Acrylic emulsions with intrinsic matte properties

Abstract

Disclosed herein are acrylic emulsion compositions having intrinsic matte properties and methods of synthesizing and using these emulsion compositions.

Description

Technical Field

[0001] The present disclosure relates generally to acrylic emulsions, and more particularly to acrylic emulsions having inherent matte properties, and methods of synthesizing and using these emulsion compositions. Background Art

[0002] Water-based coatings, such as latex or emulsion polymer coatings, constitute an important part of all coatings used today. Water-based coatings present advantages over conventional oil-based coatings because they contain less undesirable volatile organic solvents and are therefore more environmentally friendly. These polymer products are dispersed in aqueous media and are stable under such conditions, but can form a continuous dry film after removing the water. Many polymer coatings, once cured, are glossy, which may be desirable on various substrates (including floor tiles, wood, metals and fabrics). On the other hand, matte coating films based on polymer dispersions typically have low gloss, usually at a level of 30 or less according to a 60° Gardner Gloss scale measurement. The gloss of polymer-based films is directly related to micron-scale surface roughness. Summary of the invention

[0003] Disclosed herein are aqueous dispersions of acrylic polymers comprising particles of acrylic polymers dispersed in an aqueous medium, wherein the acrylic emulsion can inherently diffuse incident light to provide a matte effect. The matte effect is achieved without the use of organic or inorganic matting agents and provides an aesthetically pleasing natural appearance to the coating. In another aspect, provided herein are methods for making aqueous dispersions of acrylic polymers described herein. In some embodiments, the aqueous polymer dispersion is prepared using a free radical emulsion polymerization method. In some embodiments, the free radical emulsion polymerization method is performed in a dual feed reactor. BRIEF DESCRIPTION OF THE DRAWINGS

[0004] The accompanying drawings, which are incorporated in and constitute a part of this specification, illustrate several embodiments of the present disclosure and, together with the description, serve to explain the principles of the present disclosure.

[0005] Figure 1 A schematic diagram of a dual-feed polymerization reactor used in the synthesis of the acrylic emulsions of the present disclosure is provided.

[0006] Figure 2 A film-forming stage of the water-based emulsion of the present disclosure is provided. DETAILED DESCRIPTION

[0007] As used herein, the terms "comprising" and variations thereof are used synonymously with the terms "including" and variations thereof, and are open-ended, non-limiting terms. Although the terms "comprising" and "including" are used herein to describe various embodiments, the terms "consisting essentially of" and "consisting of" may be used in place of "comprising" and "including" to provide more specific embodiments, and these terms are also disclosed. As used in this disclosure and the appended claims, the singular forms "a / an", "the" include plural referents unless the context clearly dictates otherwise. Disclosure of percentage ranges and other ranges herein includes disclosure of the endpoints of the range and any integers provided within the range.

[0008] I. Acrylic emulsion with inherent matte properties

[0009] The present disclosure provides acrylic emulsions with inherent matte properties, and methods for synthesizing the same. The acrylic emulsions can be prepared by free radical emulsion polymerization in a dual feed reactor. The resulting emulsion polymer exhibits an aesthetically natural appearance without the use of organic or inorganic matting agents. Due to the absence of matting agents, the films of the present disclosure are advantageous for reasons of chemical resistance, scratch resistance, mar resistance, dry film clarity, haze level, shelf life, and viscosity.

[0010] Common matting agents include silica, polyurea, polyacrylate, polyethylene, polytetrafluoroethylene, organic wax, aluminum stearate, calcium stearate, polymethyl methacrylate, and mixtures thereof. These matting agents are undesirable in polymer films because they may increase the complexity of the formulation through changes in viscosity and pH. In addition, excessive use of matting agents may affect the stability of the coating during the shelf life of the entire product or cause gelation in the film if too much filler is added. Ultra-low matte films often require a variety of particle sizes for the matting agent. In particular, the use of inorganic silica leads to excessive crystalline dust during production, which is a significant safety hazard.

[0011] Typical formulations of the emulsions disclosed herein may include copolymers, chain transfer agents, and surfactants. Other ingredients may be added to harden or soften the product. Colorants may also be added. Defoamers may be added.

