Scratch-resistant and wear-resistant architectural coating

Abstract

The present disclosure provides architectural coatings comprising an aqueous self-crosslinking polymer. The coating provides a solution to the wear and scratch problems of the paint film in high traffic areas and sealed spaces.

Description

Technical Field

[0001] The present disclosure relates generally to the field of waterborne architectural coating compositions, particularly self-crosslinking coating compositions having mar and abrasion resistance, and to methods for their preparation and their use in various architectural applications. Background Art

[0002] Water-based architectural coatings (such as paints) that cover interior walls are often scratched, stained or worn due to daily traffic in the area where the coating composition is applied. These differences may be caused by contact from people or objects (such as shoes or furniture) during office movement. These objects may leave undesirable wear marks on the wall by removing a layer of paint or by leaving residues on the painted surface. Attempts to minimize scratches and wear have not been completely satisfactory, and walls in high traffic areas need to be repainted frequently. Summary of the invention

[0003] Disclosed are architectural coatings containing polymer dispersions composed of the self-crosslinking monomers diacetone acrylamide and adipic acid dihydrazide. Once formulated into semi-gloss architectural coatings, these polymer dispersions improve the abrasion and mar resistance of the coatings.

[0004] In its first form, the present disclosure provides a polymer emulsion composition having a first stage and a second stage, comprising: a monomer containing a ketone group or an aldehyde group; and a crosslinker containing a polyhydrazide, wherein the equivalent ratio of ketone to hydrazide functional groups is in the range of 1:0.6 to 1:1.5.

[0005] In its second form, the present disclosure provides a polymer composition of Form 1, wherein the ketone-containing monomer comprises diacetone acrylamide.

[0006] In its third form, the present disclosure provides the polymer composition of Form 1, wherein the hydrazide-containing cross-linking agent comprises adipic acid dihydrazide.

[0007] In its fourth form, the present disclosure provides the polymer composition of Form 2, wherein the diacetone acrylamide monomer is present in an amount of 2.5 wt% or greater, based on the total weight of the composition.

[0008] In its fifth form, the present disclosure provides the polymer composition of Form 3, wherein the adipic acid dihydrazide or polyhydrazide crosslinking agent is present in an amount of 0.8 wt % or greater, based on the total weight of the composition.

[0009] In its sixth form, the present disclosure provides a polymer composition of any one of forms 1 to 5, wherein the composition further comprises a monomer selected from the group consisting of: methyl (meth)acrylate, 2-ethyl (meth)acrylate, n-butyl (meth)acrylate, tert-butyl (meth)acrylate, isobutyl (meth)acrylate, cyclohexyl (meth)acrylate, 2-ethylhexyl (meth)acrylate, isobornyl (meth)acrylate, 2-octyl (meth)acrylate, styrene, (meth)acrylic acid, itaconic acid, a sulfuric acid monomer, and a phosphorous acid monomer.

[0010] In its seventh form, the present disclosure provides the polymer composition of any one of Forms 1 to 6, wherein the weight ratio of the first stage polymer to the second stage polymer is from 50:50 to 97.5:2.5.

[0011] In its eighth form, the present disclosure provides the polymer composition of any one of Forms 1 to 7, wherein the second stage polymer is present in an amount of 2.5 wt% to 40 wt%, based on the total weight of the composition.

[0012] In its ninth form, the present disclosure provides a polymer composition of any one of Forms 1 to 8, wherein the first stage polymer has a theoretical T of -100°C to 50°C. g .

[0013] In its tenth form, the present disclosure provides a polymer composition of any one of Forms 1 to 9, wherein the second stage polymer has a theoretical T of -50°C to 250°C. g .

[0014] In its eleventh form, the present disclosure provides a polymer composition of any one of forms 1 to 10, wherein the weight % ratio of the aldehyde or ketone monomer of the first stage polymer to the aldehyde or ketone monomer of the second stage polymer is 0.7 to 2.5 based on the total monomer weight of the corresponding stage.

[0015] In its twelfth form, the present disclosure provides an architectural coating composition comprising the polymer composition of any one of Forms 1 to 11.

[0016] In its thirteenth form, the present disclosure provides a building coating composition of form 11, which further comprises one or more of the following: a pigment, a dispersant, a filler, a coalescing agent, a pH adjuster, a plasticizer, a defoamer, a surfactant, a thickener, a biocide, a co-solvent, and combinations thereof.

[0017] In its fourteenth form, the present disclosure provides an architectural coating composition according to claim 11 or claim 12, wherein the coating composition exhibits at least one of the following properties: (i) scratch resistance when scraped with a plastic spoon; (ii) scratch resistance when scraped with a plastic fork; or (iii) abrasion resistance when scraped with a rubber sole, as measured by visual rating of the damage caused to the coating.

[0018] In its fifteenth form, the present disclosure provides a method for preparing a multistage polymer emulsion composition of any preceding claim, the method comprising: (i) preparing a first stage polymer from a first pre-emulsion of monomers and initiator; and (ii) preparing a second stage polymer from a second stage monomer pre-emulsion by feeding the second stage monomer pre-emulsion into the first stage polymer dispersion in the presence of a free radical polymerization initiator. BRIEF DESCRIPTION OF THE DRAWINGS

[0019] The accompanying drawings, which are incorporated in and constitute a part of this specification, illustrate several embodiments of the present disclosure and, together with the description, serve to explain the principles of the present disclosure.

[0020] Figure 1 A pendulum swing apparatus for testing the abrasion resistance of architectural coatings is provided. DETAILED DESCRIPTION

[0021] I. Definitions

[0022] As used herein, the term "comprising" and its variants are used synonymously with the term "including" and its variants, and are open, non-limiting terms. Although the terms "comprising" and "including" have been used herein to describe various embodiments, the terms "consisting essentially of" and "consisting of" can be used in place of "comprising" and "including" to provide more specific embodiments and are also disclosed. The singular forms "a / kind", "the" and "the" used in the present disclosure and the appended claims include plural referents unless the context clearly indicates otherwise. The percentage ranges and other ranges disclosed herein include the endpoints of the disclosed ranges as well as any integers provided in the ranges.

[0023] As used herein, " aqueous medium " refers to the gross weight based on the liquid medium, comprising the liquid medium of at least 50 % by weight water. Based on the gross weight of the liquid medium, such aqueous liquid medium can for example comprise at least 60 % by weight of water, or at least 70 % by weight of water, or at least 80 % by weight of water, or at least 90 % by weight of water, or at least 95 % by weight of water, or 100 % by weight of water. If present, the solvent accounting for the liquid medium being less than 50 % by weight comprises an organic solvent. The non-limiting example of suitable organic solvent comprises polar organic solvent, for example protic organic solvent such as ethylene glycol, glycol ether alcohol, alcohol, volatile ketone, glycol diether, ester and diester. Other non-limiting examples of organic solvent comprise aromatic and aliphatic hydrocarbons.

[0024] In addition, the term "self-crosslinkable" refers to polymer particles having two or more functional groups that react with each other and participate in intramolecular and / or intermolecular crosslinking reactions to form covalent bonds in the absence of any external crosslinking agent. For example, the polymer particles of the present invention may each contain a hydrazide functional group and a ketone and / or aldehyde functional group that react with each other to produce a hydrazone bond. As used herein, terms such as "crosslinking agent" refer to molecules comprising two or more functional groups that can react with other functional groups and can connect two or more monomers or polymer molecules by chemical bonds. It should be understood that self-crosslinkable core-shell particles may also react with a separate crosslinking agent (when present).

