Synthesis, Characterization and Applications of Multi-component and Multi-functional Composites with Nanostructured Conducting Polymers

Abstract

Multi-component and multi-functional nanostructured conducting polymer (CP) based composites were prepared through different methods to obtain materials with academic and industrial interest gathering properties. In two different studies; facile, simple and one-step seeding template-assisted oxidative polymerization reactions of CPs were conducted to synthesize nanocomposites made up of poly(ortho-toluidine) (POT) and polyaniline (PANI) nanofibers (NFs) decorated with different metal (Au/Cu, Ag) nanoparticles (NPs). Enhanced bio-sensing property for glucose and excellent antibacterial activity against both Gram-positive and Gram-negative bacteria strains were meant to be exhibited by these nanocomposites, respectively. As the reaction media, three different metal salts’ aqueous solutions were used. Gold (I) chloride (AuCl), copper (II) chloride (CuCl2) and silver nitrate (AgNO3) salts were, individually, dissolved in DI water to prepare their solutions used in two different studies. They eliminated the extra use of harsh chemicals like hydrochloric acid (HCl), oxidative agents like ammonium peroxydisulfate (APS, (NH4)2S2O8) and also large amounts of in/soluble templates like zeolites, opals and surfactants by acting both as the dopant and oxidant for POT and PANI. Vanadium pentoxide (V2O5) sol-gel NFs were assisting these reactions not only as well-known seeding agents to ensure the NF morphology formation for the resulting CPs, but also as the auxiliary oxidative agents to enhance the overall oxidative potential of the reaction solutions. In the third study, nanostructured CPs, e.g. polypyrrole (PPy) NPs, were used as the microwave absorbing coating on the surface of devulcanized ground tire rubber (dGTR) particles to grow carbon nanotubes (CNTs) on their surface via previously studied “PopTube” approach. Throughout this study; (i) GTR waste was initially devulcanized by short-term microwave irradiation in 4 min., and the virgin rubber ingredient inside them was effectively collected by extraction to be used for the manufacturing of new rubber products, (ii) and then value-added, CNT decorated dGTR particles were also produced as the promising reinforcing agents to make advanced polymeric composite structures. The goal of all these studies was to build a substantial background for different industrial applications, i.e. non-enzymatic/amperometric glucose sensors, excellent antibacterial agents and promising reinforcing agents for polymeric composites, by utilizing the knowledge gained from the chemical synthesis reactions and the instrumental characterizations. In order to investigate, control, improve and characterize numerous properties of CP-based nanocomposites and to determine the effects of different reaction parameters on the final product morphology and properties, the above mentioned projects were undertaken in details throughout this dissertation.