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The harms caused by ultraviolet (UV) and blue light to eyes are attracting momentous concern due to growing exposure to artificial illumination and modern IT devices. Herein, a simple and eco-friendly adsorption approach was employed to integrate curcumin, a natural bioactive compound, into the cellulose substrate for the development of flexible and biodegradable filters capable of blocking harmful light. The curcumin/cellulose films demonstrate excellent UV-screening competence and photostability, with UV-A and UV-B screening ratios ranging from 92.8 % to 100 % and 89.2 % to 100 %, respectively. The films could block >96 % of blue light in the wavelength range of 400-500 nm. Meanwhile, the films maintain high transmittance (85.2-89.4 %) and low haze (2.0-2.7 %). The films can efficiently block blue light emanated from sunlight, light-emitting diodes, lighting systems, computer and mobile phone screens. Encouragingly, the incorporation of curcumin led to a substantial increase in the water contact angle, elevating it from 41.6 to 81.3°. Furthermore, the films exhibit excellent antimicrobial properties, biodegradability, and tensile strength in excess of 72 MPa. Therefore, these films fabricated entirely from natural resources have the potential to achieve practical applications such as food packaging and spectacle lens, especially suitable for electronic screen protectors., 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.)

Cellulose fibers(CFs)-based electrode materials are of considerable interest for future wearable electronic devices due to excellent flexibility and strength, and hydrophilicity. The effective introduction of electrode materials into CFs is essential for flexible supercapaciotors(SCs). A tunable electrochemical performance of conductive polymers for poly(3,4-ethylenedioxythiophene)(PEDOT) has been aroused great interests. Herein, we design its electrochemical process via sodium anthraquinone-2-sulfonate(AQS) as dopant and electrolyte additive to construct active electrode interior and interface. As a result, the PEDOT@CFs electrode exhibits great increase of doping level from 0.16 to 0.29, conductivity from 353.46 to 626.15 S m -1 , and specific capacitance from 140.22 to 1211.57 F g -1 at a current density of 0.2 A g -1 . Furthermore, the PEDOT:AQS@CFs electrode possess excellent cyclic stability (96.01 %) after 1000 cycles. The work reveals the mechanism of AQS as dopant and electrolyte additive, and provides a new perspective for application of PEDOT in energy storage field., 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 Elsevier B.V. All rights reserved.)

The demand for paper-based packaging materials as an alternative to incumbent disposable petroleum-derived polymers for food packaging applications is ever-growing. However, typical paper-based formats are not suitable for use in unconventional applications due to inherent limitations (e.g., excessive hydrophilicity, lack antimicrobial ability), and accordingly, enabling new capabilities is necessity. Herein, a simple and environmentally friendly strategy was proposed to introduce antimicrobial and hydrophobic functions to cellulose paper through successive chemical grafting of 3-aminopropyltriethoxysilane (APS) and cinnamaldehyde (CA). The results revealed that cellulose paper not only showed long-term antibacterial effect on different bacteria, but also inhibited a wide range of fungi. Encouragingly, the modified paper, which is fluorine-free, displays a high contact angle of 119.7°. Thus, even in the wet state, the modified paper can still maintain good mechanical strength. Meanwhile, the multifunctional composite papers have excellent biocompatibility and biodegradability. Compared with ordinary cellulose paper, multifunctional composite paper can effectively prolong the shelf life of strawberries. Therefore, the multifunctional composite paper represents good application potential as a fruit packaging material., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests., (Copyright © 2024 Elsevier B.V. All rights reserved.)