[0012] The acrylic emulsion of the present invention can be acrylic or styrene-acrylic copolymer. Suitable monomers used in the preparation of the emulsion include, but are not limited to, acrylic acid in an amount of about 0%-2.0% by weight, methacrylic acid in an amount of about 0%-2.0% by weight, styrene in an amount of about 0%-55% by weight, hydroxyethyl methacrylate in an amount of about 0%-5% by weight, butyl acrylate in an amount of about 0%-48% by weight, butyl methacrylate in an amount of about 0%-25% by weight, and styrene in an amount of about 0%-55% by weight, based on the total weight of the composition. %-5% by weight of methyl methacrylate, diacetone acrylamide in an amount of about 0%-5% by weight, methacrylate in an amount of about 0%-15% by weight, ethyl acrylate in an amount of about 0%-15% by weight, glycidyl methacrylate in an amount of about 0%-5% by weight, 2-ethylhexyl acrylate in an amount of about 0%-40% by weight, isobutyl acrylate in an amount of about 0%-10% by weight, and isobutyl methacrylate in an amount of about 0%-10% by weight.

[0013] In certain embodiments, copolymer can be carboxylic acid functional resin.In certain embodiments, carboxylic acid functional resin can be alkali soluble resin.In other words, carboxylic acid functional resin can react with alkaline material to form ionic salt at the carboxylate group of polymer, thereby enhancing the water solubility characteristics of resin.Suitable monomer for preparing carboxylic acid functional resin and low molecular weight copolymer includes monomers such as acrylic acid, methacrylic acid, itaconic acid, maleic acid, fumaric acid, crotonic acid, acrylic anhydride, methacrylic anhydride, itaconic anhydride, maleic anhydride, fumaric anhydride, crotonic anhydride, styrene, methyl styrene, α-methyl styrene, ethyl styrene, isopropyl styrene, tert-butyl styrene, ethyl methacrylate, methyl methacrylate, butyl acrylate, butyl methacrylate, 2-ethylhexyl acrylate, ethyl acrylate, vinyl acetate, methyl acrylate, open chain conjugated diene, 2-hydroxyethyl methacrylate, 2-hydroxyethyl acrylate, hydroxymethyl acrylamide, glycidyl acrylate, glycidyl methacrylate, vinyl ester, vinyl chloride, or any two or more mixtures of such monomers. In some embodiments, the carboxylic acid functional carrier resin includes one or more of the following polymerized monomers: ethyl methacrylate, methyl methacrylate, butyl acrylate, butyl methacrylate, 2-ethylhexyl acrylate, ethyl acrylate, vinyl acetate, methyl acrylate, 2-hydroxyethyl methacrylate, 2-hydroxyethyl acrylate, glycidyl acrylate, glycidyl methacrylate, or any mixture of two or more such monomers. In one embodiment, the carboxylic acid functional resin includes one or more of the following polymerized monomers: acrylic acid, ethyl methacrylate, methyl methacrylate, butyl acrylate, butyl methacrylate, 2-ethylhexyl acrylate, ethyl acrylate, vinyl acetate, methyl acrylate, 2-hydroxyethyl methacrylate, 2-hydroxyethyl acrylate, glycidyl acrylate, glycidyl methacrylate, styrene, methyl styrene, α-methyl styrene, diacetone acrylamide, urea methacrylate, or any mixture of two or more such monomers. In some embodiments, the carboxylic acid functional resin may include a copolymer comprising two or more of styrene, methyl methacrylate, and acrylic acid. In some embodiments, the carboxylic acid functional carrier resin may include a copolymer of acrylic acid and styrene.

