School of Chemistry and Chemical Engineering, South China University of Technology, Wushan Road 381, Guangzhou, 510640, PR China.
State Key Laboratory of Pulp and Paper Engineering, South China University of Technology, Wushan Road 381, Guangzhou, 510640, PR China.
Carbohydr Polym. 2021 May 1;259:117759. doi: 10.1016/j.carbpol.2021.117759. Epub 2021 Feb 10.
The simultaneous attainment of high strength and high toughness of transparent cellulose nanofibril (CNF) film can expedite its uses in advanced applications. In this work, a wood-inspired strategy is proposed to address the conflict between strength and toughness by using natural derived lignosulfonic acid (LA) as a reinforcing additive. Only 1 wt% LA addition can double the toughness (11.0±1.3 MJ/m) of pure CNF film. Consequently, the as-prepared CNF/LA-1 nanocomposite film not only exhibits superior mechanical properties (23.6±1.3 MJ/m toughness, 249±6 MPa strength, and 15.4±1.4 % strain), but also maintains an excellent optical transparency of 91.2 % (550 nm). Furthermore, the mechanism for simultaneously enhancing strength and toughness is essentially attributed to the improved hydrogen bonding between CNF-OH and LA-SOH and effective energy dissipation system. This work provides a green and effective approach to prepare strong yet tough and transparent biodegradable CNF film for high-end applications.
同时实现透明纤维素纳米纤维（CNF）薄膜的高强度和高韧性，可以加速其在先进应用中的使用。在这项工作中，提出了一种受木材启发的策略，通过使用天然衍生的木质素磺酸（LA）作为增强添加剂来解决强度和韧性之间的冲突。仅添加 1wt%的 LA 即可将纯 CNF 薄膜的韧性提高一倍（11.0±1.3 MJ/m）。因此，所制备的 CNF/LA-1 纳米复合材料薄膜不仅具有优异的力学性能（23.6±1.3 MJ/m 的韧性、249±6 MPa 的强度和 15.4±1.4%的应变），而且保持了 91.2%（550nm）的优异光学透明度。此外，同时提高强度和韧性的机制主要归因于 CNF-OH 和 LA-SOH 之间氢键的改善以及有效的能量耗散系统。这项工作为制备用于高端应用的强韧且透明的可生物降解 CNF 薄膜提供了一种绿色有效的方法。
