Resorcinol-formaldehyde (RF) gels were synthesized by sol-gel polycondensat
ion of resorcinol with formaldehyde to prepare mesoporous carbon precursors
. RF cryogels were prepared by freeze drying of RF gels, where t-butanol an
d water were used as solvents. The freezing temperature, the number of repe
titive rinse times with t-butanol, and the sample size were changed in the
preparation of RF cryogels. Porous properties of the RF cryogels were estim
ated by N-2 adsorption. The influence of freeze-drying conditions was eluci
dated on the mesoporosity of RF cryogels. Freeze drying of RF gels with t-b
utanol developed more mesopores than freeze drying with water. The freezing
temperature of the gels did not greatly influence the porous properties of
the cryogels. If the gels were repeatedly rinsed with t-butanol and freeze
-dried in smaller sizes, the cryogels were favorable for use as mesoporous
carbon precursors. (C) 2000 Elsevier Science Ltd. All rights reserved.