This invention relates to an aqueous molecular hybrid organic/inorganic glass composition and polymeric hybrid organometalloglass coatings formed from the composition, with polymeric molecular hybrid nanocrystals optionally self-assembled in the composition and integrated in the coatings.
In one aspect, forming a polymerizable hybrid organometalloglass composition includes forming an aqueous, acidic colloid; processing the aqueous, acidic colloid to form an aqueous, alkaline colloid; processing the aqueous, alkaline colloid to remove chloride ions from the colloid and to form an aqueous, alkaline amorphous organo/siloxy/metal hydroxide colloid; combining a peroxide-based solution with the aqueous, alkaline amorphous organo/siloxy/metal hydroxide colloid to form a metal peroxide suspension; and processing the metal peroxide suspension to form a polymerizable hybrid organometalloglass composition. The aqueous, acidic colloid includes an organic monomer, a silicon-containing compound, and an organometallic compound. The alkaline colloid includes an amorphous metal hydroxide. The polymerizable hybrid organometalloglass composition may be applied to a substrate and polymerized to form a high molecular weight, covalently bonded polymeric hybrid organometalloglass coating on the substrate.
In another aspect, a polymerizable hybrid organometalloglass composition includes an aqueous suspension having siloxy groups, organic moieties, and amorphous metal hydroxide, and the suspension is capable of polymerizing to form a polymeric hybrid organometalloglass with a hardness between about 0.1 and about 7 GPa or between about 2.5 and about 7 GPa. In some implementations, the suspension further includes peroxy groups and/or nanoparticulates. Polymerizing can include forming a condensation product on a surface of a substrate.
In another aspect, a material includes a high molecular weight polymeric matrix. The matrix includes metal atoms, organic moieties, oxygen, and silicon, covalently bound together to form a coating with a hardness between about 0.1 and 7 GPa or between about 2.5 and about 7 GPa. In some implementations, the matrix further includes nanoparticulates.
Other implementations may include one or more of the following features. In some cases, forming the acidic colloid, processing the acidic colloid, forming the alkaline colloid, processing the alkaline colloid, forming the alkaline amorphous organo/siloxy/metal hydroxide colloid, forming the metal peroxide suspension, or any combination thereof can include heating the colloid, the suspension, or any precursor used in forming the colloid or the suspension. For example, forming the acidic colloid can include heating an acidic solution including an organic monomer, an organometallic compound, or a combination thereof. Heating can include heating at a temperature above room temperature at atmospheric pressure, above atmospheric pressure, or below atmospheric pressure. In some cases, heating includes autoclaving. Processing the alkaline colloid can include cooling the colloid, for example, at atmospheric pressure, above atmospheric pressure, or below atmospheric pressure. Cooling the colloid can include autoclaving the colloid. In some implementations, processing the metal peroxide suspension includes forming self-assembled nanocrystals in the suspension.
In some implementations, processing the aqueous, alkaline colloid to remove chloride ions from the colloid includes removing substantially all of the chloride ions from the colloid. For example, processing the aqueous, alkaline colloid to remove chloride ions from the colloid can include vacuum filtration and/or centrifuging the colloid and reconstituting the colloid repeatedly until a concentration of chloride ions in the supernatant is less than about 2 ppm or less than about 1 ppm. In some cases, reconstituting the colloid includes reconstituting the colloid in the presence of an ion exchange resin.
The polymerizable hybrid organometalloglass composition can be applied to a substrate and polymerized to form a polymeric hybrid organometalloglass coating on the substrate. In some cases, the substrate includes a multiplicity of nanoparticles. The polymerizable hybrid organometalloglass composition can be spray-dried on the particles (e.g., nanoparticles) and allowed to polymerize to form particles coated with polymeric hybrid organometalloglass. In certain cases, a polymerizable hybrid organometalloglass is spray-dried (e.g., at elevated temperatures) and then processed to form polymeric hybrid organometalloglass particles. The polymeric hybrid organometalloglass particles and the coated particles may be processed (e.g., ground to form a powder or nanopowder, classified, etc.) for use in a variety of applications. Polymerizing the hybrid organometalloglass composition can include allowing the composition to dry in air at room temperature and atmospheric pressure, or curing the composition under heat or pressure or in the presence of radiation, such as visible or ultraviolet radiation.
In some implementations, one or more additives may be combined with the acidic colloid, the alkaline colloid, the metal peroxide suspension, or the polymerizable hybrid organometalloglass composition. For example, forming or processing the acidic colloid or alkaline colloid may include combining an additive with the acidic colloid, the alkaline colloid, or one or more precursors thereof (e.g., to an acidic organic monomer solution). Forming the alkaline amorphous organo/siloxy/metal hydroxide colloid may include combining an additive with the alkaline amorphous organo/siloxy/metal hydroxide colloid or a precursor thereof. Forming or processing the metal peroxide suspension may include combining an additive with the metal peroxide suspension or a precursor thereof Forming or processing the polymerizable hybrid organometalloglass composition may include combining an additive with the polymerizable hybrid organometalloglass composition or a precursor thereof The additives can be selected to provide or enhance desired properties (e.g., self-cleaning, photocatalytic, anti-bacterial, hydrophobic/hydrophilic, conductivity, etc.) of the composition or coating. The additive can be, for example, an organic monomer, a silicon-containing compound, an organometallic compound, a wetting agent, a curing agent, a protein (e.g., enzyme), or a nanoparticulate. In one example, an additive includes one or more proteins (i.e., enzymes) selected from the group consisting of lysostaphin and lysozyme. The nanoparticulate can be, for example, a nanostructured carbon. Implementations include a polymeric hybrid organometalloglass coating, a substrate coated with a polymeric hybrid organometalloglass coating, a bulk material including a hybrid organometalloglass composition, and a device including a hybrid organometalloglass composition or a polymeric hybrid organometalloglass coating.
