Aqueous compositions with improved barrier properties

Abstract

The presently claimed invention relates to aqueous compositions for improving barrier properties. In particular, the presently claimed invention relates to polymer-based, grease-resistant aqueous compositions for coating paper and paper products.

Description

[Technical Field]

[0001] The presently claimed invention relates to aqueous compositions for improving barrier properties. In particular, the presently claimed invention relates to polymer-based grease-resistant coating compositions. [Background technology]

[0002] Sustainable packaging materials using renewable and recyclable materials are increasingly and strongly desired, especially in food service and food packaging. Paper or paperboard is one of the most sustainable materials for packaging applications and is typically coated with a composition that provides barrier properties to meet packaging requirements. Barrier properties are important in reducing the penetration of moisture, oil, grease, flavors, and in some cases, bacteria. Therefore, the paper industry continues to apply coating compositions and surface sizing techniques to paper or paperboard substrates to provide barrier properties and other desirable and beneficial attributes to the paper. Properties imparted to the paper by coating compositions include reduced porosity to air, water resistance, oil and grease resistance, improved surface strength, and improved quality and ease of printing on the paper.

[0003] Coating compositions widely used commercially to impart oil and grease resistance to paper contain fluorochemicals. While effective, such coating compositions are not environmentally friendly and pose various health and safety concerns due to toxicity. Another well-known type of coating that has been used conventionally is a composition with a plastic film, such as polyethylene or polypropylene, which provides barrier properties and flexibility for making folding paperboard. However, while these films provide good barrier properties and foldability, they limit the recyclability and pulpability of the coated paper product. Water-based coatings offer an environmentally friendly alternative to polyethylene coatings because they are recyclable and repulpable. However, water-based coatings known in the art are not suitable for folding paperboard because cracks formed at the fold lines reduce barrier properties.

[0004] For a coating to be effective, it must constitute a flexible film capable of resisting penetration by oil and / or grease. Furthermore, it is important that these properties remain intact after the paper or paperboard substrate is converted from a flat sheet into a label or packaging material. Blocking, or the tendency of layers in a roll of paperboard to stick to each other, is another hurdle in the manufacturing and converting process of coated paperboard. These are some of the obstacles in existing barrier coating compositions.

[0005] Therefore, there is a need for improved coating compositions that can overcome the above-mentioned drawbacks for use in producing oil- and grease-resistant paper that is safe for the environment and consumers, and that can impart properties such as blocking resistance and foldability to paper and paper substrates that can also be recycled and repulped at low cost. [Prior art documents] [Patent documents]

[0006] [Patent Document 1] U.S. Patent No. 5,461,60 [Patent Document 2] U.S. Patent No. 4,414,370 [Patent Document 3] U.S. Patent No. 4,529,787 [Non-patent literature]

[0007] [Non-Patent Document 1] M. Antonelli and K. Tauer, Macromol. Chem. Phys. 2003, vol. 204, pp. 207-19 [Non-patent document 2] AS Sarac, Progress in Polymer Science 24, 1149-1204 (1999) [Non-patent document 3] TAPPI T 441(2001) Summary of the Invention [Problem to be solved by the invention]

[0008] It is therefore an object of the presently claimed invention to provide an improved composition for oil and grease resistance of paper that is environmentally friendly and safe. Another object of the presently claimed invention is to provide an improved composition that can impart good barrier properties, blocking resistance, and folding properties to paper. [Means for solving the problem]

[0009] It has been surprisingly found that the aqueous compositions disclosed herein, comprising at least one first polymer and at least one second polymer, impart coating properties to paper or paper substrates, such as improved block resistance, grease resistance, foldability, etc. Furthermore, the compositions not only impart improved properties, but also enable the paper to be printable, recyclable, and repulpable, and are environmentally friendly.

[0010] Thus, in one aspect, the presently claimed invention comprises: (i) at least one first polymer in an amount ranging from about 10% to about 90% by weight derived from at least one first monomer selected from an ethylenically substituted aromatic compound and at least one second monomer selected from the group consisting of (meth)acrylonitrile, (meth)acrylamide, (meth)acrylic acid, alkyl (meth)acrylate, and mixtures thereof; and (ii) at least one second polymer in an amount ranging from about 10% to about 90% by weight, comprising the reaction product of a partially neutralized acid-functional support resin with at least one ethylenically unsaturated monomer selected from the group consisting of olefins, monovinylidene aromatic compounds, α,β-ethylenically unsaturated carboxylic acids and esters thereof, ethylenically unsaturated dicarboxylic acid anhydrides, and mixtures thereof; Including, All weight percentages refer to the aqueous composition and are based on the total weight of the aqueous composition.

[0011] In accordance with another aspect of the presently claimed invention, there is provided a substrate comprising at least one surface coated with at least one layer comprising the aqueous composition described herein.

[0012] According to another aspect of the presently claimed invention, there is provided a coated paper or article comprising the aqueous composition described herein.

[0013] According to another aspect of the presently claimed invention, there is provided a method of making paper comprising at least the step of contacting cellulose fibers with an aqueous composition described herein.

[0014] Other objects, advantages and uses of the invention claimed herein will become apparent to those skilled in the art from the following detailed description. DETAILED DESCRIPTION OF THE INVENTION

[0015] The claimed invention should not be limited to the embodiments described in this application. It will be apparent to those skilled in the art that modifications and variations can be made without departing from the spirit and scope of the present application. Functionally equivalent methods, compositions, and devices within the scope of the present disclosure, in addition to those enumerated herein, will be apparent to those skilled in the art from the foregoing description. These modifications and variations are intended to fall within the scope of the appended claims. The present disclosure is to be limited only by the terms of the appended claims, along with the full range of equivalents to which such claims are entitled. It is to be understood that the present disclosure is not limited to methodologies, reagents, compounds, or compositions, which may naturally vary. It is also to be understood that the terminology used herein is for the purpose of describing embodiments only, and is not intended to be limiting.

[0016] As used herein, the terms "comprising," "comprises," and "comprised of" are synonymous with "including," "includes," or "containing," and "contains," and are inclusive or open-ended and do not exclude additional, unrecited members, elements, or method steps. It will be recognized that the terms "comprising," "comprises," and "comprised of," as used herein, include the terms "consisting of," "consists," and "consists of."

[0017] Furthermore, the terms "(a)," "(b)," "(c)," "(d)," etc. in the specification and claims are used to distinguish between like elements and are not necessarily used to describe a chronological or chronological order. It is to be understood that the terms so used are interchangeable under appropriate circumstances, and that embodiments of the subject matter described herein are capable of operation in orders other than those described or illustrated herein. When the terms "(A)," "(B)," and "(C)" or "(a)," "(b)," "(c)," "(d)," "(i)," "(ii)," etc. refer to steps of a method or use or assay, there is no consistency of time or time interval between the steps; i.e., unless otherwise indicated in the application, as above or below, the steps may occur simultaneously or there may be time intervals of seconds, minutes, hours, days, weeks, months, or even years between the steps.

[0018] In the presently claimed invention, where features or aspects of the disclosure are described in terms of a Markush group, one of skill in the art will recognize that the disclosure is also described herein in terms of any individual member or subgroup of members of the Markush group.

[0019] For the purposes of the claimed invention, all ranges disclosed herein encompass all possible subranges and combinations of subranges. Ranges defined throughout this specification are inclusive, i.e., a range of 1 to 10 implies that both 1 and 10 are included within the range. For the avoidance of doubt, the applicant is entitled to any equivalents pursuant to applicable law. Any recited range can be readily recognized as fully descriptive and allowing for division of the range into at least two, three, four, five, ten, etc. As a non-limiting example, each range described herein can be readily divided into a lower third, middle third, upper third, etc. As one of ordinary skill in the art will also understand, all terms such as "up to," "at least," "greater than," "less than," etc., are inclusive of the recited numbers and refer to ranges that can be subsequently divided into subranges as described above. Finally, as one of ordinary skill in the art will understand, a range includes each individual member. Thus, for example, a group having 1 to 3 cells refers to a group having 1, 2, or 3 cells. Similarly, a group having 1 to 5 cells refers to groups having 1, 2, 3, 4, or 5 cells, and so forth.

[0020] In the context of describing the materials and methods described herein (particularly in the context of the claims which follow), the use of the terms "a," "an," "the," and similar directives should be construed to cover both the singular and the plural unless otherwise indicated herein or clearly contradicted by context.

[0021] The term "about" is used throughout this specification to describe and explain small variations. For example, the term "about" means ±5% or less, e.g., ±2% or less, ±1% or less, ±0.5% or less, ±0.2% or less, ±0.1% or less, or ±0.05% or less. All numerical values ​​herein are modified by the term "about," whether or not expressly indicated. Values ​​modified by the term "about" necessarily include the specific value in question. For example, "about 5.0" necessarily includes 5.0.

[0022] In the following sections, various aspects of the present subject matter are defined in more detail. Each aspect so defined may be combined with any other aspect or aspects, unless clearly indicated to the contrary. Any feature indicated as being preferred or advantageous may be combined with any other feature or features indicated as being preferred or advantageous.

[0023] References throughout this specification to "one embodiment" or "an embodiment" mean that a feature, structure, or characteristic described with respect to that embodiment is included in at least one embodiment of the claimed invention. Thus, appearances of the phrases "in one embodiment" or "in an embodiment" in various places throughout this specification do not necessarily all refer to the same embodiment, but may. Furthermore, in one or more embodiments, features, structures, or characteristics can be combined in any suitable manner, as would be apparent to one of ordinary skill in the art from this disclosure. Furthermore, as one of ordinary skill in the art will appreciate, while some embodiments described herein include some features and not other features included in other embodiments, combinations of features from different embodiments are contemplated within the scope of the present subject matter and form different embodiments. For example, in the appended claims, any of the claimed embodiments can be used in any combination.

[0024] Although the embodiments disclosed herein have been described with reference to exemplary embodiments, it should be understood that these embodiments are merely illustrative of the principles and applications of the claimed invention. It will be apparent to those skilled in the art that various modifications and variations can be made in the method and apparatus of the claimed invention without departing from the spirit and scope of the claimed invention. Accordingly, the claimed invention is intended to include modifications and variations that come within the scope of the appended claims and their equivalents, and the above-described embodiments are presented by way of example, not limitation. All patents and publications cited herein are incorporated by reference as if set forth for their specific teachings, unless a statement of incorporation otherwise specifically indicates otherwise.

[0025] All methods described herein can be performed in any suitable order, unless otherwise indicated herein, or unless otherwise indicated otherwise clearly contradicted by context. The use of any examples or exemplary language (e.g., "such as") provided herein is intended merely to better illustrate the materials and methods and is not intended to limit the scope unless otherwise claimed.

[0026] The term "coating" as used herein refers to any surface treatment applied to paper. The term "barrier properties" as used herein refers to increased resistance of paper to various materials such as air, oil, grease, etc., and improved surface strength. The term "blocking resistance" as disclosed herein refers to the ability of a coating applied to two surfaces not to adhere to itself upon contact or when pressure is applied. The term "oil and / or grease resistance" as disclosed herein refers to the ability of a substrate on which a coating is applied to resist the formation of surface spots or stains or penetration of the substrate by oil / grease.

[0027] In the present claimed invention, a paper or paperboard substrate or paper product, as used herein, can be any article of manufacture comprising paper, at least a portion of which is coated according to the present claimed invention. The present claimed invention encompasses paper products made of one or more layers, such as paper laminates and plastic laminates. The terms "repulpable" or "repulpability," as used interchangeably herein, refer to the ability of a coated paper or paperboard substrate to undergo subsequent rewetting and fiberization operations to form a paper sheet. The terms "recycled" or "recyclability," as used interchangeably herein, refer to the ability of used treated paper and paperboard to be converted into new paper and paperboard.

[0028] As used herein, the term "paper-based substrate" or "paperboard substrate" refers to any type of cellulose fiber-based product that can be folded manually or machine.

[0029] As used herein, the term "aqueous" means a significant proportion of water as the primary dispersion medium other than organic solvents.

[0030] The use of (meth) in a monomer or repeat unit indicates an optional methyl group. The term "copolymer" is meant to include block or random copolymers obtainable by radical polymerization.

[0031] In the presently claimed invention, the coating of the presently claimed invention can be applied to paper or paperboard by any conventional coating and surface sizing technique, including but not limited to, size presses, tabs, gate rolls, and spray applicators.

[0032] The terms "% by weight" or "% by weight (wt.%)" used in the present claimed invention are based on the total weight of the composition. Furthermore, the sum of the wt. % of all compounds listed below in each component equals 100 wt. %.

[0033] The term "substituted" refers to an organic group, as defined below (e.g., an alkyl group), in which one or more bonds to a hydrogen atom are replaced with a bond to a non-hydrogen or non-carbon atom. Substituted groups also include groups in which one or more bonds to a carbon or hydrogen atom are replaced with a bond containing one or more double or triple bonds to a heteroatom. Thus, a substituted group is substituted with one or more substituents, unless otherwise specified. In some embodiments, a substituted group is substituted with 1, 2, 3, 4, 5, or 6 substituents. Examples of substituents include halogens (i.e., F, Cl, Br, and I); hydroxyl; alkoxy, alkenoxy, alkynoxy, aryloxy, aralkyloxy, heterocyclyloxy, and heterocyclylalkoxy groups; carbonyl (oxo); carboxyl; esters; ethers; urethanes; hydroxylamines; alkoxyamines; aralkoxyamines; thiols; sulfides; sulfoxides; sulfones; sulfonyls; sulfonamides; amines; N-oxides; hydrazines; hydrazides; hydrazones; azides; amides; ureas; enamines; imides; isocyanates; isothiocyanates; cyanates; thiocyanates; imines; nitro groups; nitriles (i.e., CN), and the like. As used herein, alkyl groups include straight-chain and branched alkyl groups having 1 to 20 carbon atoms, typically 1 to 12 carbons, or in some embodiments, 1 to 8, 1 to 6, or 1 to 4 carbon atoms. In some embodiments, the alkyl group comprises a straight chain and / or branched alkyl group having 12 to 18 carbons.

