Nonaqueous sol-gel systems for enhancing adhesion of water-sensitive materials

Abstract

To provide sol-gels, methods for forming sol-gels, and vehicle components including sol-gel coating systems.SOLUTION: A sol-gel comprises the reaction product of: an organosilane; a metal alkoxide; an acid stabilizer; and an organic solvent, the sol-gel having 1 wt.% or less of water content based on the total weight of the sol-gel. The metal alkoxide is zirconium (IV) tetramethoxide, zirconium (IV) tetraethoxide, or the like. The organosilane is 2-(3,4-epoxycyclohexyl)ethyltrimethoxysilane, 2-(3,4-epoxycyclohexyl)ethyltriethoxysilane, or the like.SELECTED DRAWING: None

Description

[Technical field]

[0001] The present disclosure provides sol-gels, sol-gel films, and substrates, such as vehicle components, upon which the sol-gel films are disposed. [Background technology]

[0002] Aircraft surfaces are typically made of metal, such as aluminum or titanium. To prevent or reduce corrosion, a primer may be coated onto the metal surface. To further improve adhesion of the primer to the metal surface, an adhesive coating is usually placed between the metal surface and the primer.

[0003] An adherent sol-gel film may be placed at the interface between the metal and the primer. The adherent sol-gel film typically contains more than 90% water by weight, and often more than 95% water by weight. Water as a solvent for the sol-gel is environmentally benign, reduces the amount of waste generated, and has the ability to hydrolyze silanes present in the sol-gel. While typical sol-gels of this type are effective for corrosion resistance of metals such as titanium or nickel, other materials such as low alloy steels are not resistant to corrosion in the presence of water-based sol-gels. Additionally, there may be cases where the sol-gel must be applied near water-sensitive materials or components, or in internal recessed or pocket areas where water exposure or water entrapment may be prevalent.

[0004] Thus, there is a need in the art for new and improved adherent sol-gel films suitable for use with steel substrates. Summary of the Invention

[0005] The present disclosure provides sol-gels, sol-gel films, and substrates, such as vehicle components, on which the sol-gel films are disposed. At least one sol-gel is formed by combining a metal alkoxide, an acid stabilizer, and an organic solvent to form a first mixture having a water content of about 10% by weight or less, based on the total weight of the first mixture, and combining the first mixture with an organosilane to form a second mixture having a water content of about 10% by weight or less, based on the total weight of the first mixture.

[0006] The at least one sol-gel is a reaction product of an organosilane, a metal alkoxide, an acid stabilizer, and an organic solvent, and the sol-gel has a water content of about 10 weight percent or less, based on the total weight of the sol-gel.

[0007] At least one vehicle component includes a sol-gel coating system including a metal substrate and a sol-gel disposed on the metal substrate, the sol-gel being a reaction product of an organosilane, a metal alkoxide, an acid stabilizer, and an organic solvent, the sol-gel having a water content of about 10 wt% or less based on a total weight of the sol-gel. [Brief description of the drawings]

[0008] So that the above-mentioned features of the present disclosure may be understood in detail, a more particular description of the present disclosure, briefly summarized above, may be had by reference to embodiments, some of which are illustrated in the accompanying drawings. It should be noted, however, that since the present disclosure admits of other equally effective embodiments, the attached drawings illustrate only typical embodiments of the present disclosure and therefore should not be considered as limiting the scope of the present disclosure.

[0009] [Figure 1] FIG. 2 illustrates a side view of a corrosion-inhibiting sol-gel disposed on a substrate in accordance with at least one embodiment of the present disclosure. [Diagram 2] FIG. 1 is a perspective view of a rotor blade according to at least one embodiment of the present disclosure. [Diagram 3] FIG. 1 is a flow diagram of a method of forming a sol-gel in accordance with at least one embodiment of the present disclosure. [Figure 4A] 1 is a magnified image showing bondline crack growth in an untreated alloy steel specimen, according to at least one embodiment of the present disclosure. [Figure 4B] 1 is a magnified image showing bondline crack growth for a test specimen treated with a 5% water version of the present invention, in accordance with at least one embodiment of the present disclosure. [Diagram 5] 1 is a graph illustrating crack growth test results comparing a process control specimen, which is a test blade having a sol-gel disposed thereon, to a grit blasted test blade that does not have a sol-gel disposed thereon, in accordance with at least one embodiment of the present disclosure. [Figure 6] 1 is a graph illustrating dry and submerged floating roller peel test results comparing a pitch horn with 0 wt. % aqueous sol-gel formulation disposed thereon to a grit blasted test blade with no sol-gel disposed thereon, in accordance with at least one embodiment of the present disclosure; [Figure 7A-F] FIG. 7A is an image of a grit blasted 4130 low alloy steel panel according to at least one embodiment of the present disclosure. FIG. 7B is an image of a grit blasted 4130 low alloy steel panel according to at least one embodiment of the present disclosure. FIG. 7C is an image of a grit blasted 4130 low alloy steel panel with an aqueous sol-gel disposed thereon according to at least one embodiment of the present disclosure. FIG. 7D is an image of a grit blasted 4130 low alloy steel panel with an aqueous sol-gel disposed thereon according to at least one embodiment of the present disclosure. FIG. 7E is an image of a grit blasted 4130 low alloy steel panel with a non-aqueous sol-gel disposed thereon according to at least one embodiment of the present disclosure. FIG. 7F is an image of a grit blasted 4130 low alloy steel panel with a non-aqueous sol-gel disposed thereon according to at least one embodiment of the present disclosure.

[0010] To facilitate understanding, the same reference numbers have been used, where possible, to designate identical elements that are common to multiple figures. The drawings are not drawn to scale and may be simplified for clarity. It is contemplated that elements and features of one embodiment may be beneficially incorporated in other embodiments without further description. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0011] The present disclosure provides sol-gels, sol-gel films, and substrates, such as vehicle components, on which the sol-gel films are disposed. At least one sol-gel is formed by combining a metal alkoxide, an acid stabilizer, and an organic solvent to form a first mixture having a water content of about 10% by weight or less, based on the total weight of the first mixture, and combining the first mixture with an organosilane to form a second mixture having a water content of about 10% by weight or less, based on the total weight of the first mixture.

[0012] The at least one sol-gel is a reaction product of an organosilane, a metal alkoxide, an acid stabilizer, and an organic solvent, and the sol-gel has a water content of about 10 weight percent or less, based on the total weight of the sol-gel.

[0013] At least one vehicle component includes a sol-gel coating system including a metal substrate and a sol-gel disposed on the metal substrate, the sol-gel being a reaction product of an organosilane, a metal alkoxide, an acid stabilizer, and an organic solvent, the sol-gel having a water content of about 10 wt% or less based on a total weight of the sol-gel.

[0014] The sol-gels and vehicle components of the present disclosure provide improved corrosion resistance of a substrate, such as a vehicle component, on which the sol-gels of the present disclosure are disposed. For example, a steel vehicle component having a sol-gel having a moisture content of 10% by weight or less disposed thereon has improved floating roller abrasion resistance properties (ASTM D3167) compared to a steel vehicle component having a conventional sol-gel formulation disposed thereon.

[0015] [Sol-gel] The term "sol-gel" is a contraction of "solution-gelation" and refers to the reaction product of a series of reactions in which soluble metal species (typically metal alkoxides or metal salts) hydrolyze to form metal hydroxides. The metal hydroxides can then form heterometallic bonds, e.g., Si-O-Zr. In the absence of an organic acid, a white precipitate, e.g., Zr(OH)2, forms rapidly when a metal alkoxide is added to water. Zr(OH)2 is not soluble in water and prevents sol-gel formation. Adding an acid to the metal alkoxide allows for water-based systems. The ratio of organic to inorganic in the polymer matrix is ​​controlled to maximize the performance of the sol-gel, such as its adhesive ability, for a particular application.

[0016] Organosilane: In at least one embodiment, the weight fraction (wt %) of the organosilane in the sol-gel is from about 0.1 wt % to about 20 wt %, such as from about 0.3 wt % to about 15 wt %, such as from about 0.5 wt % to about 10 wt %, such as from about 0.7 wt % to about 5 wt %, such as from about 1 wt % to about 2 wt %, such as about 1 wt %, about 1.5 wt %, about 2 wt %.

[0017] In at least one embodiment, the organosilane of the present disclosure has formula (I): TIFF0007673122000001.tif32170In the above formula, R 2 , R 3 and R 4 each independently represents a linear or branched C 1-20 It is an alkyl group. 1-20 Alkyl includes methyl, ethyl, propyl, butyl, pentyl, hexyl, heptyl, octyl, nonyl, decyl, undecyl, dodecyl, tridecyl, tetradecyl, pentadecyl, hexadecyl, heptadecyl, octadecyl, nonadecyl, and icosanyl; R 1 is selected from alkyl, cycloalkyl, ether, and aryl. Alkyl is a linear or branched C 1-20 Contains alkyl.1-20 Alkyl includes methyl, ethyl, propyl, butyl, pentyl, hexyl, heptyl, octyl, nonyl, decyl, undecyl, dodecyl, tridecyl, tetradecyl, pentadecyl, hexadecyl, heptadecyl, octadecyl, nonadecyl, and icosanyl. Ethers include polyethylene glycol ethers, polypropylene glycol ethers, C1-C 20 Includes alkyl ethers, aryl ethers, and cycloalkyl ethers.

[0018] In at least one embodiment, the ether is selected from the following: TIFF0007673122000002.tif216170

[0019] In the above formula, n is a positive integer. In at least one embodiment, n is a positive integer, and the number average molecular weight (Mn) of the ether is about 300 to about 500, for example, about 375 to about 450, for example, about 400 to about 425.

[0020] In at least one embodiment, the organosilane is a hydroxyorganosilane. Hydroxyorganosilanes are substantially unreactive to nucleophiles, such as some corrosion inhibitors. In at least one embodiment, the hydroxyorganosilanes of the present disclosure have the formula (II): TIFF0007673122000003.tif32170 (wherein R is selected from alkyl, cycloalkyl, ether, and aryl. Alkyl is a linear or branched C 1-20 Contains alkyl. 1-20 Alkyl includes methyl, ethyl, propyl, butyl, pentyl, hexyl, heptyl, octyl, nonyl, decyl, undecyl, dodecyl, tridecyl, tetradecyl, pentadecyl, hexadecyl, heptadecyl, octadecyl, nonadecyl, and icosanyl. Ethers include polyethylene glycol ethers, polypropylene glycol ethers, C1-C 20 Includes alkyl ethers, aryl ethers, and cycloalkyl ethers.