[0014] The one or more polymers used in the emulsion may have a glass transition temperature (Tg) of -60°C to 130°C for the individual polymers, or any sub-range or value within the range. For example, any given polymer in the emulsion may have a glass transition temperature (Tg) of -60°C to 100°C, -60°C to 75°C, -60°C to 50°C, -15°C to 50°C, -15°C to 45°C, -15°C to 40°C, -15°C to 35°C, -15°C to 30°C, -15°C to 25°C, -15°C to 20°C, -15°C to 15°C, -15°C to 10°C, -15°C to 5°C, -15°C to 5°C, -15°C to 5°C, -15°C to 60°C, -15°C to 75°C, -15°C to 80°C, -15°C to 90°C, -15°C to 100°C, -15°C to 15 ... 0°C, 0°C to 50°C, 0°C to 45°C, 0°C to 40°C, 0°C to 35°C, 0°C to 30°C, 0°C to 20°C, 0°C to 15°C, 0°C to 10°C, 10°C to 50°C, 10°C to 45°C, 10°C to 40°C, 10°C to 35°C, 10°C to 30°C, 10°C to 25°C, 10°C to 20°C, or any range of Tg including any two of these values ​​as endpoints.

[0015] The emulsion or combination of polymers can have a glass transition temperature (Tg) of -60°C to 130°C for the individual polymers, or any sub-range or value within the range. For example, any given polymer within the emulsion can have a glass transition temperature (Tg) of -60°C to 100°C, -60°C to 75°C, -60°C to 50°C, -15°C to 50°C, -15°C to 45°C, -15°C to 40°C, -15°C to 35°C, -15°C to 30°C, -15°C to 25°C, -15°C to 20°C, -15°C to 15°C, -15°C to 10°C, -15°C to 5°C, -15°C to 5°C, -15°C to 60°C, -15°C to 75°C, -15°C to 80°C, -15°C to 90°C, -15°C to 100°C, -15°C to 15 ... 0°C, 0°C to 50°C, 0°C to 45°C, 0°C to 40°C, 0°C to 35°C, 0°C to 30°C, 0°C to 20°C, 0°C to 15°C, 0°C to 10°C, 10°C to 50°C, 10°C to 45°C, 10°C to 40°C, 10°C to 35°C, 10°C to 30°C, 10°C to 25°C, 10°C to 20°C, or any range of Tg including any two of these values ​​as endpoints.

[0016] These polymers can be formed from emulsion polymerizable monomers. Emulsion polymerizable monomers are known in the art, see, for example, U.S. Patent Nos. 4,820,762; 7,253,218; 7,893,149; and U.S. Patent Publication No. 2015 / 0166803. Emulsion polymerizable monomers can include ethylenically unsaturated monomers. In some embodiments, emulsion polymerizable monomers can include at least one ethylenically unsaturated nonionic monomer. "Nonionic monomer" herein means that the comonomer residue does not carry an ionic charge between pH 1 and 14. Suitable ethylenically unsaturated nonionic monomers include, but are not limited to, (meth)acrylate monomers, including methyl acrylate, ethyl acrylate, butyl acrylate, 2-ethylhexyl acrylate, decyl acrylate, lauryl acrylate, methyl methacrylate, butyl methacrylate, isodecyl methacrylate, lauryl methacrylate, hydroxyethyl methacrylate, hydroxypropyl methacrylate; (meth)acrylonitrile; (meth)acrylamide; urea-functional monomers; monomers with acetoacetate functionality; styrene and substituted styrenes; butadiene; ethylene, propylene, α-olefins such as 1-decene; vinyl acetate, vinyl butyrate and other vinyl esters; and vinyl monomers such as vinyl chloride and vinylidene chloride.

[0017] The emulsion-polymerizable monomer may include an acrylate monomer, a methacrylate monomer, a styrene monomer, or a mixture of any two or more thereof. In some embodiments, the emulsion-polymerizable monomer does not include a styrene monomer.

[0018] In some embodiments, at least one emulsion polymerizable monomer may be a C1-C4 acrylate, a C1-C4 (meth)acrylate, or a mixture of any two or more thereof. In some embodiments, the emulsion polymerizable monomer may be n-butyl acrylate, 2-ethylhexyl acrylate, methyl acrylate, methyl methacrylate, styrene, ethyl acrylate, or a mixture of any two or more thereof.