[0025] II. Multi-stage self-crosslinkable polymer composition

[0026] Provided herein is a multi-stage self-crosslinkable polymer comprising (i) a first stage having a first copolymer comprising diacetone acrylamide; (ii) a second stage having a second copolymer comprising diacetone acrylamide. The diacetone moiety in the polymer backbone reacts with a polyhydrazide such as adipic acid dihydrazide to form a crosslinked polymer film.

[0027] The weight ratio of the first stage copolymer to the second stage copolymer in the multi-stage particles can be in the range of about 50:50 or greater, about 60:40 or greater, about 70:30 or greater, about 80:20 or greater, about 90:10 or greater, about 95:5 or greater, about 97.5:2.5 or greater, or any value encompassed by these endpoints.

[0028] The second stage copolymer can be present in the multistage particles in an amount of about 2.5 wt % or greater, about 5 wt % or greater, about 10 wt % or greater, about 15 wt % or greater, about 20 wt % or less, about 25 wt % or less, about 30 wt % or less, about 35 wt % or less, about 40 wt % or less, or any value encompassed by these endpoints, such as about 2.5 wt % to about 40 wt %, about 10 wt % to about 25 wt %, about 5 wt % to about 15 wt %, or about 35 wt % to about 40 wt %, based on the total particle weight.

[0029] In some embodiments, the first-order polymer theoretical T g The first-order theoretical T may be about -100°C or higher, about -90°C or higher, about -80°C or higher, about -70°C or higher, about -60°C or higher, about -50°C or higher, about -40°C or higher, about -30°C or higher, about -20°C or lower, about -10°C or lower, about 0°C or lower, about 10°C or lower, about 20°C or lower, about 30°C or lower, about 40°C or lower, about 50°C or lower, or any value encompassed by these endpoints. For example, the first-order theoretical T g It may be about -100°C to about 50°C, about -90°C to about 40°C, about -30°C to about 20°C, or about 10°C to about 50°C, and the like.

[0030] Theoretical T of the second stage polymer g It may be about -50°C or more, about -20°C or more, about 0°C or more, about 20°C or more, about 40°C or more, about 60°C or more, about 80°C or more, about 100°C or more, about 120°C or less, about 140°C or less, about 160°C or less, about 180°C or less, about 200°C or less, about 220°C or less, about 240°C or less, about 250°C or less, or any value included in these endpoints, such as, for example, -50°C to 250°C, 0°C to 180°C, 10°C to 140°C, 20°C to 120°C, 30°C to 120°C, 30°C to 80°C, 10°C to 240°C, or 30°C to 140°C.

[0031] The polymer of two levels may contain one or more reactive functional groups. The term "reactive functional group" refers to an atom, atom group, a functional group or a group having sufficient reactivity to form at least one covalent bond with another co-reactive group in a chemical reaction. Examples of reactive functional groups are ketone functional groups and / or aldehyde functional groups and hydrazide functional groups. Other non-limiting examples of additional reactive functional groups that may be present in the first polymer level or the second polymer level include carboxylic acid groups, amine groups, epoxy groups, hydroxyl groups, thiol groups, carbamate groups, carbodiimide groups, amide groups, urea groups, isocyanate groups (including blocked isocyanate groups), ethylenically unsaturated groups, alkoxysilane groups, and combinations thereof. As used herein, "ethylenically unsaturated" refers to a group having at least one carbon-carbon double bond. Non-limiting examples of ethylenically unsaturated groups include, but are not limited to, (meth)acrylate groups, vinyl groups, and combinations thereof.

[0032] In some embodiments, the weight percent ratio of the ketone or aldehyde monomer of the first stage polymer to the ketone or aldehyde monomer of the second stage polymer can be 1:10 to 1:0.5, 1:5 to 1:0.75, 1:2.5 to 1:1, or 1:0.75 to 1:0.5 based on the total monomer weight of the corresponding stage.

[0033] As described above, the film-forming latex particles have reactive functional groups that constitute the self-crosslinking moiety. After the building composition is applied to the substrate and the aqueous component evaporates, the reactive functional groups crosslink with the crosslinking agent resident in the aqueous phase. Preferred self-crosslinking moieties are formed from monomers such as diacetone acrylamide (DAAM), and suitable crosslinking agents include adipic acid dihydrazide (ADH).

[0034] This in-situ crosslinking results in improved properties compared to paints or building compositions containing non-crosslinkable polymers. Other suitable crosslinkable monomers, such as diacetone methacrylamide (DAMAM), acetoacetoxyethyl methacrylate (AAEM) can be copolymerized with the film-forming monomer to produce self-crosslinkable film-forming latex particles. Suitable diacetone (meth) acrylamide monomers are represented by the formula CH2=CR1C(O)NR2C(O)R3, wherein R1 is hydrogen or methyl; R2 is hydrogen, C1-C4 alkyl or phenyl; and R3 is hydrogen, C1-C4 alkyl or phenyl. For example, the (meth) acrylamide derivative can be diacetone acrylamide (DAAM) or diacetone methacrylamide. Polyhydrazides are used in combination with DAAM or diacetone (meth) acrylamide to form crosslinked polymers. Suitable polyhydrazides are adipic acid dihydrazide, phthalic acid dihydrazide, terephthalic acid dihydrazide, trimellitic acid trihydrazide, and the like.

[0035] The amount of DAAM in the first polymer stage can be 0.5 wt % or greater, 1 wt % or greater, 1.5 wt % or greater, 2 wt % or greater, 2.5 wt % or greater, 3 wt % or greater, 3.5 wt % or greater, 4 wt % or greater, 4.5 wt % or greater, 5 wt % or greater, 10 wt % or greater, or 15 wt % or greater.

[0036] The amount of DAAM in the second polymer stage can be 0.5 wt % or greater, 1 wt % or greater, 1.5 wt % or greater, 2 wt % or greater, 2.5 wt % or greater, 3 wt % or greater, 3.5 wt % or greater, 4 wt % or greater, 4.5 wt % or greater, 5 wt % or greater, 10 wt % or greater, or 15 wt % or greater.

[0037] The total amount of DAAM in the polymer dispersion can be 0.5 wt % or more, 1 wt % or more, 1.5 wt % or more, 2 wt % or more, 2.5 wt % or more, 3 wt % or more, 3.5 wt % or more, 4 wt % or more, 4.5 wt % or more, 5 wt % or more, 10 wt % or more, 15 wt % or more, 20 wt % or more, 25 wt % or more, 30 wt % or more, 35 wt % or more, or 40 wt % or more. The weight percent ratio of the aldehyde or ketone monomer of the first stage polymer to the aldehyde or ketone monomer of the second stage polymer is from 1:10 to 1:0.5 based on the total monomer weight of the corresponding stage.

[0038] The amount of adipic acid dihydrazide can be 0.1 wt % or more, 0.2 wt % or more, 0.3 wt % or more, 0.4 wt % or more, 0.5 wt % or more, 0.6 wt % or more, 0.7 wt % or more, 0.8 wt % or more, 0.9 wt % or more, 1 wt % or more, 1.5 wt % or more, 2 wt % or more, 2.5 wt % or more, 3 wt % or more, 5 wt % or more, or 10 wt % or more.

