Synergistic Effects of Aluminum Nitride and Super Thermal Conductive Graphite in Polypropylene‐Based Hybrid Composites: Structural, Mechanical, and Thermal Insights

In this study, hybrid polymer composites based on polypropylene (PP) are developed using aluminum nitride (AlN) and super thermal conductive graphite (Gr) as fillers to improve mechanical, structural, thermal, and electrical properties. A series of composites containing varying ratios of AlN and Gr are fabricated via melt mixing and hot‐press molding techniques. The synergistic effects of ceramic and carbon‐based fillers are systematically investigated through mechanical testing, SEM analysis, DSC/TGA thermal characterization, and electrical resistivity measurements. Results show that low filler concentrations led to improved dispersion, mechanical integrity, and enhanced thermal properties. The Gr addition act as an efficient nucleating agent and significantly increases crystallinity and thermal conductivity, while AlN contributes to mechanical reinforcement. In comparison with neat PP, the 10A20G composite exhibits ≈63% (≈1.6‐fold) higher thermal conductivity and about 10 ⁴ times lower electrical resistivity, confirming its suitability for thermal interface applications. The findings suggest that the hybrid use of AlN and Gr can lead to high‐performance PP‐based composites for electronic packaging and thermal management applications.