[0021] In at least one embodiment, the ether is selected from the following: TIFF0007673122000004.tif214170

[0022] In the above formula, n is a positive integer. In at least one embodiment, n is a positive integer, and the number average molecular weight (Mn) of the ether is about 300 to about 500, for example, about 375 to about 450, for example, about 400 to about 425.

[0023] In at least one embodiment, the organosilane is Compound 1 or Compound 2: TIFF0007673122000005.tif102170

[0024] In at least one embodiment, the organosilane is selected from the group consisting of 3-aminopropyltriethoxysilane, 3-glycidoxy-propyltriethoxysilane, p-aminophenyltrimethoxysilane, p-aminophenyltriethoxysilane, allyltrimethoxysilane, allyltriethoxysilane, n-(2-aminoethyl)-3-aminopropyltrimethoxysilane, 3-aminopropyltriethoxysilane, 3-aminopropyltrimethoxysilane, 3-glycidoxypropyldiisopropylethoxysilane, (3-glycidoxypropyl)methyldiethoxysilane, 3-glycidoxypropyltrimethoxysilane, 2-(3,4-epoxycyclohexyl)ethyltrimethoxysilane, 2-(3,4-epoxycyclohexyl)ethyltriethoxysilane, 3-mercaptopropyltrimethoxysilane, 3-mercaptopropyltriethoxysilane, 3-methacryloxypropyl and n-phenylaminopropyltrimethoxysilane, vinylmethyldiethoxysilane, 3-methacryloxypropylmethyldimethoxysilane, 3-methacryloxypropyltrimethoxysilane, n-phenylaminopropyltrimethoxysilane, vinylmethyldiethoxysilane, vinyltriethoxysilane, vinyltrimethoxysilane, bis(trimethoxysilyl)ethane, bis(triethoxysilyl)ethane, bis[3-(trimethoxysilyl)propyl]amine, bis[3-(triethoxysilyl)propyl]amine, bis[3-(triethoxysilyl)propyl]disulfide, bis[3-(trimethoxysilyl)propyl]disulfide, bis[3-(triethoxysilyl)propyl]trisulfide, bis[3-(trimethoxysilyl)propyl]trisulfide, bis[3-(triethoxysilyl)propyl]trisulfide, bis[3-(trimethoxysilyl)propyl]tetrasulfide, and bis[3-(trimethoxysilyl)propyl]tetrasulfide.

[0025] In at least one embodiment, organosilanes useful in forming the sol-gels of the present disclosure provide electrophilic silicon and / or epoxide moieties that can react with a nucleophile, such as a hydroxy-containing nucleophile, In at least one embodiment, the organosilanes of the present disclosure provide sol-gels with reduced porosity and blistering as compared to conventional sol-gels.

[0026] Metal Alkoxides: Metal alkoxides useful in forming the sol-gels of the present disclosure provide metal atoms coordinated in the sol-gel for adhesion and mechanical strength. Metal alkoxides of the present disclosure include at least one of zirconium alkoxides, titanium alkoxides, hafnium alkoxides, yttrium alkoxides, cerium alkoxides, and lanthanum alkoxides. Metal alkoxides can have four alkoxy ligands coordinated to a metal having an oxidation number of +4. Non-limiting examples of metal alkoxides include zirconium(IV) tetramethoxide, zirconium(IV) tetraethoxide, zirconium(IV) tetra-n-propoxide, zirconium(IV) tetra-isopropoxide, zirconium(IV) tetra-n-butoxide, zirconium(IV) tetra-isobutoxide, zirconium(IV) tetra-n-pentoxide, zirconium(IV) tetra-isopentoxide, zirconium(IV) tetra-n-hex ... zirconium(IV) tetra-isohexoxide, zirconium(IV) tetra-n-heptoxide, zirconium(IV) tetra-isoheptoxide, zirconium(IV) tetra-n-octoxide, zirconium(IV) tetra-n-isooctoxide, zirconium(IV) tetra-n-nonooxide, zirconium(IV) tetra-n-isononoxide, zirconium(IV) tetra-n-decyloxide, and zirconium(IV) tetra-n-isodecyloxide.

[0027] In at least one embodiment, the weight fraction (wt %) of the metal alkoxide in the sol-gel is about 0.1 wt % to about 10 wt %, for example, about 0.2 wt % to about 5 wt %, for example, about 0.3 wt % to about 3 wt %, for example, about 0.4 wt % to about 2 wt %, for example, about 0.5 wt % to about 1 wt %, for example, about 0.2 wt %, about 0.5 wt %, about 1 wt %.

[0028] Corrosion Inhibitors: Corrosion inhibitors useful in forming the sol-gel of the present disclosure provide corrosion resistance (against water) for metal substrates placed adjacent to the sol-gel. The corrosion inhibitors of the present disclosure are compounds having one or more thiol moieties. Metallic aircraft surfaces may include steel or alloys having a major component such as aluminum and a minor component known as an intermetallic compound. For example, intermetallic compounds often contain copper metal, which is prone to corrosion. Without being bound by theory, it is believed that the interaction of the thiol moiety of the corrosion inhibitor of the present disclosure with the copper-containing intermetallic compound of the metal surface (e.g., an aluminum alloy surface) prevents corrosion of the metal surface. More specifically, the interaction of the thiol moiety of the corrosion inhibitor of the present disclosure with the intermetallic compound blocks the reduction of the intermetallic compound by slowing the rate of oxygen reduction and reducing the oxidation of the metal alloy, such as an aluminum alloy.

[0029] In at least one embodiment, the corrosion inhibitor of the present disclosure is an organic compound that contains a disulfide group and / or a thiolate group (e.g., a metal sulfide bond). In at least one embodiment, the corrosion inhibitor has the formula: 1 --S n --X--R 2 (In the formula, R 1 is an organic group, n is an integer of 1 or more, X is a sulfur or metal atom, and R 2 R is an organic group. 1 and R 2 wherein one or both of the groups may contain additional polysulfide groups and / or thiol groups. Further, in at least one embodiment, the corrosion inhibitor may be represented by the formula -(R 1 --S n --X--R 2 ) q -(In the formula, R 1 is an organic group, n is a positive integer, X is a sulfur or metal atom, R 2 is an organic group and q is a positive integer. In at least one embodiment, R (of the polymeric or monomeric corrosion inhibitor) 1 and R 2is independently selected from H, alkyl, cycloalkyl, aryl, thiol, polysulfide, or thione. 1 and R 2 Each of may be independently substituted with a moiety selected from alkyl, amino (phosphorus-containing), ether, alkoxy, hydroxy (sulfur-containing), selenium, or tellurium. 1 and R 2 Each of R has 1 to 24 carbon and / or non-hydrogen atoms. For example, R 1 and R 2 Examples of heterocyclic rings of groups include azoles, triazoles, thiazoles, dithiazoles and / or thiadiazoles.

[0030] In at least one embodiment, the corrosion inhibitor comprises a metal in a metal-thiolate complex. The corrosion inhibitor may comprise a metal center and one or more thiol groups (ligands) bound to and / or coordinated to the metal center with a metal-sulfide bond. Thiolates are derivatives of thiols in which a metal atom replaces the hydrogen bonded to sulfur. Thiolates are compounds in which M is a metal and R 1 is an organic group represented by the general formula MSR 1 R 1 can contain a disulfide group. Metal-thiolate complexes can be represented by the general formula M-(SR 1 ) n where n is generally an integer from 2 to 9, and M is a metal atom. The metal is copper, zinc, zirconium, aluminum, iron, cadmium, lead, mercury, silver, platinum, palladium, gold, and / or cobalt.

[0031] In at least one embodiment, the corrosion inhibitor comprises an azole compound. Examples of suitable azole compounds include cyclic compounds having one nitrogen atom, such as pyrrole, two or more nitrogen atoms, such as pyrazole, imidazole, triazole, tetrazole and pentazole, one nitrogen atom and one oxygen atom, such as oxazole and isoxazole, and one nitrogen atom and one sulfur atom, such as thiazole and isothiazole. Non-limiting examples of suitable azole compounds include 2,5-dimercapto-1,3,4-thiadiazole, 1H-benzotriazole, 1H-1,2,3-triazole, 2-amino-5-mercapto-1,3,4-thiadiazole (also known as 5-amino-1,3,4-thiadiazole-2-thiol), 2-amino-1,3,4-thiadiazole. In at least one embodiment, for example, the azole may be 2,5-dimercapto-1,3,4-thiadiazole. In at least one embodiment, the azole may be present in the composition at a concentration of 1 g / L of the sol-gel composition to 0.01 g / L of the sol-gel composition, such as 0.4 g / L of the sol-gel composition. In some embodiments, the azole compound comprises benzotriazole and / or 2,5-dimercapto-1,3,4-thiadiazole.

[0032] The corrosion inhibitors of the present disclosure include heterocyclic thiols and amines that can provide elimination of oxygen reduction. Heterocyclic thiols include thiadiazoles having one or more thiol moieties. Non-limiting examples of thiadiazoles having one or more thiol moieties are represented by formula (III) or formula (IV): TIFF0007673122000006.tif33170

[0033] Thiadazoles of formula (III) can be purchased from Vanderbilt Chemicals, LLC (Norwalk, Connecticut) and are known as Vanlube® 829. Thiadazoles of formula (IV) can be purchased from WPC Technologies, Inc. (Oak Creek, Wisconsin). TM It can be purchased from InhibiCor TMIt is known as the 1000.

