Alfa fibers/clay hybrid composites based on polypropylene: Mechanical, thermal, and structural properties

In this work, two different natural fillers (alfa fibers and clay particles) were used to produce hybrid composites based on polypropylene. The samples were compounded by twin-screw extrusion and injection molding. As a first step, a constant overall filler loading was used (30 wt%) to study the effect of the relative filler loading. To improve adhesion with a matrix, alfa fibers were surface treated using an alkali solution, while the clay was purified and grinded to reduce particle sizes. The morphological, thermal, and mechanical properties (quasi-static and dynamic properties) were studied and found to vary with filler type and relative content. From the results obtained, it can be concluded that natural fiber-reinforced polymers combined with natural particulate fillers have advantages in terms of mechanical properties improvement, while increasing the use of natural materials. These hybrid composites show that new avenues are possible to reduce the use of synthetic fillers in composites.