[0019] In certain embodiments, the polymer of emulsion polymerizable can include one or more ketone functional monomers. Examples of ketone functional monomers include diacetone acrylamide, diacetone methacrylamide, diacetone acrylate, diacetone methacrylate, (methyl) acetoacetoxymethyl acrylate, (methyl) 2-(acetoacetoxy)ethyl acrylate, (methyl) 2-acetoacetoxypropyl acrylate, butanediol-1,4-acrylate-acetoacetate, vinyl methyl ketone, vinyl ethyl ketone, and vinyl isobutyl ketone, allyl acetoacetate, vinyl acetoacetate, or vinyl acetoacetamide. In one embodiment, the polymer of emulsion polymerizable includes repeating units derived from diacetone acrylamide.

[0020] The emulsion can be formed by an emulsion polymerization reaction, which can involve at least one emulsion polymerizable monomer, a low molecular weight copolymer, and other ingredients and / or reagents (such as an initiator). In some embodiments, the emulsion polymerization occurs in a dual feed reactor.

[0021] Initiator can be a water-soluble compound that is easy to mix and blend with emulsion. Non-limiting examples of water-soluble initiators for emulsion polymerization include ammonium salts and alkali metal salts of peroxodisulfuric acid, such as sodium peroxodisulfate, hydrogen peroxide or organic peroxides, such as tert-butyl hydroperoxide. Initiator can be a thermal initiator. Suitable initiators include but are not limited to 2,2'-azobis(2-methylpropionamidine) dihydrochloride, ammonium persulfate, sodium persulfate and potassium persulfate. Also suitable is a reduction-oxidation (redox) initiator system. The redox initiator system is composed of at least one generally inorganic reducing agent and an organic or inorganic oxidizing agent. The oxidizing component includes, for example, the emulsion polymerization initiator determined above. The reducing component includes, for example, an alkali metal salt of sulfurous acid, such as sodium sulfite, sodium bisulfite, an alkali metal salt of disulfurous acid such as sodium bisulfite, a bisulfite addition compound with aliphatic aldehydes and ketones such as acetone bisulfite, or a reducing agent such as hydroxymethanesulfinic acid and its salt, or ascorbic acid. Redox initiator systems can be used with soluble metal compounds, the metal components of which can exist in multiple valence states. Typical redox initiator systems are, for example, ascorbic acid / iron sulfate (II) / sodium peroxodisulfate, tert-butyl hydroperoxide / sodium disulfite, tert-butyl hydroperoxide / hydroxymethanesulfinic acid Na. These individual components (e.g., reducing components) can also be mixtures, an example being a mixture of the sodium salt of hydroxymethanesulfinic acid and sodium disulfite. The compound is usually used in the form of an aqueous solution, wherein the lower limit concentration is determined by the amount of acceptable water in the dispersion, and the upper limit concentration is determined by the solubility of the corresponding compound in water. In general, the concentration is 0.1% to 30% by weight based on the solution, preferably 0.5% to 20% by weight, more preferably 1.0% to 10% by weight. The amount of initiator is usually 0.1% to 10% by weight based on the monomer to be polymerized, preferably 0.5% to 5% by weight. It is also possible to use two or more different initiators in emulsion polymerization.

[0022] In some embodiments, the initiator can be ammonium persulfate and the oxidant can be tert-butyl hydroperoxide. In this case, the weight ratio between ammonium persulfate and tert-butyl hydroperoxide can range from 40:1 to 2:1 or 30:1 to 4:1 or any sub-range or value within these ranges.

[0023] In certain embodiments, the emulsion comprises one or more chain transfer agents to control molecular weight, branching and / or gel formation.Exemplary chain transfer agents include but are not limited to isooctyl mercaptopropionate (IOMPA), butyl mercaptopropionate, 2-ethylhexyl mercaptopropionate, tert-dodecyl mercaptan, and thioglycerol.

[0024] Generally, the amount of chain transfer agent employed may vary from 0.01 to 1% by weight, based on the total amount of monomers to be polymerized.