[0034] The alkyl groups described herein further include cycloalkyl groups having 3 to 8 ring members. Examples of linear alkyl groups include alkyl groups having 1 to 8 carbon atoms, such as methyl, ethyl, n-propyl, n-butyl, n-pentyl, n-hexyl, n-heptyl, and n-octyl. Examples of branched alkyl groups include, but are not limited to, isopropyl, isobutyl, sec-butyl, tert-butyl, neopentyl, isopentyl, and 2,2-dimethylpropyl. In some embodiments, the branched alkyl group has at least 8 carbon atoms. As used herein, cycloalkyl groups are cyclic alkyl groups, including bridged cycloalkyl groups, such as, but not limited to, cyclopropyl, cyclobutyl, cyclopentyl, cyclohexyl, cycloheptyl, and cyclooctyl groups. Representative substituted alkyl groups can be unsubstituted or substituted.

[0035] One aspect of the claimed invention is: (i) at least one first polymer in an amount ranging from about 10% to about 90% by weight derived from at least one first monomer selected from an ethylenically substituted aromatic compound and at least one second monomer selected from the group consisting of (meth)acrylonitrile, (meth)acrylamide, (meth)acrylic acid, alkyl (meth)acrylate, and mixtures thereof; and (ii) at least one second polymer in an amount ranging from about 10% to about 90% by weight, comprising the reaction product of a partially neutralized acid-functional support resin with at least one ethylenically unsaturated monomer selected from the group consisting of olefins, monovinylidene aromatic compounds, α,β-ethylenically unsaturated carboxylic acids and esters thereof, ethylenically unsaturated dicarboxylic acid anhydrides, and mixtures thereof; Including, All weight percentages refer to the aqueous composition and are based on the total weight of the aqueous composition.

[0036] In one embodiment of the present claimed invention, the aqueous compositions disclosed herein are provided as coatings that impart barrier properties to substrates, including, but not limited to, paper and paper products. In another embodiment of the present claimed invention, the aqueous compositions disclosed herein are provided as coatings that impart barrier properties to paper and paper products. In yet another embodiment of the present claimed invention, there is provided the use of the aqueous compositions disclosed herein for coatings. In the present claimed invention, the aqueous compositions disclosed herein are interchangeably referred to as barrier compositions.

[0037] In one embodiment of the presently claimed invention, the paper coating composition comprises: (i) at least one first polymer in an amount ranging from about 10% to about 90% by weight derived from at least one first monomer selected from an ethylenically substituted aromatic compound and at least one second monomer selected from the group consisting of (meth)acrylonitrile, (meth)acrylamide, (meth)acrylic acid, alkyl (meth)acrylate, and mixtures thereof; and (ii) at least one second polymer in an amount ranging from about 10% to about 90% by weight, comprising the reaction product of a partially neutralized acid-functional support resin with at least one ethylenically unsaturated monomer selected from the group consisting of olefins, monovinylidene aromatic compounds, α,β-ethylenically unsaturated carboxylic acids and esters thereof, ethylenically unsaturated dicarboxylic acid anhydrides, and mixtures thereof; Including, All weight percentages are based on the total weight of the aqueous composition.

[0038] In one embodiment of the presently claimed invention, the at least one first polymer is present in an amount ranging from about 50% to about 90% by weight, based on the total weight of the aqueous composition.

[0039] In another embodiment of the presently claimed invention, the at least one second polymer is present in an amount ranging from about 10% to about 50% by weight, based on the total weight of the aqueous composition.

[0040] In another embodiment of the presently claimed invention, the aqueous composition described herein comprises at least one first polymer derived from at least one first monomer selected from ethylenically substituted aromatic compounds, and at least one second monomer selected from the group consisting of (meth)acrylonitrile, (meth)acrylamide, (meth)acrylic acid, alkyl (meth)acrylate, and mixtures thereof, in an amount ranging from about 10% to about 90% by weight; and about 0.1% to about 20% by weight of a wax, all weight percentages being based on the total weight of the aqueous composition.

[0041] In yet another embodiment of the presently claimed invention, the aqueous compositions disclosed herein, when dry, have a water absorption capacity of about 5 g / m 2 / 20 minutes or less, and exhibits sufficient blocking resistance to avoid substrate damage. In another embodiment of the presently claimed invention, paper coated with the aqueous composition disclosed herein exhibits blocking resistance at 50°C and 60 psi for 24 hours, i.e., two sheets of a coated-to-paper (face-to-back, FB) laminate or a coated-to-coated (face-to-face, FF) laminate, each coated with a polymeric binder.

[0042] In one embodiment of the claimed invention, the ratio of the volume average particle size of the at least one first polymer to the volume average particle size of the at least one second polymer is in the range of about 20:1 to 2:1. In another embodiment of the claimed invention, the ratio of the volume average particle size of the at least one first polymer to the volume average particle size of the at least one second polymer is in the range of about 10:1 to 2:1. In another embodiment of the claimed invention, the ratio of the volume average particle size of the at least one first polymer to the volume average particle size of the at least one second polymer is in the range of 8:1 to 2:1. In another embodiment of the claimed invention, the ratio of the volume average particle size of the at least one first polymer to the volume average particle size of the at least one second polymer is in the range of 4:1 to 2:1 or in the range of 3:1 to 2:1.

[0043] In another embodiment of the presently claimed invention, the viscosity of the aqueous composition is in the range of about 100 cP to about 2500 cP. In yet another embodiment of the presently claimed invention, the viscosity of the aqueous composition is in the range of about 100 cP to about 1500 cP. In yet another embodiment of the presently claimed invention, the viscosity of the aqueous composition is in the range of about 100 cP to about 500 cP. All measurements are taken at 23°C using a viscometer equipped with a No. 2 spindle at 50 rpm.

[0044] In one embodiment of the claimed invention, the solids content of the aqueous composition is in the range of about 20% to about 70% by mass. In another embodiment of the claimed invention, the solids content of the aqueous composition is in the range of about 20% to about 60% by mass. In another embodiment of the claimed invention, the solids content of the aqueous composition is in the range of about 40% to about 60% by mass. All of these are based on the total mass of the aqueous composition.

[0045] In one embodiment of the presently claimed invention, the first polymer present in the aqueous composition has a weight average molecular weight (Mw) of at least 100 kDa, such as from 20 kDa to 500 kDa, from 50 kDa to 250 kDa, or from 100 kDa to 200 kDa, as determined by gel permeation chromatography.

[0046] In one embodiment of the claimed invention, the volume average particle diameter of the first polymer is in the range of about 90 nm to about 400 nm. In another embodiment of the claimed invention, the volume average particle diameter of the first polymer is in the range of about 90 nm to about 300 nm. In another embodiment of the claimed invention, the volume average particle diameter of the first polymer is in the range of about 100 nm to about 200 nm. Both are measured by dynamic light scattering technology.

[0047] In one embodiment of the claimed invention, the viscosity of the first polymer ranges from about 100 cP to about 2500 cP. In another embodiment of the claimed invention, the viscosity of the first polymer ranges from about 200 cP to about 2000 cP. In another embodiment of the claimed invention, the viscosity of the first polymer ranges from about 200 cP to about 1000 cP. All are measured at 23°C using a viscometer equipped with a No. 2 spindle at 50 rpm.

[0048] In the presently claimed invention, the first monomer of the first polymer can comprise any aromatic monomer known in the art. In another embodiment of the presently claimed invention, the first monomer is a vinyl aromatic monomer. In yet another embodiment of the presently claimed invention, the first monomer is an ethylenically substituted aromatic compound. Examples of ethylenically substituted aromatic compounds can include, but are not limited to, vinyl aromatic monomers, such as styrene, alkyl styrenes such as α- and p-methylstyrene, α-butylstyrene, 4-n-butylstyrene, and 4-n-decylstyrene, as well as vinyl toluene, indene, methylindene, or combinations thereof.

[0049] In one embodiment of the presently claimed invention, the first polymer can be derived from at least 40% by weight or more, at least 45% by weight or more, at least 50% by weight or more, at least 55% by weight or more, at least 60% by weight or more, at least 65% by weight or more, at least 70% by weight or more, at least 75% by weight or more, at least 80% by weight or more, or at least 5% by weight or more aromatic monomers.

[0050] In other embodiments of the claimed invention, the first polymer is derived from 95% or less, 90% or less, 85% or less, 80% or less, 75% or less, 70% or less, 65% or less, or 60% or less by weight of aromatic monomers. In yet other embodiments of the claimed invention, the first polymer can be derived from 40% to 95%, 40% to 90%, 45% to 90%, 45% to 80%, or 50% to 80% by weight of aromatic monomers. In other embodiments of the claimed invention, the first polymer can be derived from 2% to 40%, 5% to 40%, 5% to 35%, 5% to 30%, or 5% to 25% by weight of aromatic monomers.

[0051] In the presently claimed invention, the second monomer of the first polymer can comprise any ethylenically unsaturated aliphatic monomer known in the art. In one embodiment of the presently claimed invention, the second monomer is selected from the group consisting of (meth)acrylonitrile, (meth)acrylamide, (meth)acrylic acid, alkyl (meth)acrylate, and mixtures thereof. Examples of alkyl (meth)acrylate monomers include esters of α,β-monoethylenically unsaturated monocarboxylic acids having 3 to 6 carbon atoms with alkanols having 1 to 12 carbon atoms, such as acrylic acid, methacrylic acid, maleic acid, fumaric acid, or itaconic acid with C1 to C6 alkyl (meth)acrylates. 12 , C1~C 10, C1-C8, or C1-C4 alkanols. In some examples, the alkyl (meth)acrylate monomer can include, but is not limited to, methyl acrylate, ethyl acrylate, butyl acrylate, 2-ethylhexyl acrylate, methyl methacrylate, or combinations thereof.

[0052] In one embodiment of the claimed invention, the first polymer can be derived from 5% or more, 10% or more, 15% or more, 20% or more, 25% or more, or 30% or more by weight of the second monomer. In another embodiment of the claimed invention, the copolymer can be derived from 60% or less, 55% or less, 50% or less, 45% or less, 40% or less, or 35% or less by weight of the second monomer. In yet another embodiment of the claimed invention, the copolymer can be derived from 5% to 60%, 10% to 60%, 10% to 50%, 15% to 600%, or 15% to 50% by weight of the second monomer.

[0053] In one embodiment of the claimed invention, the amount of the first monomer is in the range of about 10% to about 50% by weight, and the amount of the second monomer is in the range of about 10% to about 90% by weight, both relative to the total weight of the first polymer. In another embodiment of the claimed invention, the amount of the first monomer is in the range of about 10% to about 40% by weight, and the amount of the second monomer is in the range of about 20% to about 90% by weight, both relative to the total weight of the first polymer. In yet another embodiment of the claimed invention, the amount of the at least one first monomer is in the range of about 10% to about 30% by weight, and the amount of the at least one second monomer is in the range of about 70% to about 90% by weight, both relative to the total weight of the first polymer. The second monomer can be a mixture of at least two different monomers.

[0054] In the presently claimed invention, the first polymer may further be derived from additional monomers. Examples of additional monomers include, but are not limited to, carboxylic acid monomers such as α-monoethylenically unsaturated monocarboxylic / dicarboxylic acids, β-monoethylenically unsaturated monocarboxylic / dicarboxylic acids, citraconic acid, styrene carboxylic acid, (meth)acrylic acid, itaconic acid, fumaric acid, crotonic acid, dimethacrylic acid, ethylacrylic acid, allylacetic acid, vinylacetic acid, maleic acid, mesaconic acid, methylenemalonic acid, and citraconic acid. Further examples of additional monomers include anhydrides of α,β-monoethylenically unsaturated monocarboxylic and dicarboxylic acids such as maleic anhydride, itaconic anhydride, and methylmalonic anhydride; (meth)acrylonitrile; vinyl and vinylidene halides such as vinyl chloride and vinylidene chloride; C1-C 18 Vinyl esters of monocarboxylic or dicarboxylic acids, such as vinyl acetate, vinyl propionate, vinyl n-butyrate, vinyl laurate, and vinyl stearate; C1-C4 hydroxyalkyl esters of C3-C6 monocarboxylic or dicarboxylic acids, in particular acrylic acid, methacrylic acid, or maleic acid, or their derivatives alkoxylated with 2 to 50 moles of ethylene oxide, propylene oxide, butylene oxide, or mixtures thereof, or C1-C alkoxylated derivatives of these acids with 2 to 50 moles of ethylene oxide, propylene oxide, butylene oxide, or mixtures thereof. 18 These include, but are not limited to, esters with alcohols (such as hydroxyethyl (meth)acrylate, hydroxypropyl (meth)acrylate, and methyl polyglycol acrylate); and monomers containing glycidyl groups (such as glycidyl methacrylate).

