WO2012145636A1

WO2012145636A1 - Aqueous stable compositions of alkali metal alkyl siliconates with arylsilanes, silsesquioxanes, or fluorinated alkylsilanes, and surface treatment methods using the compositions

Info

Publication number: WO2012145636A1
Application number: PCT/US2012/034466
Authority: WO
Inventors: Don Lee Kleyer; Donald T. Liles
Original assignee: Dow Corning Corporation
Priority date: 2011-04-20
Filing date: 2012-04-20
Publication date: 2012-10-26

Abstract

Water-dispersible aqueous compositions comprise at least one solvated alkali-metal C₁-C₄ hydrocarbyl siliconate and at least one solvated organosilicon component derived from an organosilicon compound. In example compositions, the organosilicon compound may comprise at least one silane, at least one phenylsilsesquioxane resin, or a mixture of at least one silane and at least one phenylsilsesquioxane resin. The organosilicon compound may comprise at least one hydrophobic group such as a phenyl group, an organic group with a carbon chain having more than three carbon atoms, or at least one fluoroalkyl group. Methods for forming the water-dispersible compositions comprise solvating the organosilicon compound in an aqueous solution containing at least one alkali-metal C₁-C₄hydrocarbyl siliconate. Further methods are disclosed for treating surfaces of substrates such as brick, masonry, concrete, and wood with the aqueous compositions to render the substrate surfaces hydrophobic and resistant to water and optionally oleophobic and resistant to oil.

Description

AQUEOUS STABLE COMPOSITIONS OF ALKALI METAL ALKYL SILICONATES WITH ARYLSILANES, SILSESQUIOXANES, OR FLUORINATED ALKYLSILANES, AND SURFACE-TREATMENT METHODS USING THE

COMPOSITIONS

TECHNICAL FIELD

[0001] The present invention relates in general to water-dispersible surface-treatment compositions and, more particularly, to water-dispersible surface-treatment compositions comprising at least one siliconate compound.

BACKGROUND

[0002] It is known that a limited number of alkali-metal alkyl siliconates can be prepared as aqueous compositions, typically by reacting chlorosilanes or alkoxysilanes with an aqueous alkali-metal hydroxide. For example, potassium methyl siliconate may be prepared by reacting MeSi(OMe)3 with KOH in water, followed by removal of methanol. This reaction effectively resembles dissolving the methyltrimethoxysilane in the aqueous potassium hydroxide. Even so, this dissolution-type chemistry is not effective when the starting materials contain fluoroalkyl groups or alkyl groups with greater than about three carbon atoms.

[0003] Potassium methyl siliconate is commercially available as an aqueous solution containing approximately 40% (w/w) of the siliconate. The commercially available potassium methyl siliconate may be diluted by the end user, typically to about 3% (w/w), and then may be applied to substrates such as masonry, brick, gypsum, or paper. Over time, the potassium methyl siliconate reacts with atmospheric C0₂ to form an alkali-metal carbonate and a silsesquioxane resin. The silsesquioxane resin renders the treated surfaces of the substrates hydrophobic.

[0004] For organosiliconate surface-treatment agents to render a surface hydrophobic, it may be desirable for the silsesquioxane resin formed after reaction of the siliconate with atmospheric C0₂ to comprise hydrophobic groups such as long alkyl chains or fluoroalkyl groups. Fluoroalkyl groups are particularly desirable in surface-treatment agents because they may render surfaces impervious to both water and oils. Desirable compounds in this regard may include, for example, butyl siliconates, hexyl siliconates, phenyl siliconates, tolyl siliconates, octyl siliconates, dodecyl siliconates, and fluoroalkyl siliconates. Yet, none of these compounds having the hydrophobic groups can be formed as aqueous solutions in the same manner as potassium methyl siliconate, i. e. , by simply dissolving a silane in potassium hydroxide, or by any other known route.

[0005] Thus, there remains a need for methods to form water-dispersible compositions containing alkali metal organosiliconates having hydrophobic groups, especially groups with more than three carbon atoms or with fluoroalkyl functionalities.

SUMMARY

[0006] According to embodiments disclosed herein, water-soluble or water-dispersible aqueous compositions are provided. The compositions comprise an alkali-metal C1-C4 hydrocarbyl siliconate and at least one organosilicon compound having fluoroalkyl groups, organic groups having more than 3 carbon atoms, or both, dissolved in the alkali-metal C1-C4 hydrocarbyl siliconate. Methods for preparation and use of the compositions are disclosed.

[0007] Embodiments disclosed herein are directed to water-dispersible aqueous compositions comprising a solvated alkali-metal C₁-C₄ hydrocarbyl siliconate and a solvated organosilicon component derived from an organosilicon compound. The organosilicon compound may be selected from the group consisting of (a) silanes having a formula

3 1

R _xSiZ 4-_x; (b) phenylsilsesquioxane resins having an average formula [PhSi0_3/2]_m[QSi0_3/2]„;

3 1 1

and (c) mixtures of (a) and (b). In the formula R _xSiZ ₄-_x, each Z is selected from the group

2 2 3 consisting of -OR , -CI, and -OH; each R is a Ci-C₄ hydrocarbyl; each R is selected from the group consisting of Ci-Cs hydrocarbyl, C3-C8 fluorohydrocarbyl, phenyl, tolyl, and R⁴, such that at least one group R in the organosilicon compound is Ci-Cs hydrocarbyl, C3-C8 fluorohydrocarbyl, phenyl, tolyl, or R⁴; R⁴ is -R⁵-0-(CH₂)r_f-R⁶, where <i is 1 or 2 ; R⁵ is a C3 linear alkylene or a C₄-C₅ branched alkylene; R⁶ is a Ci-C₆ perfluoroalkyl; and x is 1, 2, or 3. In the formula [PhSi03/₂]_m[QSi03/₂]«, each Q is a Ci-C₄ hydrocarbyl; m is from 0.5 to 1; n is from 0 to 0.5; and m + n = 1.

[0008] Further embodiments disclosed herein are directed to methods for forming water- dispersible aqueous compositions. The methods for forming the water-dispersible aqueous compositions may comprise adding an organosilicon compound to an aqueous solution containing a solvated alkali-metal Ci-C₄ hydrocarbyl siliconate to form a reaction mixture. The reaction mixture then may be heated, manipulated, or both, to completely solvate the organosilicon compound in the reaction mixture.

[0009] Still further embodiments disclosed herein are directed to methods for treating a substrate surface of a substrate with at least one water-dispersible aqueous composition. The methods may comprise applying a coating of a water-dispersible aqueous composition, according to one or more embodiments disclosed herein, having a total-solids content of from 0.1 wt.% to 45 wt.%. The coating then is exposed to atmospheric carbon dioxide, such that a cured, hydrophobic, waterproof, and optionally oil-proof layer forms within the treated substrate through a reaction of the water-dispersible aqueous composition with the atmospheric carbon dioxide.

[0010] These and other features, aspects, and advantages of the present invention will become better understood with reference to the following description and appended claims.

DETAILED DESCRIPTION

[0011] Features and advantages of the invention will now be described with occasional reference to specific embodiments. However, the invention may be embodied in different forms and should not be construed as limited to the embodiments set forth herein. Rather, these embodiments are provided so that this disclosure will be thorough and complete and will fully convey the scope of the invention to those skilled in the art.

