Original paper(Vol.47 No.12 pp.1281)

Structure and mechanical properties of injection molded thin strip of carbon fiber reinforced liquid crystalline polymer

Baba Fumiaki; Fujita Akihiro; Hamada Hiroyuki

Abstract:Liquid crystalline polymer (LCP) shows a unique structure and mechanical properties of injection molded thin strips. In this study, three kinds of thin strip, 5mm width and 0.mm, 0.5mm and 1.0mm thickness were made by injection molding. The effects of injection speed and thickness of mold cavity on the structure and mechanical properties of carbon fiber reinforced LCP injection molds were investigated.
Both the storage modulus and tan delta of the specimens with the thinnest thickness had the highest value. The storage modulus in both tensile and flexural modes decreased with increasing of the thickness in each specimen. Multilayer structure were observed in all specimens. The number of layers were different by the thickness and the injection speed of specimen. The fiber orientation of each layer also changed by the thickness and the injection speed of specimen.

Key Words:liquid crystalline polymer, injection molding, mechanical property, carbon fiber, multi layer structure