In this project funded by the Macromolecular, Supramolecular and Nanochemistry Program of the Chemistry Division, Jeffrey S. Moore of the University of Illinois at Urbana-Champaign will develop new force-sensitive molecules (mechanophores) that, under mechanical stress, undergo a series of chemical reactions to produce acid. The research has three complementary components. In the first part, the research will focus on the design and study of cascade reactions, where a mechanochemical reaction leads to a high energy intermediate, which will undergo one or several reactions, eventually producing acid. In the second part, the acid production will be validated by developing analytical methods to study the acid production and the physical and chemical changes in the polymer structure concurrently. Finally, by combining selective mechanochemical acid-generation to acid-catalyzed bond formation, autonomous self-reinforcing materials will be developed. The broader impacts involve training undergraduate and graduate students, postdoctoral researchers, the development of mechanically adaptable polymers and composites with fundamental implications in self-healing applications. The extended service life of components made from these smart materials will contribute to reducing waste generation.
Plastics and composites are ubiquitous in our lives, being the materials of choice for small applications such as cell-phone screens to large ones such as airplane hulls. These materials have a limited lifetime, which can be reduced under mechanical stresses. This research seeks to improve the lifespan of these materials by developing a self-healing system which harnesses the mechanical stress these materials support to reinforce or heal the material. The specific focus is to find a robust way to produce acid under mechanical stress and use this acid for constructive chemistry. Through development of these new processes, this research will lead to the development of intelligent materials with the ability to self-reinforce or even self-heal when under mechanical fatigue.