| 초록 |
Diblock copolymers exhibit various nano-scale morphologies such as lamellar, hexagonally packed cylinder, spheres, double gyroid and hexagonally perforated lamellar (HPL) and these phases and the phase transitions have been well established. Recently another network phase, Fddd was experimentally found in bulk and thin film system. It has an orthorhombic unit cell and belongs to the Fddd space group. This phase has the single network skeleton which consists of the minor block domain. And, in thin film, the specific plane is oriented parallel to substrate. In this study, we investigate the thermal phase transition from HPL to Fddd in polystyrene-b-polyisoprene thin film. The grain boundary of coexistence phase is studied using by transmission electron microtomography and grazing incidence small angle X-ray scattering. Both structures consist of trivalent connector, but their configurations are quite different. It makes somewhat change of film geometry at grain boundary. |
