BIO-based polymeric binder

Abstract

An aqueous polymer emulsion including, as polymerized monomers: a) at least one ethylenically unsaturated monomer of structure (I) where the structure I has at least 63% biocarbon content determined by ASTM 6866-22 Method B; b) an aryl-containing ethylenically unsaturated monomer, a C2-C6 ethylenically unsaturated monomer, or a combination thereof; c) a phosphorus-containing free-radical polymerizable monomer, different from monomer a) and monomer b); d) optionally, a free radical polymerizable monomer, including a beta dicarbonyl functionality; e) optionally, a free radical polymerizable polyethylenically unsaturated monomer; wherein the polymer: includes at least 22% biocarbon content determined by ASTM 6866-22 Method B; and has a minimum film forming temperature of less than 30°C as determined by ASTM D2354-10.

Description

[0001] BIO-BASED POLYMERIC BINDER

[0002] FIELD OF THE INVENTION

[0003] The invention relates to a bio-based aqueous polymeric emulsion binder for industrial coatings and an industrial coating prepared from the polymeric emulsion binder. The coating is especially useful for direct-to-metal coating applications whereby the direct-to-metal coating is applied directly to a metal surface and can adhere without the need for a primer coating / layer. The direct-to-metal coatings prepared from / using the bio-based polymeric emulsion binders of this invention provide the protection of a primer with the desirable appearance and performance properties of a topcoat. As a result, the use of such direct-to-metal coatings is more efficient, requires fewer application steps and less labor, thereby reducing costs.

[0004] BACKGROUND

[0005] Coatings containing acrylic emulsion polymers are commonly used in architecture, industry, and construction for a variety of uses due to their good balance of performance and cost.

[0006] One way to reduce petroleum-sourced content in acrylic emulsion polymers is to add biobased materials via a blending approach. However, it is well known in the art that most polymer pairs are chemically incompatible. This inherent incompatibility often results in performance deterioration, rather than desired synergistic performance benefits.

[0007] To increase the bio-carbon content of the acrylic polymer while maintaining or improving the performance of resulting coating compositions, an alternative approach, yet more difficult to execute, is to polymerize acrylic monomers containing a certain degree of bio-renewable content. The challenge lies in producing an acrylic polymer from available biobased acrylic monomers while simultaneously achieving the performance required by the intended application and the added sustainability target of a minimum biocarbon content (BCC) threshold of 22%.

[0008] Industrial coatings, especially those intended for direct-to-metal (DTM) applications, have a particularly stringent set of requirements for use, including the necessity of protecting a metal substrate from weather and / or corrosive environments. In addition, these coatings should be able to pass adhesion testing, have a good Konig harness, be suitably hydrophobic to protect the metal substrate from water, especially salt water, be resistant to UV weather testing, and to have good hardness and gloss.

[0009] US 10662273 relates to waterborne acrylic dispersions with biorenewable content and use thereof in coating compositions, particularly in paints and plasters.

[0010] US 9593191 relates to the use of a polymer from the polymerization of 2-octyl acrylate of renewable origin and optionally at least one other monomer, as a binding agent in the production of a coating composition.

[0011] US 9505943 relates to an aqueous polymer coating composition including a vinyl polymer A; and a vinyl polymer B such that at least 20 wt % of at least one of polymer A and or polymer B is derived from at least one bio-renewable olefmically unsaturated monomer.

[0012] US 9458346 relates to an aqueous polymer dispersion including a vinyl polymer with at least two phases comprising: A) a vinyl polymer A having a glass transition temperature in the range of from 50 to 30° C.; and B) a vinyl polymer B having a glass transition temperature the range of from 50 to 130° C.; and at least 20 wt % of the monomer composition used to form vinyl polymer A and vinyl polymer B is derived from at least one bio-renewable olefmically unsaturated monomer

[0013] US 8889783 relates to copolymers including a vinyl aromatic monomer; a second monomer, and a biobased monomer.

[0014] US 2021 / 0324114 relates to an aqueous dispersion as a biobased binder and an aqueous coating composition including the aqueous dispersion and showing balanced stain resistance, freeze-thaw stability, and anti-clogging properties.

[0015] CN 112300343 relates to a bio-based acrylate emulsion for building interior wall coating and a preparation method thereof.

[0016] EP 2626397 relates to a pressure-sensitive adhesive including an acrylate-based polymer component, such that at least 50 wt% of the monomers used for preparing the polymer component are in each case fully biobased.

[0017] WO 2022 / 033945 relates to an aqueous vinyl polymer dispersion PD including a hydrophilic vinyl oligomer, a hydrophobic vinyl oligomer and a vinyl polymer obtained by the emulsion polymerization of ethylenically unsaturated monomers from petrochemical or renewable origin.

[0018] SUMMARY

[0019] This invention relates to biobased styrene acrylic latex coating compositions which achieve similar, comparable, or even better performances (including gloss, hardness, adhesion, weatherability and corrosion resistance) to commercially available petroleum-based industrial coatings, while at the same time having a relatively substantial / high bio carbon content.

[0020] According to an aspect of the invention, an aqueous polymer emulsion is provided, comprising, consisting of, or consisting essentially of polymer and water, where the polymer comprises, consists of, or consists essentially of, as polymerized monomers, the following monomers a), b), c), d), and e). The amounts are recited in wt%, based on a total dry weight of the polymer. a) 20-70%, by weight of the polymer, of at least one ethylenically unsaturated monomer of structure (I) where R1is hydrogen or a methyl group and R2is a C6-C8 non-cyclic alkyl group, wherein the structure I has at least 63% biocarbon content as determined by ASTM 6866-22 Method B; b) 30-80%, by weight of the polymer, of an aryl-containing ethylenically unsaturated monomer, a C2-C6 ethylenically unsaturated monomer, or a combination thereof; c) 0.1 to 1.9 %, by weight of the polymer, of at least one phosphorus-containing free-radical polymerizable monomer, different from monomer a) or monomer b); d) 0 to 10 %, by weight of the polymer, of a free radical polymerizable monomer, different from monomer a), monomer b), and monomer c), comprising a beta dicarbonyl functionality; e) 0 to 1.9 %, by weight of the polymer, of a free radical polymerizable polyethylenically unsaturated monomer different from a), b), c), and d).

[0021] According to an embodiment, the polymer may include at least 22% biocarbon content as determined by ASTM 6866-22 Method B. According to an embodiment, the polymer has a minimum fdm forming temperature of less than 30°C as determined by ASTM D2354-10.

[0022] Coatings comprising the aqueous polymer are also provided. Upon drying, dried coating may exhibit one or more of the following properties:

[0023] Konig hardness of 9 seconds or more as measured according to ASTM 4366-16; passes humidity testing according to ASTM D714-02; and / or no blistering under corrosion resistance testing according to ASTM Bl 17-19.

[0024] BRIEF DESCRIPTION OF THE DRAWINGS

[0025] Figure 1 shows clear film water absorption of an embodiment of the present invention compared to two comparative examples.

