US 12,460,116 B2
BNNT thermal management material for high-power systems
Thomas G. Dushatinski, Newport News, VA (US); Thomas W. Henneberg, Newport News, VA (US); Clay F. Huff, Newport News, VA (US); Kevin C. Jordan, Newport News, VA (US); Jonathan C. Stevens, Williamsburg, VA (US); Michael W. Smith, Newport News, VA (US); R. Roy Whitney, Newport News, VA (US); Lyndsey R. Scammell, Newport News, VA (US); and Alex I. Wixtrom, Newport News, VA (US)
Assigned to BNNT, LLC, Newport News, VA (US)
Filed by BNNT, LLC, Newport News, VA (US)
Filed on Jun. 17, 2022, as Appl. No. 17/843,210.
Application 17/843,210 is a continuation of application No. 17/077,321, filed on Oct. 22, 2020, granted, now 11,390,787.
Application 17/077,321 is a continuation of application No. 16/512,857, filed on Jul. 16, 2019, granted, now 10,844,262, issued on Nov. 24, 2020.
Application 16/512,857 is a continuation of application No. PCT/US2019/018547, filed on Feb. 19, 2019.
Claims priority of provisional application 62/632,349, filed on Feb. 19, 2018.
Prior Publication US 2022/0325162 A1, Oct. 13, 2022
This patent is subject to a terminal disclaimer.
Int. Cl. C09K 5/14 (2006.01); C01B 21/064 (2006.01); H01L 23/373 (2006.01)
CPC C09K 5/14 (2013.01) [C01B 21/0648 (2013.01); H01L 23/3737 (2013.01)] 18 Claims
 
1. A thermal interface filler comprising:
50 to 90% by weight of a microfiller, a plurality of refined and deagglomerated boron nitride nanotubes (BNNTs) and a residual h-BN allotrope fraction, and
when the refined and deagglomerated boron nitride nanotubes (BNNTs) and a residual h-BN allotrope fraction are dispersed in a polymer matrix material, less than 1% of any remaining agglomerations in the refined and deagglomerated BNNTs have two dimensions that exceed 300 μm, wherein:
the BNNTs having a residual boron particle content of less than 10% by weight;
the percentage of remaining agglomerations is determined from a remaining agglomeration size distribution based on visual inspection of an optical microscope image at 10x magnification of the refined and deagglomerated BNNTs when dispersed in the polymer matrix material;
the residual h-BN allotrope fraction of the refined and deagglomerated BNNTs is less than 30% as determined through visual analysis of an HR-SEM micrograph at 20,000× magnification of the refined and deagglomerated BNNTs; and
the microfiller is selected from the group consisting of a diamond powder, alumina spheres, an electrically conductive filler, copper particles, silver particles, graphite particles, aluminum nitride, aluminum oxide, silicon nitride, nanofibrillated cellulose, and combinations thereof.