Dissipative particle dynamics for directed self-assembly of block copolymers

Area of Science:

• Soft Matter Physics
• Computational Materials Science
• Polymer Science

Background:

• Dissipative Particle Dynamics (DPD) is a powerful simulation tool for soft matter self-assembly.
• Existing DPD models struggle to accurately represent block copolymer (BCP) behavior in thin films and directed self-assembly.
• Accurate modeling is crucial for understanding and controlling BCP nanostructures.

Purpose of the Study:

• To extend the applicability of DPD simulations for BCPs to thin films and directed self-assembly.
• To develop a reparameterized DPD model capable of predicting complex BCP phase behaviors.
• To provide a computational tool for systems challenging for self-consistent field theory.

Main Methods:

• Reparameterization of the dissipative particle dynamics (DPD) simulation method.
• Application of the reparameterized DPD model to block copolymer (BCP) systems.
• Validation against experimental results for thin films and directed self-assembly.

Main Results:

• The reparameterized DPD model successfully reproduces bulk BCP phase behavior.
• The model accurately predicts experimentally observed thin-film structures from chemoepitaxy and graphoepitaxy.
• Complex structures like bilayer nanomeshes, 90° bends, circular cylinders/lamellae, and Frank-Kasper phases were reproduced.

Conclusions:

• The reparameterized DPD model significantly enhances the predictive power for BCP self-assembly in confined geometries.
• This advanced DPD approach is particularly valuable for complex BCP systems and directed self-assembly scenarios.
• The model serves as a robust tool for predicting and designing nanostructures in thin films.