Mechanics for Polymer Design
116 Upson Hall/B11 Kimball Hall
Sibley School of Mechanical and Aerospace Engineering Colloquium Series
Polymers are ubiquitous due to their wide range of tailorable thermomechanical and transport properties, low density, and low cost. Modern applications demand multifunctionality, adaptability, and careful life-cycle management. My research group is focused on understanding how polymeric material structure leads to macroscale properties and then using that quantitative understanding to tailor the material. In this seminar I will first give an overview of my research program and then focus in on two examples of how we have applied our solid mechanics toolset to advance innovative polymer concepts. Topic 1: Single chain polymer nanoparticles (SCPN) are formed from intra-chain cross-linking of a single polymer chain. These units have potential as the building blocks of polymers where the properties are controlled by the highly tailorable SCPN structure rather than just by the material chemistry. We utilize both molecular dynamics simulations and experiments to investigate the mechanical behavior of a SCPN assemblies as a function of degree of polymerization and cross-linking. Topic 2: Polymer and interface multifunctionality can be designed through the incorporation of chemical groups termed “mechanophores” that have a specific chemical transformation in response to applied force. Mechanophores have been developed that change color, emit light, alter polymer chain contour length, and trigger crosslinking. However, incorporating these force-driven molecules to create stress-driven functions in bulk materials can be tricky. We use a combination of computational, theoretical, and experimental approaches to understand how stress on the bulk scale is converted to mechanophore-scale force to then modify the polymer.