An investigation on the effect of 𝛽-cyclodextrin (CD) in both free and inclusion-complexed forms with a guest anionic metal complex, dioxalatodiaquochromate(III) (DDC), on the characteristics of conducting 2–polyaniline (PANI) is carried out. Four materials, PANI (i.e. PANI–SO4), PANI–DDC, PANI–CD and PANI–CD + DDC were prepared by in situ chemical oxidative polymerization in aqueous H2SO4 at pH 1 and subjected to electrical conductivity and spectral (IR and UV-vis) measurements. DDC and CD when separately incorporated, reduce the conductivity of PANI by about half whilst their inclusion complex CD + DDC enhances it. Spectral characterization reveals that DDC as a dopant and CD as an encapsule exhibit their effects through adverse interaction with imine–amine N centres and benzenoid moiety of PANI. The inclusion complex CD + DDC, on the contrary, functions as a dopant by lying in between the chains and seems to promote the extended conformation of PANI chain and hence the 𝜋-electron delocalization. Exposure of the material to methanol vapour causes a decrease in conductivity in PANI and PANI–CD while an increase in PANI–CD + DDC. This study makes explicit the distinct role of CD as an encapsule and CD + DDC inclusion complex as a dopant in altering the electrical property of PANI.
Volume 45, 2022
Continuous Article Publishing mode
Prof. Subi Jacob George — Jawaharlal Nehru Centre for Advanced Scientific Research, Jakkur, Bengaluru
Chemical Sciences 2020
Prof. Surajit Dhara — School of Physics, University of Hyderabad, Hyderabad
Physical Sciences 2020
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