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In this study, hyperthermal hydrogen-induced cross-linking (HHIC) technology was applied to construct a dense cross-linking layer of antibacterial chitosan quaternary ammonium salt (HTCC) to PE surface through the selective cleavage of CH bonds and subsequent cross-linking of the resulting carbon radicals. Before HHIC treatment, UV-Ozone was used to activate PE surface to facilitate HTCC adsorption. FT-IR and XPS analyses proved the successful cross-linking between PE and HTCC. From AFM analysis, the prepared PE cross-linked HTCC film (PE-c-HTCC) showed the rougher surface with average roughness (Ra) of 9.16 nm. The water vapor permeability (WVP) and oxygen permeability (OP) values of the film were decreased by about 83 % and 97 %, respectively. Additionally, the film exhibited strong antibacterial properties against E. coli and S. aureus. In terms of these properties, the shelf life of fresh beef could be extended for 2 days after packing with the PE-c-HTCC film., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2024 Elsevier B.V. All rights reserved.)

Selective fractionation of hemicelluloses is of great significance for realizing high-value application of hemicelluloses and comprehensive utilization of lignocellulosic biomass. Tetramethylammonium hydroxide (TMAH) solvent has been confirmed as a promising solvent to selectively fractionate hemicelluloses from holocellulose. Herein, TMAH solvent was adopted to pretreat poplar thermomechanical pulp (PTMP) for the selective fractionation of hemicelluloses and enhancement of enzymatic hydrolysis performance of residues. The maximal hemicelluloses yield (65.0 %) and excellent cellulose retention rate (93.3 %) were achieved after pretreatment by the 25 wt% TMAH solvent, while the delignification was only 33.9 %. The hemicelluloses fractions could be selectively fractionated with high molecular weights (109,800-118,500 g/mol), the contents of Klason lignin in them were low (3.2-5.9 %), and the dominating structure of them was 4-O-methylglucurono-β-D-xylan. Compared to the H 2 SO 4 and NaOH methods, the hemicelluloses fractionated by TMAH method exhibited higher yields, more complete structures and higher molecular weights. Furthermore, the crystalline structure of cellulose practically remained stable, and the highest yield of enzymatic hydrolysis glucose was 57.5 %, which was 3.3 times of that of PTMP. The fractionation effectiveness of TMAH solvent was not significantly reduced after repeatedly recycling. This work demonstrated TMAH solvent could selectively fractionate hemicelluloses from PTMP and efficiently promote sustainable poplar-based biorefinery., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2023 Elsevier B.V. All rights reserved.)