The combination of two or more seemingly different features into a unique composite is an exciting direction for the preparation of novel versatile materials. Here, we report a facile and green strategy to fabricate transparent multifunctional cellulose-based film material. With carboxymethylated cellulose hydrogel as supporting medium and carboxyl groups as reactive sites, a type of antibacterial, biodegradable and UV-blocking nanocomposite films were fabricated by in situ synthesis of copper(II)-imidazolate metal–organic framework (Cu-MOF). The results show that the nanocomposite films possessed remarkable UV-blocking capability through the whole UV region meanwhile retaining high transmittance. Due to the weak photocatalytic effect of Cu-MOF, the nanocomposite films exhibit high photostability even after continuous UV irradiation (365 nm) for 12 h while maintaining their good mechanical strength. Quite encouragingly, Cu-MOF endowed the film with desirable antibacterial ability, and the antibacterial mechanism could be explained by the release of metal ions and ligands from Cu-MOF. Moreover, the incorporation of Cu-MOF can enhance the mechanical strength of the nanocomposite films. Therefore, the nanocomposite films have great potential for UV protection and transparent antimicrobial packaging applications. [ABSTRACT FROM AUTHOR]

While tremendous efforts have been dedicated to developing cellulose-based ultraviolet (UV)-blocking films, challenges still remain in simultaneously achieving high transparency, low haze and excellent UV shielding properties via simple and green strategy. Here, we present a facile and eco-friendly route to fabricate flexible, biodegradable and clear UV-shielding nano-MIL-88A(Fe)@carboxymethylated cellulose films (M(Fe)CCFs) via in situ synthesis of nano-MIL-88A(Fe) in carboxymethylated cellulose hydrogel followed by natural drying. The carboxymethylated cellulose film has high transmittance (93.2%) and low haze (1.8%). The introduction of nano-MIL-88A(Fe) endowed M(Fe)CCFs superior UV-shielding ability, while retaining high transmittance (81.5–85.3%) and low haze (2.5–4.9%). Moreover, M(Fe)CCFs showed stable UV blocking performance under UV irradiation, high temperature, acidic or alkaline conditions. Quite encouragingly, the UV-shielding ability of M(Fe)CCFs did not deteriorate, even after 30 days of immersion in aqueous solution, providing films with a long-term use capacity. Thus, M(Fe)CCFs show high potential in the UV protection field. Overall, these UV-blocking films with outstanding performances are a promising candidate to replace conventional film materials made from synthetic polymers in fields such as packaging and flexible electronics. [ABSTRACT FROM AUTHOR]

Cellulose-based bioplastics with degradability and remarkable mechanical performance have recently attracted increasing attention. As a high-performance material, cellulose-based bioplastics have a strong potential to replace synthetic plastic substrates in many applications. However, its poor shielding performance to UV light limit its application. In this work, transparent and UV-blocking MIL-68(In)-NH2@cellulose bioplastic (M(In)CBP) sheets are fabricated via a featured processing method, i.e., cellulose liquefaction, rapid solidification, in-situ synthesis and hot-press drying. The as-obtained functional bioplastic sheet (M(In)CBP1) exhibits high visible-light transparence (74.7% a 600 nm) and the existence of MIL-68(In)-NH2 allows superior UV-blocking ability (below 400 nm, transmittance was under 4%). The M(In)CBP sheets show high photostability even after continuous UV irradiation (365 nm) for over 12 h. The superior UV-shielding performance is attributed to the uniform distribution and the high UV absorbance of MIL-68(In)-NH2 in M(In)CBP sheets. High resistance to penetration by aqueous/nonaqueous liquids was proved. Moreover, the M(In)CBP sheets also show excellent mechanical properties and thermal stability. The present work designed a UV-blocking bioplastic constructed from cellulose and MIL-68(In)-NH2, which is potential candidates to replace synthetic plastics in many advanced applications such as a UV protection layer for electronic products, or useful as packaging materials to prevent food spoilage. [ABSTRACT FROM AUTHOR]

