Segmental distribution of polystyrene blocks in lamellar microphase-separated poly(styrene-block-2-vinylpyridine) (SP) with wide composition distribution was investigated by neutron reflectivity measurements using deuterium-labeled polymers. Block copolymers with wide composition distribution were produced by mixing three monodispersed parent block copolymers, which were synthesized by an anionic polymerization method to have the same total molecular weight but with different volume fractions. The block copolymer blends whose overall S/P ratio is 0.5/0.5 were found to form a uniform lamellar structure, where lamellae were highly oriented along the direction parallel to the film surface and the interfacial thickness was evaluated as 40 Å. It was clarified that a shorter block chain in the microdomain is localized at the domain boundary, while a longer one has a peak at the center of microdomain in its segmental distribution profile.
All Science Journal Classification (ASJC) codes
- Electronic, Optical and Magnetic Materials
- Condensed Matter Physics
- Electrical and Electronic Engineering