[0055] Further examples of usable additional monomers or comonomers include linear 1-olefins, branched 1-olefins, or cyclic olefins (e.g., ethene, propene, butene, isobutene, pentene, cyclopentene, hexene, and cyclohexene); vinyl alkyl ethers and allyl alkyl ethers having 1 to 40 carbon atoms in the alkyl group, which may carry further substituents such as hydroxyl groups, amino or dialkylamino groups, or one or more alkoxylated groups, such as methyl vinyl ether, ethyl vinyl ether, propyl vinyl ether, isobutyl vinyl ether, 2-ethylhexyl vinyl ether, vinyl cyclohexyl ether, vinyl 4-hydroxybutyl ether, decyl vinyl ether, dodecyl vinyl ether, octadecyl vinyl ether, 2-(diethylamino)ethyl vinyl ether, 2-(di-n-butylamine)ethyl vinyl ether, methyl diglycol vinyl ether, and the corresponding allyl ethers; sulfofunctional monomers (e.g., allyl sulfonic acid, methallyl sulfonic acid, styrene). benzenesulfonates, vinylsulfonic acid, allyloxybenzenesulfonic acid, 2-acrylamido-2-methylpropanesulfonic acid, and their corresponding alkali metal or ammonium salts, sulfopropyl acrylate, and sulfopropyl methacrylate; phosphorus-containing monomers (e.g., dihydrogen phosphate esters of alcohols, where the alcohol contains a polymerizable vinyl group or an olefin group, allyl phosphate, phosphoalkyl(meth)acrylates, such as 2-phosphoethyl(meth)acrylate (PEM), 2-phosphopropyl( Monophosphates or diphosphates of hydroxyalkyl (meth)acrylates, 3-phosphopropyl (meth)acrylate, and phosphobutyl (meth)acrylate, 3-phospho-2-hydroxypropyl (meth)acrylate, bis(hydroxymethyl)fumarate or itaconate; phosphates of hydroxyalkyl (meth)acrylates, 2-hydroxyethyl (meth)acrylate, 3-hydroxypropyl (meth)acrylate, ethylene oxide condensates of (meth)acrylates, H2C=C(CH3)COO(CH2CHO) nP(O)(OH)2 and similar propylene and butylene oxide condensates (where n is an amount from 1 to 50), phosphoalkyl crotonates, phosphoalkyl maleates, phosphoalkyl fumarates, phosphodialkyl (meth)acrylates, phosphodialkyl crotonates, vinyl phosphonic acid, allyl phosphonic acid, 2-acrylamido-2-methylpropanephosphinic acid, α-phosphonostyrene, 2-methylacrylamido-2-methylpropanephosphinic acid, (hydroxy)phosphinyl alkyl (meth)acrylates, (hydroxy)phosphinyl methyl methacrylates, and combinations thereof; alkylamino alkyl (meth)acrylates or or alkylaminoalkyl(meth)acrylamides, or their quaternized products (e.g., 2-(N,N-dimethylamino)ethyl(meth)acrylate, 3-(N,N-dimethylamino)propyl(meth)acrylate, 2-(N,N,N-trimethylammonium)ethyl(meth)acrylate chloride, 2-dimethylaminoethyl(meth)acrylamide, acrylonitrile, 3-dimethylaminopropyl(meth)acrylamide, and 3-trimethylammoniumpropyl(meth)acrylamidochloride); C1-C 30Examples of suitable monomers include, but are not limited to, allyl esters of monocarboxylic acids; N-vinyl compounds (e.g., N-vinylformamide, N-vinyl-N-methylformamide, N-vinylpyrrolidone, N-vinylimidazole, 1-vinyl-2-methylimidazole, 1-vinyl-2-methylimidazoline, N-vinylcaprolactam, vinylcarbazole, 2-vinylpyridine, and 4-vinylpyridine); monoalkyl itaconates; monoalkyl maleates; hydrophobic branched ester monomers; silyl group-containing monomers (e.g., trimethoxysilylpropyl methacrylate), vinyl esters of branched monocarboxylic acids having a total of 8 to 12 carbon atoms in the acid residue moiety and a total of 10 to 14 carbon atoms, such as vinyl 2-ethylhexanoate, vinyl neononanoate, vinyl neodecanoate, vinyl neoundecanoate, vinyl neododecanoate, and mixtures thereof, and copolymerizable surfactant monomers (e.g., monomers sold under the trade name ADEKA REASOAP).

[0056] The additional monomer used to form the copolymer may include, but is not limited to, a crosslinking monomer. For example, the crosslinking monomer may include diacetone acrylamide (DAAM), a self-crosslinking monomer, such as a monomer containing a 1,3-diketo group, or a silane crosslinker. Examples of the monomer containing a 1,3-diketo group include acetoacetoxyalkyl (meth)acrylates, such as acetoacetoxyethyl (meth)acrylate (AAEM), acetoacetoxypropyl (meth)acrylate, acetoacetoxybutyl (meth)acrylate, and 2,3-di(acetoacetoxy)propyl (meth)acrylate; allyl acetoacetate; vinyl acetoacetate; and combinations thereof. Examples of suitable silane crosslinkers include 3-methacryloxypropyltrimethoxysilane, 3-mercaptopropyltrimethoxysilane, vinyltriethoxysilane, and polyvinylsiloxane oligomers such as DYNASYLAN® 6490, a polyvinylsiloxane oligomer derived from vinyltrimethoxysilane, and DYNASYLAN® 6498, a polyvinylsiloxane oligomer derived from vinyltriethoxysilane, both commercially available from Evonik Degussa GmbH (Essen, Germany). Crosslinkable monomers described herein can further include divinylbenzene; 1,4-butanediol diacrylate; methacrylic anhydride; and monomers containing urea groups (e.g., ureidoethyl (meth)acrylate, acrylamidoglycolic acid, and methacrylamidoglycolate methyl ether). Further examples of crosslinking monomers include N-alkylolamides of α,β-monoethylenically unsaturated carboxylic acids having 3 to 10 carbon atoms and their esters with alcohols having 1 to 4 carbon atoms (e.g., N-methylolacrylamide and N-methylolmethacrylamide); glyoxal-based crosslinkers; monomers containing two vinyl groups; monomers containing two vinylidene groups; and monomers containing two alkenyl groups. Other exemplary crosslinking monomers include crosslinks of dihydric and trihydric alcohols with α,β-monoethylenically unsaturated monocarboxylic acids (acrylic acid and methacrylic acid are useful). Examples of such monomers containing two non-conjugated ethylenically unsaturated double bonds include alkylene glycol diacrylates and dimethacrylates, such as ethylene glycol diacrylate, 1,3-butylene glycol diacrylate, 1,4-butylene glycol diacrylate, and propylene glycol diacrylate, vinyl methacrylate, vinyl acrylate, allyl methacrylate, allyl acrylate, diallyl maleate, diallyl fumarate, and methylene bisacrylamide. In some examples, the copolymer may be derived from 0% to 5% by weight of one or more crosslinking monomers. In one embodiment of the claimed invention, the crosslinking agent may be used in an amount of 0.01% to 5% by weight, based on the weight of the copolymer.

[0057] In one embodiment of the presently claimed invention, the additional monomer in the copolymers disclosed herein may be present in a range of about 10% by weight or less, 7.5% by weight or less, 5% by weight or less, 4% by weight or less, 3% by weight or less, 2% by weight or less, 1.5% by weight or less, 1% by weight or less, or 0.5% by weight or less, based on the total weight of the copolymer.

[0058] In one embodiment of the claimed invention, the first polymer is derived from only one first monomer and at least one second monomer. In another embodiment of the claimed invention, the first polymer is derived from at least one first monomer and only one second monomer. In yet another embodiment of the claimed invention, the at least one first monomer is different from the at least one second monomer. For example, the first polymer can be derived from styrene, acrylonitrile, and other monomers. In another embodiment of the claimed invention, the first polymer can be derived from styrene, one or more esters of an α,β-monoethylenically unsaturated monocarboxylic acid monomer (e.g., butyl acrylate, 2-ethylhexyl acrylate, ethyl acrylate, methyl acrylate, methyl methacrylate, or a combination thereof), and an α,β-monoethylenically unsaturated monocarboxylic acid monomer.

[0059] In one embodiment of the presently claimed invention, the second polymer comprises a partially neutralized acid-functional support resin and at least one ethylenically unsaturated monomer selected from the group consisting of olefins, monovinylidene aromatic compounds, α,β-ethylenically unsaturated carboxylic acids and esters thereof, ethylenically unsaturated dicarboxylic acid anhydrides, and mixtures thereof. In another embodiment of the presently claimed invention, the partially neutralized acid-functional support resin is selected from ammonium salts of modified acrylic copolymers, amine salts of modified acrylic copolymers, and mixtures thereof. Examples of modified acrylic copolymers include, but are not limited to, polymers derived from (meth)acrylic acid monomers, (meth)acrylate monomers, vinyl aromatic monomers, or combinations thereof. In another embodiment of the presently claimed invention, the acid functional support resin or solid grade oligomer is selected from the group consisting of styrene, alkylstyrene, e.g., α-methylstyrene, α,β-monoethylenically unsaturated carboxylic acids having 3 to 6 carbon atoms, salts or esters of α,β-monoethylenically unsaturated carboxylic acids having 3 to 6 carbon atoms with alkanols having 1 to 12 carbon atoms, e.g., acrylic acid, methacrylic acid, maleic acid, fumaric acid, or itaconic acid with C1 to C 20 , C1~C12 , C1-C8, or C1-C4 alkanols; alkoxy(meth)acrylates, or combinations thereof. Examples of salts or esters of α,β-monoethylenically unsaturated carboxylic acids include butyl acrylate, 2-ethylhexyl acrylate, ethyl acrylate, methyl acrylate, methyl methacrylate, alkoxy(meth)acrylates such as carbitol methacrylate, or mixtures thereof. In one embodiment of the presently claimed invention, the solid-grade oligomer is an ammonium salt of a styrene-acrylic copolymer, an amine salt of a styrene-acrylic copolymer, or a combination thereof.

[0060] In one embodiment of the presently claimed invention, the weight average molecular weight of the second polymer, as determined by gel permeation chromatography, is in the range of about 100 kDa to about 1,000 kDa, e.g., 200 kDa to 1,000 kDa, 300 kDa to 900 kDa, or 500 kDa to 900 kDa.

[0061] In one embodiment of the claimed invention, the volume average particle diameter of the second polymer is in the range of about 50 nm to about 200 nm. In another embodiment of the claimed invention, the volume average particle diameter of the second polymer is in the range of about 50 nm to about 150 nm. In another embodiment of the claimed invention, the volume average particle diameter of the second polymer is in the range of about 50 nm to about 100 nm. Both are measured by dynamic light scattering technology.

[0062] In one embodiment of the claimed invention, the viscosity of the second polymer ranges from about 1000 cP to about 5000 cP. In another embodiment of the claimed invention, the viscosity of the second polymer ranges from about 1000 cP to about 4000 cP. In another embodiment of the claimed invention, the viscosity of the second polymer ranges from about 1000 cP to about 2000 cP. All are measured at 20°C using a viscometer equipped with a No. 2 spindle at 50 rpm.

[0063] In one embodiment of the claimed invention, the weight average molecular weight (Mw) of the partially neutralized acid-functional support resin present in the composition can be 20 kDa or less, e.g., from 2 kDa to 20 kDa, from 2 kDa to 15 kDa, or from 2 kDa to 10 kDa. In another embodiment of the claimed invention, the weight average molecular weight of the copolymer present in the composition can be 20 kDa or less, 18 kDa or less, 15 kDa or less, 12 kDa or less, 10 kDa or less, 8 kDa or less, or 7 kDa or less, all as determined by gel permeation chromatography.

[0064] In another embodiment of the presently claimed invention, the number average molecular weight (Mn) of the partially neutralized acid-functional support resin present in the composition can be 2.0 kDa or less, e.g., 2 kDa to 20 kDa, 2 kDa to 15 kDa, or 2 kDa to 10 kDa. In yet another embodiment of the presently claimed invention, the number average molecular weight of the copolymer present in the composition can be 20 kDa or less, 18 kDa or less, 15 kDa or less, 12 kDa or less, 10 kDa or less, 8 kDa or less, or 7 kDa or less, all as determined by gel permeation chromatography.

[0065] In one embodiment of the claimed invention, partial neutralization refers to neutralization of from about 5 mol% to about 95 mol% of the acid groups on the acid-functional resin. In another embodiment of the claimed invention, partial neutralization refers to neutralization of from about 20 mol% to about 95 mol% of the acid groups on the acid-functional resin. In various embodiments, this can include at least about 5 mol% of the acid groups, at least about 10 mol% of the acid groups, from about 10 mol% to about 95 mol% of the acid groups, from about 8 mol% to about 85 mol% of the acid groups, from about 15 mol% to about 50 mol% of the acid groups, or from about 35 mol% to about 50 mol% of the acid groups. In yet another embodiment of the claimed invention, partial neutralization refers to neutralization of about 30 mol% of the acid groups on the acid-functional resin.

[0066] In one embodiment of the presently claimed invention, the partially neutralized acid-functional support resin is neutralized with a base selected from the group consisting of ammonia, sodium hydroxide, potassium hydroxide, an organic amine, and mixtures thereof. In one embodiment of the presently claimed invention, the second polymer comprises the partially neutralized acid-functional support resin in an amount of from about 5% to about 50% by weight, and at least one ethylenically unsaturated monomer in an amount ranging from about 5% to about 50% by weight, both based on the total weight of the second polymer. In another embodiment of the presently claimed invention, the second polymer comprises the partially neutralized acid-functional support resin in an amount of from about 10% to about 50% by weight, and at least one ethylenically unsaturated monomer in an amount ranging from about 10% to about 40% by weight, both based on the total weight of the second polymer. In yet another embodiment of the presently claimed invention, the second polymer comprises the partially neutralized acid-functional support resin in an amount of from about 10% to about 30% by weight, and at least one ethylenically unsaturated monomer in an amount ranging from about 10% to about 30% by weight, both based on the total weight of the second polymer.