The polymerizable hybrid organometalloglass composition described herein may be tailored to yield coatings with selected chemical and physical properties combined with a desired hardness associated with the glass-like nature of the composition. A thickness of the coating may be determined by factors including composition and application process, and may range from monolayer thickness in the nanometer range up to any desired thickness formed by, for example, multiple layers in a lamination process. In some cases, the polymerizable hybrid organometalloglass composition is combined with a substrate material to provide selected chemical and physical properties to the bulk substrate material.
Referring to
Steps 102-110 of procedure 100 are described in more detail in
In
Referring to
The water-soluble organic compound may be an alkane (RH), alkene (R2C═CR2), alkyne (RC═CR), alcohol (ROH), aldehyde (RCHO), carboxamide, (RCONR2), amine (e.g., primary amine (RNH2), secondary amine (R2NH), tertiary amine (R3N)), quaternary ammonium ion (R4N+), azo compound (diimide) (RN2R), carbonate ester (ROCOOR), carboxylate (RCOO−), carboxylic acid (RCOOH), cyanate (ROCN), thiocyanate (RSCN), ether (ROR), ester (RCOOR), imine (e.g., primary ketimine (RC(═NH)R), secondary ketimine (RC(═NR)R), primary aldimine (RC(═NH)H), secondary aldimine (RC(═NR)H)), isocyanide (RNC), isocyanate (RNCO), isothiocyanate (RNCS), ketone (RCOR), nitro compound (RNO2), benzene derivative (RC6H5), phosphine compound (R3P), phosphodiester phosphate (HOPO(OR)2), phosphonic acid (RP(═O)(OH)2), phosphate (ROP(═O)(OH)2), pyridine derivative (RC5H4N, sulfide (RSR), sulfone (RSO2R), sulfonic acid (RSO3H), sulfoxide, sulfinyl (RSOR), and thiol sulfhydryl (RSH), where each R is independently an organic moiety that may include one or more of the same or different functional groups, such as hydroxyl groups or halogens (e.g., chlorine). Examples of the water-soluble organic monomer includes pentaerythritol, dimethylol propionic acid, neopentylglycol, and 2,2, bis (hydroxymethyl)-propionic acid.
Acids used in step 202 may include mineral acids such as hydrogen halides (HCl, HBr, HI), halogen oxoacids, hypochloric acid, chloric acid, perchloric acid, periodic acid and corresponding compounds of bromine and iodine, sulfuric acid (H2SO4), fluorosulfuric acid, nitric acid (HNO3), phosphoric acid (H3PO4), fluoroantimonic acid (HSbF6), fluoroboric acid (HBF4), hexafluorophosphoric acid (HPF6), chromic acid (H2CrO4), sulfonic acids (e.g., methanesulfonic acid (mesylic acid, MeSO3H), ethanesulfonic acid (esylic acid, EtSO3H), benzensulfonic acid (besylic acid, PhSO3H), p-toluenesulfonic acid (tosylic acid, CH3C6H4SO3H), trifluoromethanesulfonic acid (triflic acid, CF3SO3H)), carboxylic acids (e.g., acetic acid CH3COOH, glacial acetic acid, citric acid (3-hydroxypentanedioic acid), formic acid (methanoic acid, HCOOH), gluconic acid (C6H12O7 and HOCH2(CHOH)4COOH, one of the 16 stereoisomers of 2,3,4,5,6-pentahydroxyhexanoic acid), lactic acid (2-hydroxypropanoic acid, C3H6O3), oxalic acid (C2O2(OH)2 or HOOCCOOH), tartaric acid (2,3-dihydroxysuccinic acid), vinylogous carboxylic acids such as ascorbic acid), and Meldrum's acid (2,2-dimethyl-1,3-dioxane-4,6-dione). The molarity of the acid can be selected from a range of about 5 M to about 10 M. The organic monomer can be combined with the acid in an amount from about 0.01 to about 50% by weight of the acid. In an example, the organic monomer is added in an amount of about 5% by weight of the acid. The pH of the aqueous organic monomer solution may be less than 1. In some cases, step 202 includes autoclaving the organic monomer solution at increased or reduced pressures.
In step 204, the organic monomer solution is combined with a base. Examples of bases that can be used during neutralization and alklalinization include hydroxides such as NH4OH, KOH, Ba(OH)2, CsOH, NaOH, Sr(OH)2, Ca(OH)2, LiOH, RbOH, Mg(OH)2, and Al(OH)3, or a combination thereof. Non-hydroxide bases, such as NaHCO3 and CaCO3, may also be used. The base can be added in the form of a solid (e.g., in an amount between about 0.01 and about 25% by weight of the organic monomer solution) or in the form of a liquid (e.g., a solution). After addition of the base, the solution may still be acidic.
In step 206, the organic monomer solution from step 204 is heated at a temperature up to about 500° C. For example, the solution can be heated at about 150° C. In some cases, the solution is heated for a length of time between about 2 hrs and about 8 hrs.
