Boron Nitride Nanotubes (BNNT)

The nanomaterial for aggresive enviroments.

Inert and oxidatively stable

BNNTs possess thermal stability from 900 °C [1] to well over 1000°C [2,3], as compared to only 400-600 °C for carbon nanotubes. This allows the use of BNNTs as reinforcement for ceramic and metal matrices, where high processing temperatures would prevent the use of CNTs. The chemistry of BNNTs also enables their use in metal matrices, where CNTs cannot be used for reactivity reasons.

A high-strength reinforcement material

The elastic modulus of BNNTs is identical to that of carbon nanotubes, with reported values of 1.22-1.3 TPa. [4, 5] The tensile strength of individual BNNTs has been reported at 33 GPa [6], and single-walled BNNTs show buckling characteristics superior to single-walled carbon nanotubes. All of this indicates that BNNTs are a promising reinforcement material for ceramic, metal, and polymer matrices.

Favorable thermal and electrical properties

BNNTs are an electrical insulator [7-9], but possess extremely high thermal conductivity, predicted at 3000 W/m K for 14 nm tube diameters. This atypical combination of properties suggests that BNNT-reinforced materials may be useful in thermal management.

Light-weight radiation shielding

Boron nitride nanotubes represent a light-weight structural solution for radiation shielding, due to the very high neutron capture cross-section of 10B. 10B-enriched BNNTs are currently in development. BNNT-reinforced polymers are an attractive light-weight option for radiation shielding in aerospace applications.

Reduced chirality

The nature of the B-N bonds reduce the number of chiral variants available in BNNTs to zigzag and armchair.

Suggested applications

Aluminium alloy reinforcement for high-strength low-weight structures. Ceramic composites for hot-section turbomachinery. Glass fiber reinforcement for use in aggressive environments where high-strength and thermal resistance are required. Radiation shielding.

Material Properties

Appearance: Off-white to light-gray powder.
Chemical composition: 98.5 wt.% B and N. 80%+ boron nitride
nanotubes. Non-tubular BN mainly as sub-micron hexagonal boron nitride
Diameter: 10-200 nm
Wall-thickness: 2-10 nm
Maximum Length: ~500 μm
Average Length: 5μm
Oxygen: about 0.3 wt.% as B2O3
Metal catalysts: 0.05-0.1 wt.%
Bulk density: 0.2-0.5g/cm3

For details or more information, please contact us.