Accession Number:

ADA239148

Title:

X-Ray Structure of Polyaniline Derivative-Poly-Ortho-Toluidine: The Structural Origin of Charge Localization.

Descriptive Note:

Technical rept. 1 Jan-31 Oct 91,

Corporate Author:

PENNSYLVANIA UNIV PHILADELPHIA DEPT OF CHEMISTRY

Report Date:

1991-08-07

Pagination or Media Count:

24.0

Abstract:

We investigated the structural features of the polyaniline derivative-poly-ortho-toluidine POT. In the base form POT is amorphous, with an x-ray diffraction pattern similar to that of emeraldine base EB-I. We estimate from the position of the broad peaks in the amorphous pattern that the interchain spacing is larger in POT-EB than in EB-I. POT hydrochloride is partially crystalline with a diffraction pattern resembling that of emeraldine hydrochloride ES-I. Analysis of the data shows that the crystalline part of POT hydrochloride adopts the ES-I like structure, with increased zig-zag angle of the polymer chain and larger interchain spacing, together with an increased disorder, possibly due to defects in the stacking of polymer chains caused by the bulky -CH3 groups. Structure and percent crystallinity evolve with doping level in the same way as in the EB-I - ES-I emeraldine system. These structural results correlate with difference in the electronic properties of the POT-ES as compared with ES-I. In particular, the 103 decrease in room temperature conductivity of POT-ES compared to ES-I and concomitant localization of conduction electrons in POT-ES as compared with PAN-ES is attributed to the increased separation and decreased coherence between polymer chains leading to quasi-dimensional localization of conduction electrons.

Subject Categories:

  • Organic Chemistry

Distribution Statement:

APPROVED FOR PUBLIC RELEASE