Using xylan as a compatibilizer to enhance the compatibility of cellulose and lignin coatings in order to improve the wet-low-temperature properties of coated paper after high-temperature aging

Cellulose is highly susceptible to adverse effects under wet-low-temperature, and high-temperature conditions, leading to a significant decline in performance. This study employs xylan as a compatibilizer to co-dissolve cellulose/lignin/xylan in an ionic liquid, forming a composite coating on filter paper through hot-press infiltration. The experimental results demonstrate that the composite coated paper fabricated using this approach exhibits superior mechanical properties, with dry and wet tensile strengths of 50.75 MPa and 15.20 MPa, respectively, compared to those of untreated filter paper (18.66 MPa and <2 MPa). Additionally, the water absorption rate and water vapor transmission rate decreased significantly, from 219.92 % and 670.14 m 2  g −1 to 83.40 % and 172.96 m 2  g −1 , respectively. The mechanism behind the enhanced wet-low-temperature strength of composite-coated paper after high-temperature aging was also investigated. Results demonstrate that compared to the coated paper without lignin/xylan additives, which exhibited wet-low-temperature tensile strengths of 2.92 MPa, the lignin/xylan-added coated paper maintained tensile strengths of 8.26 MPa under similar conditions. Furthermore, the presence of lignin/xylan significantly mitigates the formation of pores and cracks in the coated paper after high-temperature aging. This study provides a novel approach and theoretical guidance for utilizing wood fiber materials in extreme packaging environments.