[0067] The partially neutralized acid-functional support resin can react and become covalently bonded to the second polymer during polymerization of the first and second monomers. In one embodiment of the present claimed invention, the partially neutralized acid-functional support resin is grafted to the second polymer. In one embodiment of the present claimed invention, the aqueous composition is derived from 8% to 40%, e.g., 10% to 40%, 10% to 35%, 15% to 35%, or 20% to 30%, by weight of the partially neutralized acid-functional support resin, based on the total weight of solids in the composition.

[0068] In one embodiment of the claimed invention, the aqueous composition is derived from 5% to 85% by weight of styrene, e.g., 10% to 70% by weight, 15% to 65% by weight, 20% to 60% by weight, or 25% to 50% by weight. In another embodiment of the claimed invention, the aqueous composition is derived from 5% to 60% by weight of butadiene, e.g., 10% to 60% by weight, 15% to 65% by weight, 25% to 60% by weight, 25% to 50% by weight, or 30% to 45% by weight. In another embodiment of the claimed invention, the aqueous composition is derived from 10% to 40% by weight of a solids-grade oligomer, e.g., 10% to 35% by weight, 15% to 35% by weight, or 20% to 30% by weight. In yet another embodiment of the presently claimed invention, the copolymer may be derived from one or more monomers in addition to styrene and (meth)acrylate ester, such as (meth)acrylonitrile, (meth)acrylamide, and / or carboxylic acid monomers (e.g., (meth)acrylic acid).

[0069] In one embodiment of the claimed invention, the first monomer comprises styrene and the second monomer comprises a (meth)acrylate monomer. For example, the (meth)acrylic acid monomer can be an ester of (meth)acrylic acid, such as butyl acrylate, 2-ethylhexyl acrylate, ethyl acrylate, methyl acrylate, or methyl methacrylate. In another embodiment of the claimed invention, the copolymer is derived from 5% to 85% by weight, e.g., 10% to 70%, 15% to 65%, 20% to 60%, or 25% to 50% by weight, of styrene. In another embodiment of the claimed invention, the copolymer is derived from 5% to 60% by weight, e.g., 10% to 60%, 15% to 65%, 25% to 60%, 25% to 50%, or 30% to 45% by weight of the (meth)acrylate monomer. In another embodiment of the presently claimed invention, the copolymer is derived from 10% to 40%, e.g., 10% to 35%, 15% to 35%, or 20% to 30%, by weight of the solids-grade oligomer. In yet another embodiment of the presently claimed invention, the copolymer may be derived from one or more monomers, in addition to styrene and (meth)acrylate monomers, such as (meth)acrylamide, carboxylic acid monomers (e.g., (meth)acrylic acid), phosphate monomers (e.g., PEM), acetoacetoxy monomers (e.g., AAEM), or another functional monomer.

[0070] The aqueous compositions disclosed herein can be prepared by any polymerization method known in the art. In one embodiment of the claimed invention, the compositions disclosed herein are prepared by dispersion polymerization, miniemulsion polymerization, or emulsion polymerization. For example, the aqueous compositions disclosed herein can be prepared by polymerizing a first monomer and a second monomer in the presence of a solid-grade oligomer using free-radical aqueous emulsion polymerization. The emulsion polymerization can be an aqueous emulsion containing water, a first monomer, a second monomer, a solid-grade oligomer, an optional emulsifier, or a combination thereof. In one embodiment of the claimed invention, the polymerization medium is an aqueous medium. Solvents other than water can be used in the emulsion. Emulsion polymerization can be carried out as a batch process, a semi-batch process, or a continuous process. In one embodiment, a portion of the monomers can be heated to the polymerization temperature and partially polymerized, and then the remainder of the polymerization batch can be fed to the polymerization section continuously, in stages, or by superimposing concentration gradients. As one skilled in the art will readily appreciate, the process can use a single reactor or a series of reactors. For example, a review of heterophase polymerization techniques is provided by M. Antonelli and K. Tauer, Macromol. Chem. Phys. 2003, Vol. 204, pp. 207-19.

[0071] In one embodiment of the claimed invention, an aqueous dispersion is provided comprising a second polymer and a partially neutralized acid-functional support resin. In another embodiment of the claimed invention, the aqueous dispersion can be prepared by initially charging a reactor with water, a partially neutralized acid-functional support resin, and, optionally, at least one surfactant. A seed latex may optionally be included in the reactor to facilitate initiation of polymerization and to promote the production of a polymer with a consistent particle size. Any seed latex suitable for the particular monomer reaction can be used, such as a polystyrene seed. The initial charge may also include a chelating or complexing agent, such as ethylenediaminetetraacetic acid (EDTA). Other compounds, such as buffers, can be added to the reactor to achieve a desired pH for the emulsion polymerization reaction. For example, a base or basic salt, such as KOH or tetrasodium pyrophosphate, can be used to increase the pH, while an acid or acid salt can be used to decrease the pH. The initial charge can then be heated to a temperature at or near the reaction temperature, for example, 50°C to 100°C, e.g., 55°C to 95°C, 58°C to 90°C, 61°C to 85°C, 65°C to 80°C, or 68°C to 75°C.

[0072] After the initial charge, the first and second monomers to be used in the polymerization of the second polymer, as well as other monomers, if desired, can be continuously fed to the reactor in one or more monomer feed streams. These monomers can be fed as pre-emulsions in an aqueous medium, particularly when acrylate monomers are used in the polymerization. An initiator feed stream can be continuously added to the reactor as the monomer feed streams are added; however, if an initiator is used in the process, it may be desirable to add at least a portion of the initiator solution to the reactor before adding the monomer pre-emulsion. Typically, the monomer and initiator feed streams are continuously added to the reactor over a predetermined period of time (e.g., 1.5 to 5 hours) to cause polymerization of the monomers, thereby producing a copolymer dispersion. Optionally, a surfactant can be added at this time as part of the monomer or initiator feed stream, or they can be fed in separate feed streams. Additionally, one or more buffers can be included in the monomer or initiator feed streams or can be fed in separate feed streams to modify or maintain the pH of the reactor.

[0073] The monomer feed stream may contain one or more monomers. The first and second monomers may be fed in one or more feed streams, each containing one or more monomers used in the polymerization process. For example, styrene and acrylonitrile (if used) and other monomers may be fed in separate monomer feed streams or added as a pre-emulsion. It may also be advantageous to delay the feeding of certain monomers to impart specific polymer properties or to achieve a layered or multiphase structure (e.g., a core / shell structure).

[0074] The molecular weight of the first polymer and / or the second polymer can be adjusted by adding a small amount of a molecular weight regulator, for example, 0.01% to 4% by weight of the monomers to be polymerized. Examples of usable regulators include, but are not limited to, organic thio compounds such as tert-dodecyl mercaptan, allyl alcohol, and aldehydes.

[0075] The initiator feed stream may contain at least one initiator or initiator system used to cause polymerization of the monomers in the monomer feed stream. The initiator system may include water and other desired components suitable for initiating the monomer reaction. The initiator may be any initiator known in the art for use in emulsion reactions, such as an azo initiator; ammonium, potassium, or sodium persulfate; or a redox system typically containing an oxidizing agent and a reducing agent. Commonly used redox initiation systems are described, for example, by AS Sarac in Progress in Polymer Science 24, 1149-1204 (1999). Exemplary initiators include azo initiators and aqueous sodium persulfate. The initiator stream may optionally contain one or more buffers or pH adjusters.

[0076] In addition to the monomers and initiator, an anionic or nonionic surfactant (i.e., emulsifier) ​​may optionally be fed to the reactor. The surfactant may be fed in the initial reactor charge, in the monomer feed stream, in the aqueous feed stream, in a pre-emulsion, in the initiator stream, or a combination thereof. The surfactant may be fed to the reactor as a separate continuous stream. The surfactant may be fed in an amount of 1% to 5% by weight based on the total weight of the monomers and surfactant. In one embodiment of the presently claimed invention, the surfactant is fed in an amount less than 2% by weight.

[0077] Upon completion of polymerization, the polymer dispersion can be chemically stripped to reduce its residual monomer content. This stripping process can include a chemical stripping step and / or a physical stripping step. In some embodiments, the polymer dispersion is chemically stripped by continuously adding an oxidizing agent, such as a peroxide, e.g., t-butyl hydroperoxide, and a reducing agent, e.g., acetone sodium bisulfite, or another redox couple, to the reactor at an elevated temperature over a predetermined period of time (e.g., 0.5 hours). Suitable redox couples are described by AS Sarac in Progress in Polymer Science 24, 1149-1204 (1999). If necessary, an optional antifoaming agent can be added before or during the stripping step. In the physical stripping step, a water or steam flush can be used to further remove unpolymerized monomers in the dispersion. Upon completion of the stripping step, the pH of the polymer dispersion can be adjusted, and biocides or other additives can be added. Cationic, anionic, and / or amphoteric surfactants or polyelectrolytes may optionally be added to the product after the stripping step or later, if desired, to obtain cationic or anionic polymer dispersions.

[0078] When the polymerization reaction is complete and the stripping step is completed, the reactor temperature can be reduced.

[0079] In one embodiment of the claimed invention, particles of the resulting polymer dispersion (first polymer, second polymer, and / or mixture thereof) have a volume average particle size of 50 nm to 400 nm, for example, 50 nm to 380 nm, 50 nm to 360 nm, 50 nm to 340 nm, 50 nm to 320 nm, 90 nm to 300 nm, 120 nm to 380 nm, 140 nm to 360 nm, 160 nm to 340 nm, 200 nm to 320 nm, or 220 nm to 300 nm, or 240 nm to 280 nm. In some embodiments, the particles of the resulting copolymer dispersion have a number average particle size of 50 nm to 300 nm, e.g., 50 nm to 290 nm, 50 nm to 280 nm, 50 nm to 270 nm, 50 nm to 260 nm, 50 nm to 250 nm, 50 nm to 240 nm, 50 nm to 230 nm, 50 nm to 220 nm, 50 nm to 210 nm, 50 nm to 200 nm, 50 nm to 190 nm, or 50 nm to 180 nm. Particle size measurements are performed using dynamic light scattering measurements using a Microtrac nanoflex particle size analyzer.

[0080] The aqueous composition can be prepared as a dispersion comprising particles of the copolymer dispersed in water as the dispersed phase. In one embodiment of the claimed invention, an aqueous composition can be prepared having a total solids content of 20% to 70% by weight, e.g., 25% to 65%, 35% to 60%, or 40% to 50% by weight. In another embodiment of the claimed invention, the aqueous composition can have a total solids content of 45% or greater than 45% by weight. Despite the relatively high solids content of the aqueous dispersion, the aqueous dispersion disclosed herein can have a Brookfield viscosity of 100 cP to 2,500 cP at 23°C, e.g., 100 cP to 1,500 cP or 500 cP to 1,500 cP. Viscosity can be measured at 23°C using a viscometer equipped with a No. 2 spindle at 50 rpm.

[0081] The aqueous composition described herein may contain a wax. In one embodiment of the presently claimed invention, the wax is present in the aqueous composition in an amount of 0% to about 25% by weight, based on the total weight of the aqueous composition. For example, the wax is present in the aqueous composition in an amount of 0% to about 20% by weight; 0% to about 15% by weight; 0% to about 10% by weight; 0% to about 5% by weight; about 1% to about 25% by weight; about 1% to about 20% by weight; about 1% to about 15% by weight; about 1% to about 10% by weight; about 5% to about 25% by weight; about 5% to about 20% by weight; about 5% to about 15% by weight; about 5% to about 10% by weight; about 10% to about 25% by weight; about 10% to about 20% by weight; or about 10% to about 15% by weight. In one embodiment of the present claimed invention, the wax is present in the aqueous composition in an amount of 0, 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, 16, 17, 18, 19, 20, 21, 22, 23, 24, or 25% by weight, including increments therein. In one embodiment of the present claimed invention, the wax is present in the multi-phase polymer binder in an amount of about 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, 16, 17, 18, 19, 20, 21, 22, 23, 24, or 25% by weight, including increments therein.

[0082] In one embodiment of the presently claimed invention, the wax is an aqueous emulsion, also referred to herein as a wax emulsion. In one embodiment of the presently claimed invention, the wax emulsion is at least 1% by weight based on polymer solids. At least 1% by weight includes 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, 16, 17, 18, 19, 20, 21, 22, 23, 24, or 25% by weight (including increments therein) based on polymer solids. In one embodiment of the presently claimed invention, the wax emulsion can have a solids content of about 15% to about 60% by weight. In another embodiment of the presently claimed invention, the wax emulsion can have a solids content of about 25% to 40% by weight. In a non-limiting example, in a resin solution having a solids content of about 15% to about 60% by weight, the pH can range from about neutral to 9.5, and the Brookfield viscosity can range from 35 cps to 6,000 cps.

[0083] In another embodiment of the presently claimed invention, the wax emulsion comprises paraffin, polyethylene, polypropylene, microcrystalline wax, fluorinated wax, ethylene-propylene copolymer wax, or any combination of two or more thereof. Exemplary hydrophobic emulsions include, but are not limited to, paraffin / polyethylene wax emulsion, anionic paraffin / polyethylene wax emulsion, paraffin wax emulsion, ethoxylated paraffin wax emulsion, and surfactant-dispersed paraffin wax emulsion. Exemplary hydrophobic emulsions include, but are not limited to, JONCRYL® Wax 120, PETROLITE™ D-800, MICHEM® 62330, PETROLITE™ D-1038, JONCRYL® Wax 26, UNITHOX™ D-300, UNITHOX™ D-550, and UNITHOX™ 75.

[0084] The aqueous compositions described herein may contain a surfactant. In one embodiment of the presently claimed invention, the surfactant is anionic or nonionic. In one embodiment of the presently claimed invention, the surfactant is selected from the group consisting of alkyl sulfonates, alkyl benzene sulfonates, alkyl sulfates, alkyl benzene sulfates, phosphates, phosphinates, aliphatic carboxylates, and mixtures thereof.

