Abstract: The present invention relates to a solid thermally insulating material, essentially free of phyllosilicates, comprising (a) from 70 to 98% by volume of hydrophobic silica aerogel particles having an intrinsic density between 110 and 210 kg/m, (b) from 0.3 to 12% by volume of an organic binder formed by at least one organic polymer (b1) and at least one surfactant (b2), or by an amphiphilic organic polymer (b3), these volume fractions being determined by image analysis on thin sections of the solid material and being given relative to the total volume of the material, the aerogel particles having a particle size distribution that has at least two maxima, with a first maximum corresponding to an equivalent diameter (d) of less than 200 ?m, preferably between 25 ?m and 150 ?m, and a second maximum corresponding to an equivalent diameter (D) between 400 ?m and 10 mm, preferably between 500 ?m and 5 mm. It also relates to a thermally insulating product containing at least one layer of this material.