[0039] The ratio of the keto group in DAAM or diacetone (meth) acrylamide to the hydrazide group in the polyhydrazide varies from 1:0.4 equivalents to 1:1.5 equivalents (e.g., 1:0.5 equivalents to 1:1.5 equivalents, 1:0.6 equivalents to 1:2 equivalents, 1:0.7 equivalents to 1:1 equivalents, 1:0.8 equivalents to 1:1 equivalents, 1:0.9 equivalents to 1:1 equivalents). For example, the ratio of keto groups to polyhydrazide can be 1:0.4, 1:0.45, 1:0.5, 1:0.55, 1:0.6, 1:0.65, 1:0.7, 1:0.75, 1:0.8, 1:0.85, 1:0.9, 1:0.95, 1:1, 1:1.05, 1:1.1, 1:1.15, 1:1.2, 1:1.25, 1:1.3, 1:1.35, 1:1.4, 1:45 or 1:1.5.

[0040] The first stage copolymer and the second stage copolymer may also be derived from ethylenically unsaturated monomers. Exemplary ethylenically unsaturated monomers include (meth)acrylate monomers, vinyl aromatic monomers (e.g., styrene), ethylenically unsaturated aliphatic monomers (e.g., butadiene), vinyl ester monomers (e.g., vinyl acetate), and combinations thereof.

[0041] In some embodiments, the first stage copolymer may include an acrylic copolymer. Acrylic copolymers include copolymers derived from one or more (meth)acrylate monomers. Acrylic copolymers may be pure acrylic polymers (i.e., copolymers derived primarily from (meth)acrylate monomers), styrene-acrylic polymers (i.e., copolymers derived from styrene and one or more (meth)acrylate monomers), or vinyl-acrylic polymers (i.e., copolymers derived from one or more vinyl ester monomers and one or more (meth)acrylate monomers).

[0042] The first stage copolymer can be derived from one or more phosphorus-containing monomers. Suitable phosphorus-containing monomers are known in the art and include dihydrogen phosphates of alcohols (where the alcohol contains a polymerizable vinyl or alkenyl group), allyl phosphates, alkyl (meth) phosphates (such as 2-phosphoethyl (meth) acrylate (PEM), 2-phosphopropyl (meth) acrylate, 3-phosphopropyl (meth) acrylate, and butyl (meth) phosphate), 3-phospho-2-hydroxypropyl (meth) acrylate, monophosphates or diphosphates of bis(hydroxymethyl) fumarate or itaconate; phosphates of hydroxyalkyl (meth) acrylates, 2-hydroxyethyl (meth) acrylate, 3-hydroxypropyl (meth) acrylate, ethylene oxide condensates of (meth) acrylates,

[0043] [H2C=C(R)COO(CH2CH2O) n ] y P(O)(OH)z and similar propylene oxide and butylene oxide condensates, wherein n is an integer in the range of 1 to 50, y+z=3 and y=1 or 2, z=1 or 2; R=H or CH3; crotonate phosphate alkyl esters, maleate phosphate alkyl esters, fumarate phosphate alkyl esters, (meth) acrylate dialkyl phosphate esters, crotonate dialkyl phosphate esters, vinylphosphonic acid, allylphosphonic acid, 2-acrylamido-2-methylpropanephosphinic acid, α-phosphonic acid styrene, 2-methacrylamido-2-methylpropanephosphinic acid, (meth) acrylate (hydroxy) phosphinyl alkyl esters, methacrylate (hydroxy) phosphinyl methyl esters, and combinations thereof. The phosphate esters of the (meth) hydroxyalkyl esters may have the general formula [H2C═C(R)COOCnH2nO] y P(O)(OH) z , wherein n is 2, 3 or 4; y+z=3 and y=1 or 2, z=1 or 2; R is H or CH3. Examples of unsaturated monomers containing phosphate esters are PAM 4000, PAM 200, PAM 100, and PAM 600. Alkali metal or alkaline earth metal ion or ammonia neutralized salts of the above acids and combinations thereof may also be used.

[0044] The first stage copolymer can be derived from 0.1 wt % to 5 wt % of one or more phosphorus-containing monomers, such as about 0.1 wt % or greater, about 0.2 wt % or greater, about 0.5 wt % or greater, about 0.7 wt % or greater, about 1 wt % or greater, about 2 wt % or less, about 3 wt % or less, about 4 wt % or less, about 5 wt % or less, or any value encompassed by these endpoints, such as about 0.1 wt % to about 0.2 wt %, about 0.3 wt % to about 4 wt %, or about 0.5 wt % to about 2 wt %, based on the total weight of the monomers used to form the first copolymer.

[0045] The first copolymer may be derived from an amount of one or more phosphorus-containing monomers ranging from any of the above minimum percentages to any of the above maximum percentages. For example, based on the total weight of the monomers used to form the first copolymer, the first copolymer may be derived from 0.1 wt % to 5 wt % of one or more phosphorus-containing monomers (e.g., 0.1 wt % to 2.5 wt % of one or more phosphorus-containing monomers). In certain embodiments, the first copolymer is derived from 0.1 wt % to 5 wt % (e.g., 0.1 wt % to 3 wt %, 0.1 wt % to 2.5 wt %, or 0.1 wt % to 1.5 wt %) of 2-phosphoethyl methacrylate and a compound of the general formula [H2C=C(R)COOCH2CH2O]yP(O)(OH) zPhosphoric acid di(ethyl methacrylate), wherein y+z=3 and y=1 or 2, z=1 or 2; R=H or CH3.

[0046] The first copolymer may be derived from an amount of one or more phosphorus-containing monomers ranging from any of the above minimum percentages to any of the above maximum percentages. For example, based on the total weight of the monomers used to form the first copolymer, the first copolymer may be derived from greater than 0 wt % to 5 wt % of one or more phosphorus-containing monomers (e.g., greater than 0 wt % to 2.5 wt % of one or more phosphorus-containing monomers). In certain embodiments, the first copolymer is derived from greater than 0 wt % to 5 wt % (e.g., greater than 0 wt % to 3 wt %, greater than 0 wt % to 2.5 wt %, or greater than 0 wt % to 1.5 wt %) of 2-phosphoethyl methacrylate (PEM).

[0047] The first stage copolymer may be derived from one or more additional self-crosslinking monomers. Suitable additional self-crosslinking monomers are known in the art and include acetoacetoxyalkyl (meth)acrylates, such as acetoacetoxyethyl (meth)acrylate (AAEM), acetoacetoxypropyl (meth)acrylate, acetoacetoxybutyl (meth)acrylate, and 2,3-di(acetoacetoxy)propyl (meth)acrylate; allyl acetoacetate; vinyl acetoacetate; and combinations thereof.

[0048] The first stage polymer may be derived from one or more carboxylic acid-containing monomers, based on the total weight of the monomers. Suitable carboxylic acid-containing monomers are known in the art and include α,β-monoethylenically unsaturated monocarboxylic acids and dicarboxylic acids, such as acrylic acid, methacrylic acid, itaconic acid, crotonic acid, maleic acid, fumaric acid, dimethacrylic acid, ethacrylic acid, allyl acetic acid, vinyl acetic acid, mesaconic acid, methylenemalonic acid, citraconic acid, and combinations thereof.

