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Highlights • [Amim][Cl] and [Bmim][Cl] was more suitable for preparing quality film. • A decrease of DP resulted in a higher crystallinity index. • Crystal structure governs the properties of the film. Abstract Three ionic liquids (ILs) with increasing dissolution power, 1-butyl-3-methylimidazolium chloride ([Bmim][Cl]), 1-allyl-3-methylimidazolium chloride ([Amim][Cl]), and 1-ethyl-3-methylimidazolium acetate ([Emim][Ac]), were selected for cellulose dissolution and film preparation through regeneration. The physical properties of the films were investigated, and the correlation between the IL used and the film properties was evaluated. The results indicated that the superior cellulose dissolution system, [Emim][Ac], had the most difficult regeneration process (i.e., more time was required for gel formation), followed by [Amim][Cl], and [Bmim][Cl]. On the other hand, the film produced from [Amim][Cl] had the highest crystallinity, transparency, and tensile strength, followed by the films produced from [Bmim][Cl] and [Emim][Ac]. It was inferred that stronger and more ordered molecular arrangements and inter-molecular interactions preferentially occurred during cellulose regeneration from [Amim][Cl] than during cellulose regeneration from [Bmim][Cl] and [Emim][Ac]. [ABSTRACT FROM AUTHOR]

Robust superhydrophobic and superoleophilic cellulose- g -PFOEMA filter paper membranes were fabricated via surface grafting of poly(perfluorooctylethyl methacrylate) (PFOEMA) using atom transfer radical polymerization (ATRP). The surface chemical compositions, morphologies and wettability of cellulose- g -PFOEMA with different degree of graft ratio (DG) were investigated using attenuated total reflectance Fourier transform infrared spectroscopy (ATR-FTIR), X-ray photoelectron spectroscopy (XPS), scanning electron microscope (SEM), and contact angle (CA) measurement. IR and XPS showed that PFOEMA were introduced into surface of filter paper. The superhydrophobicity of filter paper increased with amount of PFOEMA grafted. When DG of grafted PFOEMA was higher than 11.2%, the superhydrophobicity reached a steady state and the measured water contact angle was about 157°. The PFOEMA-grafted filter paper exhibited excellent chemical resistance toward a wide range of pH solution from 1 to 12. Cellulose- g -PFOEMA is convenient for oil/water separation with efficiency higher than 95%. The excellent reusability and stability make cellulose- g -PFOEMA filter paper membrane a promising candidate in the applications of oil spillage cleanup and the separation of oil/water mixture. [ABSTRACT FROM AUTHOR]

Highlights: [•] Carboxymethyl cellulose (CMC) was oxidized to form dialdehyde CMC (DCMC). [•] Guanidine hydrochloride (GH) was grafted onto the DCMC to obtain DCMC-GH. [•] The coating of DCMC-GH onto paper resulted in the improvement of paper strength. [•] The DCMC-GH-coated paper exhibited excellent antimicrobial activities. [Copyright &y& Elsevier]

• LBL-NF-CS/BCM were prepared by combining layer-by-layer assembly with spraying. • Chitosan was added to a cellulose casting solution to gain positive cationic charge. • LBL-NF-CS/BCM exhibited excellent NCl filtration performance at ultra-low pressure. Cellulose is a renewable, biodegradable, biocompatible, and sustainable material. A bamboo cellulose-based nanofiltration membrane (LBL-NF-CS/BCM) was prepared with a combination of layer-by-layer assembly and spraying methods. The chemical structure, morphology, and surface charge of the resultant LBL-NF-CS/BCM composite membranes were characterized based on Thermo Gravimetric Analysis (TGA), X-ray diffraction (XRD), Scanning Electron Microscopy (SEM), Atomic Force Microscopy (AFM), and X-ray Photoelectron Spectroscopy Scanning (XPS). The nanofiltration performance of the LBL-NF-CS/BCM composite membranes was evaluated using 500 ppm NaCl solutions under 0.3 MPa pressure. It was found that the LBL-NF-CS/BCM composite membranes had a rejection rate of about 36.11 % against a 500 ppm NaCl solution under the conditions tested, and membrane flux of about 12.08 L/(m2 h) was reached. The combined layer-by-layer assembly and spraying provides a scalable and convenient process concept for nanofiltration membrane fabrication. [ABSTRACT FROM AUTHOR]