Method of Producing High-Strength Composite Sheet Composed of Fiber-Reinforced Grown Biological Matrix

Abstract

The present invention discloses a method of forming high-strength composite sheets composed of a fiber-reinforced biological matrix. This invention discloses three aspects of technology: fiber placement, biological matrix growth, and material insertion within a biological matrix. A cell culture is grown in a tank of nutrients. The cells form a skin and can envelope fibers that are positioned at a specific location. When taken out of its solution, it dries pinning the fibers into the sheet to form a lightweight, waterproof layer. By creating mostly axial fibers and rolling them into a tube, extremely strong structural cylinders can be formed. By incorporating a mesh of fibers (woven or knit) an extremely tough layer is formed that can be stacked and made into ballistic armor. The addition of foreign additives; graphite, metal powder may increase the strength, performance, and conductivity of the material.

Claims

1. A fiber-reinforced biological material (biological matrix) comprising: a. a cell culture in a solution that can be grown into a single sheet of biological matrix; b. a tank containing the cell culture capable of holding fiber reinforcement at an exact position so that it is encapsulated into the growing biological matrix; c. fiber-reinforcement that is inserted in a rack maintaining tension to maximize the strength of the sheet; d. fibers that are compressed into a plane as the biological matrix dries and shrinks in the vertical dimension; e. strengthened biological matrix as a result of the addition of particles to the cell culture that are incorporated into the biological matrix; f. a strong insulating layer once the biological matrix is dried; g. a conductive layer with the addition of conductive materials that reduce the resistivity of the biological matrix; h. a controlled growth period, followed by drying, allowing precise control of the thickness of the resulting dried sheet of biological matrix, including extremely thin sheets with a very high ratio of fiber to biological matrix; i. protection of the sheet from environmental degradation by gluing it in layers and coating with a protective chemical or glue; j. the creation of a mold of a desired shape, applying a chemical that allows the biological matrix to release easily; and k. a multi-layer composite material composed of layers of biological matrix each enveloping fiber reinforcement, and bonded by adhesive.

2. The method of claim 1 wherein the cell culture is a Symbiotic Colony of Bacteria and Yeast (SCOBY).

3. The method of claim 1 wherein the cell culture is a bacterial colony.

4. The method of claim 1 wherein the cell culture is a culture of plant cells or animal cells.

5. The method of claim 1 where the fiber reinforcement is high-modulus artificial fibers such as aramid, carbon fiber, or fiberglass.

6. The method of claim 1 where the fiber reinforcement is natural fibers such as jute or hemp.

7. The method of claim 1 where the fiber reinforcement is a tough material such as spider silk, which can be produced by genetically modified organisms.

8. The method of claim 1 where the density of the biological matrix is decreased, and the strength increased, by incorporating light, strong particles such as graphite, graphene, or carbon nanotubes into the solution so that they are incorporated by the cell culture into the biological matrix.

9. The method of claim 1 where graphene paint (conductive coating) is applied after the biological matrix is dried to create a conductive surface useful for electromagnetic shielding or to connect embedded circuitry to the biological matrix; the solvents can kill the biological cells so the paint must be applied either post-processing in a separate tank or at low concentrations so that the culture can survive and continue to grow around the conductive coating;

10. The method of claim 1 where metals such as silver and copper are added to the surface to create a conductive coating useful as electromagnetic shielding; since these materials are toxic to the biological matrix, they must be added in a separate tank.

11. A means of growing the fiber-reinforced biological matrix comprising: a. a tank holding nutrients and cells being grown into a biological matrix; b. a rack holding reinforcing fibers in tension in the cell culture while the biological matrix grows around them; c. a mechanism to lift the rack in and out of the tank; d. a roll-to-roll mechanism to grow infinite-length sheets of biological matrix by slowly drawing them through a long tank while maintaining tension; e. a washing mechanism to remove the remaining live cells and slime from the surface of the biological matrix; f. a drying mechanism for controlled rate of drying under tension so the biological matrix has a precise, predictable dimension; g. a boiler to create a sterile solution to feed the growing biological matrix; h. rollers that can compress and join multiple layers of biological matrix into a thicker sheet; i. a hydroponic system to deliver nutrients such as caffeine, sugar, or any other chemical or organic compound to increase the rate of growth or quality of the biological matrix; j. a sprayer to evenly distribute solutions containing additives on the surface or from beneath to be incorporated into the biological matrix; and k. a sterilization system so that no unwanted bacteria form around the biological matrix.

