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Ternary nanocomposites including cellulose nanocrystals/silver nanohybrids (CNC-Ag) and biodegradable poly(3-hydroxybutyrate-co-3-hydroxyvalerate) (PHBV) were prepared by using solution casting. The effect of different AgNPs contents in the nanohybrids on crystallization ability and properties of PHBV was comprehensively investigated. Compared to binary PHBV/CNC nanocomposite, the ternary nanocomposites with high AgNPs contents showed larger improvements in the thermal stability, mechanical, barrier, overall migration and antibacterial properties. The property transitions at various AgNPs contents were due to transition of the nanohybrids induced PHBV crystallization ability (from single CNC nucleation to synergistic nucleation of CNC and AgNPs), and increased crystallinity without compromising the amounts of hydrogen bonds. Especially, the PHBV/CNC-Ag-1.7 showed the good barrier property and lower migration levels in food simulants, high antibacterial ratio of 99.9% and biocompatibility to human MG-63 cells, suggesting its potential application in food packaging related materials. [ABSTRACT FROM AUTHOR]

Fiber-based wearable electronic textiles have broad applications, but non-degradable substrates may contribute to electronic waste. The application of cellulose-based composite fibers as e-textiles is hindered by the lack of fast and effective preparation methods. Here, we fabricated polyaniline (PANI)/cellulose fibers (PC) with a unique skin-core structure through a wet-spinning homogeneous blended system. The conductive network formation was enabled at a mere 1 wt% PANI. Notably, PC15 (15 wt% PANI) shows higher electrical conductivity of 21.50 mS cm−1. Further, PC15 exhibits excellent ammonia sensing performance with a sensitivity of 2.49 %/ppm and a low limit of detection (LOD) of 0.6 ppm. Cellulose-based composite fibers in this work demonstrate good gas sensing and anti-static properties as potential devices for smart e-textiles. [Display omitted] [ABSTRACT FROM AUTHOR]

Highlights • A facile method of loading metal-organic frameworks (MOFs) onto cellulose aerogels (CA) is developed. • The equilibrium adsorption capacity of Pb2+ adsorbed by UiO-66-NH 2 @CA was 89.40 mg g−1. • The complete decomposition temperature of UiO-66-NH 2 @CA was increased by 62.1 ℃ compared with CA. • The hybrid aerogels could be recycled without secondary pollution. Abstract In the present work, we develop novel method of loading metal-organic frameworks (UiO-66 and UiO-66-NH 2) on the flexible cellulose aerogels as metal-organic frameworks@cellulose aerogels composite materials by using in situ growth procedure at room temperature. The as prepared metal-organic frameworks@cellulose aerogels composite materials were well characterized via SEM, XRD, atomic absorption spectrometer, and TG analysis, besides the adsorption of Pb2+ and Cu2+ in metal-organic frameworks@cellulose aerogels composite materials was investigated. The amount of metal ions adsorbed by metal-organic frameworks@cellulose aerogels composite materials is equal to the sum of metal-organic frameworks and cellulose aerogels, indicating that the metal-organic frameworks are not blocked after cellulose aerogels growth and still have adsorption properties. It was found that metal-organic frameworks@cellulose aerogels composite materials can be recycled to adsorb Pb2+ and Cu2+ in water after simple cleaning. The equilibrium adsorption capacity of Pb2+ adsorbed by UiO-66-NH 2 @CA was 89.40 mg g−1, and can be easily reused for more than 5 cycles without significant decrease in performance. Moreover, the maximum decomposition temperature (T max) of UiO-66-NH 2 @CA was increased by 62.1℃. This result suggested that such metal-organic frameworks@cellulose aerogels composite materials could adsorb heavy metal ions in water could by avoiding secondary pollution and show great potential in water treatment. [ABSTRACT FROM AUTHOR]

Fabrication and characterization of bbiodegradable nanocomposites based on poly (3-hydroxybutyrate- co -3-hydroxyvalerate) (PHBV) matrix reinforced with cellulose nanocrystal (CNC)-ZnO nanohybrids via simple solution casting for possible use as antibacterial biomedical materials is reported. The obtained nanocomposites exhibited an excellent antibacterial ratio of 95.2–100% for both types of bacteria namely S. aureus and E. coli and showed 9–15% degradation after one week. The addition of CNC-ZnO showed a positive effect on hydrophilicity and barrier properties. More significantly, the nanocomposites with 10 wt% CNC-ZnO showed enhancement in tensile strength (140.2%), Young’s modulus (183.1%), and the maximum decomposition temperature (T max ) value increased by 26.1 °C. Moreover, this study has provided a possible mechanism for using such nanofillers on the hydrolytic degradation of PHBV, which was beneficial to obtain the high-performance nanocomposites with modulated degradation rate for antibacterial biomaterials. [ABSTRACT FROM AUTHOR]

