Sealant and caulk polymer compositions

Abstract

A multistage aqueous emulsion polymer is provided that includes a) a first stage polymer having a Tg from -10°C to -50°C and a second stage polymer having a Tg less than the Tg of the first stage polymer, where at least one of the first or second stage polymers includes at least one C1-C20 alkyl (meth)acrylate. When the multistage emulsion polymer is formulated into a caulk composition that has substantially no plasticizers and / or no polyurethane, the caulk composition meets the requirement of a Class 35 caulk according to ASTM C719-22.

Description

[0001] SEALANT AND CAULK POLYMER COMPOSITIONS

[0002] FIELD OF THE INVENTION

[0003] Acrylate polymers suitable for use in caulk and sealant compositions.

[0004] BACKGROUND

[0005] Caulks and sealants may be used to fill in gaps or create a waterproof or water-resistant barrier between two or more different substrates. Acrylic emulsion polymers are commonly used for this purpose due to their good balance of water-resistance (hydrophobicity), flexibility, adhesion, durability (e.g., dirt pick up resistance), and cost.

[0006] Retention of flexibility in challenging environmental conditions, especially wide temperature swings, as may be encountered in outdoor applications, is an important property of caulks and sealants. The state-of-the-art flexibility requirement for acrylic emulsion polymer- based caulks is commonly referred to as Class 35, where Class 35 is defined as a caulk able to extend / compress 35% of its original length under extreme temperature conditions (ranging from - 27°C to 70°C) without breaking or losing adhesion. This property is tested according to ASTM Standard C719-22 and the standard for Class 35 is according to ASTM C920-18. Currently, all acrylic emulsion polymer-based caulks that meet this standard contain plasticizers. Without plasticizers, the acrylic emulsion polymer-based caulks to date have not been able to achieve Class 35 flexibility requirements. However, plasticizers can reduce the toughness and durability of the sealant, hence there has been a push in recent years to move to plasticizer-free formulations of acrylic-based caulks that meet the Class 35 standard. Other downsides to the use of plasticizers include increased mildew and dirt pickup, migration out of the sealant which causes the sealant to lose its flexibility, environmental and / or health concerns, and their cost.

[0007] In some applications, polyurethane dispersions are added to acrylate-based caulks or sealant compositions to provide the needed physical properties but this approach can increase costs significantly since polyurethanes are generally more expensive than acrylates. Thus, it would be desirable to provide an acrylate that enables a caulk or sealant to pass the Class 35 test, without the use of polyurethanes and / or without the use of plasticizers. US 1 1008491 relates to low tack, low temperature flexible aqueous caulk or sealant compositions comprising multistage aqueous emulsion copolymers having a hard stage and a soft stage.

[0008] US 9777166 relates to aqueous caulk or sealant compositions that are substantially free of any plasticizer comprising an aqueous emulsion copolymer having a broad measured glass transition temperature, soft phases and hard phases, and two separate Tan Delta transition temperatures.

[0009] US 8193278 relates to filled aqueous caulk and sealant compositions made from high solids aqueous binders chosen from copolymers having a mixture of backbone acid and hydroxyl groups.

[0010] US 6060532 relates to an elastomeric composition which contains a multi-staged emulsion polymer binder and a photosensitive composition.

[0011] SUMMARY

[0012] In this invention, the problem of meeting the stringent Class 35 test requirements for a caulk or sealant has been solved by providing a multistage polymer that includes first soft stage polymer and a second soft stage polymer which has a Tg even lower than the first stage polymer. The first polymer provides toughness while the second, even softer polymer, provides flexibility. By combining these two types of polymers the inventors were surprisingly able to achieve a flexible polymer that is also tough without including a plasticizer.

[0013] By incorporating a biobased monomer (such as n-butyl acrylate, isobutyl acrylate, 2-octyl acrylate, for example) in at least one of the stages, it was also observed that the flexibility of the caulk was maintained or improved and the caulk or sealant has the additional environmental advantage of including at least some renewable content.

[0014] According to an aspect of the invention, a multistage aqueous emulsion polymer is provided, where the multistage aqueous emulsion polymer comprises, consists of or consists essentially of a) a first stage polymer and b) a second stage polymer.

[0015] The a) first stage polymer has a Tg from -10°C to -50°C, as calculated according to the Fox equation, and comprises, consists of, or consists essentially of, as polymerized monomers: i) one or more ethylenically unsaturated non-ionic monomer: ii) one or more ethylenically unsaturated acid monomer, iii) optionally one or more ethylenically unsaturated crosslinking monomer; and the b) second stage polymer has a Tg, as calculated according to the Fox equation, of less than the Tg of the first stage polymer and the second stage polymer comprises, consists of, or consists essentially of, as polymerized monomers: iv) one or more ethylenically unsaturated non-ionic monomer, which may be the same or different from the monomer i), preferably different from the monomer i) v) one or more ethylenically unsaturated acid monomer, which may be the same or different from the monomer ii) vi) optionally one or more ethylenically unsaturated crosslinking monomer, which may be the same or different, preferably different from the crosslinking monomer iii) in the first stage polymer. According to an embodiment the monomer iii) and the monomer vi) are different.

[0016] In the multistage aqueous emulsion polymer, at least one of the monomers i) or iv) comprises at least one of C1-C20 alkyl (meth)acrylate, preferably at least one Cl -Cl 4 alkyl(meth)acrylate, more preferably at least one Cl -Cl 2 alkyl(meth)acrylate or Cl -CIO alkyl(meth)acrylate, most preferably at least one of lauryl acrylate, lauryl methacrylate, ethyl acrylate, n-butyl acrylate, isobutyl acrylate, 2-methylbutyl acrylate, n-heptyl acrylate, or 2-octyl acrylate; and a weight ratio of the first stage polymer to the second stage polymer is from95:5 to 55:45; preferably from 90:10 to 60:40, preferably from 85: 15 to 65:35, more preferably from 80:20 to 70:30.

[0017] According to another aspect of the invention, a multistage aqueous emulsion polymer is provided, where the multistage aqueous emulsion polymer comprises, consists of, or consists essentially of: a) a first stage polymer having a Tg from -10°C to -50°C, as calculated according to the Fox equation, comprising, as polymerized monomers: i) one or more ethylenically unsaturated non-ionic monomer: ii) 0.25-4wt% of one or more ethylenically unsaturated acid monomer based on a weight of the first stage polymer, iii) 0.01-2wt% of one or more ethylenically unsaturated crosslinking monomer based on a weight of the first stage polymer; and b) a second stage polymer having a Tg from less than -50°C to -70°C, as calculated according to the Fox equation, comprising, as polymerized monomers: iv) one or more ethylenically unsaturated non-ionic monomer which may be the same or different from the monomer i), preferably different from the monomer i), v) 0.25-4wt% of one or more ethylenically unsaturated acid monomer based on a weight of the second stage polymer which may be the same or different from the monomer ii), preferably different from the monomer ii), vi) 0.01-2wt% of at least one ethylenically unsaturated crosslinking monomer based on a weight of the second stage polymer, which may be the same or different, preferably different from the monomcaulk compositions.

[0018] Figure 2 shows the results of Class 35 testing according to ASTM Standard C719-22 of a caulk composition according to an exemplary embodiment of the invention.

[0019] DETAILED DESCRIPTION

[0020] Unless otherwise indicated, all percentages recited herein are weight percentages.

[0021] “Polymer” as used herein, is meant to include organic molecules with a weight average molecular weight higher than 20,000 g / mol, preferably higher than 50,000 g / mol, as measured by gel permeation chromatography. All molecular weights recited herein are weight average molecular weights (Mw) unless otherwise specified. All molecular weights are measured using gel permeation chromatography using polystyrene standards.

[0022] As used herein, a plasticizer is an added component that gives an otherwise rigid polymer flexibility. A plasticizer may reduce the glass transition temperature (Tg) as measured by differential scanning calorimetry, of the polymer to which it is added. The Fox equation provides an estimate for glass transition temperature of a copolymer based on a weighted average of the glass transition temperatures of homopolymers of each monomer in the copolymer. The Fox equation is:

[0023] 1 / Tg(copolymer)=;(fi / Tgi } + {f? / Tg2} + {fs / Tgs} + . . + {fn / Tgn} where: Tg(polymer) is the calculated Tg of the polymer and Tgi, Tgz, Tgj, . .. Tgn are the respective Tg’s of homopolymers of the monomers 1, 2, 3, ...n, each of which’ s weight fraction in the polymer is f , fj, ft, . , .fn. As is known in the art, the Tg calculated by the Fox equation uses known values of homopolymers of the monomers in the polymer. These homopolymer Tgs are those as reported in the Polymer Handbook, 4th Edition; J. Brandrup (Editor), E. H. Immergut (Editor), E. A. Grulke (Editor); ISBN: 978-0-471-47936-9 May 2003..

[0024] As used herein, the terms, “caulk” and “sealant” are interchangeable and refer to hydrophobic and flexible materials / products used to fill in the seams, gaps, holes, joints, spaces, or surfaces of a substrate or between two or more substrates, and to maintain a watertight, airtight, or steamtight adhesion. Sealants (and caulks) are products intended to make airtight, watertight or steamtight seams, fill gaps, holes, joints, or provide a sealed surface between adjoining surfaces or edges of substrates. Desirably, sealants and caulks are water-resistant and flexible over time and do not embrittle upon repeated exposure to water and moist environments that also experience changes in temperature. Therefore, desirable properties are being hydrophobic (low water uptake), having good flexibility at low temperatures, and having good extension recovery. The present sealant composition(s) are unexpectedly water resistant, flexible, and have good adhesion to surfaces such as but not limited to, plastics, glass, wood, stone, ceramic, and / or metal and importantly are able to meet the Class 35 flexibility requirements according to ASTM Standard C719-22 and ASTM C920-18.

[0025] The term “bio-based” as used herein means products or materials that are derived in whole or in part from biomass resources, i.e. biomass-derived. Biomass resources are organic materials that are available on a renewable or recurring basis such as crop residues, wood residues, grasses, and aquatic plants. Products or materials, monomers, polymers, etc. containing any amount of bio-based content are referred to as “bio-based” or “biobased”. Products made entirely from petrochemical resources are referred to as non-bio-based products. Percent bio-based carbon content, also referred to herein as “biocarbon content” (BCC) is a measure of the amount of biomass-derived or bio-based carbon in a product as compared to its total organic carbon content (TOC). Percent bio carbon content is measured according to ASTM D6866-22, Method B. The biocarbon content (BCC) of a product is reported as a fraction of total organic carbon content (TOC) and not on its weight according to ASTM D6866-22 Method B.

[0026] As used herein “substantially free of’ or “comprising substantially no” means including less than 5, 3, 2, 1, 0.5, 0.1, 0.05, or less than 0.01 wt%, or less than 1000 ppm wt, or less than 100 ppm wt, less than 50 ppm wt less than 10 ppm wt or none of the recited component by weight of the composition, or no detectable amount of the recited component. In some embodiments, the recited component was not intentionally added.

[0027] Multistage Aqueous Emulsion Polymer:

[0028] The multistage aqueous emulsion polymer comprises, consists of, or consists essentially of a first stage polymer and a second stage polymer. According to an embodiment, a weight ratio of the first stage polymer to the second stage polymer is from 95:5 to 55:45, preferably from 90: 10 to 60:40, preferably from 85: 15 to 65:35, more preferably from 80:20 to 70:30. According to another embodiment, the multi stage aqueous emulsion polymer is prepared such that the first stage polymer is polymerized first, followed by the polymerization of the second stage polymer. Thus, the multistage polymer may be in the form of a core / shell particle, such that the first stage polymer comprises, consists of, or consists essentially of the interior or core of the particle, and the second stage polymer comprises, consists of, or consists essentially of the exterior or shell of the polymeric particle.

