Water-based adhesive composition including sugar alcohol and related methods

Abstract

A composition includes water, a polymeric adhesive dispersed in the composition, and a sugar alcohol. The sugar alcohol improves the freeze-thaw stability of the composition relative to a comparative composition that is the same as the composition except that it includes no sugar alcohol. A method for making a bonded article using the composition is also described. A method of improving freeze-thaw stability of a water-based adhesive composition and use of a sugar alcohol to improve freeze- thaw stability of a water-based adhesive composition comprising a polymeric adhesive dispersion are also described.

Description

[0001] WATER-BASED ADHESIVE COMPOSITION INCLUDING SUGAR ALCOHOL AND

[0002] RELATED METHODS

[0003] CROSS-REFERENCE TO RELATED APPLICATION

[0004] This application claims priority to U.S. Provisional Application No. 63 / 670,253, filed July 12, 2024, the disclosure of which is incorporated by reference in its entirety herein.

[0005] BACKGROUND

[0006] Contact adhesives and pressure-sensitive adhesives (PSAs) are useful for a variety of purposes. Applying such adhesives may involve applying an adhesive polymer composition in organic solvent or as an oil-in-water emulsion onto a substrate and subsequently removing the solvent or water. Water-based adhesives have significant advantages over their traditional solvent borne counterparts in that they can have low or no volatile organic compounds and can be nonflammable.

[0007] Some references that disclose water-based adhesives and / or water-soluble polymers are disclosed in U.S. Pat. Appl. Pub. No. 2023 / 0279280 (Thomas) and International Pat. Appl. Pub. No. WO 2020 / 169661, published August 27, 2020. Freeze-thaw instability has been reported as a problem for aqueous coating compositions in U.S. Pat. No. 10,752,793 (Velez et al.) and U.S. Pat. Appl. Pub. No. 2021 / 0222015 (Velez et al.).

[0008] SUMMARY

[0009] The present disclosure provides a composition that includes a polymeric adhesive and a sugar alcohol in water. Advantageously, the sugar alcohol can improve the freeze-thaw stability of the composition relative to a comparative composition that is the same as the composition except that it includes no sugar alcohol.

[0010] In one aspect, the present disclosure provides a composition that includes water, a polymeric adhesive dispersed in the water or the composition, and a sugar alcohol. The sugar alcohol improves the freeze-thaw stability of the composition relative to a comparative composition that is the same as the composition except that it includes no sugar alcohol.

[0011] In another aspect, the present disclosure provides a use of a sugar alcohol to improve freeze-thaw stability of a water-based adhesive composition including a polymeric adhesive dispersion.

[0012] In another aspect, the present disclosure provides a method of improving freeze-thaw stability of a water-based adhesive composition including a polymeric adhesive dispersion. The method involves including a sugar alcohol in the water-based adhesive composition.

[0013] In another aspect, the present disclosure provides a method for making a bonded article that includes a first substrate and a second substrate. The method includes applying the aforementioned composition on at least one of the first substrate or the second substrate and adhering the first substrate and the second substrate together using the composition.

[0014] In this application, terms such as "a", "an" and "the" are not intended to refer to only a singular entity but include the general class of which a specific example may be used for illustration. The terms "a", "an", and "the" are used interchangeably with the term "at least one". The phrases "at least one of and "comprises at least one of followed by a list refers to any one of the items in the list and any combination of two or more items in the list. All numerical ranges are inclusive of their endpoints and non-integral values between the endpoints unless otherwise stated (e.g., 1 to 5 includes 1, 1.5, 2, 2.75, 3, 3.8, 4, and 5, and the like).

[0015] The terms "first" and "second" are used in this disclosure in their relative sense only. It will be understood that, unless otherwise noted, those terms are used merely as a matter of convenience in the description of one or more of the embodiments.

[0016] As used herein, the term "acrylic" or "acrylate" includes compounds having at least one of acrylic or methacrylic groups.

[0017] The term “(meth)acrylate” with respect to a monomer, oligomer or polymer means a vinylfunctional alkyl ester formed as the reaction product of an alcohol with an acrylic or a methacrylic acid.

[0018] The term "polymer" refers to a molecule having a structure which includes the multiple repetition of units derived, actually or conceptually, from one or more monomers. The term “monomer” refers to a molecule of low relative molecular mass that can combine with others to form a polymer. The term “polymer” includes homopolymers and copolymers, as well as homopolymers or copolymers that may be formed in a miscible blend, e.g., by coextrusion or by reaction. The term “polymer” includes random, block, graft, and star polymers. The term “polymer” encompasses oligomers.

[0019] The term "crosslinking” refers to joining polymer chains together by covalent chemical bonds, usually via crosslinking molecules or groups, to form a network polymer. A crosslinked polymer is generally characterized by insolubility but may be swellable in the presence of an appropriate solvent.

[0020] "Alkyl group" and the prefix "alk-" are inclusive of both straight chain and branched chain groups and of cyclic groups. In some embodiments, alkyl groups have up to 30 carbons (in some embodiments, up to 25, 20, 18, 16, or 15 carbons) unless otherwise specified. Cyclic groups can be monocyclic or polycyclic.

[0021] The term “hydrocarbon” refers to compounds that have only carbon and hydrogen atoms.

[0022] The above summary of the present disclosure is not intended to describe each disclosed embodiment or every implementation of the present disclosure. The description that follows more particularly exemplifies illustrative embodiments. It is to be understood, therefore, that the following description is for illustration purposes only and should not be read in a manner that would unduly limit the scope of this disclosure. DETAILED DESCRIPTION

[0023] Water-based adhesives can be subjected to freezing and thawing cycles during storage and shipping due to a lack of temperature control. Under such conditions, the colloidal stability of latex polymer particles is compromised and can result in changes in formulation viscosity. This problem can result in the water-based adhesive to be unusable in many instances and can even result in the polymer becoming a solid mass in the water.

[0024] Solvents such as glycols have been historically used to protect paints and coatings from freezethaw stability problems. We have observed that such glycols are not effective at stabilizing some waterbased adhesives. The present disclosure provides water-based compositions that typically, and advantageously, are stable after being exposed to one or more freeze-thaw cycles. The composition comprises water, a polymeric adhesive dispersed in the water or the composition, and a sugar alcohol.

[0025] In some embodiments, the polymeric adhesive is a pressure-sensitive adhesive (PSA). PSAs are well known to those of ordinary skill in the art to possess properties including the following: (1) aggressive and permanent tack, (2) adherence with no more than finger pressure, (3) sufficient ability to hold onto an adherend, and typically, (4) sufficient cohesive strength to be cleanly removable from the adherend. PSAs are tacky and have the ability to adhere without activation by any energy source such as light, heat, or a chemical reaction. Materials that have been found to function well as PSAs are polymers designed and formulated to exhibit the requisite viscoelastic properties resulting in a desired balance of tack, peel adhesion, and shear holding power. One method useful for identifying pressure sensitive adhesives is the Dahlquist criterion. This criterion defines a pressure sensitive adhesive as an adhesive having a creep compliance of greater than 3 x 10’6cm2 / dyne as described in Handbook of Pressure Sensitive Adhesive Technology, Donatas Satas (Ed.), 2nd Edition, p. 172, Van Nostrand Reinhold, New York, NY, 1989. Alternatively, since modulus is, to a first approximation, the inverse of creep compliance, pressure sensitive adhesives may be defined as adhesives having a storage modulus of less than about 3 x 105N / m2.

[0026] In some embodiments, the polymeric adhesive is a contact adhesive. As used herein, the term “contact adhesive” refers to an adhesive which is typically applied to two surfaces to be adhered together. The adhesive is allowed some dry time to form clear adhesive layer(s) and brought into contact with pressure so as to form a fast acting, if not an immediate, durable bond. Once the contact adhesives have been pressed together, the adhered pieces are ready for further processing, e.g., cutting. Contact adhesives are generally formulated so that no adhesive curing (e.g., chemical reaction) is required to achieve the desired adhesion.

