Studies on Mechanical Properties of Discontinuous Glass Fiber/Continuous Glass Mat/Polypropylene Composite

The mechanical properties of discontinuous glass fiber/continuous glass fiber mat/polypropylene composites were investigated. The mechanical properties increased with increasing areal weight of the continuous glass mat, whereas the suitable content of discontinuous fiber was also depended on the mat areal weight. The impact strength of composites initially decreased due to the addition of discontinuous glass fiber, but increased when the content of discontinuous glass fiber further increased. Comparisons between the 4 mm discontinuous fiber length and the 12 mm fiber showed that the longer discontinuous glass fiber was advantageous to the mechanical properties of composite system. The modification of the interfacial adhesion between reinforcements and matrix resin by using functionalized polypropylene played a significant role in improving the mechanical properties of the composites. But the impact strength decreased above 5% of MA-g-PP level (with respect to matrix resin). It was also found that using a matrix resin with a high melt index was beneficial impregnation with the mechanical properties improving accordingly.