[Soft Matter]Lyotropic meso-phase behavior of

supramolecular nanotubes with helical charge distribution

Associate researcher Ningdong Huang and PhD student Shenghui Wei in Professor Liangbin Li’s group, used BTA molecules, which are widely used building blocks in the supramolecular system, as research objects to study the relationship between the structure of a primary assembly with spiral charge distribution and long-range ordering. Related research work was published in the recent Soft Matter (2017, 13, 3475-3479).

How to freely control the hierarchical self-assembly structure of the supramolecular polymer is still facing challenges, and it is urgently needed to comprehensively study the driving force involved in hierarchical assembly to achieve the purpose of controlling a hierarchical assembly structure. The unique liquid crystal behavior of a supramolecular polymer system may be related to the helix interactions between them. By studying the mesoscopic phase behavior of supramolecular nanotubes with spiral charge distribution, the effect of spiral charge distribution on hierarchical self-assembly structures can be revealed.

Studies show that the dilute solution of supramolecular charged spiral nanotubes exhibits a rich and unique mesoscopic behavior that can not be explained by traditional liquid crystal phase transition theory (excluding volume effect). The charged supramolecular nanotubes first form a short-range orderly Hexatic structure in solution, and the Hexatic structure can be transformed into a stable, highly positional ordered rectangular phase by increasing the aging time or introducing NaCl. Positional order in the Hexatic structure and in the rectangular phase decreases as the spacing between adjacent tubes decreases. The angular correlation and the relative rotation of the charged spiral nanotubes in the axial direction lead to the above unique phenomena.

This work was supported by the National Natural Science Foundation of China (21574123, 21611130178), Royal Society Newton Mobility Grant MBAG/240 RG82754.

Lyotropic meso-phase behavior of supra-molecular nanotubes with helical charge distribution.