14 HIGH PERFORMANCE POLYMERS
1.4.1.4 Copolymers
A photoconductive sol-gel material based on an
organic/inorganic interpenetrating network has been
described. PVK acts as the charge transporting matrix
and TNF acts as the sensitizer [80].
Hole Transport Electron Acceptor Systems.
NVK as the hole transport monomer can be copoly-
merized with electron t ransport monomers. Examples
of such monomers are 2-phenyl-5-4-[(4-vinylphe-
nyl)methoxy]phenyl-1,3,4-oxadiazole and 2-(4-tert-
butylphenyl)-5-4-[(4-vinylphenyl)methoxy]phenyl-1,
3,4-oxadiazole [6].
The polymerization proceeds as free radical copoly-
merization and statistical copolymers are obtained.
Thus, the composition of the copolymers can be var-
ied and the conductive properties can be tailored. The
copolymers ...