| Polymer alloys and blends are one of the most dynamic sectors of the polymer industry. The great majority of useful blends are immiscible, and in these blends, mechanical properties , to a great extent, are controlled by morphology, which in turn depends on the thermodynamic and rheological properties as well as deformation and thermal history.Modular intermeshing co-rotating twin screw extruders have many advantages over other mixers, such as modular design, better feeding and more positive conveying, self-wiping of the screw, short residence times, a narrow residence time distribution spectrum, better mixing, efficient devotalization. They are ideal mixers for polymer blending operations. Polymer alloys and blends are mainly produced using co-rotating twin screw extruders. The mixing that occurs in twin screw extruders greatly affects the final product performance. Consequently, it is important to be able to predict how blending conditions will influence the blend morphology.However, there is a dichotomy between science and technology in twin screw extruders. The theoretical analysis of a twin screw extruder operation remains undeveloped. The optimization of screw configuration for each application requires extensive experimental studies. Currently, selection of screw elements (screw configuration) and operating conditions in a co-rotating twin screw extruder is based on empirical studies, experience, and intuition.To reverse this situation, the present work studied the processing-rheology-morphology relationships in a modular intermeshing co-rotating twin screw extruder. A predictive model of morphology evolution during compounding of immiscible polymer blends was proposed. The influence of the screw configuration and operating conditions (e.g., screw rotating speed, output rate, and temperature profile) on blend morphology evolution was studied. The predictive model of morphology development in a twin screw...
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