In step 208, one or more additives (e.g., silicon-containing monomers, organic monomers, curing agents, or any combination thereof) is combined with the heated organic monomer solution. The total weight of the additives may account for about 0.01 wt % to about 15 wt % of the mixture formed in step 208. In some cases, for example, the total weight of the additives combined with the organic monomer solution from step 206 is about 2.5 to about 5 wt % of the mixture formed in step 208.
The silicon-containing monomers or compounds added in step 208 may include, for example, alkoxysilanes such as tetramethoxysilane and tetraethoxysilane, dipodal silanes such as bis(trimethoxysilylpropyl)-amine, bis(triethoxysilyl)methane, silsesquioxanes, siloxane, disiloxane, polydimethylsiloxanes, disilylmethylene, disilylethylene, silphenylene, metal silanolates, silazanes (e.g., (RO)3Si—CH2CH2CH2X where X is F, Cl, C≡N, NH2, SH, hybrid acetate-alkene, or epoxide, and R is an organic moiety), and disilazanes. Suitable silanes may have substituents including one or more allyl, alkynl, phenyl, hydroxyl, phenoxy, and acetoxy groups, cyclic or heterocyclic groups (including, for example, trimers, tetramers, and pentamers), halogens, ketones, azides, and isocyanates. Suitable silazanes include, for example, 1,3-di-n-propyltetramethyldisilazane and 1,1,3,3-tetramethyldisilazane. Some suitable silicon-containing monomers, including bis(triethoxysilyl)methane, 1,1,3,3-tetramethyl-1,3-diethoxydisiloxane, tetraethoxysilane, hexachlorodisiloxane, and octachlorotrisiloxane, form low molecular weight cyclic ring compounds that are soluble in aqueous solution. Other suitable silicon-containing compounds include metal silanoates, such as beryllium aluminum silicate, lithium aluminum silicate, aluminum silicate, lithium trimethylsilanolate, bis(trimethylsilyl) telluride, trimethylsilyltrimethyl germanium.
The organic monomers added in step 208 may include monomers described with respect to step 202, for example 2-hydroxyethyl acrylate or any other water-soluble organic monomer. The curing agents added in step 208 may include, for example, silazanes, disilazanes, and other silicon-containing compounds such as, for example, tetrakis (trimethylsiloxy) titanium and/or zirconium compounds. Calcium hydroxide may also function as a curing agent.
In certain cases, one or more of the silicon-containing monomers may be combined with a peroxide-based solution before addition in step 208. The peroxide-based solution may include, for example, hydrogen peroxide, benzoyl peroxide, tert-butyl hydroperoxide, 3-chloroperoxybenzoic peroxide, di-tert-butyl peroxide, dicumyl peroxide, methylethyl ketone peroxide, [dioxybis(1-methylpropylidene)] bishydro-peroxide, (1-methylpropylidene)bishydroperoxide, peracetic acid, or any combination thereof. The peroxide-based solution may be about 35 to about 50% by weight of peroxide in aqueous solution. The amount of peroxide-based solution combined with the silicon-containing monomer may be, for example, from about 0.1% by weight of the silicon-containing monomer to about 200% by weight of the silicon-containing monomer.
In some embodiments, one or more additives may be may be combined with the solution formed in step 204 at room temperature, and then heated in step 210 (i.e., the order of steps 206 and 208 may be interchanged).
In step 210, the mixture formed in step 208 is heated to form an aqueous, acidic colloid. Heating may include, for example, refluxing the mixture. After refluxing begins, the mixture may be heated between about 150° C. and about 500° C. for a length of time between about 2 hrs and about 10 hrs. Heating may also include autoclaving under increased or reduced pressure. After heating, the mixture may be agitated. For example, the mixture may be agitated for a length of time between about 8 hrs and about 72 hrs after heating. During this time, the mixture may cool to room temperature.
In step 212, one or more organometallic compounds, one or more chloride salts, or any combination thereof, is added to the colloid formed in step 210. Organometallic compounds added in step 212 can include, for instance, metal alkoxides such as methoxides, ethoxides, methoxyethoxides, butoxides, isopropoxides, pentoxides, etc., as well as pentadionates, proprionates, acetates, hydroxides, hydrates, stearates, oxalates, sulfates, carbonates, and/or acetylacetonates, etc., of metals such as zinc, tungsten, titanium, tantalum, tin, molybdenum, magnesium, lithium, lanthanum, indium, hafnium, gallium, iron, copper, boron, bismuth, antimony, barium, zirconium, zinc, yttrium, vanadium, tin, silver, platinum, palladium, samarium, praseodymium, nickel, neodymium, manganese, magnesium, lithium, lanthanum, indium, holmium, hafnium, gallium, gadolinium, iron, europium, erbium, dysprosium, copper, cobalt, chromium, cesium, cerium, aluminum, barium, beryllium, cadmium, calcium, iridium, arsenic, germanium, gold, lutetium, niobium, potassium, rhenium, rhodium, rubidium, ruthenium, scandium, selenium, silicon, strontium, tellurium, terbium, thulium, thorium, ytterbium, and yttrium. An example of an organometallic compound is silver pentadionate.
