Global evolution towards the electric vehicles (EVs) has increased the usage demand for lightweight, cost effective and sustainable materials, to improve the energy efficiency and extend driving range. Recycled polymers offer a reduced carbon footprint, while retaining the mechanical strength of non-structural EV battery housings, to support the circular economic goals in the automotive sector. In this work, the thermoplastic material is compounded by melt mixing recycled polypropylene (rPP) with glass fiber (GF) and varying proportion of surface modified Aluminum nitride (mAlN) as thermal fillers to overpower the low thermal conductivity of rPP. Similarly, GF reinforcement is used to improve its stiffness and mechanical stability lost during the recycling process. The mechanical characterization study is carried out on the prepared composite material as per ASTM standards. The addition of GF has enhanced the stiffness and strength of rPP without significantly reducing its ductility. The thermal conductivity of the composite is observed to gradually increase with the filler concentration. It is important to note that the composites with increased percentages of mAlN possessed thermal conductivity of 2.132 W/mK. Also, the TGA analysis proved that addition of mAlN slowed the thermal degradation process, enhancing its thermal stability at high temperatures. The results reveal that the hybrid reinforcement of rPP with mAlN and GF helps in effectively balancing the mechanical and thermal behavior. In addition to the performance improvement, the usage of rPP also helps in reducing the waste and facilitating sustainability.
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