[0029] According to an embodiment, at least one of the first and / or second stage polymers comprises at least one C1-C20 alkyl (meth)acrylate, preferably at least one Cl -Cl 4 alkyl(meth)acrylate, more preferably at least one Cl -Cl 2 alkyl(meth)acrylate or Cl -CIO alkyl(meth)acrylate, preferably at least one of lauryl acrylate, lauryl methacrylate, ethyl acrylate, n-butyl acrylate, isobutyl acrylate, 2-methylbutyl acrylate, n-heptyl acrylate, or 2-octyl acrylate. As detailed below, these monomers may comprise at least a portion of the ethylenically unsaturated non-ionic monomers i) in the first stage polymer and / or at least a portion of the ethylenically unsaturated non-ionic monomers v) in the second stage polymer. According to an embodiment, the monomers lauryl acrylate, lauryl methacrylate, ethyl acrylate, n-butyl acrylate, isobutyl acrylate, 2-methylbutyl acrylate, n-heptyl acrylate, or 2-octyl acrylate may be at least partially biobased. For example, biocarbon content (BCC) of the lauryl acrylate, lauryl methacrylate, ethyl acrylate, n-butyl acrylate, isobutyl acrylate, 2-methylbutyl acrylate, n-heptyl acrylate, or 2-octyl acrylate may be at least 1% as measured according to ASTM 6866-22 Method B. Accordingly, the biocarbon content of the multistage aqueous emulsion polymer may be 1% or more as determined by ASTM 6866-22 Method B. Desirably, the biocarbon content of the multistage aqueous emulsion polymer is higher. According to some embodiments, the bio-carbon content of the multistage aqueous emulsion polymer is at least 5, 10, 15, 20, 25, 30, 35, 40, 45, 50, 55, 60, 65, 70, 75, 80, 85, 90, 95, 99, or is 100% as measured according to ASTM 6866-22 Method B.

[0030] As described below, at least one of the first and second stages is crosslinked or crosslinkable, i.e. includes a latent crosslinking agent or monomer, or includes a crosslinking monomer that forms crosslinks during polymerization, e.g. a free-radical polymerizable monomer having two or more, preferably two free-radical polymerizable carbon-carbon double bonds. According to an embodiment, both stages are crosslinked or crosslinkable. According to an embodiment, the first stage and the second stage each includes a different crosslinking monomer. a) First Stage Polymer

[0031] The first stage polymer has a Tg from -10°C to -50°C, as calculated according to the Fox equation. Importantly, the Tg of the first stage polymer is higher than the Tg of the second stage polymer, as calculated according to the Fox equation. According to some embodiments, the Tg of the first stage polymer may be from -45°C to -15°C, or from -40°C to -20°C, or from -35°C to - 25 °C, as calculated according to the Fox equation. According to some embodiments, the Tg of the first stage polymer may be at least -50, -45, -40, -35, -30, -25, -20, or at least -15°C and the Tg of the first stage polymer may be at most -10, -15, -20, -25, -30, -35, -40, or at most -45°C, as calculated according to the Fox equation.

[0032] The a) first stage polymer comprises, consists of or consists essentially of the following, as polymerized monomers: i) one or more ethylenically unsaturated non-ionic monomers; ii) one or more ethylenically unsaturated acid monomers, and iii) optionally one or more ethylenically unsaturated crosslinking monomers. i) Ethylenically Unsaturated Non-Ionic Monomer

[0033] According to some embodiments, the first stage polymer may comprise at least one of C1-C20 alkyl (meth)acrylates, preferably at least one C1-C14 alkyl(meth)acrylates, more preferably at least one C1-C12 alkyl(meth)acrylates or C1-C10 alkyl(meth)acrylates, most preferably at least one of lauryl acrylate, lauryl methacrylate, ethyl acrylate, n-butyl acrylate, isobutyl acrylate, 2-methylbutyl acrylate, n-heptyl acrylate, or 2-octyl acrylate. Importantly, at least one of the first stage polymer and the second stage polymer may include at least one of these monomers. In other words, at least one of monomer i) in the first stage polymer and monomer iv) in the second stage polymer comprises at least one of C1-C20 alkyl (meth)acrylates, preferably at least one Cl -Cl 4 alkyl(meth)acrylates, more preferably at least one of C1-C12 alkyl(meth)acrylates or C1-C10 alkyl(meth)acrylates, preferably at least one of lauryl acrylate, lauryl methacrylate, ethyl acrylate, n-butyl acrylate, isobutyl acrylate, 2- methylbutyl acrylate, n-heptyl acrylate, or 2-octyl acrylate, more preferably at least one of ethyl acrylate, n-butyl acrylate, isobutyl acrylate, 2-methylbutyl acrylate, n-heptyl acrylate, or 2-octyl acrylate. According to an embodiment, at least one of monomer i) in the first stage polymer and monomer iv) in the second stage polymer comprises at least one of lauryl acrylate, lauryl methacrylate, ethyl acrylate, n-butyl acrylate, isobutyl acrylate, 2-methylbutyl acrylate, n-heptyl acrylate, or 2-octyl acrylate, more preferably at least one of ethyl acrylate, n-butyl acrylate, isobutyl acrylate, 2-methylbutyl acrylate, n-heptyl acrylate, or 2-octyl acrylate. According to an embodiment at least one of the lauryl acrylate, lauryl methacrylate, ethyl acrylate, n-butyl acrylate, isobutyl acrylate, 2-methylbutyl acrylate, n-heptyl acrylate, or 2-octyl acrylate is biobased.

[0034] According to some embodiments, the bio-carbon content of monomer i) is at least 5, 10, 15, 20, 25, 30, 35, 40, 45, 50, 55, 60, 65, 70, 75, 80, 85, 90, 95, 99, or is 100% as measured according to ASTM 6866-22 Method B.

[0035] According to an embodiment, the monomer i) may comprise at least one of C1-C20 alkyl (meth)acrylates, C1-C14 alkyl(meth)acrylates, C1-C12 alkyl(meth)acrylates, C1-C10 alkyl(meth)acrylates, vinyl aromatic monomers, hydrocarbons having at least one free radical polymerizable C=C double bond, vinyl versatate, vinyl acetate, hydroxy (meth)acrylates, preferably Cl -Cl 2 alkyl (meth)acrylates, vinyl aromatic monomers, hydroxy (meth)acrylates, more preferably Cl -Cl 2 alkyl (meth)acrylate, hydroxy (meth)acrylates.

[0036] Non-limiting examples of suitable monomers i) are vinyl- and (meth)acrylic-containing monomers such as the alkyl esters (in particular, the C1-C20 alkyl esters, where the alkyl group is linear or branched) of acrylic and methacrylic acid such as methyl(meth)acrylate, ethyl(meth)acrylate, n-propyl(meth)acrylate, isopropyl(meth)acrylate, n-butyl(meth)acrylate, isobutyl(meth)acrylate, pentyl(meth)acrylate, 2-ethylhexyl(meth)acrylate, n-octyl (meth)acrylate, n-heptyl methacrylate, decyl (meth)acrylate, dodecyl (meth)acrylate, and stearyl (meth)acrylate; halo- and hydroxyl-substituted alkyl esters of (meth)acrylic acid such as a- chloroethyl(meth)acrylate, 2-hydroxyethyl(meth)acrylate, 2- and 3- hydroxypropyl(meth)acrylate, and 4-hydroxybutyl (meth)acrylate; vinyl esters of linear and branched carboxylic acids having 1 to 25 carbon atoms, preferably 2 to 20 carbon atoms, such as vinyl acetate, vinyl propionate, vinyl butyrate, vinyl valerate, vinyl 2-ethylhexylacrylate, vinyl isononanoate, vinyl laurate, vinyl stearate, vinyl versatate; styrene and styrene derivatives, such as alpha-methylstyrene, 2-chlorostyrene, 4-chlorostyrene, 2,5-dichlorostyrene and 4- methoxystyrene; cyclic or non-cyclic C1-C12 (meth)acrylates or mixtures thereof. For example, the monomer i) may be at least one of methyl (meth)acrylate, ethyl (meth)acrylate, n- propyl(meth)acrylate, isopropyl (meth) acrylate, butyl (meth)acrylates such as n-butyl (acrylate), sec-butyl (meth)acrylate, tert-butyl(meth)acrylate, isomers of pentyl(meth)acrylate, 2 octyl(meth)acrylate, 2-ethylhexyl(meth) acrylate, 2-propylheptyl (meth) acrylate, ethylbutyl(meth)acrylate, isomers of heptyl(meth)acrylate such as n-heptyl(meth)acrylate, isomers of hexyl(meth)acrylate, isomers of octyl(meth) acrylate, isomers of nonyl(meth)acylate, isomers of decyl(meth) acrylate, isomers of undecyl (meth)acryl ate, isomers of lauryl(meth)acrylate, or combinations thereof, cycloalkyl (meth)acrylates such as cyclohexyl(meth)acrylate; aryl and alkaryl esters of (meth)acrylic acid such as phenyl (meth)acrylate, vinyl chloride; olefins such as ethylene; dienes such as butadiene, and the like; and combinations thereof.

[0037] Other non-limiting examples of suitable monomers i) include (meth)acrylonitrile; amide group-containing monomers such as (meth)acrylamide, N,N-dimethylacrylamide, 4- acryloylmorpholine, N-butylacrylamide, N-[3-(dimethylamino)propyl]acrylamide, N,N- diethylacrylamide, N-[2-(dimethylamino)ethyl]acrylamide, N-[2- (diethylamino)ethyl]acrylamide, N-(2-hydroxyethyl)acrylamide, N-Isopropylacrylamide, N- propylacrylamide.

[0038] According to an embodiment, the monomer i) may further comprise at least one of vinyl aromatic monomers, hydrocarbons having at least one free radical polymerizable C=C double bond, vinyl acetate, vinyl versatate, hydroxy (meth)acrylates, (meth)acrylonitrile, amide group- containing monomers, or combinations thereof preferably vinyl aromatic monomers, hydroxy (meth)acrylates, or combinations thereof.

[0039] The monomer i) or mixture of monomers i) may be present in the first stage polymer at 5- 99.7 wt.% by weight of the first stage polymer. According to some embodiments, the first stage polymer may include at least 10, 15, 20, 25, 30, 35, 40, 45, 50, 55, 60, 65, 70, 75, 80, 85, 90 or at least 95 wt.% of monomer(s) a) by weight of the first stage polymer. According to some embodiments, the first stage polymer may include at most 95, 90, 85, 80, 75, 70, 65, 60, 55, 50, 45, 40, 35, 30, 25, 20 15, or at most 5 wt.% of monomer(s) i) by weight of the first stage polymer.

[0040] According to some embodiments, these monomers may be derived from bio-based (meth)acrylic acid and / or bio-based alcohols. ii) Ethylenically Unsaturated Acid Monomer

[0041] The first stage polymer may include one or more unsaturated acid monomers ii). As used herein, “unsaturated” means the monomer includes at least one free-radical polymerizable carboncarbon double bond.

