Resorcinol/formaldehyde aerogel fine powders with nanopore structure prepared by supercritical CO₂ drying techniques

The preparation of resorcinol/formaldehyde (R/F) aerogel powders with nanopore structure by means of the supercritical CO₂ drying technique has been studied. Spherical morphology of R/F aerogel powders was confirmed by scanning electron microscopy. The sizes of these fine powders ranged from 4 micrometer to a few hundred micrometers. The particle sizes were controlled by the emulsification conditions. The structure of R/F aerogel powder was revealed by FT-IR and BET analysis. The surface area and pore size of R/F aerogel powders with a fibrous-like network are in the range of 400 m²/g to 800 m²/g and less than 100 nm, respectively.