▎ 摘　　要

NOVELTY - Preparing high-temperature resistant insulating aerogel felt comprises e.g. (i) dispersing silicon carbide whiskers and cellulose in graphene aqueous suspension to obtain suspension A, (ii) adding hollow glass microspheres into suspension A under stirring to obtain suspension B, (iii) mixing orthosilicate, ethanol and water, adding ammonium fluoride solution and aqueous ammonia and stirring to obtain silica sol C, (iv) adding suspension B to silica sol C under stirring, soaking fiber mat, immersing fiber mat under vibration conditions, impregnating, removing fiber mat and allowing to stand to obtain fiber mat-gel composite, (v) removing fiber mat-gel composite and performing aging treatment at room temperature or under heating, (vi) placing fiber felt-gel composite in absolute ethanol for solvent replacement and removing excess water from fiber mat-gel composite, and (vii) drying fiber felt-gel composite to obtain final product. USE - The method is useful for preparing high-temperature resistant insulating aerogel felt. ADVANTAGE - The aerogel felt: has strong high-temperature resistance and heat insulation effect; and improves mechanical strength. DETAILED DESCRIPTION - Preparing high-temperature resistant insulating aerogel felt comprises (i) dispersing silicon carbide whiskers and cellulose in graphene aqueous suspension to obtain suspension A, (ii) adding hollow glass microspheres into suspension A under stirring to obtain suspension B, (iii) mixing orthosilicate, ethanol and water evenly, adding ammonium fluoride solution and aqueous ammonia and stirring evenly to obtain silica sol C, (iv) adding suspension B to silica sol C under stirring, soaking fiber mat, immersing fiber mat under vibration conditions, impregnating, removing fiber mat and allowing to stand to obtain fiber mat-gel composite, (v) removing fiber mat-gel composite obtained in step (iv) and performing aging treatment at room temperature or under heating, (vi) placing fiber felt-gel composite obtained in step (v) in absolute ethanol for solvent replacement and removing excess water from fiber mat-gel composite, and (vii) drying fiber felt-gel composite obtained in step (vi) to obtain final product, where solid content of graphene aqueous suspension is 1-5g/l, in step (iii), mass ratio between silicon carbide whisker, cellulose, graphene, hollow glass beads and orthosilicate is 5-20:1-5:1-5:10-20:300-350, molar ratio between orthosilicate, ethanol and water is 1:4-12:2-4, in step (iii), molar ratio between ammonium fluoride solution and orthosilicate is 0.002-0.01:1, and molar ratio between aqueous ammonia and orthosilicate is 0.005-0.015:1.