[0026] Figure 2 shows the results of Electrochemical Impedance Spectroscopy (E.I.S.) of an embodiment of the present invention compared to two comparative examples and a commercial sample.

[0027] Figure 3 shows 216-hour salt fog corrosion resistance properties of an embodiment of the present invention compared to two comparative examples and a commercial sample.

[0028] Figure 4 shows QUV gloss retention results of an embodiment of the present invention compared to two comparative examples and a commercial sample.

[0029] Figure 5 shows 200-hour salt fog corrosion resistance properties of four comparative examples. DETAILED DESCRIPTION

[0030] The terms “bio-based” or “biobased” as used herein refer to 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, or polymers, containing any amount of bio-based content are referred to as “bio-based.”

[0031] The terms, “non-bio-based” or “non-biobased” as used herein refer to any product that does not contain any bio-based materials. For example, products made entirely from petrochemical resources are referred to as non-bio-based products.

[0032] Percent biocarbon content (BCC) or biobased (or bio-based) content is a measure of the amount of biomass-derived carbon in a product as compared to its total organic carbon content (TOC). Percent biocarbon content is measured according to ASTM D6866-22, Method B. The biocarbon content of a product is reported as a fraction of the total organic carbon content (TOC) and not on its weight according to ASTM D6866-22 Method B.

[0033] Unless otherwise indicated, all percentages herein are weight percentages.

[0034] “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.

[0035] The term “polymer” encompasses homopolymers, as well as polymers prepared from two or more different monomers.

[0036] 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.

[0037] The terms “comprise” or “include” as used herein encompass “consist”, and “consist essentially of.” BCC content of the polymer

[0038] According to an embodiment, the polymer includes at least 22% biocarbon content as determined by ASTM 6866-22 Method B. According to some embodiments, the polymer includes at least 22, 25, 30, 35, 40, 45, 50, 55, 60, 65, 70, 75, 80, 85, 90, 95, 99 or up to 100 % BCC as determined by ASTM D6866-22 Method B.

[0039] Properties of the polymer

[0040] An aqueous emulsion of the polymer may have a minimum film formation temperature of less than 30°C as measured according to ASTM D2354-10(2018). According to some embodiments, the aqueous emulsion of the polymer may have a minimum film formation temperature of less than 25, 20, 15, 10, 5, or less than 0°C.

[0041] According to some embodiments, the polymer may be a single stage polymer excluding a seed polymer. According to some other embodiments, the polymer may be a two stage polymer, each stage having a different composition, excluding a seed polymer. According to other embodiments, the polymer may be a multi-stage polymer, i.e. including three or more stages, each stage having a different composition, excluding a seed polymer. According to some embodiments, the polymer may include two or more stages, excluding a seed polymer.

[0042] According to an embodiment, the polymer may have a single Tg or two or more Tg’s as measured by differential scanning calorimetry (DSC).

[0043] According to some embodiments, at least one Tg of the polymer may be less than 25, 20, 15, 10, 5, or less than 0°C, as calculated by the Fox equation. The Fox equation provides an estimate for glass transition temperature of a polymer based on a weighted average of the glass transition temperatures of homopolymers of each monomer in the polymer. The Fox equation for polymer having n monomers is:

[0044] 1 / Tg(polymer)={fi / Tgi} + {fz / Tgz} + {fs / Tgs} +....+ {fn / Tgn} where: Tg(polymer) is the calculated Tg of the polymer and Tgi, Tg2, Tg3, ... Tgnare the respective Tg’s of homopolymers of the monomers 1, 2, 3, ...n, each of which’s weight fraction in the polymer is fi , f2, fi, .. ,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.

[0045] According to an embodiment, the total percentages of the monomers a), b), c), and optionally additional monomers d) and / or e) in the polymer may add up to 100%.

[0046] Monomers in the polymer

[0047] Monomer a)

[0048] The polymer includes 20-70% by weight of the polymer of at least one ethylenically unsaturated monomer a) having structure (I), where R1is hydrogen or a methyl group and R2is a C6-C8 non-cyclic alkyl group, where the structure (I) includes at least 63% biocarbon content as determined by ASTM 6866-22 Method B.

[0049] According to an embodiment, the monomer a) comprises, consists of, or consists essentially of 2-ethyl hexyl (meth)acrylate, n-heptyl(meth)acrylate, 2-octyl acrylate, 2-octyl methacrylate, or combinations thereof; most preferably 2-octyl acrylate or 2-ethyl hexyl acrylate.

[0050] According to some embodiments, the polymer may comprise at least 20, 25, 30, 35, 40, 45, 50, 55, 60, or at least 65 wt% of the monomer a) or a mixture of monomers a) based on the total weight of the polymer. According to some embodiments, the polymer includes at most 70, 65, 60, 55, 50, 45, 40, 35, 30, or at most 25 wt% of monomer(s) a) based on the total weight of the polymer. According to some embodiments, the polymer includes from 25-65, or from 30-60, or from 40-60, or from 50-70 wt% of the monomer(s) a) based on the total weight of the polymer. Monomer b)

[0051] The polymer also includes 30-80% of monomer b) by weight of the polymer. Monomer b) comprises, consists of, or consists essentially of an aryl-containing ethylenically unsaturated monomer, a C2-C6 ethylenically unsaturated monomer, or a combination thereof;

[0052] According to an embodiment, monomer b) comprises at least one ethylenically unsaturated aromatic monomer, at least one C1-C5 (meth)acrylate, or a combination thereof; preferably styrene or a derivative thereof, methyl (meth)acrylate or ethyl (meth)acrylate, or a combination thereof, more preferably styrene and / or methyl methacrylate, most preferably styrene.

[0053] According to some embodiments, the polymer may comprise at least 30, 35, 40, 45, 50, 55, 60, 65, 70, or at least 75 wt% of the monomer b) or a mixture of monomers b) based on the total weight of the polymer. According to some embodiments, the polymer includes at most 80, 75, 70, 65, 60, 55, 50, 45, 40, or at most 35 wt% of monomer(s) b) based on the total weight of the polymer. According to some embodiment, the polymer includes 30-75, 30-65, 30-55, or 30-45 wt% of monomer(s) b) based on the total weight of the polymer.

[0054] Monomer c)

[0055] The polymer includes 0.1 to 1.9 wt% of at least one phosphorus-containing free-radical polymerizable monomer, different from monomer a) or monomer b), based on the total weight of the polymer. According to some embodiments, the polymer may include 0.1-1.5, 0.2-1.3, or 0.5- lwt% of at least one phosphorus-containing free-radical polymerizable monomer, different from monomer a) and monomer b), based on the total weight of the polymer. According to some embodiments the polymer includes 0.1-1.9, 0.2-1.9, or 0.5-1.9wt% of at least one phosphorus- containing free-radical polymerizable monomer, different from monomer a) and monomer b), based on the total weight of the polymer.

