Highly Ordered BN⊥–BN⊥ Stacking Structure for Improved Thermally Conductive Polymer Composites

Ghosh, Barun; Xu, Fang; Grant, David M.; Giangrande, Paolo; Gerada, Chris; George, Michael W.; Hou, Xianghui

Abstract

The substantial heat generation in modern electronic devices is one of the major issues requiring efficient thermal management. This work demonstrates a novel concept for the design of thermally conducting networks inside a polymer matrix for the development of highly thermally conductive composites. Highly ordered hexagonal boron nitride (hBN) structures are obtained utilizing a freeze‐casting method. These structures are then thermally sintered to get a continuous network of BN⊥–BN⊥ of high thermal conductivity in which a polymer matrix can be impregnated, enabling a directional and thermally conducting composite. The highest achieved thermal conductivity (K) is 4.38 W m−1 K−1 with a BN loading of 32 vol%. The effect of sintering temperatures on the K of the composite is investigated to optimize connectivity and thermal pathways while maintaining an open structure (porosity ≈ 2.7%). The composites also maintain good electrical insulation (volume resistivity ≈ 1014 Ω cm). This new approach of thermally sintering BN⊥–BN⊥ aligned structures opens up a new avenue for the design and preparation of filler alignment in polymer‐based composites for improving the thermal conductivity while maintaining high electrical resistance, which is a topic of interest in electronic packaging and power electronics applications.

Citation

Ghosh, B., Xu, F., Grant, D. M., Giangrande, P., Gerada, C., George, M. W., & Hou, X. (2020). Highly Ordered BN⊥–BN⊥ Stacking Structure for Improved Thermally Conductive Polymer Composites. Advanced Electronic Materials, 6(11), Article 2000627. https://doi.org/10.1002/aelm.202000627

• Journal Article Type: Article
• Acceptance Date: Sep 16, 2020
• Online Publication Date: Oct 8, 2020
• Publication Date: 2020-11
• Deposit Date: Dec 2, 2020
• Publicly Available Date: Dec 8, 2020
• Journal: Advanced Electronic Materials
• Electronic ISSN: 2199-160X
• Publisher: Wiley
• Peer Reviewed: Peer Reviewed
• Volume: 6
• Issue: 11
• Article Number: 2000627
• DOI: https://doi.org/10.1002/aelm.202000627
• Keywords: Electronic, Optical and Magnetic Materials
• Public URL: https://nottingham-repository.worktribe.com/output/4948508
• Publisher URL: https://onlinelibrary.wiley.com/doi/10.1002/aelm.202000627