ランダム配向繊維強化熱可塑性樹脂系複合材料の一製造法と力学的性質
A Method for the Production of Randomly Oriented Fiber Reinforced Thermoplastic Composites and Their Mechanical Properties
北野 武・長塚惟宏・李 明雄・君島謙二・大柳 康
Kitano, Takeshi / Nagatsuka, Yoshihiro / Lee, Myoung Woong / Kimijima, Kenji / Oyanagi, Yasushi
A unique method for the production of well mixed reinforced fiber/thermoplastic fiber mats for compression molding or stampable sheet molding was developed. In this method, bundles of continuous or discontinuous fibers are supplied to the apparatus, which is called "fiber separating/flying machine", and the fibers are mixed homogeneously after separation and cutting of the fiber bundles. Various reinforcement mixed mats using carbon fiber (CF), glass fiber (GF), aramid fiber (KF) and thermoplastic matrix polyamide fiber (PA6) were prepared by this method. Operating conditions of the machine for the preparation of the uniformly mixed mats, their properties and also compression molding conditions were investigated. Various mechanical properties of these composites were measured, and the influence of content of reinforcement fibers, their properties and orientation on the mechanical properties were discussed. The tensile properties of CF reinforced PA6 composites did not increase monotonically with increasing fiber content, but rather decreased when filler content exceeded 20%, which seems to be due to a change in the fiber orientation. KF reinforced PA6 composites showed the highest impact strength and fracture toughness of the materials investigated in this study, and it was found that KF is able to improve the fracture properties of CF and GF reinforced composites.
Key words: Fiber reinforced thermoplastic composites / Compression molding / Reinforcement fiber / Thermoplastic fiber mixed mat / Mechanical properties