High buoyancy composite materials

Patent metadata

Field	Value
Publication number	US-11561069-B2
Application number	US-202016833563-A
Country	US
Kind code	B2
Filing date	Mar 28, 2020
Priority date	Apr 15, 2016
Publication date	Jan 24, 2023
Grant date	Jan 24, 2023

Abstract

Ballistic resistant composite materials having high positive buoyancy in water are provided. More particularly, provided are foam-free, buoyant composite materials fabricated using dry processing techniques. The materials comprise fibrous plies that are partially coated with a particulate binder that is thermopressed to transform a portion of the binder into raised, discontinuous patches bonded to fiber/tape surfaces, while another portion of the particulate binder remains on the fibers/tapes as unmelted particles. The presence of the unmelted binder particles maintains empty spaces within the composite materials which increases the positive buoyancy of the composites in water.

First claim

What is claimed is:

1. A ballistic resistant material comprising at least one fibrous ply, each fibrous ply comprising a plurality of fibers and/or a plurality of tapes, wherein one or more of said fibers/tapes have surfaces that are partially covered by raised, discontinuous patches of a polymeric binder bonded to and extending from the fiber/tape surfaces, and wherein the material further comprises a plurality of polymer particles on and/or between said fibers/tapes, wherein said patches of the polymeric binder and said polymer particles comprise different polymers and wherein at least some of said polymer particles are unsoftened.

2. The ballistic resistant material of claim 1 wherein the patches have an aspect ratio of less than 10:1 and are formed on the fiber/tape surfaces by softening and/or partially melting a dry, solvent-free polymeric powder, wherein said patches are flattened powder particles in the form of raised bumps that extend from the fiber/tape surfaces, and wherein the polymer forming the patches has not been heated enough to flow from its original location of application.

3. The ballistic resistant material of claim 1 wherein said unsoftened polymer particles are unmelted.

4. The ballistic resistant material of claim 1 wherein each fibrous ply comprises a plurality of adjacent, unidirectional, parallel fibers and/or a plurality of adjacent, unidirectional, parallel tapes, and wherein said particles are both on and between said fibers/tapes.

5. The ballistic resistant material of claim 1 wherein less than 50% of the surface area of each of said fibers/tapes is covered by said patches.

6. The ballistic resistant material of claim 1 wherein each fibrous ply is non-woven and comprises a plurality of adjacent, unidirectional, parallel fibers/tapes, and wherein from 2% to 20% of the surface area of each of said fibers/tapes is covered by said polymeric binder.

7. The ballistic resistant material of claim 1 wherein each fibrous ply has a fiber areal density of less than 80 g/m 2 and a total areal density of less than 100 g/m 2 .

8. The ballistic resistant material of claim 5 wherein the patches of polymeric binder and the plurality of polymer particles combined comprise about 6 wt. % or less by weight of the ballistic resistant material, and wherein said particles have an average particle size of from about 100 μm to about 200 μm.

9. A multilayer composite comprising a plurality of consolidated plies of the ballistic resistant material of claim 1 , wherein said plies have been consolidated under heat and pressure, and wherein at least some of said polymer particles are unsoftened and not bonded to the fiber surfaces.

10. The multilayer composite of claim 9 wherein said composite has an interior empty space volume of at least 20% of the volume of said composite.

11. A ballistic resistant material comprising:
a) a plurality of non-woven plies, each ply comprising a plurality of adjacent, unidirectional fibers and/or a plurality of adjacent, unidirectional tapes, wherein one or more of said fibers/tapes have surfaces that are partially covered by discontinuous patches of a polymeric binder bonded to the fiber/tape surfaces; each ply having an outer top surface and an outer bottom surface; and
b) at least one thermoplastic overlay bonded to at least one surface of at least one of said plies, wherein said at least one thermoplastic overlay only partially covers said at least one surface, and wherein said at least one thermoplastic overlay has a melting point below a melting point of said polymeric binder, and wherein the material further comprises a plurality of polymer particles on and between said fibers/tapes, wherein said patches of the polymeric binder and said polymer particles comprise different polymers.

12. The ballistic resistant material of claim 11 wherein the thermoplastic overlay comprises a non-woven, discontinuous adhesive web, wherein at least some of said polymer particles are unsoftened and not bonded to the fiber surfaces and wherein said particles have an average particle size of from about 50 μm to about 700 μm.

13. The ballistic resistant material of claim 11 wherein the thermoplastic overlay comprises one or more binding elongate bodies having a melting point below a melting point of said polymeric binder.

14. The ballistic resistant material of claim 12 wherein the non-woven plies are consolidated and wherein said ballistic resistant material has a volume that partially comprises empty space, wherein said empty space comprises greater than 20% of said ballistic resistant material.

15. The ballistic resistant material of claim 14 wherein said material has a fiber areal density of less than about 80 g/m 2 .

16. The ballistic resistant material of claim 11 wherein the thermoplastic overlay comprises a non-woven, discontinuous adhesive web; wherein at least some of said polymer particles are unsoftened and not bonded to the fiber surfaces; wherein the patches have an aspect ratio of less than 10:1 and are formed on the fiber/tape surfaces by softening and/or melting a dry, solvent-free polymeric powder, and wherein said unsoftened polymer particles are unmelted and have an average particle size of from about 80 μm to about 500 μm.

17. The ballistic resistant material of claim 11 wherein at least some of said polymer particles are unsoftened, wherein said unsoftened polymer particles are unmelted and are not bonded to the fiber surfaces, wherein said particles are both on and between said fibers/tapes, and wherein said patches are flattened powder particles in the form of raised bumps that extend from the fiber/tape surfaces.

Assignees

• Honeywell Int Inc

Inventors

• Bhatnagar Ashok
• Bartelt Tyler
• Ardiff Henry Gerard
• Kratzer Gary
• Hurst David A
• Wagner Lori L

Classifications

• B32B2262/0223

  Vinyl resin fibres · CPC title

• B32B7/12

  using interposed adhesives or interposed materials with bonding properties · CPC title

• B32B2262/0284

  Polyethylene terephthalate [PET] or polybutylene terephthalate [PBT] · CPC title

• F41H1/02 Primary

  Armoured or projectile- or missile-resistant garments; Composite protection fabrics {(F41H5/04 takes precedence)} · CPC title

• B32B2307/54

  Yield strength; Tensile strength · CPC title