Real-Time Dynamic Impact Strain Deformation Measurements of Transparent Poly(urethane urea) Materials

Abstract : Transparent poly(urethane urea) (PUU) materials with tunable microstructures offer an avenue to enable material designs with desired dynamic mechanical deformation properties. This report presents recent experimental findings of select model PUU materials upon ballistic impact testing. Tailoring the microstructure appears to be a dominant factor in altering the rate-dependent mechanical deformation behavior, while promoting phase mixing gives rise to dynamic strain hardening, which is validated by the real-time 3D strain evolution measurements via digital photogrammetry. These efforts are a part of an ongoing research project focused on investigating the microstructure-property relationships of PUUs, in an attempt to elucidate the molecular mechanisms key to simultaneous improvements in both physical and mechanical properties.