[0034] The corrosion inhibitors of the present disclosure may be derivatives of 2,5-dimercapto-1,3,4 thiadiazole, designated by the symbol HS-CN2SC-SH or "DMTD", and selected derivatives of trithiocyanuric acid ("TMT"), used in applications as corrosion inhibitors in association with paints. Examples include 2,5-dimercapto-1,3,4 thiadiazole (DMTD) and 2,4-dimercapto-s-triazolo-[4,3-b]-1,3-4-thiadiazole, as well as trithiocyanuric acid (TMT). Other examples include N-, S-, and N,N-, S,S-, and N,S-substituted derivatives of DMTD, such as 5-mercapto-3-phenyl-1,3,4-thiadiazoline-2-thione or bismuthiol II (3-phenyl-1,3,4-thiadiazolidine-2,5-dithione), as well as various S-substituted derivatives of trithiocyanuric acid. Other examples include 5,5'dithio-bis(1,3,4 thiadiazole-2(3H)-thione or (DMTD)2 or polymers of DMTD (DMTD); 5,5'thio-bis(1,3,4 thiadiazole-2(3H)-thione; or dimers and polymers of TMT (TMT)2. Other examples include those of the general formula: M(DMTD) n where n=1, 2 or 3 and M is a metal cation such as Zn(II), Bi(III), Co(II), Ni(II), Cd(II), Pb(II), Ag(I, Sb(III), Sn(II), Fe(II) or Cu(II) (e.g., ZnDMTD, Zn(DMTD)2, Bi(DMTD)3); similar salts of TMT in a 1:1 ratio, e.g., ZnTMT; and similarly soluble Li(I), Ca(II), Sr(II), Mg(II), La(III), Ce(III), Pr(III) or Zr(IV) salts. Additional examples include salts of the general formula M[(DMTD)] n ] mwhere n=2 or n>2, m=1, 2 or 3, and M is a metal cation, e.g., M=Zn(II), Bi(III), Co(II), Ni(II), Cd(II), Pb(II), Ag(I), Sb(III), Sn(II), Fe(II) or Cu(II). Typical examples are Zn[(DMTD)2], Zn[(DMTD)2]2.

[0035] Additional examples include DMTD, (DMTD) n or 5,5'thio-bis(1,3,4 thiadiazole-2(3H)-thione or 2,4-dimercapto-s-triazolo-[4,3-b]-1,3-4-thiadiazole. Typical examples include cyclohexylamine:DMTD in ratios of 1:1 and 2:1; di-cyclohexylamine:DMTD in ratios of 1:1 and 2:1; aniline:DMTD in ratios of 1:1 and 2:1; analogous salts of TMT (e.g. di-cyclohexylamine):TMT in a ratio of 1:1. Further examples include DMTD or (DMTD) formed with polyamines. n and polyammonium salts of TMT.

[0036] Further examples include intrinsically conductive polyanilines doped with DMTD or (DMTD)2 or 5,5'thio-bis(1,3,4 thiadiazole-2(3H)-thione and TMT; intrinsically conductive polypyrroles and / or polythiophenes doped with DMTD, (DMTD)2 and 5,5'thio-bis(1,3,4 thiadiazole-2(3H)-thione and / or TMT.

[0037] Further examples include polyDMTD / polyaniline, polyDMTD / polypyrrole and polyDMTD / polythiophene micro- or nanocomposites; similar micro- or nanocomposites with TMT and with 5,5'thio-bis(1,3,4 thiadiazole-2(3H)-thione); DMTD or salts of DMTD or derivatives of DMTD and TMT as organic components of various pigment grade inorganic matrices or physical mixtures. In some embodiments, such inorganic matrices contain non-toxic anionic and cationic species with corrosion inhibitor properties, such as MoO4, respectively. - , PO4 - , HPO3 - , Poly-phosphate, BO2 - , SiO4 - , N.C.N. - , WO4 - , phosphomolybdate, phosphotungstate, and Mg, Ca, Sr, La, Ce, Zn, Fe, Al, Bi.

[0038] Further examples include DMTD or salts of DMTD or derivatives of DMTD and TMT in encapsulated form (such as inclusion complexes in various polymer matrices or cyclodextrin inclusion complexes) or in microencapsulated form.

[0039] Pigment grade forms of DMTD include Zn(DMTD)2 and Zn-DMTD (among other organic and inorganic salts of the former) with inorganic products or corrosion inhibitor pigments, such as phosphates, molybdates, borates, silicates, tungstates, phosphotungstates, phosphomolybdates, cyanamides or carbonates, and oxides of the aforementioned cationic species. Examples include zinc phosphate, cerium molybdate, calcium silicate, strontium borate, zinc cyanamide, cerium phosphotungstate, ZnO, CeO2, ZrO2, and amorphous SiO2.

[0040] In at least one embodiment, the corrosion inhibitor is a lithium ion and a counterion that includes various ions known to form salts with lithium. Non-limiting examples of counterions suitable for forming salts with lithium include carbonates, hydroxides, and silicates (e.g., orthosilicates and metasilicates). For example, in at least one embodiment, the corrosion inhibitor includes a lithium carbonate, lithium hydroxide, or a lithium silicate (e.g., lithium orthosilicate or lithium metasilicate). Furthermore, in at least one embodiment, the counterion includes various ions known to form salts with other Group IA (or Group 1) metals (e.g., Na, K, Rb, Cs, and / or Fr). Non-limiting examples of counterions suitable for forming salts with alkali metals include carbonates, hydroxides, and silicates (e.g., orthosilicates and metasilicates). For example, in at least one embodiment, the corrosion inhibitor includes an alkali metal carbonate, an alkali metal hydroxide, or an alkali metal silicate (e.g., an alkali metal orthosilicate or an alkali metal metasilicate). For example, some non-limiting examples of suitable salts include carbonates, hydroxides, and silicates (eg, orthosilicates or metasilicates) of sodium, potassium, rubidium, cesium, and francium.

[0041] The corrosion inhibitors of the present disclosure include aluminum and magnesium rich compounds that can provide cathodic protection for a material. The corrosion inhibitors of the present disclosure may also include cesium compounds.

[0042] Acid stabilizer: The acid stabilizer used to form the sol-gel of the present disclosure provides stabilization of the metal alkoxide and corrosion inhibitor (if present) of the sol-gel, as well as reducing the pH of the sol-gel. The pH value of the sol-gel (and the composition forming the sol-gel) can be controlled by the use of an acid stabilizer. The acid stabilizer of the present disclosure includes organic acids. Organic acids include acetic acid (e.g., glacial acetic acid) or citric acid. Acid stabilizers with relatively low acidity (e.g., pKa greater than the pKa of acetic acid), such as glycol, ethoxyethanol, or H2NCH2CH2OH, can also be used.

[0043] In at least one embodiment, the pH of the sol-gel of the present disclosure is about 2 to about 5, for example, about 3 to about 4. In at least one embodiment, the weight fraction (wt%) of the acid stabilizer in the sol-gel is about 0.1 wt% to about 10 wt%, for example, about 0.2 wt% to about 5 wt%, for example, about 0.3 wt% to about 3 wt%, for example, about 0.4 wt% to about 2 wt%, for example, about 0.5 wt% to about 1 wt%, for example, about 0.1 wt%, about 0.2 wt%, about 0.3 wt%, about 0.4 wt%, about 0.5 wt%. In at least one embodiment, the weight percentage of the acid stabilizer and the weight percentage of the metal alkoxide in the sol-gel are about 0.6 wt% or more. In another embodiment, the weight percentage of the acid stabilizer and the weight percentage of the metal alkoxide in the sol-gel are less than 0.6 wt%. Preferably, the ratio of metal alkoxide to acid stabilizer in the sol-gel is from about 1:1 to about 3:1, for example, about 2:1.

[0044] When a corrosion inhibitor is present in the sol-gel, the molar ratio of acid stabilizer to metal alkoxide can be from about 1:1 to about 40:1, such as from about 3:1 to about 8:1, such as from about 4:1 to about 6:1, such as from about 4:1 to about 5:1.

[0045] Without being bound by theory, these ratios of acid stabilizer not only contribute to stabilizing the metal alkoxide against hydrolysis, but also protonate the thiol moieties of the corrosion inhibitor (if present), thereby reducing or preventing reaction of the corrosion inhibitor (e.g., with the metal alkoxide).

[0046] [solvent] One or more sol-gel components of the present disclosure may be dissolved in one or more solvents before being added to a mixture containing other sol-gel components. For example, corrosion inhibitors generally have limited solubility in water and aqueous solvents. The corrosion inhibitor may be an insoluble powder, an insoluble material (e.g., an aggregate, solid and / or liquid), a hydrophobic compound, heavy oil and / or grease. Thus, the sol-gel components may be dissolved in a compatible solvent or suspended, emulsified and / or dispersed in an incompatible solution and / or solvent. Solvents suitable for dissolving, suspending, emulsifying and / or dispersing the sol-gel components of the present disclosure are polar organic and / or non-polar organic.

[0047] Polar organic solvents are advantageous for dissolving sol-gel components such as corrosion inhibitors. Additionally or alternatively, the sol-gel components can be suspended, emulsified and / or dispersed in the solvent. Examples of organic solvents for dissolving, suspending, emulsifying and / or dispersing the sol-gel components include at least one of alcohol (e.g., ethanol or propanol), ethylene glycol, propylene glycol, polyethylene glycol, polypropylene glycol, ether (e.g., dimethyl ether or dipropylene glycol dimethyl ether), glycol ether, tetrahydrofuran (THF), N-methyl-2-pyrrolidone (NMP), and dimethyl sulfoxide (DMSO). In at least one embodiment, the organic solvent is selected from at least one of ethanol, n-propanol, isopropanol, 1-butanol, 2-butanol, 1-pentanol, 2-pentanol, 3-pentanol, 1-hexanol, 2-hexanol, and 3-hexanol. The organic solvent of the present disclosure may be anhydrous, e.g., 99% or higher purity. In at least one embodiment, the sol-gel formulation has about 50% to about 99% by weight of organic solvent, e.g., about 60% to about 97% by weight, e.g., about 80% to about 95% by weight, e.g., about 90% to about 95% by weight, e.g., about 95%, about 96%, about 97%, about 98%, about 99% by weight, based on the total weight of the sol-gel formulation. Curing, e.g., heating, of the mixture containing the sol-gel components can remove some or all of the solvent from the sol-gel / mixture.

