Question

Rheology and importance in polymer processing

Answer 1

Polymer processing operations have typically been classified in one of two ways, by process or by the type of unit building blocks involved. Classifying operations by process is reminiscent of the unit processes concept found in the chemical engineering literature and in this approach we think of operations along the lines of specific polymers and whether the process is one of extrusion, injection molding, compression molding, blow molding and so on. Classifying operations according to the unit building blocks involved is, in some respects, similar to the unit operation concept and here we would cite as examples, pressurization and pumping of molten polymers, devolatilization, heat transfer, and polymer filtration. In either case, the analysis and design of polymer processes requires a knowledge and understanding of both the transport modes which are operative in a given process, and the rheological behavior of a given polymer under the conditions at which the process is being conducted.