| 학회 | 한국고분자학회 |
| 학술대회 | 2005년 가을 (10/13 ~ 10/14, 제주 ICC) |
| 권호 | 30권 2호 |
| 발표분야 | 고분자 나노구조와 물성 |
| 제목 | Isotropic Process of Rod-Coil Molecules in the Random Micelle Regime |
| 초록 | We have investigated the isotropic mechanism of rod-coil molecules in the structure of random micelle. Random micelle phase was observed between body centered cubic and isotropic melt over the wide temperature range (90 ℃~120 ℃) by Differential Scanning Calorimetry (DSC) and small angle X-ray scattering (SAXS) methods. This gradual phase transition is character of random micelle, not shown in other transitions of rod-coil molecules. There are two extreme path ways for the isotropic process; interface diffusion and inter mixing. Similarly, the phase transition from random micellar(disordered micelle) phase to isotropic phase(disordered state) was investigated with coil-coil blockcopolymer by other research groups. In order to know dimicellization mechanism of coil-coil blockcopolymer, size and volume fraction of random micelle which of very asymmetric volume fraction were estimated from form factor and structure factor by SAXS or SANS method. In result, two mechanism were suggested . First, the size of micelles (radius of hard sphere) decreased and volume fraction (hard sphere) was observed without variety with temperature. On the other hand, the size of micelles (radius of hard sphere)was remained unaltered and number density of micelles or volume fraction (hard sphere) decreased. SAXS techniques may give a clue of the isotropic process. Since SAXS intensity contains the intraparticle scattering (form factor) and the interparticle scattering (structure factor), the size and the composition of particles can be evaluated with model assumed. We used the Generalized Indirect Fourier Transformation (GIFT) software developed by Glatter and co-workers to fit the SAXS profiles. In GIFT, there is no model or analytical restriction for form factor, but structure factor is parameterized with up to four parameters for a given interaction model. We used that Percus-Yevick (PY) average hard-sphere model combined with an unconstrained form factor for a polydisperse system. We investigated the isotropic mechanism of rod-coil molecules in the structure of random micelle as compared the DSC results with the size and density of micelles estimated from SAXS |
| 저자 | 이정규1, 박명환2, 이명수2, 진왕철1 |
| 소속 | 1포항공과대, 2연세대 |
| 키워드 | rod-coil molecules; random micelles; SAXS |
