A Review of Processing Methods and Modification of Reinforcements Used in Polypropylene Composites

The fabrication of polypropylene composites using various types of reinforcements to improve the mechanical properties has received much attention in recent years. In this paper, enhancing the mechanical properties of polypropylene composites by adding different classes of natural and synthetic particle and fiber reinforcements were reviewed. Accordingly, it was found that the fabrication of polypropylene composites leads to an increase either in the strength of samples and corresponding mechanical properties. Moreover, surface modification and processing reinforcements, especially natural fibers via chemical and physical methods were studied. The results show an increase in the adhesion of reinforcements surface inside the polypropylene, which results in strength enhancement and improving the mechanical properties of polypropylene composites. The evidence from this study points towards the idea that the increased use of modified natural fibers in polylropylene composites and those natural or synthetic reinforcements which form hybrid composites provide promising research topics in the future.