Flexible, transparent, and fire-proof cellulose nanofibril films with outstanding flame retardancy

作者：Jierui Ye, Qingtian Xu, Yuebing Gao, Yipeng Liang, Qiang Wu, Guomin Wu, Siqun Wang, Pan Chen, Qian Li · 发表于：Industrial Crops and Products · 年份：2024 · DOI：10.1016/j.indcrop.2024.118210 · 被引用次数：22 · 研究领域：Advanced Cellulose Research Studies、Electromagnetic wave absorption materials、Lignin and Wood Chemistry

Naturally occurring cellulose nanofibril (CNF) is a major component of plant cell walls and possesses numerous advantages, including a high specific surface area, exceptional strength , abundant availability, renewability, and biodegradability. However, the inherent ignitability of CNF hinders its practical application in advanced functional materials . Herein, we report a novel ternary deep eutectic solvent , designed under mild mechanical grinding, capable of converting cheap bamboo cellulose into phosphorylated cellulose nanofibrils (PCNFs) uniform fibril diameters in the range of 3 − 10 nm. The pure PCNF-fabricated film exhibited excellent flame-retardant and self-extinguishing performances (with a high limiting oxygen index of 70.2%) without adding flame-retardants. Compared with unmodified CNF, the peak heat release rate and total heat release of the PCNF films decreased by 96.7% and 96.9%, respectively. Furthermore, defibrillation significantly improved the mechanical and optical properties of the PCNF films, suggesting considerable potential for applying PCNFs in flame-retardant packaging materials.