[0049] The first stage copolymer can be derived from one or more acrylate or methacrylate monomers. Exemplary acrylate and methacrylate monomers include, but are not limited to, methyl acrylate, methyl methacrylate, ethyl acrylate, ethyl methacrylate, n-butyl acrylate, butyl methacrylate, 2-ethylhexyl acrylate, 2-ethylhexyl methacrylate, isobutyl (meth)acrylate, n-hexyl (meth)acrylate, n-heptyl (meth)acrylate, 2-methylheptyl (meth)acrylate, octyl (meth)acrylate, isooctyl (meth)acrylate, n-nonyl (meth)acrylate, isononyl (meth)acrylate, n-decyl (meth)acrylate, isodecyl (meth)acrylate, dodecyl (meth)acrylate, lauryl (meth)acrylate, tridecyl (meth)acrylate, stearyl (meth)acrylate, glycidyl (meth)acrylate, alkyl crotonate, vinyl acetate, di-n-butyl maleate , dioctyl maleate, hydroxyethyl (meth)acrylate, allyl (meth)acrylate, tetrahydrofurfuryl (meth)acrylate, cyclohexyl (meth)acrylate, 2-ethoxyethyl (meth)acrylate, 2-methoxy (meth)acrylate, 2-(2-ethoxyethoxy)ethyl (meth)acrylate, 2-propylheptyl (meth)acrylate, 2-phenoxyethyl (meth)acrylate, isobornyl (meth)acrylate, caprolactone (meth)acrylate, polypropylene glycol mono(meth)acrylate, polyethylene glycol (meth)acrylate, benzyl (meth)acrylate, hydroxypropyl (meth)acrylate, methyl polyethylene glycol (meth)acrylate, 3,4-epoxycyclohexyl methyl (meth)acrylate, 1,6-hexanediol di(meth)acrylate, 1,4-butanediol di(meth)acrylate, and combinations thereof. In some embodiments, the first copolymer is derived from one or more (meth)acrylate monomers selected from methyl methacrylate, n-butyl acrylate, 2-ethylhexyl acrylate, and combinations thereof. In some embodiments, the first copolymer is derived from methyl methacrylate and butyl acrylate.

[0050] The first copolymer can be derived from one or more vinyl aromatic compounds. Suitable vinyl aromatic compounds include styrene, α- and p-methylstyrene, α-butylstyrene, 4-n-butylstyrene, 4-n-decylstyrene, vinyl toluene and combinations thereof. Vinyl esters with carboxylic acids containing up to 20 carbon atoms include, for example, vinyl laurate, vinyl stearate, vinyl propionate, tert-carbonic acid vinyl ester, vinyl acetate and combinations thereof. Vinyl halides can include ethylenically unsaturated compounds substituted by chlorine, fluorine or bromine, such as vinyl chloride and vinylidene chloride. Vinyl ethers can include, for example, vinyl ethers of alcohols containing 1 to 4 carbon atoms, such as vinyl methyl ether or vinyl isobutyl ether. Aliphatic hydrocarbons with 2 to 8 carbon atoms and one or two double bonds can include, for example, hydrocarbons with 4 to 8 carbon atoms and two olefin double bonds, such as butadiene, isoprene and chloroprene. Silane-containing monomers may include, for example, vinyl silanes such as vinyl trimethoxysilane, vinyl triethoxysilane (VTEO), vinyl tris(2-methoxyethoxysilane), and vinyl triisopropoxysilane; and (meth)acryloyl alkoxysilanes such as (meth)acryloxypropyl trimethoxysilane, γ-(meth)acryloxypropyl trimethoxysilane, and γ-(meth)acryloxypropyl triethoxysilane.

[0051] In some embodiments, monomers for the first stage copolymer include monomers that promote wet adhesion, such as ureido (cyclic ethylene urea) functional monomers and diketone functional monomers. Specific examples include ureido methacrylate (UMA) and acetoacetoxyethyl methacrylate.

[0052] The second-stage polymer can be a homopolymer derived from a single ethylenically unsaturated monomer or a copolymer derived from an ethylenically unsaturated monomer. In some embodiments, the second-stage polymer includes an acrylic polymer. The acrylic polymer includes a polymer derived from one or more (meth) acrylate monomers. The acrylic polymer can be a pure acrylic polymer (i.e., a polymer derived only from (meth) acrylate monomers), a styrene-acrylic polymer (i.e., a copolymer derived from styrene and one or more (meth) acrylate monomers) or a vinyl-acrylic polymer (i.e., a copolymer derived from one or more vinyl ester monomers and one or more (meth) acrylate monomers).

[0053] The second stage copolymer may also be derived from ethylenically unsaturated monomers. Exemplary ethylenically unsaturated monomers include (meth)acrylate monomers, vinyl aromatic monomers (e.g., styrene), ethylenically unsaturated aliphatic monomers (e.g., butadiene), vinyl ester monomers (e.g., vinyl acetate), and combinations thereof.

[0054] In some embodiments, the second stage copolymer may include an acrylic copolymer. Acrylic copolymers include copolymers derived from one or more (meth)acrylate monomers. Acrylic copolymers may be pure acrylic polymers (i.e., copolymers derived primarily from (meth)acrylate monomers), styrene-acrylic polymers (i.e., copolymers derived from styrene and one or more (meth)acrylate monomers), or vinyl-acrylic polymers (i.e., copolymers derived from one or more vinyl ester monomers and one or more (meth)acrylate monomers).

[0055] The second stage copolymer may be derived from one or more phosphorus-containing monomers. Suitable phosphorus-containing monomers are known in the art and include dihydrogen phosphates of alcohols (where the alcohol contains a polymerizable vinyl or alkenyl group), allyl phosphates, alkyl (meth) phosphates (such as 2-ethyl (meth) acrylate (PEM), 2-propyl (meth) acrylate, 3-propyl (meth) acrylate, and butyl (meth) acrylate), 3-phospho-2-hydroxypropyl (meth) acrylate, monophosphates or diphosphates of bis (hydroxymethyl) fumarate or itaconate; phosphates of hydroxyalkyl (meth) acrylates, 2-hydroxyethyl (meth) acrylate, 3-hydroxypropyl (meth) acrylate, ethylene oxide condensates of (meth) acrylates, [H2C=C(R)COO(CH2CH2O) n ] y P(O)(OH) z and similar propylene oxide and butylene oxide condensates, wherein n is an integer in the range of 1 to 50, y+z=3 and y=1 or 2, z=1 or 2; R=H or CH3; crotonate phosphate alkyl esters, maleate phosphate alkyl esters, fumarate phosphate alkyl esters, (meth) acrylate dialkyl phosphate esters, crotonate dialkyl phosphate esters, vinylphosphonic acid, allylphosphonic acid, 2-acrylamido-2-methylpropanephosphinic acid, α-phosphonic acid styrene, 2-methacrylamido-2-methylpropanephosphinic acid, (meth) acrylate (hydroxy) phosphinyl alkyl esters, methacrylate (hydroxy) phosphinyl methyl esters, and combinations thereof. The phosphate esters of the (meth) hydroxyalkyl esters may have the general formula [H2C═C(R)COOCnH2nO] y P(O)(OH) z , wherein n is 2, 3 or 4; y+z=3 and y=1 or 2, z=1 or 2; R is H or CH3. Examples of unsaturated monomers containing phosphate esters are PAM 4000, PAM 200, PAM 100, and PAM 600. Alkali or alkaline earth metal ion or ammonia neutralized salts of the above acids and combinations thereof may also be used.

[0056] The second stage copolymer can optionally be derived from 0.0 wt % to 5 wt % of one or more phosphorus-containing monomers, such as about 0.1 wt % or greater, about 0.2 wt % or greater, about 0.5 wt % or greater, about 0.7 wt % or greater, about 1 wt % or greater, about 2 wt % or less, about 3 wt % or less, about 4 wt % or less, about 5 wt % or less, or any value encompassed by these endpoints, such as about 0.0 wt % to about 0.2 wt %, about 0.3 wt % to about 4 wt %, or about 0.5 wt % to about 2 wt %, based on the total weight of the monomers used to form the second stage copolymer.

