A gradient structure formed in injection‐molded polycarbonate in situ hybrid composites and its corresponding performances

Abstract

Three polycarbonate (PC) composites that were reinforced, respectively, with liquid crystalline polymer (LCP), glass fibers, and both of them were prepared by a single injection-molding process. The role of LCP in improving the processibility of the composites was characterized by torque measurement test. The transitions of LCP morphology in two-and three-component composites were investigated by using polarizing optical microscopy and scanning electron microscopy. The micrographs showed a skin-core gradient structure in all three systems investigated, and the addition of glass fiber to the PC/LCP blend affected the morphological transition and content distribution of dispersed LCP phase through the thickness of the injection-molded samples. These results were correlated well with the measurements of tensile mechanical properties and dynamic mechanical analysis. How to fully use the dispersed LCP phase in PC in situ hybrid composites was discussed for the thickness change of core layer and the heterogeneous distribution of more LCP in the core. © 2004 Wiley Periodicals, Inc. J Appl Polym Sci 94: [625][626][627][628][629][630][631][632][633][634] 2004

Phase Diagram for Predicting In Situ Fibrillation of LCP During Molding

“…The remaining solution containing the LCP residue was then centrifuged so that the residue could be collected and dried [19,20]. The residues were then coated with gold and prepared for observation under the scanning electron microscope (SEM).…”

Polycarbonate composites: Effect of filler type and melt‐blending process on the light diffusion properties

“…Therefore, it is very important to obtain effective dispersion of such a small amount of LDAs in the polymer composites. Melt‐mixing, in situ blending and solution processing are commonly used methods to prepare LDMs . It is widely accepted that melt‐blending is the most convenient and preferred method for industrial applications because it is a simple, low cost, and environmentally friendly technique .…”