Time-resolved Large Strain Rheology of Biopolymer Composites: From experimental characterization to Molecular Dynamics simulation models.

A benefit of composites is the enhancement of mechanical properties beyond a simple linear combination of the mechanical properties of the constituent components. The development and advent of tools and techniques such as three-dimensional cell culture and 3D bio-printing requires a comprehensive pluri-disciplinary understanding of biocomposite materials as their mechanical properties must adequately match pre-defined specifications such as replicating in-vivo conditions. We have synthesized interpenetrating crosslinked fibrinogen and gelatin composite networks that exhibit highly nonlinear rheology through a careful tuning of the concentration and polymerization conditions. In previous talks, we discussed the experimental results that utilize our novel analysis technique derived from the Sequence of Physical Processes (SPP) framework, a time-resolved analysis paradigm for the interpretation of Large Strain Amplitude Oscillatory Strain (LAOS) rheology. In this talk, we will extend our physical understanding of the microscopic origin of the bulk mechanical response of these networks through large-scale Molecular Dynamics simulation. This model system allows us to control microscopic interactions between components as well as modify preparation protocols with the aim to provide a one to one comparison between experimental and in-silico rheology. Additionally, we have access to information allowing the observation of potential structural changes and dynamics at different lenthscales beyond the capabilities of experimental characterization.