Glycine functionalized boron nitride nanosheets with improved dispersibility and enhanced interaction with matrix for thermal composites

Liquid Metal-Assisted High-Efficiency Exfoliation of Boron Nitride for Electrically Insulating Heat-Spreader Film

“…The classical ball-milling process for the fabrication of BNNSs and its mechanism, for example, using urea as the exfoliation agent, are shown in Figure S2. , The sizes and thicknesses of h-BN particles are reduced due to the synergistic effect of powerful shearing force and high-energy collisions. Simultaneously, the N atoms of amino groups can be covalently bonded with the B atoms, which are exposed at the edges or defects of BNNSs to prevent restacking of BNNSs.…”

“…In the ball-milling process, h-BN powders were subjected to a synergetic effect of mechanical shear force and chemical peeling to overcome the interaction between the neighboring h-BN layers; simultaneously, some additional agents such as molten hydroxides, sodium borohydride, sodium hydroxide, urea, l -glutamine, ammonium fluoride, and β-cyclodextrin serve to functionalize the BNNSs to significantly improve the dispersion stability in the solvent. To date, the BNNSs yielded by the ball-milling strategy are reported to be as high as ≥40%. ,,− However, most exfoliation studies ignore the complexity of postprocessing after the ball-milling process, like the fact that hydro-soluble ball-milling reagents often require repeated centrifugation and washing, which wastes a lot of time and water; most ball-milling procedures require an excessively long ball-milling time to achieve a high exfoliation yield, consuming a significant amount of energy and scarifying the exfoliation efficiency. Therefore, a more efficient ball-milling strategy with facile post-treatment and high yield in a short time to prepare BNNSs is urgently needed.…”

Highly flexible cellulose nanofiber/single-crystal nanodiamond flake heat spreader films for heat dissipation

“…[22][23][24] The intrinsic thermal conductivity of hexagonal boron nitride (h-BN) and Al 2 O 3 are insufficient, while the application of boron nitride nanosheets (BNNSs) with their high thermal conductivity is problematic because of their high cost and resultant agglomeration. [25][26][27] Additionally, preparing composite films with high thermal conductivity requires the addition of high-loading BNNS, which leads to films with poor flexibility. 28 Nanodiamond (ND) is a hydrophilic nanocarbon diamond possessing high thermal conductivity (À2000 W m À1 K À1 ) and excellent electrical insulation (10 7 V cm À1 ) at room temperature, offering great potential applications in the field of thermal management of electrical systems.…”

“…22–24 The intrinsic thermal conductivity of hexagonal boron nitride (h-BN) and Al 2 O 3 are insufficient, while the application of boron nitride nanosheets (BNNSs) with their high thermal conductivity is problematic because of their high cost and resultant agglomeration. 25–27 Additionally, preparing composite films with high thermal conductivity requires the addition of high-loading BNNS, which leads to films with poor flexibility. 28…”

Exfoliation of hexagonal boron nitride assisted with hierarchical ionic fragments by ball‐milling for achieving high thermally conductive polymer nanocomposite

“…Other volatile organic liquid solvents assisted ball milling may lead to environmental risks. On the contrary, solid agents assisted ball milling are versatile, such as benzyl benzoate, [10] urea, [11] phosphonated polyethyleneimine, [12] sugar, [13] the mixture of ammonium phosphate and sodium hydroxide powder, [14] glycine, and [15] boric acid. [16] Accordingly, agents for the ball milling h-BN exfoliation cannot only weaken the milling force to protect the integrity of BNNSs but also realize purposive functionalization.…”