繊維複合液晶性高分子の射出成形における流動配向
Flow Induced Orientation in Injection Molding of Fiber/ Liquid Crystalline Polymer Composites
竹田 啓・堀口 智・小山清人
Takeda, Hiraku / Horiguchi, Satoshi / Koyama, Kiyohito
An experimental study of the morphology and orientation of injection molded LCP and fiber/LCP composites was carried out. The LCP studied was a completely aro-matic copolyester composed of 4-hydroxy-benzoic acid (HBA) and 2=hydroxy-6 naphtoic acid (HNA). The fibers were potassium titanate single crystal. The mor-phology and orientation of the samples were characterized by polarized optical micro scopy, scanning electron microscopy, scanning acoustic microscopy, and wide angle x-ray diffraction. Four layers wlth dlfferent morphologies were observed along the thickness direction in molded samples of LCP and fiber/LCP composites. The crystallinity of each layer increased with increasing distance from the surface molecular orientation of the three outher layers was parallel to the flow direction . The whlle that of the core layer was perpendicular to the flow direction. The fiber orientation of each layer was the same as the molecular orientation of the LCP. The fiber composites showed improved mechanical properties, such as bending modu-lus, strength, and interlaminar peel strength molded LCP plaques.
Key words: Injection molding / Liquid crystalline polymer / Layered structure / Fiber orientation / Rheology