Phenolic and carbon aerogels have important applications for thermal insulation and ablative resistance materials in aerospace field. However, their antioxidant ability in long-term high-temperature aerobic environments faces serious challenges. To solve this problem, Zr/Si preceramic polymer hybridized phenolic resin (PR-ZS) aerogels were prepared via a facile sol–gel method. Compared with pure phenolic aerogel, the hybrid aerogels possess similar porous microstructure but larger specific surface area, better thermo-oxidative stability, and higher compressive strength. After carbonization at 1700 °C, the hybrid aerogels can be transformed to carbide ceramic aerogels with ultrafine nanocrystalline ZrC and SiC particles embedded in the carbon matrix. Ceramic aerogels exhibit good thermal insulative and anti-ablative properties in a butane torch simulated high-temperature and aerobic environment. The linear ablation rate is as low as 0.017 mm min⁻¹, and the backside temperature is below 330 °C at a 20 mm in-depth position after 300 s of burning test, when the front temperature is approximately 960 °C. This work provides a facile approach to fabricate hybrid phenolic aerogels and derived ZrC/SiC/C ceramic aerogels, which target on applications for extreme environments in aerospace field.

中文翻译：

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预陶瓷聚合物杂化酚醛气凝胶和衍生的具有超细纳米晶的 ZrC/SiC/C 陶瓷气凝胶


酚醛和碳气凝胶在航空航天领域的隔热和抗烧蚀材料中具有重要的应用。然而，它们在长期高温有氧环境中的抗氧化能力面临严峻的挑战。为解决这一问题，采用简单的溶胶-凝胶法制备了Zr/Si预陶瓷聚合物杂化酚醛树脂（PR-ZS）气凝胶。与纯酚醛气凝胶相比，杂化气凝胶具有相似的多孔微观结构，但比表面积更大，热氧化稳定性更好，抗压强度更高。在 1700 °C 碳化后，杂化气凝胶可以转化为碳基体中嵌入超细纳米晶 ZrC 和 SiC 颗粒的碳化物陶瓷气凝胶。陶瓷气凝胶在丁烷火炬模拟高温和好氧环境中表现出良好的隔热和抗烧蚀性能。线性烧蚀速率低至 0.017 mm ^min-1，经过 300 s 的燃烧测试后，背面温度在 20 mm 深度位置低于 330 °C，此时前部温度约为 960 °C。 这项工作为制备杂化酚醛气凝胶和衍生的 ZrC/SiC/C 陶瓷气凝胶提供了一种简便的方法，其目标适用于航空航天领域的极端环境应用。