Date of Award

2007

Document Type

Thesis

Degree Name

Master of Science (MS)

Department

Chemistry

First Advisor

Tito Viswanathan, PhD

Abstract

Polypyrrole (PPy) is one of the conductive polymers frequently used in commercial applications, mainly due to its long-term stability and the possibility of forming homopolymers or composites with optimal properties. Polypyrroles were prepared by the chemical polymerization of pyrrole using various methods. The effects of several parameters such as oxidant, dopant type, additives and reaction conditions on the properties of PPy were investigated. In addition, PPy/graphite composites were prepared because graphite is highly conductive and effectively incorporated into the polymer matrix during the polymerization. The amount of graphite in the composite was varied to determine the maximimum conductivity achievable in the composite. Graphite nanosheets were also prepared from pristine graphite by chemical and physical treatment in order to improve dispersion and conducting property of the composite. Since PPy is not soluble in any solvent, the use of lignosulfonate as a dopant was studied to overcome its insolubility. Polymerization was also performed in a heterogeneous biphasic system containing organic and aqueous media in order to improve the solubility of PPy. Characterization methods included conductivity measurement, FTIR spectroscopy, thermogravimetric analysis (TGA) and X-ray diffraction (XRD). Solubility tests were performed to elucidate the relation between the synthetic procedures and composite properties.

Download

Share

COinS