| 초록 |
The effects of the selectivity of toluene/ethanol mixtures on the micellar and ordered structures of asymmetric PS-b-P4VP in the dilute, semidilute, and concentrate solutions, as well as in the solid state, were studied using SAXS, GIFT and TEM methods in order to clarify not only the influence of the nature of the block-selective solvent but also the block copolymer asymmetry on the morphologies of the resulting micelles and the final solid-state structures after evaporating solvents. We studied two asymmetric block copolymers for longer PS block and longer P4VP block. The increase of solvent selectivity caused not only the systematic transition from spherical, to cylindrical and to vesicular micelles, but also the various solid-state structures such as bcc, fcc, lamellar ones when they were dried up. Through this study, we suggested a new method for controlling morphologies of diblock copolymer by using simple mixing two solvents which have different selectivity to each block. |
