Rotaxanes are a type of mechanically interlocked molecule, consisting of a molecular “dumbbell” threaded through a macrocycle, which can be used as a repeat unit to form larger interlocked polymers (i.e. polyrotaxanes). Since interlocked polymers are primarily composed of mechanical bonds, instead of covalent bonds, the material properties are dominated by component geometry as opposed to chemical structure. Due to the complexity of mechanically interlocked molecules, it is difficult to optimize component geometry by purely synthetic techniques, thereby necessitating the use of an integrated experimental and computational approach. Herein we report the synthesis of a novel double-threaded poly[3]rotaxane by a metal-templating process with the 2,6-bis(N-alkyl-benzimidazolyl)pyridine ligand. Design of the poly[3]rotaxane was supplemented by atomistic simulations used to determine the optimum component geometry to prevent disassembly of the interlocked structure. Further coarse-grained dissipative particle dynamics (DPD) simulations were used to calculate rheological properties of the bulk material in order to understand the relationship between component geometry and material properties. By understanding the structure-property relationships of mechanically interlocked polymers, future materials can be designed more efficiently and with a greater degree of structural control.

Integrated synthetic and computational techniques for the design of poly[3]rotaxanes

251st National Meeting (2016)

The official archive and repository for all ACS Meetings & Expositions abstracts and select posters or presentations.