[0048] In at least one embodiment, the weight percentage (wt %) of (metal alkoxide + organosilane + acid stabilizer) in the mixture is about 0.1 wt % to about 30 wt %, such as about 0.3 wt % to about 20 wt %, such as about 1 wt % to about 10 wt %, such as about 1 wt % to about 5 wt %, such as about 2 wt % to about 4 wt %, such as about 2 wt % to about 3 wt %, such as about 1 wt %, about 1.5 wt %, about 2 wt %, about 2.5 wt %, about 3 wt %.

[0049] [Sol-gel] The sol-gel of the present disclosure comprises an organic solvent and has a water content of about 0.1% to about 10% by weight, e.g., about 0.1% to about 10% by weight, e.g., about 0.1% to about 5% by weight, e.g., about 0.1% to about 3% by weight, e.g., about 0.1% to about 1% by weight, e.g., about 0.1% to about 0.5% by weight. In at least one embodiment, the sol-gel has a water content of 0.5% by weight or less, e.g., 0.3% by weight or less, e.g., 0% by weight or less. It has been discovered that sol-gels having, for example, 1% by weight or less water, in addition to maintaining or improving corrosion resistance (e.g., reducing flash rust), form sol-gels having sufficient adhesion capabilities to substrates, such as steel substrates, when compared to conventional sol-gels containing, for example, 90% by weight or more water.

[0050] In at least one embodiment, the weight fraction (wt%) of (metal alkoxide + hydroxyorganosilane + acid stabilizer) in the sol-gel is about 0.3 wt% to about 50 wt%, for example, about 1 wt% to about 45 wt%, for example, about 2 wt% to about 40 wt%, for example, about 3 wt% to about 35 wt%, for example, about 4 wt% to about 25 wt%, for example, about 8 wt% to about 22 wt%, for example, about 10 wt%, about 12 wt%, about 15 wt%. The greater the amount of (metal alkoxide + hydroxyorganosilane + acid stabilizer), the greater the amount of corrosion inhibitor present in the sol-gel. The weight fraction (wt%) of the corrosion inhibitor in the sol-gel is about 0.1 wt% to about 50 wt%, for example, about 0.2 wt% to about 40 wt%, for example, about 0.5 wt% to about 35 wt%, for example, about 1 wt% to about 30 wt%, for example, about 2 wt% to about 25 wt%, for example, about 3 wt% to about 20 wt%, for example, about 4 wt%, about 5 wt%, about 7 wt%, about 10 wt%, or about 15 wt%.

[0051] [Sol-gel system] 1 is a side view of a corrosion-inhibiting sol-gel system 100 that includes a sol-gel 102 disposed on a material substrate 104. The sol-gel 102 has corrosion-inhibiting properties that provide corrosion protection for the material substrate 104. The sol-gel 102 promotes adhesion between the metal substrate 104 and a secondary layer 106. The secondary layer 106 can be a sealant, adhesive, primer, or paint that can be deposited on the sol-gel 102 by, for example, spray drying.

[0052] The material substrate 104 may be any suitable material and / or may include any suitable structure that would benefit from the sol-gel 102 deposited thereon. The metal substrate 104 may be one or more components (e.g., structural or mechanical components) of an apparatus exposed to the environment, such as an aircraft, watercraft, spacecraft, land vehicle, equipment, civil structures, fasteners, and / or other apparatus susceptible to environmental degradation. The material substrate 104 may be part of a larger structure, such as a vehicle component. The vehicle component is any suitable component of a vehicle, for example, a structural component such as an aircraft landing gear, panel, joint, etc. Examples of vehicle components include rotor blades, landing gear, auxiliary power units, aircraft noses, fuel tanks, tail cones, panels, coated lap joints between two or more panels, wing-fuselage assemblies, structural aircraft composites, fuselage body-joints, wing rib-to-skin joints, and / or other internal components. The material substrate 104 can be made of at least one of aluminum, aluminum alloys, magnesium, magnesium alloys, nickel, iron, iron alloys, steel, titanium, titanium alloys, copper and copper alloys, as well as glass / silica and other inorganic or mineral substrates. In at least one embodiment, the material substrate 104 is made of steel. The material substrate 104 may be a "bare" substrate (unplated metal) with no plating, conversion coating and / or corrosion protection between the material substrate 104 and the sol-gel 102. Additionally or alternatively, the material substrate 104 may include surface oxidation and / or hydroxylation. Thus, the sol-gel 102 may be bonded directly to the material substrate 104 and / or a surface oxide layer on the surface of the material substrate 104. In at least one embodiment, the material is not water sensitive, but the sol-gel disposed on the material may protect other adjacent structures that may be water sensitive.

[0053] The secondary layer 106 is disposed on a second surface 110 of the sol-gel 102 opposite the first surface 108 of the sol-gel 102. In at least one embodiment, the sol-gel 102 has a thickness that is less than the thickness of the material substrate 104. In at least one embodiment, the sol-gel 102 has a thickness of about 1 μm (micron) to about 500 nm, such as about 5 μm to about 100 nm, such as about 10 μm to about 100 μm. Thinner coatings have fewer defects (and are more likely to be defect-free), but thicker coatings may provide more wear, electrical, and / or thermal protection to the underlying material substrate 104.

[0054] In at least one embodiment, the secondary layer 106 comprises an organic material (e.g., an organic chemical composition) configured to bond and / or adhere to the sol-gel 102. The secondary layer 106 may be a paint, a topcoat, a polymer coating (e.g., an epoxy coating and / or a urethane coating), a polymeric material, a composite material (e.g., a filled composite material and / or a fiber reinforced composite material), a laminate material, or a mixture thereof. In at least one embodiment, the secondary layer 106 comprises at least one of a polymer, a resin, a thermosetting polymer, a thermoplastic polymer, an epoxy, a lacquer, a polyurethane, and a polyester. The secondary layer 106 may additionally comprise at least one of a pigment, a binder, a surfactant, a diluent, a solvent, a particulate (e.g., a mineral filler), a corrosion inhibitor, and a fiber (e.g., carbon, aramid, and / or glass fiber).

[0055] In at least one embodiment, the layer of material 104 is a pitch horn of a rotor blade. A rotor blade of the present disclosure comprises one or more rotor blade components. As described herein, a "rotor blade component" comprises any suitable structure suitable for forming a rotor blade in combination with one or more other rotor blade components. FIG. 2 is a perspective view of a rotor blade according to some embodiments of the present disclosure. As shown in FIG. 2, a rotor blade 200 of a main rotor assembly (not shown) is made of a root section 202, a middle section 204, and a tip section 206. The root section 202 is connected to a pitch horn 216. Each of the sections 202, 204, 206 is of any suitable shape to match the aerodynamic properties of the rotor blade to the speed increase along the rotor blade's span. The tip section 206 of the rotor blade comprises an angular shape such as anhedral, cathedral, gull, bend, etc. Rotor blade portions 202 , 204 , 206 define a span of rotor blade 200 along a longitudinal axis P between first edge 12 and second edge 214 between the axis of rotation A and the distal end 210 of tip portion 206 .

[0056] [Method of forming sol-gel] The method of forming the sol-gel of the present disclosure includes mixing a metal alkoxide, acetic acid, and an organic solvent, such as an anhydrous organic solvent, followed by stirring for about 1 minute to about 1 hour, such as about 30 minutes. Additional organic solvent (e.g., about 1% to 20% by volume, such as 5% by volume of the total volume) is then added to the metal alkoxide / acetic acid mixture. An organosilane is then added to the mixture and stirred for about 1 minute to about 1 hour, such as about 30 minutes. Optionally, a corrosion inhibitor is added to the mixture. The mixture can be deposited on a material substrate. The deposited mixture can be cured at ambient temperature or heated to speed up the curing / sol-gel formation.

[0057] 3 is a flow diagram illustrating a method 300 of forming a sol-gel 102. In block 302, the sol-gel 102 may be formed by mixing one or more sol-gel components. The sol-gel components include two or more of an organosilane, a metal alkoxide, an acid stabilizer, and optionally a corrosion inhibitor. In block 308, curing the mixed components forms the sol-gel 102.

[0058] Generally, the mixing step 302 is carried out by combining (e.g., dispersing, emulsifying, suspending and / or dissolving) the sol-gel formulation components in an organic solvent, preferably an anhydrous organic solvent, and optionally stirring the sol-gel formulation.

[0059] The mixing step 302 includes mixing the sol-gel components to form a mixture (e.g., a solution, mixture, emulsion, suspension, and / or colloid). In at least one embodiment, the mixing step 302 includes mixing all the sol-gel components simultaneously. Alternatively, the mixing step 302 includes mixing any two components (e.g., a metal alkoxide and an acid stabilizer in an organic solvent) to form a first mixture, and then mixing the remaining components into the first mixture to form a second mixture. The first mixture and the second mixture each have a water content of about 0.1% to about 10% by weight, such as about 0.1% to about 5% by weight, such as about 0.1% to about 3% by weight, such as about 0.1% to about 1% by weight, such as about 0.1% to about 0.5% by weight, such as 0.5% by weight or less, such as 0.3% by weight or less, such as 0.1% by weight or less, such as 0% by weight or less.

[0060] The mixing step 302 may include dissolving, suspending, emulsifying and / or dispersing the sol-gel components in an organic solvent prior to mixing with one or more other sol-gel components. Examples of solvents for dissolving, suspending, emulsifying and / or dispersing the sol-gel components include one or more of alcohols (e.g., ethanol or propanol), ethylene glycol, propylene glycol, polyethylene glycol, polypropylene glycol, ethers (e.g., dimethyl ether or dipropylene glycol dimethyl ether, glycol ether, tetrahydrofuran (THF)), N-methyl-2-pyrrolidone (NMP), and dimethyl sulfoxide (DMSO). In at least one embodiment, the organic solvent is one or more of ethanol, n-propanol, isopropanol, 1-butanol, 2-butanol, 1-pentanol, 2-pentanol, 3-pentanol, 1-hexanol, 2-hexanol, and 3-hexanol. The organic solvents of the present disclosure may be anhydrous, e.g., 99% or greater purity. In at least one embodiment, the sol-gel formulation has from about 50% to about 99% by weight, such as from about 60% to about 97% by weight, such as from about 80% to about 95% by weight, such as from about 90% to about 95% by weight, such as about 95% by weight, about 96% by weight, about 97% by weight, about 98% by weight, about 99% by weight of organic solvent based on the total weight of the sol-gel formulation.