[0012] Unless otherwise defined, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art to which the invention belongs. The terminology used in the description herein is for describing particular embodiments only and is not intended to be limiting. As used in the specification and appended claims, the singular forms "a," "an," and "the" are intended to include the plural forms as well, unless the context clearly indicates otherwise.

[0013] As used in the specification and appended claims, the term "each X is selected from the group consisting of A, B, and C," is equivalent to "each X is independently selected from A, B, and C." Either term is intended to mean that a plurality of groups X on the same molecule, on a plurality of molecules within a composition, or both, as the context would indicate, can be all the same as each other, can be all different from one another, or can comprise any conceivable mixture of A, B, and C, unless the context clearly indicates that any of these options are excluded.

[0014] As used in the specification and appended claims, the term "each X is a Y," where Y represents a class having more than one member, is equivalent to the phrase "each X is independently selected from the group consisting of all members of the class Y," unless the context clearly indicates otherwise.

[0015] Unless otherwise indicated, all numbers expressing quantities of ingredients, properties such as molecular weight, reaction conditions, and so forth as used in the specification and claims are to be understood as being modified in all instances by the term "about." Accordingly, unless otherwise indicated, the numerical properties set forth in the specification and claims are approximations that may vary depending on the desired properties sought to be obtained in embodiments of the present invention. Notwithstanding that the numerical ranges and parameters setting forth the broad scope of the invention are approximations, the numerical values set forth in the specific examples are reported as precisely as possible. One of ordinary skill in the art will understand that any numerical values inherently contain certain errors attributable to the measurement techniques used to ascertain the values.

[0016] As used herein, the term "hydrocarbyl" refers to a monovalent radical formed by removing any one hydrogen from a hydrocarbon molecule, where a "hydrocarbon molecule" is any molecule consisting of hydrogen atoms and carbon atoms. Except where defined otherwise, the term "hydrocarbyl" encompasses linear groups, branched groups, cyclic groups, and combinations thereof, wherein any two neighboring carbon atoms may be joined by a single bond, a double bond, or a triple bond. As used herein, the term "C_x to C_y hydrocarbyl," where x and y are integers, refers to a hydrocarbyl having from x to y total carbon atoms and a sufficient number of hydrogen atoms to maintain the monovalency of the hydrocarbyl.

[0017] As used herein, the term "halohydrocarbyl" refers to a monovalent radical formed by removing any one hydrogen from a halohydrocarbon molecule. A "halohydro carbon molecule" is a molecule that results from replacing one or more hydrogen atoms of a hydrocarbon molecule with an equal number of halogen atoms. Unless otherwise noted, each halogen atom is independently selected from the group consisting of fluorine, chlorine, bromine, and iodine. Subsets of halohydrocarbyls include, for example,

"fluorohydrocarbyls" consisting of hydrogen atoms, carbon atoms, and fluorine atoms;

"chlorohydrocarbyls" consisting of hydrogen atoms, carbon atoms, and chlorine atoms; and "chloro fluorohydrocarbyls" consisting of hydrogen atoms, carbon atoms, chlorine atoms, and fluorine atoms.

[0018] As used herein, the term "hydrocarbylene" refers to a divalent radical formed by removing any two hydrogen atoms from a hydrocarbon. The two hydrogen atoms may have been removed from the same carbon atom or from two different carbon atoms. The term "hydrocarbylene" encompasses linear groups, branched groups, cyclic groups, and combinations thereof, wherein neighboring carbon atoms may be joined by a single bond, a double bond, or a triple bond. Thus, "hydrocarbylene" encompasses both saturated hydrocarbylenes and unsaturated hydrocarbylenes. As used herein, the term "C_x to C_y hydrocarbylene," where x and y are integers, refers to a hydrocarbyl ene having from x to y total carbon atoms and a sufficient number of hydrogen atoms to maintain the divalency of the hydrocarbylene.

[0019] Alkali-metal organosiliconates are compounds containing an organosiliconate anion charge-balanced by one or more cations of an alkali metal such as lithium, sodium, potassium, rubidium, or cesium. As used herein, the term "organosiliconate" shall be construed according to the broadest definition understood by persons of ordinary skill in the relevant art and shall not be limited by any theory as to any precise structure of the anion inferred by characterization methods such as NMR.

[0020] Generally, the precise structure of siliconate anions in aqueous solution may be complex. In a simplified form siliconate anions may be represented by the general formula RSi(OH)_a(0 where R is a monovalent organic group and a + b = 3. The general formula encompasses monomeric species such as RSi(OH)₂(CT) and RSi(OH)(CT)₂; and also oligomeric species such as, for example, R(OH)(0 )Si-0-Si(OH)(0 )R,

R(OH)(0 )Si-0-Si(0 )₂R, R(OH)₂Si-0-Si(OH)(0 )R,

R(OH)(0 )Si-0-Si(OH)R-0-Si(OH)(0 )R, R(OH)₂Si-0-Si(0 )R-0-Si(OH)(0 )R, and analogous larger species, each species having a statistical distribution of OH groups and CT groups.

[0021] In an alkali-metal organosiliconate in solution, each group O of each

organosiliconate anionic species is charge-balanced by one or more alkali-metal cations M⁺, (each M⁺ = Li⁺, Na⁺, K⁺, Rb⁺, or Cs⁺). Typically, the ratio Si:M⁺ of silicon atoms (Si) to alkali-metal cations (M⁺) in an aqueous solution of an alkali-metal organosiliconate is greater than 1 or, alternatively, may range from about 0.8: 1 to about 1 : 1.5. For example, potassium methyl siliconate may have Si:M⁺ of about 1 : 1.2. Sodium methyl siliconate may have Si:M⁺ of about 1 : 1.1.

[0022] As used herein, the term "alkali-metal alkyl siliconate" refers to compounds or aqueous solutions in which siliconate anions of the above general formula and description are charge -balanced by alkali-metal cations selected from Li⁺, Na⁺, K⁺, Rb⁺, Cs⁺, and mixtures thereof, where R is an alkyl group. Likewise, the term "alkali-metal hydrocarbyl siliconate" shall refer to alkali-metal alkyl siliconates, in which R is a hydrocarbyl group, as defined above.

[0023] As used herein, the term "alkali-metal C₁-C₄ hydrocarbyl siliconate" shall refer to alkali-metal alkyl siliconates, in which R is a C₁-C₄ hydrocarbyl group. Non- limiting examples of C₁-C₄ hydrocarbyl groups include methyl, ethyl, /? -propyl, 1-methylethyl (isopropyl), n-butyl, 1-methylpropyl (isobutyl), 2-methylpropyl (sec-butyl), and 1,1-dimethylethyl (fert-butyl). In preferred embodiments, the C₁-C₄ hydrocarbyl is methyl or ethyl.

