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Ordering and stability in conducting polypyrrole

journal contribution
posted on 30.04.1998, 00:00 authored by K Cheah, Maria ForsythMaria Forsyth, V T Truong
X-ray diffraction (XRD) was employed to characterize electrochemically synthesized polypyrrole (PPy) films with 1,5-naphthalene disulfonate (1,5-NDS) counterions treated with simple acid and base. Results show that the as-synthesized film is amorphous with short-range ordering in the polymer backbone. This ordering is soon lost after thermal ageing at 150°C for 60 days and there is evidence of counterion degradation. Base treatment of the PPy/1,5-NDS films has similar effects leading to a complete loss of ordering in the polymer backbone and dedoping of the polymer. Acid treatment at high temperatures increases the ordering of the polymer backbone and results in the development of a secondary interdopant peak confirming that ion exchange has occurred. Conductivity of the PPy was also increased substantially. The enhanced ordering was maintained even after thermal ageing. Room-temperature acid treatment also results in improved ordering of the polymer as well as the counterion but the increase in conductivity is only marginal and most of the ordering is soon lost after thermal ageing. Increase in ordering of the polymer structure seems to lead to better conductivity, although not necessarily improved thermal stability.

History

Journal

Synthetic metals

Volume

94

Issue

2

Pagination

215 - 219

Publisher

Elsevier S.A.

Location

Basel, Switzerland

ISSN

0379-6779

Language

eng

Publication classification

C1.1 Refereed article in a scholarly journal

Copyright notice

1998, Elsevier Science S.A.