Lifshitz points in blends of AB and BC diblock copolymers
Department of Physics and Astronomy and Polymer IRC, University of Leeds - Leeds LS2 9JT, UK
2 School of Chemistry, University of Leeds - Leeds LS2 9JT, UK
Accepted: 5 November 1998
We consider micro- and macro-phase separation in blends of AB and BC flexible diblock copolymers. We show that, depending on architecture, a number of phase diagram topologies are possible. Microphase separation or macrophase separation can occur, and there are a variety of possible Lifshitz points. Because of the rich parameter space, Lifshitz points of multiple order are possible. We demonstrate Lifshitz points of first and second order, and argue that, in principle, up to 5th-order Lifshitz points are possible.
PACS: 83.70.Hq – Heterogeneous liquids: suspensions, dispersions, emulsions, pastes, slurries, foams, block copolymers, etc / 64.60.Cn – Order-disorder transformations; statistical mechanics of model systems / 83.80.Es – Polymer blends
© EDP Sciences, 1999