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• The Mannich-based curcumin-modified strategy drew inspiration from plant cell walls. • Curcumin-modified cellulose was produced with large-scale and versatile method. • This modified cellulose showed durable antimicrobial and UV-protective performance. Cellulose is a versatile and renewable material used in clinical settings for dressings, masks, and bedding. However, adding functions like UV-shielding, antiviral, and antibacterial properties can be challenging due to its poor adhesion and reduced effectiveness over time. Inspired by the natural structure of plant cell walls, we propose a scalable and versatile strategy by introducing curcumin and lysine to the cellulose surface via the Mannich reaction to achieve a durable antimicrobial and UV-protective cellulose surface. The ensuring chemical configuration was characterized through Nuclear magnetic resonance spectroscopy, Fourier transform infrared spectroscopy, and X-ray photoelectron spectroscopy. Additionally, X-ray diffraction analysis confirmed that the modification occurred exclusively at the cellulose surface. We found curcumin-modified sulfated nanocellulose nanofibrils (CL-SCNF) entirely block ultraviolet rays at wavelengths of 200–400 nm (UVA, UVB, and UVC) while providing 82.1 % transparency in the visible spectrum. The resultant silver bonding cellulose products exhibit high antiviral, antibacterial, and antifungal performance against bacterial phage-X174, Escherichia coli, Staphylococcus aureus, and Candida albicans. Furthermore, the strong coordination bonding of silver ions with the β -diketone system endows the final textiles with good washing stability, which can maintain 99 % of antimicrobial activity after repeated washing. This eco-friendly and highly scalable method for fabricating antimicrobial cellulose surfaces will be attractive to manufacturers of protective equipment and textiles, as it offers great potential for applications in a wide range of fields. [ABSTRACT FROM AUTHOR]

[Display omitted] • The CPB aerogel was fabricated via the formation of dynamic enamine bonds. • A maximum adsorption capacity toward MO up to 1013.11 mg g-1 was achieved at 25 °C. • The aerogel could be used to selectively remove anionic dyes form ternary mixtures. • The adsorbent exhibited great antibacterial activity. • There were two possible strategies for recycling the absorbed CPB aerogel.ab. Motivated by sustainable development, the huge pressure of harmful dyes wastewater treatment has highlighted an urgent need to develop more effective biomass adsorbents for selective removal and separation of dyes. Herein, cellulose-based aerogel adsorbent (CPB) is successfully prepared through a novel crosslinking strategy for static and dynamic dye removal, starting with the fabrication of cellulose acetoacetate (CAA) and β-cyclodextrin acetoacetate (β-CDAA) through transesterification process, followed by the crosslinking of polymer chains using polyethyleneimine (PEI) through the formation of dynamic enamine bonds and the freeze-drying treatment of three-dimensional (3D) network structures. A maximum adsorption capacity toward methyl orange (MO) up to 1013.11 mg g−1 is achieved at 25 °C. Besides, the CPB aerogel has abundant surface positive charge, which can be employed to selectively remove anions dyes from ternary mixed systems and has additional antibacterial activity. More importantly, the CPB material based on the dynamic crosslinking strategy can be regulated by adjusting pH, which greatly facilitates the reprocessing and utilization of the adsorbent. The cellulose-based aerogel presented in this work could be an extremely promising material for dye wastewater treatment. [ABSTRACT FROM AUTHOR]

Nowadays, about 30% of food is damaged or wasted during the transport and preservation process. Therefore, there exists a big challenge to enhance the shelf-life and safety of perishable vegetables and fruits at a minimal cost. Herein, a highly scalable and innovative natural-derived bio-nanocomposites based on the available and low-cost materials (wood powder and wheat gluten) is designed for food preservation. Both the lignocellulose nanofibers (LCNF)-wheat gluten (WG) hybrid coatings on the surface of fruits and the hybrid packaging films show prominent preservation performance for six kinds of fruits with different respiratory metabolisms to prolong the shelf-life of fruits. The multifunctional LCNF-WG coating and packaging displayed excellent barrier properties to oxygen (15.9 cm3 μm m−2 day−1 kPa−1) and water vapour (10.3 g mm−1 m−2 day−1) and excellent antimicrobial, UV blocking, water-resistant, reusable and recoverability performance, making it a promising economic alternative in food preservation with the natural-derived material. Moreover, the low cost and degradation ability of this natural-derived bio-nanocomposite are beneficial for producers, consumers, and the environment. [Display omitted] • LCNF played an important role in the colloidal stability performance. • LCNF-WG coatings and films show prominent preservation performance. • LCNF-WG films displayed excellent barrier properties to oxygen and water vapour. • LCNF-WG films displayed excellent antimicrobial, UV blocking, reusable performance. [ABSTRACT FROM AUTHOR]

[Display omitted] • Phosphated lignocellulose nanofibrils were combined with MXene and gelatin; • The aerogel exhibited excellent fire retardancy with fire-warning performance; • Performance of electromagnetic interference shielding also achieved highly. Lightweight electromagnetic interference (EMI) shielding material with environment-friendly and high fire-safe has imperative practical significance in civil electronic devices. Herein, a distinct strategy was proposed to integrate phosphated lignocellulose nanofibrils (PLCNFs), gelatin, and MXene into a hybrid composite aerogel (PGM aerogel) with ultralight weight and high porosity. Due to the synergistic flame retardant effect of the ternary mixture, PGM aerogel exhibited excellent fire retardancy, whose dramatical changes in electronic resistance was supposed to achieve a short fire-warning signal (∼1 s). The limiting oxygen index (LOI) was as high as 32 % and the peak heat release rate (PHRR) was relatively as low as 30.1 W/g. Furthermore, the aerogel also displayed great specific EMI shielding effectiveness (SE) of SSE/t (14230 dB cm2 g−1) at 8.2 GHz. Therefore, this PGM aerogel can be a potential candidate in both EMI shielding and fire-warning fields. [ABSTRACT FROM AUTHOR]

Water-soluble cellulose ethers are widely used as stabilizers, thickeners, and viscosity modifiers in many industries. Understanding rheological behavior of the polymers is of great significance to the effective control of their applications. In this work, a series of cyanoethylcellulose (CEC) samples with different molecular weights were prepared with cellulose and acrylonitrile in NaOH/urea aqueous solution under the homogeneous reaction. The rheological properties of water-soluble CECs as a function of concentration and molecular weight were investigated using shear viscosity and dynamic rheological measurements. Viscoelastic behaviors have been successfully described by the Carreau model, the Ostwald-de-Waele equation, and the Cox–Merz rule. The entanglement concentrations were determined to be 0.6, 0.85, and 1.5 wt% for CEC-11, CEC-7, and CEC-3, respectively. All of the solutions exhibited viscous behavior rather than a clear sol-gel transition in all tested concentrations. The heterogeneous nature of CEC in an aqueous solution was determined from the Cox–Merz rule due to the coexistence of single chain complexes and aggregates. In addition, the CEC aqueous solutions showed good thermal and time stability, and the transition with temperature was reversible. [ABSTRACT FROM AUTHOR]