Infrared Investigations of Pristine Polypyrrole - Is the Polymer Called Polypyrrole Really Poly(Pyrrole-Co-Hydroxypyrrole)
Abstract
Polypyrrole (Ppy) is one of the most extensively investigated of the electronically conductive polymers. Nevertheless, there is still much we don't understand about this interesting and useful material. One of the most persistent mysteries involves simple chemical composition. Doped PPy should have the empirical formula C4 H3 NX where X is the dopant counterion and z is the fractional doping level; z is typically on the order of 0.3. However, elemental analyses of PPy typically show empirical formulas like C4 H3 NX(z)Oy where y ranges from 0.3 to 0.7 unaccounted for oxygen atoms per pyrrole ring. This paper presents IR spectral data which suggests that the oxygen in PPy is present as covalently-bound hydroxide. Analogous IR investigations of poly(N-methylpyrrole) films show that this polymer is also hydroxylated. The hydroxy substitution present in these polymers undoubtedly results from nucleophilic attack by water on the nascent polycationic chains.
Document Details
- Document Type
- Technical Report
- Publication Date
- Apr 30, 1992
- Accession Number
- ADA249746
Entities
People
- Charles R. Martin
- Junting Lei
Organizations
- Colorado State University