Thermography for polymers film blowing

Abstract

Polymer temperature distribution in film blowing was investigated by means of an IR thermography system sensing in the window between 2 and 5Jlm. Since in this band polymers behave as selective emitters, the emission and reflection of the radiation are bulk and surface phenomena. Thus, a preliminary study on the film radiative behaviour is presented in order to characterise the thermography readout on semitransparent sheets. Then, experiments on film blowing extrusions have been performed with polypropylene on a pilot plant in order to measure the on-line film temperature distribution for different working conditions.