[0061] Additionally or alternatively, the mixing step 302 may include mixing one or more sol-gel components that are solids, aggregates, and / or powders with one or more other sol-gel components. For example, if the mixing step 302 includes mixing solids, powders, and / or viscous liquids, the mixing step 302 may include mixing with a high shear mixer (e.g., a paint shaker or a planetary agitator or stirrer). A high shear mixer may be advantageous for breaking down and / or finely dispersing solids to form a substantially uniform mixture. For example, a high shear mixer may dissolve, suspend, emulsify, disperse, homogenize, deagglomerate, and / or disintegrate solids in the sol-gel formulation.

[0062] The sol-gel components during the mixing step 302 can be diluted to control the self-condensation reaction, thereby extending the pot life of the mixed sol-gel formulation. The mixing step 302 can include mixing, in which the weight percentage (wt%) of (metal alkoxide+organosilane+acid stabilizer) in the mixture is about 0.1 wt% to about 30 wt%, such as about 0.3 wt% to about 20 wt%, such as about 1 wt% to about 10 wt%, such as about 1 wt% to about 5 wt%, such as about 2 wt% to about 4 wt%, such as about 2 wt% to about 3 wt%, such as about 1 wt%, about 1.5 wt%, about 2 wt%, about 2.5 wt%, about 3 wt%.

[0063] The mixing step 302 can include mixing, wherein the weight percentage (wt %) of the corrosion inhibitor in the mixture is about 0.1 wt % to about 50 wt %, such as about 0.2 wt % to about 40 wt %, for example, about 0.5 wt % to about 35 wt %, for example, about 1 wt % to about 30 wt %, for example, about 2 wt % to about 25 wt %, for example, about 3 wt % to about 20 wt %, for example, about 4 wt %, about 5 wt %, about 7 wt %, about 10 wt %, about 15 wt %. In at least one embodiment, the sol-gel formulation contains a corrosion inhibitor and the mixing step 302 can include mixing, wherein the weight percentage (wt %) of (metal alkoxide+organosilane+acid stabilizer) in the mixture is from about 0.3 wt % to about 50 wt %, such as from about 1 wt % to about 45 wt %, such as from about 2 wt % to about 40 wt %, such as from about 3 wt % to about 35 wt %, such as from about 4 wt % to about 25 wt %, such as from about 8 wt % to about 22 wt %, such as about 10 wt %, about 12 wt %, about 15 wt %.

[0064] In at least one embodiment, the molar ratio of acid stabilizer to metal alkoxide in the sol-gel formulation during mixing step 302 is from about 1:1 to about 40:1, such as from about 3:1 to about 8:1, such as from about 4:1 to about 6:1, such as about 2:1.

[0065] The mixture of sol-gel components can be incubated (304), for example, for about 1 minute to about 60 minutes, for example, for about 5 minutes to about 30 minutes, for example, for about 10 minutes to about 20 minutes. Additionally, the pot life is the time from mixing to when the sol-gel is formed (e.g., when the mixture becomes too viscous to use). The pot life can be from about 1 hour to about 24 hours, for example, from about 2 hours to about 8 hours, for example, about 4 hours. The incubation step 304 can be carried out under ambient conditions (e.g., room temperature) and / or at elevated temperatures. Suitable incubation temperatures include from about 10°C to about 100°C, for example, from about 20°C to about 70°C, for example, from about 30°C to about 50°C, for example, about 40°C.

[0066] In at least one embodiment, the method 300 includes coating the material substrate 104 with the mixture including the sol-gel components (block 306) and incubating the mixture (block 304). The incubation step 304 includes mixing the mixture including the sol-gel components and then leaving the mixture including the sol-gel components at room temperature for about 30 minutes or more. The coating step 306 can include wetting the material substrate 104 with the mixture including the sol-gel components, for example, by spraying, dipping, brushing and / or wiping the mixture including the sol-gel components onto the material substrate 104. For example, suitable forms of spraying include a spray gun, a high volume low pressure spray gun and / or a hand pump sprayer. The mixture including the sol-gel components is drained from the wet material substrate 104 for several minutes (e.g., 1-30 minutes, 1-10 minutes, or 3-10 minutes), and excess undrained mixture can be sucked off the material substrate 104 and / or gently blown off the material substrate 104 by compressed air, as needed.

[0067] In at least one embodiment, the coating step 306 includes cleaning and / or pre-treating the material substrate 104 before wetting it with a mixture containing sol-gel components. In general, the sol-gel 102 adheres and / or bonds better to a clean bare material substrate that is substantially free of dirt, non-reactive surface oxides and / or corrosion products and preferably has a sufficient concentration of reactive hydroxyl groups or other chemically reactive species. The material substrate surface preparation method may include degreasing, alkaline cleaning, chemical etching, chemical deoxidation, mechanical deoxidation (e.g., sanding and / or polishing) and / or other suitable approaches to creating a sol-gel compatible surface. The coating step 306 typically does not include coating the metal substrate 104 with an undercoat or forming a conversion coating on the metal substrate 104, unless a coating is applied to create hydroxyl-rich or otherwise improved compatibility with the sol-gel. The material substrate surface can be made hydroxyl-rich by depositing silica hydroxylate on the material surface.

[0068] In at least one embodiment, the method of the present disclosure includes curing the mixture including the sol-gel components. As shown in FIG. 3, the curing step 308 may include drying the mixture including the sol-gel components disposed on the material substrate 104 and may be performed under ambient conditions (i.e., room temperature) and / or at an elevated temperature. In at least one embodiment, the curing temperature is about 10 o C~about 150 o C, for example, about 30 o C ~ about 100 o C, for example, about 50 o C ~ about 90 o C, for example, about 60 o C, about 70 o C, about 80 o C. The curing step 308 can be carried out for a certain period of time, for example, from about 1 minute to about 48 hours, for example, from about 5 minutes to about 24 hours, for example, from about 10 minutes to about 8 hours, for example, from about 30 minutes to about 4 hours, for example, about 1 hour.

[0069] After the coating step 306 and / or the curing step 308, the sol-gel is suitable for exposure to an external environment and / or application of a secondary layer 106. As shown in Figure 3, in block 310, a step of depositing a secondary layer 106 of an organic material can be performed before the curing step 308 is fully completed, for example, the step of depositing the secondary layer 106 (in block 310) is performed at least partially simultaneously with the curing step 308. The depositing step 310 can include painting, spraying, dipping, contacting, adhering and / or bonding the sol-gel 102 with an organic material to form the secondary layer 106. The secondary layer can include paint, fiber reinforced plastic, or other suitable organic material.

[0070] [Aspects] Article 1. combining a metal alkoxide, an acid stabilizer, and an organic solvent to form a first mixture having a water content of about 10% by weight or less, based on a total weight of the first mixture; and mixing an organosilane with the first mixture to form a second mixture having a water content of about 10% by weight or less based on the total weight of the second mixture; The sol-gel formed by

[0071] Clause 2 2. The sol-gel of clause 1, wherein the mixing to form the first mixture comprises dispersing, emulsifying, suspending or dissolving the metal alkoxide and the acid stabilizer in the organic solvent.

[0072] Article 3. 3. The sol-gel of clause 1 or 2, further comprising incubating the second mixture at a temperature of about 10° C. to about 100° C.

[0073] Article 4. 4. The sol-gel of any one of clauses 1 to 3, further comprising curing the second mixture at a temperature of about 10° C. to about 150° C.

[0074] Article 5. 5. The sol-gel of any one of clauses 1 to 4, further comprising depositing the first mixture or the second mixture onto a metal substrate.

[0075] Article 6. 6. The sol-gel of clause 5, further comprising cleaning the metal substrate by degreasing, alkaline cleaning, chemical etching, chemical deoxidation or mechanical deoxidation of the metal surface prior to deposition.

[0076] Article 7. 7. The sol-gel of clause 5 or 6, wherein the metal substrate is a vehicle component.

[0077] Article 8. 8. The sol-gel of clause 7, wherein the vehicle component is one or more of a rotor blade, an auxiliary power unit, an aircraft nose, a fuel tank, a tail cone, a panel, a coated lap joint between two or more panels, a wing-fuselage assembly, an aircraft structural composite, a fuselage joint, and a wing rib-skin joint.

[0078] Article 9. 9. The sol-gel of any one of clauses 5 to 8, wherein the metal substrate comprises aluminum, aluminum alloys, nickel, iron, iron alloys, steel, titanium, titanium alloys, copper, and copper alloys.

[0079] Article 10. 10. The sol-gel of any one of clauses 5 to 9, wherein the metal substrate is steel.

[0080] Article 11. 11. The sol-gel of any one of clauses 1 to 10, further comprising depositing a secondary layer on the sol-gel.

[0081] Article 12. 12. The sol-gel of any one of clauses 1 to 11, wherein mixing the metal alkoxide and the acid stabilizer is carried out by successively depositing the metal alkoxide on the metal substrate and depositing the acid stabilizer on the metal substrate.

[0082] Article 13. 13. The sol-gel of any one of clauses 1 to 12, wherein the first mixture and the second mixture have a water content of about 0.1 wt.% to about 5 wt.%, based on the total weight of the first mixture and the second mixture, respectively.

[0083] Article 14. 14. The sol-gel of any one of clauses 1 to 13, wherein the first mixture and the second mixture have a water content of about 0.1 wt.% to about 3 wt.%, based on the total weight of the first mixture and the second mixture, respectively.

[0084] Article 15. 15. The sol-gel of any of clauses 1 to 14, wherein the first mixture and the second mixture have a water content of about 1 wt % or less, based on the total weight of the first mixture and the second mixture, respectively.

[0085] Article 16. 16. The sol-gel of any of clauses 1 to 15, wherein the first mixture and the second mixture have a water content of about 0.5 wt % or less, based on the total weight of the first mixture and the second mixture, respectively.

[0086] Article 17. 17. The sol-gel of any one of clauses 1 to 16, wherein the organic solvent is one or more of an alcohol such as ethylene glycol, propylene glycol, polyethylene glycol, polypropylene glycol, an ether such as tetrahydrofuran, N-methyl-2-pyrrolidone, and dimethylsulfoxide.

