| 학회 | 한국고분자학회 |
| 학술대회 | 2005년 가을 (10/13 ~ 10/14, 제주 ICC) |
| 권호 | 30권 2호 |
| 발표분야 | 고분자 구조 및 물성 |
| 제목 | Nanostructures of Diblock Copolymers in Anodized Aluminum Oxide Templates: Dependence of Nanopore Regularity |
| 초록 | Diblock copolymers composed of two different polymers spontaneously assemble into periodic nanostructures. In bulk, spherical, cylindrical, and lamellar nanodomains are typically observed, depending on molecular weights and compositions of copolymers. If diblock copolymers were confined in the length scale comparable to the period of nanodomains, their morphology, periodicity, and orientation are strongly affected by the geometry and affinity of confinement. We investigated nanostructures of diblock copolymers confined in nanopores of anodized aluminum oxide, AAO. Polystyrene-poly(4-vinyl pyridine), PS-PVP, diblock copolymers were employed, PVP blocks of which have a strong affinity to AAO. Copolymers were confined in different sizes of circular AAO pores. Commercially available AAO membranes provided irregularly-shaped pores. PS-PVP films cast from DMF solutions were placed on the bottom of AAO membrane under weights for good contact and were annealed at 210°C for 24 h under vacuum. After annealing, the AAO membrane was removed by 5.0 wt% aqueous sodium hydroxide solutions. PS-PVP nanorods replicated from the nanopores of AAO membranes were formed on the top of the film. Confined nanostructures of PS-PVP diblock copolymers were directly visualized by transmission electron microscopy, TEM. PVP blocks were selectively stained with iodine for the contrast in TEM. Regardless of bulk morphologies of PS-PVP copolymers, preferential wetting of PVP blocks to AAO was observed. With PS-PVP copolymers forming lamellar nanodomains in bulk, concentric cylindrical morphology along the axis of pores, so-called dartboard morphology, was induced by the confinement. However, the irregularity in circular pores of AAO disturbed formation of the concentric morphology. We also investigated the nanostructures of cylinder-forming PS-PVP in AAO templates. Figure 1. TEM images: (a) concentric lamellae in circular nanopores; (b) non-concentric lamellae in irregularly shaped nanopores. |
| 저자 | 전승민, 김세희, 차국헌, 손병혁 |
| 소속 | 서울대 |
| 키워드 | Block copolymer; AAO; confinement; regularity |
