Multiscale Simulation of SU8 and SU8-Graphene Nanocomposite: Bridging Atomistic to Macroscale Peridynamics

SU8 is commercial epoxy-Novolac resin, a negative tone photoresist with outstanding mechanical properties. Its nanocomposites have also been considered as a research material. In order to obtain insights about the SU8 nanocomposites with graphene the present work was conducted to simulate the mechanical properties using multiscale simulation method: atomistic, meso and macro scales. This has started from molecular dynamics, then moved to coarse grain and finally reached to macroscale. Peridynamics is the methodology which is governed throughout the work. Top-down and bottom-up loop has to be employed in order to confirm the total results. A tensile deformation is applied to a 2D plane at the upmost scale to result in an internal pressure. This is transferred to the lower scale in the next step as the external pressure. The procedure continues down until the molecular scale is reached. However, bottom-up strategy requires a bridging model to link the molecular scale to upper scales. The check point is the deformation values which have to be in the same order independent of top-down or bottom-up movement. At 2.1 wt.% of graphene in SU8, increased Young’s, bulk and shear modulus were calculated (62, 200, and 82 % respectively) compared to the neat SU8.