[0087] Article 18. 18. The sol-gel according to any one of the preceding clauses, wherein the organic solvent is an alcohol, which is ethanol, n-propanol, isopropanol, 1-butanol, 2-butanol, 1-pentanol, 2-pentanol, 3-pentanol, 1-hexanol, 2-hexanol or 3-hexanol.

[0088] Article 19. 19. The sol-gel of any one of clauses 1 to 18, wherein the organic solvent is anhydrous.

[0089] Article 20. 20. The sol-gel of any one of clauses 1 to 19, wherein the first mixture and the second mixture have an organic solvent content of about 50 wt% to about 99 wt%, based on the total weight of the first mixture and the second mixture, respectively.

[0090] Article 21. 21. The sol-gel of any one of clauses 1 to 20, wherein the first mixture and the second mixture have an organic solvent content of about 90 wt% to about 95 wt%, based on the total weight of the first mixture and the second mixture, respectively.

[0091] Article 22. Organosilanes; Metal alkoxides; Acid stabilizers; and Reaction products of organic solvents 1. A sol-gel comprising:

[0092] Article 23. 23. The sol-gel of clause 22, wherein the sol-gel has a water content of about 0.1% to about 5% by weight, based on the total weight of the sol-gel.

[0093] Article 24. 24. The sol-gel of clause 22 or 23, wherein the sol-gel has a water content of about 0.1% to about 3% by weight, based on the total weight of the sol-gel.

[0094] Article 25. 25. The sol-gel of any one of clauses 22 to 24, wherein the sol-gel has a water content of about 1 wt. % or less, based on the total weight of the sol-gel.

[0095] Article 26. 26. The sol-gel of any one of clauses 22 to 25, wherein the sol-gel has a water content of about 0.5 wt.% or less, based on the total weight of the sol-gel.

[0096] Article 27. 27. The sol-gel of any one of clauses 22 to 26, wherein the organic solvent is one or more of an alcohol, ethylene glycol, propylene glycol, polyethylene glycol, polypropylene glycol, ether, tetrahydrofuran, N-methyl-2-pyrrolidone, and dimethylsulfoxide.

[0097] Article 28. 28. The sol-gel according to any one of clauses 22 to 27, wherein the organic solvent is an alcohol which is ethanol, n-propanol, isopropanol, 1-butanol, 2-butanol, 1-pentanol, 2-pentanol, 3-pentanol, 1-hexanol, 2-hexanol or 3-hexanol.

[0098] Article 29. 29. The sol-gel of any one of clauses 22 to 28, wherein the organic solvent is anhydrous.

[0099] Article 30. Organosilanes include 3-aminopropyltriethoxysilane, 3-glycidoxypropyltriethoxysilane, p-aminophenyltrimethoxysilane, p-aminophenyltriethoxysilane, allyltrimethoxysilane, n-(2-aminoethyl)-3-aminopropyltrimethoxysilane, 3-aminopropyltriethoxysilane, 3-aminopropyltrimethoxysilane, 3-glycidoxypropyldiisopropylethoxysilane, (3-glycidoxypropyl)methyldiethoxysilane, 3-glycidoxypropyltrimethoxysilane, 3-mercaptopropyltrimethoxysilane, 3-mercaptopropyltriethoxysilane, 3-methacryloxypropylmethyldiethoxysilane, 3-methacryloxypropyltrimethoxysilane, 3-methacryloxypropyltriethoxy ... 30. The sol-gel of any one of clauses 22 to 29, which is one or more of acryloxypropylmethyldimethoxysilane, 3-methacryloxypropyltrimethoxysilane, n-phenylaminopropyltrimethoxysilane, vinylmethyldiethoxysilane, vinyltriethoxysilane, vinyltrimethoxysilane, bis[3-(triethoxysilyl)propyl]disulfide, bis[3-(trimethoxysilyl)propyl]disulfide, bis[3-(triethoxysilyl)propyl]trisulfide, bis[3-(trimethoxysilyl)propyl]trisulfide, bis[3-(triethoxysilyl)propyl]tetrasulfide or bis[3-(trimethoxysilyl)propyl]tetrasulfide.

[0100] Article 31. The organosilane has the formula: TIFF0007673122000007.tif32170 (in the above formula, R 2 , R 3 and R 4 each independently represents a linear or branched C 1-20 is alkyl, R 1 is alkyl, cycloalkyl, ether or aryl. 31. The sol-gel according to any one of clauses 22 to 30, represented by:

[0101] Article 32. R 1 , R2 , R 3 and R 4 32. The sol-gel formulation of clause 31, wherein each of is independently methyl, ethyl, propyl, butyl, pentyl, hexyl, heptyl, octyl, nonyl, decyl, undecyl, dodecyl, tridecyl, tetradecyl, pentadecyl, hexadecyl, heptadecyl, octadecyl, nonadecyl, and icosanyl.

[0102] Article 33. R 1 Polyethylene glycol ether, polypropylene glycol ether, C 1-20 32. The sol-gel formulation according to clause 31, wherein the ether is an alkyl ether, an aryl ether or a cycloalkyl ether.

[0103] Article 34. R, TIFF0007673122000008.tif184170 (where n is a positive integer) 32. The sol-gel according to claim 31, which is one of:

[0104] Article 35. The organosilane is 32. The sol-gel of clause 31, which is TIFF0007673122000009.tif47170.

[0105] Article 36. Metal alkoxides include zirconium(IV) tetramethoxide, zirconium(IV) tetraethoxide, zirconium(IV) tetra-n-propoxide, zirconium(IV) tetra-isopropoxide, zirconium(IV) tetra-n-butoxide, zirconium(IV) tetra-isobutoxide, zirconium(IV) tetra-n-pentoxide, zirconium(IV) tetra-isopentoxide, zirconium(IV) tetra-n-hexoxide, and zirconium(IV) tetra-isohexoxide. 36. The sol-gel of any one of clauses 22 to 35, wherein the sol-gel is one or more of zirconium(IV) tetra-n-heptoxide, zirconium(IV) tetra-isoheptoxide, zirconium(IV) tetra-n-octoxide, zirconium(IV) tetra-n-isooctoxide, zirconium(IV) tetra-n-nonooxide, zirconium(IV) tetra-n-isononoxide, zirconium(IV) tetra-n-decyloxide, zirconium(IV) tetra-n-isodecyloxide.

[0106] Article 37. 37. The sol-gel of any one of clauses 22 to 36, wherein the acid stabilizer is acetic acid.

[0107] Article 38. A vehicle component, Metal substrate and and a sol-gel according to any one of clauses 22 to 37 disposed on a metal substrate. A vehicle component including:

[0108] Article 39. 39. The vehicle component of clause 38, wherein the vehicle component is one or more of a rotor blade, an auxiliary power unit, an aircraft nose, a fuel tank, a tail cone, a panel, a coated lap joint between two or more panels, a wing-fuselage assembly, an aircraft structural composite, a fuselage joint, and a wing rib-skin joint.

[0109] Article 40. 39. The vehicle component of claim 38, wherein the metal substrate comprises aluminum, aluminum alloys, nickel, iron, iron alloys, steel, titanium, titanium alloys, copper, and copper alloys.

[0110] Article 41. 41. The vehicle component of clause 40, wherein the metal substrate comprises steel.

[0111] Article 42. 42. The vehicle component of any one of clauses 38 to 41, further comprising a secondary layer disposed on the sol-gel formulation.

[0112] Article 43. 43. The vehicle component of claim 42, wherein the secondary layer is an epoxy coating or a urethane coating. EXAMPLES

[0113] Experimental Materials: 3% AC-130-2 kit was obtained from 3M. 3% AC-131 kit was obtained from 3M. 3% AC-130-2 and 3% AC-131 are non-chromate conversion coatings for use on aluminum, nickel, stainless steel, magnesium, and titanium alloys, respectively. The kit has Part A, which is an aqueous mixture of acetic acid and zirconium tetra-n-propoxide (TPOZ), and Part B, which is GTMS. The two components are mixed together (Part A + Part B), and the molar ratio of silicon to zirconium in the mixture is 2.77:1. The molar ratio of acetic acid to TPOZ in Part A is 0.45:1. As used herein, the (TPOZ / GTMS / organosilane) combination may be referred to as a "bonding agent."

[0114] Glacial acetic acid (GAA) and glycidoxypropyl-trimethoxy-silane (GTMS) were obtained from Sigma Aldrich, UCT chemicals, Gelest, Inc., and / or Acros organics. Zirconium tetra-n-propoxide (TPOZ; 70% in n-propanol) was obtained from Sigma Aldrich or Gelest, Inc. The molar ratio of acetic acid to TPOZ is about 0.45:1.

[0115] The sol-gel formulation was placed on a panel, such as the pitch horn of a rotor blade. The pitch horn of the rotor blade comprises steel. All panels were grit blasted and blown with clean filtered air prior to depositing the sol-gel formulation on the panel. The sol-gel formulation was then incubated and allowed to cure.

[0116] method: Sol-gel formulation placed on blade pitch horn for fatigue testing A sol-gel formulation was made and applied to a fatigued blade pitch horn. Compared to the standard 3% 3MAC-131 sol-gel formulation, the formulation had reduced water and acetic acid content. After the first fatigued blade pitch horn was processed, a small amount of orange rust-like color was visible on the pitch horn and test panel. Thus, for the second fatigued blade, the amount of glacial acetic acid and metal alkoxide was reduced to 10% of those present in the standard 3% AC-131 formulation. Table 1 shows the weight contents of water, GTMS, TPOZ, and GAA, with the remainder being reagent grade isopropyl alcohol. TIFF0007673122000010.tif39170

[0117] 4A and 4B are images showing bondline crack growth of low alloy steel process control test specimens comparing a non-sol-gel treated specimen (FIG. 4A) with a 5% water version specimen (FIG. 4B) that was used to prepare test blade #2 for adhesive bonding. The examples shown in FIGS. 4A and 4B were exposed to 140° F. and 85-100% relative humidity during crack growth testing and then separated to reveal the extent of adhesive failure and crack growth. The panels with the cured 5% by weight water sol-gel placed thereon showed a significant reduction in crack growth and corrosion compared to the panels that were not treated with the formulation placed thereon. Nevertheless, the panels with the cured 5% by weight water sol-gel were observed to show some "flash rust" to the steel substrate material after treatment with the sol-gel and prior to bonding.

