Consistent and Transferable Force Fields for Statistical Copolymer Systems at the Mesoscale

Abstract

The statistical trajectory matching (STM) method was applied successfully to derive coarse grain (CG) models for bulk properties of homopolymers. The extension of the methodology for building CG models for statistical copolymer systems is much more challenging. We present here the strategy for developing CG models for styrene−butadiene−rubber, and we compare the quality of the resulting CG force fields on the structure and thermodynamics at different chemical compositions. The CG models are used through the use of a genuine mesoscopic method called the dissipative particle dynamics method and compared to high-resolution molecular dynamics simulations. We conclude that the STM method is able to produce coarse-grained potentials that are transferable in composition by using only a few reference systems. Additionally, this methodology can be applied on any copolymer system.

Perspective: Advances, Challenges, and Insight for Predictive Coarse-Grained Models

“…As discussed earlier, they hypothesized that the Fisher information metric could be used to identify maximally informative ensembles for improving the transferability of bottom-up models. Finally, Malfreyt and co-workers recently developed an analogous extension of the statistical trajectory matching method in order to parametrize transferable potentials for CG models of copolymer systems …”

“…Finally, Malfreyt and coworkers recently developed an analogous extension of the statistical trajectory matching method in order to parametrize transferable potentials for CG models of copolymer systems. 372 One expects that LD potentials may also significantly improve the transferability of bottom-up models across mixture compositions. 335,340,344 In particular, bottom-up models with LD potentials quite accurately describe the liquid−liquid phase separation of benzene and water mixtures in two-phase regions of the phase diagram.…”

Development of anisotropic force fields for homopolymer melts at the mesoscale

“…Thermalization and the effect of fast degrees of freedom on the dynamics are obtained thanks to a Dissipative Particle Dynamics (DPD) thermostat. The parameters of the tabulated non-bonded force, of the bonded interactions and the friction are obtained using the bottom-up method called Statistical Trajectory Matching (STM) 40,[46][47][48] . This is the first time this method is applied to the BOA model.…”

“…The parameters of the CG model are obtained using the STM method 40,[46][47][48] . The purpose of the article is not to promote this method with respect to al- ternative older methods (iterative Boltzmann inversion, force matching,...).…”