[0024] A water-dispersible aqueous composition according to various non-limiting embodiments comprises (I) a solvated alkali-metal C₁-C₄ hydrocarbyl siliconate, as defined above; and (II) a solvated organosilicon component. As used herein, the term "solvated" means that the alkali-metal C₁-C₄ hydrocarbyl siliconate and the organosilicon component are substantially solvated, preferably completely solvated, in the water-dispersible aqueous composition. As used herein, a component is "substantially solvated" when the component causes the water-dispersible composition to have a hazy appearance but does not form any visibly apparent agglomerates or precipitates within the water-dispersible aqueous composition. In this sense, a component is "completely solvated" when no solid form of the component is visibly detectable within the water-dispersible composition. Preferably, all components of the water-dispersible aqueous composition are completely solvated, such that the water-dispersible composition is a clear solution. As used herein, the term "water- dispersible" means that the composition may be diluted with an aqueous solvent, preferably water, more preferably deionized water, without resulting in precipitation of the solvated organosilicon component.

[0025] The solvated alkali-metal C₁-C₄ hydrocarbyl siliconate (I) is as defined above. The solvated alkali-metal C₁-C₄ hydrocarbyl siliconate (I) may be prepared by any known method or may be derived from any commercially available aqueous solution having an alkali-metal C₁-C₄ hydrocarbyl siliconate component. The organosilicon compound (II) is chosen from (a) a class of silanes defined below in detail, (b) a class of phenyl silsesquioxane resins defined below in detail, and (c) mixtures of (a) and (b). The solvated alkali-metal Ci- C₄ hydrocarbyl siliconate (I) may be prepared by any known method or may be derived from any commercially available aqueous solution having an alkali-metal C₁-C₄ hydrocarbyl siliconate component. The solvated organosilicon component (II) may be formed, for example, by dissolving a solid organosilicon compound, as described in detail below, in an aqueous solution of the solvated alkali-metal C₁-C₄ hydrocarbyl siliconate.

[0026] The water-dispersible composition comprises a solvated alkali-metal C₁-C4 hydrocarbyl siliconate, defined above in detail. The alkali metal of the siliconate may be chosen from the group consisting of lithium, sodium, potassium, rubidium, cesium, and mixtures thereof. In preferred embodiments, the alkali metal is chosen from the group consisting of lithium, sodium, potassium, and mixtures thereof. In especially preferred embodiments, the alkali metal is chosen from sodium, potassium, and mixtures thereof. In the alkali-metal C₁-C₄ hydrocarbyl siliconate, examples of the C₁-C₄ hydrocarbyl include, without limitation, methyl, ethyl, n-propyl, 1-methylethyl (isopropyl), n-butyl,

1-methylpropyl (isobutyl), 2-methylpropyl (sec-butyl), and 1,1 -dimethyl ethyl (tert-butyl). In preferred embodiments, the C₁-C₄ hydrocarbyl is methyl or ethyl. The solvated alkali-metal C₁-C₄ hydrocarbyl siliconate may comprise mixtures of one or more alkali-metal C₁-C₄ hydrocarbyl siliconates having different alkali-metal cations and/or different C₁-C₄ hydrocarbyl groups.

[0027] The water-dispersible composition further comprises a solvated organosilicon component (II) derived from an organosilicon compound. The organosilicon compound is selected from the group consisting of (a) silanes having a formula R 3 _xSiZ 1₄-_x; (b)

silsesquioxane resins having an average formula [PhSi03/2]_m[QSi03/2]«; and (c) mixtures of (a) and (b). The organosilicon component (II) may be formed, for example, by dissolving the organosilicon compound in an aqueous solution comprising the solvated alkali-metal C₁-C₄ hydrocarbyl siliconate, such that one or more substituents on the organosilicon compound are hydrolyzed. Without intent to be limited by theory, it is believed that solvated organosilicon compounds derived from silanes, for example, comprise siliconate anions of the general formula RSi(OH)_a[OSiR(OH),(0 ),]_δ(0 )_c (defined as above, with R = R³), charge balanced by alkali-metal cations, such that the organosilicon compound has at least one hydrophobic organic group covalently bonded to a silicon atom.

[0028] In the formula R 3 _xSiZ 1₄-_x representing at least one silane (a) present as the

1 2 organosilicon compound, each group Z is selected from the group consisting of -OR , -CI,

2 1 and -OH, where R is a C₁-C₄ hydrocarbyl. Thus, non- limiting examples of group Z include, in addition to chloro and hydroxyl groups, methoxy, ethoxy, n-propoxy, isopropoxy, n-butoxy, isobutoxy, sec-butoxy, and tert-butoxy. In general, groups Z¹ are groups that readily hydrolyze in the presence of water, typically being replaced with a hydroxyl group after the hydrolysis.

[0029] In the formula R 3 _xSiZ 1₄-_x representing at least one silane present as the

organosilicon compound, each group R is selected from the group consisting of Ci-Cs hydrocarbyl, C3-C8 fluorohydrocarbyl, phenyl, tolyl, and R⁴, such that at least one group R³ in the organosilicon compound is C₄-Cs hydrocarbyl, Ci-C₆ fluorohydrocarbyl, phenyl, tolyl, or R⁴.

[0030] Non-limiting examples of Ci-Cs hydrocarbyl groups as options for group R include methyl, ethyl, n-propyl, isopropyl, n-butyl, isobutyl, sec -butyl, and tert-butyl, and all isomers of pentyl, hexyl, heptyl and octyl. The C₄-Cs hydrocarbyl groups among these Ci- Cs hydrocarbyl groups are n-butyl, isobutyl, sec-butyl, and tert-butyl, and all isomers of pentyl, hexyl, heptyl and octyl.

[0031] Non-limiting examples of C₃-C₈ fluorohydrocarbyl groups as options for group R include n-propyl groups, n-butyl groups, isobutyl groups, sec-butyl groups, and isomers of pentyl, hexyl, heptyl, or octyl groups, in which at least one hydrogen atom, but not all hydrogen atoms are replaced with a fluorine atom. In preferred embodiments, the C₃-C₈ fluorohydrocarbyl group is linear or branched, but not cyclic. In further preferred

embodiments the C₃-C₈ fluorohydrocarbyl group may be expressed by the formula

-(CH₂)_p-(CF₂)_?-CF₃, in which p > 2 and p + q is from 2 to 7. Non- limiting examples of such C₃-C₈ fluorohydrocarbyls include the 3,3,4,4,5,5,6,6,6-nonafluorohexyl group ("NFH"), in which subscript p is 2 and subscript q is 3; the 3,3,3-trifluoropropyl group ("TFP"), in which subscript p is 2 and subscript q is 0; and the 3,3,4,4,5,5,6,6,7,7,8,8,8-tridecafluorooctyl group in which subscript p is 2 and subscript q is 5.

[0032] Additionally, group R may be a phenyl group, i.e., an aromatic -CeH₅ ring.

Group R may be a tolyl group, i.e., an aromatic -CeH₅ ring, in which one hydrogen atom is replaced with a methyl group.

[0033] As noted above, group R³ in the formula R³ _xSizV_x may be a group R⁴. Group R⁴ has the general structure -R⁵-0-(CH₂)r_f-R⁶, in which R⁵ is a C₃ linear alkylene or a C₄-C₅ branched alkylene, R⁶ a Ci-C₆ perfluoroalkyl, and i is 1 or 2. Group R⁵ may be, for example, propylene (-CH₂-CH₂-CH₂-), 2-methylpropylene (-CH₂CH(CH₃)-CH₂-), or 3,3-dimethylpropylene (-CH₂CH₂-CH(CH₃)₂-). Group R⁶ may be any linear, branched, or cyclic alkyl group derived from a hydrocarbyl group having from 1 to 6 carbon atoms and in which all hydrogen atoms are replaced with fluorine atoms. Also, group R⁶ may be a -C₆F5 ring.