Herein, we introduce antimicrobial activity to cellulose fibers (CFs) by presenting a double "click chemistry" strategy. CFs chemically modified with azide functions are designed as a versatile ligation platform for Cu(I)-catalyzed azide-alkyne click reaction. Glycidyl propargyl ether (GPE) with epoxy groups was grafted onto azidated cellulose fibers (CFs-N3) via azide-alkyne click reaction yielding epoxy cellulose fibers (CFs-Epoxy). Then poly(hexamethylene guanidine) (PHMG) can be chemically grafted onto the CFs to form antibacterial materials (CFs-PHMG) through amino groups initiated epoxy ring-opening click reaction. The results revealed that PHMG was anchored successfully onto CFs via chemical bond formation without significant damage to the morphology of CFs and mechanical performance of cellulose paper. In the antibacterial tests, the functionalized CFs show superior antibacterial activity against E. coli and S. aureus. Importantly, CFs-PHMG paper sheet presented long-term antibacterial effectiveness, remaining ~ 99% antibacterial activity after two months storage in the air environment. This antibacterial CFs-PHMG has good potential application in bioactive paper packaging and medical paper products. [ABSTRACT FROM AUTHOR]

In the current study, we introduce "click chemistry" as a powerful tool to tailor cyclodextrin–cellulose combination product followed by the inclusion of ciprofloxacin hydrochloride (CipHCl) as antibacterial agent. Initially, beta-cyclodextrin (β-CD) and cellulose fibers (CFs) were modified so as to be mono-6-propargylamino-6-deoxy-β-CD (Pro-β-CD) and azidated cellulose fibers (CFs-N3), respectively. Afterward, the "click reaction" was carried out between Pro-β-CD and CFs-N3 to fabricate a covalent grafting of β-CD onto CFs resulting in click product (CFs-N3@Pro-β-CD). The drug-delivery kinetics of the loaded CipHCl was performed by immersing samples into an aqueous solution, and the amount of adsorbed and released CipHCl was measured, as a function of time, by UV spectroscopy. Compared to original CFs, the load quantity of CipHCl into the click product was greatly increased, the release time of CipHCl from CFs-N3@Pro-β-CD was prolonged, and considerably higher antibacterial activity against E. coli and S. aureus was observed. The click product exhibited excellent antibacterial activity and sustained antibacterial efficacy up to 12 and 10 days against S. aureus and E. coli. The results showed that β-CD has been successfully grafted onto CFs via covalent bonds, while maintaining the intrinsic properties and the integrity of the fibers. Compared with the control paper sheet, the mechanical properties of the paper are well preserved. [ABSTRACT FROM AUTHOR]

Abstract: An efficient and simple way to generate "clickable" cellulose modules called alkyne-functionalized cellulose fibers (ACFs) for click reaction was presented. This method is only based on one step reaction: propargyl methacrylate (PMA) with pendant alkynyl groups was grafted onto the surface of cellulose fibers (CFs) using ceric ammonium nitrate as the initiator in aqueous medium. This has been providing a new and versatile platform for the wide utilization of cellulose resources and creation of novel functional materials. The effect of process variables on grafting copolymerization of PMA was investigated and suitable preparation conditions were identified. The clickability of ACFs was evaluated by reacting with two azides. The antibacterial cellulose functional material was achieved through incorporation of a "clickable" handle (alkynyl groups) to cellulose fibers followed by rapid attachment of β-cyclodextrin with an azide tag using copper-catalyzed click reaction and loading with ciprofloxacin hydrochloride (CipHCl). Pure CFs and ACFs showed a little affinity to CipHCl, whereas click products (ACFs@Azide-β-CD) increased the loading amount dramatically because the equilibrium amount was higher than pure CFs and ACFs. Meanwhile, the release process of CipHCl from ACFs@Azide-β-CD was prolonged to reaches the equilibrium. The ACFs@Azide-β-CD loaded with CipHCl showed excellent antibacterial activity against Escherichia coli. The ACFs@Azide-β-CD loading CipHCl have considerably longer bacterial activity against E. coli compared to CFs and ACFs.Graphical abstract: [ABSTRACT FROM AUTHOR]

