초록 |
Synthesis of bottblebrush polymer with high grafting density has been in the scope of recent block copolymer studies. In this project, we present inducement of microphase structures perpendicular to the substrate without any surface treatment by implementing bottlebrush polymer with random sequences in the sidechain. Perpendicular orientation of block copolymer is crucial in order for it to be applied to various lithographic areas. Using sequential RAFT polymerization and hydrolysis, PS-b-PMAA was synthesized. As the additive for the surface enrichment, bottlebrush PS-r-PMAA block copolymer was synthesized by RAFT polymerization and ROMP. Using a norbornene-PS-r-PMAA macromonomer, we made the bottlebrush polymer with nearly 100% grafting density. Blending bottlebrush polymer with linear diblock copolymer, surface enrichment of bottlebrush polymer was induced with entropy-dominated thermodynamics. The perpendicular orientation as proved by SEM and GI-SAXS. |