Polymer Film Blowing: Modeling☆

In polymer film blowing a tubular molten polymer film is extruded through an annular die and it is subsequently axially drawn and radially expanded. Bubble cooling is accomplished externally by tangentially impinging air jets and sometimes also internal cooling is used to increase the production rate. The thin membrane approximation is used in mathematical modeling of the molten polymer bubble. The aerodynamics of cooling play a significant role in bubble stability and final film quality.