[0042] The first stage polymer may include from 0.25-4.0 wt.%, or 0.4 to 3.5 wt%, or 0.5 to 3 wt%, or 0.5 to 2.5 wt% by weight of the first stage polymer of the one or more acid monomers ii). For example, the first stage polymer may include at least 0.25, 0.3, 0.4, 0.5, 0.6, 0.7, 0.8, 0.9, 1, 1.2, 1.4, 1.6, 1.8, 2, 2.2, 2.4, 2.6, 2.8, 3, 3.2, 3.4, 3.6, or at least 3.8wt.% by weight of the first stage polymer of the one or more acid monomers ii). The first stage polymer may include at most 4, 3.8, 3.6, 3.4, 3.2, 3, 2.8, 2.6, 2.4, 2.2, 2, 1.8, 1.5, 1, or at most 0.5 wt.% by weight of first stage polymer of the one or more carboxylic acid monomers ii). According to some embodiments, the first stage polymer may comprise from 0.1-5wt%, O.15-3wt%, 0.2-2 wt%, or from 0.25-1.5 wt% of the one or more ethylenically unsaturated acid monomers, based on a weight of the first stage polymer. Acid-functionalized monomers ii) may include but are not limited to carboxylic acid- functionalized monomers such as (meth)acrylic acid, beta-carboxyethyl acrylate, maleic acid, fumaric acid, itaconic acid, ethacrylic acid, crotonic acid, citraconic acid, cinnamic acid, l,4,5,6,7,7-hexachloro-5-norbornene-2,3-dicarboxylic acid, or combinations thereof. Also suitable as well as polymerizable unsaturated carboxylic acids are acids such as unsaturated C3- C6 monocarboxylic acids, e.g., monoesters of unsaturated C4-C6 dicarboxylic acids such as monomethylmaleate and mono-ethylmaleate.

[0043] Acid-functionalized monomers ii) may be selected from phosphorus-based or sulfur-based acid-functionalized monomers including non-limiting examples such as: such as: phosphoalkyl (meth)acrylates or acrylates, phospho alkyl (meth)acrylamides or acrylamides, phosphoalkyl crotonates, phosphoalkyl maleates, phosphoalkyl fumarates, phosphodialkyl (meth)acrylates, phosphodialkyl crotonates, vinyl phosphates and (meth)allyl phosphate, phosphate esters of polypropylene glycol mono(meth)acrylate or polyethylene glycol mono(meth)acrylate, polyoxyethylene allyl ether phosphate, vinyl phosphonic acid. Sulfate-based monomers include, without limitation, vinyl- and allyl- sulfonic or sulfuric acids, sulfoethyl (meth)acrylate, arylsulfonic or sulfuric acids, (meth)acrylamidoethane- sulfonic or sulfuric acids, methacrylamido-2- methyl propane- sulfonic or sulfuric acids, and the alkali metal salts of sulfonic and sulfuric acids.

[0044] Preferred acid monomers ii) are (meth)acrylic acid, beta-carboxyethyl acrylate, maleic acid, fumaric acid, itaconic acid, ethacrylic acid, crotonic acid, citraconic acid, cinnamic acid, vinyl phosphonic acid, more preferred are acrylic acid and methacrylic acid. iii) Ethylenically Unsaturated Crosslinking Monomer

[0045] According to an embodiment the first stage polymer may comprise iii) at least one ethylenically unsaturated crosslinking monomer. If the monomer iii) is present, it may be the same as or different, preferably different from the at least one ethylenically unsaturated crosslinking monomer vi) in the second stage polymer, if the crosslinking monomer vi) is present in the second stage polymer. According to an embodiment, the crosslinking monomer iii) in the first stage polymer is different from the crosslinking monomer vi) in the second stage polymer. Preferably, the first stage polymer comprises the crosslinking monomer iii). More preferably, the first stage polymer comprises the crosslinking monomer iii) and the second stage polymers comprises the crosslinking monomer vi). Most preferably, the first stage polymer comprises the crosslinking monomer iii) and the second stage polymer comprises the crosslinking monomer vi) and monomer iii) and monomer vi) are different.

[0046] According to an embodiment, the first stage polymer may comprise from 0.01-10wt% of the iii) at least one ethylenically unsaturated crosslinking monomer, based on a weight of the first stage polymer. For example, the first stage polymer may comprise from 0.01-10 wt% of the monomer iii), or from 0.01-5wt% or from 0.02-2 wt%, or from 0.1-1.5wt%, or 0.5 to 1.5wt% of the monomer iii), based on weight of first stage polymer. The first stage polymer may comprise 0.01-5 wt%, or 0.01-4 wt%, or 0.01-3 wt%, or 0.01-2wt%, or 0.01 to 1.5wt% of the at least one ethylenically unsaturated crosslinking monomer iii) in the first stage polymer, based on a weight of the first stage polymer.

[0047] According to an embodiment, the crosslinking monomer iii) may comprise at least one of hydroxyl functional monomers, keto functional monomers, epoxy functional monomers, monomers comprising two or more free radical polymerizable C=C double bonds, or combinations of monomers thereof.

[0048] Nonlimiting examples of such monomers iii) including carbonyl or 1,3 -dicarbonyl groups, or epoxy groups, are acetoacetate moiety containing monomers such as 2-acetoacetoxyethyl (meth)acrylate, 3 -acetoacetoxy propyl (meth)acrylate, 4-acetoacetoxybutyl (meth)acrylate, 2- cyanoacetoxyethyl (meth)acrylate, 3 -cyanoacetoxypropyl (meth)acrylate, 4-cyanoacetoxybutyl (meth)acrylate, N-(2-acetoacetoxy ethyl) (meth)acrylamide, allyl acetoacetate, 2,3- di(acetoacetoxy)propyl (meth)acrylate, vinyl acetoacetate, N-methylol acrylamide, N-isobutoxy acrylamide, diacetone acrylamide, acetoacetoxyethyl methacrylate, glycidyl (meth)acrylate, allyl glycidyl ether, or combinations thereof. These monomers may be self-reacting to form crosslinks. When the first stage first polymer comprises one or more carbonyl-containing monomers (such as a monomer bearing an acetoacetate functionality, or keto functional groups), crosslinking reactions involving these monomers may be achieved by adding carbonyl-reactive crosslinking agents or compounds to the aqueous multistage polymer emulsion. Examples of carbonyl-reactive compounds include polyfunctional amines, hydrazine, alkyl dihydrazines, alkylene dioxime ethers, and dihydrazides of dicarboxylic acids. Crosslinking of the polymers may take place during drying of a composition including the present multistage aqueous emulsion polymer. Non-limiting examples of monomers iii) including at least one hydroxyl group are 2- hydroxy-3 -phen oxypropyl methacrylate, hydroxyalkyl (meth)acrylates or combination thereof; preferably, 4-hydroxy butyl acrylate, 2 -hydroxy ethyl acrylate, 2-hydroxy ethyl methacrylate, 3- hydroxypropyl (meth)acrylate, 2,3-dihydroxypropyl(meth)acrylate, or combinations thereof.

[0049] According to an embodiment, the crosslinking monomer iii) may comprise two or more unsaturations. As is known in the art, unsaturations are carbon-carbon double bonds, capable of being free- radical polymerized. Accordingly, monomer iii), if present, when polymerized, provides crosslinks in the polymer. Nonlimiting examples of monomer iii) are crosslinkers with two or more sites of ethylenic unsaturation, such as vinyl or allyl acrylate or methacrylate, diallyl maleate, multifunctional acrylates and methacrylates, methylene-bis-acrylamide, tripropylene glycol diacrylate, 1,3-butylene glycol di(meth)acrylate, 1,12-dodecanediol di(meth)acrylate, decanediol di(meth)acrylate, neopentyl glycol di(meth)acrylate triethylene glycol di(meth)acrylate, tetraethylene glycol di(meth)acrylate, ethylene glycol di(meth)acrylate, diethylene glycol di(meth)acrylate, trimethylolpropane tri(meth)acrylate, 1,3 -butyleneglycol di(meth)acrylate, 1,4- butyleneglycol di(meth)acrylate, dipentaerythritol pentaacrylate, pentaerythritol tetraacrylate, 1,10-decanediol di(meth)acrylate, ethoxylated (2) bisphenol A di(meth)acrylate, 1,3-propanediol di(meth)acrylate, 1,4-butanediol diacrylate, 1,4-butan ediol dimethacrylate, 1,6-hexanediol diacrylate, 1,6 hexanediol dimethacrylate, dially phthalate, allyl(meth)acrylate, divinylbenzene, or combinations thereof. b) Second Stage Polymer

[0050] The b) second stage polymer comprises, consists of or consists essentially of the following, as polymerized monomers: iv) one or more ethylenically unsaturated non-ionic monomers; v) one or more ethylenically unsaturated acid monomers; and vi) optionally one or more ethylenically unsaturated crosslinking monomers., where the crosslinking monomer vi), if present, may be the same or different from the monomer iii) in the first stage polymer, and preferably is different from the monomer iii).

[0051] The Tg of the second stage polymer is from less than -50°C to -70°C, as calculated according to the Fox equation. Importantly, the Tg of the second stage polymer is lower than the Tg of the first stage polymer. According to some embodiments, the Tg of the second stage polymer may be from -65°C to -55°C, or from -60°C to -55°C, as calculated according to the Fox equation. According to some embodiments, the Tg of the second stage polymer may be at least -70, -65, - 60, or at least -51 °C and the Tg of the second stage polymer may be at most -51, or at most -55°C, as calculated according to the Fox equation. iv) Ethylenically Unsaturated Non-ionic Monomer

[0052] According to some embodiments, the ethylenically unsaturated non-ionic monomer iv) in the second stage polymer may comprise at least one of C1-C20 alkyl (meth)acrylate, preferably at least one Cl -Cl 4 alkyl(meth)acrylates, more preferably at least one Cl -Cl 2 alkyl (meth)acrylates or Cl -CIO alkyl(meth)acrylates, most preferably at least one of lauryl acrylate, lauryl methacrylate, ethyl acrylate, n-butyl acrylate, isobutyl acrylate, 2-methylbutyl acrylate, n-heptyl acrylate, or 2- octyl acrylate. Importantly, at least one of the first stage polymer and the second stage polymer may include at least one of these monomers. In other words, at least one of monomer i) in the first stage polymer and monomer iv) in the second stage polymer comprises at least one of C1-C20 alkyl (meth)acrylates, preferably at least one Cl -Cl 4 alkyl(meth)acrylates, more preferably at least one of Cl -Cl 2 alkyl(meth)acrylates or Cl -CIO alkyl(meth)acrylates, preferably at least one of lauryl acrylate, lauryl methacrylate, ethyl acrylate, n-butyl acrylate, isobutyl acrylate, 2- methylbutyl acrylate, n-heptyl acrylate, or 2-octyl acrylate, more preferably at least one of ethyl acrylate, n-butyl acrylate, isobutyl acrylate, 2-methylbutyl acrylate, n-heptyl acrylate, or 2-octyl acrylate. According to an embodiment, at least one of monomer i) in the first stage polymer and monomer iv) in the second stage polymer comprises at least one of lauryl acrylate, lauryl methacrylate, ethyl acrylate, n-butyl acrylate, isobutyl acrylate, 2-methylbutyl acrylate, n-heptyl acrylate, or 2-octyl acrylate, more preferably at least one of ethyl acrylate, n-butyl acrylate, isobutyl acrylate, 2-methylbutyl acrylate, n-heptyl acrylate, or 2-octyl acrylate. According to an embodiment at least one of the lauryl acrylate, lauryl methacrylate, ethyl acrylate, n-butyl acrylate, isobutyl acrylate, 2-methylbutyl acrylate, n-heptyl acrylate, or 2-octyl acrylate is biobased. The ethylenically unsaturated non-ionic monomer iv) may be the same or different from the ethylenically unsaturated non-ionic monomer i).

