Methods and apparatuses for making nanomaterials are disclosed. The methods involve passing one or more source materials through a high pressure and high temperature chamber with an open throat, and then allowing the reactants to expand into a lower pressure, lower temperature zone. The source material is non-stoichiometric and fuel-rich so that excess un-combusted primary source material can form the nanomaterials. In some cases, the apparatus may be in the form of a modified rocket engine. The methods may be used to make various materials including: carbon nanotubes, boron nitride nanomaterials, titanium dioxide, and any materials that are currently produced by flame synthesis, including but not limited to electrocatalysts. The methods may also be used to make nanomaterials outside the Earth's atmosphere. The methods can include making, coating, or repairing structures in space, such as antennae.

A process for producing a material in the form of nanosheets by ball milling of crystals of the material, wherein the ball milling takes place in the presence of a reactive gas.

A method and apparatus for preparing boron nitride nanotubes (BNNTs) according to an embodiment may ensure mass-production, may increase yield by reducing a production time, and may prepare BNNTs with high purity.

Disclosed herein are processes for purifying as-synthesized boron nitride nanotube (BNNT) material to remove impurities of boron, amorphous boron nitride (a-BN), hexagonal boron nitride (h-BN) nanocages, h-BN nanosheets, and carbon-containing compounds. The processes include heating the BNNT materials at different temperatures in the presence of inert gas and a hydrogen feedstock or in the presence of oxygen.

Described herein are apparatus, systems, and methods for the continuous production of BNNT fibers, BNNT strands and BNNT initial yarns having few defects and good alignment. BNNTs may be formed by thermally exciting a boron feedstock in a chamber in the presence of pressurized nitrogen. BNNTs are encouraged to self-assemble into aligned BNNT fibers in a growth zone, and form BNNT strands and BNNT initial yarns, through various combinations of nitrogen gas flow direction and velocities, heat source distribution, temperature gradients, and chamber geometries.

A method and apparatus for preparing boron nitride nanotubes (BNNTs) according to an embodiment may ensure mass-production, may increase yield by reducing a production time, and may prepare BNNTs with high purity.

Disclosed herein is a method for preparing amine-boranes.

A process for obtaining borazane (NH.sub.3—BH.sub.3) includes introducing anhydrous liquid ammonia (NH.sub.3(l)) into a reactor thermostatically regulated to between a temperature θ.sub.1 and 40° C.; introducing, with stirring, into the reactor an amine borane complex (Am.BH.sub.3), the corresponding amine (Am) of which is soluble in anhydrous liquid ammonia only to a proportion of less than 10 g in 100 g of ammonia at 20° C., being introduced in an amount such that the mole ratio R=(NH.sub.3(l))/(Am.BH.sub.3) is greater than or equal to 5; stirring the mixture; stopping the stirring to obtain two demixed phases: a light phase constituted essentially of a solution of anhydrous liquid ammonia (NH.sub.3(l)) containing borazane; and a heavy phase constituted essentially of the amine corresponding to the amine borane complex introduced; isolating the borazane and drying under vacuum thereof; the temperature θ.sub.1 being greater than or equal to the melting point of the amine borane complex.

This disclosure relates to porous boron nitride and a method for preparing the same. The porous boron nitride of the present invention may be obtained by mixing a boron source with a nitrogen source, heating the mixture to form a compound, and then, extracting elements other than boron and nitrogen. The porous boron nitride of the present invention comprises both micropores and mesopoers, and it has a large specific surface area, and thus, may be usefully used in various fields.

To provide a composition for a three-dimensional integrated circuit capable of forming a filling interlayer excellent in thermal conductivity also in a thickness direction, using agglomerated boron nitride particles excellent in the isotropy of thermal conductivity, disintegration resistance and kneading property with a resin. A composition for a three-dimensional integrated circuit, comprising agglomerated boron nitride particles which have a specific surface area of at least 10 m.sup.2/g, the surface of which is constituted by boron nitride primary particles having an average particle size of at least 0.05 μm and at most 1 μm, and which are spherical, and a resin (A) having a melt viscosity at 120° C. of at most 100 Pa.Math.s.