[0057] The second stage copolymer may be derived from an amount of one or more phosphorus-containing monomers ranging from any of the above minimum percentages to any of the above maximum percentages. For example, the second stage copolymer may be derived from 0.0 wt % to 5 wt % of one or more phosphorus-containing monomers (e.g., 0.0 wt % to 2.5 wt % of one or more phosphorus-containing monomers), based on the total weight of the monomers used to form the second stage copolymer. In certain embodiments, the second stage copolymer is derived from 0.1 wt % to 5 wt % (e.g., 0.1 wt % to 3 wt %, 0.1 wt % to 2.5 wt %, or 0.1 wt % to 1.5 wt %) of 2-phosphoethyl methacrylate and a ester of the general formula [H2C=C(R)COOCH2CH2O]yP(O)(OH) z Phosphoric acid di(ethyl methacrylate), wherein y+z=3 and y=1 or 2, z=1 or 2; R=H or CH3.

[0058] The second stage copolymer may be derived from an amount of one or more phosphorus-containing monomers ranging from any of the above minimum percentages to any of the above maximum percentages. For example, based on the total weight of the monomers used to form the second copolymer, the second copolymer may be derived from greater than 0 wt % to 5 wt % of one or more phosphorus-containing monomers (e.g., greater than 0 wt % to 2.5 wt % of one or more phosphorus-containing monomers). In certain embodiments, the second copolymer is derived from greater than 0 wt % to 5 wt % (e.g., greater than 0 wt % to 3 wt %, greater than 0 wt % to 2.5 wt %, or greater than 0 wt % to 1.5 wt %) of 2-phosphoethyl methacrylate (PEM).

[0059] The second stage copolymer can be derived from one or more self-crosslinking monomers. Suitable self-crosslinking monomers are known in the art and include acetoacetoxyalkyl (meth)acrylates, such as acetoacetoxyethyl (meth)acrylate (AAEM), acetoacetoxypropyl (meth)acrylate, acetoacetoxybutyl (meth)acrylate, and 2,3-bis(acetoacetoxy)propyl (meth)acrylate; allyl acetoacetate; vinyl acetoacetate; and combinations thereof.

[0060] The second stage polymer may be derived from one or more carboxylic acid-containing monomers, based on the total weight of the monomers. Suitable carboxylic acid-containing monomers are known in the art and include α,β-monoethylenically unsaturated monocarboxylic acids and dicarboxylic acids, such as acrylic acid, methacrylic acid, itaconic acid, crotonic acid, maleic acid, fumaric acid, dimethacrylic acid, ethacrylic acid, allyl acetic acid, vinyl acetic acid, mesaconic acid, methylenemalonic acid, citraconic acid, and combinations thereof.

[0061] The second stage copolymer can be derived from one or more acrylate or methacrylate monomers. Exemplary acrylate and methacrylate monomers include, but are not limited to, methyl acrylate, methyl methacrylate, ethyl acrylate, ethyl methacrylate, n-butyl acrylate, butyl methacrylate, 2-ethylhexyl acrylate, 2-ethylhexyl methacrylate, isobutyl (meth)acrylate, n-hexyl (meth)acrylate, n-heptyl (meth)acrylate, 2-methylheptyl (meth)acrylate, octyl (meth)acrylate, isooctyl (meth)acrylate, n-nonyl (meth)acrylate, isononyl (meth)acrylate, n-decyl (meth)acrylate, isodecyl (meth)acrylate, dodecyl (meth)acrylate, lauryl (meth)acrylate, tridecyl (meth)acrylate, stearyl (meth)acrylate, glycidyl (meth)acrylate, alkyl crotonate, vinyl acetate, di-n-butyl maleate , dioctyl maleate, hydroxyethyl (meth)acrylate, allyl (meth)acrylate, tetrahydrofurfuryl (meth)acrylate, cyclohexyl (meth)acrylate, 2-ethoxyethyl (meth)acrylate, 2-methoxy (meth)acrylate, 2-(2-ethoxyethoxy)ethyl (meth)acrylate, 2-propylheptyl (meth)acrylate, 2-phenoxyethyl (meth)acrylate, isobornyl (meth)acrylate, caprolactone (meth)acrylate, polypropylene glycol mono(meth)acrylate, polyethylene glycol (meth)acrylate, benzyl (meth)acrylate, hydroxypropyl (meth)acrylate, methyl polyethylene glycol (meth)acrylate, 3,4-epoxycyclohexyl methyl (meth)acrylate, 1,6-hexanediol di(meth)acrylate, 1,4-butanediol di(meth)acrylate, and combinations thereof. In some embodiments, the second copolymer is derived from one or more (meth)acrylate monomers selected from the group consisting of methyl methacrylate, n-butyl acrylate, 2-ethylhexyl acrylate, and combinations thereof. In some embodiments, the second copolymer is derived from methyl methacrylate and butyl acrylate.

[0062] The second copolymer can be derived from one or more vinyl aromatic compounds. Suitable vinyl aromatic compounds include styrene, α- and p-methylstyrene, α-butylstyrene, 4-n-butylstyrene, 4-n-decylstyrene, vinyl toluene and combinations thereof. Vinyl esters with carboxylic acids containing up to 20 carbon atoms include, for example, vinyl laurate, vinyl stearate, vinyl propionate, tert-carbonic acid vinyl ester, vinyl acetate and combinations thereof. Vinyl halides can include ethylenically unsaturated compounds substituted by chlorine, fluorine or bromine, such as vinyl chloride and vinylidene chloride. Vinyl ethers can include, for example, vinyl ethers of alcohols containing 1 to 4 carbon atoms, such as vinyl methyl ether or vinyl isobutyl ether. Aliphatic hydrocarbons with 2 to 8 carbon atoms and one or two double bonds can include, for example, hydrocarbons with 4 to 8 carbon atoms and two olefin double bonds, such as butadiene, isoprene and chloroprene. Silane-containing monomers may include, for example, vinyl silanes such as vinyl trimethoxysilane, vinyl triethoxysilane (VTEO), vinyl tris(2-methoxyethoxysilane), and vinyl triisopropoxysilane; and (meth)acryloyl alkoxysilanes such as (meth)acryloxypropyl trimethoxysilane, γ-(meth)acryloxypropyl trimethoxysilane, and γ-(meth)acryloxypropyl triethoxysilane.

[0063] In some embodiments, monomers for the second stage copolymer include monomers that promote wet adhesion, such as ureido (cyclic ethylene urea) functional monomers and diketone functional monomers. Specific examples include ureido methacrylate (UMA) and acetoacetoxyethyl methacrylate.

[0064] Also provided is an aqueous composition comprising one or more of the above-mentioned multistage self-crosslinking polymers. The aqueous composition may also include one or more additives, including pigments, fillers, dispersants, coalescing agents, pH regulators, plasticizers, defoamers, surfactants, thickeners, biocides, cosolvents and combinations thereof. The selection of additives in the composition will be affected by many factors, including the properties of the multistage polymers (or multilayer particles) dispersed in the aqueous composition and the intended use of the composition. In some cases, the composition may be, for example, a coating composition, such as a paint, a primer or a paint and a primer in one formulation.

[0065] Examples of suitable pigments include metal oxides such as titanium dioxide, zinc oxide, iron oxide, or combinations thereof. In certain embodiments, the composition comprises titanium dioxide pigment. Examples of commercial titanium dioxide pigments are 2101, 2310 (available from Kronos WorldWide, Inc. (Cranbury, NJ)), R-900 (available from DuPont, Wilmington, Del.) or AT1 (commercially available from Millennium Inorganic Chemicals). Titanium dioxide is also available in the form of a concentrated dispersion. An example of a titanium dioxide dispersion is 4311, also available from Kronos WorldWide, Inc.

