Phase Diagram of Hierarchical Structures Formed from A(BC)2B Multiblock Copolymers

Abstract

AbstractDue to more than two length scales properties, hierarchical structures, which can combine several properties and respond to multi external conditions, have attracted the continuing attention over the past decades. The corresponding phase diagram of different hierarchical structures is crucially important for the observation of these morphologies. In this paper, the phase diagram of these hierarchical structures in A(BC)2B multiblock copolymer is calculated, including hierarchical lamellae, hierarchical cylinder, and hierarchical sphere (also termed as onion‐like sphere), leading to the identification of the correspondingly stable region. Interestingly, as end block fA increases, the hierarchical phase transition sequence at low χBCN, which is D→S3→C3→L5→L3→C→S→D, is different from that at larger χBCN (LB/C→S3→L5→L3→C→S→D), where lamella formed by B and C blocks is the dominated phase at small A volume fraction. In addition, the perpendicular lamellae at much higher χBCN are observed, which are consistent with the experimental observation of perpendicular lamellae. Importantly, this phase diagram has great guidance for the experimental observation of different hierarchical nanostructures.