Synthesis and characterization of pi-conjugated polymers utilizing A-B monomers

Although the initial interest in conjugated polymers was due to their ability to conduct electricity, the current interest in these materials has shifted toward the development of advanced materials with tailored optical, structural and electrical properties. Unfortunately, research on conjugated polymers is hindered by the limited solubility of the materials. This dissertation describes steps taken toward the synthesis of soluble members of the poly(p-phenylenebenzobisoxazole) (PBO) and polyazomethine (PAM) classes.; Initially the synthesis of substituted PBOs via the AA/BB type condensation polymerization of substituted terephthalic acid and bis amino-phenols was investigated. The synthesis of the monomers was successful, however all attempts to synthesize the target polymers failed due to the limited solubility of the substituted terephthalic acids in the polymerization medium. To eliminate the problems experienced due to the limited solubility of terephthalic acids, the synthesis of PBO via A/B, or head-to-tail condensation polymerization, was investigated. To this end the synthesis of the AB monomer 4-(5-hydroxy-6-nitrobenzoxazo-2-yl)-benzoic acid was investigated. Ultimately this endeavor was unsuccessful. However, the synthesis of several new phenyl-benzoxazole derivatives is reported herein.; The final section of this research describes the synthesis of several novel PAMs via head-to-tail condensation polymerization. The attachment of a long side chain in the case of poly (2-dodecyloxy-5-methoxy-p-aminobenzaldehyde) resulted in the formation of polymer that was soluble in a variety of organic solvents, allowing for structural confirmation via NMR spectroscopy.