Extrudate Swell Behavior of Glass Fiber Filled Polyamide 6

This paper discusses the extrudate swell behavior of glass-filled polyamide 6. The key features of the experiments were the facility to extrude directly into a density matched oil kept at extrusion temperature and thus, the ability to measure the diameter of the extrudate of the glass-filled polyamide immediately upon exit from the die, without the extrudate contacting air and as a function of time in a chamber under isothermal and neutrally-buoyant conditions. The concentration and orientation of the fibers of the extrudates were also studied using X-ray radiography in a post-mortem fashion. A skin/core morphology, where uniaxially aligned fibers constitute the skin zone and the core contains a reduced concentration of fibers, was observed.