[0053] According to some embodiments, the bio-carbon content of monomer iv) is at least 5, 10, 15, 20, 25, 30, 35, 40, 45, 50, 55, 60, 65, 70, 75, 80, 85, 90, 95, 99, or 100% as measured according to ASTM 6866-22 Method B. According to an embodiment, the monomer iv) may comprise at least one of C1-C20 alkyl (meth)acrylates, C1-C14 alkyl(meth)acrylates, C1-C12 alkyl(meth)acrylates, C1-C10 alkyl(meth)acrylates, vinyl aromatic monomers, hydrocarbons having at least one free radical polymerizable C=C double bond, , vinyl versatate, vinyl acetate, hydroxy (meth)acrylates, , preferably Cl -Cl 2 alkyl (meth)acrylates, vinyl aromatic monomers, hydroxy (meth)acrylates, more preferably Cl -Cl 2 alkyl (meth)acrylates, hydroxy (meth)acrylates.

[0054] Non-limiting examples of suitable monomers iv) are vinyl- and (meth)acrylic-containing monomers such as the alkyl esters (in particular, the Cl -Cl 8 alkyl esters, where the alkyl group is linear or branched) of acrylic and methacrylic acid such as methyl(meth)acrylate, ethyl(meth)acrylate, n-propyl(meth)acrylate, isopropyl(meth)acrylate, n-butyl(meth)acrylate, isobutyl(meth)acrylate, pentyl(meth)acrylate, 2-ethylhexyl(meth)acrylate, n-octyl (meth)acrylates, n-heptyl methacrylate, decyl (meth)acrylate, dodecyl (meth)acrylate, and stearyl (meth)acrylate; halo- and hydroxyl-substituted alkyl esters of (meth)acrylic acid such as a- chloroethyl(meth)acrylate, 2-hydroxyethyl(meth)acrylate, 2- and 3- hydroxypropyl(meth)acrylate, and 4-hydroxybutyl (meth)acrylate; vinyl esters of linear and branched carboxylic acids having 1 to 25 carbon atoms, preferably 2 to 20 carbon atoms, such as vinyl acetate, vinyl propionate, vinyl butyrate, vinyl valerate, vinyl 2-ethylhexylacrylate, vinyl isononanoate, vinyl laurate, vinyl stearate, vinyl versatate; styrene and styrene derivatives, such as alpha-methylstyrene, 2-chlorostyrene, 4-chlorostyrene, 2, 5 -dichlorostyrene and 4- methoxystyrene; cyclic or non-cyclic Cl -Cl 2 (meth)acrylates or mixtures thereof. For example, the monomer iv) may be at least one of methyl (meth)acrylate, ethyl (meth)acrylate, n- propyl(meth)acrylate, isopropyl (meth) acrylate, butyl (meth)acrylates such as n-butyl(acrylate), sec-butyl (meth)acrylate, tert-butyl (meth)acrylate, isomers of pentyl (meth)acry late, 2 octyl(meth)acrylate, 2-ethylhexyl(meth) acrylate, 2-propylheptyl (meth) acrylate, ethylbutyl(meth)acrylate, isomers of heptyl(meth)acrylate such as n-heptyl(meth)acrylate, isomers of hexyl (meth)acrylate, isomers of octyl(meth) acrylate, isomers of nonyl(meth)acylate, isomers of decyl(meth) acrylate, isomers of undecyl(meth)acrylate, isomers of lauryl(meth)acrylate, or combinations thereof, cycloalkyl (meth)acrylates such as cyclohexyl(meth)acrylate; aryl and alkaryl esters of (meth)acrylic acid such as phenyl (meth)acrylate, vinyl chloride; olefins such as ethylene; dienes such as butadiene, and the like; and combinations thereof. Other non-limiting examples of suitable monomers iv) include (meth)acrylonitrile; amide group-containing monomers such as (meth)acrylamide, N,N-dimethylacrylamide, 4- acryloylmorpholine, N-butylacrylamide, N-[3-(dimethylamino)propyl]acrylamide, N,N- diethylacrylamide, N-[2-(dimethylamino)ethyl]acrylamide, N-[2- (diethylamino)ethyl]acrylamide, N-(2-hydroxyethyl)acrylamide, N-Isopropylacrylamide, N- propylacrylamide. .

[0055] According to an embodiment, the monomer iv) further comprises at least one of hydrocarbons having at least one free radical polymerizable C=C double bond, vinyl aromatic monomers, vinyl versatate, vinyl acetate, hydroxy(meth)acrylates, (meth)acrylonitrile, amide group-containing monomers, or combinations thereof, preferably vinyl aromatic monomers, hydroxy (meth)acrylates, or combinations thereof.

[0056] The monomer iv) or mixture of monomers iv) may be present in the second stage polymer at 5-99.7 wt.% by weight of the second stage polymer. According to some embodiments, the second stage polymer may include at least 10, 15, 20, 25, 30, 35, 40, 45, 50, 55, 60, 65, 70, 75, 80, 85, 90 or at least 95 wt.% of monomer(s) a) by weight of the second stage polymer. According to some embodiments, the second stage polymer may include at most 95, 90, 85, 80, 75, 70, 65, 60, 55, 50, 45, 40, 35, 30, 25, 20 15, or at most 5 wt.% of monomer(s) iv) by weight of the second stage polymer.

[0057] According to some embodiments, these monomers may be derived from bio-based (meth)acrylic acid and / or bio-based alcohols. v) Ethylenically Unsaturated Acid Monomer

[0058] The second stage polymer may include one or more unsaturated acid monomer v). As used herein, “unsaturated” means the monomer includes at least one free-radical polymerizable carboncarbon double bond.

[0059] The unsaturated acid monomer v) may be the same or different from the unsaturated acid monomer ii) in the first stage polymer.

[0060] The second stage polymer may include from 0.25-4 wt.%, or 0.4 to 3.5 wt%, or 0.5 to 3 wt%, or 0.5 to 2.5 wt% by weight of the second stage polymer of the one or more acid monomers v). For example, the second stage polymer may include at least 0.25, 0.3, 0.4, 0.5, 0.6, 0.7, 0.8, 0.9, 1, 1.2, 1.4, 1.6, 1.8, 2, 2.2, 2.4, 2.6, 2.8, 3, 3.2, 3.4, 3.6, or at least 3.8wt.% by weight of the second stage polymer of the one or more acid monomers v). The second stage polymer may include at most 4, 3.8, 3.6, 3.4, 3.2, 3, 2.8, 2.6, 2.4, 2.2, 2, 1.8 1.5, 1, or at most 0.5 wt.% by weight of second stage polymer of the one or more carboxylic acid monomers v). According to some embodiments, the second stage polymer may comprise from 0.1-5wt%, O.15-3wt%, 0.2-2 wt%, or from 0.25-1.5 wt% of the one or more ethylenically unsaturated acid monomers, based on a weight of the second stage polymer.

[0061] Acid-functionalized monomers v) may include but are not limited to carboxylic acid- functionalized monomers such as (meth)acrylic acid, beta-carboxyethyl acrylate, maleic acid, fumaric acid, itaconic acid, ethacrylic acid, crotonic acid, citraconic acid, cinnamic acid, 1,4, 5, 6, 7, 7-hexachloro-5-norbornene-2,3-di carboxylic acid, or combinations thereof. Also suitable as well as polymerizable unsaturated carboxylic acids are acids such as unsaturated C3- C6 monocarboxylic acids, e.g., monoesters of unsaturated C4-C6 dicarboxylic acids such as monomethylmaleate and mono-ethylmaleate.

[0062] Acid functionalized monomers v) may be selected from phosphorus-based or sulfur-based acid-functionalized monomers may be used, including non-limiting examples such as: phosphoalkyl (meth)acrylates or acrylates, phospho alkyl (meth)acrylamides or acrylamides, phosphoalkyl crotonates, phosphoalkyl maleates, phosphoalkyl fumarates, phosphodialkyl (meth)acrylates, phosphodialkyl crotonates, vinyl phosphates and (meth)allyl phosphate, phosphate esters of polypropylene glycol mono(meth)acrylate or polyethylene glycol mono(meth)acrylate, polyoxyethylene allyl ether phosphate, vinyl phosphonic acid, Sulfate-based monomers include, without limitation, vinyl- and allyl- sulfonic or sulfuric acids, sulfoethyl (meth)acrylate, aryl- sulfonic or sulfuric acids, (meth)acrylamidoethane- sulfonic or sulfuric acids, methacrylamido-2-methyl propane- sulfonic or sulfuric acids, and the alkali metal salts of sulfonic and sulfuric acids.

[0063] Preferred acid monomers v) are (meth)acrylic acid, beta-carboxyethyl acrylate, maleic acid, fumaric acid, itaconic acid, ethacrylic acid, crotonic acid, citraconic acid, cinnamic acid, vinyl phosphonic acid, more preferred are acrylic acid and methacrylic acid. vi) Ethylenically Unsaturated Crosslinking Monomer According to an embodiment the second stage polymer may comprise vi) at least one ethylenically unsaturated crosslinking monomer. If the monomer vi) is present, it may be the same or different, preferably different from the at least one ethylenically unsaturated crosslinking monomer iii) in the first stage polymer, if the crosslinking monomer vi) is present in the second stage polymer. According to an embodiment, the crosslinking monomer vi) in the second stage polymer is different from the crosslinking monomer iii) in the first stage polymer. Preferably, the second stage polymer comprises the crosslinking monomer vi). More preferably, the first stage polymer comprises the crosslinking monomer iii) and the second stage polymers comprises the crosslinking monomer vi). Most preferably, the first stage polymer comprises the crosslinking monomer iii) and the second stage polymer comprises the crosslinking monomer vi), and monomer iii) and monomer vi) are different.

[0064] According to an embodiment, the second stage polymer may comprise from 0.01-10wt% of the vi) at least one ethylenically unsaturated crosslinking monomer, based on a weight of the second stage polymer. For example, the second stage polymer may comprise from 0.01-10 wt% of the monomer vi), or from 0.01-5 wt% or from 0.02-2 wt%, or from 0.1 -1.5 wt%, or 0.5 to 1.5wt% of the monomer iii), based on weight of second stage polymer. The second stage polymer may comprise 0.01-5 wt%, or 0.01-4 wt%, or 0.01-3 wt%, or 0.01-2wt%, or 0.01 to 1.5wt% of the at least one ethylenically unsaturated crosslinking monomer vi) in the second stage polymer, based on a weight of the second stage polymer.

[0065] According to an embodiment, the crosslinking monomer vi) may comprise at least one of hydroxyl functional monomers, keto functional monomers, epoxy functional monomers, monomers comprising two or more free radical polymerizable C=C double bonds, or combinations of monomers thereof.

[0066] Nonlimiting examples of such monomers vi) including carbonyl or 1,3-dicarbonyl groups, or epoxy groups, are acetoacetate moiety containing monomers such as 2-acetoacetoxyethyl (meth)acrylate, 3-acetoacetoxypropyl (meth)acrylate, 4-acetoacetoxybutyl (meth)acrylate, 2- cyanoacetoxyethyl (meth)acrylate, 3 -cyanoacetoxypropyl (meth)acrylate, 4-cyanoacetoxybutyl (meth)acrylate, N-(2-acetoacetoxy ethyl) (meth)acrylamide, allyl acetoacetate, 2,3- di (acetoacetoxy )propyl (meth)acrylate, vinyl acetoacetate, N-methylol acrylamide, N-isobutoxy acrylamide, diacetone acrylamide, acetoacetoxyethyl methacrylate, glycidyl (meth)acrylate, allyl glycidyl ether, or combinations thereof. These monomers may be self-reacting to form crosslinks. When the second stage polymer comprises one or more carbonyl-containing monomers (such as a monomer bearing an acetoacetate functionality, or keto functional groups), crosslinking reactions involving these monomers may be achieved by adding carbonyl -reactive crosslinking agents or compounds to the aqueous multistage polymer emulsion. Examples of carbonyl-reactive compounds include polyfunctional amines, hydrazine, alkyl dihydrazines, alkylene dioxime ethers, and dihydrazides of dicarboxylic acids. Crosslinking of the polymers may take place during drying of a composition including the present multistage aqueous emulsion polymer.

