Mw. Jung et al., INTERACTION OF ORGANIC-COMPOUNDS WITH SILICA MATRIX PREPARED BY A SOL-GEL PROCESS FOR NLO APPLICATIONS, Molecular crystals and liquid crystals science and technology. Section A, Molecular crystals and liquid crystals, 247, 1994, pp. 111-120
In this work, MNA (2-methyl-4-nitroaniline) and substituted carbazoles
were incorporated into silica matrix to for composite thin films on t
he glass substrate by a sol-gel process for NLO applications. In the c
omposite thin films, the thermal stability was dependent on the type o
f functional groups incorporated into the organic compounds. DR 1(disp
erse red 1) and carbazole-2 (5-nitro-9-hydroxyethyl-cabazole) which ha
s a terminal -OH group showed enhanced thermal stability, whereas carb
azole-1 (5-nitro-9-ethyl-carbazole) and MNA, which don't have a reacti
ve functional group, showed rapid degradation upon thermal treatment.
This strongthly suggests that the thermal stability of incorporated or
ganic compounds can be enhanced by a reactive terminal group in organi
c compounds without severely damaging NLO properly.