Azobenzene-based Supramolecular Liquid Crystal And Small Organic Molecules Gel Study

The self-assembling of small functional molecules into supramolecular structures is a powerful approach toward the development of new materials and nanoscale devices. Liquid-crystalline materials have been applied to optical information display and storage devices because the modulation of the molecular alignment of the liquid-crystalline phase can be controlled by external stimuli such as heat, electric fields, and light. Self-assembly materials containing azo linkages have attracted tremendous attention because of their light-induced photo-switchable and elastic properties. As a novel class of self-assembled materials, organogels have received considerable attention in recent years because they can organize into regular nanoarchitectures through specific noncovalent interactions including hydrogen bonds, hydrophobic interactions,π-πinteractions and van der Waals forces. The whole paper contains two parts as following:1. Multiresponsive self-assembled liquid crystals with azobenzene groups1) Here a new approach was reported to realize the reversible bistable liquid-crystalline phase with light and electric field stimuli in a supramolecular azobenzene complex A₃T by self-assembly of a proton donor A and an acceptor T. A₃T has a lower mesophase transition temperature and shows much more sensitivity to both light and electric stimuli than A.2) The A₃T molecular orientation remains even after removing the electric field; thus this kind of complex has potential applications in imaging and data storage.2. Ion trigger complex organic gels with azo groups1) We have designed and synthesized an organic gels with azo groups, which can form stable gels in many organic solutions.2) The surface of gel formed in alcohol can be changed by adding different ion in the gel. The wettability of the xerogel surface can be controlled by addition of ion.