[0067] Non-limiting examples of monomers vi) including at least one hydroxyl group are 2- hydroxy-3 -phen oxypropyl methacrylate, hydroxyalkyl (meth)acrylates or combination thereof; preferably, 4-hydroxy butyl acrylate, 2 -hydroxy ethyl acrylate, 2-hydroxy ethyl methacrylate, 3- hydroxypropyl (meth)acrylate, 2,3-dihydroxypropyl(meth)acrylate, or combinations thereof.

[0068] According to an embodiment, the crosslinking monomer vi) may comprise two or more unsaturations. As is known in the art, unsaturations are carbon-carbon double bonds, capable of being free- radical polymerized. Accordingly, monomer vi), if present, when polymerized, provides crosslinks in the polymer. Nonlimiting examples of monomer vi) are crosslinkers with two or more sites of ethylenic unsaturation, such as vinyl or allyl acrylate or methacrylate, diallyl maleate, multifunctional acrylates and methacrylates, methylene-bis-acrylamide, tripropylene glycol diacrylate, 1,3-butylene glycol di(meth)acrylate, 1,12-dodecanediol di(meth)acrylate, decanediol di(meth)acrylate, neopentyl glycol di(meth)acrylate triethylene glycol di(meth)acrylate, tetraethylene glycol di(meth)acrylate, ethylene glycol di(meth)acrylate, diethylene glycol di(meth)acrylate, trimethylolpropane tri(meth)acrylate, 1,3 -butyleneglycol di(meth)acrylate, 1,4- butyleneglycol di(meth)acrylate, dipentaerythritol pentaacrylate, pentaerythritol tetraacrylate, 1,10-decanediol diacrylate, ethoxylated (2) bisphenol A diacrylate, 1,3 -propanediol di(meth)acrylate, 1,4-butanediol diacrylate, 1,4-butan ediol dimethacrylate, 1,6-hexanediol diacrylate, 1 ,6 hexanediol dimethacrylate, diallyl phthalate, allyl (meth)acrylate, divinylbenzene, or combinations thereof.

[0069] Methods:

[0070] According to an embodiment, the multi stage aqueous emulsion polymer is prepared such that the first stage polymer is polymerized first, followed by the polymerization of the second stage polymer. Thus, the multistage polymer may be in the form of a core / shell particle, such that the first stage polymer comprises, consists of, or consists essentially of the interior or core of the particle, and the second stage polymer comprises, consists of, or consists essentially of the exterior or shell of the polymeric particle.

[0071] Emulsion polymers and monomers useful to prepare polymeric emulsions or dispersions are known in the art (as described in texts on the subject such as “Emulsion Polymerization: Theory and Practice” by D. C. Blackley published by Wiley in 1975, “Emulsion Polymerization” by F. A. Bovey et al. published by Interscience Publishers in 1965, and “Emulsion Polymerization and Emulsion Polymers” by P.A. Lovell et al. published by Wiley Science in 1997).

[0072] The multi stage aqueous emulsion polymer of the present invention comprises one or more multi stage aqueous emulsion polymers prepared by emulsion polymerization as is well known in the art. The multi stage aqueous emulsion polymer is prepared in two stages. First, the monomers i), ii), iii) are polymerized in a first stage and then monomers iv), v) and vi) are polymerized in a second stage. The polymerization of each stage may proceed as follows.

[0073] Thus, the aqueous acrylic emulsion polymer may be prepared by a multistage emulsion polymerization process, in which at least two stages differing in composition are polymerized in sequential fashion. The emulsion polymer may be prepared by emulsion polymerization of a first mixture of monomers comprising the monomers i), ii), and iii) followed by emulsion polymerization of a mixture of monomers comprising the monomers iv), v) and vi). Each of the mixture of monomers may be added neat or as an emulsion in water; or added in one or more additions or continuously, linearly or nonlinearly, over the reaction period of preparing the multistage emulsion polymer. A monomer emulsion containing all or some portion of each of the monomer mixtures to be polymerized may be prepared using the monomers, water and surfactants.

[0074] One or more surfactants may be added prior to, during, or after the polymerization of each of the monomer mixtures. These surfactants may include anionic and / or nonionic emulsifiers. Examples of suitable nonionic emulsifiers include acyl, alkyl, oleyl, alkylaryl ethoxylates, and copolymers of ethylene oxide and propylene oxide. These products are commercially available, for example, under the name Genapol®, Lutensol® or Emulari®, Rhodasurf®, Tergitol™, and Pluronic™. They include, for example, C4 to C12 mono-, di-, and tri-alkylphenols ethopxylates (EO range 3 to 70), C8 to C18 fatty alcohol ethoxylates, Cl 1-C15 oxo-process alcohol ethoxylates, C16 to C18 fatty alcohol ethoxylates, Cl l oxo-process alcohol ethylates, C13 Oxo-process alcohol ethoxylates, Some of commercially available anionic surfactants include sodium, potassium, and ammonium salts of linear and branched alcohol sulfates (e.g., Polystep® B-5, B-7 available from Stepan), alcohol ether sulfates (e.g., Disponil® FES 32, FES77 and FES993 available from BASF and Polystep® B-l 1, B-12, B-19, B-20, B-22, B-23, B-40, B-41, etc. available from Stepan), linear and branched alkylbenzene sulfonates (e.g., Polystep® A-15 and A-16 available from Stepan), alpha olefin sulfonates (e.g., Polystep® A-18 from Stepan and Rhodacal® DS-4 from Solvay), linear and branched alkyldiphenyloxide disulfonates (e.g., Dowfax™ 2A-1 available from The Dow Chemical Company and Calfax® DB-45 and Calfax® 16L-35 from Pilot Chemical); sulfosuccinates (e.g., Aerosol® A-102, OTPG- 75, MA-80I, etc. available from Solvay), alcohol phosphate esters (e.g., Rhodafac® RS-610 from Solvay and Poly step® P-11, P-12, P-13 from Stepan), di- and tri-styrylphenol sulfates and phosphates (e.g., Polystep® TSP-16S and TSP-16S from Stepan). The amount of surfactants used can typically range from 0 to about 5%, from 0.1% to 3%, from 0.5 to 2%, by weight based on the total weight of monomer quantity.

[0075] Also suitable as stabilizers for the present dispersions are copolymerizable nonionic and anionic surfactants such as those disclosed in US2014 / 0243552. Other suitable polymerizable surfactants are sold under the trade names Hitenol ® BC, Hitenol® KH, Hitenol® AR, Adeka Reasoap SR and Adeka Reasoap ER, Oximulsion® React.

[0076] The polymerization process may be thermally initiated or redox initiated emulsion polymerization. Examples of suitable free radical initiators include hydrogen peroxide, t-butyl hydroperoxide, cumene hydroperoxide, ammonium and / or alkali metal persulfates, sodium perborate, perphosphoric acid, and salts thereof; potassium permanganate, and ammonium or alkali metal salts of peroxydisulfuric acid. The free radical initiators may be used typically at a level of 0.01 % to 3.0 % by weight, based on the total weight of monomers. Redox systems comprising the above described initiators coupled with a suitable reductant may be used in the polymerization process. Examples of suitable reductants include sodium sulfoxylate formaldehyde, ascorbic acid, isoascorbic acid, alkali metal and ammonium salts of sulfur containing acids, such as sodium sulfite, bisulfite, thiosulfate, hydrosulfite, sulfide, hydrosulfide or dithionite, formadinesulfinic acid, acetone bisulfite, glycolic acid, hydroxymethanesulfonic acid, glyoxylic acid hydrate, lactic acid, glyceric acid, malic acid, tartaric acid and salts of the proceeding acids. Metal salts of iron, copper, manganese, silver, platinum, vanadium, nickel, chromium, palladium, or cobalt may be used to catalyze the redox reaction. Chelating agents for the metals may optionally be used.

[0077] Chain transfer agents such as mercaptans, polymercaptan, polyhalogeno, and allyl compounds in the polymerization mixture may be used to regulate the molecular weight of each or either of the first and second stage polymers. Examples of suitable chain transfer agents include 3-mercaptopropionic acid, n-dodecyl mercaptan, t-dodecyl mercaptan, methyl 3- mercaptopropionate, butyl 3 -mercaptopropionate, isooctyl 3 -mercaptopropionate, benzenethiol, azelaic alkylmercaptan, or mixtures thereof. The chain transfer agent may be used in an effective amount to control the molecular weight of each stage of the multistage emulsion polymer, for example, from zero to 1%, from 0.1% to 0.5 %, or from 0.15% to 0.4%, by weight based on the total weight of monomers used for preparing each stage of the multistage emulsion polymer.

[0078] The temperature suitable for polymerization process may be lower than 100°C, in the range of from 30°C to 95°C, or in the range of from 50°C to 90°C. Emulsion polymerization may be seeded or unseeded.

[0079] Applications:

[0080] A caulk composition comprising the multistage aqueous emulsion polymer of the present disclosure is provided. According to an embodiment, the caulk composition comprising the multistage aqueous emulsion polymer of the present disclosure is capable of satisfying ASTM Cl 19-22 Class 35 test according to ASTM C920-18.

[0081] According to an embodiment, the caulk composition comprising the multistage aqueous emulsion polymer the present disclosure is capable of satisfying ASTM C719-22 Class 35 test; wherein the caulk composition comprises substantially no plasticizer and substantially no polyurethane .

[0082] According to an embodiment, a caulk composition comprising the multistage aqueous emulsion polymer the present disclosure is capable of satisfying ASTM C719-22 Class 35 test; wherein the caulk composition comprises substantially no plasticizer or comprises no detectable amount of plasticizer. Non-limiting examples of plasticizers that are not included may comprise at least one of phthalates, benzoates, or combinations therefore. Plasticizers are defined herein as a separate component or mixture of components, that, when added to the multistage emulsion polymer disclosed herein has the effect of depressing its glass transition temperature (Tg), as measured using differential scanning calorimetry, compared to the Tg of the multistage emulsion polymer as measured using differential scanning calorimetry without the plasticizer.

[0083] According to an embodiment, a caulk composition comprising the multistage aqueous emulsion polymer of the present disclosure is capable of satisfying ASTM C719-22 Class 35 test according to ASTM C920-18; wherein the caulk composition comprises substantially no polyurethane. Non-limiting examples of polyurethanes may include those in the form of a dispersion. Such polyurethanes may encompass polymers including, in addition to the urethane bonds, aliphatic polyester, aliphatic polyether, and / or aromatic polyether bonds.

[0084] According to an embodiment, the caulk composition comprising the multistage aqueous emulsion polymer comprises substantially no to zero plasticizer and / or substantially no to zero polyurethane and the caulk satisfies the ASTM C719-22 Class 35 test according to ASTM C920- 18.

[0085] According to an embodiment, the caulk composition comprising the multistage aqueous emulsion polymer comprises no intentionally added plasticizer and / or no intentionally added polyurethane and the caulk satisfies the ASTM C719-22 Class 35 test according to ASTM C920- 18.