[0034] In the group R⁴, group R⁵ is connected on one side to the at least one silane through a carbon-silicon bond and on the opposite side to an oxygen atom. Perfluoroalkyl group R⁶ is not connected directly to the same oxygen atom; rather, group R⁶ is connected to a methylene group (-CH₂-; d = 1), or an ethylene group (-CH₂CH₂-; d = 2) that is connected to the oxygen atom. Thus, the portion of group R⁴ represented by (-R⁵-0-(CH₂)r_f-) functions as a "spacer group" that isolates the fluorine atoms in the group R⁶ from the silicon atom in the at least one silane. Without intent to be bound by theory, it is believed that isolation of the perfluoroalkyl groups R⁶ from the silicon atom adds significant stability to the at least one silane when the at least one silane is dissolved in the aqueous solution containing at least one alkali-metal C₁-C₄ hydrocarbyl siliconate.

[0035] In the formula R 3 _xSiZ 1₄__x representing at least one silane (a) present as the organosilicon compound, the subscript x may be 1, 2, or 3. In preferred embodiments the subscript x is 1 or 2. In more preferred embodiments the subscript x is 1. The subscript x determines the number of hydrophobic groups R present in the at least one silane, relative to the number of easily hydro lyzable groups Z¹. Without intent to be bound by theory, it is believed that dissolution of the silanes in the aqueous solution comprising at least one alkali- metal C₁-C₄ hydrocarbyl siliconate results from replacement of the groups Z¹ with a hydroxyl, siloxane, or siliconate group. It is believed also that the number of groups R present on the at least one silane determines the type of hydrophobic resin that will form when the water-dispersible composition is exposed to atmospheric carbon dioxide. For example, when subscript x is equal to 1, the silane may form an R S1O₃/2 unit ("T-unit") in a silsesquioxane resin. When subscript x is equal to 2, the silane may form an R 2S1O2/2 unit ("D-unit") in a resin. When subscript x is equal to 3, the silane may form an R 3S1O1/2 unit ("M-unit") in a resin.

[0036] The organosilicon compound may comprise at least one phenylsilsesquioxane resin (b) having the formula [PhSi0₃/2]_m[QSi0₃/2]„, in which each Q is a C1-C4 hydrocarbyl; m is from 0.5 to 1 ; n is from 0 to 0.5; and m + n = 1. Thus, groups Q may be selected from methyl, ethyl, n-propyl, isopropyl, n-butyl, isobutyl, sec-butyl, and tert-butyl. In preferred embodiments, group Q is methyl, ethyl, or /? -propyl.

[0037] In the phenylsilsesquioxane resin (b), the subscript m designates the average number of moles of phenylsilsesquioxane units PhSi0₃/2 present in one mole of the phenylsilsesquioxane resin. The subscript n designates the average number of moles of group-Q-silsesquioxane units QS1O₃/2 present in one mole of the phenylsilsesquioxane resin. In preferred embodiments, the subscript m is from 0.6 to 0.9; from 0.5 to 0.8; or from 0.65 to 0.75. Because m + n = 1, in an example of a preferred phenylsilsesquioxane resin, subscript m may be 0.7 and subscript n may be 0.3.

[0038] In further embodiments, the organosilicon compound may comprise a mixture (c) of at least one silane (a) as described above and at least one phenylsilsesquioxane resin (b) as described above.

[0039] In the water-dispersible composition, the solvated organosilicon component may be prepared by adding the organosilicon compound to the aqueous solution comprising the alkali-metal C₁-C₄ hydrocarbyl siliconate described above. Substantial or complete solvation of the organosilicon compound may require heating of a mixture of alkali-metal C₁-C₄ hydrocarbyl siliconate and the organosilicon compound to a temperature of greater than 50 °C, preferably greater than 70 °C, for a period of time such as, for example, 1 to 5 hours, 24 hours, or even up to 72 hours, depending on the organosilicon compound being solvated. Additionally, solvation of the organosilicon compound may require physical manipulation of the mixture of alkali-metal C₁-C₄ hydrocarbyl siliconate and organosilicon compound, such as by mixing, stirring, rolling, shaking, or agitating the mixture while the mixture is held at the elevated temperature for a period of time. The present inventors have found surprisingly that the organosilicon compounds described above are soluble in aqueous solutions of alkali- metal C₁-C₄ hydrocarbyl siliconates, even when the organosilicon compounds comprise higher-alkyl groups such as n-butyl groups or silsesquioxane resins such as

phenylsilsesquioxane resins. Solvation of such compounds in aqueous media previously was not possible using chemistries for directly forming an organosiliconate by mixing an organosilane or a phenylsilsesquioxane with a base such as NaOH or KOH.

[0040] The amount of hydrocarbyl-substituted, fluoroalkyl-substituted, or phenyl- substituted silanes or silsesquioxanes that may be solvated in compositions comprising alkali- metal C₁-C₄ hydrocarbyl siliconates depends on the chain length of the hydrocarbyl or fluoroalkyl group and the concentration of the alkali-metal C₁-C₄ hydrocarbyl siliconate in solution. For example, when the organosilicon compound comprises NFH groups (defined above) as group R , it is believed that a practical limit of solvated components in the water- dispersible aqueous composition is reached at about 10 wt.% solvated organosilicon component in 40 wt.% solvated alkali-metal C₁-C₄ hydrocarbyl siliconate, based on the total weight of the water-dispersible aqueous composition.

[0041] Though certain organosilicon compounds may solvate to a level of greater than 10 wt.%, based on the total weight of the water-dispersible aqueous composition, such compositions may have poor stability on dilution. In general, it is believed that lower concentrations of solvated organosilicon component in the water-dispersible aqueous composition results in a higher level of stability on dilution. In preferred embodiments, the water-dispersible aqueous composition may comprise about 5 wt.% of the solvated organosilicon component and about 40 wt.% of the solvated alkali-metal C₁-C₄ hydrocarbyl siliconate, based on the total weight of the water-dispersible aqueous composition, with water or other inert ingredients being the balance.

[0042] In examples of water-dispersible aqueous compositions, the water-dispersible composition may comprise, based on the total weight of the water-dispersible composition, from 30 wt.% to 60 wt.% of the solvated alkali-metal C₁-C₄ hydrocarbyl siliconate (I); and from 1 wt.% to 20 wt.% of the solvated organosilicon component (II). In preferred examples, the water-dispersible composition may comprise from 35 wt.% to 50 wt.% of the solvated alkali-metal C₁-C₄ hydrocarbyl siliconate (I); and from 2 wt.% to 15 wt.%, or from 2 wt.% to 10 wt.%, of the solvated organosilicon component (II). In preferred examples of water- dispersible aqueous compositions and diluted water-dispersible aqueous compositions, the weight ratio of the solvated alkali-metal C₁-C₄ hydrocarbyl siliconate (I) to the solvated organosilicon component (II) in the water-dispersible composition may be from about 3 : 1 to about 50: 1, preferably from about 4: 1 to about 40: 1. Moreover, preferred examples of water- dispersible aqueous compositions may have a "total-solids content," defined as the total weight portion of the composition derived from the combination of the solvated alkali-metal C₁-C₄ hydrocarbyl siliconate (I) and the solvated organosilicon component (II), of from about 30 wt.% to about 60 wt.%.