[0025] The polymer emulsions described herein may also contain surfactants. In some embodiments, the surfactant is anionic or nonionic. In some embodiments, the surfactant contains one or more fatty alcohol alkoxylates. In other embodiments, one or more fatty alcohol alkoxylates are fatty alcohol ethoxylates, fatty alcohol propoxylates, or any combination thereof. In some embodiments, the surfactant contains one or more ethylene oxide / propylene oxide block copolymers. In some embodiments, the surfactant contains one or more fatty alcohol ethoxylates. In some embodiments, the surfactant contains one or more alkyl sulfosuccinate ethoxylates. In some embodiments, the surfactant contains one or more fatty alcohols (having an alkyl chain length of about 12 to about 18 carbons; and a degree of ethoxylation of about 10 to about 80 moles of ethylene oxide units). In some embodiments, the surfactant includes a nonionic surfactant. In some embodiments, the surfactant includes an anionic surfactant. In some embodiments, the anionic surfactant includes one or more alkyl sulfonates, alkylbenzene sulfonates, alkyl sulfates, alkylbenzene sulfates, phosphates, phosphinates, fatty carboxylates, or any combination of two or more thereof.

[0026] Typically, the amount of surfactant employed may vary from 0.3 to 1% by weight, based on the total amount of monomers to be polymerized.

[0027] The polymer compositions described herein may contain other materials such as, but not limited to, other aqueous resin solutions, rheology modifiers, wetting agents, defoamers, thickeners, stabilizers, buffers, salts, preservatives, flame retardants, biocides, corrosion inhibitors, crosslinking agents, lubricants, colorants, dyes, waxes, fragrances, and fillers.

[0028] In some preferred embodiments, the polymer compositions described herein are substantially free of matting agents. "Substantially free of matting agents" as used herein indicates that the aqueous coating composition contains less than 0.1% by weight of matting agents based on the total weight of the aqueous coating composition. The term "matting agent" as used herein includes, but is not limited to, silica, polyurea, polyacrylate, polyethylene, polytetrafluoroethylene, organic wax, aluminum stearate, calcium stearate, polymethyl methacrylate, and mixtures thereof. The matting agent can be a powder or an emulsion.

[0029] In a particularly preferred embodiment, the polymer compositions described herein are completely free of matting agents.

[0030] As described herein, the acrylic or styrene-acrylic latex dispersion particles can have d(0.1) of 0.1 μm or greater, 0.5 μm or greater, or 1 μm or greater. Large and multimodal particle size distributions are aided by the lack of micelles caused by injecting monomer and seed polymer into the reactor during the initial stages of polymerization. Additionally, ramp-up and ramp-down power feeding of surfactant and monomer promotes large and multimodal particle sizes.

[0031] As described herein, the polymer film of the present disclosure can have a low gloss as measured by a gloss meter. At an angle of 20° on a black background, the film of the present invention can have a gloss of 20GU or less, 15GU or less, 10GU or less, or 5GU or less. At an angle of 20° on a white background, the film of the present invention can have a gloss of 20GU or less, 15GU or less, 10GU or less, or 5GU or less. At an angle of 60° on a black background, the film of the present invention can have a gloss of 30GU or less, 25GU or less, 20GU or less, or 15GU or less. At an angle of 60° on a white background, the film of the present invention can have a gloss of 30GU or less, 25GU or less, 20GU or less, or 15GU or less. At an angle of 85° on a black background, the film of the present invention can have a gloss of 60GU or less, 55GU or less, 50GU or less, or 45GU or less. The films of the present invention may have a gloss of 65 GU or less, 60 GU or less, 55 GU or less, or 50 GU or less as measured by the ASTM D523 test method for specular gloss at an angle of 85° on a white background.

[0032] II. Method for producing emulsion

[0033] The emulsions disclosed herein can be formed by emulsion polymerization, which relies on the use of small molecule surfactants containing polar / hydrophilic groups and non-polar / hydrophobic groups. The amphiphilic nature of these materials allows them to effectively stabilize heterogeneous solutions (i.e., polymer particles in water). The emulsion polymerization reactions disclosed herein can be carried out in dual feed reactors (e.g., Figure 1 The reactor can be equipped with a water bath, a mechanical stirrer, a temperature control probe, a feed tube for monomer addition, a feed tube for initiator addition, and a reflux condenser. Typically, each tank is filled with the following contents listed in Table 1.

[0034] Table 1. Figure 1 The charging of the different vessels in the dual-feed reactor is depicted in .

