Computer-aided tuning of silica/poly(dimethylsiloxane) composites for 3D printing process: A computational and experimental study

Abstract

Additive manufacturing (AM) technology is increasingly used to create customized items and components with complex geometries that were previously unattainable. The challenge is to design polymer-based feedstocks suitable for AM processes, controlling the inks' rheological properties and complicated formulation chemistry. Here we report silica/polydimethylsiloxane(PDMS) inks with optimized rheological properties, tailored through solubility parameters and intermolecular interactions via molecular dynamics simulations. We found that the surface characteristic of silica affects the miscibility between components in the ink formulation, showing a similar trend for both computational and experimental results. With the assistance of molecular dynamics, quantifying the yield stress of inks allowed us to design appropriate ink formulations offering 3D printability without sagging issues during the printing process. Our results demonstrate that the hierarchical calculations from simplified models for solubility parameters to mixed-layer models for interaction energy and dynamics behavior successfully support experimental design to conceive optimized PDMS-based 3D printable ink formulations.