[0043] The water-dispersible aqueous compositions preferably are dilution stable, such that part aqueous composition may be diluted in from 1 part to 100 parts of a diluent such as water to yield diluted water-dispersible aqueous compositions. Preferred diluted water- dispersible aqueous compositions may comprise, for example, from 0.3 wt.% to 1 wt.% of the solvated alkali-metal C₁-C₄ hydrocarbyl siliconate (I) and from 0.01 wt% to 0.2 wt.% of the solvated organosilicon component (II). Preferred examples of diluted water-dispersible aqueous compositions may have total-solids contents of from about 0.1 wt.% to about 15 wt.%, more preferably from about 0.3 wt.% to about 10 wt.%, still more preferably from about 0.5 wt.%) about 5 wt.% or from about 0.5 wt.% to about 3 wt.%.

[0044] Further embodiments are directed to methods for forming the water-dispersible aqueous compositions described above. In example methods for forming the water- dispersible aqueous compositions, at least one organosilicon compound in solid or liquid form is reacted with an aqueous solution comprising a solvated alkali-metal C₁-C₄ hydrocarbyl siliconate to form a reaction mixture. The reacting may be accomplished according to various configurations including, but not limited to, the embodiments described below.

[0045] In one example embodiment, the reacting of the at least one organosilicon compound with the aqueous solution may occur in a single step configuration by simply adding the organosilicon compound to a vessel containing the aqueous solution comprising a solvated alkali-metal C₁-C₄ hydrocarbyl siliconate. [0046] In another example embodiment, in a batch configuration, the reacting may comprise a further step prior to the reacting, wherein the solvated alkali-metal C₁-C₄ hydrocarbyl siliconate is formed by adding a silane of the formula R^SiXs to an aqueous solution of an alkali-metal hydroxide such as potassium hydroxide or sodium hydroxide. Thereupon, the organosilicon compound may be added to the solvated alkali-metal C₁-C₄ hydrocarbyl siliconate thus formed.

[0047] In still another example embodiment, the reacting of the at least one organosilicon compound with the aqueous solution may occur in a continuous configuration. In a continuous configuration, water, alkali-metal hydroxide, a silane of the formula R^SiXs, and the organosilicon compound each may be added to a single vessel. In the silane of the formula R^SiXs, R¹ is a C1-C₄ hydrocarbyl, defined as above; and X is a hydro lyzable group such as, for example, a halogen or a group -OZ, where Z is hydrogen or a C1-C₄ hydrocarbyl. This configuration results in formation of the solvated alkali-metal C₁-C₄ hydrocarbyl siliconate in solution and the reacting of the solvated alkali-metal C₁-C₄ hydrocarbyl siliconate with the organosilicon compound in the same solution.

[0048] Regardless of the configuration, in the reacting step to form the reaction mixture, the solvated alkali-metal C₁-C₄ hydrocarbyl siliconate is as defined above with regard to the embodiments of water-dispersible aqueous compositions. The organosilicon compound may be selected from the group consisting of (a) silanes having a formula R 3 _xSiZ 1₄-_x; (b) phenylsilsesquioxane resins having an average formula [PhSi03/₂]_m[QSi03/₂]«; and (c)

3 1 1

mixtures of (a) and (b). In the formula R _xSiZ ₄-_x, each Z is selected from the group

2 2 3 consisting of -OR , -CI, and -OH; each R is a C1-C₄ hydrocarbyl; each R is selected from the group consisting of Ci-Cs hydrocarbyl, C3-C₈ fluorohydrocarbyl, phenyl, tolyl, and R⁴, such that at least one group R in the organosilicon compound is C₄-Cs hydrocarbyl, C₃-C₈ fluorohydrocarbyl, phenyl, tolyl, or R⁴; R⁴ is -R⁵-0-(CH₂)r_f -R⁶, where d is 1 or 2 ; R⁵ is a C₃ linear alkylene or a C₄-Cs branched alkylene; R⁶ is a Ci-C₆ perfluoroalkyl; and x is 1, 2, or 3. In the formula [PhSi03/₂]_m[QSi03/₂]«, each Q is a Ci-C₄ hydrocarbyl; m is from 0.5 to 1 ; n is from 0 to 0.5; and m + n = 1. Each of the R groups may be defined as above with respect to the water-dispersible compositions.

[0049] The aqueous solution may comprise from 20 wt.% to 60 wt.%, preferably from 30 wt.% to 50 wt.%, more preferably from 35 wt.% to 45 wt.% of the solvated alkali-metal Ci-C₄ hydrocarbyl siliconate, based on the total weight of the aqueous solution. Preferably, an amount of the organosilicon compound is added to the aqueous solution, such that the reaction mixture comprises from 1 wt.% to 20 wt.%, preferably from 5 wt.% to 15 wt.%, more preferably from 5 wt.% to 10 wt.% of the organosilicon compound. The addition of the organosilicon compound to the aqueous solution may occur in any suitable reaction vessel, such as a laboratory-scale jar, beaker, or flask, or an industrial-scale reactor, provided the reaction vessel is chemically inert to the alkali-metal C₁-C₄ hydrocarbyl siliconate and the organosilicon compound.

[0050] The method for forming the water-dispersible aqueous compositions further may comprise heating the reaction mixture to a reaction temperature of from 50 °C to 150 °C. In preferred embodiments, the reaction mixture is heated to a reaction temperature of from 80 °C to 120 °C. A higher reaction temperature of at least 80 °C may be preferred to minimize the amount of time necessary for the organosilicon compound to react with and dissolve in the aqueous solution.

[0051] The method for forming the water-dispersible aqueous compositions further may comprise manipulating the reaction mixture until the organosilicon compound is completely dissolved in the reaction mixture. The manipulating may involve any practical form of manipulation such as, for example, mixing, stirring, rolling, shaking, agitating, or sonicating. Typically, the reaction mixture is manipulated while the reaction temperature of from 50 °C to 150 °C is maintained. The most reactive organosilicon compounds may require no manipulation to react and dissolve in the reaction mixture. Solvation of less-reactive organosilicon compounds may require the reaction mixture to be manipulated for up to 72 hours. Typically, the organosilicon compounds dissolve completely within the reaction mixture after from 1 hour to 24 hours of manipulation at the reaction temperature of from 50 °C to 150 °C. Preferred water-dispersible aqueous compositions comprise alkali-metal C₁-C₄ hydrocarbyl siliconates and organosilicon components that both are completely solvated. As such, organosilicon components that do not completely dissolve within the reaction mixture after 72 hours of manipulation of the reaction mixture at the reaction temperature of from 50 °C to 150 °C are not preferred.

