Hou Minjie, Wang Qi, Wang Shunyu, Yang Zeze, Deng Xuefeng, Zhao Hailong
School of Materials Engineering, Taiyuan Institute of Technology, Taiyuan 030008, China.
Gels. 2024 Jul 25;10(8):490. doi: 10.3390/gels10080490.
Cellulose nanofibers (NF) were extracted from kapok fibers using TEMPO oxidation, followed by a combination of mechanical grinding and ultrasonic processing. The TEMPO-mediated oxidation significantly impacted the mechanical disintegration behavior of the kapok fibers, resulting in a high NF yield of 98%. This strategy not only improved the fibrillation efficiency but also reduced overall energy consumption during NF preparation. An ultralight and highly porous NF-based aerogel was successfully prepared using a simple ice-templating technique. It had a low density in the range of 3.5-11.2 mg cm, high compressional strength (160 kPa), and excellent thermal insulation performance (0.024 W m K). After silane modification, the aerogel displayed an ultralow density of 7.9 mg cm, good hydrophobicity with a water contact angle of 128°, and excellent mechanical compressibility with a high recovery of 92% at 50% strain. Benefiting from the silene support structure, it showed a high oil absorptive capacity (up to 71.4 g/g for vacuum pump oil) and a remarkable oil recovery efficiency of 93% after being reused for 10 cycles. These results demonstrate that our strategy endows nanocellulose-based aerogels with rapid shape recovery and high liquid absorption capabilities.
采用TEMPO氧化法从木棉纤维中提取纤维素纳米纤维（NF），然后结合机械研磨和超声处理。TEMPO介导的氧化显著影响了木棉纤维的机械崩解行为，NF产率高达98%。该策略不仅提高了原纤化效率，还降低了NF制备过程中的总能耗。使用简单的冰模板技术成功制备了一种超轻且高度多孔的NF基气凝胶。它的密度很低，在3.5-11.2 mg/cm范围内，具有较高的抗压强度（160 kPa）和优异的隔热性能（0.024 W/(m·K)）。经过硅烷改性后，气凝胶的密度超低，为7.9 mg/cm，具有良好的疏水性，水接触角为128°，并且具有优异的机械压缩性，在50%应变下的高回复率为92%。受益于硅烷支撑结构，它表现出高吸油能力（真空泵油高达71.4 g/g），并且在重复使用10次后具有93%的显著油回收效率。这些结果表明，我们的策略赋予了纳米纤维素基气凝胶快速形状恢复和高液体吸收能力。
