Physics – Condensed Matter – Soft Condensed Matter
Scientific paper
2001-10-14
Macromolecules 35, 5161 (2002)
Physics
Condensed Matter
Soft Condensed Matter
26 pages, 9 ps figures
Scientific paper
10.1021/ma0117716
We examine the alignment of thin film diblock copolymers subject to a perpendicular electric field. Two regimes are considered separately: weak segregation and strong segregation. For weakly segregated blocks, below a critical value of the field, E_c, surface interactions stabilize stacking of lamellae in a direction parallel to the surfaces. Above the critical field, a first-order phase transition occurs when lamellae in a direction perpendicular to the confining surfaces (and parallel to the field) become stable. The film morphology is then a superposition of parallel and perpendicular lamellae. In contrast to Helfrich-Hurault instability for smectic liquid crystals, the mode that gets critical first has the natural lamellar periodicity. In addition, undulations of adjacent inter-material dividing surfaces are out-of-phase with each other. For diblock copolymers in the strong segregation regime, we find two critical fields E_1 and E_2>E_1. As the field is increased from zero above E_1, the region in the middle of the film develops an orientation perpendicular to the walls, while the surface regions still have parallel lamellae. When the field is increased above E_2 the perpendicular alignment spans the whole film.
Andelman David
Tsori Yoav
No associations
LandOfFree
Thin Film Diblock Copolymers in Electric Field: Transition from Perpendicular to Parallel Lamellae does not yet have a rating. At this time, there are no reviews or comments for this scientific paper.
If you have personal experience with Thin Film Diblock Copolymers in Electric Field: Transition from Perpendicular to Parallel Lamellae, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Thin Film Diblock Copolymers in Electric Field: Transition from Perpendicular to Parallel Lamellae will most certainly appreciate the feedback.
Profile ID: LFWR-SCP-O-317654