The purpose of this research was to contribute to the understanding of interactions which may occur between electrically conductive polypyrrole and insulating polymeric substrates. Substrates considered in this work included the fiber forming polymers polyethylene terephthalate (PET), polypropylene and nylon 6,6. Superior adhesion was observed between polypyrrole and nylon 6,6. Determination of the nature of this interaction was the primary objective of this project.; To the best of my knowledge, the first chemically produced homogeneous blends of polypyrrole with a matrix polymer are reported in this dissertation. Blend films were produced by polymerization of pyrrole monomer in a solution of nylon 6.6 and ferric chloride oxidant in formic acid. The solution of polypyrrole and nylon 6,6 appears to be a true solution and may be the first report of a soluble polypyrrole system in which the polypyrrole is unmodified. The films are visually uniform, smooth and opaque black. Scanning electron microscopy provides no evidence of phase separation in the blends even after tensile stress.; Infrared spectroscopy of the films revealed evidence for hydrogen bond interaction between doped polypyrrole and nylon 6,6. The N-H stretch of nylon 6,6 was shifted indicating hydrogen bond interaction. X-Ray diffraction indicated this shift was not due to crystallinity of the blend. These films were also shown by Instron tensile tests to have reasonable mechanical properties and may be drawn over 150%. The films were also found to be conductive. Conductivity was reported at 16% by weight loading of nylon 6,6 with polypyrrole. Incorporation of polypyrrole increased the conductivity of nylon 6,6 by ca. 12 orders of magnitude. Conductivity was shown to increase with drawing regardless of draw ratio. There also appears to be a correlation between draw ratio and increase in conductivity. This suggests alignment of polypyrrole chains upon drawing which supports homogeneous blending of polypyrrole with nylon 6,6. It was found that the blend films do not redissolve in the solvent from which they were originally cast (formic acid) which also supports strong interaction between the two constituent polymers.; A potential mechanism was proposed to account for hydrogen bonding between amide N-H groups in nylon 6,6 and an electron-rich site in polypyrrole which is supported by infrared spectroscopic evidence. The mechanism is as follows: The amide protons in nylon 6,6 hydrogen bond with the lone pair of electrons on pyrrole nitrogen which becomes available upon conversion of polypyrrole from aromatic to the conductive quinoidal form.
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