Silica aerogels are considered as the distinguished materials of the future due to their extremely low thermal conductivity, low density, and high surface area. They are widely used in construction engineering, aeronautical domains, environmental protection, heat storage, etc. However, their fragile mechanical properties are the bottleneck restricting the engineering application of silica aerogels. This review briefly introduces the synthesis of silica aerogels, including the processes of sol–gel chemistry, aging, and drying. The effects of different silicon sources on the mechanical properties of silica aerogels are summarized. Moreover, the reaction mechanism of the three stages is also described. Then, five types of polymers that are commonly used to enhance the mechanical properties of silica aerogels are listed, and the current research progress is introduced. Finally, the outlook and prospects of the silica aerogels are proposed, and this paper further summarizes the methods of different polymers to enhance silica aerogels.

In order to recycle the waste, the wasted bagasse was applied as fireretardant filler to prepare the waterborne intumescent fireproof coating.The effects of bagasse on the properties of the fireproof coating were investigated by fire protection test, thermogravimetric analysis, smoke suppression test, scanning electron microscope, energy dispersive spectrometer, Xray diffraction, Fourier transform infrared spectroscopy, water resistance test and mechanical properties test. The result demonstrated the coating with 1.5% bagasse performed best in the fire protection, thermal stability, and smoke suppression test. Moreover, the char layer of the sample after the fire protection was dense and continuous. However, the fireproof coating contained 2% bagasse had excellent performance in water resistance test and mechanical properties test due to the properties of fiber. Furthermore, the components and chemical structure of char layers were characterized to study the flame retardant mechanism of bagasse in the fireproof coating.