[0066] Examples of suitable fillers include calcium carbonate, nepheline syenite (25% nepheline, 55% albite and 20% potassium feldspar), feldspar (aluminum silicate), diatomaceous earth, calcined diatomaceous earth, talc (hydrated magnesium silicate), aluminosilicate, silica (silicon dioxide), alumina (aluminum oxide), clay (hydrated aluminum silicate), kaolin (kaolinite, hydrated aluminum silicate), mica (hydrous potassium aluminum silicate), pyrophyllite (aluminum hydroxide silicate), perlite, barite (barium sulfate), wollastonite (calcium metasilicate), and combinations thereof. In certain embodiments, the composition comprises a calcium carbonate filler.

[0067] Examples of suitable dispersants are polyacid dispersants and hydrophobic copolymer dispersants. Polyacid dispersants are typically polycarboxylic acids, such as polyacrylic acid or polymethacrylic acid, which are partially or completely present in the form of their ammonium salts, alkali metal salts, alkaline earth metal salts, ammonium salts or lower alkyl quaternary ammonium salts. Hydrophobic copolymer dispersants include copolymers of acrylic acid, methacrylic acid or maleic acid with hydrophobic monomers. In certain embodiments, the composition comprises a polyacrylic acid type dispersant, such as commercially available from BASF SE CX-4230.

[0068] Suitable coalescing agents that aid in film formation during drying include ethylene glycol monomethyl ether, ethylene glycol monobutyl ether, ethylene glycol monoethyl ether acetate, ethylene glycol monobutyl ether acetate, diethylene glycol monobutyl ether, diethylene glycol monoethyl ether acetate, dipropylene glycol monomethyl ether, 2,2,4-trimethyl-1,3-pentanediol monoisobutyrate, 2-ethylhexyl benzoate, and combinations thereof. Suitable coalescing agents also include ETHYLENE GLYCOL MONOMETHYL ETHER, available from BASF Inc. A series of low VOC coalescing agents.

[0069] Examples of suitable thickeners include hydrophobically modified ethylene oxide urethane (HEUR) polymers, hydrophobically modified alkali-soluble emulsion (HASE) polymers, hydrophobically modified hydroxyethyl cellulose (HMHEC), hydrophobically modified polyacrylamide, and combinations thereof. HEUR polymers are linear reaction products of diisocyanates and polyethylene oxides terminated with hydrophobic hydrocarbon groups. HASE polymers are homopolymers of (meth)acrylic acid, or copolymers of (meth)acrylic acid, (meth)acrylates, or maleic acid modified with hydrophobic vinyl monomers. HMHEC comprises hydroxyethyl cellulose modified with a hydrophobic alkyl chain. Hydrophobically modified polyacrylamide comprises copolymers of acrylamide and acrylamide (N-alkyl acrylamide) modified with a hydrophobic alkyl chain. In certain embodiments, the coating composition comprises a hydrophobically modified hydroxyethyl cellulose thickener.

[0070] Examples of suitable pH adjusters include amino alcohols, monoethanolamine (MEA), diethanolamine (DEA), 2-(2-aminoethoxy)ethanol, diisopropanolamine (DIPA), 1-amino-2-propanol (AMP), ammonia, and combinations thereof.

[0071] Defoamers are used to minimize foaming during mixing and / or application of the coating composition. Suitable defoamers include silicone oil defoamers such as polysiloxanes, polydimethylsiloxanes, polyether-modified polysiloxanes, mineral oil defoamers, hyperbranched polymers, and combinations thereof. Exemplary defoamers include BASF Inc.'s and EFKA series defoamers, available from BYK USA Inc. (Wallingford, CT) series of defoamers, available from Evonik Industries (Hopewell, VA) series of defoamers and the HYDROGEN(R) series available from Ashland Inc. (Covington, KY) Series of defoamers.

[0072] Suitable surfactants include nonionic surfactants and anionic surfactants. Examples of nonionic surfactants are alkylphenoxypolyethoxyethanols having an alkyl group of about 7 to about 18 carbon atoms and having about 6 to about 60 ethylene oxide units; ethylene oxide derivatives of long chain carboxylic acids; similar ethylene oxide condensates of long chain alcohols, and combinations thereof. Exemplary anionic surfactants include: ammonium, alkali metal, alkaline earth metal, and lower alkyl quaternary ammonium salts of sulfosuccinates; higher fatty alcohol sulfates; aryl sulfonates; alkyl sulfonates; alkyl aryl sulfonates; and combinations thereof. In certain embodiments, the composition comprises a nonionic alkyl polyethylene glycol surfactant such as Hydropalat WE 3320, commercially available from BASF SE, TDA 8 or AT-18. In certain embodiments, the composition comprises an anionic alkyl ether sulfate surfactant, such as commercially available from BASF SE FES 77. In certain embodiments, the compositions include an anionic diphenyl oxide disulfonate surfactant, such as commercially available from Pilot Chemical. DB-45. In some embodiments, the composition is substantially free of (i.e., the composition comprises 0.1 wt % or less) sulfate surfactants. In some embodiments, the composition is substantially free of (i.e., the composition comprises 0.1 wt % or less) sulfonate surfactants. In some embodiments, the composition is substantially free of (i.e., the composition comprises 0.1 wt % or less) sulfate surfactants and sulfonate surfactants.

[0073] Suitable biocides may be incorporated to inhibit the growth of bacteria and other microorganisms in the coating composition during storage. Exemplary biocides include 2-[(hydroxymethyl)amino]ethanol, 2-[(hydroxymethyl)amino]2-methyl-1-propanol, o-phenylphenol, sodium salt, 1,2-benzisothiazolin-3-one, 2-methyl-4-isothiazolin-3-one (MIT), 5-chloro-2-methyl-4-isothiazolin-3-one (CIT), 2-octyl-4-isothiazolin-3-one (OTT), 4,5-dichloro-2-n-octyl-3-isothiazolone, and their acceptable salts and combinations thereof. Suitable biocides also include mildew inhibitors that inhibit the growth of mold and its spores in the coating. Examples of mildewcides include 2-(thiocyanatomethylthio)benzothiazole, 3-iodo-2-propynylbutyl carbamate, 2,4,5,6-tetrachloroisophthalonitrile, 2-(4-thiazolyl)benzimidazole, 2-N-octyl 4-isothiazolin-3-one, diiodomethyl-p-tolylsulfone, and acceptable salts thereof and combinations thereof. In certain embodiments, the coating composition contains 1,2-benzisothiazolin-3-one or a salt thereof. This type of biocide includes commercially available biocides from Arch Chemicals, Inc (Atlanta, Ga.) BD20.

[0074] Exemplary co-solvents and plasticizers include ethylene glycol, propylene glycol, diethylene glycol, and combinations thereof.

[0075] Other suitable additives that may be optionally incorporated into the composition include rheology modifiers, wetting and dispersing agents, leveling agents, conductivity additives, adhesion promoters, anti-blocking agents, anti-cratering and anti-wrinkling agents, antifreeze agents, corrosion inhibitors, antistatic agents, flame retardants and swelling aids, dyes, fluorescent brighteners and fluorescent additives, UV absorbers and light stabilizers, chelating agents, cleaning additives, crosslinking agents, matting agents, flocculants, wetting agents, biocides, lubricants, odorants, oils, waxes and slip aids, soil repellents, antifouling agents, and combinations thereof.