[0027] The composition of the present disclosure and / or useful for practicing the present disclosure comprises water and a polymeric adhesive dispersed in the water or the composition. By “dispersed”, it is meant that the polymeric adhesive in water is a heterogeneous mixture of discrete particles or droplets in water. “Dispersed” does not encompass “dissolved”. Generally, therefore, the polymeric adhesive is insoluble in water (that is, has a solubility of less than 5 grams (g) per liter, less than 1 g per liter, or less than 0.5 g per liter at 20 °C). The polymeric adhesive may be a liquid or solid in the water; therefore, the dispersion of polymeric adhesive in water may be an emulsion, latex, or colloidal suspension. Examples of useful polymeric adhesives that can be dispersed in water include acrylic polymers, polychloroprene, polyurethane, natural rubber, synthetic polyisoprene, polybutadiene, styrene / butadiene rubber (SBR), styrene / isoprene / butadiene rubber, and acrylonitrile butadiene rubber. Various backbone geometries and connectivities may be present in these polymers, for example, in polybutadiene and polyisoprene, a high amount of cis geometry may be present. Combinations of two or more of these polymeric adhesives may be present in the composition, for example, natural rubber and SBR. In some embodiments, the polymeric adhesive comprises at least one of an acrylic polymer, polyurethane, or poly chloroprene. In some embodiments, the polymeric adhesive comprises at least one of an acrylic polymer or polychloroprene. In some embodiments, the polymeric adhesive comprises poly chloroprene. The polymeric adhesive dispersed in water does not include water-soluble polymers such as starch. In some embodiments, the polymeric adhesive dispersed in water also does not include a polypeptide (in some embodiments, gelatin, which rapidly absorbs and / or dissolves in water).

[0028] The weight average molecular weight (Mw) of the polymeric adhesive can be in a range from, for example, 10,000 to 1,000,000 grams per mole, 50,000 to 500,000 grams per mole, or 50,000 to 200,000 grams per mole, as determined by gel permeation chromatography using a polystyrene standard.

[0029] The polymeric adhesive dispersed in water may have a particle or droplet size in a range from 50 nanometers (nm) to 10 micrometers, from 50 nanometers to 5 micrometers, or from 200 nanometers to 500 nanometers as determined by dynamic light scattering measurements, which is a technique known to a person skilled in the art of aqueous dispersions. In some embodiments, the droplet or particle size is 500 nm or less, 400 nm or less, or 300 nm or less. In some embodiments, the droplet or particle size is at least 50 nm, at least 100 nm, or at least 130 nm.

[0030] In some embodiments, the polymeric adhesive includes an acrylic polymer. As used herein, "acrylic", and like terms, is meant to encompass both acrylates and methacrylates. A variety of acrylic polymers may be useful in the composition. In some embodiments, the acrylic polymer is made from hydrophobic acrylic monomers including acrylate and / or methacrylate esters of a linear or branched alcohol having at least 4 carbon atoms (in some embodiments, 4 to 14 carbon atoms, 4 to 10 carbon atoms, 4 to 8 carbon atoms, or 6 to 8 carbon atoms). Examples of such monomers, which are suitable for use in the acrylic polymer, include isooctyl acrylate, 4-methyl-2-pentyl acrylate, 2-methyl-butyl acrylate, isoamyl acrylate, sec-butyl acrylate, n-butyl acrylate, 2-ethylhexyl acrylate, isodecyl methacrylate, isononyl acrylate, isodecyl acrylate, and mixtures thereof. Other suitable monomers for use in preparing the acrylic polymer include at least partially hydrophilic monomers such as acrylic acid, methacrylic acid, fumaric acid, maleic acid, itaconic acid, crotonic acid, oligomeric acrylic acid, 2-hydroxyethyl acrylate, methyl (meth)acrylate, ethyl (meth)acrylate, N-vinyl-2 -pyrrolidone, and mixtures thereof. Such hydrophilic monomers are typically used in amounts of up to 2, 1, or 0.5 percent by weight, based on the total weight of monomers used to make the acrylic polymer. If acid functional groups are present in the acrylic polymer, they can be neutralized using, for example, amines (e.g., dimethylethanolamine, ammonia, triethanolamine, dimethylethyl ethanolamine, and N',N'-dimethyl aminopropylamine) or alkali metal salts (e.g., sodium or potassium hydroxide). Other monomers may be usefully incorporated into the acrylic polymer, for example, styrene, vinyl toluene, nitriles (e.g., acrylonitrile and methacrylonitrile), vinyl and vinylidene halides, and vinyl esters (e.g., vinyl acetate).

[0031] In addition to acid-functional monomers, the acrylic polymer can further comprise monomer units of other polar monomers including at least one ketone, amide, amine, alcohol or combination thereof. Examples of polar monomers with a hydroxyl group include hydroxyalkyl (meth)acrylates (e.g., 2- hydroxyethyl (meth)acrylate, 2-hydroxypropyl (meth)acrylate, 3 -hydroxypropyl (meth)acrylate, and 4- hydroxybutyl (meth)acrylate), hydroxyalkyl (meth)acrylamides (e.g., 2-hydroxyethyl (meth)acrylamide or 3 -hydroxypropyl (meth)acrylamide), ethoxylated hydroxyethyl (meth)acrylate (e.g., monomers commercially available from Sartomer (Exton, PA, USA) under the trade designation CD570, CD571, and CD572), and aryloxy substituted hydroxyalkyl (meth)acrylates (e.g., 2 -hydroxy-2 -phenoxypropyl (meth)acrylate). Examples of polar monomers with a primary amido group include (meth)acrylamide. Examples of polar monomers with secondary amido groups include N-alkyl (meth)acrylamides such as N-methyl (meth)acrylamide, N-ethyl (meth)acrylamide, N-isopropyl (meth)acrylamide, N-tert-octyl (meth)acrylamide, and N-octyl (meth)acrylamide. Examples of polar monomers with a tertiary amido group include N-vinyl caprolactam, N-vinyl-2 -pyrrolidone, (meth)acryloyl morpholine, and N,N-dialkyl (meth)acrylamides such as N,N-dimethyl (meth)acrylamide, N,N-diethyl (meth)acrylamide, N,N-dipropyl (meth)acrylamide, and N,N -dibutyl (meth)acrylamide. Polar monomers with an amino group include various N,N-dialkylaminoalkyl (meth)acrylates and N,N-dialkylaminoalkyl (meth)acrylamides. Examples include N,N-dimethyl aminoethyl (meth)acrylate, N,N-dimethylaminoethyl (meth)acrylamide, N,N- dimethylaminopropyl (meth)acrylate, N,N-dimethylaminopropyl (meth)acrylamide, N,N- diethylaminoethyl (meth)acrylate, N,N-diethylaminoethyl (meth)acrylamide, N,N-diethylaminopropyl (meth)acrylate, and N,N-diethylaminopropyl (meth)acrylamide. Examples of polar monomers that include ketones include diacetone acrylamide and acetoacetoxy ethyl methacrylate. In some embodiments, not more than 2, 1, 0.5, 0.25, 0.1, 0.05, or 0.01 percent by weight of monomer units in the acrylic polymer useful in the compositions and methods of the present disclosure include at least one ketone, amide, amine, alcohol or combination thereof. The acrylic polymer may be free of polar monomer units.

[0032] Crosslinked acrylic polymer adhesives may be made, for example, by including one or more polyfunctional crosslinking monomers (e.g., multifunctional acrylate or multifunctional methacrylate) in the monomers used to make the polymer. Suitable polyfunctional monomers include diacrylate esters of diols, such as ethylene glycol diacrylate, diethylene glycol diacrylate, propanediol diacrylate, butanediol diacrylate, butane-l,3-diyl diacrylate, pentanediol diacrylate, hexanediol diacrylate (including 1,6- hexanediol diacrylate), heptanediol diacrylate, octanediol diacrylate, nonanediol diacrylate, decanediol diacrylate, and dimethacrylates of any of the foregoing diacrylates. Further suitable polyfunctional monomers include polyacrylate esters of polyols, such as glycerol triacrylate, dipropylene glycol diacrylate, tripropylene glycol diacrylate, trimethylolpropane triacrylate, pentaerythritol tetraacrylate, neopentyl glycol diacrylate, dipentaerythritol pentaacrylate, methacrylates of the foregoing acrylates, and combinations thereof. Further suitable polyfunctional crosslinking monomers include divinyl benzene, allyl methacrylate, diallyl maleate, diallyl phthalate, and combinations thereof. Further suitable polyfunctional crosslinking monomers include polyfunctional acrylate oligomers comprising two or more acrylate groups. The polyfunctional acrylate oligomer may be a urethane acrylate oligomer, an epoxy acrylate oligomer, a polyester acrylate, a polyether acrylate, a polyacrylic acrylate, a methacrylate of any of the foregoing acrylates, or a combination thereof. Combinations of any of these crosslinking monomers may be useful. In some embodiments, not more than 1, 0.5, 0.25, 0.1, 0.05, or 0.01 percent by weight of monomer units in the acrylic polymer useful in the compositions and methods of the present disclosure are derived from crosslinking monomers. The acrylic polymer may be free of crosslinking monomer units.