Chloride salts added in step 212 may include tetrachloride salts such as, for example, SiCl4, TiCl4, GeCl4, VCl4, GaCl4, ZrCl4, SnCl4, TeCl4, HfCl4, ReCl4, IrCl4, PtCl4, or other chloride salts such as, for example, Na2PtCl6, CCl3CO2Na, Na2PdCl4, NaAuCl4, NaAlCl4, ClNaO3, MgCl2, AlCl3, POCl3, PCl5, PCl3, KCl, MgKCl3, LiCl.KCl, CaCl2, FeCl2, MnCl2, Co(ClO4)2, NiCl2, Cl2Cu, ZnCl2, GaCl3, SrCl2, YCl3, MoCl3, MoCl5, RuCl3, RhCl3, PdCl2, AsCl3, AgClO4, CdCl2, SbCl5, SbCl3, BaCl2, CsCl, LaCl3, CeCl3, PrCl3, SmCl3, GdCl3, TbCl3, HoCl3, ErCl3, TmCl3, YbCl3, LuCl3, WCl6, ReCl5, ReCl3, OsCl3, IrCl3, PtCl2, AuCl, AuCl3, Hg2Cl2, HgCl2, HgClO4, Hg(ClO4)2, TlCl3, PbCl2, BiCl3, GeCl3, HfCl2O, Al2Cl6, BiOCl, [Cr(H2O)4Cl2]Cl2.2H2O, CoCl, DyCl3.6H2O, EuCl2, EuCl3.6H2O, NH4AuCl4.xH2O, HAuCl4.xH2O, KAuCl4, NaAuCl4.xH2O, InCl3, (NH4)3IrCl6, K2IrCl6, MgCl2.6H2O, NdCl3, (NH4)2OsCl6, (NH4)2PdCl6, Pd(NH3)2Cl2, [Pd(NH3)]4Cl2.H2O, (NH4)2PtCl6, Pt(NH3)2Cl2, Pt(NH3)2Cl2, [Pt(NH3)4]Cl2.xH2O, [Pt(NH3)4][PtCl4], K2PtCl4, KClO4, K2ReCl6, (NH4)3RhCl6, [RhCl(CO)((C6H5)3P)2], [RhCl(C6H5)3P)3], [Rh(NH3)5Cl]Cl2, K3RhCl6, RbCl, RbClO4, (NH4)2RuCl6, [RuCl2 ((C6H5)3P)3], {Ru(NH3)6}Cl2, K2RuCl6, ScCl3.xH2O, AgCl, NaCl, TlCl, SnCl2, and additional water adducts thereof. The organometallic compound/chloride salt may be added in an amount in the range of about 0.1% by weight to about 20% by weight of the colloid formed in step 210.
In some cases, additives including fillers, pigments, metals, and nanoparticulates may be added in any one or more of steps 202-212. The nanoparticulates can include nanostructured carbon (e.g., single-, double, and multi-walled nanotubes, nanographite platelets, nanocrystalline diamond, ultradisperse diamond, nanographite platelets), nanocrystals, nanopowders, nanofibers, silica aerogels, carbon aerogels, glass flakes, quantum dots, proteins (e.g., enzymes), etc. In one example, an additive includes one or more proteins (i.e., enzymes) selected from the group consisting of lysostaphin and lysozyme. The nanoparticulates can be functionalized or non-functionalized, and of any suitable shape, dimension, or composition. Suitable functional groups include, for example, hydroxyl groups and halogens (e.g., chlorine).
Nanoparticles that can be added in steps 202-212 include, for example, nanoparticles of aluminum, aluminum nitride, aluminum oxide, antimony, antimony oxide, antimony tin oxide, barium titanate, beryllium, bismuth oxide, boron carbide, boron nitride, calcium carbonate, calcium chloride, calcium oxide, calcium phosphate, cobalt, cobalt oxide, copper, dysprosium, dysprosium oxide, erbium, erbium oxide, europium, europium oxide, gadolinium, gadolinium oxide, gold, hafnium oxide, holmium, indium, indium oxide, iridium, iron cobalt, iron, iron nickel, iron oxide, lanthanum, lanthanum oxide, lead oxide, lithium manganese oxide, lithium, lithium titanate, lithium vanadate, lutetium, magnesium, magnesium oxide, molybdenum, molybdenum oxide, neodymium, neodymium oxide, nickel, nickel oxide, nickel titanium, niobium, niobium oxide, palladium, platinum, praseodymium, praseodymium oxide, rhenium, ruthenium, samarium, samarium oxide, silicon carbide, silicon nanoparticles, silicon nanotubes, silicon nitride, silicon oxide, silver, strontium carbonate, strontium titanate, tantalum, tantalum oxide, terbium, terbium oxide, thulium, tin, tin oxide, titanium carbide, titanium, titanium nitride, titanium oxide, tungsten carbide, tungsten, tungsten oxide, vanadium oxide, ytterbium, yttria stabilized zirconia, yttrium, zinc oxide, zirconium, zirconium oxide, and any combination thereof.
In some cases, particles ranging in size from nanometers to microns, such as polycrystalline, single crystal, shaped charge microparticles, or a combination thereof, optionally coated with hybrid polymeric layers with or without self-assembled or dispersed nanoparticulates, can be added in steps 202-212. These particles include, for example, antimony selenide, antimony telluride, bismuth selenide, bismuth telluride, boron carbide, silicon carbide, tungsten carbide, gallium antimonide, gallium arsenide, gallium indium antimonide, gallium indium arsenide, gallium phosphide, gallium(II) telluride, gallium(III) telluride, germanium telluride, indium antimonide, indium arsenide, indium phosphides, indium phosphide arsenide, indium selenide, indium sulfide, indium telluride, silicon arsenide, silicon phosphides, tin arsenide, tin selenide, tin telluride, and zinc telluride.