The development of sustainable, biodegradable, non-toxic biomass foams with outstanding physical properties to replace traditional petroleum-based foams is urgent. In this work, we proposed a simple, efficient, and scalable approach to fabricate nanocellulose (NC) interface enhanced all-cellulose foam through ethanol liquid phase exchange and subsequent ambient drying. In this process, NCs served as reinforcer and binder were integrated with pulp fiber to improve cellulose interfibrillar bonding and interface adhesion between NCs and pulp microfibrils. The resultant all-cellulose foam displayed stable microcellular structure (porosity of 91.7–94.5 %), low apparent density (0.08–0.12 g/cm3), and high compression modulus (0.49–2.96 MPa) by regulating the content and size of NCs. Further, the strengthening mechanism of the structure and property of all-cellulose foam were investigated in detail. This proposed process enabled ambient drying, and is simple and feasible for low-cost, practicable, and scalable production of biodegradable, green bio-based foam without special apparatuses and other chemicals. In this work, a simple, efficient and scalable approach was developed to fabricate lightweight, robust and biodegradable all-cellulose foam without special apparatuses and other chemicals. The incorporation of NCs improved cellulose interfibrillar bonding and interface adhesion between NCs and pulp microfibrils, and promoted the formation of stable 3D network structure resisting the increased capillary force in the ambient drainage process. The resultant all-cellulose foam displayed stable microcellular structure, low apparent density, and high compression modulus. [Display omitted] [ABSTRACT FROM AUTHOR]

Metal-organic frameworks (MOFs) and their derived powder catalysts are prone to agglomerate and difficult to recycle in water, thus resulting in their low utilization and secondary pollution in water treatment. Herein, a composite aerogel (CoFe0.8@NCNT@CA) loaded with bimetallic MOF-derived carbon nanotubes on cellulose aerogel was developed for activating peroxymonosulfate (PMS) to degrade tetracycline (TC). The CoFe0.8@NCNT@CA/PMS system exhibits an excellent TC removal rate (97.1 % TC removal within 20 min). The outstanding performance of the composite catalyst is closely related to the synergistic effect of bimetallic catalytic sites, graphitic N structure, and porous network. Interestingly, carbon nanotubes and cellulose in the composite catalyst form a semi-coated porous structure, which can effectively enhance the adhesion of carbon nanotubes and expose abundant active sites while ensuring mass transfer. This study provides a strategy for synthesizing novel composite aerogel with an excellent structure and physicochemical properties for water treatment. MOF-derived carbon nanotubes form a semi-encapsulated structure with the cellulose aerogel, catalytic metal sites are wrapped in carbon nanotubes. Tetracycline is degraded with CoFe0.8@NCNT@CA process through superoxide radical mechanism, hydroxyl radicals and sulfate radical co-oxidation mechanisms. [Display omitted] [ABSTRACT FROM AUTHOR]

The discharge of effluents from surfactant manufacturers is giving rise to increasingly serious environmental problems. In order to develop the eco-friendly flocculation materials to achieve effective removal of pollutants from the surfactant effluents, the bamboo pulp cellulose from Phyllostachys heterocycla is employed as the skeleton material to synthesize an eco-friendly bamboo pulp cellulose-g-polyacrylamide (BPC-g-PAM) for flocculation. The BPC-g-PAM is used with the metal ions as the coagulant to treat the effluent from a surfactant manufacturer. The response surface methodology coupled with Box–behnken design is employed to optimize the key factors of coagulation–flocculation. The results show that the combination of Fe 3+ with BPC-g-PAM achieves the best coagulation–flocculation performance like, the fast treatment time, minimum coagulant and BPC-g-PAM dosages compared with the other two combinations of Al 3+ with BPC-g-PAM and Ca 2+ with BPC-g-PAM. Therefore, the combination of Fe 3+ with BPC-g-PAM is expected to promote its application for the pollution control in the surfactant manufacturers. [ABSTRACT FROM AUTHOR]

Abstract: In order to develop an eco-friendly superabsorbent composite, flax yarn waste (FYW) was used as raw material to synthesize a novel flax yarn waste-g-poly(acrylic acid-co-acrylamide) (FYW/PAA) superabsorbent composite. Acrylic acid (AA) and acrylamide (AM) were grafted onto the pretreated flax yarn waste (PFYW) by free-radical graft copolymerization in homogeneous aqueous solution. The properties and synthesis conditions of the FYW/PAA superabsorbent composite were investigated. As a result, the prepared FYW/PAA attained the best water absorbency of 875g/g in distilled water, 490g/g in rainwater and 90g/g in 0.9wt% NaCl solution. The urea loading percentage of FYW/PAA could be modulated by the concentration of urea. The release of urea from FYW/PAA in water showed a typical three-stages sustained release behavior. Meanwhile, a weight residue of 53.6wt% was attained after being buried in soil for 90d. [Copyright &y& Elsevier]

