PERPETUAL RECYCLING OF HYBRID-MOLDED AUTOMOTIVE COMPOSITES

In response to sustainability initiatives within the automotive sector, polymeric composites are gaining traction for their potential to achieve significant weight reduction without sacrificing properties. However, unlike their metal counterparts which almost retain virgin performance after reprocessing, fiber-reinforced composites encounter two primary challenges upon recycling: polymer degradation and fiber length attrition. To address these challenges and enable the perpetual recyclability of fiber-reinforced composites, a hybrid molding process has been developed. This approach combines a continuous unidirectional fiber preform (60 % GF PP) within a short fiber-reinforced polymer molding material (45 % GF PP) through injection molding. During recycling, virgin material is incorporated into the molding material to counteract polymer degradation, while chopping the continuous fiber preform supplements the diminishing fiber length distribution. Multiple configurations of the part were fabricated and their resulting properties were characterized across three rounds of recycling. This hybrid-molding process helps maintain the integrity of fiber-reinforced composites across multiple rounds of recycling, offering a viable pathway towards sustainable, high-performance composite materials in automotive part manufacturing.