Emulsifiable resin

Abstract

The present disclosure provides a composition including an aqueous dispersion including an aqueous medium as a continuous phase and a dispersed phase including a polyurethane resin and a hydrophobic component, which can include a hydrophobic crosslinker and / or a hydrophobic catalyst.

Description

[0001] Cross-reference to related applications

[0002] This application claims priority under 35 U.S.C. 119 to the following prior U.S. provisional applications: Serial No. 63 / 767,190, filed March 5, 2025, entitled “Emulsifiable Resin”; Serial No. 63 / 565,264, filed March 14, 2024, entitled “High Solids Coating Composition”; and Serial No. 63 / 565,239, filed March 14, 2024, entitled “Controlled Curing Coating Composition”, all of which are incorporated herein by reference. Technical Field

[0003] This disclosure relates to a composition comprising a polyurethane resin and a hydrophobic component. Background Technology

[0004] Coatings can be applied to a variety of substrates to provide color and other visual effects, corrosion resistance, abrasion resistance, chemical resistance, etc. In addition, various types of coatings (such as coatings applied to packaging, automobiles, and various substrates) can be formed from compositions that can be cured to form coatings. Summary of the Invention

[0005] This disclosure provides a composition comprising an aqueous dispersion comprising an aqueous medium as a continuous phase and a dispersed phase comprising a polyurethane resin and a hydrophobic component, the hydrophobic component comprising a hydrophobic crosslinking agent and / or a hydrophobic catalyst. Detailed Implementation

[0006] This disclosure provides a composition (which may be curable and may alternatively be referred to as a coating composition) and a method for preparing it. The composition of this disclosure exhibits high solids content and low viscosity.

[0007] I. Definition

[0008] For the purposes of the following detailed description, it should be understood that this disclosure may take various alternative variations and sequences of steps unless the contrary is explicitly stated. Furthermore, except in any operational instance, or where otherwise indicated, all figures used in the specification and claims to indicate, for example, the quantity of an ingredient, should be understood to be modified by the term “about” in all cases. For example, numerical ranges provided for the weight percentage of a component or the amount of added component should be interpreted as being modified by the term “about.” Therefore, unless indicated to the contrary, the numerical parameters set forth in the following specification and appended claims are approximations that may vary depending on the desired properties to be obtained through this disclosure. At least, and not in an attempt to limit the application of the doctrine of equivalence to the scope of the claims, each numerical parameter should be interpreted at least according to the number of significant figures reported and by applying common rounding techniques.

[0009] Although the numerical ranges and parameters described in this disclosure are approximate, the values ​​illustrated in specific examples are reported as precisely as possible. However, any numerical value inherently contains some error that is necessarily caused by the standard deviation found in its corresponding test measurement results.

[0010] Furthermore, it should be understood that any numerical range described herein is intended to include all subranges included therein. For example, the range “1 to 10” is intended to include all subranges from the described minimum value of 1 to the described maximum value of 10 (and include both the minimum and maximum values), that is, a minimum value equal to or greater than 1 and a maximum value equal to or less than 10.

[0011] Unless otherwise specified, the use of the singular includes the plural, and the plural encompasses the singular. Additionally, unless otherwise specified, the use of "or" means "and / or," even if "and / or" may be explicitly used in certain instances.

[0012] When used in this document, “solid-based acid value” indicates the quantitative acidity of a given chemical substance based on the number of milligrams (mg) of potassium hydroxide (KOH) required to neutralize the acidic component in 1 gram of non-volatile component.

[0013] Unless otherwise specified, the ambient temperature and pressure conditions are ambient temperature (20-25°C, such as 23°C) and standard pressure of 101.3 kPa (1 atmosphere), with relative humidity in the air ranging from 35% to 75%, such as 55%.

[0014] As used herein, the term "aqueous dispersion" refers to a dispersion in which the continuous phase comprises at least 30 wt% (such as at least 50 wt%) of water based on the total weight of the continuous phase.

[0015] As used herein, the terms “aqueous dispersibility” and “water dispersibility” and similar terms refer to the following property of a material: when 1 gram of the material is added to 100 ml of an aqueous medium or water, it forms a dispersion that does not separate and / or coalesce after three hours under ambient conditions, or, if it partially separates after three hours under ambient conditions, it reverts to an aqueous dispersion form upon stirring.

[0016] As used herein, the term "primer" refers to a coating applied to a primer layer, another primer layer, and / or applied directly to a substrate, optionally including components that affect color and / or provide other visual effects (such as colorants). A clear coat may be applied over the primer layer.

[0017] As used herein, the term "adhesive" refers to a component in a coating composition that binds the components of the coating composition together. Adhesives may include, but are not limited to, acrylic polymers, polyurethanes, polyesters, epoxy polymers, melamine resins, and alkyd polymers.

[0018] As used herein, the terms “crosslinker,” “reactant,” and similar terms refer to a molecule that includes at least one functional group that can react with groups of another molecule (such as polyurethane) in a curable composition, such as, but not limited to, epoxy, (meth)acrylate, isocyanate, amino plastic, aziridine, and / or carbodiimide.

[0019] As used herein, the term “cure / curing” refers to the use of a compound (“curing agent”) that can participate in a chemical reaction that leads to crosslinking and / or polymerization between monomers, oligomers, prepolymers and / or polymers.

[0020] As used herein, the terms “curing agent,” “crosslinker,” and “crosslinking agent” refer to compounds that can participate in chemical reactions that lead to crosslinking and / or polymerization between monomers, oligomers, prepolymers, and / or polymers.

[0021] As used herein, the term "direct gloss finish" refers to a coating applied to at least a portion of a substrate or another coating that imparts a decorative and / or protective finish to the substrate.

[0022] As used herein, the term "film-forming component" refers to an ingredient in a coating composition and may include polymers, resins, crosslinking materials, or any combination thereof that are part of the film-forming mechanism of the coating composition. As a non-limiting example, the film-forming component may be dried or cured by exposure to elevated temperatures (e.g., above 40°C), photochemical radiation, or under ambient conditions.

[0023] As used herein, the terms “flash” or “flash off” refer to the removal of solvents that allow the applied coating composition to remain liquid and evaporate.

[0024] As used herein, the term "hydrophobic component" refers to a compound comprising at least 50% by weight of one or more molecules that have a solubility of less than 5 mg / ml in deionized water under ambient conditions.

[0025] As used herein, unless otherwise stated, “isocyanate equivalent weight” and “NCO equivalent weight” refer to the equivalent weight of isocyanate (NCO) (in grams per eq), determined using ASTM D2572-19 (Standard Method for Isocyanate Groups in Polyurethane Materials or Prepolymers) as described herein.

[0026] As used herein, the terms “flash” or “flash off” refer to the removal of solvents that allow the applied coating composition to remain liquid and evaporate.

[0027] As used herein, the term "(meth)acrylate" is intended to include both methacrylates and acrylates, with non-limiting examples including esters of acrylic acid and esters of methacrylate.

[0028] As used herein, the term "single coating" refers to a coating used to finish the surface of a substrate without subsequently applying another coating (such as a clear coat), which may be a single coating (such as a topcoat).

[0029] As used herein, the terms “multifunctional” and “bifunctional” refer to molecules having more than two or two functional groups, respectively. As a non-limiting example, when used in conjunction with isocyanates, it means that each molecule has more than one isocyanate functionality.

[0030] Unless otherwise specified, as used herein, the term "molecular weight" refers to the weight-average molecular weight ("Mw") determined by gel permeation chromatography (GPC) using appropriate polystyrene standards. If a number-average molecular weight ("Mn") is specified, the weight is determined by the same GPC method while calculating the number mean based on the polymer molecular weight distribution data obtained therefrom. As a non-limiting example, Mn refers to the total weight of the material divided by the number of molecules in the material and can be determined by gel permeation chromatography. Unless otherwise specified, Mw and Mn are expressed in g / mol.

[0031] As used herein, the term "organic solvent" refers to carbon-containing molecules, and non-limiting examples include esters, ketones, glycol ethers, alcohols, hydrocarbons, and mixtures thereof, which are capable of dissolving or dispersing other substances under ambient conditions.

[0032] As used herein, the prefix "poly" refers to two or more. By way of non-limiting examples, polyisocyanate refers to a compound containing two or more isocyanate groups, and polyol refers to a compound containing two or more hydroxyl groups.

[0033] "Polymer" and "polymerization" refer to oligomers, polymers, homopolymers (e.g., prepared from a single monomeric substance), copolymers (e.g., prepared from at least two monomeric substances), terpolymers (e.g., prepared from at least three monomeric substances), and graft polymers.

