New carbon nanotube insulation can resist temperatures exceeding 4,700°F

Chinese researchers at Tsinghua University have developed a novel carbon nanotube-based insulation film capable of withstanding temperatures up to 4,712°F (2,600°C), significantly surpassing the limits of conventional insulators that typically fail above 2,732°F (1,500°C). This ultralight, porous, multilayered material is made by growing vertical carbon nanotube arrays and drawing them into thin sheets, which are then stacked or wound into layers. The structure effectively blocks all three modes of heat transfer—solid conduction, gas conduction, and radiative heat transfer—by exploiting the nanotubes’ nanoscale dimensions, pore size, and unique electronic properties that absorb and scatter infrared radiation. The new insulation exhibits an exceptionally low thermal conductivity of 0.004 W/mK at room temperature and 0.03 W/mK at 2,600°C, outperforming common high-temperature insulators like graphite felt, which has a thermal conductivity of 1.6 W/m