Resorcinol-formaldehyde aerogels prepared by supercritical acetone drying

Preparation of resorcinol formaldehyde (RF) aerogels by the aqueous polycondensation of resorcinol with formaldehyde and supercritical acetone drying is reported. A comparison of the basic physical properties between an RF aerogel from supercritical acetone drying and an RF aerogel from supercritical CO2 drying was carried out. It is found that the shrinkage and density of the RF aerogel from supercritical acetone drying are larger than those of the RF aerogel with supercritical CO2 drying. The experimental use of an initial nitrogen pressure shows that the gel texture can be preserved using supercritical acetone drying. Examination of the materials obtained by SEM, TEM and FT-infrared spectroscopy shows similar data to those of RF aerogel prepared by supercritical CO2 drying. (C) 2000 Published by Elsevier Science B.V. All rights reserved.