[0056] According to an embodiment, the monomer c) comprises at least one of phosphoalkyl (meth)acrylates; phosphoalkyl (meth)acrylamides; phosphoalkyl crotonates, phosphoalkyl maleates, phosphoalkyl fumarates, phosphodialkyl (meth)acrylates, phosphodialkyl crotonates, vinyl phosphates or (meth)allyl phosphate; phosphate esters of polypropylene glycol mono(meth)acrylate or polyethylene glycol mono(meth)acrylate; polyoxyethylene allyl ether phosphate, vinyl phosphonic acid, or combinations thereof; preferably phosphoalkyl (meth)acrylates; polypropylene glycol mono(meth)acrylate or polyethylene glycol mono(meth)acrylate, or combinations thereof; more preferably phosphoalkyl (meth)acrylates, or combinations thereof.

[0057] Monomer d)

[0058] The polymer includes 0 to 10 wt% of a free radical polymerizable monomer d), comprising a beta dicarbonyl functionality, based on the total weight of the polymer.

[0059] According to some embodiments, the polymer may comprise from 0.1 to 10wt%, preferably from 0.5 to 6wt%, more preferably from 1 to 4wt% of monomer d) based on the total weight of the polymer. According to some embodiments, the polymer may comprise from 0.1 to 10%, preferably from 0.5 to 8%, more preferably from 1 to 6wt% of monomer d), by weight of the polymer. For example, the polymer may include at least 0.1, 0.5, 1, 1.5, 2, 3, 4, 5, 6, 7, 8, or at least 9 wt% of monomer d) by weight of the polymer. The polymer may include at most 10, 9, 8, 7, 6, 5, 4, 3, 2.5, 2, 1, 1.5, 1, or at most 0.5 wt% of monomer d) based on the total weight of the polymer.

[0060] According to an embodiment, monomer d), if present, comprises at least one 1,3- dicarbonyl group, preferably comprising diacetone acrylamide, acetoacetoxyethyl methacrylate (AAEM), or combinations thereof; more preferably aceto acetoxy ethyl methacrylate.

[0061] Monomer e)

[0062] The polymer includes 0 to 1.9 wt% of a free radical polymerizable polyethylenically unsaturated monomer e) different from a), b), c), and d), based on the total weight of the polymer.

[0063] According to some embodiments, the polymer may comprise from 0 to 1.9 wt% of monomer e), preferably from 0 to 1.5wt%, more preferably from 0 to 1 wt% of monomer e), based on the total weight of the polymer. According to some embodiments the polymer may comprise from 0.01 to 1.9% of monomer e) or from 0.05 to 1.5 % of monomer e), or from 0.1 to 1 wt% of monomer e), by weight of the polymer.

[0064] For example, the polymer may include at least 0.00, 0.01, 0.05, 0.1, 0.15, 0.2, 0.25, 0.3, 0.4, 0.5, 0.6, 0.7, 0.8, 0.9, 1, 1.1, 1.2, 1.3, 1.4, 1.5, 1.6, 1.7, or at least 1.8wt% of monomer e) by weight of the polymer. The polymer may include at most 1.9, 1.8, 1.7, 1.6, 1.5, 1.4, 1.3, 1.2, 1.1, 1 , 0.9, 0.8, 0.7, 0.6, 0.5, 0.4, 0.3, 0.2, 0.1 , or at most 0wt% of monomer e) based on the total weight of the polymer.

[0065] According to an embodiment, the monomer e), if present, comprises at least one monomer comprising two or three unsaturated carbon-carbon double bonds capable of being free- radical polymerized, or a combination thereof; preferably 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 dimethacrylate, diethylene glycol dimethacrylate, trimethylolpropane tri(meth)acrylate, 1,3-butyleneglycol dimethacrylate, 1,4- butyleneglycol dimethacrylate, dipentaerythritol pentaacrylate, pentaerythritol tetraacrylate, 1,10-decanediol diacrylate, ethoxylated (2) bisphenol A diacrylate, 1,3 -propanediol dimethacrylate, 1,4-butanediol diacrylate, 1 ,4-butanediol dimethacrylate, 1 ,6-hexanediol diacrylate, 1,6 hexanediol dimethacrylate, dially phthalate, allyl methacrylate, divinylbenzene, or a combination thereof, more preferably divinylbenzene, 1 ,6-hexanediol diacrylate, allyl methacrylate, or a combination thereof.

[0066] According to some embodiments the polymer does not comprise substantial amounts of polymerizable acidic monomers as a polymerized monomer. For example, the polymer may not include substantial amounts of (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, unsaturated C3-C6 monocarboxylic acids, e.g., monoesters of unsaturated C4-C6 dicarboxylic acids such as mono-methylmaleate or mono-ethylmaleate, or combinations thereof as a polymerized monomer(s). The presence of the acidic monomers may be detected by infrared spectroscopy and comparison to known standards.

[0067] Polymerization Methods:

[0068] The aqueous emulsion of the present invention comprises one or more emulsion polymers prepared by emulsion polymerization as is well known in the art.

[0069] The emulsion polymer may be prepared by emulsion polymerization of a mixture of monomers comprising the monomers a), b), c), optionally d), and optionally e) described above. 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 emulsion polymer. A monomer emulsion containing all or some portion of the monomers to be polymerized may be prepared using the monomers, water and surfactants.

[0070] The emulsion polymer may be prepared as a single stage or as a multistage polymer.

[0071] One or more surfactants may be added prior to, during, or after the polymerization of the monomer mixture, or combinations thereof. 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 Emulan®, Rhodasurf®, Tergitol™, Abex®, Disponil®, Emulgen, Ethal®, and Pluronic™. They include, for example, C4 to C12 mono-, di-, and tri-alkylphenols ethoxylates (EO range 3 to 70), C8 to Cl 8 fatty alcohol ethoxylates, Cl 1-C15 oxo-process alcohol ethoxylates, C16 to C18 fatty alcohol ethoxylates, Cl 1 oxo-process alcohol ethylates, C13 oxo-process alcohol ethoxylates. Some of the 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, Rhodacal® DS-4 and Rhodacal® A-246 / L 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 Polystep® P-H, 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 0.2 to 2%, by weight based on the total weight of monomer quantity.

[0072] As mentioned above, also suitable as stabilizers for the present emulsions are copolymerizable nonionic and anionic surfactants such as those disclosed in US2014 / 0243552, which is incorporated by reference herein. Other suitable copolymerizable surfactants are sold under the trade names Hitenol® BC, HitenoT® KH, Hitenol® AR, Adeka Reasoap SR and Adeka Reasoap ER, Oximulsion® React.

[0073] 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. 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.

[0074] The temperature suitable for the 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. In another aspect of the present invention 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, as noted above.

[0075] Additives in the aqueous emulsion:

[0076] According to some embodiments, the aqueous emulsion may further include biocides, preservatives, pigments, defoamers, photo initiators, stabilizers, rheology modifiers, pH adjustment agents, UV stabilizers, coalescing agents, antioxidants, antifoaming agents, solvents, rheology modifiers, or combinations thereof. According to embodiments, some or all of these additives may be completely or partially biobased. Coating composition

[0077] A coating composition is also provided. The coating composition includes the aqueous polymeric emulsion including the at least one polymer formed by emulsion polymerization of a monomer mixture including, based on a total dry weight of the polymer, monomers a), b), c), d), and e).

