Han Ding, Sun Xiankai, Zhang Shichao, Wu Linghao, Ai Bing, Sun Haoran, Chen Yufeng
China Building Materials Academy Co., Ltd No. 1 Guan Zhuang Dong Li, Chaoyang District Beijing 100024 P. R. China
RSC Adv. 2024 Mar 1;14(11):7350-7358. doi: 10.1039/d4ra00109e. eCollection 2024 Feb 29.
High-performance thermal insulation materials with broad application prospects have attracted great attention. The introduction of new microstructures into thermal protection materials can significantly improve the thermal insulation performance. The tubular microstructure has obvious advantages such as thermal insulation, lightweight, mechanical, and other properties. Therefore, the microtubular structure has become an important reference microstructure for the development of high-performance thermal insulation materials. In this paper, the carbon/ZrO aerogel composite microtube superfoams with excellent thermal protection properties were prepared by a vacuum filtration and high-temperature carbonization method. The ZrO aerogel precursor solution can be quickly and uniformly adsorbed on the inner and outer walls of cellulose microtubules. These adsorbed ZrO aerogel precursor solution films can be converted into ZrO alcohol gel shells under the acceleration and promotion effect of citric acid at 65 °C. The micromorphology of the ZrO aerogel shell on the inner and outer walls of the composite microtubes can be efficiently controlled by the concentration of the ZrO aerogel precursor solution and the carbonization temperature. The carbon/ZrO aerogel composite microtube superfoam exhibits a lower thermal conductivity, lower density, good mechanical properties, and high ablation resistance. The thermal conductivity of the carbon/ZrO aerogel composite microtube superfoam is as low as 0.040 ± 0.001 W m K. The residual rate of the carbon/ZrO aerogel composite microtube superfoam is still as high as 84.33% after butane flame ablation for up to 3600 seconds.
具有广阔应用前景的高性能隔热材料备受关注。在热防护材料中引入新的微观结构可显著提高隔热性能。管状微观结构在隔热、轻质、机械等性能方面具有明显优势。因此，微管结构已成为高性能隔热材料发展的重要参考微观结构。本文采用真空过滤和高温碳化法制备了具有优异热防护性能的碳/ZrO气凝胶复合微管超泡沫材料。ZrO气凝胶前驱体溶液能快速均匀地吸附在纤维素微管的内壁和外壁上。在65℃柠檬酸的加速促进作用下，这些吸附的ZrO气凝胶前驱体溶液膜可转化为ZrO醇凝胶壳。通过ZrO气凝胶前驱体溶液的浓度和碳化温度可有效控制复合微管内壁和外壁上ZrO气凝胶壳的微观形貌。碳/ZrO气凝胶复合微管超泡沫材料具有较低的热导率、较低的密度、良好的机械性能和高耐烧蚀性。碳/ZrO气凝胶复合微管超泡沫材料的热导率低至0.040±0.001W m K。在丁烷火焰烧蚀长达3600秒后，碳/ZrO气凝胶复合微管超泡沫材料的残留率仍高达84.33%。
