| abstract |
The invention relates to the technical field of aerogels, in particular to a preparation method of large-sized transparent silica aerogel blocks. It includes the following steps: stirring and mixing 3-aminopropyl triethoxysilane, methyl orthosilicate and absolute ethanol, then adding deionized water to continue mixing; adding a hydrolysis catalyst to the mixed solution, making it hydrolyzed, and then Add the polycondensation catalyst, stir and let stand, then add dry ice-acetone to make it gel, and finally react with organic monomers with isocyano groups to obtain polyurea-crosslinked silica Wet gel; after the wet gel is formed, add ethanol, reinforcing material, fiber woven sheet and a mixture of silicon source precursor, and after aging, supercritical carbon dioxide drying is performed to obtain a silica aerogel block; this step is prepared in the following steps: The silica aerogel has good bulk, light transmittance, heat insulation and mechanical properties. |