[0118] FIG. 5 is a graph showing crack growth test results (per ASTM D3762) comparing the sol-gel treated test coupons from Table 1 used on Test Blade #1 and Test Blade #2 with a grit blasted-only test coupon (labeled HP9-1 Grit Blast) that did not have the sol-gel disposed thereon. As shown in FIG. 5, the sol-gel containing examples showed much less stress crack growth compared to the untreated HP9-1 grit blasted specimens, although some "flash rust" was observed. The presence of "flash rust" even in formulations with low water (e.g., 5%) was one of the reasons low water content formulations (including formulations with 0% water) were tested.

[0119] Sol-gel formulations having low water content The Floating Roller Peel (FRP) test has several properties that are particularly advantageous for evaluating surface preparations for adhesive bonding. The results of the FRP test are presented as pounds per inch width ("piw"). Adhesive failure typically occurs at localized stress concentration areas of the bondline. The FRP test subjects the bondline to high stress concentration loads for the entire duration of the test, and therefore has the ability to detect susceptibility of the bond when exposed to high stress concentrations. Given that moisture resistance is a desired property achieved using the sol-gel process, the FRP test can also be modified to expose the bondline to moisture during testing. In each experiment described herein, three different FRP specimens were tested. One test was performed under standard room temperature, dry (RTD) conditions to obtain a baseline RTD test value. A second room temperature wet (RTW) test was performed with a constant room temperature deionized water spray on the peel bondline for the entire duration of the test. A third specimen was also tested using the water spray technique, but to provide more evidence as to moisture resistance, this specimen was first immersed in 160°F water for one week, followed by a shorter room temperature water immersion to allow the specimen to equilibrate at ambient temperature before being tested using the RTW water spray peel test.

[0120] Table 2 shows the floating roller peel test results of the sol-gel formulations of the present disclosure and the sol-gels formed from the sol-gel formulations. As shown in Table 2, the sol-gel formulations with 0 wt% water were able to form sol-gels on steel substrates with excellent FRP properties and were free of haze. This indicates that no Zr(OH)2 was formed in the sol-gel formulations. Precipitation and haze in the sol-gel formulations reduces the ability of the sol-gel to bond to metal surfaces. Interestingly, the haze and precipitation increased as the water content decreased from 5 or 6 wt% water content, but the haze and precipitation began to decrease when the water content was less than 1 wt%, e.g., 0 wt%. TIFF0007673122000011.tif231170TIFF0007673122000012.tif98170

[0121] In light of the 0 wt% water sol-gel formulation, additional sol-gel formulations (shown in Table 3) were tested with various amounts of metal alkoxide and glacial acetic acid. As shown in Table 3, the amount of TPOZ and GAA can be varied in the sol-gel formulations containing 0 wt% water, and after curing, the sol-gels formed have excellent FRP properties. These data indicate that the sol-gel formulations of the present disclosure provide improved moisture exposure capability, corrosion resistance, and better adhesive bond properties compared to conventional sol-gel compositions with higher water content, even when moisture exposure occurs at the bondline with metal. TIFF0007673122000013.tif135170

[0122] 6 is a graph illustrating the floating roller peel (FRP) test results of a pitch horn with 0 wt % aqueous sol-gel formulation placed thereon compared to a grit blasted test blade (labeled HP9-1 grit blast) with no sol-gel placed thereon. The floating roller peel test (ASTM D3167) was performed under the following test conditions: 1) Room temperature drying conditions 2) Room temperature with water spray on the peel bond line during testing 3) Wet conditioning before testing (160 o F Immersion in water for 1 week), followed by room temperature / water spray test

[0123] As shown in Figure 6, the pitch horn having sol-gel formed from 0 wt% aqueous sol-gel formulation disposed thereon has higher peel strength upon moisture exposure compared to the grit blast polishing method (HP9-1 grit blast). These data indicate that the sol-gel compositions of the present disclosure provide improved moisture exposure capability, corrosion resistance, and better adhesive bond properties compared to conventional sol-gel compositions having higher moisture content, even when moisture exposure occurs at the bond line with the metal.

[0124] 7A-7F are images comparing 4130 low alloy steel panels that were grit blasted according to at least one embodiment of the present disclosure, including a grit blast only panel (left, FIGS. 7A and 7B), grit blast followed by {1 min drench spray + air dry} with 3M AC-130-2 sol-gel (middle, FIGS. 7C and 7D), and grit blast followed by {1 min drench spray + air dry, with 0 wt. % aqueous sol-gel (right, FIGS. 7E and 7F). During spraying, the panels were tilted to allow the aqueous sol-gel or non-aqueous sol-gel to flow downwards, so that the top of each aqueous sol-gel panel was slightly less corroded than the bottom of each aqueous sol-gel panel. The images in FIGS. 7A-7F were taken approximately 1.5 hours after air drying, without any further moisture or heat exposure to the panels. As shown in Figures 7C and 7D, corrosion occurred on low alloy steel when treated with the aqueous AC-130-2 treatment. The 0 wt. % aqueous sol-gel prevents corrosion on the steel panel (right, Figures 7E and 7F).

[0125] [Definition] The term "alkyl" includes substituted or unsubstituted straight or branched chain alkyl groups containing from 1 to about 20 carbon atoms. In at least one embodiment, alkyl is a straight or branched chain C 1-20 Contains alkyl. 1-20 Alkyl includes methyl, ethyl, propyl, butyl, pentyl, hexyl, heptyl, octyl, nonyl, decyl, undecyl, dodecyl, tridecyl, tetradecyl, pentadecyl, hexadecyl, heptadecyl, octadecyl, nonadecyl, icosanyl, and structural isomers thereof.

[0126] The term "cycloalkyl" embraces substituted or unsubstituted cyclic alkyl groups containing from 3 to about 20 carbon atoms.

[0127] The term "aryl" refers to any monocyclic, bicyclic or tricyclic carbocyclic ring of up to 6 carbon atoms in each ring, where at least one ring is an aromatic or aromatic ring system of 5 to 14 carbon atoms containing a carbocyclic aromatic group fused to a 5- or 6-membered cycloalkyl group. Examples of aryl groups include, but are not limited to, phenyl, naphthyl, anthracenyl or pyrenyl.

[0128] The term "alkoxy" refers to RO--, where R is alkyl as defined herein. The terms alkyloxy, alkoxyl, and alkoxy can be used interchangeably. Examples of alkoxy include, but are not limited to, methoxyl, ethoxyl, propoxyl, butoxyl, pentoxyl, hexyloxyl, heptyloxyl, octyloxyl, nonyloxyl, decyloxy, and structural isomers thereof.

[0129] The term "heterocyclyl" refers to monocyclic, bicyclic, or tricyclic rings having up to 10 atoms in each ring, where at least one ring is aromatic and contains 1 to 4 heteroatoms in the ring selected from N, O, and S. Non-limiting examples of heterocyclyls include, but are not limited to, pyridyl, thienyl, furanyl, pyrimidyl, imidazolyl, pyranyl, pyrazolyl, thiazol, thiadiazolyl, isothiazolyl, oxazolyl, isoxazolyl, pyrrolyl, pyridazinyl, pyrazinyl, quinolinyl, isoquinolinyl, benzofuranyl, dibenzofuranyl, dibenzothiophenyl, benzothienyl, indolyl, benzothiazolyl, benzoxazolyl, benzimidazolyl, isoindolyl, benzotriazolyl, purinyl, thianaphthenyl, and pyrazinyl. Attachment of a heterocyclyl can occur through an aromatic ring or through a non-aromatic ring or a ring that does not contain a heteroatom.

[0130] The terms "hydroxy" and "hydroxyl" each refer to --OH.

[0131] "Non-aqueous" sol-gels include sol-gels having a water content of 10 wt% or less, such as from about 0.1 wt% to about 10 wt%, for example from about 0.1 wt% to about 5 wt%, for example from about 0.1 wt% to about 3 wt%, for example from about 0.1 wt% to about 1 wt%, for example from about 0.1 wt% to about 0.5 wt%, for example 0.5 wt% or less, such as 0.3 wt% or less, for example 0.1 wt% or less, for example 0 wt%.

[0132] The compounds of the present disclosure include tautomers, geometric isomers, or stereoisomers of the compounds. Esters, oximes, oniums, hydrates, solvates, and N-oxide forms of the compounds are also encompassed by the present disclosure. The present disclosure contemplates any and all compounds, including cis- and trans-geometric isomers (Z- and E-geometric isomers), R- and S-enantiomers, diastereomers, d-isomers, l-isomers, atropisomers, epimers, conformers, rotamers, mixtures of isomers, and racemates of the compounds.

[0133] The description of various aspects of the present disclosure is presented for illustrative purposes and is not intended to be exhaustive or limited to the disclosed aspects. Numerous modifications and variations will be apparent to those skilled in the art without departing from the scope and spirit of the described aspects. The terms used in this specification are selected to best explain the principles, practical applications or technical improvements of the aspects with respect to the technology found in the market, or to enable other skilled in the art to understand the aspects disclosed herein.

