Molecular orientation of extruded PET/LCP blend films. II. X‐ray pole figures

Abstract

AbstractThe crystalline uniaxial molecular orientation of two liquid crystalline polymers (LCPs), Vectra®A950, and Rodrun®LC5000, blended with poly(ethylene terephthalate) (PET) was obtained from wide angle X‐ray pole figures. The blends films were produced by extrusion using a twin screw extruder with a slit die. The molecular orientation was evaluated along the transverse section of the films and as a function of the blends composition. The influence of a compatibilizer agent on the LCPs orientation was also analyzed. It was found that the orientation of both LCPs in the pure LCP films was high, highest in the draw direction but variable along the transverse section of the extruded films; in this last case, it was higher at the position where the shear rate was maximum. However, a drastic orientation decrease in both LCP's phases was observed in the films made of PET/LCPs blends. The maximum orientation effects were observed for the blend with 5 wt % of LCP content and also at the position where the shear rate was the highest. The Vectra®A950 LCP, as a pure material and in the blend with PET, orient more effectively than the Rodrun®LC5000 LCP in the films produced at the same processing conditions. The results showed that the use of a compatibilizer agent decreased the LCP orientation and were in accordance with previous studies using polarized infrared spectroscopy. © 2007 Wiley Periodicals, Inc. J Appl Polym Sci, 2007