Self-assembled structures in block copolymer/graft copolymer blends with hydrogen bonding interaction

The effect of hydrogen bonding on the phase behavior of PS-based block copolymer and poly(styrene-graft-acrylic acid) (PS-g-PAA) blends was investigated. The presence of hydrogen bonding enhanced the compatibility of two copolymers. This caused PS-g-PAA to intervene in the interface between microdomains of the block copolymer. Consequently, an order-disorder transition occurred at a high concentration of PS-g-PAA. On the other hand, poor miscibility and the lack of hydrogen bonding in the blends prevented PS-g-PAA from being incorporated into microdomains of the block copolymer, causing the macrophase separation of two copolymers.