Nanofiber formation via the self-assembly of a chiral regioregular poly(azomethine)

摘要

An optically active π-conjugated poly(azomethine) can be self-assembled into nanometer-sized fibrous architectures with a unique optical activity in the film state, whereas its corresponding racemic analogue did not show any distinct self-assembling properties.rnNanostructured conducting polymers such as polyaniline, polyacetylene and polythiophene have attracted significant interest in recent years due to their potential applications in semiconductor nanotechnology. The programmed self-assembly of rationally designed polymers is the key strategy to control the morphology of materials at the nanometer scale. For example, the close packing of regularly-arranged alkyl side chains in regioregular head-to-tail coupled poly(3-alkyl-thiophene)s (HT-P3ATs) gives rise to highly ordered lamellar structures, in contrast to the disordered solid phase, which is formed of corresponding regiorandom analogues. Moreover, chiral HT-P3ATs bearing an optically active side group show a unique optical activity, both in solution and in the film state, where they form chiral, supramolecular self-assembled structures based on intermolecular π-π stacking. However, despite the well-known influence of polymer microstructure on the self-assembly of P3ATs, such control of molecular structure has rarely been achieved in other classes of π-conjugated polymers.