[0078] BCC content of the coating composition

[0079] The BCC of the coating composition is measured according to ASTM-6866-22 Method B. According to some embodiments, the coating composition includes at least 5, 10 15, 20, 22, 25, 30, 35, 40, 45, 50, 60, 65, 70, 75, or at least 80% BCC as measured according to ASTM- 6866-22 Method B.

[0080] According to an embodiment, the BCC of the coating composition is based on all of the organic carbons in the coating composition, i.e., carbons from the binder and carbons from any further additives to the coating composition.

[0081] According to another embodiment, the BCC of the coating composition is based on only the carbons from the binder in the coating composition.

[0082] Properties of the coating composition:

[0083] According to an embodiment, a coating comprising the aqueous polymer emulsion of the present invention in dried form, has one or more, preferably at least two and most preferably each of the following properties:

[0084] Konig hardness of 9 seconds or more as measured according to ASTM 4366-16; passes humidity testing according to ASTM D714-02; and / or no blistering under corrosion resistance testing according to ASTM Bl 17-19.

[0085] Other components in the coating composition:

[0086] The aqueous coating composition may further include other components (additives) in addition to the polymer emulsion. According to embodiments, some or all of these additional components may be completely or partially biobased. Such additives include but are not limited to, crosslinking agents, pH adjustment agents, UV stabilizers, foam control agents, wetting agents, fillers, pigments, pigment extenders, , dyes, matting and texturing agents, pigment enhancers, emulsifiers, surfactants, dispersants, curing agents, coalescents, wetting agents, biocides, thickeners, rheology modifiers, plasticizers, waxes, antifoaming agents, antisettling agents, antiskinning agents, corrosion inhibitors, dehydrators, antigassing agents, dispersion aids, driers, antistatic additives, flash corrosion inhibitors, floating and flooding additives, in-can and in-film preservatives, insecticidal additives, optical whiteners, reodorants, water-soluble resins and other agents used in the art. These include, tints, emulsifiers, rheology control additives, additional polymers, pigments or colorants, fillers, dispersants or surfactants, plasticizers, defoamers, thickeners, biocides, solvents, rheology modifiers, wetting or spreading agents, leveling agents, conductive additives, thermal insulating fillers, adhesion promoters, anti-blocking agents, anti-cratering agents or anti-crawling agents, corrosion inhibitors, anti-static agents, flame retardants, optical brighteners, UV absorbers or other light stabilizers, antioxidants, chelating agents, flattening agents, humectants, insecticides, lubricants, odorants, oils, waxes or anti-slip aids, soil repellants, freeze-thaw and / or open time additives, and stain resistant agents.

[0087] Non-limiting examples of pigments that can act as colorants, fillers or dyes include but are not limited to: carbon black, colored organic pigments, and metal oxide pigments, such as titanium dioxide, zinc oxide, clay, aluminum silicate, zinc hydroxide, magnesium silicate, calcium silicate, amorphous silica, vapor phase silica, fumed silica, colloidal silica, alumina, aluminum hydroxide, zirconium oxide, and cerium oxide, as well as calcium carbonate, magnesium carbonate, kaolin, clay, talc, calcium sulfate, barium sulfate, and zinc carbonate.

[0088] Pigments include colored and opacifying pigments. Pigment volume concentration is used in an amount of less than 50 volume percent based on dry components of the coating composition. Pigment volume concentration = volume of pigment / volume of total solids.

[0089] Colored pigments are finely ground natural or synthetic, insoluble particles used to impart color when added to paints and coatings compositions. Pigment refers to a class of organic or inorganic matter that is insoluble in water, not soluble in the use of media, but has been highly dispersed so that the colored matter is colored. Pigments used for coatings are well known in the art. Non limiting examples of pigments include anatine, brookite, cadmium yellow, cadmium red, cadmium green, orange cobalt, cobalt blue, cerulean blue, aureolin, cobalt yellow, copper pigments, azurite, Han purple, Han blue, Egyptian blue, malachite, Paris green, phthalocyanine blue BN, phthalocyanine green G, verdigris, viridian, iron oxide pigments, sanguine, caput mortuum, oxide red, red ochre, Venetian red, Prussian blue, clay earth pigments, yellow ochre, raw sienna, burnt sienna, raw umber, burnt umber, marine pigments (e.g., ultramarine, and ultramarine green shade), and zinc pigments (e.g., zinc white, and zinc ferrite).

[0090] Opacifying pigments reflect light and are used to make a coating opaque or less transparent. They prevent light transmission and provide ideal brightness and whiteness to the end product. The most commonly used are titanium dioxide (TiO2), barium sulphate, zinc oxide, calcium carbonate, talc, nepheline syenite and combinations thereof. The most common and preferred is TiO2. Extenders can also be added to the formulation. Suitable examples of extenders include precipitated grades of calcium carbonate, directly mined calcium carbonates, clean grades of magnesium calcium carbonate (dolomite), clean grades of calcined, pulverized clays (aluminosilicates), and clean purified grades of magnesium silicate.

[0091] A coalescing agent may be a component of the coating composition. As the coating dries after being applied to a substrate, the purpose of the coalescent agent in these compositions is to aid the discrete particles of polymer that are present in the aqueous emulsion to form into a continuous film. Coalescent works by softening the polymer particles, allowing them to fuse into a tough, continuous film. Common coalescing agents include ester alcohols, esters, and glycol ethers, esters, alcohols, amides, and polymers.

[0092] According to an embodiment, the coating composition may contain a water soluble or water dispersible latent crosslinking agent, as discussed above. According to some embodiments, this crosslinking agent is added when formulating the coating agent, rather than, or addition to, being added in to the aqueous emulsion of the polymer binder.

[0093] In an embodiment, the coating composition described herein further comprises one or more additives to improve surface characteristics of dry coatings. Nonlimiting examples include waxes, fluorosurfactants, silicone surfactants, Rhamnolipid-based surfactants, alcohol phosphate ester surfactants. These performance additives are commercially available, for example, under the name Capstone™, Aquacer®, Dowsil™, Stepcote®. Commonly used fluorosurfactants include, for example, fluoralkanes, perfluoralkanes, their derivatives, and the like. In an aspect, short chain fluorinated compounds are preferred. In a preferred aspect, the fluorosurfactant is an anionic C6-fluorocarbon compound (e.g., Capstone™ FS-61), and is preferably substantially free of PFOS (perfluorooctyl sulfonate) and PFOA (perfluorooctanoic acid). Wax additives which can come from both fossil and renewable sources, are often included in aqueous emulsions and coatings to improve water repellency, surface slip and block resistance. Nonlimiting examples include paraffin-based wax emulsions (e.g., Aquacer 497 and Aquacer 539 from BYK, Michem® Emulsion 36840 from Michelman, Joncryl® Wax 35 from BASF). Examples of silicone surfactants may include DOWSIL™ 21 IS Additive from Dow. Examples of alcohol phosphate ester surfactants include Stepcote® W-877, W-839 and W-843 from Stepan. Stepcote® W-877 is most preferred. The additive used is usually from 50 ppm to 5000 ppm based on the total weight of aqueous emulsion, from 100 to 4000 ppm, preferably from 200 to 3000 ppm, most preferably from 250 to 2500 ppm.