[0034] As used herein, the term "primer" refers to a base coat that can be applied to a substrate to prepare a surface for the application of a protective or decorative coating composition.

[0035] "Resin solids" refers to the non-volatile components of the binder or film-forming components that constitute the composition. As used herein, a weight percentage based on "resin solids" means the amount of the component based on the total weight of the binder or film-forming components of the composition.

[0036] As used herein, the terms “solids,” “total solids,” and “total resin solids” refer to the non-volatile components present in a composition comprising volatile and non-volatile components. As used herein, the weight percentage based on “solids,” “total solids,” and / or “total resin solids” refers to the amount of a component based on the total weight of the non-volatile components of the composition, determined by comparing the weight of an initial sample with the weight of a final sample after exposure to 110°C for one hour. “High solids” refers to a composition having a solids level of at least 25% by weight based on the weight of the composition.

[0037] As used herein, the term "solvent" refers to a substance that can dissolve or disperse other substances under environmental conditions.

[0038] As used herein, the term "surfactant" refers to a substance that, when added to a liquid, reduces the surface tension of the liquid, thereby increasing the liquid's spreading and wetting properties.

[0039] As used herein, the term "topcoat" refers to a coating applied over at least a portion of another coating.

[0040] This disclosure provides a composition that can be a curable composition or alternatively referred to as a coating composition. The composition comprises an aqueous dispersion comprising polyurethane. The polyurethane resin described herein is capable of emulsifying the hydrophobic portion, resulting in increased solids and / or decreased viscosity compared to compositions not having the disclosed emulsifying properties.

[0041] This disclosure provides an aqueous dispersion comprising a polyurethane resin and a hydrophobic component. Optionally, the hydrophobic component may be a separate component, wherein the component does not form covalent bonds with the polyurethane resin. The polyurethane resin may include water-dispersible groups, wherein the water-dispersible groups may include ionic and / or nonionic groups (such as acid groups, polyether groups, nonreactive amine groups, hydroxyl groups, thiol groups, and / or similar groups).

[0042] The hydrophobic component may comprise 0.01% to 70.00% by weight (such as 1% to 60% by weight) of the total resin solids of the composition.

[0043] As used in this article, the phrase “weight%” refers to a percentage of weight.

[0044] II. Polyurethane resin

[0045] Polyurethane resins can be used as binders or film-forming resins in curable compositions and can be prepared using methods known in the art. Polyurethanes can be prepared by reacting isocyanate-reactive compounds (such as, but not limited to, hydroxyl-functionalized compounds, thiol- or mercapto-functionalized compounds, and / or primary or secondary amines) with polyisocyanates. Polyurethane resins can be nonionic or ionic and may include functional groups (such as acid groups, hydroxyl groups, thiol groups, alkyl groups, and / or reactive amine groups), or may be non-functionalized. These functional groups can contribute to the aqueous dispersibility of the polyurethane resin.

[0046] Polyurethane resins may have a weight-average molecular weight greater than 800 g / mol and a number-average molecular weight (Mn) of at least 400 g / mol (such as at least 500 g / mol, or at least 1000 g / mol, at least 1000 g / mol, or at least 2000 g / mol, or at least 3000 g / mol) and at most 50,000 g / mol (such as at most 40,000 g / mol, or at most 30,000 g / mol, or at most 5000 g / mol), or in any range (such as 400 g / mol to 50,000 g / mol, or 500 g / mol to 40,000 g / mol, or 1000 g / mol to 30,000 g / mol) using any of the foregoing values ​​as endpoints, as determined by gel permeation chromatography using polystyrene standards.

[0047] The compositions disclosed herein (which may be curable compositions) may comprise an amount of polyurethane resin in the range of 1 wt% (such as 5 wt%, or 30 wt%, or 40 wt%, or 50 wt%, or 60 wt%) to up to 70 wt% (such as up to 80 wt%, or up to 85 wt%), or in any range (such as 1 wt% to 85 wt%, or 5 wt% to 80 wt%, or 30 wt% to 70 wt%) using any of the foregoing values ​​as endpoints, wherein the wt% is based on total resin solids.

[0048] i. Polyisocyanate

[0049] The polyurethane disclosed herein can be derived from polyisocyanates (such as diisocyanates) and, as a non-limiting example, can react with isocyanate reactive compounds.

[0050] Suitable polyisocyanates can be aliphatic, aromatic, alicyclic, or heterocyclic isocyanates. Suitable aliphatic isocyanates may include trimethylene diisocyanate, tetramethylene diisocyanate, pentamethylene diisocyanate, hexamethylene diisocyanate, 1,2-propylidene diisocyanate, 1,2-butylidene diisocyanate, 2,3-butylidene diisocyanate, and 1,3-butylidene diisocyanate; cycloalkylene compounds (such as 1,3-cyclopentane diisocyanate, 1,4-cyclohexane diisocyanate, 1,2-cyclohexane diisocyanate, and isophorone diisocyanate); aromatic compounds (such as m-phenylene diisocyanate, terephthalene diisocyanate, 4,4'-diphenyl diisocyanate, 1,5-naphthalene diisocyanate, and 1,4-naphthalene diisocyanate); and aliphatic-aromatic compounds (such as 4,4'-diphenylmethane diisocyanate). 2,4- or 2,6-toluene diisocyanate or mixtures thereof, 4,4'-toluidine diisocyanate, tetramethylphenyldimethyl diisocyanate and phenyldimethyl diisocyanate; nucleosubstituted aromatic compounds (such as bianisidine diisocyanate, 4,4'-diphenyl ether diisocyanate and chlorophenylene diisocyanate); triisocyanates (such as triphenylmethane-4,4',4"-triisocyanate, 1,3,5-triisocyanophenyl, hexamethylene diisocyanate isocyanurate trimer and 2,4,6-triisocyanotoluene); and tetraisocyanates (such as 4,4'-dimethyldiphenylmethane-2,2',5,5'-tetraisocyanate); polymeric polyisocyanates (such as toluene diisocyanate dimers and trimers, etc.).

[0051] Suitable diisocyanates also include those having a single aromatic or alicyclic ring (such as isophorone diisocyanate (IPDI), tetramethylxylene diisocyanate (TMXDI), 4,4'-methylene dicyclohexyl diisocyanate (H12MDI), 1,6-hexamethylene diisocyanate (HDI), 1,3-bis(isocyanomethyl)cyclohexane, 1,5-diisocyano-2-methylpentane, 1,6-diisocyano- 2,2,4-Trimethylhexane, 1,6-Diisocyanate-2,4,4-Trimethylhexane, 1,4-Diisocyanate-butanone, Trimethylhexamethylene diisocyanate, 1,8-Diisocyanate-octane, 1,12-Diisocyanate-dodecane, 1,8-Diisocyanate-2,4-Dimethyloctane, 1,4-bis(isocyanate-methyl)cyclohexane, trans-1,4-cyclohexene diisocyanate, and 2,4-Diisocyanate-1-methylcyclohexane.

[0052] Other suitable aliphatic diisocyanates may also include: methyl-2,6-diisocyanohexanoate, bis(isocyanomethyl)cyclohexane, 1,3-bis(isocyanomethyl)cyclohexane, 2,5(6)-bis(isocyanomethyl)cyclo[2.2.1.]heptane, 1,3,3-trimethyl-1-(isocyanomethyl)-5-isocyanocyclohexane, octahydro-4,7-methylbridge-1H-indene diisocyanate and 1,1'-methylenebis(4-isocyanocyclohexane).

[0053] ii. Isocyanate reactive compounds

[0054] The polyurethane disclosed herein can be formed from isocyanate-reactive compounds, such as primary or secondary amine functional compounds, thiol functional compounds, and hydroxyl functional compounds that can react with the isocyanate of the polyisocyanate. The hydroxyl functional compounds can be, but are not limited to, hydroxyl-functional polyesters, polycarbonates, polyethers, polyetheramines (such as those available from Huntsman International LLC under the trade name Jeffamine), or acrylic polymers. The thiol functional compounds can include, but are not limited to, C2-C... 20 Alkyl dithiols (such as dodecanedithiols).

[0055] The hydroxyl group in a hydroxyl-functionalized compound can be linked by a bridging group selected from the following: alkylene; alkenylene; alkyneylene; or arylene. Hydroxyl-functionalized compounds may lack an acid group (such as non-acidic polyols).

