Smart Nanofibers Self-Assembled from Dumbbell-Shaped Rod Amphiphiles

摘要

This report covers efforts directed toward self assembly of rod-coil block molecules for use as smart nanofibers. A carbazole end-capped rod amphiphile was synthesized and observed to self-assemble into non-chiral fibers in both methanol and water solutions even though the molecule contains chiral oligoether side groups. A mixture solution of water and methanol induces supramolecular chirality of the nanofibers caused by conformational change of hydrophobic aromatic rods and reduction in hydrodynamic volume of ethylene oxide. The helicity induction of the nanofibers also takes place by heating the water solution. Furthermore, the helical fibers in aqueous solution were observed further aggregate into a rigid gel at higher temperature by enhanced hydrophobic interactions between oligo(ethylene oxide) dendrons.