Reaction Induced Conformational Change in Polyindole: Polyindole/PVA Film as Biomimetic Sensors of Temperature and Electrical Energetic Conditions

Abstract

The influence of surrounding temperature and electrical energetic condition on the conformational movements (cooperative actuation) of polyindole is verified using a polyindole‐coated polyvinyl alcohol (PIN/PVA) film. Chronopotentiometric studies reveals that the consumed electrical energy during the reaction varies linearly with the change in working temperature. The influence of temperature on the reversible conformational movements of the polymer chain is related to the charge consumed during the reaction. The logarithmic dependence of reversible redox charge obtained from coulovoltammogram with inverse of temperature further proved the temperature sensing characteristics and the influence of temperature on the cooperative actuation of the PIN/PVA film. The conformational relaxation increases as the temperature increases through hosting higher number of counter anions with the solvent molecule. The extension of the redox reaction or charge consumption was found to decrease as the scan rate increases. The double logarithmic relation between the consumed redox charge and the scan rate has proved that the electrical energetic condition can influence the conformational movement or the extension of the redox reaction in a reversible manner. The results suggest that the PIN/PVA film can act as a biomimetic macro molecular sensor of working temperature and electrical energetic condition as biological muscles do.

Structural electrochemistry of poly(3,4-ethylenedioxythiophene) and its applicability as simultaneous sensor of environmental surroundings: self-sensing electrical, thermal, and chemical working conditions

“…The electrical responses during reactions (consumed charge, consumed energy, potential evolution) are different for different working (chemical, thermal, electrical) conditions. 9 Signal, the order and the sensing responses, are included simultaneously within the only two connecting wires.…”

Bio-mimetic sensing characteristics of differently synthesized polyanilines towards the surrounding electrical and chemical energetic conditions

“…The inherent ability of conducting polymers, other than polypyrrole, to self-sense has not been extensively investigated. Ismail et al have recently published several studies on the responsive sensing properties of polyanilines [43], polyindole [9,44] and polyaniline composites [45]. Our team has synthesized six polyanilines with varying reaction times.…”