PME Thesis Defense: Jorge Ayarza

<b>Piezoelectrically-mediated mechanochemical reactions for adaptive polymeric materials</b><br /><br />

Synthetic polymeric materials are usually subject to continuous mechanical stress, which eventually leads to degradation, bond breakage, and failure. Although mechanical energy is constantly being transmitted through the material, it is rarely harnessed for constructive or adaptive purposes. In contrast, biological materials display great adaptability to their environment, as is the case of bones and muscles which can adapt in response to mechanical stimuli by changing their composition and structure. These cellular systems efficiently convert mechanical stress into chemical signals that can drive reactions leading to structural changes, deposition, and removal of material. These adaptive properties give them great advantage in terms of efficiency and durability. Currently, synthetic polymeric materials mostly lack similar adaptability, resulting in mismatches in their physical properties and the need to replace them repeatedly. Materials with adaptive capabilities triggered by mechanical stimuli could significantly extend their life-cycle and boost performance. Piezoelectrically-mediated chemistry is an emergent area of interest for this purpose since mechanical vibrations can be harvested and directly converted to chemical energy. My work revolves around the use of piezoelectrochemistry to conduct mechanically-promoted polymerization and crosslinking reactions using ultrasound and mechanical vibrations as stimuli. Additionally, we present novel strategies to incorporate those chemistries to design adaptive polymeric composites. We envision these methods could find applications in structural materials, robotics, and prosthetics.

<a href="https://uchicago.zoom.us/j/94195421456?pwd=T2w0NXRBbVR2R0cxeUJDWXlnbkhP… Link</a>