The colloid resulting from step 212 may be heated in step 214. In some cases, the colloid is heated to a temperature in a range from about room temperature up to about 100° C. Heating may include autoclaving at increased or reduced pressures. For example, the colloid may be heated to a temperature between about 45° C. and about 60° C. in any one of steps 202-212 during the addition and mixed for up to about 48 hrs to yield the aqueous acidic organo/siloxy/metal chloride colloid of step 102. In some cases, mixing may continue after heating has been discontinued. In some cases, after heating for up to about 8 hours, the colloid may be brought to room temperature and mixed at room temperature. A pH of the colloid in step 214 may be less than 1. For example, a pH of the colloid in step 214 may be in a range between about 0.01 and about 0.5, or between about 0.2 and about 0.3.
Steps in
Referring to
In step 304, the solids content of the colloid may be increased by addition of one or more non-halo-substituted (e.g., non-chloro-substituted) silicon-containing monomers, one or more non-halo-substituted organic monomers, one or more non-halo-substituted curing agents, one or more non-halo-substituted metal-containing compounds, or any combination thereof, as described, for example, with respect to
Silicon-containing monomers and/or curing agents added to the colloid when the colloid has a pH in a range between about 0.2 and 0.3 form a soluble glass, as indicated by self-foaming under agitation. In some cases, step 304 includes successive addition of silicon-containing monomers and/or curing agents followed by pH adjustment, with a final addition of silicon-containing monomers and/or curing agents up to a pH of about 11. After the desired increase of the solids content, a pH of the colloid may be adjusted to fall in a range between about 11 and about 12. 5, or between about 11 and about 14.
Following the addition of solids and base in step 304, the colloid may be optionally processed in step 306. Processing in step 306 may include mixing, heating, equilibrating, or any combination thereof at a temperature between room temperature and about 500° C. for up to about 96 hrs. In some cases, heating occurs under pressure. In an example, the colloid may be heated up to about 150° C., and then agitated without heating for a length of time between about 8 hrs and about 72 hrs. During agitation, the colloid may cool to room temperature. As used herein, agitation includes any method of mixing or dispersion, including cavitation. In some cases, the solids content (e.g., the weight of the organo/siloxy/metal components) of the alkaline colloid in step 306 exceeds the solids content of the acidic colloid following step 214 by about 10% to about 200%.
In step 308, the colloid is processed to remove chloride ions from the colloid. This may be achieved with a variety of methods including, for example, vacuum filtration, decantation, centrifugation, fluidized bed ion-exchange, and other physical and chemical methods, to yield a substantially chloride-ion-free amorphous solid.
In step 310, the colloid is reconstituted from the amorphous solid to yield an aqueous, alkaline amorphous organo/siloxy/metal hydroxide colloid. The colloid may be reconstituted a number of times (e.g., up to about 10 times). Reconstitution may include mixing an aqueous solution with the amorphous solid in a weight ratio of aqueous solution to amorphous solid between about 2:1 and about 4:1. To facilitate removal of ions (e.g., halide ions, such as chloride ions) from the reconstituted colloids, the aqueous solution may be essentially free of ions (e.g., water used to form the aqueous solution may be deionized). The aqueous solution may be basic, such that the colloid remains alkaline following successive reconstitutions. In some cases, for example, the aqueous solution includes aqueous ammonium hydroxide. In an example, the aqueous solution includes about 2 wt % of ammonium hydroxide (e.g., about 2 M to about 9 M NH4OH). In some cases, the aqueous solution includes a base. In an example, the base is calcium hydroxide, and an amount of calcium hydroxide added to the aqueous solution is between about 0.001% and about 3.5% by weight of the aqueous solution.
After a second centrifugation, the reconstituted colloidal suspension, which may be cooled through refrigeration to a temperature between about 2° C. and about 5° C., undergoes a chemical reaction that results in self-foaming. Chloride ion concentration in the supernatant after a second centrifugation may be around 5,000 ppm.
Repeated centrifugation and reconstitution of the colloid reduces particle sizes of the amorphous solid. Centrifugation may also result in more effective removal of ions and a more homogeneous colloid than other methods, such as filtration and decantation. In an example, 750 mL of a colloid formed in step 304 is centrifuged at 4150 rpm between about 8 hrs and about 24 hrs at a temperature between the freezing point and up to and including the boiling point. In some cases, the colloid is cooled to about 4° C. during centrifugation and then allowed to equilibrate at room temperature. The resulting amorphous solid is separated, reconstituted, and then centrifuged again, for a total of up to 10 successive centrifugation steps. The centrifugation steps may be different lengths of time. In some cases, a first centrifugation step may be shorter than successive centrifugation steps. For example, a first centrifugation step may be about 8 hrs in length, and successive centrifugation steps may be about 24 hrs in length.
Successive centrifugation steps may result in a reduction of chloride ion concentration in the supernatant to less than about 1 ppm. Reduction of chloride ion concentration may also be enhanced through the use of an ion exchange resin in step 310. The ion exchange resin may be added in an amount between about 0.01 wt % and about 2 wt %, or between about 0.5 wt % and about 0.75 wt %. A pH of the colloid resulting from step 310 is at least about 8, or at least about 8.4.
