Polypropylene Composite Materials with Natural Fiber Reinforcement: An Acoustic and Mechanical Analysis for Automotive Implementations

This research looks at the acoustic and mechanical characteristics of polypropylene (PP) composites supplemented with natural fibers to determine whether they are appropriate for automotive use. To generate composites that are hybrids, four diverse natural fibers, including Calotropis gigantea (CGF), jute, sisal, and kenaf, were mixed into PP matrices. The study examines how fiber type, frequency, and thickness affect sound absorption and mechanical strength. The results show that these natural fiber-reinforced composites have improved mechanical characteristics, with CGF (73.26 shore D value of Hardness), sisal (42.35 MPa tensile) and jute fibers showing particularly promising materials. Furthermore, the acoustic study emphasizes these materials’ frequency-dependent sound absorption properties, with particular efficacy in mid-frequency regions. Such organic reinforcement fiber materials’ acoustic performance is tested at 5 mm and 10 mm thicknesses. When a 5 mm thick sample is examined, it is clear that the coefficient of sound absorption is continuously less than 0.30 at 500 Hz and climbs to a range around 0.87 and 0.96 at 2000 Hz. Only Calotropis gigantea (CGF) and kenaf fibres show a steady rise in their sound absorption coefficient from 500 Hz to 2000 Hz as the sample thickness increases to 10 mm. This study contributes to developing environmentally friendly and superior materials for future automobile uses by providing helpful insights into the optimal configuration of naturally derived fiber-based composites for sound insulation and reinforcement of frameworks in the automobile industry.