INITIAL EXPANSION BEHAVIOR OF BUTANE-BLOWN LDPE FOAM AT EXTRUSION DIE EXIT

摘要

A CCD camera was used to observe n-butane-blown LDPE foams at the extrusion die exit. The effects of butane content, nucleating-agent (talc) content, aging modifier (GMS), die temperature, and geometry on the initial expansion behavior of the foam extrudate were studied. A transparent section of the foam extrudate was found at certain die temperatures. The reasons for the existence of this transparent section and its effect on the processing conditions and material formulations are discussed.