A hybrid green composite for automotive industry

Hybrid composites were prepared using recycled polypropylene (rPP), dimension stone waste (Bege Bahia, BB) and coconut fiber (CF). Post-consumer the formulations of rPP/BB/CF and virgin PP, were processed in a Haake mixer. The films were characterized according to chemical, physical and mechanical properties. Multiple linear regression tests were used to develop mathematical models, which allow simulating the behavior of the composition of composite on mechanical properties. Density variations were associated with differences in particle packing and particle wall roughness. The impact resistance of rPP/BB/CF was slightly higher in the 70/10/20 wt% composite. SEM micrographs of the ternary (70/20/10 wt%) showed stronger traces of decohesion, allowing higher water absorption and reducing impact resistance. The response surface methodology suggest that the increase in the variable “coconut fiber content” is responsible for improving the mechanical properties of the composite. The ternary composite (70/10/20 wt%) was best for replacement of virgin PP.