Lamellae Stability in Confined Systems with Gravity

TL;DR

This study uses a cell dynamical system model to investigate how confinement and gravity influence lamellae stability in diblock copolymer melts, revealing key factors for ordered structure formation and interface behavior.

Contribution

It demonstrates the impact of hard wall confinement and gravity on lamellae ordering and interface characteristics in diblock copolymer systems, providing new insights into their stability mechanisms.

Findings

Hard walls are crucial for lamellae ordering.

Lamellae parallel to walls and perpendicular to gravity are most stable.

Gravity increases the interface width in the system.

Abstract

The microphase separation of a diblock copolymer melt confined by hard walls and in the presence of a gravitational field is simulated by means of a cell dynamical system model. It is found that the presence of hard walls normal to the gravitational field are key ingredients to the formation of well ordered lamellae in BCP melts. To this effect the currents in the directions normal and parallel to the field are calculated along the interface of a lamellar domain, showing that the formation of lamellae parallel to the hard boundaries and normal to the field correspond to the stable configuration. Also, it is found thet the field increases the interface width.