RU2458861C1 - Tubular or combined corundum nanofibre and method of its production - Google Patents

Abstract

FIELD: nanotechnology.

SUBSTANCE: invention relates to nanotechnology. Nanofibre is a tube made of corundum with nanothickness of walls or any fiber, covered with such tube. Corundum nanofibre is obtained by metallisation of any fiber with nanolayer of aluminium followed by oxidation of aluminium to the corundum and with the subsequent removal of the substance of the original fiber or without removing it.

EFFECT: obtained corundum nanofiber has superior strength and excellent thermal insulation properties.

7 cl

Description

Known methods for producing fiber from any substance by extruding it in the molten state through spinnerets, for example, fiberglass, see US Pat. USSR 291438. However, it is impossible to obtain a nanoscale fiber in this way.

Obtaining tubular fiber

Any fiber (as thin as possible) is covered with a layer of aluminum of a nano-thickness, and then aluminum is oxidized to corundum.

As the material of the initial fiber, materials that meet one of two qualities can be selected: either cheapness, for example, capron, viscose, or the ability to be drawn into as thin yarns as possible, for example F-1, F-2, F-3 fluoroplastics.

Coating the fiber with aluminum can be accomplished by vapor deposition of aluminum in a vacuum. Perhaps using electrostatics.

Oxidation of aluminum can be carried out either in an atmosphere of oxygen, ozone or a mixture thereof, or in a liquid medium, for example in a solution of hydrogen peroxide.

After the end of the oxidation of aluminum, the initial fiber can be removed from the formed corundum nanotube by gradually heating limited segments of the fiber / up to several meters, already in the form of fabric / in vacuum to the boiling point of the source fiber material. This material will gradually evaporate from the ends of the nanotube. The diameter of the resulting nanotube will be much larger than the nanoscale, but the nanosized material in this case is determined not by the diameter of the tube, but by the thickness of its walls. And this size can be arbitrarily small, right down to monomolecular.

The obtained tubular corundum nanofiber will have excellent strength / corundum is second only to diamond in strength, and in the nanostate it may surpass it / and very good thermal insulation properties both in vacuum and in the atmosphere.

It is also possible to remove the original fiber by accelerated heating. In this case, the tube will burst along, which will slightly affect its strength and thermal conductivity.

Or, the substance of the original fiber, if it does not interfere with the purpose of the corundum nanofiber, can remain in the tube. For example, if corundum nanofiber is designed to work for strength in composite materials, the original high-modulus high-strength fiber of the Zylon, Vectran-2000, Spectra, fiberglass, carbon fiber, Kevlar types will only increase the strength of the composite.

It should be noted that the original fiber can be in a plastic state, passed through rolls and have a flattened shape. A nanofiber of this shape will have increased flexural strength.

Claims (7)

1. A tubular or combined corundum nanofiber, which is a tube of corundum with a wall thickness or any fiber coated with such a tube. 2. The method of producing fiber according to claim 1, which consists in metallizing any fiber with an aluminum layer followed by oxidation of aluminum to corundum and subsequent removal of the substance of the original fiber or without its removal. 3. The method according to claim 2, characterized in that the initial fiber is kapron, or Kevlar, or Zylon, or Vectran, or spectrum, or viscose fiber, or carbon fiber. 4. The method according to claim 2, characterized in that the metallization occurs by the deposition of aluminum vapor in a vacuum. 5. The method according to claim 2, characterized in that the oxidation of aluminum is carried out in an atmosphere of oxygen, or ozone, or a mixture thereof, or in a solution of hydrogen peroxide. 6. The method according to claim 2, characterized in that the source fiber is removed by heating in vacuum. 7. The method according to claim 2, characterized in that the source fiber is previously passed through the rolls.