Shear induced alignment in a model of a block copolymer

TL;DR

This paper investigates how shear flow affects the stability and alignment of lamellar structures in diblock copolymers using a mesoscopic model, providing insights into flow-induced morphological changes.

Contribution

It introduces a detailed analysis of lamellar solution stability under shear flow, including steady and oscillatory conditions, which advances understanding of flow-microstructure interactions in copolymers.

Findings

Identified parameter regions where lamellar structures are stable under shear.

Derived nonlinear lamellar solutions for steady and oscillatory shear.

Analyzed stability against long wavelength perturbations.

Abstract

A mesoscopic model of a diblock copolymer is used to study the stability of a lamellar structure under a uniform shear flow. We first obtain the nonlinear lamellar solutions under both steady and oscillatory shear flows. Regions of existence of these solutions are determined as a function of the parameters of the model and of the flow. Finally, we address the stability of the lamellar solution against long wavelength perturbations.