Step 402 includes adjusting the solids content in the alkaline amorphous organo/siloxy/metal hydroxide colloid of step 310, which may be about 4 wt %. A ratio of hybrid organosiloxy to polymeric molecular hybrid nanocrystals formed in the colloid may be about 1:1. Adjusting the solids content can include decreasing the solids content (e.g., by addition of water). For example, an amount of water added may be about 10% to about 250% by weight of the colloid. In some cases, the solids content may be increased by adding non-halogen-containing organic monomers described with respect to
Step 404 includes combining a first peroxide-based solution and the alkaline amorphous organo/siloxy/metal hydroxide colloid of step 402 to form an organo/siloxy/metal peroxide suspension. The peroxide-based solution may include, for example, hydrogen peroxide, benzoyl peroxide, tert-butyl hydroperoxide, 3-chloroperoxybenzoic peroxide, di-tert-butyl peroxide, dicumyl peroxide, methylethyl ketone peroxide, [dioxybis(1-methylpropyl idene)] bishydroperoxide, (1-methyl-propylidene) bishydroperoxide, peracetic acid, or any combination thereof. The strength of the peroxide-based solution may be, for example, in a range from about 25% to about 50%. Before addition of the peroxide-based solution, the pH of the colloid may be in a range between about 6 and about 10.5. A temperature of the colloid may be in a range from about 1° C. to room temperature before addition of the peroxide-based solution. The peroxide-based solution may be added directly to the colloid, in an amount of about 0.1% to about 200% by weight of the colloid. Addition of the peroxide-based solution results in an exothermic reaction, and yields an organo/siloxy/metal peroxide suspension.
In step 406, the organo/siloxy/metal peroxide colloid suspension is allowed to equilibrate at room temperature. The pH of the equilibrated suspension may be in a range from about 4 to about 7.5, or near neutral. Stabilization and solubilization of the system results in a substantially clear, transparent suspension after equilibration at room temperature.
In some cases, two or more different organo/siloxy/metal peroxide suspensions may be prepared through step 404 and combined in step 406. This option is suitable, for example, when some reactants (e.g., certain metal salts and silane or siloxy species), exhibit deleterious results when mixed together. In an example, a first, non-silicon-containing suspension is prepared through step 404 and a second, silicon-containing suspension is prepared through step 404. The first and second suspensions are then combined before, after, or during equilibration at room temperature in step 406.
Referring to
Step 410 includes heating the suspension. The suspension may be heated to a temperature between about room temperature and about 500° C. (e.g., to about 150° C.). The suspension may be heated for about 1 hr to about 10 hrs. Heating in step 410 occurs without substantial agglomeration of particles in the suspension. In some cases, heating in step 410 includes refluxing or autoclaving. Autoclaving may include pressures at, above, or below atmospheric pressure.
Step 412 includes increasing the solids content of the metal peroxide suspension. The solids content of the suspension may be increased by addition of one or more non-chloro-substituted silicon-containing monomers, one or more non-chloro-substituted organic monomers (e.g., as described with respect to step 202), one or more non-chloro-substituted curing agents, one or more non-chloro-substituted metal-containing (e.g., organometallic) compounds, or any combination thereof, as described with respect to
Step 414 includes optionally adjusting (e.g., increasing or decreasing) the pH of the suspension. For example, a basic solution may be added to the suspension. In some cases, the basic solution includes ammonium hydroxide with a concentration between about 0.1 M and about 9 M. The basic solution may be added in an amount from about 0.1% to about 10% by weight of the suspension. In some cases, the suspension is heated in step 414.
As indicated in
In step 416, the suspension resulting from step 414 (or step 410, if steps 412 and 414 are not performed) is heated. Heating may include refluxing under pressure or autoclaving under increased or reduced pressure. Nanocrystal growth occurs during this heating process. Heating under pressure yields a clear, polymerizable organo/siloxy composition with self-assembled nanocrystals distributed throughout the composition. Step 416 may include heating at a temperature up to about 500° C. (e.g., to about 150° C.). The suspension may be heated for a length of time between about 2 hrs and about 20 hrs. The suspension may be heated at a pressure of about 0 psi to about 10 psi to about 100 psi above atmospheric pressure. In some cases, the suspension may be heated at a pressure up to about 75,000 psi. The resulting suspension may have a pH in a range between about 5 and 10.5. In some cases, an organometallic compound is added to the suspension together with the addition of a base to adjust the pH of the suspension. For example, the additive may be combined with the suspension after the suspension is refluxed for a length of time up to about 0.5 hrs, about 4 hrs, about 12 hrs, about 20 hrs, or about 24 hrs.
In step 418, the composition may be adjusted to suit the intended application. For example, a pH of the suspension may be adjusted based on the substrate to which the composition is to be applied. Optionally, one or more organic monomers, one or more silicon containing monomers, powders, curing agents, wetting agents, or any combination thereof (e.g., as described with respect to
Referring to
In step 504, a substantially continuous layer of the composition is formed on the substrate. A coating can be used as a sealant to protect a substrate from the environment, or on top of a sealant as an additional coating. Examples of that can be used with the compositions described herein include porous and non-porous, transparent, translucent, and opaque substrates, such as metals, metal alloys, glass (e.g., optical glass and industrial glass), polymeric materials (e.g., thermoplastics, thermosets), textiles, building materials (e.g., concrete and vinyl), ceramics, pigments, fillers, fiber materials, electronics, carbon, graphite, ceramics, thermoplastics, thermosets, resin materials, inorganic materials, organic materials, rubber, wood, paper, waste, skin, hair, and in particular, substrates and surfaces such as surgical steel, untreated steel in medical devices, fiberglass, cement, and fiber optics.