Description

DRAWINGS

[0016] FIG. 1 illustrates a tank containing SCOBY with a frame holding pre-tensioned aramid fibers.

[0017] FIG. 2 illustrates a batch system in which the sheet is grown with aramid fibers and then rolled onto a spool.

[0018] FIG. 3 illustrates a roll-to-roll system in which the fiber reinforcement is continuously pulled through the tank.

[0019] FIG. 4 illustrates a system for washing, drying, and collecting the composite sheet on a spool.

[0020] FIG. 5 illustrates a second tank where nutrients and conductive material is added to the surface.

DETAILED DESCRIPTION AND BEST MODE OF IMPLEMENTATION

[0021] FIG. 1 shows a tank 1 filled with a nutrient solution and cell culture 6, with a biological film 5 growing near the surface, with fibers 3 stretched on a frame 4 using hooks 2 to maintain the tension of the fiber reinforcement. Because it is under tension, the resulting sheet will have low strain (will not dramatically stretch under load).

[0022] Fibers can be spun into thicker ropes with most of the fiber in the axial direction and fewer across to create structural material with strength mostly in the axial direction.

[0023] Fiber reinforcement can be woven using a loom with varying spacing of fibers in both warp and weft directions to precisely control strength in a plane. Fiber can be knit, creating loops that can stretch and absorb impact. Fiber can be crocheted, using only one strand, to create a structure that is three dimensional allowing connections between layers via the stronger fibers rather than only the dried cell material. This should make the material more resistant to delamination and also the energy of impacts may be more diffused.

[0024] FIG. 2 shows a batch system in which a tank 1 contains nutrients 6 and cell culture with embedded fiber 10 being lifted out of the tank with rollers 8,9 and rolled onto a spool 7.

[0025] FIG. 3 shows a tank 1 containing nutrient solution 6 with incoming fiber reinforcement 3 tensioned and moved by rollers 8, outgoing biological composite with fiber reinforcement 9, going into final processing cleaning and drying (10). The dried sheet is collected on the receiving spool 7.

[0026] FIG. 4 shows the hidden details of the previous process 10 (cleaning and drying). Wet biological composite with fiber reinforcement 9 comes through the rollers 8 to be washed with the water and cleaning solution supply 11 using the water and cleaning solution dispenser 12. The cleaned biological matrix with fiber reinforcement is then passed through the drying unit comprised of the heating source 14 and the heating supply 13. The dried biological matrix with fiber reinforcement is then collected on the receiving spool 7.

[0027] FIG. 5 shows the dispensing conductive material/powder 15 which is held in the conductive material/powder holder 16 which is then programmably dispersed by the conductive material/powder dispenser 17. The conductive material/powder holder 16 runs on rails 19 on wheels 18 along the edge of the tank 1. The nutrient solution tank 21 disperses nutrient evenly through nutrient/solution supply pipes 20.

REFERENCE NUMBERS

[0028] 1. Tank [0029] 2. Tensioning Hooks [0030] 3. Fiber [0031] 4. Frame [0032] 5. Biological composite [0033] 6. Nutrient Solution for biological growth [0034] 7. Receiving Spool [0035] 8. Rollers [0036] 9. Biological composite with fiber reinforcement [0037] 10. Opening towards final processing, cleaning, drying. [0038] 11. Water and cleaning solution supply [0039] 12. Water and cleaning solution dispenser [0040] 13. Electrical or gas supply for heating/drying. [0041] 14. Heating source [0042] 15. Conductive material/powder [0043] 16. Conductive material/powder holder [0044] 17. Conductive material/powder dispenser [0045] 18. Wheels [0046] 19. Rails [0047] 20. Nutrient/solution supply pipes [0048] 21. Nutrient/solution tank