[0094] The coating composition may further comprise one or more of the surfactants discussed in the section on polymerization.

[0095] Uses

[0096] The coating compositions of the present invention may be applied by conventional techniques, such as dipping, brushing, flowing, or spraying onto a variety of substrate surfaces. The substrates may include without limitation, wood, fabricated wood, paper, cardboard, textiles, synthetic resins, ceramics, ferrous metals, non-ferrous metals, stone, concrete, plaster, and the like. As mentioned above, the coating composition is especially suitable for direct to metal applications. Non-limiting examples of suitable metal substrates are aluminum, cold rolled steel, hot rolled steel, and galvanized steel.

[0097] The coating compositions of the present invention may be used in indoor or outdoor applications. Useful applications may include, without limitation, interior and exterior wall coatings, garage floor coating, metal coating, rail car coating, agricultural machinery coating, automobile parts coating, log cabin coatings, deck stains, concrete coating, wood stains, porch or deck coatings, glossy top coats, traffic paints, kitchen cabinetry coatings, automobile refinish, lawn and garden equipment coatings, bus and truck top coatings, gloss trim enamels, metal primers, light duty maintenance coatings, furniture coatings, stain blocking coatings, appliance coatings, dumpster coatings, heavy duty equipment coatings, industrial equipment coatings, and sash and trim enamels.

[0098] The aqueous emulsion may be formulated into paints (coating compositions) of various colors when pigment is included. The coating composition may form a film on a substrate with or without the aid of coalescing agents when applied on the substrate at ambient conditions.

[0099] Coated substrate:

[0100] A coated substrate comprising the coating where the substrate comprises a metal. Nonlimiting examples of metal substrates are iron, brass, zinc, copper, tin, cold rolled steel, hot rolled steel, galvanized steel, aluminum, or combinations thereof. The metal substrate may be treated or untreated, and may be primed or not. According to an embodiment, the metal substrate is unprimed, such that the coating composition is applied directly to the metal. According to another embodiment, the metal substrate is primed, such that the coating composition is applied to the primer.

[0101] Methods:

[0102] A method of applying a coating to a metal surface is provided. The method comprises: applying a coating comprising the aqueous polymer emulsion disclosed herein directly or indirectly to the metal surface; allowing the coating to dry to provide a dried coating.

[0103] According to some embodiments, the dried coating may have one or more of the following properties:

[0104] Konig hardness of 9 seconds or more as measured according to ASTM 4366-16; passes humidity testing according to ASTM D714-02; and / or no blistering under corrosion resistance testing according to ASTM Bl 17-19.

[0105] According to an embodiment, the substrate comprising a metal has a primer and the coating is applied to the primer. According to an embodiment, the method comprises providing a metal having one or more surfaces coated with a primer to provide at least one primed surface, and applying the coating to the at least one primed surface.

[0106] According to an embodiment, the coating is applied directly to the one or more surfaces of the metal. According to an embodiment, the coating is applied directly to the metal. Nonlimiting examples of metals are iron, brass, zinc, copper, tin, cold rolled steel, hot rolled steel, galvanized steel, aluminum, or combinations thereof. The metal substrate may be treated or untreated, and may be primed or not.

[0107] Non-limiting aspects of the invention are summarized as follows.

[0108] Aspect 1. An aqueous polymer emulsion, comprising polymer and water, the polymer comprising, as polymerized monomers: a) 20-70%, by weight of the polymer, of at least one ethylenically unsaturated monomer of structure (I) where R1is hydrogen or a methyl group and R2is a C6-C8 non-cyclic alkyl group, wherein the structure I has at least 63% biocarbon content as determined by ASTM 6866-22 Method B; b) 30-80%, by weight of the polymer, of an aryl-containing ethylenically unsaturated monomer, a C2-C6 ethylenically unsaturated monomer, or a combination thereof; c) 0.1 to 1.9 %, by weight of the polymer, of at least one phosphorus-containing free- radical polymerizable monomer, different from monomer a) and monomer b); d) 0 to 10 %, by weight of the polymer, of a free radical polymerizable monomer, different from monomer a), monomer b), and monomer c), comprising a beta dicarbonyl functionality; e) 0 to 1 .9 %, by weight of the polymer, of a free radical polymerizable polyethylenically unsaturated monomer different from a), b), c), and d); wherein the polymer has a minimum film forming temperature of less than 30°C as determined by ASTM D2354-10.

[0109] Aspect 2. The aqueous polymer emulsion of Aspect 1, wherein the polymer comprises at least 22% biocarbon content as determined by ASTM 6866-22 Method B.

[0110] Aspect 3. The aqueous polymer emulsion of Aspect 1 or Aspect 2, wherein the monomer c) comprises at least one of phosphoalkyl (meth)acrylates; phosphoalkyl (meth)acrylamides; phosphoalkyl crotonates, phosphoalkyl maleates, phosphoalkyl fumarates, phosphodialkyl (meth)acrylates, phosphodialkyl crotonates, vinyl phosphates or (meth)allyl phosphate; phosphate esters of polypropylene glycol mono(meth)acrylate or polyethylene glycol mono(meth)acrylate; polyoxyethylene allyl ether phosphate, vinyl phosphonic acid, or combinations thereof; preferably phosphoalkyl (meth)acrylates; polypropylene glycol mono(meth)acrylate or polyethylene glycol mono(meth)acrylate, or combinations thereof; more preferably phosphoalkyl (meth)acrylates, or combinations thereof.

[0111] Aspect 4. The aqueous polymer emulsion of any of Aspects 1-3 wherein the monomer a) comprises 2-hexyl (meth)acrylate, n-heptyl(meth)acrylate, 2-octyl acrylate, 2-octyl methacrylate, or combinations thereof; most preferably 2-octyl acrylate.

[0112] Aspect 5. The aqueous polymer emulsion of any of Aspects 1-4, wherein the monomer b) comprises at least one ethylenically unsaturated aromatic monomer, at least one C1-C5 (meth)acrylate, or a combination thereof; preferably styrene or a derivative thereof, C1-C2 (meth)acrylate, or a combination thereof; more preferably styrene and methyl methacrylate; most preferably styrene.

[0113] Aspect 6. The aqueous polymer emulsion of any of Aspects 1-5, comprising from 0.1 to 10%, preferably from 0.5 to 8%, more preferably from 1 to 6wt% of monomer d), by weight of the polymer.

[0114] Aspect 7. The aqueous polymer emulsion of Aspect 6, wherein monomer d) comprises at least one 1,3 -dicarbonyl group, preferably comprising diacetone acrylamide, acetoacetoxyethyl methacrylate (AAEM), or combinations thereof; more preferably acetoacetoxyethyl methacrylate.

