Precise Molecular Design of Complex Polymers and Morphology Control of Their Hierarchical Multiphase Structures

Abstract

This report reviews the recent advances in morphological studies on block copolymer and related multiple component polymer systems that possess characteristic chain connectivity and non-covalent bonding interactions, which were mostly done in our research group. Among many topics, three types of multi-phase systems are picked up and examined in this article. The first system consists of multiblock terpolymers. Hierarchical structures having double periodicity have been formulated for sample polymers including block chains with different lengths. The second one is represented by star-shaped terpolymers of the ABC type, which easily form three-phase cylinder-like structure whose cross sections exhibit periodic tiling structures. They show several Archimedean tilings and one of them forms quasicrystalline tiling with dodecagonal symmetry. The third one is composed of block copolymer/block copolymer blends or a block copolymer/homopolymer blend with hydrogen bonding interactions. It has been found these blends represent very striking phase structures including new mesoscopic tiling structures. These structures with new self-assembly manners due to strategic molecular design open the door to production of many highly functional materials.