| 초록 |
The control of block copolymer nanostructure has been extensively investigated using electric field, polymer film thickness, thermal gradient and so on. The block copolymer consisting of different polarity blocks has expected to provide the selective sites for doping dyes which absorb the light with near infrared wavelength. In the areas exposed by near IR laser beam the block copolymer film can melt locally due to the heat generated from the dyes which can transform the photon energy into the phonon energy. Therefore, the slow laser beam writing induces the directional melt-rephase separation to control the nanostructures of block copolymers. For this purpose we employed a polystyrene-b-poly4vinylpyridine (PS-b-P4VP) block copolymer which forms the micelles in toluene having PS corona and P4VP core in order to dope near IR dyes selectively. We used several dyes such as squarylium, manganess(Ⅱ) phthalocyanine and rhodamine 6G. The selective doping of the dyes in the block copolymer nanostructure was confirmed by the large blue shift of the maximum absorbance peak (∆λ∼100nm) observed when the dyes were dissolved with block copolymer micelles. The shift was attributed to the absorption band gap change by the coordination of nitrogen atoms in the P4VP block with the dye molecules. The thin film morphology of the dye doped PS-b-P4VP block copolymer was investigated by AFM and TEM. Laser beam writing on the film allows us to control the orientation of the block copolymer nanostructure. |
