Observation of Fddd structure in SI diblock copolymer/homopolymer blends
Abstract
We previously reported the discovery of a novel bicontinuous microdomain structure with Fddd symmetry in polystyrene-block-polyisoprene (SI) diblock copolymer. Then we confirmed the stability of Fddd structure and found Fddd structure exists as an equilibrium structure in SI diblock copolymer. Also we determined the stable region of Fddd structure in the phase diagram of SI diblock copolymers. It is well known that blending homopolymer with diblock copolymer causes order-order transition under wet brush condition. We can anticipate that homopolymer - diblock copolymer blend exhibits Fddd structure even though the neat block copolymer does not have Fddd region. In this study, we, hence, investigated the phase behaviors of SI diblock copolymer-PS homopolymer blends with various compositions by small-angle X-ray scattering (SAXS) and transmission electron microscopy (TEM) and explored how blending homopolymer affects the Fddd region. Consequently, we could confirm that addition of polystyrene homopolymer (hPS) induces morphology transformation and determine the region of Fddd phase in the SI diblock copolymer/hPS blends that is similar to that of SI diblock copolymers we reported.
- Publication:
-
APS March Meeting Abstracts
- Pub Date:
- March 2010
- Bibcode:
- 2010APS..MAR.S1049K