[0085] In another embodiment of the claimed invention, the surfactant comprises at least one fatty alcohol alkoxylate. In another embodiment of the claimed invention, the at least one fatty alcohol alkoxylate is selected from fatty alcohol ethoxylates, fatty alcohol propoxylates, and any combination thereof. In yet another embodiment of the claimed invention, the surfactant comprises at least one ethylene oxide / propylene oxide block copolymer. In another embodiment of the claimed invention, the surfactant comprises at least one fatty alcohol ethoxylate. In yet another embodiment of the claimed invention, the surfactant comprises at least one or more alkyl sulfosuccinate ethoxylates. In another embodiment of the claimed invention, the surfactant comprises at least one alkyl sulfosuccinate ethoxylate and at least one fatty alcohol ethoxylate. In yet another embodiment of the claimed invention, the surfactant comprises at least one fatty alcohol having an alkyl chain length of from about 12 to about 18 carbons and a degree of ethoxylation of from about 10 to about 80 moles of ethylene oxide units. In another embodiment of the present claimed invention, the surfactant comprises a nonionic surfactant. In yet another embodiment of the present claimed invention, the surfactant comprises an anionic surfactant. In another embodiment of the present claimed invention, the anionic surfactant comprises at least one alkyl sulfonate, alkyl benzene sulfonate, alkyl sulfate, alkyl benzene sulfate, phosphate, phosphinate, aliphatic carboxylate, or any combination of two or more thereof.

[0086] In yet another embodiment of the presently claimed invention, the surfactant is present in the aqueous composition in an amount of 0% to about 10% by weight, including amounts of 0% to about 9% by weight; 0% to about 8% by weight; 0% to about 7% by weight; 0% to about 6% by weight; 0% to about 5% by weight; 0% to about 4% by weight; 0% to about 3% by weight; 0% to about 2% by weight; 0% to about 1% by weight; about 1% to about 10% by weight; about 1% to about 9% by weight; about 1% to about 8% by weight; about 1% to about 7% by weight; about 1% to about 6% by weight; about 1% to about 5% by weight; about 1% to about 4% by weight; about 1% to about 3% by weight; about 1% to about 2% by weight; about 2% to about 10% by weight; and about 2% to about 9% by weight; about 2% to about 8% by weight; about 2% to about 7% by weight; about 2% to about 6% by weight; about 2% to about 5% by weight; about 2% to about 4% by weight; about 2% to about 3% by weight; about 3% to about 10% by weight; about 3% to about 9% by weight; about 3% to about 8% by weight; about 3% to about 7% by weight; about 3% to about 6% by weight; about 3% to about 5% by weight; about 3% to about 4% by weight; about 5% to about 10% by weight; about 5% to about 9% by weight; about 5% to about 8% by weight; about 5% to about 7% by weight; or about 5% to about 6% by weight. In another embodiment of the presently claimed invention, the surfactant is present in the multi-phase polymer binder in an amount of 0, 1, 2, 3, 4, 5, 6, 7, 8, 9, or 10% by weight (including increments therein). In yet another embodiment of the presently claimed invention, the surfactant is present in the multi-phase polymer binder in an amount of about 1, 2, 3, 4, 5, 6, 7, 8, 9, or 10 wt. % (including increments therein).

[0087] The resin solution may have a solids content of about 15% to about 60% by weight, a pH of 7.0 to 9.5, and a Brookfield viscosity of 35 cps to 6,000 cps, including a solids content of about 30% to about 50% by weight, a pH of 8.0 to 9.0, and a Brookfield viscosity of 100 cps to 1,000 cps.

[0088] The aqueous compositions described herein may contain other materials, such as, but not limited to, additives, pigments, other aqueous resin solutions, rheology modifiers, wetting agents, defoamers, and fillers. Examples of pigments include, but are not limited to, clay, organic pigments, and inorganic pigments. Exemplary other aqueous resin solutions include carboxylic acid-rich copolymers, which may be present at 0% to about 20% by weight or greater than 0% to about 20% by weight. These carboxylic acid-rich copolymers may include copolymers of carboxylic acid-functional monomers, styrene, and (meth)acrylate monomers. For example, the carboxylic acid-rich copolymer may contain 5% to 25% by weight of carboxylic acid-functional monomers, up to about 70% by weight of styrene, and 10% to 90% by weight of (meth)acrylate monomers. Exemplary rheology modifiers include, but are not limited to, hydrophobically modified ethoxylated urethanes, hydrophobically modified polyethers, alkali-swellable emulsions, hydrophobically modified alkali-swellable emulsions, clays, and fumed silica. Rheology modifiers may be used in the formulation at 0% to about 2% by weight, or greater than 0% to about 2% by weight. Exemplary wetting agents include, but are not limited to, alkoxylated surfactants (i.e., difunctional block copolymer surfactants terminated with primary hydroxyl groups or polyethylene glycol and / or propylene glycol), silicone surfactants, sulfosuccinate surfactants, and star-shaped alkoxylated polymers. Wetting agents may be used in the formulation at 0% to about 4% by weight, or greater than 0% to about 4% by weight. Exemplary defoamers include, but are not limited to, oil-based defoamers (i.e., mineral oil, vegetable oil, or white oil), silicon-based defoamers (i.e., polydimethylsiloxanes and their derivatives), aqueous emulsion-based defoamers, aqueous defoamer emulsions based on oils, polymers, and organomodified silicones, polyethylene glycol and / or propylene glycol, and star-shaped polymers. Antifoaming agents may be used in the formulation at 0% to about 0.5% by weight or greater than 0% to about 0.5% by weight. Exemplary fillers include fumed silica, clay materials, i.e., exfoliated or non-exfoliated kaolin, talc, attapulgite, montmorillonite, bentonite, hectorite, etc. and saponite; calcium carbonate, natural mica, and combinations of any two or more thereof. Fillers may be used in the formulation at 0% to about 40% by weight or greater than 0% to about 40% by weight.

[0089] The aqueous compositions described herein, when coated on a substrate and dried, have a density of about 5 g / m 2 / 20 minutes (min) or less. In flexographic coating, the water absorption is about 16 g / m 2 This includes a water absorption of approximately 4.5 g / m 2 / Less than 20 minutes, water absorption capacity approx. 4g / m 2 / Less than 20 minutes, water absorption capacity approx. 3.5g / m 2 / Less than 20 minutes, water absorption capacity approx. 3g / m 2 / Less than 20 minutes, water absorption capacity approx. 2.5g / m 2 / Less than 20 minutes, water absorption capacity approx. 2g / m 2 / Less than 20 minutes, or water absorption of approximately 1g / m 2 In some embodiments, the water absorption is about 1.0, 1.1, 1.2, 1.3, 1.4, 1.5, 1.6, 1.7, 1.8, 1.9, 2.0, 2.1, 2.2, 2.3, 2.4, 2.5, 2.6, 2.7, 2.8, 2.9, 3.0, 3.1, 3.2, 3.3, 3.4, 3.5, 3.6, 3.7, 3.8, 3.9, 4.0, 4.1, 4.2, 4.3, 4.4, 4.5, 4.6, 4.7, 4.8, 4.9, or 5.0 g / m 2 / 20 minutes (including increments therein). In some embodiments, the water absorption is about 0.5 to about 5.0 g / m 2 / 20 minutes. This has a water absorption capacity of approximately 0.5 to 4.5 g / m 2 / 20 minutes, about 0.5~4.0g / m 2 / 20 minutes, about 0.5~3.5g / m 2 / 20 minutes, about 0.5~3.0g / m 2 / 20 minutes, about 0.5~2.5g / m 2 / 20 minutes, about 0.5~2.0g / m 2 / 20 minutes, about 1.0~5.0g / m 2 / 20 minutes, about 1.0~4.5g / m 2 / 20 minutes, about 1.0~4.0g / m2 / 20 minutes, about 1.0~3.5g / m 2 / 20 minutes, about 1.0~3.0g / m 2 / 20 minutes, or about 1.0 to about 2.5 g / m 2 / 20 minutes included.

[0090] One aspect of the presently claimed invention relates to a substrate comprising at least one surface coated with at least one layer comprising the aqueous composition disclosed herein. In one embodiment of the presently claimed invention, the substrate is paper or paperboard.

[0091] The aqueous compositions disclosed herein can be used on any substrate to impart water, moisture, grease, oil, and / or oxygen resistance. In one embodiment of the presently claimed invention, the substrate can be a cellulosic substrate, such as paper, paperboard, or cardboard. Cellulosic substrates may include paper cups, including for example disposable or recycled paper cups, paper bags, for example for dry foods such as coffee, tea, powdered soups, powdered sauces, etc., or for liquids such as cosmetics, cleaning products, beverages, etc.; substrates for tubular laminates; substrates for paper carrier bags; laminated and co-extruded papers for ice cream, confectionery (e.g. chocolate bars and muesli bars); substrates for paper adhesive tapes; substrates for cardboard cups (e.g. paper cups), yogurt pots, soufflé cups; substrates for meal trays or meat trays; substrates for rolled cardboard containers (e.g. cans, drums); substrates for outer wet strength cartons (e.g. wine bottles, food products); substrates for coated cardboard fruit boxes; substrates for fast food plates; substrates for clamp shells; substrates for beverage cartons and cartons for liquids (e.g. detergents and cleaning products), cartons for frozen foods, substrates for ice packaging (e.g. ice cups, packaging material for ice cream cones and wafers); substrates for paper labels; or substrates for flower pots and plant pots.

[0092] Another aspect of the presently claimed invention relates to a coated paper or article comprising the aqueous composition disclosed herein. In one embodiment of the presently claimed invention, the coated paper or article comprising the aqueous composition disclosed herein comprises 1 m of coated paper. 2 In one embodiment of the presently claimed invention, the coated paper or article comprising the aqueous composition disclosed herein has a coating weight in the range of about 2 g to about 30 g per 1 m of coated paper. 2 The coated paper has a coating weight ranging from about 10 g to about 25 g per 1000 kcal. In another embodiment of the presently claimed invention, the coated paper exhibits a blocking resistance of 3 or greater as determined according to ASTM WK20008 at 60°C and 60 psi for 24 hours. In another embodiment of the presently claimed invention, the coated paper exhibits a blocking resistance of 4 or greater as determined according to ASTM WK20008 at 60°C and 60 psi for 24 hours. In yet another embodiment of the presently claimed invention, the coated paper exhibits oil and / or grease resistance.

[0093] Another aspect of the presently claimed invention relates to a method of making paper, the method comprising at least the step of contacting cellulose fibers with an aqueous composition disclosed herein. In one embodiment of the presently claimed invention, the step of contacting the cellulose fibers with the aqueous composition comprises coating a paper web comprising the cellulose fibers with an aqueous dispersion comprising the aqueous composition. In another embodiment of the presently claimed invention, the step of contacting the cellulose fibers with the aqueous composition disclosed herein comprises (i) mixing the cellulose fibers with an aqueous dispersion comprising the aqueous composition to form a slurry; and (ii) forming a paper web from the slurry of cellulose fibers and the aqueous composition.

[0094] In another embodiment of the presently claimed invention, the aqueous composition is coated onto a substrate. For example, the aqueous composition may be provided as a coating on a paper web. The aqueous composition may be applied at a rate of 2 g / m 2 or more, for example, 3 g / m 2 More than 4g / m 2More than 5g / m 2 More than 6g / m 2 More than 7g / m 2 More than 8g / m 2 More than 9g / m 2 More than 10g / m 2 More than 11g / m 2 More than 12g / m 2 More than 13g / m 2 More than 14g / m 2 More than 15g / m 2 More than 16g / m 2 More than 17g / m 2 More than 18g / m 2 More than 19g / m 2 More than 20g / m 2 More than 21g / m 2 More than 22g / m 2 More than 23g / m 2 More than 24g / m 2 More than 25g / m 2 More than 26g / m 2 More than 27g / m 2 More than 28g / m 2 or more, or 29 g / m 2 In one embodiment of the presently claimed invention, the aqueous composition may have a coating weight of 30 g / m or more. 2 For example, 29 g / m 2 Below 28g / m 2 Below 27g / m 2 Below, 26g / m 2 Below 25g / m 2 Below 24g / m 2 Below 23g / m 2 Below, 22g / m 2 Below, 21g / m 2 Below 20g / m 2 Below, 19g / m 2 Below 18g / m 2 Below, 17g / m 2 Below 16g / m 2 Below 15g / m 2 Below, 14g / m 2 Below 13g / m 2 Below, 12g / m 2 Below, 11g / m 2 Below 10g / m2 Below, 9g / m 2 Below, 8g / m 2 Below, 7g / m 2 Below 6g / m 2 Below, 5g / m 2 Below, 4g / m 2 Less than or equal to 3g / m 2 In yet another embodiment of the presently claimed invention, the aqueous composition may have a coating weight of 2 g / m 2 ~30g / m 2 , e.g., 3 g / m 2 ~30g / m 2 , 4g / m 2 ~30g / m 2 , 5g / m 2 ~30g / m 2 , or 10 g / m 2 ~25g / m 2 The coating weight can be reported in units of grams of coating per square meter of cellulosic substrate and can be calculated directly from the amount of coating applied and the surface area of ​​the cellulosic substrate to which the coating is applied. In one embodiment of the presently claimed invention, the aqueous composition can be applied in an amount less than 15% by weight, based on the weight of the coated cellulosic substrate. In some embodiments, the aqueous composition can be present in an amount of 0.01% to 5%, e.g., 0.1% to 5%, 0.5% to 5%, 0.1% to 4%, 0.1% to 3%, 0.1% to 2.5%, or 0.1% or more, 0.5% or more, 1% or more, 1.5% or more, by weight of the substrate.

