The high cost and weak mechanical properties of silica-based aerogel seriously affect its wide application in the field of building insulation. In this paper, low-cost SiO aerogel (WSA) was prepared based on water glass/water system, and the modulation of aerogel network structure was achieved under the dual effect of sodium methylsilicate (SMS) and pH. WSA exhibits extremely low density (∼88.5 kg/m) and thermal conductivity (0.02114 W/(m·K)) as well as high hydrophobicity (150°). The cost of WSA is 53 % lower compared to atmospheric pressure drying and 21.5 % lower than commercial aerogel. On this basis, rock wool fiber felt (RWF) and ultrafine glass fiber wool felt (UGFW) were modified with WSA. The effect of fiber arrangement on the force-thermal coupling property of WSA@RWF was investigated. Meanwhile, the addition of WSA reduced the volumetric water absorption of RWF by 85.1 % and 91.4 %. Since the sandwich structure, the thermal conductivity of WSA@UGFW can be as low as 0.01168 W/(m·W), which is 44.7 % and 44.4 % lower than that of UGFW and WSA. It features a low density of 45.7 kg/m and a high hydrophobicity angle of 155.87°. In addition, the compressive strength of WSA@UGFW is increased by 16.5 times. Therefore, the aerogel materials prepared in this paper have great application potential as fire-proof building insulation materials.

中文翻译：

---

建筑保温用低成本气凝胶复合材料的结构性能和阻隔性能


硅基气凝胶成本高、力学性能弱，严重影响其在建筑保温领域的广泛应用。本文基于水玻璃/水体系制备了低成本SiO气凝胶(WSA)，并在甲基硅酸钠(SMS)和pH的双重作用下实现了气凝胶网络结构的调控。 WSA 具有极低的密度 (∼88.5 kg/m) 和导热率 (0.02114 W/(m·K)) 以及高疏水性 (150°)。 WSA 的成本比常压干燥低 53%，比商业气凝胶低 21.5%。在此基础上，用WSA对岩棉纤维毡（RWF）和超细玻璃纤维棉毡（UGFW）进行改性。研究了纤维排列对WSA@RWF力热耦合性能的影响。同时，WSA的添加使RWF的体积吸水率分别降低了85.1%和91.4%。由于采用三明治结构，WSA@UGFW的导热系数可低至0.01168 W/(m·W)，比UGFW和WSA分别低44.7%和44.4%。它具有 45.7 kg/m3 的低密度和 155.87° 的高疏水角。此外，WSA@UGFW的抗压强度提高了16.5倍。因此，本文制备的气凝胶材料作为防火建筑保温材料具有巨大的应用潜力。