To investigate the phase separation behaviors of immiscible polymer blend, Polystyrene (PS) of Mw=2514 and Polyisoprene(PI) of Mw=2700 were chosen as model compounds for a binary blend pair. A time-resolved light scattering apparatus was employed for the investigation. Cloud points were obtained experimentally and the phase diagram was drawn from them using the Flory Huggins lattice theory and the interaction parameter was also obtained. Sample was heated at one-phase region and then quenched to two-phase region. Progress of separation with time was observed and the results were analyzed by the scaling law. It was found that the separation behaviors observed in this study corresponds to the late stage. It was also found that there were good agreements, even though in a semi-quantitative sense, between the experimental results and a theory predicted by Lifshitz and Slyozov.

비상용성 이성분계 고분자 블렌드의 상분리 현상을 연구하기 위하여 분자량이 2500인 폴리스티렌(PS)과 2700인 폴리이소프렌(PI)을 택하였다. 상분리 현상은 자체 제작한 광산란 장치를 사용하였다. 먼저, 블렌드의 cloud point를 측정하고 Flory-Huggins의 격자이론에 근거한 상평형도와 상호작용매개변수를 구하였다. 상평형도의 단일상 영역에서 가열된 시편을 상분리가 일어나는 온도로 급냉시켜 상분리를 유도한 후 시간경과에 따른 상분리 진행과정을 추적하였다. 실험결과를 scanning analysis를 통하여 분석하여 관측된 상분리 과정이 나중 단계에 해당함을 밝혔다. Lifshitz와 Slyozov가 제안한 이론을 이용하여 실험결과를 분석하였다.

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