Nanostructure-reinforced composite articles and methods
The present invention provides methods for uniform growth of nanostructures such as nanotubes (e.g., carbon nanotubes) on the surface of a substrate, wherein the long axes of the nanostructures may be substantially aligned. The nanostructures may be further processed for use in various applications, such as composite materials. For example, a set of aligned nanostructures may be formed and transferred, either in bulk or to another surface, to another material to enhance the properties of the material. In some cases, the nanostructures may enhance the mechanical properties of a material, for example, providing mechanical reinforcement at an interface between two materials or plies. In some cases, the nanostructures may enhance thermal and/or electronic properties of a material. The present invention also provides systems and methods for growth of nanostructures, including batch processes and continuous processes.
1. A method of forming a composite article, comprising:
providing a first and a second substrate, each having a joining surface;
arranging a set of nanostructures on or in the joining surface of at least one of the first and second substrates, wherein long axes of the nanostructures are substantially aligned and non-parallel to the joining surfaces of the first and second substrates, and nanostructures within the set are in contact with each other; and
binding the first and second substrates to each other via their respective joining surfaces to form an interface of the substrates, wherein the interface comprises the set of substantially aligned nanostructures,
wherein:
during the binding, capillary action causes polymer from the first substrate to penetrate into the set of substantially aligned nanostructures such that polymer from the first substrate contacts material from the second substrate, and
during and after the binding, the alignment of the nanostructures is substantially maintained.
2. The method of claim 1 , wherein the nanostructures comprise nanotubes, nanofibers, and/or nanowires.
3. The method of claim 1 , wherein the nanostructures comprise nanotubes.
4. The method of claim 1 , wherein the nanostructures comprise carbon nanotubes.
5. The method of claim 1 , wherein the long axes of the nanostructures are substantially aligned and perpendicular to the joining surfaces of the first and second substrates.
6. The method of claim 1 , wherein the nanostructures are arranged in a forest.
7. The method of claim 1 , wherein the first substrate comprises epoxy polymer.
8. The method of claim 1 , wherein, during the binding, capillary action causes polymer from the second substrate to penetrate into the set of substantially aligned nanostructures.
9. The method of claim 8 , wherein the second substrate comprises epoxy polymer.
10. The method of claim 1 , wherein, while arranging the set of substantially aligned nanostructures on or in the joining surface, the nanostructures are not associated with a support material.
11. The method of claim 1 , wherein the first substrate is a prepreg.
12. The method of claim 11 , wherein the second substrate is a prepreg.
13. The method of claim 1 , wherein the nanostructures penetrate the joining surface of the second substrate.
14. The method of claim 1 , wherein at least one of the first and second substrates comprises a catalyst material.
15. The method of claim 14 , wherein the arranging comprises catalytically forming nanostructures on the surface of at least one of the first and second substrates.
16. The method of claim 1 , wherein the nanostructures have diameters of 100 nm or less.
17. The method of claim 1 , wherein the nanostructures have aspect ratios of greater than 100.