Micro-Phase Separated Structures of Block Copolymers Having a Semiflexible Liquid Crystalline Main-Chain Polyester Block

作者：Koga Maito^*; Tokita Masatoshi

来源：Kobunshi Ronbunshu, 2014, 71(11): 501-507.

• Main-Chain Liquid Crystalline Polyester
• Block Copolymer
• Micro-Phase Separated Structures
• Smectic Liquid Crystal
• Lamellae
• Spheres
• Semiflexible Segment

The micro-phase separated structures of ABA triblock copolymers comprising flexible amorphous poly(methacrylate) (PMA, A block) and semiflexible liquid crystalline (LC) polyester (B block) with amorphous block volume fractions (phi(am)) ranging from 0.2 to 0.8 were investigated. For phi(am) < 0.52, block copolymers formed lamellar microdomains. The LC segments extended perpendicular to the interface and formed smectic layers parallel to the lamellae. The segments folded within the lamellae, whereas the amorphous segments had dimensions similar to those of in amorphous block copolymers. When phi(am) > 0.68, the LC lamellae divided into cubes, transforming into spheres in the PMA matrix. Our results demonstrate that flexible-semiflexible-flexible block copolymers can change their morphology characteristically by the contour length and flexibility of the semiflexible segment in addition to other factors known for flexible copolymers.

• 出版日期2014