[0095] In one embodiment of the claimed invention, the aqueous composition can have a thickness of 0.40 mils or more, e.g., 0.5 mils or more, 0.6 mils or more, 0.7 mils or more, 0.8 mils or more, 0.9 mils or more, 1 mil or more, 1.1 mils or more, 1.2 mils or more, 1.3 mils or more, 1.4 mils or more, 1.5 mils or more, 1.6 mils or more, 1.7 mils or more, 1.8 mils or more, or 1.9 mils or more. In one embodiment of the claimed invention, the aqueous composition can have a thickness of 2 mils or less, e.g., 1.9 mils or less, 1.8 mils or less, 1.7 mils or less, 1.6 mils or less, 1.5 mils or less, 1.4 mils or less, 1.3 mils or less, 1.2 mils or less, 1 mil or less, 0.9 mils or less, 0.8 mils or less, 0.7 mils or less, 0.6 mils or less, or 0.5 mils or less. In some embodiments, the aqueous composition can have a thickness of 0.4 mil to 2 mil, e.g., 0.5 mil to less than 1.8 mil, 0.6 mil to 1.6 mil, or 0.7 mil to 1.5 mil. The coating thickness can be calculated based on the density of the coating and the mass of the coated cellulosic substrate.

[0096] In one embodiment of the claimed invention, the coating comprises an aqueous composition. In another embodiment of the claimed invention, the coating can be present on one or more surfaces of a substrate. In the context of the claimed invention, the substrate can also refer to a paper cup or a paper bag. The paper cup can have an inner surface, an outer surface, a bottom, and sides. The aqueous composition can be present on a first surface and / or a second surface of the paper cup. The first surface can include one or more of the inner surfaces of the sides and / or the inner surface of the bottom. In some embodiments, only a portion of the inner surface is coated, for example, 10% or more, 20% or more, 30% or more, 40% or more, 50% or more, 60% or more, 70% or more, 80% or more, 90% or more, or the entire inner surface. In one embodiment of the claimed invention, the entire inner surface is coated. In one embodiment of the claimed invention, the second surface includes one or more of the outer surfaces of the sides and / or the outer surface of the bottom. In other embodiments of the presently claimed invention, only a portion of the exterior surface is coated, for example, 10% or more, 20% or more, 30% or more, 40% or more, 50% or more, 60% or more, 70% or more, 80% or more, 90% or more, or the entire exterior surface is coated. In yet other embodiments of the presently claimed invention, the entire exterior surface is coated.

[0097] The aqueous composition can be coated onto the cellulosic substrate using a paper mill machine or by a printing process.

[0098] In one embodiment of the claimed invention, the aqueous composition is provided throughout a substrate, such as a paper web formed of cellulose fibers. In yet another embodiment of the claimed invention, the aqueous composition can be present in an amount of 4% to 30% by weight of the substrate, such as 5% to 30%, 5% to 29%, 5% to 28%, 5% to 27%, 5% to 26%, 5% to 20%, or 4% or more, 5% or more, 6% or more, 7% or more, 8% or more, 9% or more, or 10% or more by weight, all based on the weight of the substrate.

[0099] The aqueous composition can be applied to a substrate, such as a cellulosic substrate, using any method known in the art for applying an aqueous composition to a substrate. In one embodiment of the claimed invention, the method can include coating a paper web including cellulose fibers with an aqueous dispersion including the aqueous composition. In another embodiment of the claimed invention, the method can include spraying the aqueous dispersion including the aqueous composition onto the paper web. In yet another embodiment of the claimed invention, the method can include mixing the aqueous dispersion including the aqueous composition with a slurry including cellulose fibers to form a mixture, and forming a paper web from the mixture of cellulose fibers and the aqueous composition.

[0100] In one embodiment of the claimed invention, the aqueous composition may impart water, moisture, grease, oil, and / or oxygen resistance to a substrate compared to an application that does not include the aqueous composition. The substrate may also exhibit reduced or absent bleeding or coloration. The resistance of a substrate containing the aqueous composition to liquid water and water vapor can be tested by the Cobb method described in TAPPI T 441 (2001), which is incorporated herein by reference in its entirety. This method determines the amount of liquid water or water vapor absorbed by paper, paperboard, and corrugated board under standard conditions in a specified time. In one embodiment of the claimed invention, the coated substrate described herein will pass the water resistance test described in this test method. Water absorption can be a function of various properties of the paper or paperboard, including, but not limited to, sizing and porosity.

[0101] In one embodiment of the presently claimed invention, the substrate containing the aqueous composition has a concentration of about 0.01 g / m at 20 minutes. 2 25g / m at ~20 minutes 2 , e.g., 25 g / m 2 Below 20g / m 2 Below 15g / m 2 Below 10g / m 2 or less than 5g / m 2The substrate containing the aqueous composition may exhibit the following Cobb values: a 24-hour moisture vapor transmission rate (MVTR) of 35 g / m when measured at 25°C and 50% RH; 2 For example, a substrate containing an aqueous composition may exhibit a water vapor transmission rate of 32 g / m 2 Below 30g / m 2 Below 27g / m 2 Below 25g / m 2 Below, 22g / m 2 Below 20g / m 2 Below 18g / m 2 Below, 17g / m 2 or less than 15g / m 2 In yet another embodiment of the presently claimed invention, the substrate comprising the aqueous composition may exhibit a water vapor transmission rate of 5 g / m 2 or more than 10g / m 2 The above can be shown.

[0102] Furthermore, substrates containing the aqueous compositions described herein may exhibit minimal blocking tendencies, i.e., adhesion of a coated surface to another coated surface, or adhesion of a coated surface to the uncoated surface of an extrusion-coated paper, when wound into a paper roll before being cut / formed into a finished paper product. Blocking resistance can be tested using an IC blocking tester as described in ASTM WK20008. Samples may be given a rating of 1 to 5 based on the following scale: 1—very low tack, 2—low tack, 3—high tack, 4—stickiness, approximately 25% fiber tear, and 5—greater than 25% fiber tear. For the purposes of the claimed invention, sufficient blocking resistance refers to a rating of 5 according to the grading system described in this example. For the purposes of the claimed invention, the presence of substrate damage is assessed visually. For the purposes of the claimed invention, "no substrate damage" refers to no visually observable substrate damage.

[0103] All publications, patent applications, issued patents, and other documents referenced herein are incorporated by reference herein to the same extent as if each individual publication, patent application, issued patent, or other document was specifically and individually indicated to be incorporated by reference in its entirety. Definitions contained in documents incorporated by reference are excluded to the extent they conflict with definitions in this disclosure.

[0104] Embodiment Below, a list of embodiments is presented to further illustrate the present disclosure, but is not intended to limit the disclosure to the specific embodiments listed below.

[0105] Embodiment 1 (i) at least one first polymer in an amount ranging from about 10% to about 90% by weight derived from at least one first monomer selected from an ethylenically substituted aromatic compound and at least one second monomer selected from the group consisting of (meth)acrylonitrile, (meth)acrylamide, (meth)acrylic acid, alkyl (meth)acrylate, and mixtures thereof; and (ii) at least one second polymer in an amount ranging from about 10% to about 90% by weight, comprising the reaction product of a partially neutralized acid-functional support resin with at least one ethylenically unsaturated monomer selected from the group consisting of olefins, monovinylidene aromatic compounds, α,β-ethylenically unsaturated carboxylic acids and esters thereof, ethylenically unsaturated dicarboxylic acid anhydrides, and mixtures thereof; Including, Aqueous composition, where all weight percentages are based on the total weight of the aqueous composition.

[0106] Embodiment 2 2. The aqueous composition of embodiment 1, wherein the ratio of the volume average particle size of the at least one first polymer to the volume average particle size of the at least one second polymer ranges from about 20:1 to about 2:1.

[0107] Embodiment 3 2. The aqueous composition of embodiment 1, wherein the viscosity of the aqueous composition, measured at 23° C. using a viscometer equipped with a No. 2 spindle at 50 rpm, ranges from about 100 cP to about 2500 cP.

[0108] Embodiment 4 2. The aqueous composition of embodiment 1, wherein the solids content of the aqueous composition is in the range of about 20% to about 70% by weight, based on the total weight of the aqueous composition.

[0109] Embodiment 5 2. The aqueous composition of embodiment 1, wherein the weight average molecular weight of the first polymer, as determined according to gel permeation chromatography, ranges from about 20 kDa to about 500 kDa.

[0110] Embodiment 6 2. The aqueous composition of embodiment 1, wherein the volume average particle size of the first polymer is in the range of about 90 nm to about 400 nm as determined by dynamic light scattering techniques.

[0111] Embodiment 7 2. The aqueous composition of embodiment 1, wherein the viscosity of the first polymer ranges from about 100 cP to about 2500 cP, as measured at 23° C. using a viscometer equipped with a No. 2 spindle at 50 rpm.

[0112] Embodiment 8 10. The aqueous composition of embodiment 1, wherein the at least one first monomer is different from the at least one second monomer.

[0113] Embodiment 9 9. The aqueous composition of embodiment 8, wherein the ethylenically substituted aromatic compound is selected from the group consisting of styrene, methylstyrene, butylstyrene, decylstyrene, vinyltoluene, indene, methylindene, and mixtures thereof.

[0114] Embodiment 10 10. The aqueous composition of any one of embodiments 1 to 9, wherein the amount of the first monomer is in the range of about 10% to about 50% by weight and the amount of the second monomer is in the range of about 10% to about 90% by weight, both relative to the total weight of the first polymer.

[0115] Embodiment 11 11. The aqueous composition of any one of embodiments 1 to 10, wherein the amount of the first monomer in the first polymer is in the range of about 10% to about 40% by weight, and the amount of the second monomer in the first polymer is in the range of about 20% to about 90% by weight, both relative to the total weight of the first polymer.

[0116] Embodiment 12 12. The aqueous composition of any one of embodiments 1 to 11, wherein the amount of the at least one first monomer in the first polymer is in the range of about 10% to about 30% by weight, and the amount of the at least one second monomer in the first polymer is in the range of about 70% to about 90% by weight, both relative to the total weight of the first polymer.

[0117] Embodiment 13 2. The aqueous composition of embodiment 1, wherein the second polymeric partially neutralized acid-functional support resin is selected from the group consisting of ammonium salts of modified acrylic copolymers, amine salts of modified acrylic copolymers, and mixtures thereof.

[0118] Embodiment 14 14. The aqueous composition of embodiment 13, wherein the modified acrylic copolymer is derived from the group consisting of (meth)acrylic acid monomers, (meth)acrylate monomers, vinyl aromatic monomers, and mixtures thereof.

[0119] Embodiment 15 The weight average molecular weight of the second polymer, as determined according to gel permeation chromatography, ranges from about 100 kDa to about 1000 kDa.

[0120] Embodiment 16 2. The aqueous composition of embodiment 1, wherein the volume average particle size of the second polymer is in the range of about 50 nm to about 200 nm as determined by light scattering techniques.

[0121] Embodiment 17 2. The aqueous composition of embodiment 1, wherein the viscosity of the second polymer is in the range of about 1000 cP to about 5000 cP, measured at 23° C. using a viscometer equipped with a No. 2 spindle at 50 rpm.

[0122] Embodiment 18 2. The aqueous composition of embodiment 1, wherein the weight average molecular weight of the partially neutralized acid-functional support resin, as determined according to gel permeation chromatography, ranges from about 2 kDa to about 20 kDa.

[0123] Embodiment 19 2. The aqueous composition of embodiment 1, wherein the partially neutralized acid-functional support resin is neutralized with a base selected from the group consisting of ammonia, sodium hydroxide, potassium hydroxide, organic amines, and mixtures thereof.

[0124] Embodiment 20 2. The aqueous composition of embodiment 1, wherein partial neutralization means neutralization of at least about 5 mol % of the acid groups on the acid-functional support resin with a base.

[0125] Embodiment 21 21. The aqueous composition of any one of the preceding embodiments, wherein the second polymer comprises the partially neutralized acid-functional support resin in an amount of from about 10% to about 50% by weight, and the at least one ethylenically unsaturated monomer in an amount ranging from about 5% to about 90% by weight, both based on the total weight of the second polymer.

[0126] Embodiment 22 22. The aqueous composition of any one of the preceding embodiments, wherein the second polymer comprises the partially neutralized acid-functional support resin in an amount of from about 10% to about 40% by weight, and the at least one ethylenically unsaturated monomer in an amount ranging from about 20% to about 90% by weight, both based on the total weight of the second polymer.

[0127] Embodiment 23 23. The aqueous composition of any one of the preceding embodiments, wherein the second polymer comprises the partially neutralized acid-functional support resin in an amount of from about 10% to about 30% by weight, and the at least one ethylenically unsaturated monomer in an amount ranging from about 70% to about 90% by weight, both based on the total weight of the second polymer.

[0128] Embodiment 24 10. The aqueous composition of embodiment 1, further comprising a wax in an amount ranging from about 0.10% to about 25% by weight, based on the total weight of the aqueous composition.

[0129] Embodiment 25 25. The aqueous composition of embodiment 24, wherein the wax is an aqueous emulsion.

[0130] Embodiment 26 26. The aqueous composition of embodiment 25, wherein the aqueous emulsion is selected from the group consisting of paraffin, polyethylene, polypropylene, microcrystalline wax, fluorinated wax, ethylene copolymer wax, propylene copolymer wax, and mixtures thereof.

[0131] Embodiment 27 27. The aqueous composition of any one of the preceding embodiments, further comprising a surfactant.

