High‐performance hexagonal boron nitride/bismaleimide composites with high thermal conductivity, low coefficient of thermal expansion, and low dielectric loss

Abstract

High‐performance insulating materials have been increasingly demanded by many cutting‐edge fields. A new kind of high‐performance composites with high thermal conductivity, low coefficient of thermal expansion (CTE), and low dielectric loss was successfully developed, consisting of hexagonal boron nitride (hBN) and 2,2′‐diallylbisphenol A (DBA)‐modified 4,4′‐bismaleimidodiphenylmethane (BDM) resin. The effects of hBN and its content on the integrated properties, including curing behavior of uncured system, the CTE, thermal conductivity, dielectric properties, and thermal resistance of cured composites, are systematically investigated and discussed. Results show that there are amino groups on the surface of hBN, which supply desirable interfacial adhesion between hBN and BDM/DBA resin and a good dispersion of hBN in the resin. With the increase of the hBN content, the thermal conductivity increases linearly, whereas the CTE value decreases linearly; in addition, dielectric loss gradually decreases and becomes more stable over the whole frequency from 10 to 109 Hz. In the case of the composite with 35 wt% hBN, its thermal conductivity, CTE in glassy state, and dielectric loss are about 3.3, 0.63, and 0.5 times of the corresponding value of BDM/DBA resin, respectively. These attractive integrated properties suggest that hBN/BDM/DBA composites are high‐performance insulating materials, which show great potential in applications, especially for electronics and aerospace industries. Copyright © 2011 John Wiley & Sons, Ltd.

Preparation and characterization of thermally conductive thermoplastic polyurethane/h‐BN nanocomposites

“…High char yields were attributed to the presence of thermally stable h‐BN particles. Similar results were also obtained in h‐BN/bismaleimide composites . Moreover, experimentally obtained char yields are higher than the content of h‐BN.…”

“…Moreover, experimentally obtained char yields are higher than the content of h‐BN. This situation indicates a synergistic effect of h‐BN/TPU composites , and it can be related with the interaction between h‐BN and TPU matrix. To sum up, it can be said that the addition of nano h‐BN improved the thermal stability of TPU/h‐BN composites by contributing to the char formation.…”

“…Up to now several BN containing composites have been prepared and it was concluded that BN is the best material to obtain high thermal conductivity . For instance, Gao et al, prepared bismaleimide composites that contain micron‐sized hexagonal BN particles and found that the thermal conductivity of the composites increase linearly with the increase of the content of h‐BN . Yu et.…”

Polymer/boron nitride nanosheet composite with high thermal conductivity and sufficient dielectric strength

“…[14,15] Hexagonal boron nitride (BN) is structurally analogous to graphite and has equally good thermal transport properties. [16][17][18][19] Moreover, hexagonal BN in various forms (nanoplatelets, nanotubes, and nanosheets) is an attractive nanofiller material due to its low density (2.1 g/cm 3 ), high mechanical strength (Young's modulus: 0.7-0.9 TPa, yield strength:~35 GPa), good thermal conductivity (300 Wm À1 K À1 ) and chemical stabilities, and intrinsic electrical insulating properties. [20] Thus, BN has traditionally been considered as a material of choice in thermal-management applications.…”

Super stretchable hexagonal boron nitride Kirigami

“…With this set of unique features, BN nanomaterials show great potential as components of nanoelectronic devices [17], functional nanocomposites [18,19], hydrogen accumulators and other NEMS systems [20,21]. Considerable efforts have been made to explore the mechanical properties of h-BN both from a theoretical and experimental point of view [15,22,23].…”