[0056] Hydroxyl functional compounds include, but are not limited to, alkylene glycols (such as ethylene glycol, propylene glycol, diethylene glycol, dipropylene glycol, triethylene glycol, tripropylene glycol, hexanediol, polyethylene glycol, polypropylene glycol, and neopentyl glycol); hydrogenated bisphenol A; cyclohexanediol; propylene glycol, including 1,2-propanediol, 1,3-propanediol, butylethylpropanediol, 2-methyl-1,3-propanediol, and 2-ethyl-2-butyl-1,3-propanediol; butanediol, including 1,4-butanediol, 1,3-butanediol, etc. Alcohols and 2-ethyl-1,4-butanediol; pentanediol, including trimethylpentanediol and 2-methylpentanediol; cyclohexanediol; hexanediol, including 1,6-hexanediol, caprolactone diol (such as the reaction product of ε-caprolactone with ethylene glycol), hydroxyalkylated bisphenols; polyether diols (such as poly(oxytetramethylene) diol and polytetrahydrofuran); trimethylolpropane; pentaerythritol; dipentaerythritol; trimethylolethane; trimethylolbutane; dimethylolcyclohexane; glycerol, etc., or combinations thereof.

[0057] Hydroxyl functional compounds can be non-acidic polyols, meaning that polyols lack acid groups.

[0058] Hydroxyl-functionalized polyesters, poly(meth)acrylates, and polycarbonates can be suitable hydroxy-functionalized compounds that react with polyisocyanates to form polyurethane resins. As used herein and as will be understood by those skilled in the art, the term "(meth)acrylate" refers to both acrylate and the corresponding (meth)acrylate. Poly(meth)acrylates can be any suitable poly(meth)acrylate or mixtures thereof. Poly(meth)acrylates may include di(meth)acrylates, tri(meth)acrylates, tetra(meth)acrylates, and / or one or more other olefinically unsaturated free radical polymerizable monomers. Mixtures of poly(meth)acrylate monomers, including mono, di, tri, and / or tetra(meth)acrylates, may also be used.

[0059] Hydroxyl-functionalized compounds include, but are not limited to, the following: ethylene glycol; 1,2-propanediol; 1,3-propanediol; 1,2-butanediol; 1,3-butanediol; 1,4-butanediol; 2-buten-1,4-diol; 2,3-butanediol; 2-methyl-1,3-propanediol; 2,2'-dimethyl-1,3-propanediol (neopentyl glycol); 1,5-pentanediol; 3-methyl-1,5-pentanediol; 2,4-diethyl-1, 5-Pentanediol; 1,6-Hexanediol; 2-Ethyl-1,3-Hexanediol; Diethylene glycol; Triethylene glycol; Dipropylene glycol; Tripropylene glycol; 2,2,4-Trimethylpentane-1,3-diol; 1,4-Cyclohexanediol; Tricyclodecanediol; 2,2,4,4-Tetramethylcyclobutane-1,3-diol; Isosorbide; 1,4-Cyclohexanediol; 1,1′-Isopropylidene bis(4-cyclohexanol); and mixtures thereof.

[0060] Suitable hydroxyl-functionalized compounds may include polyether glycols (such as Terathane® 250 and Terathane® 650 available from Invista, or PolyTHF® polyether glycol available from BASF).

[0061] A. Acid-functionalized polyurethane resin

[0062] When using acid-functional polyurethane resins, the polyurethane resins can be prepared without restriction by incorporating acid-containing polyols, hydroxy acids (such as hydroxypentanoic acid), and / or mercapto acids (such as 3-mercaptopropionic acid).

[0063] As a non-limiting example, acid-functional polyurethanes can be prepared by reacting a polyester polyol, polycarbonate polyol, polyether polyol, or acrylic polyol with a polyisocyanate and an acid-functional polyol (such as dimethylolpropionic acid) such that the NCO / OH stoichiometric ratio is greater than 1:1 to generate an NCO-functional prepolymer. The terminal isocyanate can then be reacted with a non-tertiary amino alcohol (such as diethanolamine or ethanolamine) to produce a terminal OH-functional polymer. Then, some or all of the terminal OH groups can be reacted with an acid anhydride (such as succinic anhydride or methylhexahydrophthalic anhydride) to produce a polyurethane with terminal COOH groups. The acid groups introduced in the first stage of polyurethane preparation are considered internal COOH groups, while the acid groups introduced after the reaction of the anhydride with the amino alcohol are considered terminal COOH groups. The acid-functional polyurethane polymer can be neutralized with a tertiary alkylated amine before and / or after contact with water to provide water dispersibility.

[0064] As an alternative, non-limiting example, the terminal isocyanate group can react with the acid monomer. The acid group introduced in the first stage of polyurethane preparation is considered an internal COOH group, while the acid group introduced after reaction with the acid monomer is considered a terminal COOH group. Acid-functionalized polyurethane polymers can be neutralized with tertiary alkylated amines before and / or after contact with water to provide water dispersibility (uniform distribution of the acid-functionalized polyurethane in water).

[0065] Acid-functional polyurethanes can also be formed, without limitation, by utilizing the ring-opening of cyclic anhydrides. This can be accomplished by forming a prepolymer from isocyanates, isocyanate-reactive compounds (such as non-acid-containing polyols, acid-containing polyols), and / or combinations thereof. After the prepolymer is formed, reactive amines and / or polyols containing hydroxyl groups can be added to react sequentially with the remaining unreacted isocyanate groups, allowing the anhydride to react with the hydroxyl groups of the prepolymer. Neutralizing amines can then be used to disperse the polyurethane in water.

[0066] Polyurethane can also be formed from an excess of isocyanate, isocyanate reactive compounds (such as, but not limited to, acid-containing polyols), and optionally, non-acid-containing polyols. The prepolymer can then be reacted with a non-acid-containing isocyanate reactive compound, which may contain hydroxyl groups, thiol groups, and / or non-tertiary amine groups, and can then be reacted with a neutralizing amine to disperse the polyurethane in water.

[0067] Polyurethanes can also be formed without limitation by incorporating acids into polyurethane resins. Prepolymers can be formed from isocyanates, isocyanate-reactive compounds (such as acid-containing polyols, non-acid-containing polyols), and / or combinations thereof. The acid monomers can then be reacted with the remaining isocyanate groups in the prepolymer, and the polyurethane can be dispersed in water using neutralizing amines.

[0068] Acid-functional polyurethane resins may have an acid value based on solids greater than 8 mg KOH / g (such as greater than 10 mg KOH / g based on resin solids, such as greater than 13 mg KOH / g, or greater than 15 mg KOH / g, or greater than 25 mg KOH / g), and may be up to 150 mg KOH / g based on resin solids (such as up to 140 mg KOH / g, or up to 130 mg KOH / g), or any range using any of the foregoing values ​​as endpoints (such as 10 mg KOH / g to 150 mg KOH / g, 13 mg KOH / g to 140 mg KOH / g, or 15 mg KOH / g to 130 mg KOH / g). The acid value of acid-functional polyurethane resins may be determined using a Metrohm 798 MPT Titrino automatic titrator manufactured by Metrohm AG according to ASTM D4662-15. This value is then divided by the solids content to obtain the solids-based acid value. The acid groups of polyurethane can be neutralized to enable the polyurethane to be dispersed in water.

[0069] B. Nonionic polyurethane

[0070] Nonionic polyurethanes may include nonionic functional groups, or may contain no or substantially no functional groups. Functional nonionic polyurethanes can be prepared by first reacting an isocyanate-reactive compound with a polyisocyanate such that the NCO / isocyanate-reactive group ratio is greater than 1:1 to generate an NCO-functionalized prepolymer. Then, a terminal isocyanate can be reacted with a compound having multiple isocyanate-reactive groups to provide a functional nonionic polyurethane. Alternatively, functional nonionic polyurethanes can be prepared by first reacting an isocyanate-reactive compound with a polyisocyanate such that the NCO / isocyanate-reactive group ratio is less than 1:1 to generate a polyurethane with non-NCO-functionalized nonionic groups. Nonionic polyurethanes may include hydroxyl, thiol, and / or amine functional groups, which can contribute to the water dispersibility of the polyurethane resin.

[0071] i. Thiol-functionalized polyurethanes

[0072] The polyurethane resin disclosed herein contains a thiol functional group. Suitable compounds are polythiol- or mercapto-based compounds, as well as compounds comprising both thiol- or mercapto- and hydroxyl functional groups, which can react with the isocyanate groups of an NCO-functionalized prepolymer to form the polyurethane resin.

