Thermal and spectroscopic characterization of polypyrrole formed in zeolite Y

Abstract

Encapsulation of pyrrole in two kinds of zeolite Y (NaY and USY) with various concentrations of Cu^II ions has been attempted by a gas diffusion process, and the products have been characterized by means of thermoanalytic and spectroscopic methods. From the results, it was found that the progress of polymerization depended on the Cu^II content, i.e. pyrrole was encapsulated as polypyrrole in both NaY and USY with a high concentration of Cu^II ions, and predominantly as pyrrole oligomer and/or monomer in those with a low concentration of Cu^II ions. Furthermore, EPR spectra revealed that NaY with a high concentration of Cu^II ions was active for the formation of bipolaron polypyrrole in the framework, whereas USY with a high concentration of Cu^II ions was not.