Fecha de publicación: -- Fuente: Journal of applied polymer Lugar: RESEARCH ARTICLE Two processing schemes were developed for PP/POE/BN/SiCw composites to achieve random, dumbbell, and percolation structures. The two-step blending process produced a dumbbell structure superior to the random structure from one-step blending. Thermal conductivity depended strongly on filler content, and the percolation structure with 20 wt.% BN and 30 wt.% SiCw contributed to the thermal conductivity of 0.74 W·m−1·K−1.

ABSTRACT
Thermally conductive composites are regarded as effective solutions for thermal management in energy storage and electronic packaging. To investigate the structure and thermal conductivity of polyolefin composites, two processing schemes were developed to prepare the composites with polypropylene (PP), polyolefin elastomer (POE), boron nitride (BN), and silicon carbide whiskers (SiCw), and three models were built to simulate the heat transfer and the thermal conductivity by finite element analysis (FEA). The results revealed that the process schemes and the filler contents had profound effects on the structure and the thermal conductivity. By the two-step blending process, the composites with 20 wt.% BN and 20 wt.% SiCw showed the thermal conductivity of 0.59 W·m−1·K−1, illustrating the superiority of the dumbbell structure to the random structure by the one-step blending process. The evolved percolation structure with 20 wt.% BN and 30 wt.% SiCw contributed to the thermal conductivity of 0.74 W·m−1·K−1. The filler distribution can be modulated to construct a thermally conductive network by the processing schemes.