[0076] The coating composition can be applied to the surface by any suitable coating technique (comprising spraying, roller coating, brushing or spreading). Depending on the needs of the specific application, the coating composition can be applied with a single coating or with multiple continuous coatings (e.g., with two coatings or with three coatings). Typically, the coating composition is dried under ambient conditions. However, in certain embodiments, the coating composition can be dried, for example, by heating and / or by circulating air on the coating.

[0077] The coating composition can be applied to various surfaces, including but not limited to metal, asphalt, concrete, stone, ceramic, wood, plastic, polyurethane foam, glass, wallboard coverings (e.g., drywall, cement board, etc.), and combinations thereof. The coating composition can be applied to an inner surface or an outer surface. In certain embodiments, the surface is a building surface, such as a roof, a wall, a floor, or a combination thereof. The building surface can be located above ground, underground, or a combination thereof.

[0078] Also provided is a coating formed by the coating composition described herein. Typically, the coating is formed by applying the coating composition described herein to a surface and allowing the coating to dry to form a coating. The coating thickness may vary depending on the application of the coating.

[0079] Also provided is a method for preparing the above-mentioned multistage polymers and multilayer particles. The above-mentioned multistage polymers and multilayer particles can be prepared by heterogeneous polymerization techniques (including, for example, free radical emulsion polymerization, suspension polymerization, and microemulsion polymerization). In some examples, the multistage polymer is prepared by polymerizing the monomers using free radical emulsion polymerization. The emulsion polymerization temperature can be between 10°C and 130°C (for example, from 50°C to 90°C). The polymerization medium can contain water alone or a mixture of water and a water-miscible liquid, such as methanol, ethanol, or tetrahydrofuran. In some embodiments, the polymerization medium does not contain an organic solvent and contains only water.

[0080] Emulsion polymerization can be carried out in a batch process, a semi-batch process or in a continuous process. In some embodiments, a portion of the monomers can be heated to the polymerization temperature and partially polymerized, and then the remainder of the monomer batch can be fed to the polymerization zone continuously, stepwise or with a superimposed concentration gradient.

[0081] Emulsion polymerization can be carried out using a variety of auxiliary agents, including water-soluble initiators and regulators. Examples of water-soluble initiators for emulsion polymerization are ammonium salts and alkali metal salts of peroxodisulfuric acid (e.g., sodium peroxodisulfate), hydrogen peroxide or organic peroxides, such as tert-butyl hydroperoxide. Reduction-oxidation (redox) initiator systems are also suitable as initiators for emulsion polymerization. Redox initiator systems are composed of at least one, usually inorganic, reducing agent, and an organic or inorganic oxidizing agent. For example, the oxidizing component includes the initiator specified above for emulsion polymerization. For example, the reducing component is an alkali metal salt of sulfurous acid (such as sodium sulfite, sodium bisulfite), an alkali metal salt of disulfurous acid (such as sodium bisulfite), a bisulfite addition compound with aliphatic aldehydes and ketones (such as acetone bisulfite), or a reducing agent (such as hydroxymethanesulfinic acid and its salts) or ascorbic acid. Redox initiator systems can be used together with soluble metal compounds, and their metal components can exist in multiple valence states. Typical redox initiator systems include, for example, ascorbic acid / iron sulfate (II) / sodium peroxodisulfate, tert-butyl hydroperoxide / sodium metabisulfite, tert-butyl hydroperoxide / sodium hydroxymethanesulfinic acid or tert-butyl hydroperoxide / ascorbic acid. A single component, such as a reducing component, may also be a mixture, exemplified by a mixture of the sodium salt of hydroxymethanesulfinic acid and sodium metabisulfite. The compound is typically used in the form of an aqueous solution, wherein a lower concentration is determined by the amount of water acceptable in the dispersion, while a higher concentration is determined by the solubility of the corresponding compound in water. Based on the solution, the concentration may be 0.1% to 30% by weight, 0.5% to 20% by weight or 1.0% to 10% by weight. Based on the monomer to be polymerized, the amount of initiator is typically 0.1% to 10% by weight or 0.2% to 5% by weight. Two or more different initiators may also be used in emulsion polymerization. In order to remove residual monomers, an initiator may be added after the end of the emulsion polymerization.

[0082] In polymerization, a molecular weight regulator or chain transfer agent can be used, for example, based on 100 parts by weight of the monomer to be polymerized, in an amount of 0 to 0.8 parts by weight to reduce the molecular weight of the copolymer. Suitable examples include compounds with thiol groups, such as tert-butyl mercaptan, thioglycolic acid ethyl acrylate, mercaptoethanol, mercaptopropyl trimethoxysilane and tert-dodecyl mercaptan. In addition, a regulator without a thiol group, such as terpinolene, can be used. In some embodiments, the emulsion polymer is prepared in the presence of at least one molecular weight regulator greater than 0% to 0.5% by weight based on the amount of monomer. In some embodiments, the emulsion polymer is prepared in the presence of a molecular weight regulator less than less than 0.3% by weight or less than 0.2% by weight (e.g., 0.10% to 0.15% by weight).

[0083] Dispersants, such as surfactants, can also be added during the polymerization process to help keep the monomers dispersed in aqueous media. For example, the polymerization can include less than 3 % by weight or less than 1 % by weight of surfactant. In some embodiments, the polymerization reaction is substantially free of surfactants and can include less than 0.05 % by weight or less than one or more surfactants of 0.01 % by weight. In other embodiments, the first emulsion polymerization step and / or the second polymerization step also include aryl or alkyl phosphate surfactants. These phosphate surfactants can include alkoxylated alkyl or aryl surfactants. (For example, tristyrylphenol alkoxylated phosphate surfactants).

[0084] Anionic and nonionic surfactants may be used during the polymerization process. Suitable surfactants include ethoxylated C8-C 36 or C 12 -C 18 Fatty alcohols, ethoxylated mono-, di- and tri-C4-C 12 or C4-C9 alkylphenol, alkali metal salt of dialkyl sulfosuccinate, C8-C 12 Alkali metal and ammonium salts of alkyl sulfates, C 12 -C 18 Alkali metal and ammonium salts of alkylsulfonic acids and C9-C 18 Alkali metal and ammonium salts of alkylarylsulfonic acids.

[0085] By way of non-limiting illustration, examples of certain embodiments of the present disclosure are given below.

[0086] Example

[0087] The following examples are presented to provide those of ordinary skill in the art with a complete disclosure and description of how to prepare and evaluate the compositions and / or methods claimed herein, and are intended to be purely exemplary and not intended to limit the scope of the present disclosure. Unless otherwise indicated, parts are parts by weight, temperature units are ° C or are ambient temperature, and pressures are at or near atmospheric pressure.

[0088] Examples 1 to 4: Preparation of self-crosslinking polymer latex

[0089] A polymerization vessel equipped with a metering device and temperature regulation is initially charged under a nitrogen atmosphere at 20° C. to 25° C. (room temperature). This initial charge is heated to 85° C. with stirring. When the set temperature is reached, 7% of feed 1 is added and the mixture is stirred for 5 minutes. Then feed 1 and feed 2 are started; feed 1 is metered in over 3.3 hours and feed 2 is metered in over 2.55 hours. Ten minutes after the end of feed 2, feed 3 is added over 30 minutes. Ten minutes after the end of the feed, the temperature is lowered to 80° C. and feed 4 and then feed 5 are added over 15 minutes. Then feed 6 and feed 7 are metered in parallel over 60 minutes. 12 minutes after the end of these feeds, the batch is cooled to below 40° C. Then feed 8 is added over 5 minutes and then feed 9 over 10 minutes. The batch is mixed for 5 minutes, the pH is adjusted to 8.5 using 19% aqueous ammonium hydroxide solution and filtered. % solids, pH, viscosity and particle size were measured.

