FIELD: preparation of modified aerogels used as heat-insulating material. SUBSTANCE: method comprises reacting SiO2 gel with silylating agent of formula: 
wherein R1 is linear or branched C1-C6 alkyl residue, cyclohexyl residue or phenyl residue; R2, R3 and R4, the same or different, are hydrogen, atoms, linear or branched C1-C6 alkyl residues, cyclohexyl residues or phenyl residues, and n is 1,2 or 3, and drying the product. The resulting aerogels have density of lower than 0.6 g/cubic cm, and porosity of higher than 60% and hence have low thermal conduction. This enables one to use then as heat-insulating material. EFFECT: more efficient preparation method. 12 cl, 3 ex