Claims

1. Organosilanes; Metal alkoxides; Acid stabilizers; and Organic solvents having a water content of 1 wt. % or less based on the total weight of the sol-gel; Metal alkoxides include zirconium(IV) tetramethoxide, zirconium(IV) tetraethoxide, zirconium(IV) tetra-n-propoxide, zirconium(IV) tetra-isopropoxide, zirconium(IV) tetra-n-butoxide, zirconium(IV) tetra-isobutoxide, zirconium(IV) tetra-n-pentoxide, zirconium(IV) tetra-isopentoxide, zirconium(IV) tetra-n-hexoxide, zirconium(IV) zirconium(IV) tetra-isohexoxide, zirconium(IV) tetra-n-heptoxide, zirconium(IV) tetra-isoheptoxide, zirconium(IV) tetra-n-octoxide, zirconium(IV) tetra-n-isooctoxide, zirconium(IV) tetra-n-nonaoxide, zirconium(IV) tetra-n-isononoxide, zirconium(IV) tetra-n-decyloxide, zirconium(IV) tetra-n-isodecyloxide; The organosilane is 2-(3,4-epoxycyclohexyl)ethyltrimethoxysilane, 2-(3,4-epoxycyclohexyl)ethyltriethoxysilane, 3-Aminopropyltriethoxysilane, p-aminophenyltrimethoxysilane, p-aminophenyltriethoxysilane, allyltrimethoxysilane, n-(2-aminoethyl)-3-aminopropyltrimethoxysilane, 3-aminopropyltriethoxysilane, 3-aminopropyltrimethoxysilane, 3-mercaptopropyltrimethoxysilane, 3-mercaptopropyltriethoxysilane, 3-methacryloxypropylmethyldiethoxysilane, 3-methacryloxypropylmethyldimethoxysilane, 3-methacryloxypropyltrimethoxysilane one or more of 3-(trimethoxysilane), n-phenylaminopropyltrimethoxysilane, vinylmethyldiethoxysilane, vinyltriethoxysilane, vinyltrimethoxysilane, bis[3-(triethoxysilyl)propyl]disulfide, bis[3-(trimethoxysilyl)propyl]disulfide, bis[3-(triethoxysilyl)propyl]trisulfide, bis[3-(trimethoxysilyl)propyl]trisulfide, bis[3-(triethoxysilyl)propyl]tetrasulfide, or bis[3-(trimethoxysilyl)propyl]tetrasulfide; or formula: (In the above formula, R ２ , R ３ and R ４ Each of the groups is independently a linear or branched C １－２０ alkyl, R １ is alkylene, cycloalkylene, ether or arylene. is an organosilane represented by Sol-gel.

2. the sol-gel has a water content of 0.1% to 1% by weight relative to the total weight of the sol-gel; or 2. The sol-gel of claim 1, wherein the sol-gel has a water content of 0.5% by weight or less, based on the total weight of the sol-gel.

3. the organic solvent is one or more of alcohol, ethylene glycol, propylene glycol, polyethylene glycol, polypropylene glycol, ether, tetrahydrofuran, N-methyl-2-pyrrolidone, and dimethylsulfoxide; or and / or the organic solvent is an alcohol, which is ethanol, n-propanol, isopropanol, 1-butanol, 2-butanol, 1-pentanol, 2-pentanol, 3-pentanol, 1-hexanol, 2-hexanol or 3-hexanol; and / or The sol-gel of claim 1 or 2, wherein the organic solvent is anhydrous.

4. Organosilanes include 3-aminopropyltriethoxysilane, 3-glycidoxypropyltriethoxysilane, p-aminophenyltrimethoxysilane, p-aminophenyltriethoxysilane, allyltrimethoxysilane, n-(2-aminoethyl)-3-aminopropyltrimethoxysilane, 3-aminopropyltriethoxysilane, 3-aminopropyltrimethoxysilane, 3-glycidoxypropyldiisopropylethoxysilane, (3-glycidoxypropyl)methyldiethoxysilane, 3-glycidoxypropyltrimethoxysilane, 3-mercaptopropyltrimethoxysilane, 3-mercaptopropyltriethoxysilane, 3-methacryloxypropylmethyldiethoxysilane, 3-methacryloxypropyltrimethoxysilane, 3-methacryloxypropyltriethoxy ...

4. The sol-gel of any one of claims 1 to 3, which is one or more of acryloxypropylmethyldimethoxysilane, 3-methacryloxypropyltrimethoxysilane, n-phenylaminopropyltrimethoxysilane, vinylmethyldiethoxysilane, vinyltriethoxysilane, vinyltrimethoxysilane, bis[3-(triethoxysilyl)propyl]disulfide, bis[3-(trimethoxysilyl)propyl]disulfide, bis[3-(triethoxysilyl)propyl]trisulfide, bis[3-(trimethoxysilyl)propyl]trisulfide, bis[3-(triethoxysilyl)propyl]tetrasulfide or bis[3-(trimethoxysilyl)propyl]tetrasulfide.

5. The organosilane has the formula: (In the above formula, R ２ , R ３ and R ４ Each of the groups is independently a linear or branched C １－２０ alkyl, R １ is alkylene, cycloalkylene, ether or arylene. The sol-gel according to any one of claims 1 to 3, represented by:

6. R ２ , R ３ and R ４ each of is methyl, ethyl, propyl, butyl, pentyl, hexyl, heptyl, octyl, nonyl, decyl, undecyl, dodecyl, tridecyl, tetradecyl, pentadecyl, hexadecyl, heptadecyl, octadecyl, nonadecyl, or icosanyl; and R １ is methylene, ethylene, propylene, butylene, pentylene, hexylene, heptylene, octylene, nonylene, decylene, undecylene, dodecylene, tridecylene, tetradecylene, pentadecylene, hexadecylene, heptadecylene, octadecylene, nonadecylene or icosanylene, or R １ Polyethylene glycol ether, polypropylene glycol ether, C １－２０ an ether which is an alkyl ether, an aryl ether or a cycloalkyl ether; Optionally, R １ but, (wherein n is a positive integer) The sol-gel of claim 5, which is one of:

7. The organosilane is The sol-gel according to any one of claims 1 to 6, wherein

8. 10. A method of forming the sol-gel of claim 1, comprising: mixing a metal alkoxide, an acid stabilizer, and an organic solvent to form a first mixture having a water content of 1 wt. % or less based on a total weight of the first mixture; and mixing an organosilane with the first mixture to form a second mixture having a water content of 1 wt. % or less based on the total weight of the second mixture; Including, Metal alkoxides include zirconium(IV) tetramethoxide, zirconium(IV) tetraethoxide, zirconium(IV) tetra-n-propoxide, zirconium(IV) tetra-isopropoxide, zirconium(IV) tetra-n-butoxide, zirconium(IV) tetra-isobutoxide, zirconium(IV) tetra-n-pentoxide, zirconium(IV) tetra-isopentoxide, zirconium(IV) tetra-n-hexoxide, zirconium(IV) zirconium(IV) tetra-isohexoxide, zirconium(IV) tetra-n-heptoxide, zirconium(IV) tetra-isoheptoxide, zirconium(IV) tetra-n-octoxide, zirconium(IV) tetra-n-isooctoxide, zirconium(IV) tetra-n-nonaoxide, zirconium(IV) tetra-n-isononoxide, zirconium(IV) tetra-n-decyloxide, zirconium(IV) tetra-n-isodecyloxide; The organosilane is 2-(3,4-epoxycyclohexyl)ethyltrimethoxysilane, 2-(3,4-epoxycyclohexyl)ethyltriethoxysilane, 3-Aminopropyltriethoxysilane, p-aminophenyltrimethoxysilane, p-aminophenyltriethoxysilane, allyltrimethoxysilane, n-(2-aminoethyl)-3-aminopropyltrimethoxysilane, 3-aminopropyltriethoxysilane, 3-aminopropyltrimethoxysilane, 3-mercaptopropyltrimethoxysilane, 3-mercaptopropyltriethoxysilane, 3-methacryloxypropylmethyldiethoxysilane, 3-methacryloxypropylmethyldimethoxysilane, 3-methacryloxypropyltrimethoxysilane one or more of 3-(trimethoxysilane), n-phenylaminopropyltrimethoxysilane, vinylmethyldiethoxysilane, vinyltriethoxysilane, vinyltrimethoxysilane, bis[3-(triethoxysilyl)propyl]disulfide, bis[3-(trimethoxysilyl)propyl]disulfide, bis[3-(triethoxysilyl)propyl]trisulfide, bis[3-(trimethoxysilyl)propyl]trisulfide, bis[3-(triethoxysilyl)propyl]tetrasulfide, or bis[3-(trimethoxysilyl)propyl]tetrasulfide; or formula: (In the above formula, R ２ , R ３ and R ４ Each of the groups is independently a linear or branched C １－２０ alkyl, R １ is alkylene, cycloalkylene, ether or arylene. The organosilane is represented by

9. incubating the second mixture at a temperature between 10°C and 100°C; and / or Curing the second mixture at a temperature between 10°C and 150°C. The method of claim 8 , further comprising:

10. depositing the first mixture or the second mixture onto a metal substrate; and / or Cleaning the metal substrate by degreasing, alkaline cleaning, chemical etching, chemical deoxidation or mechanical deoxidation of the metal surface prior to deposition; and / or Depositing a secondary layer on the sol-gel Including, Optionally, the metal substrate comprises aluminum, aluminum alloys, nickel, iron, iron alloys, steel, titanium, titanium alloys, copper, and copper alloys; 10. The method of claim 8 or 9, optionally wherein the metal substrate comprises steel.

11. Combining the metal alkoxide and the acid stabilizer is carried out by sequentially depositing the metal alkoxide onto the metal substrate and depositing the acid stabilizer onto the metal substrate; or The first mixture and the second mixture have a water content of 0.1% to 1% by weight, based on the total weight of the first mixture and the second mixture, respectively; or 11. The method according to any one of claims 8 to 10, wherein the first mixture and the second mixture have a water content of 0.5 wt. % or less, based on the total weight of the first mixture and the second mixture, respectively.

12. the organic solvent is one or more of alcohol, ethylene glycol, propylene glycol, polyethylene glycol, polypropylene glycol, ether, tetrahydrofuran, N-methyl-2-pyrrolidone, and dimethylsulfoxide; or the organic solvent is an alcohol, which is ethanol, n-propanol, isopropanol, 1-butanol, 2-butanol, 1-pentanol, 2-pentanol, 3-pentanol, 1-hexanol, 2-hexanol or 3-hexanol; and / or 12. The method of any one of claims 8 to 11, wherein the organic solvent is anhydrous.

13. the first mixture and the second mixture have an organic solvent content of 50% to 99% by weight, based on the total weight of the first mixture and the second mixture, respectively; or 13. The method according to any one of claims 8 to 12, wherein the first mixture and the second mixture have an organic solvent content of 90 wt. % to 95 wt. %, based on the total weight of the first mixture and the second mixture, respectively.

14. A vehicle component, Metal substrate and A sol-gel coating system comprising a sol-gel according to any one of claims 1 to 7 disposed on a metal substrate. A vehicle component including:

Images