Synthesisand Study Onself-Assembly Properties Of X-Shaped And N-Shaped Rod-Coil Molecules

Nowadays, designing and synthesising novel nanoscale supramolecular structures to fabricate a series of supramolecular constructions are currently one of great interest subjects. In this paper, two series of rod-coil molecules which contains X-shape and n-shape on the rod building block. And self-assembly behavior of these molecules was studied in the bulk and aqueous solution through the POM> DSC^SAXS-. UV and fluorescence spectra.Firstly, X-shaped amphiphilic rod-coil molecules la and lb were synthesized to study the self-assembly behavior. Rod parts are consisted of pyrene and ethinyl biphenyl groups of the π-conjugated structure. Coil parts are made of the polyethylene oxide (PEO) with the6and8repeating units. In bulk state, molecule la has one liquid crystalline phase. In this state, it can self-assemble into rectangular columnar structure. On the room temperature, it can self-assemble into layer structure. In aqueous solution, molecule la and lb both can aggregate into the spherical structure through the AFM study.Secondly, n-shaped amphiphilic rod-coil molecules1,2,3were synthesized to study the self-assembly behavior. Both1,2,3are consisted of anthracene and two ethinyl biphenyl groups. Coil part:molecule1was consisted of polyethylene oxide (PEO) with the5repeating units. With the purpose of studying the influence of the chiral methyl group on the rod and coil interface on the self-assembly behavior, molecule2was synthesized which consists of polyethylene oxide (PEO) with the5repeating units which has the chiral methyl group between the rod and coil segments. On the basis of molecule2, molecule3with lateral butyl group in the center of the rod segment was synthesized to study the influence of the lateral butyl group on the self-assembly behavior. In the bulk state, molecule1,2both show a liquid crystalline phase. Molecule1exhibits layer and HPL structure in the crystalline and liquid crystalline phase, respectively. And molecule2exhibits HPL and rectangular columnar structure in the crystalline and liquid crystalline phase, respectively. Molecule3only has a solid phase with the oblique columnar structure. In aqueous solution, molecule1,2and3all display red shift in the UV-Vis spectra and all intensity of the fluorescence maxima was quenched in the FL spectra. Typical molecule1can aggregate into the rod-like structure through the AFM study.