[0052] Optionally, the method for forming the water-dispersible aqueous compositions further may comprise aging the reaction mixture at any stage for a sufficient amount of time to maximize the amount of product formed. Optionally, the method for forming the water- dispersible aqueous compositions further may comprise removal of hydrolysis byproducts such as alcohols from the reaction mixture. Removal of the byproducts may occur by distillation or other appropriate means. The removal of the byproducts may purify the water- dispersible composition or may reduce the flammability of the water-dispersible composition, particularly when alcohols are removed. [0053] Further embodiments are directed to a method for treating a substrate surface using at least one of the water-dispersible aqueous compositions described above. The substrate surface is typically an outer surface of a substrate. The substrate may be any porous material for which sealing or waterproofing of a surface of the substrate is desirable such as a porous construction material, for example. Examples of such substrates include, but are not limited to, brick, stone, masonry, concrete, asphalt, wood, gypsum, paper, combinations thereof, and assemblies or materials comprising any of these such as, for example, sidewalks, wallboard, and roofing shingles.

[0054] In the method for treating the substrate surface, a coating of a water-dispersible aqueous composition is applied to the substrate surface to form a treated substrate surface. The water-dispersible aqueous composition may comprise a total-solids content of from 0.1 wt.% to 45 wt.%, based on the total weight of the water-dispersible aqueous composition. The total-solids content is derived from the amount of the water-dispersible aqueous composition consisting of a combination of a solvated alkali-metal C1-C4 hydrocarbyl siliconate, as defined above, and a solvated organosilicon component. The solvated organosilicon component is derived from the group consisting of (a) silanes having a formula

3 1

R _xSiZ 4-_x; (b) phenylsilsesquioxane resins having an average formula [PhSi0_3/2]_m[QSi0_3/2]„; and (c) mixtures of (a) and (b).

[0055] In the formula R 3 _xSiZ 1₄-_x, each Z1 is selected from the group consisting of -OR 2 ,

2 3

-Cl, and -OH; each R is a C₁-C₄ hydrocarbyl; each R is selected from the group consisting of Ci-Cs hydrocarbyl, C3-C8 fluorohydrocarbyl, phenyl, tolyl, and R⁴, such that at least one group R in the organosilicon compound is C₄-Cs hydrocarbyl, C3-C8 fluorohydrocarbyl, phenyl, tolyl, or R⁴; R⁴ is -R⁵-0-(CH₂)r_f-R⁶, where <i is 1 or 2 ; R⁵ is a C3 linear alkylene or a C₄-C₅ branched alkylene; R⁶ is a Ci-C₆ perfluoroalkyl; and x is 1, 2, or 3. In the formula [PhSi0_3/2]_m[QSi0_3/2]„, each Q is a Ci-C₄ hydrocarbyl; m is from 0.5 to 1; n is from 0 to 0.5; and m + n = 1. Each of the R groups may be defined as above with respect to the water- dispersible compositions. The weight ratio of the solvated alkali-metal Ci-C₄ hydrocarbyl siliconate to the solvated organosilicon component in the water-dispersible composition may be from 3: 1 to 50: 1, preferably from 4: 1 to 40: 1, more preferably from 10: 1 to 20: 1.

[0056] The water-dispersible aqueous composition may be applied to the substrate surface by any practical means, using any suitable applicator. For example, the composition may be applied by brushing, rolling, or spraying. In the case of relatively small articles, such as bricks or blocks, the composition may be applied by dipping. Preferably, the composition is applied to the substrate surface at a coverage of from 50 g to 500 g of water-dispersible aqueous composition per square-meter of substrate surface to facilitate even coverage and penetration. At this level of coverage, the coating may have a depth of penetration of from about 0.1 mm to about 10 mm, for example, depending upon the porosity of the substrate and amount of treatment contained in the composition. Additional benefits may be realized by multiple applications to the substrate surface after a first coating is allowed to dry.

[0057] After the water-dispersible aqueous composition is applied, the treated substrate surface is exposed naturally to atmospheric carbon dioxide to form a cured hydrophobic and, in the case when R is fluorohydrocarbyl, additionally oleophobic layer within the treated substrate surface. Without intent to be limited by theory, it is believed that the hydrophobic and optionally oleophobic layer may comprise an alkali metal carbonate derived from the alkali-metal C1-C4 hydrocarbyl siliconate and a silicone resin derived from the organosilicon component. The hydrophobic layer may further comprise at least one carbonate compound derived from the organosilicon component. Likewise, the silicone resin may comprise at least one structural unit derived from the alkali-metal C₁-C₄ hydrocarbyl siliconate.

Regardless, the treated substrate surface, after exposure to atmospheric carbon dioxide, comprises a silicon resin.

[0058] When a silane-based organosilicon compound is incorporated in the water- dispersible aqueous composition, the silicon resin formed after exposure to atmospheric carbon dioxide may comprise at least one group R , defined as above, imparts hydrophobicity and in the case of R being fluorohydrocarbyl, oleophobicity to the treated substrate surface. When a phenylsilsesquioxane-based organosilicon compound is incorporated in the water- dispersible aqueous composition, the silicon resin formed after exposure to atmospheric carbon dioxide may comprise a plurality of phenyl groups and, optionally, at least one group Q, defined as above, to imparts hydrophobicity to the treated substrate surface.

[0059] Example methods of treating the substrate surface may further comprise diluting a concentrated water-dispersible aqueous composition before the applying of the coating to form the water-dispersible aqueous composition. The concentrated water-dispersible aqueous composition may be acquired by an end-user, for example, after being prepared and packaged by a supplier, for example, and may comprise a total-solids content of from 20 wt.% to 60 wt.%, based on the total weight of the concentrated water-dispersible aqueous

composition. The total-solids content of the concentrated water-dispersible aqueous composition may comprise, consist essentially of, or consist of the combination of the solvated alkali-metal C₁-C₄ hydrocarbyl siliconate and the solvated organosilicon

component. Diluting the concentrated water-soluble aqueous composition may comprise adding a sufficient amount of water to the concentrated water-dispersible aqueous

composition, such that the water-dispersible aqueous composition comprises a total-solids content of from 0.1 wt.% to 45 wt.%, based on the total weight of the water-dispersible aqueous composition, wherein the total-solids content may comprise, consist essentially of, or consist of the combination of the solvated alkali-metal C1-C4 hydrocarbyl siliconate and the solvated organosilicon component.

EXAMPLES

[0060] The present invention will be better understood by reference to the following examples, which are offered by way of illustration and which one of skill in the art will recognize are not meant to be limiting. In the following examples, DC-777 refers to Dow- Corning® 777 water repellent, an aqueous mixture of 42% w/w potassium

methylsilanetriolate (CAS No. [31795-24-1]), 0.9% w/w methanol, and 57.1% w/w water. Potassium methylsilanetriolate is also known as potassium methyl siliconate.

Example 1

[0061] 100 g of DC-777 (containing 42 g potassium methyl siliconate) was weighed into a 236-mL wide-mouth jar, and 10 g of 3,3,4,4,5,5,6,6,6-nonafluorohexyl-trimethoxysilane (NFH-Si(OMe)₃; C₄F CH₂CH₂Si(OCH₃)₃) was added. The jar was capped, placed on a jar roller, and rolled for 24 hours at room temperature (25 °C ± 3 °C). After the 24 hours, the contents of the jar were inspected. The jar contained a clear liquid having some solid masses within the liquid that were white in color and several millimeters in size. The jar was placed into an oven at 80 °C for one hour, then removed from the oven and rolled for one hour at room temperature. On subsequent inspection, it was found that the jar contained a clear solution.

