Micro-Meso Scale Model of Electrospun Poly (Ester Urethane) Urea Scaffolds

Abstract

Soft tissue engineering applications require accurate descriptions of native and engineered tissue microstructure and their contributions to global mechanical behavior [1–6]. Moreover, micro scale based mechanical models can be used to: (1) guide tissue engineering scaffold design, (2) provide a better understanding of cellular mechanical and metabolic response to local micro-structural deformations, and (3) investigate structural changes as a function of deformation across multiple scales. We present a novel approach to automatically collect micro-architectural data (fibers overlaps, fiber connectivity, and fiber orientation) from SEM images of electrospun poly (ester urethane) urea (PEUU) to recreate statistically equivalent scaffold mechanical models. More importantly, an appropriate representative volume element (RVE) size was selected to fully capture both critical micro-scale architectural information, as well as reproducing the larger-scale directional long fiber mechanical behavior. This approach produced material models by specifying fiber overlap density, fiber orientation, and connectivity allowing the bulk mechanical response to be determined at the meso and micro scale via FEM simulations.