METHOD OF PRODUCING AEROGELS ON SiO BASIS Russian patent published in 2024 - IPC C08G77/04 C08G77/32 

FIELD: chemical technology of porous materials.

SUBSTANCE: invention relates to the development of a method of producing SiO₂-based aerogels, which are widely used in catalysis, sound, heat and electrical insulation; for storage and separation of gases; as damping and heat-resistant materials. The following is proposed: a method of producing aerogels from Si(OR')₄ and their mixtures with RSi(OR')₃ or Me₂Si(OR')₂, where R'=СН₃, С₂Н₅; R=СН₃, С₂Н₅, СН₂=СН, Н-C₈H₁₇, С₆Н₅, using a sol-gel process in the presence of HBF₄⋅OEt₂ as catalyst. The method involves producing a gel in organic solvents at temperatures from -25 to 100°C and atmospheric pressure. SiOR molar ratio'-group:H₂O:HBF₄⋅OEt₂ is 1:(0.125–0.625):(0.00625–0.300). Then the resulting gel undergoes “maturation” under the conditions of the sol-gel process. Then drying the gel is carried out in supercritical carbon dioxide.

EFFECT: proposed method of producing SiO₂-based aerogels from a wide range of alkoxysilanes ensures rapid formation of a gel under mild conditions and does not require its processing to convert it into an airgel.

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