Abstract: A new, low-cost, and eco-friendly cellulose-based superabsorbent was successfully prepared from flax yarn waste. The method used was a free-radical graft copolymerization of AA and AM onto a cellulose backbone in a homogeneous aqueous solution. APS was used as the initiator in the presence of a crosslinker, MBA. The effects of various factors on water absorbency were discussed. The factors included reaction temperature, initiator amount, monomer amount, salt solution type, and solution pH. Under the optimized conditions, the water absorbencies of the obtained superabsorbent composite were 875g/g distilled water, 490g/g natural rainwater, and 90g/g 0.9wt% aqueous NaCl solution. The product also had excellent water retention and salt resistance properties. Fourier-transform infrared spectroscopy and scanning electron microscopy were employed to examine the structure of the prepared superabsorbent. [Copyright &y& Elsevier]

Abstract: The paper reported a facile and green synthesis of silver nanoparticles by using hyaluronan (HA) as a reducing agent and soft template. The effect of reaction conditions on the Ag nanoparticle formation was investigated using UV–vis spectrophotometer, field-emission scanning electron microscopy, transmission electron microscopy and X-ray diffraction. The application of Ag nanoparticles in surface enhanced Raman scattering (SERS) of HA was also evaluated. The results showed that the high pH value, temperature and molar ratio of HA to AgNO3 could accelerate the reduction rate of Ag+ and affect the Ag nanoparticle size. The Ag nanoplates could be fabricated with a low molar ratio of HA to AgNO3 by aging, which may be due to the selective adsorption and desorption of HA on the different crystallographic planes of Ag nanoparticles. The enhancement of Raman scattering effect was greatly dependent on the size and morphology of Ag nanoparticles. [Copyright &y& Elsevier]

Abstract: A kind of cellulose whiskers were extracted from the branch-barks of mulberry (Morus alba L.) by an alkali treatment at 130°C and subsequently a sulfuric acid hydrolysis. AFM image showed that the diameter of obtained whiskers was ranged from 20 to 40nm. The chemical compositions analysis, FT-IR, XRD results indicated that the hemicellulose and lignin were removed extensively in the cellulose whiskers, with a crystallinity of 73.4%. The TGA curves implied a two-stage thermal decomposition behavior of cellulose whisker due to the introduction of sulfated groups into the crystals in the sulfuric acid hydrolysis process. The obtained whiskers may have the potential applications in the fields of composites as a reinforcing phase, as well as in pharmaceutical and optical industries as additives. [Copyright &y& Elsevier]

• Magnetic cellulose nanocrystals hybrids reinforced PCF composites were prepared. • Dipole responsive magnetic/solar driven thermal energy storage of PCF composites have reported. • PCF composite exhibited magnetic or solar thermal energy storage efficiencies of 32.1 and 58.6 %. • The PCF composites showed excellent thermal performance and shape stability. • The PCF composites can be used as an integrated collector for potential fruits dryer devices. The intrinsic intermittence of solar energy raises the necessity for thermal energy storage (TES) systems to balance the contradiction between energy supply and demand energy. This work experimentally provides solid-liquid phase change materials (PCMs) with sufficient storage capacity and discharging rate to offer heating for agriculture products by enhancing heat transfer in phase change fiber composites (PCF). To achieve this, we prepared dipole responsive magnetic/solar-driven PCF composites reinforced with magnetic cellulose nanocrystals hybrids (M CNC). The obtained PCF/ M CNC-5% showed excellent magnetic property with a saturation magnetization (MS) value of 1.3 emu/g and effective latent heat phase change enthalpies of 69.2 ± 3.5 J/g – 83.1 ± 4.2 J/g. More importantly, PCF/ M CNC-5% showed robust high magnetic to thermal energy storage efficiency of 32.5 % and solar light accelerated energy storage efficiency of 58.5 %. These advantages make the PCF composites promising and more desirable for drying and preservation of the fruits and other agriculture products. [ABSTRACT FROM AUTHOR]

• Synthesis of bimetallic silver-gold NPs was realized in a cellulose dope. • The dissolved cellulose played as reductant and support matrix for the NPs. • Structure of the NPs was facially tuned by adjusting the feeding operations. • Correlation of bioactivity with nanostructure of the NPs was investigated. • Flexible cellulose decorated with the NPs endowed its efficient SERS activity. Introducing functional metal nanoparticles (NPs) into flexible substrate is being increasingly attempted to expand their application. Here, we extend the synthesis of cellulose to its unmodified dope achieving freestanding nanocomposite decorated with bimetallic Ag-Au NPs through the one pot reaction. In the procedure, cellulose chain not only acts as a reducing agent but also a biocompatible support for NPs with a mean size of 7.9–9.7 nm. Meanwhile, changing the addition order of Ag+ and AuCl 4 − generated different atom arrangement in the bimetallic NPs. Moreover, the correlation of bioactivity to NP atom arrangement was studied. The result revealed that the nanocomposite containing NPs with an ultrathin Ag-rich outermost shell around an Au-rich core showed better bactericidal ability while lower cytotoxicity. In addition, the nanocomposite exhibited a sensitive SERS property for determination of R6G with a high enhancement factor of 108. [ABSTRACT FROM AUTHOR]