[0033] Other crosslinking monomer units may be present in the acrylic polymer useful as a polymeric adhesive. In some embodiments, the acrylic polymer can undergo crosslinking upon removal of the water. N-Methylolacrylamide (NMA) is a monomer useful for incorporating an N-methylol group into an acrylic polymer, for example. The methylol group of one acrylic polymer chain can react with a methylol group of another acrylic polymer chain with cleavage of formaldehyde and water molecule to provide crosslinking. Unsaturation in silanes, such as vinylsilane and methacryloxysilanes allows incorporation into an acrylic polymer chain. Upon drying of the coating, the pH drops and triggers the hydrolysis of the alkoxysilane into a silanol (Si-OH), which then unites with a second silanol available on the polymer chain and forms a siloxane (Si-O-Si) bond. Acrylic monomers comprising an aldehyde and / or ketone functional group (e.g., diacetone acrylamide, acrolein, vinyl methyl ketone, acetoacetoxyethyl methacrylate, and allyl acetoacetate) can react with a crosslinking agent having at least two functional groups reactive with the carbonyl functionality of the acrylic copolymer. Any nitrogen-containing compound having at least two amine nitrogens reactive with carbonyl groups may be used as the crosslinking agent. Such crosslinking agents may be aliphatic or aromatic, polymeric or non-polymeric, and may be used singly or in a combination of two or more. Examples of suitable crosslinking agents include adipic acid dihydrazide, diamines (e.g., ethylenediamine, propylenediamine, tetramethylenediamine, pentamethylenediamine, hexamethylenediamine, diethylenetriamine, triethylenetetramine), and tetraaminoethylene. In some embodiments, the crosslinking agent is present in the composition in an amount such that the functional groups (e.g., hydrazide groups) reactive with the carbonyl functionality of the acrylic polymer are in a range of 0.02 to 5 equivalents, 0. 1 to 3 equivalents, or 0.5 to 2 equivalents per one equivalent of carbonyl group contained in the acrylic polymer. In some embodiments of a composition of the present disclosure, after the composition is applied to a substrate and as water in the emulsion evaporates, the hydrazide groups and the carbonyl groups crosslink as a result of dehydration condensation. Polymeric adhesives dispersed in water can be made, for example, by emulsion polymerization in which monomers, such as any of those described above, are polymerized in water, optionally in the presence of an emulsifier, catalyst, and / or a chain-transfer agent (e.g., carbon tetrabromide, alcohols, mercaptans such as, for example, isooctyl thioglycolate, and mixtures thereof).

[0034] In some embodiments, the acrylic polymer useful as a polymeric adhesive is core-shell polymer having different monomer compositions in the core and the shell. A core-shell polymer can be made by emulsion polymerization, for example, in which the monomer composition is changed during the polymerization to provide polymer particles with cores having a different glass transition temperature or a different reactivity from the shell. Examples of core-shell polymers that may be useful as polymeric adhesives include those described in U.S. Pat. Nos. 5,461,125 (Lu et al.) and 10,221,343 (Qie et al.).

[0035] Some acrylic polymers useful for practicing the present disclosure are commercially available, for example, as emulsions from Alberdingk Boley, Greensboro, N.C., under the trade designations “AC 2403”, “AC 3630”, and “AC 2514”, from Dow, Midland, Mich., under the trade designation “RHOPLEX” in grades “AC- 1034”, “GL-618”, and CS-4000, from The Lubrizol Corporation, Wickliffe, Ohio, under the trade designation “CARBOSET GA 7487”, from BASF, Ludwigshafen, Germany, under the trade designation “ACRONAL”, and from Arkema, King of Prussia, PA, under the trade designation “ENCOR”.

[0036] Polyurethanes useful in the composition of the present disclosure may be formed using any suitable reactants and any suitable process. Polyurethanes are typically formed from starting materials that include one or more isocyanates, one or more polyols, and optionally one or more additional reactants (e.g., having one or more active hydrogen groups). In some cases, a stoichiometric excess of isocyanate is reacted with the polyol. For example, a ratio of isocyanate groups to hydroxyl groups can range from about 1.1: 1 to 3: 1 (NCO:OH), from about 1.2: 1 to 2.5: 1, or from about 1.3: 1 to 2: 1. The polyurethane may have any suitable molecular weight, for example, a number average molecular weight from about 1,000 to about 10,000 or from about 2,500 to about 7,500.

[0037] Suitable isocyanates include those having one, two, three, or four isocyanate groups and mixtures thereof. Suitable diisocyanates include isophoronediisocyanate (i.e., 5 -isocyanato- 1-isocyanatomethyl- 1 ,3 ,3 -trimethylcyclohexane); 5 -isocyanato- 1 -(2-isocyanatoeth- 1 -yl)- 1 ,3 ,3 -trimethylcyclohexane; 5 - isocyanato- 1 -(3 -isocyanatoprop- 1 -yl)- 1 ,3 ,3 -trimethylcyclohexane; 5 -isocyanato-(4-isocyanatobut- 1 -yl)- 1 ,3 ,3 -trimethylcyclohexane; 1 -isocyanato-2-(3 -isocyanatoprop- 1 -yl)cyclohexane ; 1 -isocyanato-2-(3 - isocyanatoeth- 1 -yl)cyclohexane; 1 -isocyanato-2-(4-isocyanatobut- 1 -yl)cyclohexane; 1 ,2- diisocyanatocyclobutane; l,3-diisocyanatocyclobutane;l,2-diisocyanatocyclopentane; 1,3- diisocyanatocyclopentane; 1,2-diisocyanatocyclohexane; 1,3-diisocyanatocyclohexane; 1,4- diisocyanatocyclohexane; dicyclohexylmethane 2,4'-diisocyanate; trimethylene diisocyanate; tetramethylene diisocyanate; pentamethylenediisocyanate; hexamethylene diisocyanate; ethylethylene diisocyanate ;trimethylhexane diisocyanate; heptamethylene diisocyanate; 2-heptyl-3,4-bis(9- isocyanatononyl)-l-pentyl-cyclohexane; 1,2-, 1,4-, andl,3-bis(isocyanatomethyl)cyclohexane; 1,2-, 1,4-, and l,3-bis(2-isocyanatoeth-l-yl)cyclohexane; l,3-bis(3-isocyanatoprop-l-yl)cyclohexane; 1,2-, 1,4- or l,3-bis(4-isocyanatobuty-l-yl)cyclohexane; liquid bis(4-isocyanatocyclohexyl)-methane; and derivatives or mixtures thereof. In some embodiments, the isocyanate or mixture of isocyanates is non-aromatic (e.g., aliphatic). In some embodiments, the isocyanate comprises at least one of isophorone diisocyanate (IPDI) or hexamethylene diisocyanate (HMDI).

[0038] Suitable polyols for preparing polyurethanes include monomers, oligomers, polymers, and mixtures thereof and include diols, triols, polyols having 4 or more hydroxyl groups, and mixtures thereof. Examples of polyols for use as reactants or as starting materials for oligomer or polymer polyols include ethylene glycol, propylene glycol, 1,3 -propanediol, glycerol, diethylene glycol, dipropylene glycol, triethylene glycol, trimethylolpropane, trimethylolethane, tripropyleneglycol, neopentyl glycol, pentaerythritol, 1,4-butanediol, hexyleneglycol, cyclohexanedimethanol, a polyethylene or polypropylene glycol, isopropylidene bis(p-phenylene-oxypropanol-2), and mixtures thereof. Examples of suitable oligomer and / or polymer polyols include polyether polyols, polyester polyols, polyether-ester polyols, polyureapolyols, polyamide polyols, polycarbonate polyols, saturated or unsaturated polyolefin polyols, and combinations thereof.

[0039] In some embodiments, the polyurethane is formed through a prepolymer intermediate having at least one isocyanate group, in some embodiments, having at least two terminal isocyanate groups. Such isocyanate-terminated prepolymers may be produced, for example, by reacting a material having at least two active hydrogen groups per molecule with an isocyanate compound, such as a diisocyanate. Suitable "active hydrogen groups" include groups having a hydrogen attached to oxygen (O), sulfur (S), and / or nitrogen (N) atoms (e.g., -OH, -COOH, -SH, and -NH2). The material may be an oligomeric or polymeric material such as an acrylic, alkyd, polyester, polyether, polyamide, or a mixture thereof.