Example 2

[0062] A solution was prepared following the procedure of Example 1 by mixing 100 g of DC-777 (containing 42 g potassium methyl siliconate) with 10 g of

3,3,3-trifiuoropropyltrimethoxysilane (TFP-Si(OMe)₃; F₃CCH₂CH₂Si(OCH₃)₃) instead of with NFH-Si(OMe)₃. The solution was rolled in a jar for 24 hours at room temperature. After the 24 hours and without an additional heating, the jar contained a clear solution. Example 3

[0063] A solution was prepared in a jar following the procedure of Example 1 , except only 5 g of NFH-Si(OMe)3 was mixed with 100 g of DC-777 (containing 42 g potassium methyl siliconate). After the jar was rolled for 24 hours at room temperature, the jar contained a clear solution.

Example 4

[0064] A solution was prepared in a jar following the procedure of Example 2, except only 5 g of TFP-Si(OMe)3 was mixed with 100 g of DC-777 (containing 42 g potassium methyl siliconate). After the jar was rolled for 24 hours at room temperature, the jar contained a clear solution.

Example 5

[0065] A solution was prepared in a jar following the procedure of Example 1 , except only 2.5 g of NFH-Si(OMe)3 was mixed with 100 g of DC-777 (containing 42 g potassium methyl siliconate). After the jar was rolled for 24 hours at room temperature, the jar contained a clear solution.

Comparative Example 1

[0066] An attempt was made to prepare a clear, aqueous siliconate solution of

NFH-Si(OMe)3 without adding potassium methyl siliconate (i.e., DC-777) to the initial mixture. A 100-mL NaOH solution was prepared diluting in a 236-mL jar 6 g of 30% (w/w) aqueous sodium hydroxide with 94 g of deionized (DI) water. Then, 13.8 g of

NFH-Si(OMe)3 was added to the jar. The jar was capped and shaken vigorously for several minutes. The jar was placed in a jar roller and rolled for 24 hours. An inhomogeneous mixture resulted. In particular, the jar contained a clear liquid but also contained a significant amount of a white substance, resembling a precipitate or gel, that adhered to the walls of the jar. Thereupon, the jar and its contents were heated for 24 hours at 80 °C and were rolled an additional 24 hours. Even after the additional heating and rolling of the jar, none of the white substance had dissolved. Then, an additional 6 g of 30% NaOH was added to the mixture, and the jar and its contents were heated 24 hours at 80 °C. The jar was rolled an additional 4 hours at room temperature. The form and amount of the white substance on the walls of the jar remained unchanged. Example 7

[0067] Into a 74-cm wide-mouth jar, 4 g of phenyltrimethoxysilane (PhSi(OMe)₃) and 50 g of DC-777 (containing 21 g potassium methyl siliconate) were added. The jar was capped and rolled for 24 hours at room temperature. A clear solution resulted. This solution was diluted with DI water such that it contained 5% (w/w) silicone. The diluted solution was applied to brick, limestone, and wood (pine). Comparative trials were performed on brick, limestone, and wood (pine) using DC-777 alone, diluted to 5% (w/w) solid content. Three days later a drop of water was placed on the surface of each treated substrate, and the drop was examined over the course of one hour. From the appearance of the drop, the

hydrophobing ability of the treatment could be ascertained. In particular, a large contact angle would indicate good hydrophobicity, but tendency of the water droplet to spread would indicate poor hydrophobicity.

[0068] Based on the behavior of the drops of water on the various substrates, surfaces of the substrates treated with PhSi(OMe)₃ dissolved in DC-777 were consistently more hydrophobic than the surfaces of the substrates treated with DC-777 alone. The composition containing PhSi(OMe)₃ performed especially well on the wood substrate, compared to the composition containing only DC-777.

Example 8

[0069] Into a 74-cm wide-mouth jar, 2 g of Dow Corning Z-6018 Intermediate (a solid- flake silsesquioxane resin made up of 70 mol.% PhSi0_3/2 units and 30 mol.% /?-PrSi0_3/2 units) and 50 g of DC-777 (containing 21 g potassium methyl siliconate) were added. The jar was capped and rolled for 24 hours. A clear solution resulted. Another second composition was prepared by dissolving 3 g of the Z-6018 in 50 g of DC-777 and rolling for 24 hours. The two compositions were diluted to 5% silicone and were applied to brick and wood in the same manned described in Example 7. Both compositions produced a hydrophobic surface on brick and wood.

Comparative Example 2

[0070] Into a 74-cm wide-mouth jar, 30 g of DC-777 (containing 12.6 g potassium methyl siliconate) and 3.0 g of Wacker MK Resin (a solid, powdered methyl silicone resin available from Wacker Chemie, AG). The jar was capped and was rolled on ajar roller for 24 hours. A substantial portion of the powder resin remained visible in the liquid after the 24 hours of rolling. The jar was heated in a 70 °C oven for 2 hours, followed by additional rolling for 2 hours. A significant portion of the white resin had not dissolved and had agglomerated into several large lumps. The jar was heated again at 70 °C for 24 hours and was rolled for another 4 hours. Much of the solid resin remained in the jar as several large white lumps. Again the jar was heated for a further 72 hours at 70 °C, followed by 4 hours of rolling. Still no more resin had dissolved.

Anti-Staining Tests

[0071] The stain resistance benefits imparted to substrates by treatment with the siliconate compositions of Examples 1-5 were assessed. Two additional test specimens were prepared as bases for comparison by treating the additional test specimens with DC-777 (described above) or with Zonyl^® 8740 (product of DuPont containing approximately 30 wt.% of a proprietary perfluoroalkyl methacrylic copolymer and 70 wt.% water). Each treatment agent (i.e., the siliconates from Examples 1-5, DC-777, and Zonyl^® 8740) was diluted with deionized water to a solids content of 3% (w/w). A limestone test specimen was prepared for each treatment agent by applying 0.75 mL of one of the 3% treatment agents to a

2 2

5 cm 7.5 cm (0.0038 m") area of the test specimen, to provide a coverage of 200 mL/m . The treatment agent was allowed to remain on the surface of the limestone test specimen for 10 minutes, after which the remaining solution was removed by soaking the liquid into a paper towel. The treated test specimens were allowed to dry at room temperature for 72 hours before further testing.

[0072] To test the stain resistance of the treated test specimens, 1 mL of a staining agent was applied to the surface of the test specimen and allowed to remain on the surface for 24 hours at room temperature. Oil-based staining agents (motor oil and olive oil) and water- based staining agents (black coffee and red wine) were tested. For oil-based staining agents, any excess oil was removed after the 24 hours by blotting the oil drops with tissue paper. For water-based staining agents that had dried after the 24 hours, the staining agents were rehydrated by placing 1 mL of water on each the stain area, and the rehydrating water was removed by blotting each drop with tissue paper.

