从分析纳米隔热材料的传热机理入手，指出微米／亚微米孔隙结构特征是决定其是否具有“超级隔热”性能的关键因素。以常温常压下热导率0．02W／m·K为目标，利用理论计算方法获得了纳米超级隔热材料大孔孔隙尺寸及其所占体积分数的最大容限，并采用SiO2纳米隔热材料的测试结果进行了验证。以满足1000℃以上使用要求作为目标，制备了1200℃下结构稳定性良好的SiO2－Al2O3复合纳米超级隔热材料，采用自行研制的超低热导率测试样机对不同温度和压力条件下的热导率进行测试，并与石英灯加热法测评试样热导率的实验结果进行了对比。最后提出了本领域存在的其它难题，展望了纳米超级隔热材料的未来发展潜力。
Nano-porous superinsulation materials have uhro-low thermal conductivities, which depends on the micro/ sub-micrometer porous structure. The macropore volume limitation is calculated and validated for silica aerogel of 0.02 W/ m . K at 20 ℃ under atmosphere. SiO2-Al2O3 nanoporous insulation materials with high thermal stability at 1 200 ℃ have been synthesized. The thermal conductivities have been tested and compared with the quartz lamp heater experiment results. The potential development of nano-porous superinsulation materials in future is also reviewed.
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