Organic Chemistry Seminar: Addressing Mechanochemistry with Intramolecular Cross-links

Abstract:

Understanding how materials are affected by mechanical stress is central for developing novel and robust materials with extended lifetimes. In this regard, the most fundamental process is the effect of mechanical stress on molecules, where mechanical energy is transduced into chemical energy by scission of chemical bonds, a process called mechanochemistry. While mechanochemical reactions have been abundantly studied, the use of polymer architecture as a motif for polymer mechanics has been mostly unexplored. In this talk, I describe the use of intramolecular cross-links to reinforce the molecular structure and reduce fragmentation due to mechanochemistry. A systematic study changing molecular weights, cross-link density and positioning was carried out to understand how each of these parameters affects the kinetics of the mechanochemical reactions. Importantly, we raised significantly the mechanochemical stability of methacrylate polymers in solution leading to polymers which are virtually invincible to shear  in solution.

Seminar Organizer: Dr. Roman Dobrovetsky