[0035]

[0036] Initially, DI water was charged to the reactor 14, which was then heated to 85°C. Acid monomer at 80°C was added to the reactor 14 in one shot, followed by the addition of an initial initiator shot from tank 10 pumped into the reactor 14 via pump 20. Then, a pre-emulsion feed containing DI water, surfactant, monomer A, and optionally a chain transfer agent in tank 12 was pumped by pump 18 to feed into the reactor 14. At the same time, a pure monomer feed containing monomer A in tank 16 was pumped into the reactor 14 by pump 22. After 15 minutes of pre-emulsion, a second charge of the initiator feed from tank 10 was pumped into the reactor 14. The total feed time was three hours. At the end of the pre-emulsion, the pure monomer feed and the initiator feed kept the reactor at 85°C for 30 minutes, and then rinse water was added to reduce the temperature to 70°C. After the chemical stripping process was completed, the reactor 14 was cooled to room temperature, and then the polymer finished polymer was filtered into a storage container.

[0037] As described herein, the free radical initiator can be a water-soluble initiator. Examples of such water-soluble initiators can include, but are not limited to, persulfates such as sodium persulfate (Na2S2O8), ammonium persulfate, and potassium persulfate; peroxides such as hydrogen peroxide and tert-butyl hydroperoxide (t-BHP); and azo compounds such as VAZO commercially available from Chemours Company. TM Initiators. They can be used alone or in combination with one or more reducing agents or activators (e.g., bisulfite, metabisulfite, ascorbic acid, isoascorbic acid, sodium formaldehyde sulfoxylate, ferrous sulfate, ammonium ferrous sulfate, and ethylenediaminetetraacetic acid iron).

[0038] Typically, the amount of free radical initiator employed may vary from 0.1 to 1% by weight, based on the total amount of monomers to be polymerized.

[0039] The following examples are intended to further illustrate certain aspects of the methods and compositions described herein and are not intended to limit the scope of the claims.

[0040] Examples

[0041] The following examples are presented to provide a person of ordinary skill in the art with a complete disclosure and description of how to make and evaluate the compositions and / or methods claimed herein, and are intended to be exemplary only and are not intended to limit the scope of the present disclosure. Unless otherwise indicated, parts are parts by weight, temperatures are in ° C. or at ambient temperature, and pressures are equal to or close to atmospheric pressure.

[0042] The particle size distribution percentiles are represented by the letter "d" followed by the % value. Thus, d(0.1) or d10 = 1.107 uM, d(0.5) or d(50) = 3.79 uM and d(0.9) or d(90) = 7.094 uM means that 10% of the sample is less than 1.107 uM, 50% of the sample is less than 3.79 uM and 90% of the sample is less than 7.094 uM.

[0043] Example 1: Synthesis of acrylic emulsion

[0044] Initially, the polymerization reactor was charged with the required amount of DI water, about 25% of the total surfactant amount, and seed polymer. The reactor was heated to 85°C, and 80°C of acid monomer was added at once. Then the initial initiator injection amount (about 25% of the total initiator solution) was added immediately at 85°C. After the initiator injection amount, the pre-emulsion feed and the pure monomer feed were started at the same time. After 15 minutes of pre-emulsion feed and pure monomer feed, the second charge of the initiator feed was started. The total feed (pure monomer+pre-emulsion+initiator) time was 3 hours. At the end of the pre-emulsion, the pure monomer and initiator feeds maintained the reactor at 85°C for 30 minutes, and then rinse water was added to reduce the reactor temperature to 70°C. At 70°C, delayed oxidant and reductant feeds were started to reduce residual monomers. After the chemical stripping process was completed, the reaction was cooled to room temperature. Finally, the post-addition solution was added, and the reactor mixed contents for 15 minutes, and then the polymer was filtered in a storage container.

[0045] Table 2. List of acrylic emulsion formulations.

[0046]

[0047] Table 3. Particle size distribution of formulations 1-14.

[0048]

[0049] Table 4. Gloss measurements of Formulations 1-14.

[0050]

Claims

1. A polymer emulsion composition comprising at least one block copolymer; At least one chain transfer agent At least one surfactant in, The polymer emulsion is substantially free of organic or inorganic matting agents.

