Short glass fiber-reinforced polyamide 6,6 composites toughened with maleated SEBS

Polyamide 6,6 hybrid composites toughened with maleated styrene-ethylene butylene-styrene (SEBS-g-MA) and reinforced with 5, 10, 15, 20 and 30% short glass fiber (SGF) were prepared by melt blending and subsequent injection molding. The matrix blend of composites consisting of 80 wt.% PA6,6 and 20 wt.% SEBS-g-MA. The mechanical behavior and fracture resistance of the SGF/ SEBS-g-MA/PA6,6 hybrid composites were investigated. Tensile test showed that the incorporation of SGF to the PA6,6/SEBS-g-MA 80/20 blend improves both the tensile strength and stiffness substantially at the expense of its tensile ductility. The essential work of fracture (EWF) methodology was used to evaluate the fracture toughness of the hybrids. EWF measurements indicated that the SGF additions are beneficial in enhancing the specific essential work of fracture (w_e) of the hybrids. The specific essential work of fracture appeared to increase with increasing fiber content up to 15%. It then decreased for the hybrids containing SGF content ≥ 20%. Overall, the w_e value of hybrids was higher than that of the unreinforced PA6,6/SEBS-g-MA 80/20 blend. The correlation between the microstructure and the fracture resistance of the hybrids is discussed.