Phase separation ofum-thickness films of a binarypolymer melt under in-planeelectric fields

• Main Authors: Chen-Hung Wang, 王正宏
• Other Authors: Peilong Chen
• Format: Others
• Language: en_US
• Published: 2006
• Online Access: http://ndltd.ncl.edu.tw/handle/s47a23

碩士 === 國立中央大學 === 物理研究所 === 94 === Polymer blends of PS and PMMA are used to study the time evolution of um-thickness film phase separation of binary fluid mixtures under applied in-plane electric fields. It is found that the phase separation is accompanied by dewetting processes (PS dewet PMMA) at the later stage for weak fields, but the dewetting is suppressed while the electric field is increased. The growth rates of holes for binary um-thickness films agree with the classical thin-film system at the early stage but distinct at the late stage. From the profiles of the dewetting domains and optical images of dewetting processes, we provide a dynamical picture of this dewetting process in this thesis. We also find that the electric field will break the spinodal decomposition structures during phase separation so domains become small, with the dewetting holes disappearing under strong fields. The competition between two instabilities induced by the dewetting and electric field makes the phase separation morphology different at weak and strong fields. The power laws of the growth rates of dewetting holes and domain sizes in final states are measured to compare with the normal phase separation and classical dewetting.