Silica aerogel reinforced with cellulosic sponge and process for its preparation

The invention relates to a process for manufacturing a hybrid aerogel, which comprises preparing first a three-dimensional (3D) cellulosic sponge starting from a suspension comprising short cellulose fibers of less than 2 mm in average length, squeezing said cellulosic sponge to eliminate part of its water content, soaking the squeezed cellulosic sponge with a silica sol-gel precursor solution and carrying out a sol-gel method. The invention also relates to the hybrid aerogel obtainable by said process and to its use in manufacturing of thermal and/or acoustic insulation elements.