(244f) Microphase Separation in Diblock Copolymer Material Driven By Solvent Evaporation

The repulsion of different copolymer blocks is mediated by solvent. This usually lowers the effective Flory-Parameter below the order-disorder transition.
Upon evaporation of the solvent, the repulsion between the blocks increases and drives the microphase separation.
This technique is common in experimental settings but challenging to investigate via computer simulations.

We present models for a soft, coarse-grained polymer that can bridge the required time and length scales of the processes involved.
Challenging is that we are modeling the system with an explicit liquid-vapor interface. From this evaporation front, the order protrudes far into the bulk phase - several extensions of the polymer extensions.
Additionally is the dynamics of the molecules essential to understanding the dynamics driven by the molecular orientation and translation.
We investigate the evaporation process to understand how it can be utilized to guide specific orientations and limit the defect formation in the resulting morphology.