
1: CARBAZOLE POLYMERS 27
However, significant differences occur in compos-
ites with a glass transition temperature above the tem-
perature of measurement. In this case, the composites
with the highest chromophore content show the best
steady-state performance. However, their response
time is much slower than that for those containing
lower chromophore content. Reversible photorefrac-
tive grating and irreversible local photoinduced aggre-
gation grating could be established in a low glass tran-
sition temperature polymer composite of PVK, TNF,
ECZ, and N-(4-nitrophenyl)-1-prolinol [189].
1.4.4 Photovoltaic Devices
The photovoltaic process is just the rev ...