The kinetic parameters and the structural change of thermal degradation of
phenolic resin/silica hybrid ceramers with different mixing ratios were inv
estigated. The activation energies of thermal degradation were calculated b
y the methods of Kissinger, Friedman and Ozawa from a conventional dynamic
thermogravimetric measurement in nitrogen atmosphere at several different h
eating rates. Both pure phenolic resin and hybrid ceramers show two stages
of degradation; however, the activation energies of thermal degradation of
the ceramers in the first stage are all lower than that of phenolic resin.
FT-IR spectra show that the formation of silica network structure was restr
icted by intermolecular hydrogen bonding at lower temperature. However, the
restriction disappears when the phenolic resin starts to degrade at high t
emperature. TGA/MS investigations show that the presence of sor-gel silica
causes some changes in the degradation mechanism of the hybrid ceramers. (C
) 2000 Elsevier Science Ltd. All rights reserved.