Improvement of fiber dispersion and mechanical property of long fiber reinforced thermoplastics prepared by pultrusion-impregnation

Abstract

Long fiber reinforced Thermoplastics (LFT) is a material technology that can greatly improve strength and durability of thermoplastic resin. In particular, LFT pellets are applicable to automotive and mass-production industry because they can be easily molded through injection molding. Currently, commercialized LFTs are polypropylene pellets reinforced with glass fibers, because they are the most economical, lightweight and easy to process materials. However, in the injection molded LFT, improvement of the problem of the physical property deviation due to the difference of fiber dispersion and the fiber length is required. In this study, LFT pellets reinforced with glass and carbon fiber prepared by using continuous fiber impregnation technique to improve the mechanical strength and fiber dispersion quality in final injection product. First, we studied the impregnation die technology that can improve fiber dispersion, and then optimization of the mechanical properties in the injection molded LFT was studied by analyzing the property changes of LFT according to the final fiber length after injection molding.