Layer Formation and Annihilation in an Immiscible Polymer Blend in Electric and Shear Flow Fields

Simultaneous observation of morphological change and measurement of shear stress in an immiscible polymer blend of a liquid crystalline polymer (LCP) and a methyl phenyl silicone oil (MPS) were carried out in electric and shear flow fields by using a system combining a rheometer and a confocal scanning laser microscope (CSLM). Under shear flow and no electric field a thin MPS layer with low viscosity was formed between two parallel plates of the rheometer, which reduced the apparent viscosity. When subjected to an electric field the layer was broken, resulting in the viscosity increase. The relationship between the morphology and the rheology was studied in detail.