[0073] Suitable polythiols or polythiol compounds may include, but are not limited to, C2-C 20 Alkyl dithiols (such as dodecanedithiols, trimethylolpropane tris(2-mercaptoacetate), trimethylolpropane tris(2-mercaptopropionate), 1,8-dimercapto-3,6-dioxaoctane, thiol-terminated polyethers, pentaerythritol tetra(3-mercaptopropionate), pentaerythritol tetra(2-mercaptoacetate), 2,3-bis((2-mercaptoethyl)thio)-1-propanethiol, 2,3-dithio(2-mercapto)-1-propanethiol, and thiol-terminated polyethers).

[0074] Suitable compounds that simultaneously include both thiol or mercapto and hydroxyl functional groups may include, but are not limited to, dithiothreitol; polyesters, poly(meth)acrylates, and polycarbonates containing mercapto and hydroxyl functional groups; 2,3-dimercapto-1-propanol; and compounds according to the following formula:

[0075]

[0076] Where R 1 It can be at least C2 (such as C3 or C6 to C). 20The polymer backbone may contain straight-chain, branched, or cyclic aliphatic and / or aromatic groups, or may include O, N, and / or S heteroatoms, wherein y is 1 to 100 (such as 1 to 50 or 1 to 25); x may be 1 to 50 (such as 1 to 30, 1 to 20, 1 to 10 or 1 to 5), wherein the SH group is bonded to a carbon atom; and z may be 0 to 60 (such as 1 to 40, 1 to 30, 1 to 20, 1 to 10 or 1 to 5), wherein the OH group is bonded to a carbon atom.

[0077] Polyurethanes containing thiol functional groups can be derived from mixtures comprising polyisocyanates and a certain amount of compounds comprising 15% by weight (such as 20% by weight, or 25% by weight) to 30% by weight (such as 35% by weight, or 40% by weight, or 50% by weight, or 60% by weight, or 70% by weight), or any range (such as 15% by weight to 70% by weight, such as 20% by weight to 60% by weight, or 25% by weight to 50% by weight) of thiol groups or mercapto groups, wherein the weight percentages are based on the total resin solids of the mixture.

[0078] ii. Hydroxyl-functionalized polyurethane

[0079] Hydroxyl-functional nonionic polyurethanes can be prepared as described above, wherein the hydroxyl-functional compounds may include, but are not limited to, the hydroxyl-functional polyesters, polycarbonates, polyethers and / or polyols listed above.

[0080] iii. Amine-functionalized polyurethanes

[0081] Amine-functional nonionic polyurethanes can be prepared as described above, wherein the amine functional compounds may include, but are not limited to, primary or secondary amine functional compounds, such as amine-functional polyesters, polyetheramines, non-tertiary amino alcohols (such as diethanolamine or ethanolamine), and diamines (such as alkyl diamines, such as ethylenediamine, diaminobutane and diaminohexane).

[0082] III. Aqueous Dispersions

[0083] Aqueous dispersions include one or more of the aforementioned polyurethanes dispersed in an aqueous medium. The aqueous dispersion may include an aqueous medium, wherein the solvent comprises at least 30% by weight water, such as at least 40% by weight water, such as at least 50% by weight water. The aqueous dispersion may include a dispersed phase and a continuous phase, the dispersed phase comprising a polyurethane resin and a hydrophobic component, and the continuous phase comprising the aqueous medium.

[0084] IV. Hydrophobic components

[0085] The hydrophobic component may include reactants (such as crosslinking agents) and / or catalysts. The hydrophobic component may include reactants that can react with polyurethane and / or other components of the composition. Reactants may include one or more reactive functional groups. Reactive functional groups may include epoxy, (meth)acrylate, isocyanate, amino plastic, aziridine, and / or carbodiimide. Reactants may be referred to as crosslinking agents, particularly when the reactant includes more than one reactive functional group.

[0086] The hydrophobic component may comprise 0.01% to 70.00% by weight (such as 1% to 60% by weight) of the total resin solids of the composition.

[0087] The crosslinking agent may include functional groups, and the molar ratio of the crosslinking agent functional groups to the polyurethane resin functional groups is 0.25:1.75 (such as 0.5:1.5, or 0.75:1.25, or 0.17:1.1, or 0.75:1, or 0.5:1), or any ratio within the range of the foregoing ratios (such as 0.25:1.75 to 0.5:1).

[0088] The composition may contain a crosslinking agent in an amount from 10% by weight (such as 15% by weight, or 30% by weight, or 40% by weight) to up to 70% by weight (such as up to 60% by weight, or up to 50% by weight), or in any range (such as 10% by weight to 70% by weight, or 15% by weight to 60% by weight, or 30% by weight to 60% by weight, or 40% by weight to 50% by weight) using any two of the foregoing values ​​as endpoints, wherein the weight percentage is based on the total resin solid weight of the coating composition.

[0089] Catalysts may include organometallic catalysts and / or inorganic catalysts. Organometallic catalysts include, but are not limited to, catalysts with carbon-metal bonds, dibutyltin catalysts, zinc catalysts, tin catalysts, titanium catalysts, zirconium catalysts, etc. Catalysts may include organic catalysts, including but not limited to amines, quaternary ammonium compounds, phosphorus-containing compounds, compounds containing quaternary phosphorus groups, etc. Catalysts may include hydrophobic bismuth catalysts, such as bismuth neodecanoate.

[0090] Conventional aqueous compositions may not be effective at utilizing many catalysts, such as bismuth catalysts, because these catalysts are incompatible with aqueous compositions or dispersions. This disclosure addresses one or more problems of conventional compositions by providing an efficient emulsifier resin in which the addition and level of catalyst can be controlled and adjusted according to specific needs. Conventional compositions may correlate catalyst levels with the resin support, thus limiting possible formulations.

[0091] The composition may contain a catalyst in amounts from 0.1 wt% (such as 0.5 wt%, or 1 wt%) to up to 5 wt% (such as up to 4.5 wt%, up to 4 wt%, up to 2 wt%, or up to 1.1 wt%), or in any range using any of the foregoing values ​​as endpoints (such as 0.1 wt% to 5 wt%, or 0.1 wt% to 4.5 wt%, or 0.5 wt% to 4 wt%), wherein the wt% is based on the resin solids weight of the coating composition. For example, if a composition comprises 100 g of resin solids, then 1 wt% of catalyst would be 1 g of catalyst.

[0092] The composition may include other additives optionally as part of the hydrophobic component, including but not limited to surfactants, surface treatment agents, plasticizers, antioxidants, hindered amine light stabilizers, ultraviolet absorbers and / or stabilizers, rheology control agents, thixotropic agents, fillers, reactive diluents, leveling agents, defoamers, abrasive carriers, colorants (such as pigments or dyes), and other additives known to those skilled in the art.

[0093] Aqueous dispersions may include film-forming components, which may include binders and crosslinking agents.

[0094] This disclosure provides a method for coating a substrate. Common methods include applying the composition of this disclosure onto at least a portion of the substrate using techniques such as blade coating, spraying, roller coating, coil coating, dip coating, precision coating, electrodeposition coating, or spin coating. The method may then include curing the composition to form a cured layer on the substrate. The emulsifying properties of the composition may allow catalyst release for coating curing. The composition may be cured at a temperature of 10°C to 210°C for 5 seconds to 168 hours.

[0095] Before curing the applied curable composition, the composition can be flash-dried at a temperature of 10°C to 40°C for 0 to 60 minutes.

[0096] As noted herein, the substrate may include a previously applied coating. As a non-limiting example, this coating composition may be part of a multilayer coating composition. As a non-limiting example, this coating composition may be a coating applied over a primer coating or a coating applied over a base coat.

[0097] Depending on the specific intended use, this coating composition can be applied as a primer, base coat, topcoat (such as a clear coat), or as a direct gloss topcoat or a single coat.

[0098] Applying this coating composition yields a coating having a thickness from 0.5 µm to 250 µm (e.g., 0.5 µm to 200 µm, or 0.5 µm to 150 µm, or 0.5 µm to 100 µm, or 0.5 µm to 75 µm, or 0.5 µm to 65 µm, or 0.5 µm to 55 µm, or 0.5 µm to 52 µm, or 1 µm to 250 µm, or 1 µm to 200 µm, or 1 µm to 100 µm, or 1 µm to 65 µm, or 1 µm to 60 µm, or 1 µm to 55 µm, or 5 µm to 250 µm, or 5 µm to 200 µm, or 5 µm to 100 µm, or 5 µm to 65 µm, or 5 µm to 60 µm, or 5 µm to 55 µm). The dry film thickness (µm) is measured according to ASTM D7091-21.