[0073] The stain-treated test specimens were examined, and a qualitatively determined number was assigned to each staining agent based on the appearance of the stain. A value of 5 meant that no visibly discernable evidence of the stain remained on the surface of the test specimen. A value of 4 indicated a very slight trace of the stain remained. A value of 3 indicated the presence of some staining, but with minimal spreading of the stain. A value of 2 indicated significant staining with some spreading. A value of 1 indicated staining at the level of an untreated surface, including very significant staining and spreading along the grains of the test specimen. The numbers from this staining evaluation were totaled to give an overall score, with perfect total score being 20 (value of 5 for each of the four staining agents). The results are shown in TABLE 1.

TABLE 1: Anti-staining benefits imparted to treated limestone test specimens.

[0074] The results from these tests indicate that siliconate compositions prepared with NFH-Si(OMe)3 (Examples 1, 3, and 5) imparted a higher level of stain resistance to the limestone test specimens than did the siliconate compositions prepared with TFP-Si(OMe)3 (Examples 2 and 4). Stain-resistance imparted by siliconates prepared according to

Examples 1 and 3 and containing NFH-Si(OMe)3 met or exceeded that of Dupont's

Zonyl^® 8740. All siliconates prepared with fluoroalkylsilanes showed a higher level of stain- resistance benefit than the DC-777 control. Additionally, the siliconate treatment agents from Examples 1 and 3, both prepared with NFH-Si(OMe)3, gave the same anti-staining performance, even though the treatment agent of Example 3 was prepared with half as much NFH-Si(OMe)3 as was the treatment agent of Example 1.

Claims

1. A water-dispersible aqueous composition comprising:

(I) a solvated alkali-metal C₁-C₄ hydrocarbyl siliconate; and

(II) a solvated organosilicon component derived from an organosilicon compound selected from the group consisting of:

(a) silanes having a formula R 3 _xSiZ 1₄-_x;

(b) phenylsilsesquioxane resins having an average formula

[PhSi0_3/2]_m[QSi0_3/2]„; and

(c) mixtures of (a) and (b);

where:

1 2

each Z is selected from the group consisting of -OR , -CI, and -OH; each R is a C₁-C4 hydrocarbyl;

each R is selected from the group consisting of Ci-Cs hydrocarbyl, C₃-C8 fluorohydrocarbyl, phenyl, tolyl, and R⁴, such that at least one group R in the organosilicon compound is C₄-Cs hydrocarbyl, C₃-Cs fluorohydrocarbyl, phenyl, tolyl, or R⁴;

R⁴ is -R⁵-0-(CH₂ R⁶, where d is 1 or 2;

R⁵ is a C₃ linear alkylene or a C4-C5 branched alkylene;

R⁶ is a Ci-C₆ perfluoroalkyl;

x is 1, 2, or 3;

each Q is a Ci-C₄ hydrocarbyl;

m is from 0.5 to 1;

n is from 0 to 0.5; and

m + n = 1.

2. The water-dispersible aqueous composition of claim 1, wherein both the alkali-metal C₁-C₄ hydrocarbyl siliconate and the organosilicon component are completely solvated within the water-dispersible aqueous composition.

3. The water-dispersible aqueous composition of claim 1 or claim 2, wherein the water- dispersible aqueous composition is devoid of solid particulate matter derived from the organosilicon compound.

4. The water-dispersible aqueous composition of any one of claims 1 to 3, wherein the alkali-metal C₁-C₄ hydrocarbyl siliconate is selected from the group consisting of lithium Ci- C₄ hydrocarbyl siliconates, sodium Ci-C₄ hydrocarbyl siliconates, potassium Ci-C₄ hydrocarbyl siliconates, and mixtures thereof.

5. The water-dispersible aqueous composition of any one of claims 1 to 4, wherein the alkali-metal Ci-C₄ hydrocarbyl siliconate is selected from the group consisting of sodium methyl siliconate, potassium methyl siliconate, and mixtures thereof.

6. The water-dispersible aqueous composition of any one of claims 1 to 5, wherein the water-dispersible aqueous composition comprises, based on the total weight of the water- dispersible aqueous composition:

from 0.3 wt.% to 60 wt.% of the solvated alkali-metal Ci-C₄ hydrocarbyl siliconate; and

from 0.01 wt.% to 20 wt.% of the solvated organosilicon component.

7. The water-dispersible aqueous composition of any one of claims 1 to 6, wherein each Z¹ is selected from the group consisting of methoxy, ethoxy, n-propoxy, isopropoxy, n-butoxy, -CI, and -OH.

8. The water-dispersible aqueous composition of any one of claims 1 to 7, wherein the organosilicon compound is selected from silanes having the formula R 3 _xSiZ 1₄-_x.

9. The water-dispersible aqueous composition of claim 8, wherein:

x is 1;

each Z¹ is selected from the group consisting of methoxy, ethoxy, n-propoxy,

isopropoxy, n-butoxy, -CI, and -OH; and

R is phenyl.

10. The water-dispersible aqueous composition of claim 8 or claim 9, wherein:

x is 1; each Z is selected from the group consisting of methoxy, ethoxy, n-propoxy, isopropoxy, n-butoxy, -CI, and -OH; and

3 3 each R is selected from Ci-Cs hydrocarbyl groups, such that at least one group R the organosilicon compound is C₄-Cs hydrocarbyl.

The water-dispersible aqueous composition of any one of claims 8 to 10, wherein: x is 1;

each Z¹ is selected from the group consisting of methoxy, ethoxy, n-propoxy,

isopropoxy, n-butoxy, -CI, and -OH;

R is a fluorohydrocarbyl having a formula -(CH₂)_p-(CF₂)_?-CF₃;

p≥2; and

p + q is from 3 to 7.

12. The water-dispersible aqueous composition of any one of claims 1 to 7, wherein the organosilicon compound is selected from the phenylsilsesquioxane resins having the average formula [PhSi0_3/2]_m[QSi0_3/2]„.

13. A method for forming a water-dispersible aqueous organosilicon composition, the method comprising:

reacting an organosilicon compound with an aqueous solution comprising a solvated alkali-metal C₁-C₄ hydrocarbyl siliconate to form a reaction mixture, the organosilicon compound being selected from the group consisting of:

(a) silanes having a formula R 3 _xSiZ 1₄-_x;

(b) phenylsilsesquioxane resins having an average formula

[PhSi0_3/2]_m[QSi0_3/2]„; and

(c) mixtures of (a) and (b);

where:

1 2

each Z is selected from the group consisting of -OR , -CI, and -OH; each R is a Ci-C₄ hydrocarbyl;

R⁴ is -R⁵-0-(CH₂)_rf -R⁶, where d is 1 or 2; R⁵ is a C₃ linear alkylene or a C₄-C5 branched alkylene;

R⁶ is a Ci-C₆ perfluoroalkyl;

x is 1, 2, or 3;

each Q is a C₁-C₄ hydrocarbyl;

m is from 0.5 to 1;

n is from 0 to 0.5; and

m + n = 1 ; and

manipulating the reaction mixture until the organosilicon compound is completely dissolved therein to form the water-dispersible aqueous organosilicon composition.

14. The method of claim 13, further comprising heating the reaction mixture to a reaction temperature of from 50 °C to 150 °C.

15. The method of claim 13 or claim 14, wherein manipulating the reaction mixture comprises mixing, stirring, rolling, shaking, agitating, or sonicating the reaction mixture for up to 72 hours.