Accession Number:

ADA234599

Title:

Electrochemically Induced Charge and Mass Transport in Polypyrrole/ Poly(styrene Sulfonate) Molecular Composites

Descriptive Note:

Technical rept.,

Corporate Author:

TEXAS UNIV AT ARLINGTON CENTER FOR ADVANCED POLYMER RESEARCH

Report Date:

1991-04-12

Pagination or Media Count:

37.0

Abstract:

Polypyrrolepolystyrene sulfonate PPPSS molecular composites have been synthesized by the electrochemical polymerization of pyrrole in the presence of sodium polystyrene sulfonate PSS-Na. Their synthesis and charge transport properties have been investigated by a combination of electrochemical and gravimetric techniques using the Electrochemical Quartz Crystal Microbalance EQCM. Electropolymerization in water at 0.8 V vs. AgAgC1 yields a partially hydrated polymer complex with sulfonate dopant anions from the PSS. Mass transport is found to be cation specific, as expected for a composite system, with the polyelectrolyte chains physically entrapped within the polymer membrane. Frequency responses of the EQCM during electrochemical switching are found to increase with increasing electrolyte cation mass as Liis equivalent to Na Cs Et4N Bu4N. Chronogravimetric and chronocoulometric analyses of PPPSS-Na yield apparent diffusion constants, Dapp, between 10 to the -9th power and 10 to the -11th power sq cm s for mobile hydrated Na species. Though the determination of theses values are complicated by the exact determination of the concentration of electroactive sites C sub O, it is evident that reductive transport processes are faster than oxidative transport processes during switching.

Subject Categories:

  • Physical Chemistry

Distribution Statement:

APPROVED FOR PUBLIC RELEASE