In step 506, the composition is solidified to form a polymeric coating on the substrate. In some cases, solidifying the composition includes providing a polymerizable hybrid organometalloglass composition including an aqueous carrier and the condensation product of an organo/siloxy/nanocrystal composition, applying the composition to a surface of a substrate, and removing the aqueous carrier to form a polymeric hybrid organometalloglass coating on the surface of the substrate. The composition can be solidified under ambient conditions to form a substantially transparent polymeric coating. Ambient curing can be achieved, for example, by allowing the coating to dry in air at room temperature and atmospheric pressure. Under ambient conditions, the coating may be dry to the touch within a few hours (e.g., less than about 5 hrs), and hardened in about 7-10 days. A hardness of a hardened coating is at least about 0.1 GPa or at least 2.5 GPa (e.g., between the modulus of polycarbonate (0.48 GPa) and glass (7 GPa)) or between about 0.1 GPa and 7 GPa or between about 2.5 GPa and about 7 GPa. The composition can also be solidified by heating to form a polymeric coating on the substrate. In some cases, a polymerizable hybrid organometalloglass composition is spray-dried (e.g., at elevated temperatures) to form a polymeric hybrid organometalloglass powder. Visible or UV radiation may be used to facilitate polymerization of a hybrid organometalloglass composition. In some cases, a polymeric hybrid organometalloglass coating is treated (e.g., with electromagnetic radiation, heat, pressure, etc.) after curing to alter chemical and/or physical properties of the coating.
The coating formed in step 506 can be of monolayer thickness on the order of nanometers. In some implementations, a thickness of the coating is about 2-10 nm, about 3-8 nm, or about 4-6 nm. In other applications, a coating can have a thickness of about 10 nm to about 1 μm. For instance, a coating can have a thickness of about 10 nm to about 800 nm, about 100 nm to about 600 nm, or about 200 nm to about 500 nm. These coatings are continuous, covalently bonded, cross-linked, cured polymeric films, with no visible presence of agglomerated, non-continuous particles. In some implementations, a viscosity of a composition formed in step 418 is adjusted to form a thicker layer or coating, for instance, on the order of microns or thicker. Repeated application of one or more compositions can result in a coating of a desired thickness and with a desired number of layers (e.g., laminates) with the same or different functionality. In one example, a composition formed in step 418 is used as an intermediate layer between a substrate and a coating or between two layers on a substrate. The intermediate layer may serve as an adhesion layer to provide intercoat adhesion properties.
The organo-siloxy peroxy-metal-hydroxy nanocrystalline or polymeric hybrid organometalloglass coatings described herein respond to heat as an organic glass polymer and do not powder up and loose adhesion, but rather maintain clarity and film forming characteristics at temperatures up to, for example, 1000° C. These coatings can be boiled in water for up to an hour and still retain their adhesion and hardness.
The polymeric coating is both organic and inorganic in nature, and can have both hydrophilic and hydrophobic character. That is, the hybrid nanocrystals in the coating provide hydrophilic character, while the polymerized organo/siloxy network provides hydrophobic character. In some cases, the dual nature of this coating allows for a photoactive response in a portion of the coating near the surface (e.g., within one to a few nanometers of the surface), rather than throughout the entire depth of the coating. The hydrophobic nature of the polymerized organo/siloxy network inhibits water from infiltrating the entire depth of the coating, and thus reduces retention of foreign matter (e.g., dirt) in the coating and allows water to sheet off the surface. In some cases, based on additives included in the process shown in
Implementations of the process and chemistry illustrated in
In some implementations, the amorphous organo/siloxy/metal hydroxide colloidal suspension composition formed in step 402 is applied directly to a surface to form a coating on the surface, as depicted by steps 504 and 506. In other implementations, the amorphous organo/siloxy/metal hydroxide colloidal suspension composition formed in step 402 can be stored at room temperature for later use, dried to form a powder, vaporized to form a vapor, or applied to a surface, as depicted in step 504, dehydrated (for instance, spray dried) and collected as a powder to be used in nanopowder or nanocomposite powder form.
In some implementations, clear polymerizable organo/siloxy/nanocrystal compositions of 0.005% to 10% stabilized solids dispersed in water can be dried and processed to form nanocomposite powder particulates less than about 100 nm in diameter. These nanopowders or nanocomposite powders can be combined with another hybrid organometalloglass composition (for example, in steps 202 to 212 and/or steps 304, 402, 412, or 418) or other dispersions to improve mechanical, physical, and/or chemical properties of, for example, thermosets, thermoplastic extrusions, organic pigment dispersions, etc. Organo/siloxy/nanocrystal composite powders can be bonded to particulate substrates that are not readily dispersed into the composition or into a organo/siloxy/nanocrystal vehicle system to facilitate dispersion of the particulate substrates. In some cases, organo/siloxy/nanocrystal composite powders are bonded to particles not readily dispersed in, for example, thermoset or thermoplastic systems, to facilitate dispersion of the particles in the systems.
Amorphous organo/siloxy/metal hydroxide colloids (e.g., from steps 302, 304, 310, and 402) and polymerizable organo/siloxy/nanocrystal compositions (e.g., from steps 406, 416, and 502) may be used as coatings, sealants, supercritical fluids, heterogeneous or homogeneous dispersions, and/or powders. The compositions may be applied on, integrated in, or bound to a substrate. In some cases, these compositions may be homogenously or heterogeneously dispersed in liquids. In certain cases, the supercritical fluid compositions may be dispersed in other supercritical fluid compositions.