[0099] The compositions disclosed herein may include multiple components, one of which includes polyurethane, and different components include hydrophobic components. The compositions may include multiple components, one of which includes polyurethane and a hydrophobic component, and different components include film-forming components. Prior to application, the components of the multiple-component composition are combined and then applied to a substrate.

[0100] The compositions disclosed herein may include a single component (1K), wherein the single component comprises a polyurethane and a hydrophobic component.

[0101] As a non-limiting example, the coating composition described herein can be applied by forming a coating on at least a portion of a substrate. Methods may include applying the coating composition to at least a portion of the substrate; and exposing the coating composition to sufficient energy for a sufficient duration to allow the coating composition to cure, such as through a reaction of a polyurethane resin and / or other film-forming components with a crosslinking agent.

[0102] The coating composition can be applied using methods known in the art, such as spraying, scraping, brushing, dipping and / or precision application.

[0103] As noted above, the substrate may include a previously applied coating. As a non-limiting example, this coating composition may be part of a multilayer coating composition. As a non-limiting example, this coating composition may be a coating applied over a base coat or a coating applied over a primer coat, such as this coating being a primer layer.

[0104] The substrate may include iron, steel, aluminum, plastic, wood, composite materials, glass, synthetic materials, paper, leather and / or another coating.

[0105] The coating composition can be cured without restriction by exposure to environmental conditions, elevated temperatures, and / or photochemical radiation.

[0106] When the coating composition is cured by exposure to high temperatures, the temperature can be from 40°C to 240°C (such as 45°C to 210°C, or 50°C to 140°C), for 5 seconds to 168 hours.

[0107] The single-component compositions disclosed herein may be electrodepositable compositions comprising a polyurethane and a hydrophobic component. The emulsifying properties of the composition allow a catalyst to be released during or after the electrodeposition coating process for curing.

[0108] A one-component composition can be applied using a method comprising the steps of: electrophoretically applying the composition as an electrodepositable coating composition to at least a portion of a substrate, and curing the coating composition to form a at least partially cured coating on the substrate. According to this disclosure, the method may include (a) electrophoretically depositing the electrodepositable one-component coating composition of this disclosure onto at least a portion of a substrate; and (b) heating the coated substrate to a temperature and time sufficient to cure the electrodeposited coating on the substrate. According to this disclosure, the method may optionally further include (c) directly applying one or more pigment-containing coating compositions and / or one or more pigment-free coating compositions to the at least partially cured electrodeposited coating to form a topcoat over at least a portion of the at least partially cured electrodeposited coating; and (d) heating the coated substrate from step (c) to a temperature and time sufficient to cure the topcoat.

[0109] When the single-component composition is a cationic electrodepositable coating composition, it can be deposited on a conductive substrate by contacting the composition with a conductive cathode and a conductive anode, wherein the surface to be coated is the cathode. After contact with the composition, an adhesive film of the coating composition is deposited on the cathode when a sufficient voltage is applied between the electrodes. The conditions for performing electrodeposition are known in the art. The applied voltage can vary and can be, for example, from as low as one volt to as high as several kilovolts, such as between 50 volts and 500 volts. The current density can be between 0.5 amperes per square foot and 15 amperes per square foot, and tends to decrease during electrodeposition, indicating the formation of an insulating film.

[0110] Once the cationic electrodepositable coating composition is electrodeposited onto at least a portion of a conductive substrate, the coated substrate is heated to a temperature and time sufficient to at least partially cure the electrodeposited coating on the substrate. As described above, a one-component electrodepositable coating composition can be cured by heating the coated substrate to a temperature in the range of 120°C to 230°C (such as 135°C to 200°C, or 140°C to 180°C). The curing time may depend on the curing temperature and other variables, such as the film thickness of the electrodeposited coating, the level and type of catalyst present in the composition, etc. For the purposes of this disclosure, all that is necessary is sufficient time to achieve curing of the coating on the substrate. As a non-limiting example, the curing time may range from 10 minutes to 60 minutes (such as 20 minutes to 40 minutes). The thickness of the resulting cured electrodeposited coating may range from 15 micrometers to 50 micrometers.

[0111] According to this disclosure, when the one-component composition is an anionically electrodepositable coating composition, the composition can be deposited on a conductive substrate by contacting the composition with a conductive cathode and a conductive anode, wherein the surface to be coated is the anode. After contact with the composition, when a sufficient voltage is applied between the electrodes, an adhesive film of the coating composition is deposited on the anode. The conditions for performing electrodeposition are known in the art. The applied voltage can vary and can be, for example, from as low as one volt to as high as several kilovolts, such as between 50 volts and 500 volts. The current density can be between 0.5 amperes per square foot and 15 amperes per square foot, and tends to decrease during electrodeposition, indicating the formation of an insulating film.

[0112] Once the anion-electrodeposited coating composition is electrodeposited onto at least a portion of a conductive substrate, the coated substrate can be heated to a temperature and maintained for a time sufficient to at least partially cure the electrodeposited coating on the substrate. The one-component anion-electrodeposited coating composition can be cured at temperatures ranging from 90°C to 230°C (e.g., 135°C to 200°C, or 140°C to 180°C). The curing time can depend on the curing temperature and other variables, such as the film thickness of the electrodeposited coating, the level and type of catalyst present in the composition, etc. The curing time can range from 10 minutes to 60 minutes (e.g., 20 minutes to 40 minutes). The thickness of the resulting cured electrodeposited coating can range from 15 micrometers to 50 micrometers.

[0113] The coating compositions described herein may have at least 10 wt% (such as at least 20 wt%, or at least 21 wt%, or at least 22 wt%, or at least 23 wt%, or at least 24 wt%, or at least 25 wt%, and at most 85 wt%, such as at most 65 wt%, such as at most 50 wt%, or at most 45 wt%, or at most 42 wt%); or 10 wt% to 85 wt% (such as 20 wt% to 85 wt%, such as 20 wt% to 65 wt%, such as 20 wt% to 50 wt%, or 21 wt% to 45 wt%, or 22 wt% to 42 wt%, or 25 wt% to 42 wt%) of total resin solids (as described above).

[0114] The compositions described herein may have a viscosity of 1 cps to 5000 cps (such as 10 cps to 500 cps, or 20 cps to 100 cps), which is measured using a cone-plate viscometer (such as the CAP 2000 viscometer available from Brookfield (AMETEK Brookfield)) at 25°C and 900 rpm using rotor No. 1.

[0115] The cured layer formed by the method of this disclosure can have solvent resistance for at least 100 MEK double swabs using the method described herein.

[0116] V. Properties of Curable Compositions

[0117] Compared to precursors for curable compositions, curable compositions formed using this disclosure may exhibit higher solvent resistance. The curable compositions of this disclosure may be completely VOC-free.

[0118] i. Solvent resistance test

[0119] To test the resistance of the curable composition, the substrate coated with the curable composition can be subjected to the solvent resistance test as described below.

[0120] Solvent resistance testing can be performed by placing the test plate on a flat table or other suitable flat, sturdy surface.

[0121] Disposable wipes (such as WypAllL30, available from Kimberly-Clark Worldwide, Inc.) are folded to approximately one inch square to test the solvent resistance of cured test panels.

[0122] The wiping wipes are saturated with a suitable solvent (such as methyl ethyl ketone (MEK)) for use on the test substrate. The wiping wipes are resaturated every 25 double wipes.

[0123] Immediately wipe the substrate coated with the curable composition on the test area with a saturated wipe using a 2-inch to 4-inch back-and-forth motion.

[0124] You can continue to wipe back and forth, counting each completed forward and backward movement as a "double wipe" until the exposed substrate is exposed in the center of the wiping strip, or until 100 double wipes are achieved.

[0125] Record the number of "double swabs" as the test result. Replace the swabs with new ones between each sample tested.

[0126] The curable composition disclosed herein may have solvent resistance of at least 70 MEK double swabs, at least 80 MEK double swabs, at least 90 MEK double swabs, or at least 100 MEK double swabs.

[0127] The curable compositions disclosed herein may also have a MEK dual-wipe rating of 7 or higher (such as 8 or higher) according to the following levels:

[0128]

[0129] When the coating composition described herein comprises an aqueous dispersion including a polyurethane resin and a hydrophobic component, the stability of the composition can be evaluated as described below.

[0130] ii. Stability Testing

[0131] To test the stability of an aqueous mixture of polyurethane resin and a hydrophobic component, the mixture was prepared and its stability was visually evaluated according to the following levels:

[0132]

[0133] Furthermore, the stability of the polyurethane resin and hydrophobic component mixture can be rated at various time intervals after preparation, such as initial, 3 hours, 3 days or other time intervals as needed.