2. The polymer emulsion composition according to claim 1, wherein The organic or inorganic matting agent includes silica, polyurea, polyacrylate, polyethylene, polytetrafluoroethylene, organic wax, aluminum stearate, calcium stearate, polymethyl methacrylate, and / or a mixture thereof.

3. The polymer emulsion composition according to claim 1, wherein The emulsion inherently diffuses incident light to provide a matte effect.

4. The polymer emulsion composition according to claim 1, wherein The particles of the acrylic polymer have a measured d(0.5) value of 1 μm or greater.

5. The polymer emulsion according to claim 1, wherein The emulsion composition has a glass transition temperature of -60°C to 130°C.

6. The polymer emulsion according to claim 1, wherein The copolymer is an acrylic or a styrene-acrylic copolymer.

7. The polymer emulsion composition according to claim 1, wherein The polymer contains the functional monomers acrylic acid, methacrylic acid, styrene, α-methylstyrene, hydroxyethyl methacrylate, esters of acrylic acid or methacrylic acid.

8. The polymer emulsion according to claim 1, wherein The chain transfer agent is present in an amount of 0.01 wt. % to 1 wt. % based on the total weight of the composition.

9. The polymer emulsion according to claim 1, wherein The chain transfer agent is selected from the group consisting of isooctyl mercaptopropionate (IOMPA), butyl mercaptopropionate, 2-ethylhexyl mercaptopropionate, tert-dodecyl mercaptan, and thioglycerol.

10. The polymer emulsion according to claim 1, wherein The surfactant is present in an amount of 0.3 wt. % to 1 wt. % based on the total weight of the composition.

11. The polymer emulsion according to claim 1, wherein The surfactant is selected from the group consisting of fatty alcohol alkoxylates, fatty alcohol ethoxylates, ethylene oxide block copolymers, propylene oxide block copolymers, alkyl sulfonates, alkyl benzene sulfonates, alkyl sulfates, alkyl benzene sulfates, phosphates, phosphinates, or fatty carboxylates.

12. The polymer emulsion according to claim 1, wherein The emulsion further comprises an aqueous resin solution, a rheology modifier, a wetting agent, a defoamer, a thickener, a stabilizer, a buffer, a salt, a preservative, a flame retardant, a biocide, a corrosion inhibitor, a crosslinking agent, a lubricant, a colorant, a dye, a wax, a fragrance, or a filler.

13. A method for producing the polymer emulsion according to claim 1 in a dual feed reactor, the method comprising (i) charging DI water, surfactant, and seed polymer into a polymerization reactor; (ii) adding an initiator to the reactor; (iii) feeding monomers from two separate tanks into the reactor to form a polymer composition; (iv) adding rinse water to the reactor; (v) chemically stripping the polymer composition; and (vi) filtering the polymer composition into a storage container.

14. The method of claim 13, wherein: The monomer feed was gradually increased and decreased.

15. The method of claim 13, wherein: The dual-power feed synthesis process produces gradient molecular weight polymer chains.

16. The method of claim 13, wherein: The dual power feed synthesis process produces a broad Tg of the resulting polymer dispersion.

17. The method of claim 13, wherein: The dual-power feed synthesis process produces a gradient Tg.

18. A substrate coated with the composition of claim 1.

19. The coated substrate of claim 18, wherein The substrate has a gloss value of 20 GU or less as measured by a gloss meter at an angle of 20° on a black background.

20. The coated substrate of claim 18, wherein The substrate has a gloss value of 30 GU or less as measured by a gloss meter at an angle of 60° on a black background.

21. The coated substrate of claim 18, wherein The substrate has a gloss value of 60 GU or less as measured by a gloss meter at an angle of 85° on a black background.

22. The coated substrate of claim 18, wherein The substrate has a gloss value of 20 GU or less as measured by a gloss meter at an angle of 20° on a white background.

23. The coated substrate of claim 18, wherein The substrate has a gloss value of 30 GU or less as measured by a gloss meter at an angle of 60° on a white background.

24. The coated substrate of claim 18, wherein The substrate has a gloss value of 65 GU or less as measured by a gloss meter at an angle of 85° on a white background.

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