| 초록 |
We studied self-organization of rod-coil diblock copolymers for their thin films with a range of thicknesses smaller than or close to the molecular dimension of the copolymer. The copolymer investigated is a diblock copolymer of polystyrene (PS) and poly(3-(triethoxysilyl)propyl isocyanate) (PIC). The molecular weight of the copolymer is 62,000 (PIC, 23K ; PS, 39K) with Mw/Mn of 1.25. The copolymer was coated on the Si wafer by the dip-coating or casting method from its dilute solutions in the concentration of 0.1∼10 mg/mL in tetrahydrofuran. We obtained about 5 nm-thick monolayered block copolymer films from the concentrations lower than 5 mg/mL. The monolayer consists of the PS brushes topped on the bottom PIC layer which is in contact with the surface. As the concentration was increased above 5mg/mL, bilayers with thickness of about 10 nm formed. On the atomic force microscope, the bilayer showed alternating PS-PIC stripe morphology with a periodicity of 60nm. We will discuss further the relationship between the film thickness and the microphase-separated structure of the rod-coil block copolymer. |
