Reduced fiber breakage in an injection molding machine
Abstract
An experimental investigation of the flow behavior of a glass fiber reinforced polypropylene in an injection molding machine revealed that it was possible to reduce the extent of fiber breakage occurring through the addition of a blowing agent. With the increased addition of a chemical blowing agent, from 0 to 5 wt%, the fibre length distribution was found to increasingly resemble the virgin resin. Rheological study of this phenomenon with an in-line rheometer showed that the blowing agent changed the pseudoplasticity of the composite. As a result of the change in pseudoplasticity, less glass fibers were exposed to shear flow and therefore did not experience rotation normally leading to fibre breakage.