It is still a challenge to realize super clear cellulose-based film materials with different functional combinations. This study presents a novel concept of fabricating flame-retardant, mechanically strong, UV and blue light double-blocking carboxymethylated cellulose-based nanocomposite bioplastics enabled by nano-metal organic framework (MIL-125(Ti)-NH 2). Carboxymethylated cellulose gel with porous structure acts as nanoreactor and carboxyl groups as reactive sites to facilitate the growth and anchorage of nano-MIL-125(Ti)-NH 2. Super clear bioplastics were obtained through hot-pressing. The results show that the neat carboxymethylated cellulose bioplastic possesses high transmittance (94.1% at 600 nm) and low haze (2.0% at 600 nm). The incorporation of nano-MIL-125(Ti)-NH 2 enabled nanocomposite bioplastics to obtain UV and blue light double-shielding capability meanwhile retaining high transmittance (79–92.8%) and low haze (2.6–7.2%). Moreover, the incorporation of nano-MIL-125(Ti)-NH 2 was found to significantly improve the mechanical strength and decrease the flammability of nanocomposite bioplastics. This facile strategy would direct nanocomposite bioplastics toward diversified applications. • Nano-MIL-125(Ti)-NH 2 -embedded nanocomposite bioplastics were prepared. • Nanocomposite bioplastics showed UV and blue light double-blocking capacity. • Nanocomposite bioplastics exhibited high optical transmittance and low haze. • Nano-MIL-125(Ti)-NH 2 improved tensile strength and flame retardant of bioplastics. [ABSTRACT FROM AUTHOR]

The development of photothermal materials with a high light-to-heat conversion capability is essential for the utilization of clean solar energy. In this work, we demonstrate the use of a novel and sustainable concept involving cellulose liquefaction, rapid gelation, in situ synthesis and hot-press drying to convert cellulose and metal–organic framework (Prussian blue) into a stable photothermal bioplastic that can harvest sunlight and convert it into mechanical motion. As expected, the obtained Prussian blue@cellulose bioplastic (PCBP) can effectively absorb sunlight and the surface can be heated up to 70.3 °C under one sun irradiation (100 mW cm−2). As a demonstration of the practicality of PCBP, it was successfully used to drive a Stirling engine motion. Meanwhile, hot-pressing promotes the densification of the structure of PCBP and, therefore, improves the resistance to the penetration of water/non-aqueous liquids. Moreover, PCBP shows good mechanical properties and thermal stability. Given the excellent photothermal performance and environmentally friendly features of photothermal conversion bioplastic, we envisage this sustainable plastic film could play important roles toward diversified applications: a photothermal layer for thermoelectric generator, agricultural films for soil mulching and photothermal antibacterial activity, among others. [ABSTRACT FROM AUTHOR]

Anti-blue light films with high transparency and low haze that completely originate from renewable and biodegradable biomass materials for eye protection is a growing trend with great demand in the near future. Therefore, in this study, a natural bioactive ingredient, lutein, was incorporated into the cellulose matrix via a green and facile adsorption strategy to prepare biodegradable ultraviolet (UV) and blue light filters. The lutein/carboxymethylated cellulose films (L-CCFs) displayed high anti-UV capacity, with UV-A and UV-B blocking ratios of 52.7 %-90.9 % and 44.1–85.2 %, respectively. The composite films could block 83.1–97.8 % of blue light in the 400−500 nm region while maintaining high transparency (86.6–89.3 %) and low haze (2.1–2.6 %). By light absorption, the films can effectively shield blue light emitted by light-emitting diodes, sunshine, lighting systems, mobile phone, and computer screens. Quite encouragingly, the addition of lutein significantly increased the water contact angle from 40.1 to 70.5° and the composite films have excellent liquid barrier properties. Meanwhile, these films exhibit higher light stability than lutein powders, thus greatly extending the service life of the film as a blue light shielding material. Moreover, the films have excellent mechanical strength (>110 MPa) and biodegradability. These films prepared entirely from natural resources offer great application value in the fields of electronic screen films and spectacle lenses. [Display omitted] • High tensile strength lutein-cellulose films were prepared for eye protection. • Lutein-cellulose films demonstrated UV and blue light double-blocking capacity. • Lutein-cellulose films exhibited high optical transmittance and low haze. • Compositing with lutein could improve water contact angle of films. [ABSTRACT FROM AUTHOR]