[0040] In some embodiments, the polyurethane includes a sufficient number of salt groups or saltforming groups to provide a stable aqueous dispersion when it is combined with an aqueous carrier. In some embodiments, a monomer or oligomer having salt groups or salt-forming groups may be included in the reactants used to produce the polyurethane. In some embodiments, an acid- or anhydride-functional, salt-forming monomer such as dimethylolpropionic acid or trimellitic anhydride is used to form the polyurethane. Alternatively, a prepolymer may be reacted with a compound including a salt group or saltforming group. In some embodiments, the polyurethane includes acid or anhydride groups (or other neutralizable groups capable of forming anionic salt groups) that are neutralized with a tertiary amine.

[0041] Some polyurethanes useful for practicing the present disclosure are commercially available, for example, as emulsions from Alberdingk Boley, under the trade designations “U 4101”, “U 4000”, “U 915”, and “U 933”, from The Lubrizol Corporation, Wickliffe, OH, under the trade designation “SANCURE”, and from BASF, Ludwigshafen, Germany, under the trade designation “EPOTAL”.

[0042] Poly chloroprene is made by polymerization of 2-chlorobuta- 1,3 -diene. The temperature of polymerization affects the trans and cis content in the polymer, with more cis content resulting from higher polymerization temperatures. A higher trans content in the polymer results in a higher degree of crystallization. Vicinal vinyl groups resulting from 1,2 addition instead of 1,4 addition can be useful for grafting other monomers onto the polymer such as (meth)acrylic acid groups, (meth)acrylates, and acrylonitrile. Poly chloroprene can also be vulcanized with sulfur. Poly chloroprene dispersions in water can be stabilized with rosin acid-based emulsifiers, which can also act as tackifiers, described in further detail below. Some poly chloroprenes useful for practicing the present disclosure are commercially available, for example, as emulsions from Covestro AG, Leverkusen, Germany, under the trade designation “DISPERCOLL” and from Vanderbilt Chemicals, LLC, Norwalk, CT, USA under the trade dsignation “NEOPRENE”. Further, an example of a useful water-dispersed, sprayable poly chloroprene- based contact adhesive is obtained under the trade designation “3M FASTBOND Contact Adhesive 30- NF” from 3M Company, St. Paul, MN, USA.

[0043] Some natural rubber polymers and SBR polymers useful for practicing the present disclosure are commercially available, for example, as emulsions from Alcan Rubber and Chemical, New York, NY, under the trade designation “ALCANTEX” and from BASF under the trade designation “BUTOFAN”.

[0044] The various polymeric adhesives described above may have varying pH values at which they are useful. For example, natural rubber emulsions may be useful at pH 13 or 14. In some embodiments, the composition of the present disclosure further comprises base, for example, to raise the pH. In some embodiments, the pH is raised to at least 7, 8, 9, 10, 11, 12, or 13. Examples of suitable bases include ammonia (e.g., aqueous ammonia or ammonium hydroxide), ethanolamine, sodium hydroxide, triethylamine, and sodium carbonate.

[0045] Depending on the amount of sugar alcohol and any of the tackifiers and other additives described below, in some embodiments, the composition of the present disclosure may include at least 70 weight percent (wt.%), 75 wt.%, 80 wt.%, 90 wt.%, 95 wt.%, 98 wt.%, or 99 wt.% of the polymeric adhesive described above in any of its embodiments, based on the total amount of solids in the composition (that is, excluding water). In some embodiments, the polymeric adhesive is present in the composition in an amount of at least 40 wt.% and / or not more than 60 wt.%, based on the total weight of the composition (that is, including water).

[0046] The composition of the present disclosure and / or useful for practicing the present disclosure comprises a sugar alcohol. In some embodiments, the sugar alcohol comprises at least one of sorbitol, maltitol, xylitol, or erythritol. In some embodiments, the sugar alcohol comprises sorbitol. Sorbitol can be obtained neat or as a solution in water (e.g., 70 wt.% from WEGO Chemical Group, Great Neck, NY, USA).

[0047] In some embodiments, the sugar alcohol, which may be any of sorbitol, maltitol, xylitol, or erythritol, is present in the composition in an amount of at least 1.5 wt.% or not more than ten wt.%, based on the total weight of the composition. In some embodiments, the sugar alcohol is present in the composition in an amount of at least 1.75 wt.% or 2.0 wt.%, based on the total weight of the composition. In some embodiments, the sugar alcohol is present in the composition in an amount of not more than 9 wt.%, 8 wt.%, 7 wt.%, 6 wt.%, 5 wt. %, or 4 wt.%, based on the total weight of the composition. In some embodiments, if the sugar alcohol is present in the composition in an amount of less than 1.5 wt.%, it may not improve the freeze-thaw stability of the composition relative to a composition that does not include the sugar alcohol. In some embodiments, if the sugar alcohol is present in the composition in an amount of more than 10 wt.%, it may negatively affect the adhesion strength of an adhesive formed from the composition.

[0048] In some embodiments of the composition of the present disclosure and / or useful for practicing the present disclosure, the composition further comprises a tackifier. In some embodiments, the tackifier comprises at least one of rosin, a rosin ester, an ester of hydrogenated rosin, a polyterpene (e.g., those based on a-pinene, P-pinene, or limonene), an aliphatic hydrocarbon resin (e.g., those based on cis- or trans-piperylene, isoprene, 2-methyl-but-2-ene, cyclopentadiene, dicyclopentadiene, or combinations thereof), an aromatic resin (e.g. those based on styrene, a-methyl styrene, methyl indene, indene, coumarone, or combinations thereof), or a mixed aliphatic-aromatic hydrocarbon resin. In some embodiments, the tackifier comprises at least one of a terpene resin, a rosin, a rosin ester, an ester of hydrogenated rosin, an aliphatic hydrocarbon resin, an aromatic resin, or a mixed aliphatic -aromatic hydrocarbon resin. The aromatic hydrocarbon resins may be C9-type petroleum resins obtained by copolymerizing a C9 fraction produced by thermal decomposition of petroleum naphtha, and aliphatic hydrocarbon resins may be C5-type petroleum resins obtained by copolymerizing a C5 fraction produced by thermal decomposition of petroleum naphtha. Mixed aliphatic / aromatic resins may be C5 / C9-type petroleum resins obtained by polymerizing a combination of a C5 fraction and C9 fraction produced by thermal decomposition of petroleum naphtha. Any of these tackifying resins may be hydrogenated (e.g., partially, or completely). The term rosin, as employed herein, includes natural rosin, refined or unrefined (refined rosin will usually contain, by weight, about 90% of rosin acids and about 10% of inert material), such as natural wood rosin, natural gum rosin, and tall oil rosin; modified rosin, refined or unrefined, such as disproportionated rosin, hydrogenated rosin, and polymerized rosin; and the pure or substantially pure acids, of which rosin is comprised, alone or in admixture. In some embodiments, the tackifier is a hydrocarbon tackifier. In some embodiments, useful tackifiers can have a number average molecular weight of up to 10,000 grams per mole, a softening point of at least 30 °C as determined using a ring and ball apparatus, and a glass transition temperature of at least -30 °C as measured by differential scanning calorimetry. Useful tackifiers are typically amorphous. In some embodiments, the tackifier is miscible with the polymeric adhesive of the composition such that macroscopic phase separation does not occur in the composition. In some embodiments, a combination of tackifiers may be useful to obtain a good balance of compatibility and adhesive performance (e.g., high temperature performance).

[0049] Some suitable tackifiers are commercially available as emulsions under the trade designations "TACOLYN" from Eastman Chemical, Kingsport, TN, and “AQUATAC” from Kraton Corporation, Houston, TX.

[0050] In some embodiments, the tackifier is present in the composition in a range from two parts to 30 parts by weight per one hundred parts of the polymeric adhesive. In some embodiments, the tackifier is present in a range from 2 to 25, 2 to 20, 5 to 25, 10 to 25, 10 to 20, 2 to 15, or 2 to 10 parts by weight per one hundred parts of the polymeric adhesive.

