Abstract: Silica aerogel has a unique nano-network framework structure, which endows it with extremely high porosity and extremely low density. The complex micro-nano structure of silica aerogel can effectively block thermal convection, making it with extremely low thermal conductivity. Si—O—Si with excellent heat resistance constitutes the main structure of silica aerogel. Silica aerogel has a wide range of applications in building thermal insulation, aerospace thermal protection, sound absorption and noise reduction, weapon equipment manufacturing and other fields. Silica aerogel is one of the main research and development directions of thermal protection materials at home and abroad. However, silica aerogel has the disadvantages of low strength and poor continuity of nano-network skeleton structure, poor physical and chemical combination of nano-pore structure, and high brittleness of related products, which makes it difficult to combine thermal protection and load-bearing. In this paper, from the three perspectives of skeleton reinforcement, polymer reinforcement and second phase reinforcement, the research status and existing problems of silica aerogel reinforcement technology are discussed. This paper summarizes the research status of silica aerogel reinforcement technology at home and abroad, and provides ideas for the future development of silica aerogel framework reinforcement technology.

Key words: silica aerogel, fiber reinforcement, polymer reinforcement, structural reinforcement