Substrates can be treated with selected hybrid organometalloglass compositions to enhance or impart catalytic, photocatalytic, self-cleaning, anti-microbial, anti-viral, anti-fungal, anti-corrosive, anti-fouling, semi-conductive, conductive, insulative, electromagnetic, transparent, optical, emissive, flame retardant, piezoelectric properties, refractory properties, abrasion resistance, or any combination thereof, to the substrate. The hydrophobic siloxy nanothin coatings described herein can be used to inhibit the contamination of polymeric, metallic, and cementitious substrates with microbial and viral infusions through the glassy surface. These coatings inhibit exposure of a coated substrate to oxidizing agents, and therefore inhibit subsequent degradation of the coated polymeric substrates.
Composition and thickness of a hybrid organometalloglass coating can be selected to achieve suitable values for properties such as insulating and dielectric properties (high and low dielectric constant), anti-static properties, infrared absorbance, selected (e.g., low or high) coefficients of friction, conductivity, refractive index, transparency, and reactivity. These coatings can be used in applications including thermoset-thermoplastic reinforcement, pigment dispersion, hydrogen storage, electrochemical and superconducting applications, preparation of light-sensitive photographic materials, and absorption of UV radiation.
Coatings formed from the compositions described herein can be instrumental in air/water remediation applications, bio-medical applications, electrical applications, and surface studies. Another use includes coatings suitable for controlling or containing radioactive contamination by providing a neutron absorbing material to a radioactive contamination site. Compositions used herein can also be used to form clear, electrically conductive films that can be used in field effect transistors, and electrodes. Solidified matrix materials described herein can be used as high-k dielectric gate material, capacitors, high thermal conductivity coatings, coatings transparent to infrared radiation, coatings that exhibit light-emitting and conductive properties, films with catalytic and/or photoreducing properties, powders or films with fire-retardant properties, as dielectrics in film capacitors and as gate insulators in LSI circuits requiring low leakage voltage characteristics, opacifying agents, powders with anti-reflective and/or interference properties, high-k films, and heat and thermal shock resistance enhancers. These films are also useful in electronic ceramics, thermistors, varistors, cermets, resistance heating elements, ceramic glazes, enamels, pigments, magnetic devices, ceramic capacitors, glazes, and colored glass, barriers for the penetration of corrosive elements and ultraviolet light, cements, fertilizers, and gas-scrubbing applications
Polymeric hybrid organometalloglass compositions described herein may be used in devices such as dye-sensitized solar cells, super capacitor thin films, electrical devices, optics, electro-optics, acousto-optics, laser optics, opto-electronic devices, gas-sensing devices, catalytic devices, electrochemical and superconducting devices, ceramics, capacitors, thin-film capacitors, hybrid circuits, semiconductor components, heterogeneous catalyst supports, microsensors (e.g., for MEMS technology), particle detectors, nanofilm composites for electronic devices, with a layer succession of metal-insulator-metal or metal-insulator-semiconductor used as memory cells in memory devices such as DRAMs (dynamic random access memory) or as passive components in high-frequency applications, electrochemical devices and displays, batteries, high refractory thin film crucible linings, resistive elements in integrated circuits, sputtering targets, conductive inks, display applications (e.g., flat panel, plasma, electroluminescent, electrochromic, field emission, etc.), and gas permeable inorganic membranes.
Compositions described herein may be used as additives for bricks, pigments, mortars, refractories, abrasives, adhesives, cement, slag adjustors, ceramics (including dielectric, ferroelectric, and conductive ceramics), aluminum chemicals, flame retardants, fillers, welding fluxes, adsorbents, adhesives, detergent zeolites, transducers (e.g., for loudspeakers and microphones), glasses, X-ray image intensifying screens, phosphors, raw materials for various fluorescent compounds, absorption material in atomic reactions, magnetic bubble material, screen-sensitivity increasing material, semiconductor electronics, piezoelectric resonators and transducers, and gate oxides.
Components such as silver may be incorporated into compositions described herein to improve biostatic efficacy of a coating. In some cases, nanothin siloxy layers may be used as nanothin glass barriers to limit exposure of an underlying substrate to hot water, oxygen plasma, ozone, peroxides, oxides, organic acids, and oxidizing flames. These lightweight, nanothin siloxy layers provide toughness, including stain and scratch resistance, as well as flexibility, and may be stored on rolls and molded packaging. The layers are substantially impermeable to gas and moisture, and demonstrate good adhesion to polymeric substrates.
The siloxy coatings described herein can be formulated to protect a variety of metal substrates from anodic and cathodic electrochemical transport, thus inhibiting the electrochemical circuit required for corrosion, including galvanic corrosion, concentration cell corrosion, oxygen concentration cell corrosion, filiform corrosion, metal ion concentration cell corrosion, active/passive corrosion cells, intergranular corrosion, exfoliation corrosion, and metallic mercury corrosion.
Further modifications and alternative embodiments of various aspects of the invention will be apparent to those skilled in the art in view of this description. Accordingly, this description is to be construed as illustrative only and is for the purpose of teaching those skilled in the art the general manner of carrying out the invention. It is to be understood that the forms of the invention shown and described herein are to be taken as examples of embodiments. Elements and materials may be substituted for those illustrated and described herein, parts and processes may be reversed, and certain features of the invention may be utilized independently, all as would be apparent to one skilled in the art after having the benefit of this description of the invention. Changes may be made in the elements described herein without departing from the spirit and scope of the invention as described in the following claims.
Filing Document | Filing Date | Country | Kind | 371c Date |
---|---|---|---|---|
PCT/US2010/059521 | 12/8/2010 | WO | 00 | 9/19/2012 |
Number | Date | Country | |
---|---|---|---|
61267752 | Dec 2009 | US |