[0115] Aspect 8. The aqueous polymer emulsion of any of Aspects 1-7, comprising from 0 to 1.9% of monomer e), or from 0 to 1.5% or monomer e), or from 0 to lwt% of monomer e), or from 0.01 to 1.9% of monomer e) or from 0.05 to 1.5 % of monomer e), or from 0.1 to 1 wt% of monomer e), by weight of the polymer.

[0116] Aspect 9. The aqueous polymer emulsion of Aspect 8, wherein the monomer e) comprises two or three unsaturated carbon-carbon double bonds capable of being free- radical polymerized, or a combination thereof; preferably 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 dimethacrylate, diethylene glycol dimethacrylate, trimethylolpropane tri(meth)acrylate, 1,3-butyleneglycol dimethacrylate, 1 ,4-butyleneglycol dimethacrylate, dipentaerythritol pentaacrylate, pentaerythritol tetraacrylate, 1,10-decanediol diacrylate, ethoxylated (2) bisphenol A diacrylate, 1,3 -propanediol dimethacrylate, 1,4- butanediol diacrylate, 1 ,4-butanediol dimethacrylate, 1,6-hexanediol diacrylate, 1,6 hexanediol dimethacrylate, dially phthalate, allyl methacrylate, divinylbenzene, or a combination thereof, more preferably divinylbenzene, 1 ,6-hexanediol diacrylate, allyl methacrylate, or a combination thereof.

[0117] Aspect 10. The aqueous polymer emulsion of any of Aspects 1-9, wherein the polymer is a single stage or multistage polymer.

[0118] Aspect 11. The aqueous polymer emulsion of any of Aspects 1-10, wherein the polymer has a single Tg as measured by differential scanning calorimetry (DSC).

[0119] Aspect 12. A coating comprising the aqueous polymer emulsion of any of Aspects 1-11 in dried form, wherein the coating has one or more, preferably at least two and most preferably each of the following properties:

[0120] Konig hardness of 9 seconds or more as measured according to ASTM 4366-16; passes humidity testing according to ASTM D714-02; and / or no blistering under corrosion resistance testing according to ASTM Bl 17-19.

[0121] Aspect 13. A coated substrate comprising the coating of Aspect 12, wherein the substrate comprises a metal.

[0122] Aspect 14. A method of applying a coating to a substrate comprising a metal surface, the method comprising: applying a coating comprising the aqueous polymer emulsion of any of Aspects 1-11 directly or indirectly to the metal surface; allowing the coating to dry to provide a dried coating.

[0123] Aspect 15. The method of Aspect 14, wherein the dried coating has one or more of the following properties:

[0124] Konig hardness of 9 seconds or more as measured according to ASTM 4366-16; passes humidity testing according to ASTM D714-02; and / or no blistering under corrosion resistance testing according to ASTM Bl 17-19.

[0125] Aspect 16. The method of Aspect 14 or Aspect 15, comprising providing a substrate having one or more surfaces coated with a primer to provide at least one primed surface, and applying the coating to the one or more primed surface.

[0126] Aspect 17. The method of Aspect 14 or Aspect 15, wherein the coating is applied directly to the one or more surfaces of the metal.

[0127] EXAMPLES

[0128] Methods:

[0129] Differential Scanning Calorimetry (DSC):

[0130] Glass transition temperature is measured using differential scanning calorimetry (TA Instrument Q2000) at a rate of 10°C / min. The half-height inflection point on the third heat cycle is reported as midpoint glass transition temperature. Polymer film water absorption:

[0131] The neat polymer emulsion was drawn down using a 20 mil draw down bar on a Leneta black scrub test panel (cut to 11.25 inch x 4 inch), allowing about 4 grams of resin to deposit on the panel. The fdms were dried for 3 days at controlled conditions of 73.5±3.5°F and relative humidity of 50±5%. The film was soaked in water for 96 hours, followed by removing surface water using paper towels. The mass difference between wet panels and dry panels was determined as water uptake.

[0132] Adhesion: Scale of 0-5 wherein 5 is best.

[0133] The adhesion of the coating compositions was tested according to ASTM D-3359-17, method B (crosshatch adhesion). The coating compositions were applied with a film applicator to the unprimed substrate panels with a wet coating thickness of about 3.5 mils (90 microns), resulting in a dry film thickness (DFT)g of 1.5 mil (38 microns) + / - 0.1 mil (2.5 microns). The films were dried in a climate-controlled room (50% Relative Humidity and 23° C.) for 1 and 7 days before testing adhesion. The films were scribed with a sharp razor knife in a 5 square x 5 square grid, being sure to cut through to the substrate. The dry adhesion was tested with the ASTM-specified tape, removing the tape in the manner described in the ASTM. Wet adhesion was conducted by soaking the crosshatch area with a wet paper towel for 20 minutes, blotted dry, and then allowed to recover for 30 minutes. After this time the film was tested in the same manner as the dry adhesion test. The adhesion was then visually rated on a scale of 0 to 5, with a 0 rating being complete film removal and 5 being 100% film adhesion. Accordingly, 5 is the best adhesion, and an adhesion rating of 4 is acceptable.

[0134] Konig Hardness:

[0135] Konig pendulum hardness of coating films was measured following ASTM 4366-16. The paint films were prepared on 3 inches by 12 inches (7.6 cm by 30.5 cm) glass plates using a 10- mil (254 pm) drawdown bar and allowed to dry for 7 days. The dry film thickness was approximately 4 mils (100 pm). The Konig pendulum resting on the coating surface was set into oscillation (rocking) and the time in seconds for the swing amplitude of the pendulum to decrease from 6 inches (15.2 cm) to 3 inches (7.6 cm) was recorded. The Konig hardness is measured in seconds. The results can be in the range of 0-150 second, and higher number means higher hardness, which is desirable. A Konig hardness for low VOC applications may be in the range of 8-30 seconds.

[0136] Humidity Resistance:

[0137] Films were cast onto treated aluminum panels with a 7-mil (18 pm) gap square applicator blade, resulting in a 3.5 mil (9 pm) wet film and a final Dry Film Thickness (DFT) of 1.5 mil (38 microns) + / - 0.1 mil (2.54 pm). The films were allowed to cure for 7 days and then placed in an enclosed chamber containing a heated, saturated mixture of air and water vapor. The temperature of the chamber is maintained at 122° F (50° C). After 72-hour exposure, the panels were visually evaluated for blistering (ASTM D 714).

[0138] Corrosion Resistance (Salt fog cabinet Test):

[0139] Salt fog cabinet test was conducted in accordance with ASTM B 117. Films were cast onto unprimed cold-rolled steel panels with a 7-mil (18 pm) gap square applicator blade, resulting in a 3.5 mil (9 pm) wet film and a final Dry Film Thickness (DFT) of 1.5 mil (38 microns) + / - 0.1 mil (2.54 microns). The films were cured for 7 days, scribed with a sharp razor knife and placed in a Q-Fog corrosion tester set for ASTM Bl 17 (2017) testing. The panels are evaluated by visual examination at regular intervals.

