| 학회 | 한국고분자학회 |
| 학술대회 | 2003년 봄 (04/11 ~ 04/12, 연세대학교) |
| 권호 | 28권 1호, p.19 |
| 발표분야 | 특별 심포지엄 |
| 제목 | Order-order and Order-disorder Transitions of Block Copolymer Solutions Using Small Angle X-ray and Neutron Scattering |
| 초록 | The phase behavior of a symmetric styrene-isoprene (SI) diblock copolymer in styrene-selective solvents, dialkyl phthalate, was investigated by in-situ small angle X-ray scattering (SAXS) on shear-oriented solutions. In particular, when marginally good solvent was used, intriguing morphological change has been observed by varying temperature in a narrow range of polymer concentration presumably due to the reduced repulsive interaction between the microphase-separated domains. When a sphere-forming block copolymer is used, subtle order-order transitions from fcc/hcp to bcc/hcp to hex occur by raising temperature. The epitaxial relationship between hcp and hex is described for the first time in block copolymers, whereas the bcc/hex epitaxy is as previously established. The transition kinetics is also examined by a combination of rheology and static birefringence. The order-disorder transition of PS-b-PI diblock copolymer in solvents of varying selectivity for a specific block is investigated with small angle neutron scattering (SANS). In order to understand the subtle morphological changes more clearly, one of the diblock copolymer is deuteratued (i.e., PS-b-dPI and dPS-b-PI). The change of the core size upon change in temperature is monitored by SANS and the detailed explanation for the order-disorder transition is suggested. |
| 저자 | 박문정;차국헌;Timothy P. Lodge |
| 소속 | 서울대 |
| 키워드 | Phase behavior; styrene-b-isoprene; SAXS; SANS |