[0086] The presence of the plasticizer may be determined by HPLC (high performance liquid chromatography) and / or Infrared spectroscopy (IR) and comparison to known standards. Presence of polyurethane can be determined by IR and comparison to known infrared spectroscopy data for the urethane bond.

[0087] Additives:

[0088] According to an embodiment, the caulk composition further comprises at least one additive comprising at least one of at least one surfactant, at least one rheology modifier, at least one freeze-thaw stabilizer, at least one adhesion promotor, or combinations thereof. According to an embodiment, the caulk composition may further comprise 0 to 95 wt.% of a fdler, wherein a weight ratio of a total amount of the fdler to the multistage aqueous emulsion polymer is from 0 to 1 : 1.5.

[0089] Surfactant

[0090] The caulk composition may include at least one surfactant or dispersant. Non- limiting examples include any known surfactants, such as ammonium, alkali metal, alkaline earth metal, and lower alkyl quaternary ammonium salts of sulfosuccinates, salts of fatty rosin and naphthenic acids, condensation products of sulfonic acid and formaldehyde, carboxylic polymers, higher fatty alcohol sulfates, aryl sulfonates, alkyl sulfonates, alkylaryl sulfonates, alkylphenoxy polyethoxy ethanols or ethylene oxide derivatives of long chain carboxylic acids, as well as polyacid dispersants, such as polyacrylic acid or polymethylacrylic acid or salts thereof, and hydrophobic co-polymeric dispersants, such as co-polymers of acrylic acid, methacrylic acid, or maleic acid with hydrophobic monomers. Other surfactants may be sodium sulfonate, sodium lauryl sulfate, sodium dodecylbenzenesulfonate, potassium stearate, sodium dioctyl sulfosuccinate, sodium dodecyldiphenyloxide disulfonate, onylphenoxyethylpolyethoxyethyl sulfate ammonium salt, sodium styrene sulfonate, sodium dodecyl allyl sulfosuccinate, sodium or ammonium salts of phosphate esters of ethoxylated nonylphenol, sodium octoxynol-3-sulfonate, sodium cocoyl sarcocinate, sodium 1 -alkoxy -2 -hydroxypropyl sulfonate, sodium a-olefin (Cl 4- C16)sulfonate, sulfates of hydroxyalkanols, tetrasodium N-(l,2-dicarboxy ethyl)-N- octadecylsulfosuccinamate, disodium N-octadecylsulfosuccinamate, disodium alkylamido poly ethoxy sulfosuccinate, di sodium ethoxylated nonylphenol half ester of sulfosuccinic acid and the sodium salt of tert-octylphenoxyethoxypolyethoxy ethyl sulfate and combinations thereof. Also suitable are acyl, alkyl, oleyl, and alkylaryl ethoxylates. These products are commercially available, for example, under the tradename Genapol™, Lutensol™ or Emulan™. They include, for example, ethoxylated mono-, di-, and tri-alkylphenols (EO degree: 3 to 80, alkyl substituent radical: C4 to C12) and also ethoxylated fatty alcohols (EO degree: 3 to 80; alkyl radical: C8 to C36), especially C10-C14 fatty alcohol (EO 3-80) ethoxylates, C11-C15 oxo-process alcohol (EO 3-80) ethoxylates, C16-C18 fatty alcohol (EO 3-80) ethoxylates, Cl l oxo-process alcohol (EO 3-80) ethoxylates, C13 oxo-process alcohol (EO 3-80) ethoxylates, polyoxyethylenesorbitan monooleate with 20 ethylene oxide groups, copolymers of ethylene oxide and propylene oxide having a minimum ethylene oxide content of 10% by weight, the polyethylene oxide (EO 3-80) ethers of oleyl alcohol, and the polyethene oxide (EO 3-80) ethers of nonylphenol. Particularly suitable are the polyethylene oxide (EO 3-80) ethers of fatty alcohols, more particularly of oleyl alcohol, stearyl alcohol or Cl 1 alkyl alcohols. Preferred surfactants are salts of sulfosuccinates, alkylaryl sulfonates, and alkyl alcohol ethoxylates (EO 5-40). More preferred surfactants are dihexyl sulfosuccinate, dioctyl sulfosuccinate, dodecylbenzene sulfonate, tridecyl alcohol ethoxylates (EO 10-40).

[0091] Rheology modifier

[0092] The caulk composition may optionally include at least one rheology modifier. The rheology modifier is intended to raise the viscosity of the caulk. Although pigments or particulate additives can also increase the viscosity of the caulk, these rheology modifiers are understood not to include pigments, particulates, or fibers.

[0093] The amount of the rheology modifier, if present, is effective, either alone, or in combination with a filler, to raise the viscosity of the caulk composition to at least about 350,000 cps, preferably about 400,000 cps, more preferably about 450,000 cps, most preferably about 500,000 cps, as measured by a Helipath viscometer using T-E-bar spindle. According to some embodiments, the caulk composition may include from 0.1 to 2 wt. %, preferably from 0.0 to 1.5 wt.%, more preferably from 0.0 to 0.5 wt .%. of rheology modifier based on a total weight of the caulk composition.

[0094] Several illustrative examples of the rheology modifier may include, without limitation, celluloses, gums, associative and non- associative polymers, polyamides, calcium sulfonate derivatives, modified polyureas, castor oil derivatives, hydroxyethylcellulose, carboxymethylcellulose, hydrophobically-modified ethylene oxide urethane (HEUR) polymers, hydrophobically-modified alkali soluble or swellable emulsion (HASE) polymers, hydrophobically-modified hydroxyethyl celluloses (HMHECs), hydrophobically-modified polyacrylamide, alkali soluble emulsions (ASE), and combinations thereof.

[0095] Filler

[0096] The caulk composition may optionally include at least one filler in an amount, either alone or together with the rheology modifier (if present), sufficient to raise the viscosity of the caulk to at least about 350,000 cps, preferably to about 400,000 cps, more preferably to about 450,000 cps, most preferably to about 500,000 cps, as measured by a Helipath viscometer using T-E-bar spindle.

[0097] If present, the caulk composition includes 0-95 wt.% of fdlers and / or pigments by weight of the caulk composition. According to some embodiments, the caulk composition includes at least 5, 10, 15, 20, 25, 30, 35, 40, 45, 50, 55, 60, 65, 70, 75, 80 or at least 90 wt.% of fillers and / or pigments by weight of the sealant composition. According to some embodiments the sealant composition includes at most 95, 90, 85, 80, 75, 70, 65, 60, 55, 50, 45, 40, 35, 30, 25, 20 15, or at most 5 wt.% of fillers and / or pigments by weight of the caulk composition.

[0098] Non-limiting examples of fillers include fibers, such as glass, aramid or polyester fibers; carbon black; colored organic pigments; metal oxides, such as titanium dioxide, zinc oxide, or iron oxide; as well as organic dyes; or combinations thereof. Examples of fillers may include, but not be limited to, zinc oxide, zinc hydroxide, magnesium silicate, calcium silicate, fumed silica, amorphous silica, vapor phase silica, colloidal silica, alumina, aluminum hydroxide, zirconium oxide, cerium oxide, calcium sulfate, barium sulfate, zinc carbonate, calcium carbonate, nepheline syenite, feldspar, diatomaceous earth, talc, aluminosilicates, silica, alumina, clay, kaolin, mica, pyrophyllite, perlite, baryte, Wollastonite, triphenyl phosphate, and combinations thereof. The terms “filler” and “pigment” are used interchangeably herein.

[0099] Freeze-thaw stabilizer

[0100] The caulk composition may optionally include at least one freeze-thaw stabilizer. A freeze-thaw stabilizer is an additive intended to depress the freezing point of the components in the sealant composition and therefore increase the sealant’s resistance to freezing. It also allows the sealant to remain fluid upon thawing. Non-limiting examples are polyols, diols, triols, ethylene glycol, propylene glycol, octylphenol ethoxylate, nonylphenol ethoxylate, or combinations thereof.

[0101] According to some embodiments, if present, the caulk composition includes from 0.0 to 5 wt.%, or from 0.01 to 5 wt% preferably from 0.1 to 3 wt.%, more preferably from 0.01 to 1 wt.% of a freeze-thaw stabilizer, based on a total weight of the composition.

[0102] Adhesion promotor The caulk composition may include at least one adhesion promotor; such as functionalized silanes, alkoxysilanes, epoxysilanes, trialkoxysilanes, aminoalkylsilanes, aminoalkoxysilanes, organotitanates; or combinations thereof.

[0103] According to an embodiment, the caulk composition further comprises at least one adhesion promotor.

[0104] As used herein, an adhesion promotor is an additive that is used to enhance the bonding between a substrate and the caulk. These are also referred to as coupling agents. Such additives work by providing a reactive surface for an adhesive material, i.e., the caulk composition, to attach to, thereby increasing the strength and durability of the bond between the caulk composition and a substrate. Non-limiting examples of suitable adhesion promotors are hydrolysable silanes, epoxy silanes, functional silanes bearing aminoalkyl, mercaptoalkyl, epoxyalkyl, ureido (meth)acrylate and isocyanurate groups. Within these classes, the preferred adhesion promoters are glycidal epoxy functional silanes, and amino alkoxysilanes, such as but not limited to aminopropyltriethoxysilane, aminoethylaminopropyltrimethoxysilane, glycidoxypropyltrimethoxysilane, or combinations thereof.

[0105] According to some embodiments, the caulk composition includes from 0.01 to 1 wt.%, preferably from 0.1 to 0.5 wt.%, more preferably from 0.01 to 0.1 wt.% of an adhesion promotor, based on a total weight of the composition.

[0106] Non-limiting Aspects of the invention are summarized as follows.

[0107] Aspect 1. A multistage aqueous emulsion polymer comprising: a) a first stage polymer having a Tg from -10°C to -50°C, as calculated according to the Fox equation, comprising, as polymerized monomers: i) one or more ethylenically unsaturated non-ionic monomer; ii) one or more ethylenically unsaturated acid monomer; iii) optionally one or more ethylenically unsaturated crosslinking monomer; and b) a second stage polymer having a Tg of less than the Tg of the first stage polymer, as calculated according to the Fox equation, comprising, as polymerized monomers: iv) one or more ethylenically unsaturated non-ionic monomer which may be the same or different from the monomer i), v) one or more ethylenically unsaturated acid monomers which may be the same or different from the monomer ii), vi) optionally one or more ethylenically unsaturated crosslinking monomers, which may be the same or different from the crosslinking monomer iii), preferably different from the crosslinking monomer iii); wherein: at least one of the monomers i) or iv) comprises at least one C1-C20 alkyl (meth)acrylate, preferably at least one C1-C14 alkyl(meth)acrylate, more preferably at least one C1-C12 alkyl(meth)acrylate or C1-C10 alkyl(meth)acrylate, most preferably at least one of lauryl acrylate, lauryl methacrylate, ethyl acrylate, n-butyl acrylate, isobutyl acrylate, 2-methylbutyl acrylate, n- heptyl acrylate, or 2-octyl acrylate; and a weight ratio of the first stage polymer to the second stage polymer is from 95:5 to 55:45, preferably from 90: 10 to 60:40, preferably from 85: 15 to 65:35, more preferably from 80:20 to 70:30.

[0108] Aspect 2. The multistage aqueous emulsion polymer of Aspect 1, wherein the Tg of the second stage polymer is from less than -50°C to -70°C, as calculated according to the Fox equation.

[0109] Aspect 3. The multistage aqueous emulsion polymer of Aspect 1 , wherein at least one of the lauryl acrylate, lauryl methacrylate, ethyl acrylate, n-butyl acrylate, isobutyl acrylate, 2- methylbutyl acrylate, n-heptyl acrylate, or 2-octyl acrylate is biobased.

