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Multi-scale coarse-graining of diblock copolymer self-assembly: from monomers to ordered micelles

Carlo Pierleoni·Chris Addison·Jean-Pierre Hansen·Vincent Krakoviack
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Abstract

Starting from a microscopic lattice model, we investigate clustering, micellization and micelle ordering in semi-dilute solutions of AB diblock copolymers in a selective solvent. To bridge the gap in length scales, from monomers to ordered micellar structures, we implement a two-step coarse graining strategy, whereby the AB copolymers are mapped onto ``ultrasoft'' dumbells with monomer-averaged effective interactions between the centres of mass of the blocks. Monte Carlo simulations of this coarse-grained model yield clear-cut evidence for self-assembly into micelles with a mean aggregation number n of roughly 100 beyond a critical concentration. At a slightly higher concentration the micelles spontaneously undergo a disorder-order transition to a cubic phase. We determine the effective potential between these micelles from first principles.

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Carlo Pierleoni, Chris Addison, Jean-Pierre Hansen, Vincent Krakoviack. 2006-01-18. Multi-scale coarse-graining of diblock copolymer self-assembly: from monomers to ordered micelles. https://doi.org/10.1103/physrevlett.96.128302

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