Speaker: Christian Linder, Assistant Professor of Civil and Environmental Engineering, Stanford
Title: Stretchability by Design - Advanced Computational Methods to Understand Mechanical Phenomena in Microarchitectured Soft Materials
Abstract: The weakness of conjugated polymers, the basic material for organic semiconductors, is that they are not stretchable. While generally flexible, their stretchability is restricted up to a few percent and at large deformations, cracks can deteriorate electronic device performance. This weakness limits their use in industrial applications that require large stretchability of 100% and new applications demanding complete flexibility. This presentation will show advanced computational simulations to predict the development of a highly stretchable semiconducting material by modeling the blending process of a conjugating semiconducting polymer with an elastomer, thereby triggering nanoconfined morphologies due to phase separation. It will be shown in detail, how advanced computational scale bridging techniques can provide insight on the complex mechanisms involved in that process. In particular, a Cahn Hilliard framework to model morphology evolution in polymer blends, homogenization techniques to understand elastic and inelastic effects in polymers, and a computational framework to account for crystallization based enthalpic effects will be covered in this presentation.
Bio: Professor Christian Linder is the principal investigator of the Micromechanics of Materials Lab at Stanford University. The lab advances modeling aspects, numerical algorithms, and visualization tools to improve the performance and reliability of simulations to (i) understand physical mechanisms in materials, (ii) create innovative sustainable building materials and structures, and (iii) enable upscaled devices and engineered systems of the environment. In-house (iv) computational method development in the area of Computational Mechanics and Computational Materials Science constitutes the foundation of our research.
Professor Linder received his Ph.D. in Civil and Environmental Engineering from UC Berkeley, an MA in Mathematics from UC Berkeley, an M.Sc. in Computational Mechanics from the University of Stuttgart, and a Dipl.-Ing. degree in Civil Engineering from TU Graz. Before joining Stanford in 2013 he was a Junior-Professor of Micromechanics of Materials at the Applied Mechanics Institute of Stuttgart University where he also obtained his Habilitation in Mechanics. Notable honors include a Fulbright scholarship, the 2013 Richard-von-Mises Prize, and the 2016 NSF CAREER Award.