摘要 |
A process for reducing polymer surging, lowering pressure and temperature fluctuations, and reducing polymer degradation while providing good overall throughput rate when plasticating and extruding low bulk density polycarbonate materials. The process involves a two-stage extrusion screw having a feed section with a constant channel depth of at least about 12 percent of the screw diameter and a transition section having a compression ratio of at least about 3:1. Thermoplastic low bulk density polycarbonate materials are extruded through a die in the shape of sheets, profiles, or films.
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