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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]

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]

• 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]