[0134] aspect

[0135] 1. A composition comprising an aqueous dispersion comprising an aqueous medium as a continuous phase and a dispersed phase comprising a polyurethane resin and a hydrophobic component, the hydrophobic component optionally comprising a hydrophobic crosslinking agent and / or a hydrophobic catalyst.

[0136] 2. The composition according to aspect 1, wherein the aqueous dispersion is characterized by not having phase separation or having reversible phase separation after three hours under ambient conditions.

[0137] 3. The composition according to any of the foregoing aspects, wherein the hydrophobic component comprises a crosslinking agent.

[0138] 4. The composition according to any of the foregoing aspects, wherein the hydrophobic component comprises a crosslinking agent comprising epoxy, acrylate, isocyanate and / or amino plastic functional groups.

[0139] 5. The composition according to any of the foregoing aspects, wherein the hydrophobic component comprises a catalyst.

[0140] 6. The composition according to any of the foregoing aspects, wherein the hydrophobic component comprises a catalyst, the catalyst comprising an organometallic catalyst and / or an inorganic catalyst.

[0141] 7. The composition according to aspect 6, wherein the organometallic and / or inorganic catalyst comprises a hydrophobic bismuth catalyst, a hydrophobic zinc catalyst, a hydrophobic tin catalyst, a hydrophobic titanium catalyst, and / or a hydrophobic zirconium catalyst.

[0142] 8. The composition according to any of the foregoing aspects, wherein the hydrophobic component comprises a catalyst, the catalyst comprising an organic catalyst.

[0143] 9. The composition according to aspect 8, wherein the organic catalyst comprises an amine, a quaternary ammonium compound, a phosphorus-containing compound, and / or a compound containing a quaternary phosphorus group.

[0144] 10. The composition according to any of the foregoing aspects, wherein the hydrophobic component comprises an additive.

[0145] 11. The composition according to aspect 10, wherein the additive comprises surfactants, surface treatment agents, plasticizers, antioxidants, hindered amine light stabilizers, ultraviolet absorbers and / or stabilizers, rheology control agents, thixotropic agents, fillers, reactive diluents, leveling agents, defoamers and / or abrasive carriers.

[0146] 12. The composition according to any of the foregoing aspects, wherein the aqueous dispersion comprises a film-forming component, the film-forming component comprising a binder and a crosslinking agent.

[0147] 13. The composition according to any of the foregoing aspects, wherein the polyurethane resin comprises a water-dispersible group.

[0148] 14. The composition according to any of the foregoing aspects, wherein the polyurethane resin comprises a water-dispersible group, the water-dispersible group comprising an ionic group and / or a nonionic group.

[0149] 15. The composition according to aspect 13, wherein the polyurethane resin comprises a water-dispersible group comprising an acid group, a polyether group, a hydroxyl group, a thiol group, and / or a non-reactive amine group.

[0150] 16. The composition according to any of the foregoing aspects, wherein the polyurethane resin comprises an acid-functionalized polyurethane having an acid value of 10 mg KOH / g to 150 mg KOH / g (such as 13 mg KOH / g to 140 mg KOH / g, or 15 mg KOH / g to 130 mg KOH / g) based on resin solids, according to ASTM D 4662-15.

[0151] 17. The composition according to any of the foregoing aspects, wherein the polyurethane resin comprises a nonionic functional polyurethane comprising a polyether portion and / or a polysulfide portion.

[0152] 18. The composition according to any of the foregoing aspects, wherein the polyurethane resin comprises a functional group comprising a thiol group, a hydroxyl group, an alkyl group, a carboxylic acid group, and / or a reactive amine group.

[0153] 19. The composition according to any of the foregoing aspects, wherein the polyurethane resin comprises a nonionic functional polyurethane containing a thiol functional group.

[0154] 20. The composition according to any of the foregoing aspects, wherein the polyurethane resin comprises an ionicly functionalized polyurethane containing a thiol functional group.

[0155] 21. The composition according to any of the foregoing aspects, wherein the polyurethane resin has a number-average molecular weight of 400 g / mol to 50,000 g / mol (such as 500 g / mol to 40,000 g / mol, or 1,000 g / mol to 30,000 g / mol) as determined by gel permeation chromatography using polystyrene standards.

[0156] 22. The composition according to any of the foregoing aspects, wherein the composition comprises 1% to 85% by weight (such as 5% to 80% by weight, or 30% to 70% by weight) of polyurethane resin of total resin solids.

[0157] 23. The composition according to any of the foregoing aspects, wherein the hydrophobic component accounts for 0.01% to 70% (such as 1% to 60% by weight) of the total resin solids of the composition.

[0158] 24. The composition according to any of the foregoing aspects, wherein the composition has 10% to 85% (such as 20% to 85% by weight, such as 20% to 65% by weight, such as 20% to 50% by weight, or 21% to 45% by weight, or 22% to 42% by weight, or 25% to 42% by weight) of total resin solids based on the weight of the composition.

[0159] 25. The composition according to any of the foregoing aspects, having a viscosity of 1 cps to 5000 cps (such as 10 cps to 500 cps, or 20 cps to 100 cps), measured using a cone-plate viscometer (such as a CAP 2000 viscometer available from Brookfield (AMETEK Brookfield)) at 25°C and 900 rpm using rotor No. 1.

[0160] 26. The composition according to any of the foregoing aspects, wherein the composition is a coating composition.

[0161] 27. The composition according to any of the foregoing aspects, wherein the composition comprises a plurality of components, one of which comprises polyurethane, and the other components comprise hydrophobic components.

[0162] 28. The composition according to any of the foregoing aspects, wherein the composition comprises a plurality of components, one component comprising polyurethane and a hydrophobic material, and another component comprising a film-forming component.

[0163] 29. The composition according to any of the foregoing aspects, wherein the polyurethane is part of the film-forming composition, and when the composition is applied to a substrate and cured, the polyurethane reacts with the other components in the composition.

[0164] 30. The composition according to any of the foregoing aspects, wherein the composition is applied to a substrate and cured.

[0165] 31. The composition according to any one of aspects 1 to 11, wherein the polyurethane does not react with the other components in the composition.

[0166] 32. A method of coating a substrate, the method comprising: applying the composition of any one of aspects 1 to 31 onto at least a portion of the substrate using a spraying, roller coating, roll coating, dip coating, precision coating, blade coating, electrodeposition coating, or spin coating technique; and curing the composition to form a cured layer on the substrate.

[0167] 33. The method according to aspect 32, wherein the composition is cured at a temperature of 10°C to 240°C (such as 40°C to 240°C, or 45°C to 210°C, or 50°C to 140°C) for 5 seconds to 168 hours (such as 10 minutes to 60 minutes, or 20 minutes to 40 minutes).

[0168] 34. The method according to any one of aspects 32 or 33, wherein the composition is flash-dried at a temperature of 10°C to 40°C for 0 to 60 minutes before curing the applied composition.

[0169] 35. The method according to any one of aspects 32 to 34, wherein the cured layer has solvent resistance of at least 70 MEK double wipings (such as at least 80 MEK double wipings, or at least 90 MEK double wipings, or at least 100 MEK double wipings).

[0170] 36. The method according to any one of aspects 32 to 35, wherein the cured layer has a dry film thickness of 0.5 µm to 250 µm (such as 15 µm to 50 µm) as measured according to ASTM D7091-21.

[0171] 37. The method according to any one of aspects 32 to 36, wherein the composition is a primer, a base coat, or a topcoat, such as a clear coat, a direct gloss topcoat, or a single coat.

[0172] 38. A substrate coated according to any one of aspects 32 to 37.

[0173] Example

[0174] The aspects of this disclosure are further illustrated by the following examples. It will be apparent to those skilled in the art that many modifications can be made to the materials and methods without departing from the scope of this disclosure.

[0175] Thiol equivalent weight

[0176] As used herein, “thiol equivalent weight” was determined in the following examples as follows: A sample of thiol-terminated polyurethane (0.2 g to 0.6 g) was dissolved in 1 ml of pyridine and 30 ml of a 1:1 solution of methyl ethyl ketone and toluene. The solution was titrated with 0.1 N iodine solution by colorimetry until a persistent pale yellow color was observed in the solution. The thiol solid equivalent weight was calculated using the following equation.

[0177]

[0178] The reported thiol equivalent weight is the average of three repeated measurements.