[0140] Electrochemical Impedance Spectroscopy (E.I.S.)

[0141] Electrochemical Impedance Spectroscopy (E.I.S.) testing includes the use of a small amplitude, alternating current signal to test the impedance properties of a film. A film was cast onto a cold-rolled steel panel by a 7-mil gap applicator bar and then allowed to cure for seven days. The films were then analyzed on a Gamry EIS300, which uses a wide range of frequencies to generate an impedance spectrum for the cell created with the pint film.

[0142] Inventive sample A preparation:

[0143] 375 parts of deionized water, 1.4 parts of anionic surfactant and 0.4 parts of ammonium hydroxide (28%) were charged into a reactor equipped with two 45-degree pitch blade turbines, reflux condensers, thermocouples, and stainless steel feed lines. The reactor was preheated to 85 °C. The monomer mixture including 365 parts water, 5.0 parts anionic surfactant, 16.24 parts phosphate containing monomer, 366.47 parts styrene, 484.45 parts 2-octyl acrylate, 36.14 parts methyl methacrylate was pre-emulsified by stirring in a separate container. 10 % of the monomer mixture was transferred to the reactor, followed by 2.2 parts ammonium persulfate pre -dissolved in 15 parts DI (deionized) water. The rest of the monomer mixture and the third stream (6.0 parts ammonium hydroxide (28%) dissolved in 30 parts DI water) was then added continuously to the reactor in 240 min. The delayed oxidizer (1.5 part ammonium persulfate dissolved in 32 parts DI water) was fed continuously into the reactor over 240 minutes. To reduce the residual monomer concentration, 2.6 parts of tertiary-butyl hydroperoxide (tBHP, dissolved in 11.05 parts DI water) and 2.28 parts of Bruggolite® FF6M (sodium salt of an organic sulfinic acid derivative dissolved in 22.50 parts of DI Water) were fed over 30 minutes at 70 °C. The solids content of the latex was 50% and particle size was about 120 nm. The measured copolymer Tg was 8 °C.

[0144] Comparative sample B preparation:

[0145] 460 parts of deionized water, 1.4 parts of anionic surfactant and 0.4 parts of ammonium hydroxide (28%) were charged into a reactor equipped with two 45-degree pitch blade turbines, reflux condensers, thermocouples, and stainless steel feed lines. The reactor was preheated to 85 °C. The monomer mixture including 365 parts water, 5.4 parts anionic surfactant, 16.24 parts phosphate containing monomer, 372.8 parts styrene, 478.13 parts butyl acrylate, 36.14 parts methyl methacrylate was pre-emulsified by stirring in a separate container. 10 % of the monomer mixture was transferred to the reactor, followed by 2.2 parts ammonium persulfate pre -dissolved in 15 parts DI Water. The rest of the monomer mixture and the third stream (6.0 parts ammonium hydroxide (28%) dissolved in 30 parts DI Water) was then added continuously to the reactor over 240 min. The delayed oxidizer (1.5 part ammonium persulfate dissolved in 32 parts DI water) was fed continuously into the reactor in 240 min. To reduce the residual monomer concentration, 2.6 parts of tertiary-butyl hydroperoxide (tBHP, dissolved in 11.05 parts DI water) and 2.28 parts of Bruggolite® FF6M (dissolved in 22.50 parts of DI Water) were fed over 30 minutes at 70 °C. The solids content of the latex was 48% and particle size was about 120 nm. The measured copolymer Tg was 5 °C.

[0146] Comparative sample C preparation:

[0147] 460 parts of deionized water, 1.4 parts of anionic surfactant and 0.4 parts of ammonium hydroxide (28%) were charged into a reactor equipped with two 45-degree pitch blade turbines, reflux condensers, thermocouples, and stainless steel feed lines. The reactor was preheated to 85 °C. The monomer mixture including 365 parts water, 5.4 parts anionic surfactant, 16.24 parts phosphate containing monomer, 237.07 parts styrene, 613.46 parts ethyl acrylate, 36.14 parts methyl methacrylate was pre-emulsified by stirring in a separate container. 10 % of the monomer mixture was transferred to the reactor, followed by 2.2 parts ammonium persulfate pre -dissolved in 15 parts DI water. The rest of the monomer mixture and the third stream (6.0 parts ammonium hydroxide (28%) dissolved in 30 parts DI Water) was then added continuously to the reactor over 240 min. The delayed oxidizer (1.5 part ammonium persulfate dissolved in 32 parts DI water) was fed continuously into the reactor over 240 min. To reduce the residual monomer concentration, 2.6 parts of tertiary-butyl hydroperoxide (tBHP, dissolved in 11.05 parts DI water) and 2.28 parts of Bruggolite® FF6M (dissolved in 22.50 parts of DI water) were fed over 30 minutes at 70 °C. The solids content of the latex was 50% and particle size was about 127 nm. The measured copolymer Tg was 4 °C.

[0148] The compositions of the Inventive sample A and Comparative samples B and C polymers are shown in Table 1. Table 1: Compositions of Inventive sample A and Comparative samples B and C polymers in weight percent monomer by total weight of each polymer.

[0149] *biobased

[0150] The clear film water absorption results are shown in Figure 1. Inventive sample A (based on biobased monomer 2-octyl acrylate) have much lower water absorption (<20%) after 96 hours soak, while comparative sample B (based on butyl acrylate) and comparative sample C (based on ethyl acrylate) have much higher water absorption (>30%) after 96-hour soak.

[0151] Performance testing in an example coating composition:

[0152] Samples A to C were formulated into white paint following the formulation shown in Table 2. The VOC content of all of the coating compositions was 50 g / L.

[0153] Table 2: Gloss white coating formulation.

[0154] The Gloss, Konig hardness and adhesion to certain substrates after 1 day and after 7 days of cure are shown in Table 3. A commercial non biobased 50 g / L VOC coating bought from a local store was included for performance comparison. All samples have acceptable gloss, Konig hardness and adhesion on different substrate as compared to the commercially available non biobased paint.

[0155] Table 3: Gloss, hardness and adhesion comparison The EIS comparison was shown in Figure 2. Comparative sample C (based on ethyl acrylate) has much lower resistance than other samples, indicating the film is too hydrophilic, and not suitable for industrial application.

[0156] These films were then put into 50°C humidity chamber for 72 hours, and the film appearance were visually checked for blistering. The ratings are summarized in Table 4. Inventive sample A (based on 2-OA monomer) shows no blistering after 72-hour exposure, while comparative sample B (based on butyl acrylate monomer) and comparative sample C (based on ethyl acrylate monomer) all showed blistering due to the relative hydrophilicity of the monomer. Therefore, comparative samples B and C are not suitable for industrial applications. Table 4: Paint film blister rating after 72-hour humidity exposure.