[0110] Aspect 4. The multistage aqueous emulsion polymer of Aspect 1 or Aspect 2, wherein the first stage polymer comprises 0.25-4wt%, or 0.4 to 3.5 wt%, or 0.5 to 3 wt%, or 0.5 to 2.5 wt% of the one or more ethylenically unsaturated acid monomers ii), based on a weight of the first stage polymer.

[0111] Aspect 5. The multistage aqueous emulsion polymer of any of Aspects 1-3, wherein the second stage polymer comprises 0.25-4wt%, or 0.4 to 3.5 wt%, or 0.5 to 3 wt% or 0.5 to 2.5 wt% of the one or more ethylenically unsaturated acid monomers v), based on a weight of the second stage polymer.

[0112] Aspect 6. The multistage aqueous emulsion polymer of any of Aspects 1-4, wherein the first stage polymer comprises 0.01-10 wt%, or 0.01-5 wt%, or 0.01-4 wt%, or 0.01-3 wt%, or 0.01- 2wt% of the at least one ethylenically unsaturated crosslinking monomer iii) in the first stage polymer, based on a weight of the first stage polymer.

[0113] Aspect 7. The multistage aqueous emulsion polymer of any of Aspects 1-5, wherein the second stage polymer comprisesO.01-10 wt%, or 0.01-5 wt%, or 0.01-4 wt%, or 0.01-3 wt%, or 0.01-2wt% of the vi) at least one ethylenically unsaturated crosslinking monomer, based on a weight of the second stage polymer.

[0114] Aspect 8. The multistage aqueous emulsion polymer of any of Aspects 1-6, wherein the monomer i) further comprises at least one of vinyl aromatic monomers, hydrocarbons having at least one free radical polymerizable C=C double bond, vinyl acetate, vinyl versatate, hydroxy (meth)acrylates, (meth)acrylonitrile, amide group-containing monomers, or combinations thereof preferably vinyl aromatic monomers, hydroxy (meth)acrylates, or combinations thereof.

[0115] Aspect 9. The multistage aqueous emulsion polymer of any of Aspects 1-7, wherein the monomer iv) further comprises at least one of hydrocarbons having at least one free radical polymerizable C=C double bond, vinyl aromatic monomers, vinyl versatate, vinyl acetate, hydroxy(meth)acrylates, (meth)acrylonitrile, amide group-containing monomers, or combinations thereof, preferably vinyl aromatic monomers, hydroxy (meth)acrylates, or combinations thereof.

[0116] Aspect 10. The multistage aqueous emulsion polymer of any of Aspects 1-8, wherein the monomer ii) comprises at least one of carboxylic acid-functionalized monomers, phosphorus acid- functionalized monomers, sulfur acid-functionalized monomers, phosphate acid-functionalized monomers, or combinations thereof, preferably (meth)acrylic acid, beta-carboxy ethyl acrylate, maleic acid, fumaric acid, itaconic acid, ethacrylic acid, crotonic acid, citraconic acid, cinnamic acid, vinyl phosphonic acid, or combinations thereof, more preferably acrylic acid, methacrylic acid, or combinations thereof.

[0117] Aspect 11. The multistage aqueous emulsion polymer of any of Aspects 1-9, wherein the monomer v) comprises at least one of carboxylic acid-functionalized monomers, phosphorus acid- functionalized monomers, sulfur acid-functionalized monomers, phosphate acid-functionalized monomers, or combinations thereof, preferably (meth)acrylic acid, beta-carboxyethyl acrylate, maleic acid, fumaric acid, itaconic acid, ethacrylic acid, crotonic acid, citraconic acid, cinnamic acid, vinyl phosphonic acid, or combinations thereof, more preferably acrylic acid, methacrylic acid, or combinations thereof

[0118] Aspect 12. The multistage aqueous emulsion polymer of any of Aspects 1-10, wherein the monomer iii) comprises at least one of hydroxyl functional monomers, keto functional monomers, epoxy functional monomers, monomers comprising two or more free radical polymerizable C-C double bonds, or combinations thereof, preferably hydroxyl functional monomers, keto functional monomers, monomers comprising two or more free radical polymerizable C-C double bonds, or combinations thereof, more preferably hydroxyl functional monomers, keto functional monomers, or combinations thereof.

[0119] Aspect 13. The multistage aqueous emulsion polymer of any of Aspects 1-11, wherein the monomer vi) comprises at least one of hydroxyl functional monomers, keto functional monomers, epoxy functional monomers, monomers comprising two or more free radical polymerizable C-C double bonds, or combinations thereof, preferably hydroxyl functional monomers, keto functional monomers, monomers comprising two or more free radical polymerizable C-C double bonds, or combinations thereof, more preferably hydroxyl functional monomers, keto functional monomers, or combinations thereof.

[0120] Aspect 14. A caulk composition comprising the multistage aqueous emulsion polymer of any of Aspects 1-13, wherein the caulk satisfies the ASTM C719-22 Class 35 test according to ASTM C920-18.

[0121] Aspect 15. A caulk composition comprising the multistage aqueous emulsion polymer of any of Aspects 1-13, wherein the caulk composition comprises substantially no to zero plasticizer and / or substantially no to zero polyurethane and the caulk satisfies the ASTM C719-22 Class 35 test according to ASTM C920-18.

[0122] Aspect 16. A caulk composition comprising the multistage aqueous emulsion polymer of any of Aspects 1-13, wherein the caulk composition comprises no intentionally added plasticizer and / or no intentionally added polyurethane and the caulk satisfies the ASTM C719-22 Class 35 test according to ASTM C920-18.

[0123] Aspect 17. The caulk composition of any of Aspects 14-16, further comprising at least one additive comprising at least one of: at least one surfactant, at least one rheology modifier, at least one freeze-thaw stabilizer, at least one adhesion promotor, or combinations thereof.

[0124] Aspect 18. The caulk composition of any of Aspects 14-17, further comprising 0 to 95 wt.% of a filler, wherein a weight ratio of a total amount of the filler to the multistage aqueous emulsion polymer is from 0:1 to 1 : 1.5.

[0125] Aspect 19. A multistage aqueous emulsion polymer comprising: a) a first stage polymer having a Tg from -10°C to -50°C, as calculated according to the Fox equation, comprising, as polymerized monomers: i) one or more ethylenically unsaturated non-ionic monomer: ii) 0.25-4wt% of one or more ethylenically unsaturated acid monomer based on a weight of the first stage polymer, iii) 0.01-2wt% of one or more ethylenically unsaturated crosslinking monomer based on a weight of the first stage polymer; and b) a second stage polymer having a Tg from less than -50°C to -70°C as calculated according to the Fox equation, comprising, as polymerized monomers: iv) one or more ethylenically unsaturated non-ionic monomer which may be the same or different from the monomer i), v) 0.25-4wt% of one or more ethylenically unsaturated acid monomers based on a weight of the second stage polymer which may be the same or different from the monomer ii), vi) 0.01-2wt% of at least one ethylenically unsaturated crosslinking monomer based on a weight of the second stage polymer which may be the same or different, preferably different from the crosslinking monomer iii); wherein: at least one of the monomers i) or iv) comprises at least one of lauryl acrylate, lauryl methacrylate, ethyl acrylate, n-butyl acrylate, isobutyl acrylate, 2-methylbutyl acrylate, n-heptyl acrylate, or 2-octyl acrylate; and a weight ratio of the first stage polymer to the second stage polymer is from 95:5 to 55:45, 90: 10 to 60:40, preferably from 85: 15 to 65:35, more preferably from 80:20 to 70:30.

[0126] Aspect 20. A caulk composition comprising the multistage aqueous emulsion polymer of Aspect 17, wherein the caulk is capable of satisfying ASTM C719-22 Class 35 test according to ASTM C920-18; wherein the caulk composition comprises substantially no to zero plasticizer and / or substantially no to zero polyurethane.

[0127] EXAMPLES

[0128] Example 1 : Preparation of a two stage polymer

[0129] 510 grams of deionized water and 2 grams of sodium dihexyl sulfosuccinate was charged into a reactor equipped with a stirrer, reflux condensers, thermocouples, and stainless steel feed lines. The reaction mixture was heated up to 81 °C. A first monomer emulsion including 100 grams of water, 14.5 grams of disodium succinate alkyl polyoxyethylene ether monoester sulfonate, 15 grams of ethoxylated tridecyl alcohol, 680 grams of 2-ethylhexyl acrylate, 9 grams of 2-hydroxyethyl acrylate, 179 grams of methyl methacrylate, and 17 grams of methacrylic acid, was added over the course of 197 minutes. At the same time, a solution of 3.7 grams of sodium bicarbonate, 7.5 grams of ammonium persulfate, and 60 grams of water was fed over the course of 262 minutes. After the first monomer emulsion had been completely fed into the reactor, a second monomer emulsion including 33 grams of water, 5 grams of disodium succinate alkyl polyoxyethylene ether monoester sulfonate, 5 grams of ethoxylated tridecyl alcohol, 256 grams of 2-ethylhexyl acrylate, 29 grams of 2-octyl acrylate, 3 grams of 2-hydroxyethyl acrylate and 5.8 grams of methacrylic acid, was fed over the course of 65 minutes. Then the reaction mixture was cooled to 70°C. A solution of tert-butyl hydroperoxide in water and a solution of sodium metabisulfite in water was fed concurrently over the course of 60 minutes. Then the reaction mixture was cooled to room temperature. The solids content of the dispersion was 59.2%. Example 2: Preparation of a two stage polymer with different crosslinkers in each stage

[0130] 510 grams of deionized water and 2 grams of sodium dihexyl sulfosuccinate was charged into a reactor equipped with a stirrer, reflux condensers, thermocouples, and stainless steel feed lines. The reaction mixture was heated up to 81 °C. A first monomer emulsion including 100 grams of water, 29 grams of disodium succinate alkyl polyoxyethylene ether monoester sulfonate, 680 grams of 2-ethylhexyl acrylate, 9 grams of 2-hydroxy ethyl acrylate, 179 grams of methyl methacrylate, 18 grams of 50% aqueous N-methylol acrylamide solution and 17 grams of methacrylic acid, was added over the course of 197 minutes. At the same time, a solution of 3.7 grams of sodium bicarbonate, 7.5 grams of ammonium persulfate, and 60 grams of water was fed over course of 262 minutes. After the first monomer emulsion had been completely fed into the reactor, a second monomer emulsion including 33 grams of water, 10 grams of disodium succinate alkyl polyoxyethylene ether monoester sulfonate, 286 grams of 2-ethylhexyl acrylate, 3 grams of diacetone acrylamide, 3 grams of 2-hydroxy ethyl acrylate, and 5.8 grams of methacrylic acid, was fed over the course of 65 minutes. Then the reaction mixture was cooled to 70°C. A solution of tert-butyl hydroperoxide in water and a solution of sodium formaldehyde sulfoxylate in water was fed concurrently over the course of 60 minutes. Then the reaction mixture was cooled to room temperature. A solution of adipic dihydrazide (1.5 grams) dissolved in water (84 grams) was added. The solids content of the dispersion was 58.5%.

[0131] Example 3 Sealant / caulk formulation preparation with Example 1 and Example 2 polymers

[0132] To a 1 -quart double planetary mixer were added the components in Table 1, in the sequence listed. Agitation was adjusted manually to achieve good mixing. After the addition of Ti-Pure, the mixture was stirred for 30 minutes before adding the rest of the components.

