Long-term performance of β-nucleated toughened polypropylene-biocarbon composites

Thermoplastic polyolefins or TPOs are of widespread use in the automotive industry. In this study, the long-term performance of biocarbon based TPOs is investigated for the first time. The durability of these bio-based composites with and without hindered phenolic antioxidants was investigated under accelerated heat aging for 1000 h. Thermo-oxidative degradation was tracked along the specimen's thickness using energy dispersive spectroscopy. Performance of the biocomposites was gauged by Izod notched impact and tensile properties. Microstructural changes were monitored by differential scanning calorimetry and dynamic mechanical analysis. While the tensile properties were sufficiently sustained using the antioxidants after this test, the impact strength failed to retain initial values. The morphological changes in the β crystal phase were recognized as the primary factor in the reduction of the impact strength of the biocomposites.