[0051] In some embodiments, the composition of the present disclosure and / or useful for practicing the present disclosure further comprises an emulsifier. An emulsifier used in an emulsion polymerization to form the polymeric adhesive is typically present in the composition of the present disclosure. In some embodiments, the emulsifier is an anionic surfactant. Useful anionic surfactants include those that include at least one hydrophobic moiety such as an about 6 carbon atom- to about 12 carbon atom-alkyl, alkylaryl, and / or alkenyl group as well as at least one anionic group selected from carboxylate, sulfate, sulfonate, phosphate, polyoxyethylene sulfate, polyoxyethylene sulfonate, polyoxyethylene phosphate, and / or salts of such anionic groups such as alkali metal salts (e.g., sodium, potassium) and ammonium salts. Any fatty acid soap (e.g., alkyl succinates), ethoxylated fatty acids, and / or the alkali metal salts or ammonium salts thereof, dialkylsulfosuccinates, and sulfated oils may be useful. Some useful anionic surfactants include sodium lauryl sulfate, sodium lauryl ether sulfate, sodium dodecylbenzene sulfonate and sulfosuccinate esters. Representative commercial examples of anionic surfactants include sodium lauryl sulfate, available from Stepan Chemical Co. under the trade designation “POLYSTEP B-3”; sodium lauryl ether sulfate, available from Stepan Chemical Co. under the trade designation “POLYSTEP B-12”; and sodium dodecylbenzene sulfonate, available from Rhodia, Incorporated, under the trade designation “RHODACAL DS-10”. Combinations of any of these surfactants may be useful.

[0052] In some embodiments, the emulsifier is copolymerizable with the monomer or monomer mixture and becomes incorporated into the polymeric adhesive. The copolymerizable emulsifier has at least one group, or only one group, capable of reacting with the monomer or monomer mixture. Such reactive groups include ethylenically unsaturated groups such as vinyl groups and acrylate groups. Examples of polymerizable emulsifiers include sodium styrene sulfonate (commercially available from Alfa Aesar), sodium vinylsulfonate, polysodium styrene sulfonate, polyoxyethylene alkylphenyl ether ammonium sulfates those obtained under the trade designation “HITENOL BC” from Montello, Inc., Kyoto, Japan, including polyoxyethylene nonylpropenyl phenyl ether ammonium sulfate, polyoxyethylene styrenated phenyl ether ammonium sulfates such as those obtained under the trade designation “HITENOL AR” from Montello, Inc., and polyoxyethylene alkylether sulfuric esters such as those obtained under the trade designation “HITENOL KH” from Montello, Inc.

[0053] The total amount of surfactant in the composition of the present disclosure and / or useful for practicing the present disclosure is typically 5 wt.% or less, 3 wt.% or less, 2 wt.% or less, 1.75 wt.% or less, 1.5 wt.% or less, or 1.3 wt.% of less based on the total weight of the solids in the composition (that is, excluding water). In some embodiments, the total amount of emulsifier employed is anionic in nature.

[0054] In some embodiments a nonionic surfactant may be employed if desired. In some embodiments, the nonionic surfactant is available in a small amount (e.g., less than 5 wt.% of the total surfactant amount). Such surfactants are well known to those skilled in the art. Representative commercial examples of nonionic surfactants include the “TRITON X” series of surfactants (octylphenol ethoxylates), “TRITON CG 600” (a polyalkyl glucoside) available from Dow Chemical Company, and polymerizable surfactants including polyoxyethylene alkylphenyl ethers such as those obtained under the trade designation “NOIGEN RN” from Montello, Inc.

[0055] In addition to water and the polymeric adhesive, sugar alcohol, tackifier, and emulsifier as described above in any of their embodiments, the following additives may also optionally be included in the compositions of the present disclosure and / or useful for practicing the present disclosure: inhibitors such as hydroquinone, pigments, dyes, rheology modifiers, thickeners, plasticizers, antioxidants (e.g., hindered phenols, amines, and sulfur and phosphorous hydroperoxide decomposers), stabilizers (e.g., ultraviolet absorbers, hindered amine light stabilizers, and heat stabilizers), fillers (e.g., inorganic fillers such as talc, zinc oxide, titanium dioxide, aluminum oxide), preservatives, biocides, corrosion inhibitors, fire retardants, and defoamers. These and other conventional additives, if used, are present in conventional concentrations known to those skilled in the art and to the extent they do not unacceptably affect the advantages provided by the present disclosure.

[0056] The composition of the present disclosure and / or useful for practicing the present disclosure includes water. The amount of water in the composition is typically at least 25 wt.% or 30 wt.%, based on the total weight of the composition. The amount of water in the composition can be up to 75 wt.%, 70 wt.%, 65 wt.%, 60 wt.%, 55 wt.%, 50 wt.%, 45 wt.%, or 40 wt.% by weight, based on the total weight of the composition. Useful amount of water in the compositions can be in a range from 25 wt.% to 60 wt.%, 30 wt.% to 50 wt.%, or 40 wt.% to 60 wt.%, based on the total weight of the composition.

[0057] In some embodiments, the composition of the present disclosure and / or useful for practicing the present disclosure is substantially free of organic solvents. Common organic solvents include any of those have a boiling point of up to 150 °C at atmospheric pressure. The term “substantially free” means that composition can include up to 0.5, 0.1, 0.05, or 0.01 percent by weight of any of these solvents or can be free of any of these solvents. These percentages are based on the total weight of the composition.

[0058] In some embodiments, the composition of the present disclosure and / or useful for practicing the present disclosure further comprises organic solvent. Useful organic solvents include those that are compatible with water and can provide a homogeneous composition. Examples of useful solvents include esters (e.g., methyl acetate and butyl acetate), alcohols (e.g., methanol, ethanol, and isopropyl alcohol), polyols (e.g., ethylene glycol, propylene glycol, and glycerol), and ketones (e.g., acetone). In some embodiments, the organic solvent comprises at least one of ethyl acetate, ethanol, or acetone. The total amount of organic solvent is typically 20 wt.% or less, 10 wt.% or less, 5 wt.% or less, or 1 wt.% or less, and may be more than 0.5 wt.%, at least 1 wt.%, at least 2 wt.%, at least 3 wt.%, at least 4 wt.%, or at least 5 wt.%, based on the total weight of the composition.

[0059] A process for making the composition of the present disclosure can include combining components comprising a solution of the sugar alcohol dissolved in at least a portion of the water with an emulsion of the polymeric adhesive. It is also possible to combine a neat sugar alcohol and the emulsion of the polymeric adhesive. Other components may be combined into the composition as solids, liquids, dissolved in water, or emulsified in water. In embodiments in which the composition includes a tackifier, a second emulsion of the tackifier may be combined with an emulsion of the polymeric adhesive, which may include the sugar alcohol. The order of addition is not limited. In some embodiments, the emulsion that includes the polymeric adhesive also includes the tackifier. In some embodiments, the monomers used to make the polymeric adhesive may be polymerized in the presence of the tackifier. For example, a tackifier and at least one alkyl (meth)acrylate may be combined to form a solution, which may be combined with the water and the emulsifier. The at least one alkyl (meth)acrylate may then be polymerized to form an emulsion with droplets or particles that include both the acrylic polymer and the tackifier. The solution can include any of the other optional monomers described above.

[0060] The present disclosure provides the use of a sugar alcohol to improve freeze-thaw stability of a water-based adhesive composition comprising a polymeric adhesive dispersion. Similarly, the present disclosure provides a method of improving freeze-thaw stability of a water-based adhesive composition comprising a polymeric adhesive dispersion, the method comprising including a sugar alcohol in the water-based adhesive composition. The person skilled in the art can readily determine whether the sugar alcohol improves the freeze-thaw stability of the composition by adding the sugar alcohol to polymeric adhesive dispersion and subjecting it to the freeze-thaw cycle described in the Examples below. As used herein “improve” means that without the sugar alcohol, the comparative composition does not return to a stable emulsion after a freeze-thaw cycle. For example, it remains as a solid mass or has solid inhomogeneities. Further, the term “improve” means that with the sugar alcohol, the composition returns to a stable emulsion after the freeze-thaw cycle or contains fewer solid inhomogeneities (e.g., clumping or stringing) than the comparative composition. As shown in the Examples below, the sugar alcohols described herein allow the water-dispersed, sprayable poly chloroprene -based contact adhesive obtained under the trade designation “3M FASTBOND Contact Adhesive 30-NF” from 3M Company to remain a dispersion after one or more freeze-thaw cycles while other compounds thought to improve freeze-thaw stability such as glycols do not. The number and type of emulsifiers, solvents, and other components in the composition including the dispersed polymeric adhesive may influence whether or not the sugar alcohol improves the freeze-thaw stability. Thus, it is not possible to define the composition more precisely without unduly restricting the scope of the claims. Furthermore, as shown in Tables 4 to 6 in the Examples below, which report the adhesive strength of substrates bonded with Example and Control Example compositions, the adhesive strength of the polymeric adhesive may be maintained when the sugar alcohol is added.