[0133] Table 1

[0134] Example 4 Class 35 Sealant Testing Procedure According to ASTM C719-22

[0135] Three 2” x 0.5” x 0.5” sealant samples derived from the same formulation of the caulk prepared using the Example 2 polymer as shown in Example 3 was cured between two aluminum plates at room temperature for 3 weeks. After curing, the samples were soaked in room temperature water for 1 week. The samples were compressed to 0.325” and placed in a 70°C oven for 1 week. Then the samples were subjected to 10 cycles of alternating extension / compression at room temperature. Each cycle consisted of extending the sample to 0.675” followed by compression to 0.325”. After this was complete, the samples were subjected to 10 cycles of alternating extension / compression. Each cycle consisted of extending the sample to 0.675” at - 26°C followed by compression to 0.325” at 70°C.

[0136] The sample is determined to have passed the Class 35 testing protocol if the total amount of delamination and / or cohesive failure of the caulk is less or equal to 1.5 square inches per ASTM Method C920-18 as measured by a ruler.???? Three comparative samples of commercial caulks made from acrylic polymers, not according to the present invention, are shown as Figure 1. As can be seen, all three of these caulks failed the ASTM C719-22 Class 35 testing protocol per ASTM Method C920-18. Figure 2 shows the caulk made using the inventive two stage polymer according to Example 2. As can be seen, this caulk composition passed the Class 35 testing protocol.

[0137] Within this specification embodiments have been described in a way which enables a clear and concise specification to be written, but it is intended and will be appreciated that embodiments may be variously combined or separated without departing from the invention. For example, it will be appreciated that all preferred features described herein are applicable to all aspects of the invention described herein.

[0138] The foregoing description of various forms of the invention has been presented for purposes of illustration and description. It is not intended to be exhaustive or to limit the invention to the precise forms disclosed. Numerous modifications or variations are possible in light of the above teachings. The forms discussed were chosen and described to provide the best illustration of the principles of the invention and its practical application to thereby enable one of ordinary skill in the art to utilize the invention in various forms and with various modifications as are suited to the particular use contemplated. All such modifications and variations are within the scope of the invention as determined by the appended claims when interpreted in accordance with the breadth to which they are fairly, legally, and equitably entitled.

Claims

What is claimed is:

1. A multistage aqueous emulsion polymer comprising: a) a first stage polymer having a Tg from -10°C to -50°C, as calculated according to the Fox equation, comprising, as polymerized monomers: i) one or more ethylenically unsaturated non-ionic monomer; ii) one or more ethylenically unsaturated acid monomer; iii) optionally one or more ethylenically unsaturated crosslinking monomer; and b) a second stage polymer having a Tg of less than the Tg of the first stage polymer, as calculated according to the Fox equation, comprising, as polymerized monomers: iv) one or more ethylenically unsaturated non-ionic monomer which may be the same or different from the monomer i), v) one or more ethylenically unsaturated acid monomers which may be the same or different from the monomer ii), vi) optionally one or more ethylenically unsaturated crosslinking monomers, which may be the same or different from the crosslinking monomer iii), preferably different from the crosslinking monomer iii); wherein: at least one of the monomers i) or iv) comprises at least one C1-C20 alkyl (meth)acrylate, preferably at least one Cl -Cl 4 alkyl(meth)acrylate, more preferably at least one Cl -Cl 2 alkyl(meth)acrylate or Cl -CIO alkyl (meth)acrylate, most preferably at least one of lauryl acrylate, lauryl methacrylate, ethyl acrylate, n-butyl acrylate, isobutyl acrylate, 2-methylbutyl acrylate, n-heptyl acrylate, or 2-octyl acrylate; and a weight ratio of the first stage polymer to the second stage polymer is from 95:5 to 55:45, preferably from 90: 10 to 60:40, preferably from 85: 15 to 65:35, more preferably from 80:20 to 70:30.

2. The multistage aqueous emulsion polymer of claim 1, wherein the Tg of the second stage polymer is from less than -50°C to -70°C, as calculated according to the Fox equation.

3. The multistage aqueous emulsion polymer of claim 1, wherein at least one of the lauryl acrylate, lauryl methacrylate, ethyl acrylate, n-butyl acrylate, isobutyl acrylate, 2-methylbutyl acrylate, n-heptyl acrylate, or 2-octyl acrylate is biobased.

4. The multistage aqueous emulsion polymer of claim 1 or claim 2, wherein the first stage polymer comprises 0.25-4wt%, or 0.4 to 3.5 wt%, or 0.5 to 3 wt%, or 0.5 to 2.5 wt% of the one or more ethylenically unsaturated acid monomers ii), based on a weight of the first stage polymer.

5. The multistage aqueous emulsion polymer of any of claims 1-3, wherein the second stage polymer comprises 0.25-4wt%, or 0.4 to 3.5 wt%, or 0.5 to 3 wt% or 0.5 to 2.5 wt% of the one or more ethylenically unsaturated acid monomers v), based on a weight of the second stage polymer.

6. The multistage aqueous emulsion polymer of any of claims 1-4, wherein the first stage polymer comprises 0.01-10 wt%, or 0.01-5 wt%, or 0.01-4 wt%, or 0.01-3 wt%, or 0.01-2wt% of the at least one ethylenically unsaturated crosslinking monomer iii) in the first stage polymer, based on a weight of the first stage polymer.

7. The multistage aqueous emulsion polymer of any of claims 1-5, wherein the second stage polymer comprises 0.01-10 wt%, or 0.01-5 wt%, or 0.01-4 wt%, or 0.01-3 wt%, or 0.01-2wt% of the vi) at least one ethylenically unsaturated crosslinking monomer, based on a weight of the second stage polymer.

8. The multistage aqueous emulsion polymer of any of claims 1-6, wherein the monomer i) further comprises at least one of vinyl aromatic monomers, hydrocarbons having at least one free radical polymerizable C-C double bond, vinyl acetate, vinyl versatate, hydroxy (meth)acrylates, (meth)acrylonitrile, amide group-containing monomers, or combinations thereof preferably vinyl aromatic monomers, hydroxy (meth)acrylates, or combinations thereof.

9. The multistage aqueous emulsion polymer of any of claims 1-7, wherein the monomer iv) further comprises at least one of hydrocarbons having at least one free radical polymerizable C-C double bond, vinyl aromatic monomers, vinyl versatate, vinyl acetate, hydroxy(meth)acrylates, (meth)acrylonitrile, amide group-containing monomers, or combinations thereof, preferably vinyl aromatic monomers, hydroxy (meth)acrylates, or combinations thereof.

10. The multistage aqueous emulsion polymer of any of claims 1-8, wherein the monomer ii) comprises at least one of carboxylic acid-functionalized monomers, phosphorus acid- functionalized monomers, sulfur acid-functionalized monomers, phosphate acid-functionalized monomers, or combinations thereof, preferably (meth)acrylic acid, beta-carboxyethyl acrylate, maleic acid, fumaric acid, itaconic acid, ethacrylic acid, crotonic acid, citraconic acid, cinnamic acid, vinyl phosphonic acid, or combinations thereof, more preferably acrylic acid, methacrylic acid, or combinations thereof.

11. The multistage aqueous emulsion polymer of any of claims 1-9, wherein the monomer v) comprises at least one of carboxylic acid-functionalized monomers, phosphorus acid- functionalized monomers, sulfur acid-functionalized monomers, phosphate acid-functionalized monomers, or combinations thereof, preferably (meth)acrylic acid, beta-carboxyethyl acrylate, maleic acid, fumaric acid, itaconic acid, ethacrylic acid, crotonic acid, citraconic acid, cinnamic acid, vinyl phosphonic acid, or combinations thereof, more preferably acrylic acid, methacrylic acid, or combinations thereof.

12. The multistage aqueous emulsion polymer of any of claims 1-10, wherein the monomer iii) comprises at least one of hydroxyl functional monomers, keto functional monomers, epoxy functional monomers, monomers comprising two or more free radical polymerizable C-C double bonds, or combinations thereof, preferably hydroxyl functional monomers, keto functional monomers, monomers comprising two or more free radical polymerizable C-C double bonds, or combinations thereof, more preferably hydroxyl functional monomers, keto functional monomers, or combinations thereof.

13. The multistage aqueous emulsion polymer of any of claims 1-11, wherein the monomer vi) comprises at least one of hydroxyl functional monomers, keto functional monomers, epoxy functional monomers, monomers comprising two or more free radical polymerizable C-C double bonds, or combinations thereof, preferably hydroxyl functional monomers, keto functional monomers, monomers comprising two or more free radical polymerizable C-C double bonds, or combinations thereof, more preferably hydroxyl functional monomers, keto functional monomers, or combinations thereof.

14. A caulk composition comprising the multistage aqueous emulsion polymer of any of claims 1-13, wherein the caulk satisfies the ASTM C719-22 Class 35 test according to ASTM C920-18.

15. A caulk composition comprising the multistage aqueous emulsion polymer of any of claims 1-13, wherein the caulk composition comprises substantially no to zero plasticizer and / or substantially no to zero polyurethane and the caulk satisfies the ASTM C719-22 Class 35 test according to ASTM C920-18.

16. A caulk composition comprising the multistage aqueous emulsion polymer of any of claims 1-13, wherein the caulk composition comprises no intentionally added plasticizer and / or no intentionally added polyurethane and the caulk satisfies the ASTM C719-22 Class 35 test according to ASTM C920-18.

17. The caulk composition of any of claims 14-16, further comprising at least one additive comprising at least one of: at least one surfactant, at least one rheology modifier, at least one freeze-thaw stabilizer, at least one adhesion promotor, or combinations thereof.

18. The caulk composition of any of claims 14-17, further comprising 0 to 95 wt.% of a filler, wherein a weight ratio of a total amount of the filler to the multistage aqueous emulsion polymer is from 0:1 to 1 : 1.5.

19. A multistage aqueous emulsion polymer comprising: a) a first stage polymer having a Tg from -10°C to -50°C, as calculated according to the Fox equation, comprising, as polymerized monomers: i) one or more ethylenically unsaturated non-ionic monomer: ii) 0.25-4wt% of one or more ethylenically unsaturated acid monomer based on a weight of the first stage polymer, iii) 0.01-2wt% of one or more ethylenically unsaturated crosslinking monomer based on a weight of the first stage polymer; and b) a second stage polymer having a Tg from less than -50°C to -70°C as calculated according to the Fox equation, comprising, as polymerized monomers: iv) one or more ethylenically unsaturated non-ionic monomer which may be the same or different from the monomer i), v) 0.25-4wt% of one or more ethylenically unsaturated acid monomers based on a weight of the second stage polymer which may be the same or different from the monomer ii), vi) 0.01-2wt% of at least one ethylenically unsaturated crosslinking monomer based on a weight of the second stage polymer which may be the same or different, preferably different from the crosslinking monomer iii);wherein : at least one of the monomers i) or iv) comprises at least one of lauryl acrylate, lauryl methacrylate, ethyl acrylate, n-butyl acrylate, isobutyl acrylate, 2-methylbutyl acrylate, n-heptyl acrylate, or 2-octyl acrylate; and a weight ratio of the first stage polymer to the second stage polymer is from 95:5 to 55 :45, 90: 10 to 60:40, preferably from 85: 15 to 65:35, more preferably from 80:20 to 70:30.

20. A caulk composition comprising the multistage aqueous emulsion polymer of claim 17, wherein the caulk is capable of satisfying ASTM C719-22 Class 35 test according to ASTM C920-18; wherein the caulk composition comprises substantially no to zero plasticizer and / or substantially no to zero polyurethane.

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