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Natural antioxidants are beneficial additives for active packaging due to their ability to resist oxidative damage. Polymeric micelles are effective in delivering natural antioxidants in aqueous environments. However, individual encapsulation of a single antioxidant may not be sufficient to meet the needs of modern food packaging. A dual natural antioxidant‐loaded micellar system (i.e., vitamin E [VE] and curcumin [Cur]) was developed to achieve combined functionality and high loading concentration. Chitosan‐graft‐oleic acid (CSOA) micelles were employed as carriers to co‐encapsulate VE and Cur through a facile ultrasound‐assisted self‐assembly method. The prepared VE and Cur co‐loaded micelles (CSOA/VE/Cur) exhibited a uniform spherical structure with an average particle size of 210.6 nm and a zeta potential of +29.5 mV. Moreover, the co‐encapsulation of VE and Cur showed a significant enhancement in both entrapment efficiency, loading capacity and stability as compared to the individual encapsulation of either VE or Cur. In addition, the CSOA/VE/Cur micelles showed improved antioxidant activity than free VE/Cur at the same concentrations, as evidenced by 2,2‐diphenyl‐1‐picrylhydrazyl (DPPH) and ferric reducing antioxidant power (FRAP) assays. Moreover, the micellar materials were utilized to fabricate regenerated cellulose (RC) films with antioxidant properties, highlighting their potential as additives for antioxidant active packaging. [ABSTRACT FROM AUTHOR]

Cellulose is a promising feedstock for the production of sustainable materials. To fully utilize its potential, exploring efficient cellulose solvents is a paramount prerequisite. In this study, ten superbase amino acid ionic liquids (SAAILs) are synthesized using 1,5‐diazabicyclo[4.3.0]non‐5‐ene (DBN) and 1,8‐diazabicyclo[5.4.0]undec‐7‐ene (DBU) with different amino acid anions via a simple neutralization method. The properties of these SAAILs, such as viscosity and glass transition temperature, varied with their cation and anion structures. The ability of the SAAILs to dissolve cellulose is related to their Kamlet–Taft parameters, particularly hydrogen bond basicity (β). The main driving force for cellulose dissolution in SAAILs is thought to be hydrogen bonding interactions between SAAILs and cellulose hydroxyl groups. Four SAAILs composed of DBN or DBU cations and proline, or aspartic acid anions are identified as promising solvents for preparing regenerated cellulose films (RCFs). The RCF prepared from [DBN]Proline(Pro) showed a favorable combination of high tensile strength (76.9 MPa), high Young's modulus (5201.2 MPa), good transparency (≈70% at 550 nm), and smooth surface morphology. These halogen‐ and metal‐free SAAILs show the potential to provide a new avenue for cellulose processing. [ABSTRACT FROM AUTHOR]

Herein, a novel, facile, and versatile approach to fabricate highly flexible and conductive paper is proposed by electroless deposition (ELD) with the assistance of aminocellulose as the interface layer. The obtained Cu nanoparticles (NPs)‐coated cellulose paper is highly conductive with a significant low resistance of 0.38 Ω sq−1 after only 10 min of ELD treatment. This conductive cellulose paper shows excellent stability when it suffers from bending, folding, and tape adhesion cycles. With the same method, the Cu NPs can also be successfully deposited on the polypropylene (PP)‐filled hybrid paper. The conductive paper exhibits very smooth and hydrophobic surface with high reflection, which can be used for special electronic devices. In a word, the fabrication of aminocellulose interface permits a controlled ELD of metal nanoparticles on paper substrate, and this mild and low‐cost method opens up new opportunities for large‐scale production of flexible and wearable electronics. [ABSTRACT FROM AUTHOR]

Novel cellulose nanomicelles self-assembled from amphiphilic cellulose-graft-poly( p-dioxanone) (MCC- graft-PPDO) copolymer were used to encapsulate and disperse hydrophobic fluorescent conjugated polymers (FCPs) in water for tumor cell imaging. Three different conjugated polymers were employed to demonstrate the versatility of the cellulose nanomicelles, resulting in highly fluorescent and stable polymeric nanoparticles with different emission wavelengths across the visible spectrum. Owing to the size effect of cellulose nanomicelles, the incorporated conjugated polymers present red-shifted emission to low-energy sites, and the fluorescence self-quenching of conjugated polymers at high concentration can be greatly inhibited. The in vitro studies using the liver cancer Hep3B cells and the breast cancer MAD-MB-231 cells indicate these amphiphilic cellulose/FCPs nanomicelles have negligible cytotoxicity even at high concentration of up to 100 μg/mL. Moreover, the light-emitting micelles are successfully uptaken by the cancer cells and located at the cytoplasm of the cells, suggesting their great potential for tumor cell imaging and early detection of tumor cells. [ABSTRACT FROM AUTHOR]

In response to the shortage of petroleum resources and the growing need for sustainable development, cellulose-based amphiphilic copolymers have emerged as a new generation of value-added functional nanostructures from biomass resources. In this article, 17 amphiphilic hydroxyethyl cellulose-based graft copolymers with different side chains, including poly(lactide), poly( ε-caprolactone) and poly( p-dioxanone), were synthesized via homogeneous ring opening polymerization in ionic liquid 1-butyl-3-methylimidazolium chloride and characterized by FT-IR, H NMR, thermogravimetric analysis and gel permeation chromatography. The resultant copolymers can self-assemble into micelles with a low critical micelle concentration that varies in the range of 0.03-0.24 mg/ml. TEM observations revealed the obtained micelles had a spherical and well-distributed morphology, and DLS analysis showed the nanoscaled sizes were between 40 and 150 nm. These HEC-based micelles can be used as nano-sized vesicles and have great latent forces in drug delivery systems. [ABSTRACT FROM AUTHOR]