Gas and vapour detection using polypyrrole

The vapours of organic solvents like toluene, butanon, and ethanol do effect the electrical conductivity of electrochemically synthesised polypyrrole. This property allows the use of polypyrrole in sensors for vapour detection. The conductivity is also a function of temperature and the history of the sensor. When exposed to water vapour, the conductivity decreases. Moreover, the polymer degrades during exposure to humid air.