Author:
McNeill R,Siudak R,Wardlaw JH,Weiss DE
Abstract
The pyrolysis of tetraiodopyrrole in an
inert atmosphere at temperatures from 120-700� yields black, infusible,
amorphous polymers insoluble in solvents. Depending on the pyrolysis
temperature, iodine may be present in the polymers as iodine of substitution
and as chemisorbed molecular iodine, which is very tenaciously held. As a first
approximation, the structure may be regarded as a three-dimensional network of
pyrrole rings cross-linked in a nonplanar fashion by direct carbon to carbon
linkages. The secondary nitrogen atoms form a hydroquine type system which may
be oxidized by iodine or molecular oxygen under alkaline conditions. The extent
of oxidation depends on the hydroxyl ion concentration. The nonplanarity of the
oxidized quinonoid system renders it unstable but stability is enhanced, as in
the triphenylmethane dyestuffs, by the formation of a carbinol.
Despite their nonplanarity polypyrroles
are relatively good conductors of electricity. The resistivity ranges from
1-200 ohm cm depending on the temperature of pyrolysis.
Cited by
162 articles.
订阅此论文施引文献
订阅此论文施引文献,注册后可以免费订阅5篇论文的施引文献,订阅后可以查看论文全部施引文献