Achieving High Thermal Conductivity in Epoxy Composites: Effect of Boron Nitride Particle Size and Matrix-Filler Interface

For the thermal management of high watt density circuit layers, it is common to use a filled epoxy system to provide an electrically insulating but thermally conducting bond to a metal substrate. An epoxy-thiol system filled with boron nitride (BN), in the form of 2, 30 and 180 µm platelets, has been investigated with a view to achieving enhanced thermal conductivity. The effect of BN content on the cure reaction kinetics has been studied by differential scanning calorimetry and the thermal conductivity of the cured samples has been measured by the Transient Hot Bridge method. The heat of reaction and the glass transition temperature of the fully cured samples are both independent of the BN content, but the cure reaction kinetics is systematically affected by both BN content and particle size. These results can be correlated with the thermal conductivity of the cured systems, which is found to increase with both BN content and particle size. For a given BN content, the thermal conductivity found here is significantly higher than most others reported in the literature; this effect is attributed to a Lewis acid-base interaction between filler and matrix.

The effect of modified AlN on the thermal conductivity, mechanical and thermal properties of AlN/polystyrene composites

Modified aluminum nitride particle/polystyrene (AlN/PS) composite was prepared by a powder processing technique.

A Multilayer Coating Method to Prepare Borosilicate Glass-Aluminum Composite Coating on Cubic Boron Nitride Particle

CBN particles coated with borosilicate glass-aluminum composite coating (Glass-Al-CBN) were prepared by a multilayer coating method. The coated composite particles were sintered at 800°C for 2h. XRD, DTA-TG, SEM techniques were used to characterize the samples. It was found that AlN was formed by the reaction of Al and CBN. The mechanical properties and the oxidation resistance of the composite was improved due to the presence of the glass coating and alumina.