Summary: | 碩士 === 國立臺灣大學 === 高分子科學與工程學研究所 === 100 === We use self-consistent mean field theory to investigate changing Flory-Huggins parameter XBC and alternating block number(n) affect the structure under soft confinement by poor solvent, and analyze the micelles surface shape by spherical harmonics. In alternating block copolymer system, increase of XBC gives rise to one dimension ordered lamellar arrangement. The solvent will diffuse into the lamellar region to buffer repulsive force and cave in the surface. The second order spherical harmonics is sufficient to describe the surface shape when two blocks mixed in the micelle. Thus surface shape is similar to one dimension extended ellipsoids. What we are interesting is that the higher order spherical harmonic coefficient is needed when two block separated into lamellar structure inside the micelles. When more solvent molecular diffuse into the lamellar structure, the more irregular surface shape the micelles will be, and lower order spherical harmonics is enough to fit. The less solvent in lamellar structure the less cavity on the surface of micelles, and higher order spherical harmonics coefficient is necessary to describe the delicate cavity.
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