Abstract: Thermal insulative composites were prepared with PA6 as a matrix and BN as thermal conductive filler through a twinscrew extruder. The effect of BN content and particle size on the insulation property was studied. For various particle size, the thermal conductivity of the composites increased with increasing content of the filler. When the particle size of BN was 5 μm, filling content was 25 vol %, the thermal conductivity reached 1.2187 W/(m·K). For improving the thermal conductivity, flaky BN filler was more effective than spherical filler, and bimodal particles were more effective than monomodal ones. Using a binary filler mixture at a content of 20 vol % in which the size of the two fillers were 5 and 150 μm, and the volume ratio was 1:3, the thermal conductivity reached 1.3573 W/(m·K).

Key words: polyamide 6, boron nitride, composite, thermal conductivity, insulation