[0179] The acid value was determined using a Metrohm 798 MPT Titrino automatic titrator manufactured by Metrohm AG according to ASTM D4662-15. This value was then divided by the total solids content to obtain the acid value based on solids.

[0180] NCO equivalent weight (in grams per equivalent; g / eq) is determined using the following revised ASTM D2572-19 (Standard Method for Isocyanate Groups in Polyurethane Materials or Prepolymers): Before testing the sample, prepare a solution of 78 g of dibutylamine (available from Sigma Aldrich) in 4 L of N-methyl-2-pyrrolidone (available from Fisher Scientific). Accurately weigh the sample, weighing between 1 g and 2 g, into a flask. React the sample with 33 mL of dibutylamine to form a substituted urea. Then back-titrate the excess dibutylamine with a solution of 0.2 N hydrochloric acid in isopropanol (available from Fisher Scientific (Ricca)). The amount of hydrochloric acid used to back-titrate the excess dibutylamine is used to calculate the NCO equivalent weight of the original sample.

[0181] Example 1: Formation of nonionic thiol-functionalized polyurethane dispersions

[0182] Polyurethane resin was prepared according to the formulation in Table 1. The contents of charge 1 were added to a four-necked reaction flask equipped with a stirrer, gas inlet, thermometer, and condenser. After the exothermic reaction subsided, the temperature was raised to 80°C and maintained for 2 hours. Charge 2 was added, followed by charge 3. The reaction was made exothermic. Once the exothermic reaction subsided, the reaction was maintained at 80°C until NCO was undetectable as measured by Fourier transform infrared (FTIR) spectroscopy. The solvent-based resin had a measured solids content of 80.5% by weight and a measured thiol equivalent weight of 441 g / mol iodine based on solids. An aqueous dispersion with 40% by weight was obtained by dispersing 200 g of material into charge 4.

[0183] Table 1: Polyurethane Dispersion PUD-1

[0184]

[0185] Example 2: Formation of thiol-functionalized polyurethane dispersions

[0186] Prepare polyurethane resin according to the formulation in Table 2.

[0187] The contents of charge 1 were added to a four-necked reaction flask equipped with a stirrer, gas inlet, thermometer, and condenser. After the exothermic reaction subsided, the temperature was raised to 80°C and maintained until the NCO equivalent weight exceeded 408 g / eq. The reaction was cooled to 60°C. Charge 2 was added. The reaction was made exothermic. Once the exothermic reaction subsided, the reaction was maintained at 70°C for 1.5 hours. The NCO equivalent weight was measured (theoretical value 485 g / eq, measured value 556 g / eq). Charge 3 was added. The reaction was maintained at 80°C until NCO was undetectable as measured by Fourier transform infrared (FTIR) spectroscopy. Then, 498 g of the mixture was dispersed into the mixture of charges 4 and 5. The dispersion had a measured solids content of 32.2%, a measured thiol equivalent weight of 539 g / mol iodine based on solids, and a measured acid value of 9.2 mg KOH / g based on resin solids.

[0188] Table 2: Polyurethane Dispersion PUD-2

[0189]

[0190] Example 3: Formation of nonionic thiol-functionalized polyurethane dispersions

[0191] Polyurethane resin was prepared according to the formulation in Table 3.

[0192] The contents of charge 1 were added to a four-necked reaction flask equipped with a stirrer, gas inlet, thermometer, and condenser. After the exothermic reaction subsided, the temperature was raised to 80°C and maintained until the NCO equivalent weight exceeded 408 g / eq. The reaction was cooled to 60°C. Charge 2 was added. The reaction was made exothermic. Once the exothermic reaction subsided, the reaction was maintained at 70°C for 4.5 hours. The NCO equivalent weight was measured (theoretical value 485 g / eq, measured value 533 g / eq). Charge 3 was added. The reaction was maintained at 80°C until NCO was undetectable as measured by Fourier transform infrared (FTIR) spectroscopy. Then, 498 g of the mixture was dispersed into a mixture of charges 4 and 5. The dispersion had 36.0% measured solids, a thiol equivalent weight of 483 g / mol iodine based on solids, and a measured acid value of 9.8 mg KOH / g based on resin solids.

[0193] Table 3: Polyurethane Dispersion PUD-3

[0194]

[0195] Example 4: Formation of nonionic hydroxyl-functionalized polyurethane dispersions

[0196] Polyurethane resin was prepared according to the formulation in Table 4.

[0197] The contents of charge 1 were added to a four-necked reaction flask equipped with a stirrer, gas inlet, thermometer, and condenser. After the exothermic reaction subsided, the temperature was raised to 80°C and maintained for 3 hours. The NCO equivalent weight was measured (theoretical value 572 g / eq, measured value 573 g / eq). The reaction was cooled to 60°C. Charge 2 was added. The reaction was maintained at 80°C until NCO was undetectable as measured by Fourier transform infrared (FTIR) spectroscopy. Then, 492 g of the mixture was dispersed in charge 3. This dispersion had a measured solids content of 45.7%.

[0198] Table 4: Polyurethane Dispersion PUD-4

[0199]

[0200] Example 5: Formation of nonionic alkyl polyurethane dispersions

[0201] Polyurethane was prepared according to the formulation in Table 5. The contents of charge 1 were added to a four-necked reaction flask equipped with a stirrer, gas inlet, thermometer, and condenser. After the exothermic reaction subsided, the temperature was raised to 80°C and held for 3 hours. The NCO equivalent weight was measured (theoretical value 555 g / eq, measured value 603 g / eq). The reaction was cooled to 65°C. Charge 2 was added. The reaction was held at 80°C until NCO was undetectable as measured by Fourier transform infrared (FTIR) spectroscopy. Then, 363 g of the mixture was dispersed in charge 3. This dispersion had a measured solids content of 50.2%.

[0202] Table 5: Polyurethane Dispersion PUD-5

[0203]

[0204] Example 6: Formation of acid-functionalized polyurethane dispersions

[0205] Polyurethane was prepared according to the formulation in Table 6. The contents of charge 1 were added to a four-necked reaction flask equipped with a stirrer, gas inlet, thermometer, and condenser. After the exothermic reaction subsided, the temperature was raised to 75°C and maintained for 5 hours. The NCO equivalent weight was measured (1312 g / eq, theoretical value 1290 g / eq). The reaction was cooled to 65°C. Charge 2 was added, followed by charge 3. The reaction was maintained at 75°C until NCO was undetectable as measured by Fourier transform infrared (FTIR) spectroscopy. An aqueous dispersion was produced by adding charges 4 and 5. Charge 6 was added, and the reaction was mixed at room temperature for 30 minutes. Based on resin solids, the final dispersion had a solids content of 35.3% and a theoretical acid value of 101 mg KOH / g.

[0206] Table 6: Polyurethane Dispersion PUD-6

[0207]

[0208] Example 7: Formation of thiol-functionalized polyurethane dispersions

[0209] Polyurethane was prepared according to the formulation in Table 7. The contents of charge 1 were added to a four-necked reaction flask equipped with a stirrer, gas inlet, thermometer, and condenser. After the exothermic reaction subsided, the temperature was raised to 80°C and maintained until the theoretical NCO value (539 g / eq) was reached. The reaction was cooled to 60°C and charge 2 was added. The reaction was then made exothermic. Once the exothermic reaction subsided, the reaction was maintained at 70°C for 90 minutes, and the NCO value was determined to be 1933 g / eq (theoretical value 1167 g / eq). Charge 3 was added, and the reaction was maintained at 70°C until NCO was undetectable as measured by Fourier transform infrared (FTIR) spectroscopy. An aqueous dispersion was produced by adding charges 4 and 5. The final dispersion had a measured solids content of 36.0%, a measured thiol equivalent of 1404 g / mol iodine based on resin solids, and a measured acid value of 13.7 mg KOH / g based on resin solids.

[0210] Table 7: Polyurethane Dispersion PUD-7

[0211]

[0212] Example 8: Formation of Solvent-Based Amination Epoxy Resins

[0213] Epoxy resin-1 was prepared according to the formulation in Table 8. Materials 1 to 5 were charged into a four-necked round-bottom flask equipped with a top stirrer, reflux condenser, thermocouple, and nitrogen inlet. The mixture was heated to 130°C and allowed to exotherm, then the temperature was adjusted to 145°C and held at this temperature for 2 hours. Then, while materials 6 to 7 were charged sequentially, the mixture was cooled to 105°C. At 105°C, materials 8 and 9 were rapidly added sequentially, allowing the mixture to exotherm. Then, the temperature was adjusted to 125°C and held for 1 hour. While cooling, material 10 was charged to obtain an amination epoxy resin solution.

