EFFECTS OF MOLDING PROCESS ON RESIDUAL FIBER LENGTH OF LONG FIBER POLYPROPYLENE COMPOSITES

摘要

Fiber length distributions were determined for long fiber polypropylene composites reinforced with carbon, glass or glass-organic fibers from pultruded pellets, chopped fiber, or in-line roving, and molded by multiple long fiber thermoplastic injection (LFT-IM) or extrusion-compression molding (LFT-ECM) processes. All processes degraded the fiber length significantly. Injection molding processes reduced fiber length by up to 90%, much more than LFT-ECM, which produced broad, asymmetrical residual length distributions, with substantial amounts of much longer fibers.