(431b) Accessible DPD Models for Structured Formulations Via Automated and Atomistically-Driven Parameterization

In many formulations, structure is a focal point for design and optimization. Depending on the application, structure can take on different forms–to name a few: emulsified droplets, microphases, micelles and amorphous dispersions. The fine structural detail in a formulated material can be impractical to characterize in the lab, yet essential to its functionality. With suitable models, a computer-aided design approach can facilitate design for these important details that are not otherwise accessible. The formation of structure, by and large, occurs on a spatiotemporal range that is impractical for computational modeling using all-atom simulation. As such, coarse-grained (CG) simulation, in particular dissipative particle dynamics (DPD), is an attractive approach to access the operative time- and length-scales for structured formulations.

The primary barrier to wider utilization of DPD and other CG methods is the effort required to develop a new model from scratch. In this work, we employed a recently-developed tool to make DPD modeling more accessible by automating model parameterization using all-atom simulation. We have used this tool to build models for various types of structured formulations including surfactant micelles, nano-emulsions and microphase-separated copolymers. Using these models, we will show how changes to composition, molecular architecture and chemistry affect the resulting structures. The ability to systematically develop models that are able to capture these relationships in structured formulations represents a significant advancement in the computational design of these materials.