| abstract |
The invention relates to a process for producing xerogel composites, which comprises:n (a) provision of a composition comprising an organic gel precursor (A) comprising a monomer component (A1) composed of at least one polyfunctional isocyanate and a monomer component (A2) composed of at least one compound selected from among polyfunctional amines and polyfunctional hydroxy compounds; (b) reaction of the gel precursor (A) in the presence of an open-celled macroporous foam (B) and a solvent (C) to form a xerogel composite; (c) drying of the xerogel composite by conversion of the solvent (C) into the gaseous state at a temperature and a pressure below the critical temperature and the critical pressure of the solvent (C). nn The invention further relates to the xerogel composites which can be obtained in this way and their use as insulating material, for thermal insulation, vacuum insulation panels, in refrigeration units or in buildings. |