[0061] The process according to the present disclosure for making a bonded article that includes a first substrate or a second substrate includes applying the composition of the present disclosure on at least one of the first substrate or the second substrate. The process further includes adhering the first substrate and the second substrate together using the composition. The present disclosure provides an article that comprises a first substrate and a second substrate bonded together with a composition of the present disclosure. The composition may be applied by any desired method (e.g., dipping, spraying, brushing, roll coating, bar coating). In some embodiments, where the composition is applied to both the first substrate and the second substrate. The surfaces of the first substrate and the second substrate may be any desired material. In some embodiments, at least one of the surfaces of the first substrate or the surface of the second substrate comprises at least one of metal, glass, a polymer, paper, a painted surface, a nonwoven or woven fabric, or a composite. The material of the surface of the first and second substrate may be found throughout the substrate, or the surface may include a different material from the bulk of the substrate. In some embodiments, the surface of the first substrate and / or second substrate comprises at least one of metal (e.g., steel, stainless steel, or aluminum), glass (e.g., which may be coated with indium tin oxide, for example,), a polymer (e.g., a plastic, rubber, thermoplastic elastomer, or thermoset), paper, a painted surface, or a composite. A composite material may be made from any two or more constituent materials with different physical or chemical properties. When the constituents are combined to make a composite, a material having characteristics different from the individual components is typically achieved. Some examples of useful composites include fiber-reinforced polymers (e.g., carbon fiber reinforced epoxies and glass-reinforced plastic), metal matrix compositions, and ceramic matrix composites. The surface of at least one of the first or second substrates may include polymers such as polyolefins (e.g., polypropylene, polyethylene, high density polyethylene, blends of polypropylene), polyamide 6 (PA6), acrylonitrile butadiene styrene (ABS), polycarbonate (PC), PC / ABS blends, polyvinyl chloride (PVC), polyamide (PA), polyurethane (PUR), thermoplastic elastomers (TPE), polyoxymethylene (POM), polystyrene, polyester (e.g., polyethylene terephthalate), poly(methyl) methacrylate (PMMA), and combinations thereof. The surface of at least one of the first or second substrate may also include a metal coating on such polymers. In some embodiments, at least one of the first or second substrate comprises a transparent material such as glass or a polymer (e.g., acrylic or polycarbonate).

[0062] In some embodiments, at least one of the first substrate or the second substrate has a textured surface or a porous surface. Such surfaces are common in construction and furniture making. In some embodiments, at least one of the first substrate or second substrate is a fibrous substrate or a foam substrate (e.g., a polymer foam such as polyurethane, EPDM, and polyethylene foam).

[0063] Fibrous substrates include woven or nonwoven fabric. The term “nonwoven” refers to a material having a structure of individual fibers or threads that are interlaid but not in an identifiable manner such as in a knitted fabric. Examples of nonwoven webs include spunbond webs, spunlaced webs, needle- punched webs, airlaid webs, meltblown web, and bonded carded webs. Useful nonwovens may be made of natural fibers (e.g., wood or cotton fibers), synthetic fibers (e.g., thermoplastic fibers), or a combination of natural and synthetic fibers. Examples of suitable materials for forming thermoplastic fibers include polyolefins (e.g., polyethylene, polypropylene, polybutylene, ethylene copolymers, propylene copolymers, butylene copolymers, and copolymers and blends of these polymers), polyesters, and polyamides. The fibers may also be multi-component fibers, for example, having a core of one thermoplastic material and a sheath of another thermoplastic material. Examples of woven fabrics include twill and canvas.

[0064] In some embodiments, at least one of the first substrate or the second substrate is a low surface energy substrate. The term “low surface energy substrate” is meant to refer to those substrates having a surface energy of less than 34 dynes per centimeter. Included among such materials are polypropylene, polyethylene [e.g., high density polyethylene (HDPE), low density polyethylene (LDPE), and liner low density polyethylene (LLDPE)], and blends of polypropylene (e.g., PP / EPDM, TPO). In some embodiments, at least one of the first substrate or the second substrate is a medium surface energy substrate. The term “medium surface energy substrates” is meant to refer to those substrates having a surface energy in a range from 34 to 70 dynes per centimeter, typically from 34 to 60 dynes per centimeter, and more typically from 34 to 50 dynes per centimeter. Included among such materials are polyamide 6 (PA6), acrylonitrile butadiene styrene (ABS), polycarbonate (PQ / ABS blends, PC, PVC, polyamide (PA), polyurethane (PUR), thermoplastic elastomers (TPE), polyoxymethylene (POM), polystyrene, and poly(methyl methacrylate) (PMMA). The surface energy is typically determined from contact angle measurements as described for example in ASTM D7490-08.

[0065] The composition of the present disclosure can be useful in a variety of applications. The composition of the present disclosure can also be useful for bonding dissimilar materials together. In some of these embodiments, the first substrate comprises a metal, and the second substrate comprises a rubber or plastic. In some embodiments, the first and second substrates are dissimilar plastics. The composition of the present disclosure can also be useful for foam lamination in which either the first or second substrate is a foam (e.g., a polymer foam such as polyurethane, EPDM, and polyethylene foam). The composition of the present disclosure can also be useful for packaging in which either the first or second substrate is a paper (e.g., polymer-coated paper) or paperboard. The composition of the present disclosure can be useful, for example, for installing countertops, flooring, and wall paneling in construction, assembling furniture, attaching soles in footwear manufacturing, and securing interior components in the automotive and aerospace industries.

[0066] In some embodiments, the composition of the present disclosure and / or useful for practicing the present disclosure is packaged in a spray container. Any of a variety of different spray containers may be useful for delivering the composition of the present disclosure and may be useful in the method of using a composition or the process for making a bonded article according to the present disclosure. For example, an air-assisted spray system may be useful. Examples of useful air-assisted spray systems include those obtained under the trade designation “3M Accuspray ONE Spray Gun System with Standard PPS” and “3M Accuspray Paint Spray System with PPS 2.0” from 3M Company, St. Paul, Minnesota. Thus, the spray container may be a disposable cup or a cup with a disposable liner attached to a spray gun with an atomizing head or nozzle. Spray can be assisted using compressed air, for example, at pressures in a range from 0.13 Megapascals (MPa) to 0.21 MPa. In other embodiments, an airless spray system may be useful for the composition and methods of the present disclosure. Pressure pots such as one-liter capacity pots with pressure rating up to 225 psi (1.24 MPa), obtained, for example, from Apache Stainless Steel Equipment Corporation, Beaver Dam, Wisconsin can be connected to a nylon hose obtained, for example, under the trade designation “3M Cylinder Adhesive Hose” from 3M Company, St. Paul, Minnesota. The hose can be, for example, up to 8, 7, 6, 5, 4, 3, 2, or 1 meter long. A high throughput metallic spray gun obtained, for example, under the trade designations “GunJet” and “H GunJet” from Spray Systems Co., Minnetonka, Minnesota, with a brass spray nozzle obtained, for example, under the trade designations “4001 UniJet”, “6501 UniJet”, “9501 UniJet”, “1100050 UniJet”, and “800050 UniJet” from Spray Systems Co. may conveniently attached to the hose. The canister can be pressurized with dry nitrogen gas or any desirable gas.

[0067] Some Embodiments of the Disclosure

[0068] In a first embodiment, the present disclosure provides a composition comprising water, a polymeric adhesive dispersed in the water or in the composition, and a sugar alcohol. In a second embodiment, the present disclosure provides the composition of the first embodiment, wherein the sugar alcohol improves the freeze-thaw stability of the composition relative to a comparative composition that is the same as the composition except that it includes no sugar alcohol. In a third embodiment, the present disclosure provides the composition of the first or second embodiment, wherein the composition is a spray adhesive composition.

