Dietmar Rakutt

The influence of melt elongational properties on the morphology of PES cellular materials

Rheotens melt elongational experiments were performed to evaluate polyethersulfone with regard to its foamability. The effect of polymer molecular weight was correlated with the resulting foam cell morphology achieved under identical processing conditions in a batch process. It appears, that the melt strength of the polyethersulfone governs the average cell size, cell size distribution, as well as cell wall rupture during expansion and the corresponding compressive properties of the foam. These effects were further verified by a variation of the blowing agent content for polyethersulfone with a given molecular weight.