A Precise Polyrotaxane Synthesizer

NU 2020-106

INVENTORS
James F Stoddart*
Yunyan Qiu

ABSTRACT
Mechanically interlocked molecules constitute one of the first ports of call for designing and synthesizing artificial molecular machines. Although polyrotaxanes have already found niche applications in exotic materials with unique mechanical properties, efficient synthetic protocols to produce them with precise numbers of rings encircling their polymer dumbbells are still lacking. Northwestern researchers have developed an assembly line-like emergence of higher and higher energy poly[n]rotaxanes, by harnessing artificial molecular pumps to deliver rings in pairs by dint of cyclical redox-driven processes. This programmable strategy leads to the precise incorporation of two, four, six, eight and ten rings carrying 8+, 16+, 24+, 32+ and 40+ charges, respectively, onto hexacationic polymer dumbbells, depending precisely on the number of redox cycles applied chemically or electrochemically, in both stepwise and one-pot manners.

APPLICATION

• Precision synthesis of polyrotaxanes, controlling sequence, number of threaded rings, side-rings, and composition of polymers.  For us in shock-absorbing material, sound-absorbing materials, anti-scratch coatings, etc.

ADVANTAGES

• Precise number of threaded rings employing artificial molecular machines
• Variety of polymer backbones, significantly broadening the scope of polyrotaxane architectures

PUBLICATION
Qiu Y, Song B, Pezzato C, Shen D, Liu W, Zhang L, Feng Y, Guo QH, Cai K, Li W, Chen H, Nguyen M, Shi Y, Cheng C, Astumian RD, Li X and Stoddart JF (2020) A precise polyrotaxane synthesizer.  Science.  368: 1247-1253.
 

IP STATUS
A US patent application has been filed.