[0069] In a fourth embodiment, the present disclosure provides the composition of any one of the first to third embodiments, wherein the polymeric adhesive comprises at least one of an acrylic polymer, polyurethane, polychloroprene, natural rubber, synthetic polyisoprene, polybutadiene, styrene / butadiene rubber, styrene / isoprene / butadiene rubber, or acrylonitrile butadiene rubber. In a fifth embodiment, the present disclosure provides the composition of the fourth embodiment, wherein the polymeric adhesive comprises at least one of an acrylic polymer, polyurethane, or poly chloroprene. In a sixth embodiment, the present disclosure provides the composition of any one of the first to fifth embodiments, further comprising a tackifier. In a seventh embodiment, the present disclosure provides the composition of the sixth embodiment, wherein the tackifier comprises at least one of a terpene resin, a rosin acid, a rosin ester, a C5 aliphatic hydrocarbon resin, a C9 aromatic resin, or a mixed aliphatic-aromatic hydrocarbon resin. In an eighth embodiment, the present disclosure provides the composition of the sixth or seventh embodiments, wherein the tackifier is present in the composition in a range from two parts to 30 parts per one hundred parts of the polymeric adhesive.

[0070] In a ninth embodiment, the present disclosure provides the composition of any one of the first to eighth embodiments, wherein the sugar alcohol comprises at least one of sorbitol, maltitol, xylitol, or erythritol. In a tenth embodiment, the present disclosure provides the composition of any one of the first to ninth embodiments, wherein the sugar alcohol comprises sorbitol. In an eleventh embodiment, the present disclosure provides the composition of any one of the first to tenth embodiments, wherein the sugar alcohol is present in the composition in an amount of at least 1.5 percent by weight or not more than ten percent by weight, based on the total weight of the composition.

[0071] In a twelfth embodiment, the present disclosure provides the composition of any one of the first to eleventh embodiments, wherein the polymeric adhesive is present in the composition in an amount of at least 40 percent by weight or not more than 60 percent by weight, based on the total weight of the composition. In a thirteenth embodiment, the present disclosure provides the composition of any one of the first to twelfth embodiments, wherein the composition is a contact adhesive. In a fourteenth embodiment, the present disclosure provides the composition of any one of the first to twelfth embodiments, wherein the composition is a pressure-sensitive adhesive. In a fifteenth embodiment, the present disclosure provides the composition of any one of the first to fourteenth embodiments, further comprising organic solvent. In a sixteenth embodiment, the present disclosure provides the composition of the fifteenth embodiment, wherein the organic solvent comprises at least one of acetone, ethanol, or methyl acetate in an amount of greater than 0.5 weight percent or at least 1, 2, 3, or 4 weight percent and up to 20, 10, or 5 weight percent, based on the total weight of the composition.

[0072] In a seventeenth embodiment, the present disclosure provides a method of improving freeze-thaw stability of a water-based adhesive composition comprising a polymeric adhesive dispersion, the method comprising including a sugar alcohol in the water-based adhesive composition. In an eighteenth embodiment, the present disclosure provides a method of improving freeze-thaw stability of a waterbased adhesive composition comprising a polymeric adhesive dispersion, the method comprising making and / or using the composition of any one of the first to sixteenth embodiments.

[0073] In a nineteenth embodiment, the present disclosure provides a use of a sugar alcohol to improve freeze-thaw stability of a water-based adhesive composition comprising a polymeric adhesive dispersion. In a twentieth embodiment, the present disclosure provides the use of the nineteenth embodiment, wherein the polymeric adhesive comprises at least one of an acrylic polymer, polyurethane, polychloroprene, natural rubber, synthetic polyisoprene, polybutadiene, styrene / butadiene rubber, styrene / isoprene / butadiene rubber, or acrylonitrile butadiene rubber. In a twenty-first embodiment, the present disclosure provides the use of the nineteenth or twentieth embodiment, wherein the polymeric adhesive comprises at least one of an acrylic polymer, polyurethane, or poly chloroprene. In a twenty- second embodiment, the present disclosure provides the use of any one of the nineteenth to twenty-first embodiments, wherein the water-based adhesive composition further comprises a tackifier. In a twenty- third embodiment, the present disclosure provides the use of the twenty-second embodiment, wherein the tackifier comprises at least one of a terpene resin, a rosin acid, a rosin ester, a C5 aliphatic hydrocarbon resin, a C9 aromatic resin, or a mixed aliphatic-aromatic hydrocarbon resin. In a twenty-fourth embodiment, the present disclosure provides the use of the twenty-second or twenty-third embodiment, wherein the tackifier is present in the water-based adhesive composition in a range from two parts to 30 parts per one hundred parts of the polymeric adhesive. In a twenty-fifth embodiment, the present disclosure provides the use of any one of the nineteenth to twenty-fourth embodiments, wherein the sugar alcohol comprises at least one of sorbitol, maltitol, xylitol, or erythritol. In a twenty-sixth embodiment, the present disclosure provides the use of any one of the nineteenth to twenty-fifth embodiments, wherein the sugar alcohol comprises sorbitol. In a twenty-seventh embodiment, the present disclosure provides the use of any one of the nineteenth to twenty-sixth embodiments, wherein the sugar alcohol is present in the water-based adhesive composition in an amount of at least 1.5 percent by weight or not more than ten percent by weight, based on the total weight of the water-based adhesive composition. In a twenty-eighth embodiment, the present disclosure provides the use of any one of the nineteenth to twenty-seventh embodiments, wherein the polymeric adhesive is present in the composition in an amount of at least 40 percent by weight or not more than 60 percent by weight, based on the total weight of the water-based adhesive composition. In a twenty-ninth embodiment, the present disclosure provides the use of any one of the nineteenth to twenty-eighth embodiments, wherein the water-based adhesive composition is a contact adhesive. In a thirtieth embodiment, the present disclosure provides the use of any one of the nineteenth to twenty-ninth embodiments, wherein the water-based adhesive composition is a pressuresensitive adhesive. In a thirty-first embodiment, the present disclosure provides the use of any one of the nineteenth to thirtieth embodiments, wherein the water-based adhesive composition further comprises organic solvent.

[0074] In a thirty-second embodiment, the present disclosure provides a method of making a bonded article comprising a first substrate and a second substrate, the method comprising applying the composition of any one of the first to sixteenth embodiments on at least one of the first substrate or the second substrate and adhering the first substrate and the second substrate together using the composition. In a thirty-third embodiment, the present disclosure provides the method of the thirty-second embodiment, wherein applying the composition comprises applying the composition to the first substrate and the second substrate. In a thirty-fourth embodiment, the present disclosure provides the method of the thirty-second or thirty-third embodiment, wherein at least one of the first substrate or the second substrate has a textured surface. In a thirty-fifth embodiment, the present disclosure provides the method of any one of the thirty-second to thirty-fourth embodiments, wherein applying comprises at least one of spraying, rolling, or brushing.

[0075] In order that this disclosure can be more fully understood, the following examples are set forth. It should be understood that these examples are for illustrative purposes only and are not to be construed as limiting this disclosure in any manner.

[0076] EXAMPLES

[0077] Unless otherwise noted, all parts, percentages, ratios, etc. in the Examples and the rest of the specification are by weight. Table 1. Materials List

[0078] Adhesive Spraying Method

[0079] All adhesives were sprayed with air assisted sprayers (obtained under the trade designation “3M Accuspray Paint Spray System with PPS 2.0” from 3M Company, Lindstrom, Minnesota). The adhesive was fed through the gun with a gravity feed cup on the back and a disposable 1.8-millimeter (mm) diameter plastic disposable nozzle (obtained under the trade designation “Accuspray Atomizing Head” from 3M Company, Lindstrom, Minnesota). The gravity feed cup was fdled with approximately 100 grams (g) of each adhesive formulation. Air pressures ranged from 10 to 30 pounds per square inch (psi) (70 to 200 kilopascals) obtained using house compressed air through a gas regulator attached to the bottom of the gun. The adhesive was sprayed from 10 to 25 centimeters (cm) away from the paper and was sprayed to deposit an approximately a wet fdm approximately 0.005 inch (127 micrometers) thick.

