Improvement of paper moisture permeability with hydrophobic modified nanocellulose/poly (lactic acid) composites

Polylactic acid (PLA) and nanocellulose fibers (CNF) are promising biodegradable materials that exhibit great potential in healthcare and packaging applications. In this study, dissolved CNF (DMCNF) was obtained through the AlCl ₃ /ZnCl ₂ solution system and subsequently grafted with γ-methylacryloxy propyl trimethoxy-silane (KH-570), and PLA/DMCNF coated paper was fabricated by the coating process. Scanning electron microscopy (SEM), infrared spectroscopy (FT-IR), X-ray photoelectron spectroscopy (XPS), X-ray diffraction (XRD), thermal analysis, water permeability, water contact angle, and tensile testing were employed to characterize the prepared coated paper. The results indicate that the dissolution of AlCl ₃ /ZnCl ₂ can significantly facilitate the modification of CNF, and the addition of DMCNF has a crucial impact on the overall properties of polylactic acid coated paper. The increase of DMCNF can enhance the moisture permeability, hydrophobicity, and tensile properties of PLA-based coated paper. Notably, the moisture permeability of PLA/DMCNF coated paper was reduced by 72.6% compared to the base paper. Therefore, this research provides an effective approach for the enhancement of PLA-based coated paper.