[0214] Table 8: Solvent-based aminated epoxy resins – Epoxy Resin 1

[0215]

[0216] Example 9 – Formulation of a hydrophobic catalyst with an aqueous polyurethane dispersion

[0217] Examples A to C were prepared according to Table 9. Mixture 1 was prepared by combining 9.5 g of PUD-5 (Example 5) with 0.5 g of dibutyltin dilaurate and stirring by hand until a homogeneous dispersion was observed. Examples A to C were prepared by mixing Bayhydrol A2470, followed by the addition of Bayhydur 302 (both available from Covestro AG), then deionized water, and then either Mixture 1 or dibutyltin dilaurate as shown. The formulation was applied to a 4” x 12” steel substrate pre-coated with ED7100 electrophoretic primer (available from ACT TestPanels LLC, Hillsdale, MI) using a 6-mil gap square coater. The film was flash-dried under ambient conditions for 10 minutes before baking in an oven at 60°C for 30 minutes. Each coated plate was tested for solvent resistance 1 hour after being removed from the oven.

[0218] Table 9: Inclusion of dibutyltin dilaurate (in g)

[0219]

[0220] As shown in Table 9 above, Invention Example C exhibits the highest MEK DR rating, indicating that it achieves the maximum degree of curing compared to no catalyst (Example A) or free catalyst (Example B).

[0221] Example 10 – Formulation of a hydrophobic catalyst with an aqueous polyurethane dispersion

[0222] The catalyst mixture was prepared according to Table 10. Materials were added by combining the components in 20 mL vials. The materials were mixed until a homogeneous solution or emulsion was obtained. An initial appearance assessment of the formulation was performed under environmental conditions according to the stability testing methods described above, followed by reassessment after 3 hours and 3 days (Table 11).

[0223] Table 10: Formulations of hydrophobic catalysts with aqueous polyurethane dispersions

[0224]

[0225] Table 11: Appearance of hydrophobic catalysts with aqueous polyurethane dispersions

[0226]

[0227] Examples D through F were prepared according to Table 12. Mixtures were prepared by combining the components in 20 mL vials. The materials were mixed until a homogeneous solution was obtained. Curing tests were performed as follows: using a scraper with a 1-mil gap, the epoxy resin formulation solution was applied to a cold-rolled steel sheet pretreated with C700 zinc phosphate (purchased from ACT Test Panels LLC). The test panels were flash-dried under ambient conditions for 5 to 10 minutes, followed by baking in an oven at 175°C for 30 minutes. All samples yielded continuous films. Curing was assessed by solvent resistance, determined using the MEK double-swipe test described above, as shown in Table 13. Performance retention was tested in two ways: 1) the epoxy resin formulation was aged at room temperature for 4 days, then reapplied and cured; 2) the epoxy resin formulation was reformulated using a catalyst mixture aged at room temperature for 5 days, followed by application and curing as described.

[0228] Table 12: Examples of catalyst mixtures containing epoxy resin and their curability by scraping test

[0229]

[0230] Table 13: Appearance, solvent resistance, and curability by scraping test of catalyst mixtures containing epoxy resin

[0231]

[0232] As shown in the examples of the invention where MEK DR is >100, the catalyst mixture and epoxy resin formulation can still be reapplied after several days, and the curing performance is fully maintained. Formulations using catalyst mixture 4 were not developed because the catalyst (hydrophobic component) lacks stability in the absence of polyurethane.

[0233] Example 11 – Incorporation of Dibutyltin Dilaurate

[0234] Examples G through I were prepared according to Table 14. Formulations were prepared in 20 mL scintillation vials. Coatings were prepared using a 1:1 ratio of thiol equivalents to reactive equivalents (acrylate, epoxy, or isocyanate). The order of addition of the mixtures is listed in the formulation information below. Each formulation was applied using a square doctor blade with an 8-mil gap to ED7100 electrophoretically coated steel plate available from ACT Test Panel Technologies (273 Industrial Dr., Hillsdale, MI 49242). The plates were allowed to flash dry under ambient conditions for 10 minutes, then cured in a 60°C oven for 45 minutes. The plates were allowed to stand for 24 hours, and then their MEK tolerance was assessed.

[0235] Table 14: Preparation and results of Examples G to I (in g)

[0236]

[0237] As shown in Table 14, a variety of curing chemistry systems are presented, including acrylates, epoxy, and isocyanates, each cured using the thiol functional groups of PUD-1. Examples G, H, and I all demonstrate a MEK DR of 100 and a MEK DR rating of 7 or higher. Furthermore, these examples exhibit favorable solids / viscosity relationships that provide useful viscosity at relatively high solids levels.

[0238] Although specific examples of compositions and methods according to this disclosure have been described above for illustrative purposes, it will be apparent to those skilled in the art that various changes may be made to the details of this disclosure without departing from the description as defined in the appended claims.

Claims

1. A composition comprising an aqueous dispersion comprising an aqueous medium as a continuous phase and a dispersed phase comprising a polyurethane resin and a hydrophobic component, wherein the hydrophobic component optionally comprises a hydrophobic crosslinking agent and / or a hydrophobic catalyst.

2. The composition according to claim 1, wherein the aqueous dispersion is characterized by not exhibiting phase separation or exhibiting reversible phase separation after three hours.

3. The composition according to any of the preceding claims, wherein the composition is curable.

4. The composition according to any of the preceding claims, wherein the hydrophobic component comprises a crosslinking agent comprising epoxy, acrylate, isocyanate and / or amino plastic functional groups; and / or a catalyst, such as an organic catalyst, organometallic catalyst and / or inorganic catalyst; and / or an additive.

5. The composition according to any of the preceding claims, wherein the aqueous dispersion comprises a film-forming component, the film-forming component comprising a binder and a crosslinking agent.

6. The composition according to any of the preceding claims, wherein the polyurethane resin comprises a water-dispersible group, the water-dispersible group comprising an ionic group and / or a nonionic group.

7. The composition according to any of the preceding claims, wherein the polyurethane resin comprises an acid-functionalized polyurethane having an acid value of 1 mg KOH / g to 150 mg KOH / g based on resin solids, according to ASTM D 4662-15; and / or comprises a nonionic functionalized polyurethane comprising a polyether portion and / or a polysulfide portion; and / or comprises functional groups comprising thiols, hydroxyl groups, alkyl groups, carboxylic acid groups, and / or reactive amine groups.

8. The composition according to any of the preceding claims, wherein the polyurethane resin has a number-average molecular weight of 400 g / mol to 50,000 g / mol, as determined by gel permeation chromatography using polystyrene standards.

9. The composition according to any of the preceding claims, wherein the composition comprises from 1% to 85% by weight of the polyurethane resin based on total resin solids.

10. The composition according to any of the preceding claims, wherein the hydrophobic component comprises from 0.01% by weight to 70% by weight of the total resin solids.

11. The composition according to any of the preceding claims, wherein the composition is a coating composition.

12. The composition according to any of the preceding claims, wherein the aqueous dispersion is characterized by not exhibiting phase separation after three hours under ambient conditions.

13. The composition according to any of the preceding claims, wherein the composition comprises a plurality of components, one of which comprises the polyurethane, and the other components comprise the hydrophobic component.

14. The composition according to any of the preceding claims, wherein the composition comprises a plurality of components, one component comprising the polyurethane and the hydrophobic material, and another component comprising a film-forming component.

15. A method for coating a substrate, the method comprising: The composition according to any one of claims 1 to 14 is applied to at least a portion of a substrate using a spraying, roller coating, roll coating, dip coating, precision coating, blade coating, electrodeposition coating, or spin coating technique; and the composition is cured to form a cured layer on the substrate.

16. The method of claim 15, wherein the curable composition is cured at a temperature of 10°C to 210°C for 5 seconds to 168 hours, and optionally flash-dried at a temperature of 10°C to 40°C for 0 minutes to 60 minutes prior to curing.

17. The method according to any one of claims 15 or 16, wherein the cured layer has solvent resistance for at least 100 MEK double wiping cycles.

18. The method according to any one of claims 15 to 17, wherein the cured layer has a dry film thickness of 0.5 µm to 250 µm as measured according to ASTM D7091-21.

19. The method according to any one of claims 15 to 18, wherein the composition is a primer, a base coat, or a topcoat, the topcoat being such as a clear coat, a direct gloss topcoat, or a single coat.

20. A substrate coated by the method according to any one of claims 15 to 19.

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