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Sustainable composite hydrogel materials with harsh environmental adaption and tolerance capability have received considerable interests but still remain as challenges. In this work, biomimetic strategy was adapted for construction of three-dimensional galactomannan (GM) hydrogels with intercalation of flexible polymer chains polyethyleneimine (PEI), biomacromolecules tannin acid (TA) and CeO2 nanoparticles (NPs). The hydrogels cross-linked with double-networks (DN) present not only pH-responsive water absorption property, but also boosted mechanical strength with highest toughness of 326 kJ/m 3 and Young's modulus of 220 kPa. Self-healing and anti-freezing capabilities were revealed for the hydrogels by maintaining of fracture elongation (23 %) and fracture strength (250 kPa). TA, CeO2 NPs as well as the amide groups in PEI of the hydrogels introduced excellent bacterial prohibition performance on both Bacillus subtilis (B. subtilis) and Escherichia coli (E. coli). Also, due to the existence of the free ions, the hydrogels exhibited electric conductive properties, with wide-range high sensitivity and long-time conductive stability. In addition, various tensile strain degrees were related to the conductive resistance values, and the great recovery performance was proved by cyclic tensile-conductive tests for 3000 times. Therefore, the proposed GM-based hydrogels displayed great potentials as strain sensors that are adaptable and tolerant to various environmental conditions., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2024. Published by Elsevier B.V.)

In recent years, flexible devices have gained rapid development with great potential in daily life. As the core component of wearable devices, flexible tactile sensors are prized for their excellent properties such as lightweight, stretchable and foldable. Consequently, numerous high-performance sensors have been developed, along with an array of innovative fabrication processes. It has been recognized that the improvement of the single performance index for flexible tactile sensors is not enough for practical sensing applications. Therefore, balancing and optimization of overall performance of the sensor are extensively anticipated. Furthermore, new functional characteristics are required for practical applications, such as freeze resistance, corrosion resistance, self-cleaning, and degradability. From a bionic perspective, the overall performance of a sensor can be optimized by constructing bionic microstructures which can deliver additional functional features. This review briefly summarizes the latest developments in bionic microstructures for different types of tactile sensors and critically analyzes the sensing performance of fabricated flexible tactile sensors. Based on this, the application prospects of bionic microstructure-based tactile sensors in human detection and human-machine interaction devices are introduced., Competing Interests: Declaration of Competing Interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2023. Published by Elsevier B.V.)

The starch composite films (SCFs) will be one of the best alternative packaging materials to petroleum based plastic films, which mitigates white pollution and energy consumption. However, weak mechanical stability, water resistance, and dyeability has hindered the application of SCFs. Herein, a bioinspired robust SCFs with super-hydrophobicity and excellent structural colors were prepared by fiber-reinforcement and assembling SiO 2 /Polydimethylsiloxane (PDMS) amorphous arrays on the surface of SCFs. The properties of the designed SCFs were investigated by various methods including scanning electron microscope (SEM), Fourier transform infrared spectroscopy (FT-IR), X-ray diffraction (XRD), thermo-gravimetric analysis (TGA), a tensile test, contact angle (CA) test, and an optical test. The results showed that the obtained SCFs possessed a higher tensile strength (55.17 MPa) attributed to the formed abundant hydrogen bonds between the molecular chains of the starch, cellulose fiber, and polyvinyl alcohol. Benefiting from the nanostructure with rough surface which were modified by materials with low surface free energy, the contact angle and sliding angle of the film reached up to 154° and 2°, respectively. The colors which were produced by the constructive interference of the coherent scattered light could cover all of the visible regions by tuning the diameters of the SiO 2 nanoparticles. The strategy in the present study not only reinforces the mechanical strength and water resistance of SCFs but also provides an environmentally friendly way to color the them, which shows unprecedented application potential in packaging materials of the starch composite films.