Processing issues of color mismatch: Rheological characterization of polycarbonate blends

Abstract

In this study, resins of two Lexan polycarbonates with and without the addition of pigments and additives were blended in a Thermo Haake Mini Lab II twin-screw micro compounder. The blends were rheologically characterized using dynamic strain sweep mode, dynamic frequency sweep mode, and steady rate sweep mode. The tests were performed at 230°C, 255°C, and 280°C under nitrogen atmosphere. The obtained results present that the variation in polycarbonate resin proportions and temperature significantly affected the rheological properties. The focus was extended on the polycarbonate blend having composition of two resins 30/70% and the obtained viscosity data was correlated to color changes. POLYM. ENG. SCI., 55:1994-2001, 2015.