Modulating the electronic properties of pendant groups through the redox switching reaction of a conjugated polymer

In this work we use the switching reaction of conductive polymers as a macroscopic reversible command of the microscopic electronic properties of phenyl nuclei grafted on the polymer backbone. Two approaches, that potentially could enhance the modulation of these electronic properties, are investigated by means of IR spectroscopy: (i) the first consists in diluting the substituents along the polymer backbone by copolymerization of pyrrole and N-phenylpyrrole; (ii) in the second, 1,4-di(N-pyrrolyl)benzene (DPB) homopolymers are used and make it possible to graft two conductive chains on the substituents. It is shown that the first strategy has little impact whereas the second makes it possible to modulate the electronic properties of the benzene nuclei in the opposite direction to that observed with poly(N-phenylpyrrole).