[0132] Embodiment 28 28. The aqueous composition of embodiment 27, wherein the surfactant is anionic or nonionic.

[0133] Embodiment 29 29. The aqueous composition of embodiment 28, wherein the surfactant is selected from the group consisting of alkyl sulfonates, alkyl benzene sulfonates, alkyl sulfates, alkyl benzene sulfates, phosphates, phosphinates, aliphatic carboxylates, and mixtures thereof.

[0134] Embodiment 30 29. The aqueous composition of embodiment 28, wherein the surfactant comprises at least one fatty alcohol ethoxylate.

[0135] Embodiment 31 29. The aqueous composition of embodiment 28, wherein the surfactant comprises at least one alkyl sulfosuccinate ethoxylate.

[0136] Embodiment 32 29. The aqueous composition of embodiment 28, wherein the surfactant comprises at least one alkyl sulfosuccinate ethoxylate and at least one fatty alcohol ethoxylate.

[0137] Embodiment 33 29. The aqueous composition of embodiment 28, wherein the surfactant comprises at least one fatty alcohol having an alkyl chain length of from about 12 carbons to about 18 carbons and a degree of ethoxylation of from about 10 moles of ethylene oxide units to about 80 moles of ethylene oxide units.

[0138] Embodiment 34 33. A substrate comprising at least one surface coated with at least one layer comprising the aqueous composition of any one of embodiments 1 to 32.

[0139] Embodiment 35 35. The substrate of embodiment 34, which is paper or paperboard.

[0140] Embodiment 36 34. A coated paper or article comprising the aqueous composition of any one of embodiments 1 to 33.

[0141] Embodiment 37 The aqueous composition is applied to 1 m of coated paper. 2 37. The coated paper or article of embodiment 36, comprising a coating weight in the range of about 2 g to about 30 g per coated paper or article.

[0142] Embodiment 38 38. The coated paper of embodiment 37, which exhibits a blocking resistance of 3 or greater as determined according to ASTM WK20008 at 60° C. and 60 psi for 24 hours.

[0143] Embodiment 39 37. Coated paper, as defined in embodiment 36, exhibiting oil and / or grease resistance.

[0144] Embodiment 40 34. A method for making paper, comprising at least the step of contacting cellulose fibers with the aqueous composition of any one of embodiments 1 to 33.

[0145] Embodiment 41 41. The method of embodiment 40, wherein the step of contacting the cellulose fibers with the aqueous composition comprises coating a paper web comprising cellulose fibers with an aqueous dispersion comprising the aqueous composition.

[0146] Embodiment 42 41. The method of embodiment 40, wherein the step of contacting the cellulose fibers with the aqueous composition comprises: (i) mixing the cellulose fibers with an aqueous dispersion comprising the aqueous composition to form a slurry; and (ii) forming a paper web from the slurry of the cellulose fibers and the aqueous composition.

[0147] While the claimed invention has been described in terms of specific embodiments thereof, certain modifications and equivalents will be apparent to those skilled in the art and are intended to be included within the scope of the claimed invention.

[0148] The claimed invention has at least one of the following advantages: i) The presently claimed invention imparts good barrier and blocking resistance to paper or paperboard substrates coated with the compositions disclosed herein. ii) The presently claimed invention provides improved oil and grease resistance to paper or paperboard substrates coated with the compositions disclosed herein. iii) The presently claimed invention provides grease resistance at temperatures from about room temperature to about 60°C to paper or paperboard substrates coated with the compositions disclosed herein. iv) The presently claimed invention imparts improved temperature crease and fold grease resistance to paper or paperboard substrates coated with the compositions disclosed herein. v) Paper or paperboard substrates coated with the compositions of the presently claimed invention are repulpable and recyclable. vi) The claimed invention provides better packaging during film formation by improving grease resistance while maintaining blocking resistance. vii) The aqueous compositions of the presently claimed invention achieve the high solids content at the low viscosity required for printing, thereby facilitating printing. [Example]

[0149] Aspects of the presently claimed invention are more fully described by the following examples, which are presented to illustrate certain aspects of the invention and should not be construed as limiting the invention.

[0150] component The abbreviations for the monomers used in the aqueous composition are as follows: AA is the abbreviation for acrylic acid obtained from Aldrich Chemical Company BA is the abbreviation for butyl acrylate obtained from Aldrich Chemical Company MAA is the abbreviation for methacrylic acid obtained from Aldrich Chemical Company MMA is the abbreviation for methyl methacrylate, obtained from Aldrich Chemical Company AMS is α-methylstyrene obtained from Aldrich Chemical Company; 2-EHA is the abbreviation for 2-ethylhexyl acrylate, obtained from Aldrich Chemical Company; HEA is an abbreviation for hydroxyethyl acrylate obtained from Aldrich Chemical Company STY is an abbreviation for styrene obtained from Aldrich Chemical Company APS is an abbreviation for ammonium persulfate, obtained from Aldrich Chemical Company. tBHP is an abbreviation for tert-butyl hydroperoxide, obtained from Aldrich Chemical Company. Joncryl® Wax 28 is a paraffin / polyethylene wax emulsion obtained from BASF. FoamStar® SI 2240 is a broad-spectrum silicone antifoam compound obtained from BASF. Sterocoll® FS is a thickener based on an aqueous dispersion of an acrylic copolymer, obtained from BASF.

[0151] Example 1A The second polymer was synthesized by a continuous high-temperature polymerization process. Configure Preparation of polymer resins and aqueous resin dispersions Polymers suitable for use in the present invention can be prepared by addition polymerization in homogeneous or heterogeneous media. Thus, conventional techniques such as bulk polymerization, solution polymerization, emulsion polymerization, etc. can be used to produce suitable polymers of the present invention.

[0152] Table 1 summarizes the compositions of the polymers used in this invention. These polymers were made by a continuous free radical polymerization process at relatively high temperatures, where the polymerization is carried out in a homogeneous environment. The high reaction temperature allows low molecular weights to be achieved without the use of chain transfer agents. After the polymerization step, the resin is subjected to a devolatilizer to remove unreacted monomers and process solvents. It should be noted that the polymers shown in Table 1 were prepared by the high-temperature continuous polymerization process described in U.S. Pat. Nos. 5,461,60; 4,414,370; and 4,529,787, all of which are incorporated herein by reference.

[0153] [Table 1]

[0154] Example 1B The second polymer Configure Synthesis of aqueous resin dispersion The acid-functional polymers listed in Table 1 were dispersed in water by neutralizing some of their acid groups with a base under stirring and heating. For example, a 28.5 wt. % solids dispersion of P3 was prepared by adding 220 grams of P3, 473.7 grams of deionized water, and 50.3 grams of ammonia (29 wt. % active) to a reaction vessel equipped with a condenser and an overhead stirrer. The mixture was heated to 88-92°C under stirring and held for 4 hours, then cooled to room temperature and filtered to obtain PD3.

[0155] Table 2 describes the polymer dispersions prepared in this manner. Dispersions containing two or more acid-functional polymers can be made by this method, starting with a mixture of the polymers. In this way, particles containing both starting resins are formed.

[0156] [Table 2]

[0157] Example 2 Second Polymer Configure Partially Neutralized Acid Functional Support Resin and Synthesis of rheology-controlled acrylic emulsion polymers Deionized water (31.1 grams) and the resin support dispersion from Example 1B (PD3, 93.4 grams, 28.5% solids) were added to a reaction vessel equipped with a condenser, thermometer, nitrogen inlet, and overhead stirrer and heated to 82°C under a nitrogen flow. Ammonium persulfate (0.66 grams) and deionized water (51.2 grams) were added and held with stirring for 3 minutes. A monomer mixture (17 grams of methyl methacrylate, 38.8 grams of butyl acrylate, and 24.9 grams of 2-ethylhexyl acrylate) was added over 90 minutes, followed by a 1.3 gram deionized water flush and a 30 minute hold. tert-Butyl hydroperoxide (0.4 grams) and deionized water (2.38 grams) were added and held for 10 minutes. Sodium erythorbate (1.4 grams) and deionized water (3.2 grams) were added over 15 minutes and held for 10 minutes. The reaction was cooled to room temperature and filtered. The desired resin-reinforced emulsion polymer is obtained having the following properties: viscosity of 1800 cps at 25°C measured with a Brookfield LV, No. 3 spindle at 30 rpm for 30 seconds; solids content of 48% by weight; Tg = -27°C; MFFT = 5°C or less; acid number = 64 mg KOH / gram; particle size (volume mean diameter, dv) = 81 nm; and Mw = 826 kDa.

[0158] Example 3 First Polymer Configure Dispersion synthesis Deionized water (217.9 grams), polystyrene (7.6 grams, Aldrich Chemical Co.), and DSI (14.53 grams) were added to a reaction vessel equipped with a condenser, thermometer, nitrogen inlet, and overhead stirrer and heated to 90°C under a nitrogen stream. Sodium persulfate (6.9 grams, Aldrich Chemical Co.) was added and held with stirring for 3 minutes. A monomer mixture (acrylic acid, Aldrich Chemical Co., 14.2 grams; acrylonitrile, Aldrich Chemical Co., 68.54 grams; n-butyl acrylate, Aldrich Chemical Co., 338.8 grams; and styrene, Aldrich Chemical Co., 68.54 grams) was added over 180 minutes, while sodium persulfate (42.1 grams) and a mixture (TSPP 45 grams, Disponil SDS 15 7.83 grams, and deionized water 121.7 grams) were added over 240 minutes. At the end of the feeds, tert-butyl hydroperoxide (10.77 grams) and sodium metabisulfite (10.77 grams) were added and held for 10 minutes. After distillation of residual unreacted monomer, the reaction was cooled to room temperature and filtered. The desired aqueous acrylic dispersion polymer was obtained, having the following properties: viscosity of 534 cps at 23°C measured with a Brookfield RV, No. 2 spindle at 20 rpm; solids content of 50% by weight; Tg = -8°C; MFFT = -2°C or less; particle size (volume average diameter, dv) = 170 nm; and Mw = 122 kDa.

[0159] Example 4 Packaging Coating Compounds A coating composition was prepared by sequentially adding, with stirring, Example 2 (71.82 grams), Resin Dispersion PD2 (15.66 grams), Joncryl Wax 28 (5.15 grams), FoamStar SI 2240 (0.10 grams), and deionized water (7.27 grams). The formulation was stirred at room temperature for 20 minutes. The aqueous formulation had a resulting viscosity of 150 cps (Brookfield RV, No. 2 spindle, 30 rpm, 23°C) and a solids content of 41.3% by weight.

[0160] Example 5 Packaging Coating Compounds A coating composition was prepared by sequentially adding, with stirring, Example 2 (55.35 grams), Example 3 (18.48 grams), Resin Dispersion PD2 (16.10 grams), Joncryl Wax 28 (5.30 grams), FoamStar SI 2240 (0.10 grams), and deionized water (4.67 grams). The formulation was stirred at room temperature for 20 minutes. The aqueous formulation had a resulting viscosity of 131 cps (Brookfield RV, No. 2 spindle, 30 rpm, 23°C) and a solids content of 42.9% by weight.

[0161] Example 6 Packaging Coating Compounds A coating composition was prepared by sequentially adding, with stirring, Example 2 (38.61 grams), Example 3 (38.61 grams), Resin Dispersion PD2 (16.81 grams), Joncryl Wax 28 (5.53 grams), FoamStar SI 2240 (0.11 grams), and deionized water (0.33 grams). The formulation was stirred at room temperature for 20 minutes. The aqueous formulation had a resulting viscosity of 152 cps (Brookfield RV, No. 2 spindle, 30 rpm, 23°C) and a solids content of 45.6% by weight.

[0162] Example 7 Packaging Coating Compounds A coating composition was prepared by sequentially adding, with stirring, Example 3 (74.65 grams), Resin Dispersion PD2 (16.27 grams), Joncryl Wax 28 (5.35 grams), FoamStar SI 2240 (0.11 grams), Sterocoll FS (0.47 grams), and deionized water (3.15 grams). The formulation was stirred at room temperature for 20 minutes. The aqueous formulation had a resulting viscosity of 155 cps (Brookfield RV, No. 2 spindle, 30 rpm, 23°C) and a solids content of 46.1% by weight.

[0163] Example 8 Packaging Coating Compounds A coating composition was prepared by sequentially adding Example 2 (60 grams), Example 3 (40 grams), and deionized water (1.45 grams) with stirring. The mixture was stirred at room temperature for 20 minutes. The aqueous mixture had a resulting viscosity of 124 cps (Brookfield RV, No. 2 spindle, 30 rpm, 23°C) and a solids content of 47.9% by weight.

[0164] Example 9 Packaging Coating Compounds A coating composition was prepared by sequentially adding Example 2 (50 grams) and Example 3 (50 grams) with stirring. The formulation was stirred at room temperature for 20 minutes. The aqueous formulation had a resulting viscosity of 126 cps (Brookfield RV, No. 2 spindle, 30 rpm, 23°C) and a solids content of 50.03% by weight.

[0165] Example 10 Packaging Coating Compounds A coating composition was prepared by sequentially adding Example 2 (40 grams) and Example 3 (60 grams) with stirring. The formulation was stirred at room temperature for 20 minutes. The aqueous formulation had a resulting viscosity of 109 cps (Brookfield RV, No. 2 spindle, 30 rpm, 23°C) and a solids content of 48.96% by weight.

[0166] Example 11 Measuring the blocking resistance of coated substrates Coating Application A uniform flexographic coating was applied to the substrate at the specified coating weight using a Pamarco automatic proofer. Each coating layer was dried in an oven at 60°C for 1 minute.

