| The morphology of a multilamellar polymer blend is a major structure factor which determines its properties. For the difficulty and the importance both in theory and in application, it was highlight in multiphase polymer blend research to study the factors, especially the shape, size and distribution of its dispersed phase, which influences the morphology of a multiphase polymer. As a part of a project subsidized by National Nature Science Fundation, this paper drew some significant conclusions after deep rheological morphology research on HDPE/PETG system and HDPE/UHMWPA system.On the base of a vast amount of experimental data, the morphology developing process in HDPE/PETG blend and HDPE/UHMWPA blend was studied, and laminating mechanism of multiphase polymer blend, four essential conditions and four sufficient conditions for lamination of dispersed phases were put forward. We suggest: in the extruding shaping process of a slice material, the dispersed phase in a multiphase polymer blend is formed through five stages: the melting and crushing of the original pellet, the ellipsoidization of the melted body, the stabilization of the orientated melted body, the lamination of the dispersed melted phase and the axial drawing of the melted slice. The four essential conditions are equally viscosity, special interface, high viscosity of the components, and laminating trend of the original pellet of the dispersed phase . The four sufficient conditions are the shear field of low shear rate, proper stabilizing condition, bi-axial orientation of the melted dispersed phase and the type of the lamellar flow. Besides, is was suggested that two fundamental factors which limit the formation of lamellar morphology in a multiphase polymer are the viscosity rate of the two phases and the interface condition, which are the internal factors to determine the deforming ability of the...
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