[0090] Representative examples of polymer dispersions prepared using Procedure 1 are provided in Table 1 below.

[0091] Table 1

[0092] Procedure 1: Polymer dispersions prepared in Examples 1 to 4 were used.

[0093]

[0094]

[0095] *-TSPAP-Ammonium salt of tristyrylphenol alkoxylated phosphate surfactant (24% aqueous solution)

[0096] Comparative Example 1: Preparation of Control Polymer Latex

[0097] A multi-stage polymer latex comprising a first stage derived from butyl acrylate, methyl methacrylate, itaconic acid, acetoacetoxyethyl methacrylate (AAEM) and 2-phosphoethyl methacrylate (PEM) with a theoretical Tg of 12°C and a second stage derived from methyl methacrylate ("Polymer 1") with a theoretical Tg of 100°C was prepared by a continuous emulsion polymerization step as described below. A 3L glass container with 435g of deionized water and 46g of pre-polymerized seed latex was heated to 85°C. An initiator (sodium persulfate) was fed to the container during the polymerization of the first and second stages for 3.8 hours. 1149g of the first stage emulsion comprising the above monomer mixture, phosphate aromatic surfactant and nonionic surfactant was fed to the container over a period of 2.5 hours. Subsequently, 212g of the second stage emulsion comprising the above monomer mixture and phosphate aromatic surfactant was fed to the container. After the second stage was fully fed, the reaction was maintained at this temperature for 30 minutes while adding ammonium hydroxide and a defoamer. Next, the reaction temperature was lowered to 80°C and tert-butyl hydroperoxide and sodium metabisulfite were fed simultaneously to the reaction over a period of 1 hour. The reaction was then cooled to 40°C and the pH was adjusted with ammonium hydroxide. The biocide was then added to the reaction mixture. The final latex was filtered through a 150 mesh. Polymer 1 exhibited a Tg of 17°C, as determined by DSC using the method described in ASTM D3418-12e1 entitled "Standard Test Method for Transition Temperatures and Enthalts of Fusion and Crystallization of Polymers by Differential Scanning Calorimetry," which is incorporated herein by reference in its entirety.

[0098] Polymer 1 was then formulated into the standard semi-gloss white base formulation in Table 2.

[0099] Semi-gloss paint formulation using the polymers of Examples 1 to 4 and Comparative Example 1

[0100] A semi-gloss paint was formulated using the polymers of the present disclosure (Examples 1 to 4 above and Comparative Example 1). The paint also contained the components shown in Table 2 below.

[0101] Table 2

[0102] Paint formulation mass allowance

[0103]

[0104]

[0105] *-49 wt% solids dispersion in water.

[0106] The coatings prepared in Examples 1 to 4 and Comparative Example 1 were tested for gloss according to the ASTM D523 test method, and for scrub resistance according to the ASTM D2486-17 test method.

[0107] The coatings were also tested for scratch and abrasion resistance by scraping the surface with a plastic spoon, fork and black shoe sole. The plastic spoon and fork were dragged across the surface of the cured coating and visual ratings of the abrasion were collected. Figure 1 The pendulum swinging device shown in the figure scrapes the black sole across the surface of the cured coating. The test results are shown in Table 3 below.

[0108] Table 3

[0109] Gloss, wear resistance and scratch resistance of Examples 1 to 4 and Comparative Example 1 .

[0110] Example 1 Example 2 Example 3 Example 4 Comparative Example 1 luster 20° 14.1 13.2 9.8 12.9 7.4 60° 48.5 46.6 43.8 48.2 47.6 85° 79.9 77.2 79.4 82.1 85.6 Scratch resistance of plastic spoons* + + + + Comparison Plastic fork abrasion resistance* + + + + Comparison Pendulum swing wear resistance** + + + + Comparison Scrub resistance (% of control) 228 176 272 180 100% (control)

[0111] * - Visual rating of damage inflicted on the coating. + Indicates improved scratch and abrasion resistance compared to the control coating.

[0112] **-Using Kimwips purchased from Kimberly Clark TM A visual rating of the brightness of the black mark left on a painted surface after cleaning.

Claims

1. A polymer emulsion composition having a first stage and a second stage, the polymer emulsion composition comprising: Monomers containing ketone or aldehyde groups and Cross-linking agent containing polyhydrazide, The equivalent ratio of the ketone to the hydrazide functional group is in the range of 1:0.6 to 1:1.

5.

2. The polymer composition of claim 1, wherein the ketone-containing monomer comprises diacetone acrylamide.

3. The polymer composition of claim 1, wherein the hydrazide-containing crosslinking agent comprises adipic acid dihydrazide.

4. The polymer composition of claim 2, wherein the diacetone acrylamide monomer is present in an amount of 2.5 wt% or more based on the total weight of the composition.

5. The polymer composition of claim 3, wherein the adipic acid dihydrazide or polyhydrazide crosslinking agent is present in an amount of 0.8 wt% or greater based on the total weight of the composition.

6. A polymer composition according to any preceding claim, wherein the composition further comprises a monomer selected from the group consisting of methyl (meth)acrylate, 2-ethyl (meth)acrylate, n-butyl (meth)acrylate, tert-butyl (meth)acrylate, isobutyl (meth)acrylate, cyclohexyl (meth)acrylate, 2-ethylhexyl (meth)acrylate, isobornyl (meth)acrylate, 2-octyl (meth)acrylate, styrene, (meth)acrylic acid, itaconic acid, a sulfuric acid monomer, and a phosphorous acid monomer.

7. A polymer composition according to any preceding claim, wherein the weight ratio of first stage polymer to second stage polymer is from 50:50 to 97.5:2.

5.

8. A polymer composition according to any preceding claim, wherein the second stage polymer is present in an amount of 2.5 wt% to 40 wt%, based on the total weight of the composition.

9. The polymer composition according to any preceding claim, wherein the first stage polymer has a theoretical T of -100°C to 50°C. g .

10. A polymer composition according to any preceding claim, wherein the second stage polymer has a theoretical T of -50°C to 250°C. g .

11. A polymer composition according to any preceding claim, wherein the weight % ratio of aldehyde or ketone monomer of the first stage polymer to aldehyde or ketone monomer of the second stage polymer is from 1 :10 to 1 :0.5 based on the total monomer weight of the respective stages.

12. An architectural coating composition comprising a polymer composition according to any one of the preceding claims.

13. The architectural coating composition according to claim 11, further comprising one or more of the following: a pigment, a dispersant, a filler, a coalescing agent, a pH adjuster, a plasticizer, a defoamer, a surfactant, a thickener, a biocide, a co-solvent, and combinations thereof.

14. The architectural coating composition of claim 11 or claim 12, wherein the coating composition exhibits at least one of the following properties: (i) Scratch resistance when scratched with a plastic spoon (ii) Scratch resistance when scratched with a plastic fork (iii) Abrasion resistance when scratched with a rubber sole As measured by visual rating of damage caused to the coating.

15. A method of preparing a multistage polymer emulsion composition according to any preceding claim, the method comprising: (i) Preparation of a first stage polymer from a first pre-emulsion of monomers and initiator (ii) preparing a second stage polymer from the second stage monomer pre-emulsion by feeding the second stage monomer pre-emulsion into the first stage polymer dispersion in the presence of a free radical polymerization initiator.

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