Conductive polymers - the story.
Conductive polymers are a sub-group of a larger, older group of organic and inorganic electrical conductors.
In fact, as early as 1862 H. Letheby of the College of London Hospital, by anodic oxidation of aniline in.
sulphuric acid, obtained a partly conductive material which was probably polyaniline. In the early 1970s, it.
was found that the inorganic explosive polymer, poly(sulphur nitride) (SN)x, was superconductive at.
extremely low temperatures (Tc=0.26 K). Many conductive organic compounds were also known, such as.
those discovered by K. Bechgaard (Copenhagen) together with D. Jerome (Paris) and famous for being.
superconductive at rather "high- temperatures (Tc around 10 K). They are salts of inorganic acceptors and.
organic donors consisting of large, cyclically conjugated electron systems that form coin-pile stacks in the.
solid state.
However, polyacetylene was the conductive polymer that actually launched this new field of research (Refs 1-.
4). For details of its history see the excellent review articles by Feast, et al., 5 and by M.G.Kanatzidis, 6.
summarised below (see also Refs 7" .
Natta and co-workers prepared polyacetylene in 1958 by polymerising acetylene in hexane using.
Et3Al/Ti(OPr)4 (Et= ethyl, Pr=propyl) as a catalyst. Though the resulting material was highly crystalline and.
of regular structure, it was a black, air-sensitive, infusible and insoluble powder. Ziegler-Natta polymerisation.
was developed for polymerising alkenes such as ethylene by inserting an unsaturated molecule into the.
carbon-titanium bond of the growing macromolecule. It depends greatly on the activity of the choice of.
catalyst system. In the early 1970s Shirakawa and co-workers adapted the method to make well-defined films.
of polyacetylene.
A major discovery by Shirakawa was that this polymerisation could be effected at the surface of a.
concentrated solution of the catalyst system in an inert solvent.
