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Developing adsorbent materials based on biomass that can be easily recycled and reused to remove water pollutants has received widespread attention. A novel method for the preparation of calcium alginate/poly (vinyl alcohol)/boric acid (as–synthesized Ca-APB) aerogel fibers for highly efficient adsorption of methylene blue by directed freezing wet–spinning was presented in this paper. The Ca-APB-0.5 aerogel fibers exhibited a hierarchical structure consisting of a honeycomb micron pore structure with mesopores walls, with a maximum adsorption capacity of 508.99 mg/g in 5 h at 293 K. Meanwhile, the experimental data for Ca-APB-0.5 aerogel fibers showed the best fit to the Freundlich model and pseudo–second–order model. Moreover, the adsorption capacity was investigated for three consecutive cycles, with 469.37, 457.19, and 439.77 mg/g in the first, second, and third cycles, respectively. This paper proves that the hierarchical structure of alginate-based aerogel fiber is an effective dye adsorption material with high efficiency, reusability, and eco-friendliness. [Display omitted] • Robust alginate–based aerogel fibers via directed freezing–wet spinning. • Restriction of Ca2+ complexation by boric acid reduces the consumption of active groups. • Efficient adsorbent based on multi-active groups and hierarchical structure. • Micron macropores for channeling and nanopores for adsorption, inspired by soil pores. • Aerogel fibers realized high efficiency, reusability, and eco-friendliness. [ABSTRACT FROM AUTHOR]

To solve the inherent problems of conductive hydrogels, such as relatively low mechanical properties and fatigue resistance, inability to work after water loss, and difficulty weaving. In this study, the borax-crosslinked polyvinyl alcohol/k-carrageenan (kC) conducting hydrogels (BPK KOH) were prepared by a simple one-pot method, and KOH treatment was used instead of the cumbersome and time-consuming freeze-thaw cycle to improve the comprehensive properties. The KOH treatment increased the hydrogel hydrogen bonding content by 7.72 % and synergized with the induction of kC by K+ to enhance the tensile and compressive strengths by 8.12 and 34.6 times, respectively. Meanwhile, the BPK KOH hydrogel's fatigue resistance and shape recovery after water loss were improved. Additionally, the BPK KOH hydrogels can be monitored for finger bending, showing clear and stable differences in electrical signals. BPK KOH hydrogels combined with Morse code realize applications in information transmission and encryption/decryption. Notably, introducing KOH ensures the molding and preparation of BPK KOH hydrogel fibers while having good signal responsiveness and monitoring ability. More importantly, it can be woven into fabrics that can be loaded with heavy weights, which has the potential to be directly applied in smart wearables. This work provides new ideas for applying flexible sensors and wearable smart textiles. [Display omitted] • The KOH treatment can replace the traditional freeze-thaw cycles and improve the comprehensive properties of the hydrogels. • Hydrogen bonding and densely crosslinked network structure endow BPK KOH hydrogels with good mechanical properties. • The sensors assembled by BPK KOH hydrogels combined with Morse code to achieve information transfer and encryption/decryption. • Wet spinning confirms BPK composite system's spinnability, while KOH treatment similarly affects BPK hydrogel fibers. [ABSTRACT FROM AUTHOR]

[Display omitted] • Nanofiber membranes with good microscopic morphology and high porosity containing AKP were successfully prepared. • AKP increased the nanofiber membranes' cell coverage and relative cell viability. • The ordered secondary structure content of AKP showed a positive correlation with the its intermolecular hydrogen bonds. • AKP improved the thermal stability and mechanical properties of nanofiber membranes. Polyvinyl alcohol (PVA) and polyethylene oxide (PEO) nanofiber membranes with high porosity and specific surface area supply a suitable structural environment for cell growth, however the difficulty of cells adhesion to and growth has tremendously limited their application in biomedical materials. In this work, by incorporating Antarctic krill protein (AKP), the problem in cells adhesion and growth is successfully addressed for PVA/PEO nanofiber membranes. Meanwhile, it is worth noting that the problem that AKP is difficult to prepare nanofibers by electrospinning process is also effectively avoided. The intermolecular interactions ensure the uniform dispersion of AKP in the nanofiber membranes. And both the crystal structure content of nanofiber membranes and the ordered secondary structure content of AKP reach the maximum values of 37.41 % and 52.17 % at the AKP content of 20 %. The tensile strength is improved by 13.46 % notably. More importantly, the introduction of AKP enhances cell proliferation and viability and adds more recognition sites for cell attachment, solving the problem of difficult cell adhesion and growth. Thus, as-prepared nanofiber membranes containing AKP can supply suitable structural environment and excellent biocompatibility, for cell growth and reproduction. It is expected to be an essential candidate in biomedical materials with potential application prospects. [ABSTRACT FROM AUTHOR]

To prepare novel medical dressings with excellent comprehensive properties, this work uses the polyvinyl alcohol-allyl polyethylene glycol graft copolymer (PVA-g-APEG) synthesized in our previous work as a modifier. The polyvinyl alcohol (PVA)/polyethylene oxide (PEO)/PVA-g-APEG nanofiber membranes with different PVA-g-APEG contents are successfully prepared by electrospinning technology. The biomimetic natural extracellular matrix structure of nanofiber membranes is achieved by regulating the PVA-g-APEG contents. As the content of PVA-g-APEG is 4 wt%, the diameter distribution of nanofibers is the narrowest. The average diameter of nanofibers reaches the minimum value of 267.18 nm, and the porosity of nanofiber membranes reaches the maximum value of 77.90%. Meanwhile, nanofiber membranes possess excellent biocompatibility. The absorption capacity of the nanofiber membranes for different liquids is improved with higher PVA-g-APEG content. The nanofiber membranes become soft and slippery after contact with liquid, effectively avoiding adhesion with cells. The cell proliferation rate is higher than 100%, and the cytotoxicity grade is 0. Additionally, the mechanisms of intermolecular interactions, crystallization and mechanical properties change of nanofiber membranes are discussed systematically. It provides a method and idea for preparing high-strength PVA/PEO nanofiber membranes and realizing the practical application of PVA/PEO composite systems in medical dressings. [Display omitted] [ABSTRACT FROM AUTHOR]