Chemical sensors based on electroactive polymers: First example of the use of a polyphenylenethienylene derivative

The behaviour of an alternating co-polymer, poly(2,5-dioctyloxy-1,4-phenylene-alt-2,5-thienylene), has been first investigated at the air-water interface. The floating has been analysed by monitoring Langmuir curves and Brewster angle microscopy. The floating films were deposited by the Langmuir- Schafer (horizontal lifting) technique onto various substrates. It is evident from experimental data that a strong co-planarity and interchain association originates above all in the floating film on the water surface and in the transferred multilayers. Such films were used as the active layers in resistive chemical gas sensor device, thus revealing excellent sensitivity towards NO2, reversibility and time stability of the response.