Nonconjugated conductive polymers

Conjugation is not a prerequisite for a polymer to be conductive. A polymer must have at least one double bond in the repeat to become conductive. Interaction with a dopant (e.g., electron acceptor) causes transfer of an electron from the double bond to the dopant creating a hole at the double bond site. Electrical conduction occurs via intersite hopping of holes. Various spectroscopic methods (FTIR, optical absorption, solid-state C-13 NMR, etc.) along with electrical measurements have been used to elucidate the mechanism of conduction in specific nonconjugated conductive polymers. Examples of these polymers include 1,4-polyisoprene which has one double bond and three single bonds in the repeat. The conductivity of polyisoprene increases 100 billion times upon doping with iodine to a maximum value of 10 S/m. Polyisoprene (natural rubber) is used nonconjugated conductive polymers have a wide range of applications in antistatics, various sensors and optoelectronics.