Segmented flexible gel composites and rigid panels manufactured therefrom
The present invention describes various methods for manufacturing gel composite sheets using segmented fiber or foam reinforcements and gel precursors. Additionally, rigid panels manufactured from the resulting gel composites are also described. The gel composites are relatively flexible enough to be wound and when unwound, can be stretched flat and made into rigid panels using adhesives.
1. A process comprising the steps of:
providing a segmented reinforcement sheet comprising a segmented fiber reinforcement sheet or a segmented open-cell foam reinforcement sheet; the segmented reinforcement sheet having a length, a width shorter than the length, and a thickness; the segmented reinforcement sheet being segmented partially through the thickness continuously across the entire width and substantially perpendicular to the length;
combining the segmented reinforcement sheet with a gel precursor;
gelling the gel precursor in the segmented reinforcement sheet to make a segmented reinforced gel composite sheet; and
drying the segmented reinforced gel composite sheet to make a reinforced aerogel composite sheet.
2. The process of claim 1 further comprising the step of applying an adhesive to at least one face of the reinforced aerogel composite sheet and attaching it to another planar material.
3. The process of claim 1 , further comprising the steps of:
providing the reinforced aerogel composite sheet of claim 1 with at least two major surfaces and multiple segmented cross-sectional surfaces;
applying an adhesive to at least one surface of said reinforced aerogel composite sheet; and
attaching the reinforced aerogel composite sheet to another aerogel composite sheet.
4. The process of claim 1 wherein the segmented reinforcement sheet has a facing layer or sheet attached to it.
5. The process of claim 4 wherein facing layer comprises fibers.
6. The process of claim 1 wherein the segmented reinforcement sheet comprises a segmented fiber reinforcement sheet which comprises non-continuous fibers.
7. The process of claim 1 further comprising the step of incorporating additives into the gel precursor, the additives selected from the group consisting of titanium dioxide, iron oxides, carbon black, graphite, aluminum hydroxide, phosphates, borates, metal silicates, metallocenes, molybdates, stannates, hydroxides, carbonates, zinc oxides, aluminum oxides, antimony oxides, magnesium-zinc blends, magnesium-zinc-antimony blends, silicon carbide, molybdenum silicide, manganese oxides, iron titanium oxide, zirconium silicate, zirconium oxide, iron (II) oxide, iron (III) oxide, manganese dioxide, iron titanium oxide (ilmenite), chromium oxide and a combination thereof.
8. The process of claim 1 , wherein the segmented reinforcement sheet comprises a segmented fiber reinforcement sheet, and the process further comprising the step of adding at least a binder to the fibers of the fiber reinforcement sheet or using a fiber reinforcement sheet comprising at least one binder.
9. The process of claim 1 , wherein at least a segment of the segmented reinforcement material is rigid.
10. The process of claim 1 , wherein the gel precursor comprises a material selected from the group consisting of zirconia, yttria, hafnia, alumina, titania, ceria, silica, polyacrylates, polystyrenes, polyacrylonitriles, polyurethanes, polyimides, polyfurfural alcohol, phenol furfuryl alcohol, melamine formaldehydes, resorcinol formaldehydes, cresol formaldehyde, phenol formaldehyde, polyvinyl alcohol dialdehyde, polycyanurates, polyacrylamides, various epoxies, agar, and agarose and combinations thereof.
11. The process of claim 1 wherein the segmented reinforcement sheet comprises a segmented fiber reinforcement sheet comprising materials selected from the group consisting of mineral wool, glass wool, fiber glass, polyester, polyolefin terephthalates, poly(ethylene) naphthalate, polycarbonates, cellulose fiber, aliphatic polyamides, cotton based polyester-polyurethanes, Carbon based fibers, graphite, polyacrylonitrile (PAN), oxidized PAN, uncarbonized heat treated PAN, fiberglass based material, E-glass, silica based fibers, quartz, Polyaramid fibers, polyolefins, polypropylene fibers, fluoropolymers, polytetrafluoroethylene (PTFE), Silicon carbide fibers, ceramic, Acrylic polymers, fibers of wool, silk, hemp, leather, suede, poly(p-phenylene-2,6-benzobisoxazole) (PBO), Liquid crystal material, Polyurethanes, polyamaides, Wood fibers, Boron, Aluminum, Iron, Stainless Steel fibers, polyether ether ketone (PEEK), polyether sulfone (PES), polyetherimide (PE1), polyether ketone (PEK), poly(p-phenylene sulfide) (PPS) and combinations thereof.
12. The process of claim 3 wherein the adhesive is selected from the group consisting of potassium water glass, sodium water glass, cement and alkali-activated aluminosilicates, polyethylene, kapton, polyurethane, polyester, natural rubber, synthetic rubber, hypalon, plastic alloys, PTFE, polyvinyl halides, polyester, neoprene, acrylics, nitriles, EPDM, EP, viton, vinyls, vinyl-acetate, ethylene-vinyl acetate, styrene, styrene-acrylates styrene-butadienes, polyvinyl alcohol, polyvinylchloride, acrylamids, phenolics and combinations thereof.
13. The process of claim 1 , wherein the thermal conductivity of the reinforced aerogel composite sheet is less than 25 mW/mK at ambient conditions.
14. The process of claim 1 , further comprising the step of rolling the segmented reinforced gel composite sheet prior to drying into a roll having an axis, and wherein the rolling of the gel composite sheet is such that gaps formed between the segments face away from the axis of the roll and extend parallel to the axis of the roll.
15. A reinforced aerogel composite sheet made by the process of claim 1 .
16. A panel comprising at least two layers of reinforced aerogel composites wherein at least one layer comprises the reinforced aerogel composite sheet of claim 15 .
17. The panel of claim 16 , further comprising an adhesive, wherein the adhesive is selected from the group consisting of potassium water glass, sodium water glass, cement and alkali-activated aluminosilicates, polyethylene, kapton, polyurethane, polyester, natural rubber, synthetic rubber, hypalon, plastic alloys, PTFE, polyvinyl halides, polyester, neoprene, acrylics, nitriles, EPDM, EP, viton, vinyls, vinyl-acetate, ethylene-vinyl acetate, styrene, styrene-acrylates styrene-butadienes, polyvinyl alcohol, polyvinylchloride, acrylamids, phenolics and combinations thereof.
18. The reinforced aerogel composite sheet of claim 15 , wherein the thermal conductivity of the reinforced aerogel composite is less than 25 mW/mK at ambient conditions.
19. The panel of claim 16 , wherein the thermal conductivity of the reinforced aerogel composite is less than 25 mW/mK at ambient conditions.