Aerogels have many unique properties such as low density and low thermal conductivity, and, in particular, transparent silica aerogels are attractive for thermal insulating windows. Practical applications of silica aerogels, however, have been limited because of their low mechanical strength, and it is still challenging to synthesize transparent and mechanically strong aerogels. Here, we report colorless transparent melamine–formaldehyde (MF) aerogels prepared via a nonaqueous synthetic strategy. The obtained transparent MF aerogel with a density of 0.18 g cm^–3 shows significantly higher mechanical strength and a lower thermal conductivity of ca. 13 mW m^–1 K^–1 compared to conventional silica aerogels with similar density.

中文翻译：

---

用于隔热的无色透明三聚氰胺-甲醛气凝胶

气凝胶具有许多独特的特性，例如低密度和低导热性，尤其是透明的二氧化硅气凝胶对于隔热窗很有吸引力。然而，由于二氧化硅气凝胶的机械强度低，其实际应用受到限制，并且合成透明且机械强度高的气凝胶仍然具有挑战性。在这里，我们报告通过无水合成策略制备的无色透明三聚氰胺-甲醛（MF）气凝胶。所获得的透明MF气凝胶的密度为0.18 g cm ^-3，显示出明显更高的机械强度和更低的导热系数。与具有类似密度的传统二氧化硅气凝胶相比，其功率为13 mW m ^–1 K ^–1。