[0080] Overlap Shear (OLS) Test Method

[0081] Birch and beech substrates [0.250 + / - 0.125 inch x 1.0 + / - 0.25 inch x 3.0 + / - 0.25 inch (0.635 + / - 0.32 cm x 2.54 + / - 0.64 cm x 7.62 + / - 0.64 cm), obtained from Forest Product Supply, Maplewood, Minnesota) were used to analyze the bond strength of certain of the Examples. Adhesive was sprayed using the method described above along the edge of six pieces of the substrates. The samples were allowed to stand for one hour + / - 15 minutes and then were bonded at room temperature using a 1 + / - 0.125-inch (2.54 + / - 0.32-cm) overlap. Bonding was carried out using a press at 300 + / - 20 psi (2 + / - 0. 14 megapascals (MPa)) for 20 to 40 seconds. Overlap shear strength was tested on a tensile tester (from MTS Systems Corporation, Eden Prairie, Minnesota, having a minimum range of 0 to 500 pounds (227 kilograms (kg))) with samples pulled at a rate of 2 inches (5.08) cm / minute, and strength at break was recorded. The data reported in Tables 4 and 5 include an average (Avg.) of three samples.

[0082] T-Peel Test Method

[0083] Canvas strips, #10 Duct Cotton (1.5 inch x 7 inches, 3.8 cm x 17.8 cm), obtained from Big Duck Canvas, Winder, GA) were used to analyze the bond strength of certain of the Examples. Adhesive was sprayed using the method described above over a 5-inch (12.7-cm) length of the substrates. A first coat was applied followed by a ten-minute wait time. A second coat was applied followed by a ten-minute wait time. A third coat was applied followed by a five-minute wait time. Bonding was carried out by placing two coated strips of canvas together with the adhesive facing together. A hand-held, 20-pound (9- kg), 2-inch (5.08-cm) wide roller was rolled over the bonded strips five times firmly back and forth to achieve thorough contact of the adhesive surfaces. The samples were then aged for the times shown in Table 6, below. A one-inch (2.54-cm) wide cutter was used to cut the samples into one-inch (2.54-cm) wide strips. The free ends of the strips were clamped into a tensile tester (MTS Systems Corporation, Eden Prairie, Minnesota, having a 500-pound (227-kg) load cell) and peeled apart at a rate of 2 inches (5.08) cm / minute for a total of 4 inches (10 cm).

[0084] Freeze-Thaw Cycle

[0085] A 100-milliliter (mb) sample of the composition was placed in a glass or plastic container and then put into a freezer at -39 °C. The sample was left in the freezer overnight. The sample was then removed and allowed to thaw at room temperature for six hours. It was observed to determine if the solution returned to normal or if the emulsion de-stabilized and remained solid or included solid inhomogeneities. Examples (EX) 1 to 7, Control Example 1 (CE 1), and Illustrative Examples (IE) 2 to 6

[0086] The Adhesive (approximately 100 g) was combined with the sugar alcohol or other stabilizer shown in Table 2, below. The “Percentage” in Table 2 shows the weight percentage (wt%) of the sugar alcohol or other stabilizer in the composition. The sugar alcohol or other stabilizer was added to the Adhesive, which was mixed with an overhead stirrer (obtained from Gast Manufacturing, Inc., Benton Harbor, MI, model 2AM-NCC-16) with a Jiffy Mixer Co. Inc., Corona, CA, All Purpose Mixer blade with a 1.25-inch (3. 18-cm) diameter steel propeller at a low speed setting for five minutes Control Example 1 (CE 1) was the commercially obtained Adhesive. Each of EX 1 to 7, CE 1, and IE 2 to 6 was exposed to one Freeze-Thaw Cycle as described above unless otherwise indicated in Table 2. The results are shown in Table 2, below. For “compatible” compositions, a small amount of small particulates may be present.

[0087] Table 2, Formulations and Spray Rating for EX 1 to 7, CE 1, and IE 2 to 6

[0088] Examples (EX) 8 to 10 and Illustrative Examples (IE) 7 to 13

[0089] Sorbitol (2 wt. %) was added to each of the polymer dispersions shown in Table 3, below. The resulting composition was mixed as described above Examples (EX) 1 to 7, Control Example 1 (CE 1), and Illustrative Examples (IE) 2 to 6. Each of EX 8 to 10 and IE 7 to 13 was exposed to one Freeze-Thaw Cycle as described above. The results are shown in Table 3, below, in which “stable” refers to the composition returning to a stable emulsion after the Freeze / Thaw Cycle and “not stable” refers to the composition remaining as a solid mass. “Partially stable” refers to the composition returning to a stable emulsion after an extended period of time, significantly longer than a stable composition.

[0090] Table 3. Freeze / Thaw Stability of Examples 8 to 10 and Illustrative Examples IE 7 to IE 13

[0091] For adhesive testing reported in Tables 4, 5, and 6, Example 1 was freshly prepared using the method described above and divided into three portions. Overlap shear testing was carried out using CE 1 and EX 1 on birch substrates using the Overlap Shear Test method described above. The testing was carried out after 0, 1, or 3 Freeze-Thaw cycles described above on samples aged for one day or three days at room temperature (RT, 20 to 26 °C (68 to 79 °F)) after bonding. The data are shown in Table 4, below.

[0092] Table 4, OLS Testing on Birch-Birch Substrates Overlap shear testing was carried out using CE 1 and EX 1 on beech substrates using the Overlap Shear Test method described above. The testing was carried out after 0, 1, or 3 Freeze-Thaw cycles described above on samples aged for one week at RT, -37 °C, or 107 °C after bonding. The data are shown in Table 5, below.

[0093] Table 5, OLS Testing on Beech-Beech Substrates

[0094] T-peel testing was carried out using CE 1 and EX 1 on canvas substrates using the T-peel Test Method described above. The testing was carried out after 0, 1, or 3 Freeze-Thaw cycles described above on samples aged for one week at RT or three weeks at RT, -37 °C, or 82 °C after bonding. The data are shown in Table 6, below. The data are reported in pounds per inch width (PIW), Newtons / meter (N / m).

[0095] Table 6, T-Peel Testing on Canvas Substrates

[0096] This disclosure is not limited to the above-described embodiments but is to be controlled by the limitations set forth in the following claims and any equivalents thereof. This disclosure may be suitably practiced in the absence of any element not specifically disclosed herein.

Claims

What is claimed is:

1. A composition comprising: water; a polymeric adhesive dispersed in the composition; and a sugar alcohol, wherein the sugar alcohol improves the freeze-thaw stability of the composition relative to a comparative composition that is the same as the composition except that it includes no sugar alcohol.

2. The composition of claim 1, wherein the polymeric adhesive comprises at least one of an acrylic polymer, polyurethane, polychloroprene, natural rubber, synthetic polyisoprene, polybutadiene, styrene / butadiene rubber, styrene / isoprene / butadiene rubber, or acrylonitrile butadiene rubber.

3. The composition of claim 1 or 2, wherein the polymeric adhesive comprises at least one of an acrylic polymer, polyurethane, or poly chloroprene.

4. The composition of any one of claims 1 to 3, further comprising a tackifier, wherein the tackifier comprises at least one of a terpene resin, a rosin acid, a rosin ester, a C5 aliphatic hydrocarbon resin, a C9 aromatic resin, or a mixed aliphatic -aromatic hydrocarbon resin.

5. The composition of any one of claims 1 to 4, wherein the sugar alcohol comprises at least one of sorbitol, maltitol, xylitol, or erythritol.

6. The composition of claim 5, wherein the sugar alcohol comprises sorbitol.

7. The composition of any one of claims 1 to 6, wherein the sugar alcohol is present in the composition in an amount of at least 1.5 percent by weight or not more than ten percent by weight, based on the total weight of the composition.

8. The composition of any one of claims 1 to 7, wherein the polymeric adhesive is present in the composition in an amount of at least 40 percent by weight or not more than 60 percent by weight, based on the total weight of the composition.

9. The composition of any one of claims 1 to 8, wherein the composition is a contact adhesive.

10. The composition of any one of claims 1 to 8, wherein the composition is a pressure-sensitive adhesive.

11. A method of making a bonded article comprising a first substrate and a second substrate, the method comprising: applying the composition of any one of claims 1 to 10 on at least one of the first substrate or the second substrate; and adhering the first substrate and the second substrate together using the composition.

12. The method of claim 11, wherein applying comprises applying the composition to the first substrate and the second substrate.

13. The method of claim 11 or 12, wherein applying comprises at least one of spraying, rolling, or brushing.

14. A method of improving freeze-thaw stability of a water-based adhesive composition comprising a polymeric adhesive dispersion, the method comprising including a sugar alcohol in the water-based adhesive composition.

15. Use of a sugar alcohol to improve freeze-thaw stability of a water-based adhesive composition comprising a polymeric adhesive dispersion.

Images