Highly Oriented Self-Assembly of Conducting Polymer Chains: Extended-Chain Crystallization during Long-Range Polymerization

摘要

We investigated a self-assembly of conjugated polymer chains resulting in crystalline one-dimensional (1D) nanostructures with a high length-to-diameter aspect ratio. Conjugate polymer 1D nanostructures were obtained via a biphase interfacial polymerization method in which aniline monomers were oxidized by metal ions dissolved in aqueous solution. High-resolution transmission electron microscopy (TEM) analyses revealed polymer chains with remarkable π-electron interchain interactions intensive enough to form long crystalline nanowires and nanobelts, which have been difficult to obtain in conjugate polymer nanostructures. The remarkably uniform nanostructures along the long axis indicate the cooperative effects of chain-end oxidative polymerization and close-packing condensation π-electron coupling) between linear chains and the prevention of random cross-linking and coiling of polymer chains. Electrical conductance along the polymer-chain direction of nanowires forming a long ribbon was estimated to be 46 kΩ via a four-probe measurement, suggesting that stable and partially oxidized polyaniline nanostructures can be produced in the presense of Au ions as effective electron acceptors. The resulting products may find potential uses in nanoelectronics and optoelectronic devices where highly uniform and oriented conducting channels are desired.