Microscopic density functional theory for monolayers of diblock copolymers

Edyta Słyk; Roland Roth; Paweł Bryk

doi:10.1063/1.5039522

Microscopic density functional theory for monolayers of diblock copolymers

J Chem Phys. 2018 Aug 14;149(6):064902. doi: 10.1063/1.5039522.

Authors

Edyta Słyk¹, Roland Roth², Paweł Bryk¹

Affiliations

¹ Department for the Modeling of Physico-Chemical Processes, Maria Curie-Skłodowska University, 20-031 Lublin, Poland.
² Institute for Theoretical Physics, University of Tübingen, Auf der Morgenstelle 14, 72076 Tübingen, Germany.

PMID: 30111154
DOI: 10.1063/1.5039522

Abstract

We propose density functional theory for diblock copolymers in two dimensions. Our theoretical framework is based on Wertheim's first order thermodynamic perturbation theory. Using the proposed approach, we investigate the structure and phase behavior of monolayers of symmetric diblock copolymers. We find that the phase behavior of symmetric diblock copolymer monolayers is similar to that in 3D. This includes the scaling of the equilibrium lamellar width with chain length. We find that the topology of the resulting phase diagrams depends on the chain length and the unlike segment interaction incompatibility and involves either one, two, or three triple points (one of them being the peritectic point). We expect that a similar phase behavior could be obtained for monolayers of colloidal suspensions with carefully tuned interparticle interactions.