Nanofibrillated celluloses (NFCs) have recently drawn much attention because of their exceptional physicochemical properties. However, the existing preparation procedures either produce low yields or severely degrade the cellulose and, moreover, are not energy efficient. The purpose of this study was to develop a novel process using ultrasonic homogenization to isolate fibrils from bamboo fiber (BF) with the assistance of negatively charged entities. The obtained samples were characterized by the degree of substitution (DS) of carboxymethyl, Fourier-transform infrared (FT-IR) spectroscopy, X-ray diffraction (XRD), thermogravimetric analysis, and transmission electron microscopy (TEM). The results showed that an NFC yield could be obtained above 70% through this route. The enzyme hydrolysis could enhance the surface charge of the fiber, and mechanical activation facilitates an increase in the DS. The disintegrating efficiency of the cellulose fibrils significantly depended on the input power of ultrasonication and the DS. FT-IR spectra confirmed the occurrence of the carboxymethylation reaction based on the appearance of the characteristic signal for the carboxyl group. From XRD analysis, it was observed that the presence of the carboxyl groups makes the isolation more efficient attributed to the ionic repulsion between the carboxylate groups of the cellulose chains.

The freshness and safety of fruits and vegetables is important in our daily life. Paper products are often used for shipping, wrapping, and decoration in the retail for fruits and vegetables. When these paper products are modified with active substances, they can offer additional functions other than just packaging. Thus, introducing 1-methylcyclopropene (1-MCP) into paper products can impart a preservation function for fruits and vegetables. 1-MCP is an excellent and eco-friendly inhibitor of ethylene that can effectively retard the ripening of fruits and vegetables. This article reviews the ripening process induced by ethylene, the inhibition mechanism of 1-MCP, and the existing technologies and products for 1-MCP utilization. Novel active paper packaging products via the use of encapsulated 1-MCP complexes may have a great potential for commercialization. Such packaging containing 1-MCP active paper could be effective in prolonging the shelf-life and improving the quality of the product during the storage, shipping process, and retail market, and can be attractive economically, socially, and environmentally.

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Short carbon fibers (SCF) were modified with oxidation and coupling treatment to improve their water-wettability and bonding properties. Four types of dispersants were studied and discussed. Short carbon fibers/plant fiber (PF) composite papers were prepared by papermaking techniques. Scanning electron microscopy (SEM) and tests to determine zeta potential, absorbance, tensile index, and conductivity were carried out to investigate the modified effect of SCF and the interfacial properties. Modification experimental results showed that the surface grooves were deepened and new superficial grooves were generated by the liquid acid oxidation. The reaction with the silane coupling agent provided higher density and more uniform distribution on the SCF surface than that of organic titanate, and it obviously increased the roughness and the absolute value of zeta potential. After modification, the hydrophilic properties and dispersion in aqueous solutions were improved, the SCFs could form a good mechanical grip with plant fibers, and the conductivity and physical strength of SCF/PF composite papers were enhanced. It was shown that there was obvious adhesive binding at the fiber overlap nodes by the SEM analysis. It was confirmed that the improvement of physical properties of composite paper can be ascribed to the interfacial enhancement.