Lu Yingying, Qin Zhiyong, Gao Wei, Deng Shuduan, Li Cheng, Liu Zhigao, Mo Liuting
School of Resources Environment and Materials, Guangxi University, Nanning 530004, China; State Key Laboratory of Featured Metal Materials and Life-cycle Safety for Composite, Guangxi University, Nanning 530004, China.
Yunnan Key Laboratory of Wood Adhesives and Glue Products, Southwest Forestry University, Kunming 650224, China.
Int J Biol Macromol. 2025 Jul;318(Pt 4):145190. doi: 10.1016/j.ijbiomac.2025.145190. Epub 2025 Jun 16.
Nanocellulose aerogels with low thermal conductivity, lightweight, and abundant pore structures are widely used in thermal insulation materials. However, the growing need for environmental protection places new, stringent demands on the sustainability of aerogels. Herein, an all-natural aerogel with an oriented porous structure, excellent flame retardancy, and low thermal conductivity was prepared, which included bamboo cellulose nanofiber (CNF) framework, sodium alginate (SA) cross-linking, and sodium-based montmorillonite (Na-MMT) for thermal insulation and flame retardancy. The resulting aerogel with a channel structure similar to that of natural wood contributes to low thermal conductivity (21.1 mW/(m·K)) and excellent mechanical properties. The deposition of Na-MMT and CaCl endowed the aerogel with excellent flame retardancy (an ultimate oxygen index of 90 %, a peak heat release rate as low as 19.34 kW/m, and a total smoke production rate as low as 0.122 m), enhanced compressive strength (208.5 kPa) and elastic modulus (261.1 kPa). Finally, its all-natural raw materials make aerogel extremely biodegradable and sustainable, thus reducing the damage of waste materials to the natural environment. This natural wood-like aerogel has outstanding flame retardancy, low thermal conductivity, and excellent mechanical properties, and can be used as an important green building material.
具有低导热性、轻质且孔隙结构丰富的纳米纤维素气凝胶被广泛应用于保温材料中。然而，对环境保护日益增长的需求对气凝胶的可持续性提出了新的严格要求。在此，制备了一种具有定向多孔结构、优异阻燃性和低导热性的全天然气凝胶，其包括竹纤维素纳米纤维（CNF）骨架、海藻酸钠（SA）交联以及用于保温和阻燃的钠基蒙脱石（Na-MMT）。所得具有与天然木材类似通道结构的气凝胶有助于实现低导热性（21.1毫瓦/（米·开尔文））和优异的机械性能。Na-MMT和CaCl的沉积赋予气凝胶优异的阻燃性（极限氧指数为90%，峰值热释放速率低至19.34千瓦/米，总产烟速率低至0.122米）、增强的抗压强度（208.5千帕）和弹性模量（261.1千帕）。最后，其全天然原料使气凝胶具有极高的生物降解性和可持续性，从而减少了废料对自然环境的破坏。这种天然木材状气凝胶具有出色的阻燃性、低导热性和优异的机械性能，可作为一种重要的绿色建筑材料。
