a good match for EVA. Meanwhile, Limit oxygen index test revealed that MPN endowed EVA/APP composites with enhanced flame‐retardant performance. The reason on improvement in the flame retardancy of composites was also discussed and the corresponding mechanism was proposed. © 2018 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2019, 136, 47243. We demonstrate biomass‐derived metal‐phenolic networks (MPN) as a flame‐retardant synergist for EVA/APP composites. MPN can significantly improve the char capacity and lead to the remarkable enhancement of flame retardant performance. [ABSTRACT FROM AUTHOR]