[0157] Figure 3 shows the 216-hour salt corrosion resistance properties of inventive sample A, comparative sample B, comparative sample C and a commercial sample. Clearly, inventive sample A has similar or slightly better corrosion resistance as compared to the non-biobased commercial sample as shown in Table 5.

[0158] Table 5: BCC measurement

[0159] Comparative Examples D-G Binders

[0160] Comparative Examples D-G, were prepared the same way as Examples A-C, above. The monomer compositions for these examples are shown in Table 5. Coating compositions were made from these binder samples D-G as shown in Table 5, using the same coating composition as shown in Table 2.

[0161] Table 5: Binders D-G composition

[0162] *bio-based ** Acetoacetoxyethyl methacrylate Figure 5 shows 200-hour salt corrosion resistance properties of coatings made with the comparative samples D-G binders. The comparative samples demonstrate that acrylic acid and methacrylic acid deteriorate the corrosion resistance of the paints.

[0163] 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.

[0164] 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. An aqueous polymer emulsion, comprising polymer and water, the polymer comprising, as polymerized monomers: a) 20-70%, by weight of the polymer, of at least one ethylenically unsaturated monomer of structure (I)where R1is hydrogen or a methyl group and R2is a C6-C8 non-cyclic alkyl group, wherein the structure I has at least 63% biocarbon content as determined by ASTM 6866-22 Method B; b) 30-80%, by weight of the polymer, of an aryl-containing ethylenically unsaturated monomer, a C2-C6 ethylenically unsaturated monomer, or a combination thereof; c) 0.1 to 1.9 %, by weight of the polymer, of at least one phosphorus-containing free-radical polymerizable monomer, different from monomer a) and monomer b); d) 0 to 10 %, by weight of the polymer, of a free radical polymerizable monomer, different from monomer a), monomer b), and monomer c), comprising a beta dicarbonyl functionality; e) 0 to 1.9 %, by weight of the polymer, of a free radical polymerizable polyethylenically unsaturated monomer different from a), b), c), and d); wherein the polymer has a minimum film forming temperature of less than 30°C as determined by ASTM D2354-10.

2. The aqueous polymer emulsion of claim 1, wherein the polymer comprises at least 22% biocarbon content as determined by ASTM 6866-22 Method B.

3. The aqueous polymer emulsion of claim 1 or claim 2, wherein the monomer c) comprises at least one of phosphoalkyl (meth)acrylates; phosphoalkyl (meth)acrylamides; phosphoalkyl crotonates, phosphoalkyl maleates, phosphoalkyl fumarates, phosphodialkyl (meth)acrylates, phosphodialkyl crotonates, vinyl phosphates or (meth)allyl phosphate; phosphate esters of polypropylene glycol mono(meth)acrylate or polyethylene glycol mono(meth)acrylate; polyoxyethylene allyl ether phosphate, vinyl phosphonic acid, or combinations thereof; preferably phosphoalkyl (meth)acrylates; polypropylene glycol mono(meth)acrylate or polyethylene glycol mono(meth)acrylate, or combinations thereof; more preferably phosphoalkyl (meth)acrylates, or combinations thereof.

4. The aqueous polymer emulsion of any of claims 1-3 wherein the monomer a) comprises 2- hexyl (meth)acrylate, n-heptyl(meth)acrylate, 2-octyl acrylate, 2-octyl methacrylate, or combinations thereof; most preferably 2-octyl acrylate.

5. The aqueous polymer emulsion of any of claims 1-4, wherein the monomer b) comprises at least one ethylenically unsaturated aromatic monomer, at least one C1-C5 (meth)acrylate, or a combination thereof; preferably styrene or a derivative thereof, C1-C2 (meth)acrylate, or a combination thereof; more preferably styrene and methyl methacrylate; most preferably styrene.

6. The aqueous polymer emulsion of any of claims 1-5, comprising from 0.1 to 10%, preferably from 0.5 to 8%, more preferably from 1 to 6wt% of monomer d), by weight of the polymer.

7. The aqueous polymer emulsion of claim 6, wherein monomer d) comprises at least one 1,3- dicarbonyl group, preferably comprising diacetone acrylamide, aceto acetoxy ethyl methacrylate (AAEM), or combinations thereof; more preferably aceto acetoxy ethyl methacrylate.

8. The aqueous polymer emulsion of any of claims 1-7, comprising from 0 to 1 .9% of monomer e), or from 0 to 1.5% or monomer e), or from 0 to lwt% of monomer e), or from 0.01 to 1.9% of monomer e) or from 0.05 to 1.5 % of monomer e), or from 0.1 to 1 wt% of monomer e), by weight of the polymer.

9. The aqueous polymer emulsion of claim 8, wherein the monomer e) comprises two or three unsaturated carbon-carbon double bonds capable of being free- radical polymerized, or a combination thereof; preferably 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 dimethacrylate, diethylene glycol dimethacrylate, trimethylolpropane tri(meth)acrylate, 1,3-butyleneglycol dimethacrylate, 1 ,4-butyleneglycol dimethacrylate, dipentaerythritol pentaacrylate, pentaerythritol tetraacrylate, 1,10-decanediol diacrylate, ethoxylated (2) bisphenol A diacrylate, 1,3 -propanediol dimethacrylate, 1,4- butanediol diacrylate, 1 ,4-butanediol dimethacrylate, 1 ,6-hexanediol diacrylate, 1,6 hexanediol dimethacrylate, dially phthalate, allyl methacrylate, divinylbenzene, or a combination thereof, more preferably divinylbenzene, 1 ,6-hexanediol diacrylate, allyl methacrylate, or a combination thereof.

10. The aqueous polymer emulsion of any of claims 1-9, wherein the polymer is a single stage or multistage polymer.

11. The aqueous polymer emulsion of any of claims 1-10, wherein the polymer has a single Tg as measured by differential scanning calorimetry (DSC).

12. A coating comprising the aqueous polymer emulsion of any of claims 1-11 in dried form, wherein the coating has one or more, preferably at least two and most preferably each of the following properties:Konig hardness of 9 seconds or more as measured according to ASTM 4366-16; passes humidity testing according to ASTM D714-02; and / or no blistering under corrosion resistance testing according to ASTM Bl 17-19.

13. A coated substrate comprising the coating of claim 12, wherein the substrate comprises a metal.

14. A method of applying a coating to a substrate comprising a metal surface, the method comprising: applying a coating comprising the aqueous polymer emulsion of any of claims 1-11 directly or indirectly to the metal surface; allowing the coating to dry to provide a dried coating.

15. The method of claim 14, wherein the dried coating has one or more of the following properties:Konig hardness of 9 seconds or more as measured according to ASTM 4366-16; passes humidity testing according to ASTM D714-02; and / or no blistering under corrosion resistance testing according to ASTM Bl 17-19.

16. The method of claim 14 or claim 15, comprising providing a substrate having one or more surfaces coated with a primer to provide at least one primed surface, and applying the coating to the one or more primed surface.

17. The method of claim 14 or claim 15, wherein the coating is applied directly to the one or more surfaces of the metal.

Images