繊維強化ポリプロピレンのウエルド隆起高さと衝撃強度に及ぼすガラス繊維の影響

Effect of Glass Fiber on Weld-line Protrusion Height and Impact Strength for FR-Polypropylene Composites

水谷治靖・小泉順二・奥本忠興

Mizutani, Haruyasu / Koizumi, Junji / Okumoto, Tadaoki

In the injection molded parts of glass fiber reinforced PP (PPG), the increase of fiber content to improve the mechanical properties, results in protruding the surface at weld-line region, where melt flows unite in at injection mold, and deteriorates the surface appearance.
In this study, the optimum material design were discussed to improve both surface appearance quality and mechanical property of PPG.
The weld-line protrusion height as the surface appearance quality and izod impact strength as the mechanical property were measured for PPG's with various fiber contents. The influences of fiber content, short-fiber/long-fiber ratio and flowability of matrix PP were discussed. It can be found that the low-flowability PP with a proper quantity of long fiber is effective for solving the weld-line protrusion without reducing the impact strength.

Key words: Fiber reinforced PP / Weld-line / Appearance quality / Glass fiber length

Seikei-Kakou, Vol.6, No.6, pp.426-433 (1994), Copyright (C) JSPP 1994-