[0167] Unless otherwise indicated, coatings were applied using two passes through a 120* LPI (22.6 BCM) or 140† LPI (17.9 BCM) hand proofer using the same polymer resin. Coating weight was determined at a theoretical 25% transfer.

[0168] Blocking resistance Blocking resistance tests were conducted to determine the resistance of polymeric binders to adhesion to themselves and uncoated paper under pressure and elevated temperatures. The tests measure the degree of sticking and damage experienced by coated substrates when subjected to standard temperature, pressure, and time. Depending on the paper's uniformity, rolls of coated stock can experience internal pressures of up to 60 psi. When stored or transported under tropical conditions (30°C and 95% relative humidity), coated paper layers can adhere to each other, and in a worst-case scenario, the paper or coating can be significantly damaged. Blocking resistance tests were conducted at 50°C and 60 psi for 24 hours. Samples were cut into 1 x 3 inch pieces, and two sheets were laminated in a blocking test apparatus, coated-to-paper (face-to-back, FB) or coated-to-coated (face-to-face, FF) configuration. A spring was then attached to the layers to apply a fixed amount of pressure to the sample. The entire apparatus was placed in a humid oven at 50°C for 24 hours. A Koehler Instrument K53000 IC Blocking Tester was used for this test. Upon completion of the blocking test, the samples were removed and monitored for sticking and damage to the samples. The rating system is listed in Table 3. Blocking resistance data is shown in Table 4.

[0169] [Table 3]

[0170] [Table 4]

[0171] Example 12 Measuring the oil and grease resistance of coating substrates Starting with the coated paper samples prepared in Example 11, three replicates of each sample were cut, and the samples were tested flat and with a crease. When the samples were cut, three samples were creased using a carton crease proofer. The samples were placed coated-side down on the proofer and then folded inward. One gram of a 2% by weight Sudan Blue / oleic acid mixture was applied to a folded paper towel and placed in the center of a flat glass panel. The coated side of the coated test sample was placed on a piece of paper towel soaked with oil. Another glass plate was placed on top of the test sample. After 1 hour, 5 hours, and 24 hours, the samples were evaluated to determine whether they experienced a failure mode, as determined by leaching of blue dye through the test coating.

[0172] [Table 5]

[0173] [Table 6]

[0174] Discussion of results The results in Tables 4, 5, and 6, and Examples 1 through 10, demonstrate that the aqueous compositions of the presently claimed invention impart blocking resistance and improved oil and grease resistance to substrates coated with the aqueous compositions disclosed herein. Surprisingly, it was found that blocking resistance was still achieved when the glass transition temperatures, Tg, of both the first and second polymers in the composition were below 0°C. Tables 5 and 6 show the percent coating area rating for each time frame, which correlates to the penetration of oil and grease through the coating. The results recorded in these tables demonstrate that the aqueous compositions of the presently claimed invention exhibit excellent crease grease resistance, expressed as percent area. The lower the value per area, the better the resistance. The improved properties of the coated substrate result from the synergistic effects of the components of the composition, particularly the first and second polymers in the aqueous compositions disclosed herein. The second polymer, when used alone, provides grease resistance at room temperature but not at elevated temperatures, whereas the aqueous composition disclosed herein provides good grease resistance at both room temperature and elevated temperatures, e.g., 60°C.

[0175] The ratio of the volume average particle sizes of the first polymer and the second polymer in the aqueous composition allows for better packing during film formation, improving grease resistance from the first polymer while maintaining blocking resistance from the second polymer. Furthermore, Examples 1 through 10 demonstrate that the aqueous compositions disclosed herein enable the high solids content at low viscosity required to facilitate paper printing. Surprisingly, the viscosity of the final aqueous composition was much lower than that of the first and second polymers separately. The unique compositions disclosed herein also improve coating transfer along with water resistance. The second polymer, when used alone, provides good water resistance when coated with a wire-wound rod, but does not provide sufficient transfer for building up coating mass by flexographic printing.

[0176] Test Method Determination of molecular weight Gel permeation chromatography (GPC) spectra were obtained on a Waters 2695 instrument and used to determine the molecular weight of the polymers. Tetrahydrofuran (THF) was used as the mobile phase at 40°C, and an RI detector was used. All samples were analyzed for number average molecular weight (Mn), weight average molecular weight (Mw), and polydispersity index (PDI) using elution times calibrated against polystyrene molecular weight standards.

[0177] The number average molecular weight (Mn) is the statistical average molecular weight of all polymer chains in a polymer and is determined by the following formula: M n =(ΣN i M i ) / ΣN i where Mi is the molecular weight of the chain and Ni is the number of chains in that molecular weight.

[0178] The weight average molecular weight (Mw) is determined by the following formula: M w =(ΣNiMi 2 ) / ΣNi

[0179] Compared to Mn, Mw takes into account the molecular weight of the chain in determining its contribution to the molecular weight average: the larger the chain, the greater its contribution to Mw.

[0180] The relatively high average molecular weight (Mz) can be determined by the following formula: M z =(ΣNiMi 3 ) / ΣNi

[0181] The dispersity index or polydispersity index (PDI) is a measure of the distribution of molecular weights in a given polymer sample. The PDI of a polymer is calculated by the following formula: PDI=Mw / Mn In the formula, the weight average molecular weight and the statistical average molecular weight are as defined above.

[0182] Determining the solids content The solids content of the dispersion was determined gravimetrically by drying about 0.5 g to about 2 g of a sample of the dispersion in a 140° C. oven for 1 hour.

[0183] Determining viscosity Viscosity was measured by Brookfield LV at 20℃-25℃.

[0184] Determination of particle size, including volume average particle size The particle size of the dispersion was measured using a Microtrac nano-flex particle size analyzer.

[0185] Determining the acid value Acid number was determined by potentiometric titration according to ASTM D664-95.

[0186] Determination of glass transition temperature The glass transition temperature (Tg) was measured by differential scanning calorimetry (DSC) according to ASTM D3418-15.

[0187] Determining the minimum film forming temperature (MFFT) MFFT was measured according to ASTM D2354-10.

Claims

1. (i) at least one first polymer in an amount ranging from 10% to 90% by weight derived from at least one first monomer selected from an ethylenically substituted aromatic compound and at least one second monomer selected from the group consisting of (meth)acrylonitrile, (meth)acrylamide, (meth)acrylic acid, alkyl (meth)acrylate, and mixtures thereof; and (ii) at least one second polymer in an amount ranging from 10% to 90% by weight, comprising the reaction product of a partially neutralized acid-functional support resin with at least one ethylenically unsaturated monomer selected from the group consisting of olefins, monovinylidene aromatic compounds, α,β-ethylenically unsaturated carboxylic acids and esters thereof, ethylenically unsaturated dicarboxylic acid anhydrides, and mixtures thereof; Including, All weight percentages are based on the total weight of the aqueous composition; An aqueous composition, wherein the ratio of the volume average particle size of the at least one first polymer to the volume average particle size of the at least one second polymer is in the range of 20:1 to 2:

1.

2. 10. The aqueous composition of claim 1, wherein the viscosity of the aqueous composition, as determined at 23°C using a viscometer equipped with a No. 2 spindle at 50 rpm, ranges from 100 cp to 2500 cp.

3. The aqueous composition described in claim 1, wherein the solids content of the aqueous composition, determined gravimetrically by drying a 0.5 g to 2 g sample of the aqueous composition in an oven at 140°C for 1 hour, is in the range of 20% to 70% by weight based on the total weight of the aqueous composition.

4. 10. The aqueous composition of claim 1, wherein the weight average molecular weight of the first polymer is in the range of 20 kDa to 500 kDa as determined according to gel permeation chromatography.

5. 10. The aqueous composition of claim 1, wherein the volume average particle size of the first polymer is in the range of 90 nm to 400 nm as determined according to dynamic light scattering techniques.

6. 10. The aqueous composition of claim 1, wherein the viscosity of the first polymer is in the range of 100 cp to 2500 cp as determined at 23°C using a viscometer equipped with a No. 2 spindle at 50 rpm.

7. The aqueous composition of claim 1 , wherein the at least one first monomer is different from the at least one second monomer.

8. 8. The aqueous composition of claim 7, wherein the ethylenically substituted aromatic compound is selected from the group consisting of styrene, methylstyrene, butylstyrene, decylstyrene, vinyltoluene, indene, methylindene, and mixtures thereof.

9. 9. The aqueous composition according to any one of claims 1 to 8, wherein the amount of the first monomer is in the range of 10% to 50% by weight and the amount of the second monomer is in the range of 10% to 90% by weight, both relative to the total weight of the first polymer.

10. 10. The aqueous composition of claim 1, wherein the amount of the first monomer is in the range of 10% to 40% by weight and the amount of the second monomer is in the range of 20% to 90% by weight, both relative to the total weight of the first polymer.

11. 11. The aqueous composition according to any one of claims 1 to 10, wherein the amount of the at least one first monomer is in the range of 10% to 30% by weight and the amount of the at least one second monomer is in the range of 70% to 90% by weight, both relative to the total weight of the first polymer.

12. 10. The aqueous composition of claim 1, wherein the partially neutralized acid-functional support resin is selected from the group consisting of ammonium salts of modified acrylic copolymers, amine salts of modified acrylic copolymers, and mixtures thereof.

13. 13. The aqueous composition of claim 12, wherein the modified acrylic copolymer is derived from the group consisting of (meth)acrylic acid monomers, (meth)acrylate monomers, vinyl aromatic monomers, and mixtures thereof.

14. 10. The aqueous composition of claim 1, wherein the weight average molecular weight of the second polymer, as determined according to gel permeation chromatography, is in the range of 100 kDa to 1000 kDa.

15. 10. The aqueous composition of claim 1, wherein the volume average particle size of the second polymer is in the range of 50 nm to 200 nm as determined according to dynamic light scattering techniques.

16. 10. The aqueous composition of claim 1, wherein the viscosity of the second polymer is in the range of 100 cp to 5000 cp as determined at 20°C using a viscometer equipped with a No. 2 spindle at 50 rpm.

17. 10. The aqueous composition of claim 1, wherein the weight average molecular weight of the partially neutralized acid-functional support resin, as determined according to gel permeation chromatography, is in the range of 2 kDa to 20 kDa.

18. 10. The aqueous composition of claim 1, wherein the partially neutralized acid-functional support resin of the second polymer is neutralized with a base selected from the group consisting of ammonia, sodium hydroxide, potassium hydroxide, organic amines, and mixtures thereof.

19. 10. The aqueous composition of claim 1, wherein partial neutralization refers to neutralization of at least 5 mol % of the acid groups on the acid-functional support resin with a base.

20. 20. The aqueous composition of any one of claims 1 to 19, wherein the second polymer comprises the partially neutralized acid-functional support resin in an amount of 10% to 50% by weight, and the at least one ethylenically unsaturated monomer in an amount ranging from 5% to 90% by weight, both based on the total weight of the second polymer.

21. 10. The aqueous composition of claim 1, further comprising a wax in an amount ranging from 0.10% to 25% by weight, based on the total weight of the aqueous composition.

22. 22. The aqueous composition of claim 21, wherein the wax is an aqueous emulsion.

23. 23. The aqueous composition of claim 22, wherein the aqueous emulsion is selected from the group consisting of paraffin, polyethylene, polypropylene, microcrystalline wax, fluorinated wax, ethylene copolymer wax, propylene copolymer wax, and mixtures thereof.

24. 24. The aqueous composition of claim 1, further comprising a surfactant.

25. 25. The aqueous composition of claim 24, wherein the surfactant is anionic or nonionic.

26. 26. The aqueous composition of claim 25, wherein the surfactant is selected from the group consisting of alkyl sulfonates, alkyl benzene sulfonates, alkyl sulfates, alkyl benzene sulfates, phosphates, phosphinates, aliphatic carboxylates, and mixtures thereof.

27. 26. The aqueous composition of claim 25, wherein the surfactant comprises at least one fatty alcohol ethoxylate.

28. 26. The aqueous composition of claim 25, wherein the surfactant comprises at least one alkyl sulfosuccinate ethoxylate.

29. 26. The aqueous composition of claim 25, wherein the surfactant comprises at least one alkyl sulfosuccinate ethoxylate and at least one fatty alcohol ethoxylate.

30. 26. The aqueous composition of claim 25, wherein the surfactant comprises at least one fatty alcohol having an alkyl chain length of from 12 carbons to 18 carbons and a degree of ethoxylation of from 10 moles of ethylene oxide units to 80 moles of ethylene oxide units.

31. 31. A substrate comprising at least one surface coated with at least one layer comprising the aqueous composition of any one of claims 1 to 30.

32. 32. The substrate of claim 31 which is paper or paperboard.

33. 31. A coated paper or article comprising the aqueous composition of any one of claims 1 to 30.

34. The aqueous composition is applied to 1 m of coated paper. 2 34. The coated paper or article of claim 33, comprising a coating weight in the range of 2 g to 30 g per coated paper or article.

35. 35. The coated paper or article of claim 34, exhibiting a blocking resistance of 3 or greater as determined according to ASTM WK20008 at 60°C and 60 psi for 24 hours.

36. 35. Coated paper or article according to claim 34, which exhibits oil and / or grease resistance.

37. 31. A method for making paper, comprising at least the step of contacting cellulose fibers with an aqueous composition according to any one of claims 1 to 30.

38. 38. The method of claim 37, wherein the step of contacting cellulose fibers with the aqueous composition comprises coating a paper web comprising cellulose fibers with an aqueous dispersion comprising the aqueous composition.

39. 38. The method of claim 37, wherein the step of contacting cellulose fibers with the aqueous composition comprises: (i) mixing cellulose fibers with an aqueous dispersion comprising the aqueous composition to form a slurry; and (ii) forming a paper web from the slurry of cellulose fibers and the aqueous composition.

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