Poly(''p''-phenylene) (PPP) is made of repeating ''p''-

phenylene In organic chemistry, the phenylene group () is based on a di-substituted benzene ring ( arylene). For example, poly(''p''-phenylene) is a polymer built up from ''para''-phenylene repeating units.p. C-9, Section 11.6, Handbook of Chemistry and ...

units, which act as the precursor to a

conducting polymer Conductive polymers or, more precisely, intrinsically conducting polymers (ICPs) are organic polymers that conduct electricity. Such compounds may have metallic conductivity or can be semiconductors. The main advantage of conductive polymers i ...

of the rigid-rod polymer family. The synthesis of PPP has proven challenging, but has been accomplished through excess polycondensation with the Suzuki coupling method. Early efforts typically produced black, insoluble powders that were difficult to characterize. For example, a 1962 paper reports "The solid glowed red-hot in a Bunsen flame, with no evidence of flame formation, and disappeared only slowly." (J. Polym. Sci. (1960), 47, 45) Initially, the chemical and thermal stability of the material drove interest in its synthesis. It was used in rocket nozzles and some fabrics requiring high thermal stability.

Oxidation Redox ( , , reduction–oxidation or oxidation–reduction) is a type of chemical reaction in which the oxidation states of the reactants change. Oxidation is the loss of electrons or an increase in the oxidation state, while reduction is ...

or the use of

dopant A dopant (also called a doping agent) is a small amount of a substance added to a material to alter its physical properties, such as electrical or optics, optical properties. The amount of dopant is typically very low compared to the material b ...

s is used to convert the non-conductive form to a

semiconductor A semiconductor is a material with electrical conductivity between that of a conductor and an insulator. Its conductivity can be modified by adding impurities (" doping") to its crystal structure. When two regions with different doping level ...

References

External links

Rigid-rod polymer host
Polymer chemistry Phenylene compounds {{Polymer-stub