Heat conductive h‐BN/CTPB/epoxy with enhanced dielectric properties for potential high‐voltage applications

Abstract

To enhance the toughness and electrical insulation properties of cured epoxy, carboxyl-terminated polybutadiene (CTPB) liquid rubber was used to modify epoxy in this study, and the thermal conductivity, mechanical and dielectric properties of modified epoxy were investigated. The results indicate that the CTPB-epoxy exhibits higher impact strength and lower dielectric constant and loss compared with pure epoxy. Further, hexagonal boron nitride (hBN) was used to reinforce epoxy modified with 20 phr CTPB. It is found that compared with the hBN/epoxy under the same filler loading, the heat conductive hBN/CTPB/epoxy possesses a lower dielectric permittivity and dissipation factor in all frequency ranging from 10 2-10 7 Hz, a higher electrical resistivity and dielectric breakdown strength, and improved mechanical toughness. Therefore, the prepared hBN/CTPB/epoxy composites are potentially useful in practical electrical insulation applications.

Surface modification of a BN/ETDS composite with aniline trimer for high thermal conductivity and excellent mechanical properties

“…22,23 We assume that the increased surface wettability between the ETDS matrix and the BN ller improves the thermal conductivity of the AT surfacetreated BN composite, which reduces voids and provides bridges for heat conduction. 24,25 However, the thermal conductivities of the composites did not increase at higher AT weight ratios. The BN/ETDS composite with the highest thermal conductivity is AT-BN_2, followed by AT-BN_3 and AT-BN_1.…”

Dielectric Relaxation Characteristics of Epoxy Resin Modified with Hydroxyl-Terminated Nitrile Rubber

“…Liquid rubber, such as hydroxyl-terminated liquid nitrile rubber (HTBN), is one kind of efficient toughener for epoxy resin owing to the simple operation process [ 1 , 2 ]. Epoxy resin/liquid rubber composites and their nano modified composites have been applied to electrical packaging and power equipment, so the dielectric properties must be of comparable concern [ 3 , 4 ]. Liquid rubber uniformly disperses in the matrix in the form of discrete phases, and the dielectric properties are changed, which is attributed to the variation of relaxation behaviours [ 5 , 6 ].…”

“…Zhou and his co-workers modified epoxy resin with hydroxyl-terminated polybutadiene (HTPB) liquid rubber [ 11 ], and the interfacial polarization is mentioned, but its relaxation characteristics are excluded. The influence of carboxyl-terminated polybutadiene liquid rubber (CTPB) has also been studied [ 4 ]. The ternary h-BN/CTPB/epoxy shows better dielectric and thermal properties, but only the dielectric properties at room temperature are analysed.…”

Core‐shell structured Al/PVDF nanocomposites with high dielectric permittivity but low loss and enhanced thermal conductivity

“…At low frequency, it decreases with the increase of temperature; at high frequency, it decreases at first and then becomes stable with increasing temperature. A depression of the modulus with temperature at high frequency is observed, which could be attribute to the conduction mechanism that is due to the short range mobility of charge carriers . From Fig.…”