Crosslinked pretreatment compositions for metal substrates and methods of making the same

Abstract

Described herein are pretreated metal product and methods of pretreating metal products. Pretreated metal products include an aluminum alloy product having a surface, and a crosslinked graft copolymer pretreatment composition bonded to the surface of the aluminum alloy product. The crosslinked graft copolymer pretreatment composition includes a polymer backbone and at least one surface binding or bonding moiety attached to the polymer backbone configured to bind or bond the polymer backbone to a first surface of a metal product, and at least one functional moiety attached to the polymer backbone and configured to provide at least a first surface functionalization to the first surface of the metal product. The crosslinked graft copolymer pretreatment composition includes where the at least one functional moiety and / or the at least one surface binding or bonding moiety, are directly crosslinked to a further functional moiety and / or surface binding or bonding moiety.

Description

Attorney Docket No. 108050-1530445CROSSLINKED PRETREATMENT COMPOSITIONS FOR METAL SUBSTRATES AND METHODS OF MAKING THE SAMECROSS-REFERENCE TO RELATED APPLICATION

[0001] This application claims priority to and the benefit of U.S. Provisional Patent Application No. 63 / 721,685, filed November 18, 2024, and U.S. Provisional Patent Application No. 63 / 757,152, filed February 11, 2025, which are hereby incorporated by reference in their entireties for all intents and purposes.FIELD

[0002] The present disclosure relates to the fields of materials science, materials chemistry, surface science, metal manufacturing, aluminum alloys, and aluminum manufacturing. Compositions and methods are disclosed herein that can be employed in automotive, transportation, electronics, industrial, and other applications. The compositions and methods disclosed herein are particularly suitable for use in motor vehicles.BACKGROUND

[0003] Aluminum alloys are often used in environments that may incur deleterious effects to the surface, or at least a portion of the surface, of the aluminum alloy. As such, the aluminum alloys may be subject to corrosion, poor bond durability, difficulty separating stacked aluminum alloy products, uneven coating, and poor weldability and / or weld durability. Many pretreatment compositions provide functionality to address a single surface-related issue. Thus, a pretreatment composition incorporating a plurality of surface functionalizations is desirable.SUMMARY

[0004] Covered embodiments of the invention are defined by the claims, not this summary. This summary is a high-level overview of various aspects of the invention and introduces some of the concepts that are further described in the Detailed Description section below. This summary is not intended to identify key or essential features of the claimed subject matter, nor is it intended to be used in isolation to determine the scope of the claimed subject matter. The subject matter should be understood by reference to appropriate portions of the entire specification, any or all drawings, and each claim.Attorney Docket No. 108050-1530445

[0005] The present technology is generally directed to pretreated metal products.Products include an aluminum alloy product having a surface and a crosslinked graft copolymer pretreatment composition bonded to the surface of the aluminum alloy product. Products include where the crosslinked graft copolymer pretreatment composition has a polymer backbone, at least one surface binding or bonding moiety attached to the polymer backbone and configured to bind or bond the polymer backbone to a first surface of a metal product, and at least one functional moiety attached to the polymer backbone and configured to provide at least a first surface functionalization to the first surface of the metal product. Products include where the at least one functional moiety, the at least one surface binding or bonding moiety, or both the at least one functional moiety and the at least one surface binding or bonding moiety are directly crosslinked to a further one of the at least one functional moiety or at least one surface binding or bonding moiety.

[0006] In embodiments, the crosslinked graft copolymer pretreatment composition contains less than 1 wt.% external crosslinking agents, based upon the weight of the crosslinked graft copolymer pretreatment composition. In more embodiments, the crosslinked graft copolymer pretreatment composition contains less than 0.1 wt.% external crosslinking agents, based upon the weight of the crosslinked graft copolymer pretreatment composition. Furthermore, in embodiments, the at least one surface binding or bonding moiety comprises a phosphonate group, a phosphate group, a phosphoryl group, a carboxyl group, a catechol group, or a trialkoxysilyl group. Additionally or alternatively, in embodiments, the at least one surface binding or bonding moiety is crosslinked to the further one of the at least one surface binding or bonding moiety. Moreover, in embodiments, the direct crosslinkage includes an anhydride bond between two of the at least one surface binding or bonding moiety. Embodiments include where the polymer backbone is poly(methyl methacrylate), poly(ethyl methacrylate), poly(ethyl acrylate), polyacrylonitrile, polyethylene, polypropylene, polystyrene, poly(vinyl chloride), poly(vinyl acetate), poly(vinyl alcohol), polybutadiene, polyisoprene, polychloroprene, or any combination thereof. In yet more embodiments, the at least one functional moiety includes a polymer side chain that provides a lubricating function. In embodiments, the at least one functional moiety includes a humectant. In further embodiments, the at least one functional moiety includes a weld promoter. Moreover, in embodiments, the at least one functional moiety includes a corrosion inhibitor. Embodiments include at least one second functional moiety, where the at least one second functional moiety includes an adhesion promoter, a polymer side chain that provides a lubricating function, aAttorney Docket No. 108050-1530445humectant, a weld promoter, or a corrosion inhibitor. In embodiments, the pretreated metal product exhibits a sliding distance of greater than 50 cm at 300 mN, as measured using a nanotribometer.

[0007] The present technology is also generally directed to methods of pretreating at least a portion of a metal surface. Methods include applying a graft copolymer pretreatment composition to at least the portion of the metal surface. Methods include where the graft copolymer pretreatment composition has a polymer backbone, at least one surface binding or bonding moiety attached to the polymer backbone and configured to bind or bond the polymer backbone to a first surface of a metal product, and at least one functional moiety attached to the polymer backbone and configured to provide at least a first surface functionalization to the first surface of the metal product. Methods include crosslinking the at least one functional moiety, the at least one surface binding or bonding moiety, or both the at least one functional moiety and the at least one surface binding or bonding moiety directly to a further one of the at least one functional moiety or at least one surface binding or bonding moiety.

[0008] In embodiments, crosslinking includes drying the graft copolymer pretreatment composition at a temperature of greater than or about 80 °C for greater than or about 5 minutes. In more embodiments, crosslinking includes drying the graft copolymer pretreatment composition at a temperature of greater than or about 100 °C for greater than or about 2 minutes. Furthermore, in embodiments, crosslinking includes curing the graft copolymer pretreatment composition at a temperature of about 60 °C to about 250 °C for less than or about 20 seconds. Embodiments include where the graft copolymer pretreatment composition exhibits a residual thickness of greater than 200 nm. In embodiments, the graft copolymer pretreatment composition includes a residual thickness of greater than 250 nm.

[0009] The present technology is also generally directed to pretreated metal products formed according to any of the methods discussed herein.

[0010] Other objects and advantages will be apparent from the following detailed description of non-limiting examples and formulae.BRIEF DESCRIPTION OF THE DRAWINGS

[0011] FIGS. 1A-1C provide schematic illustrations of a coated metal product according to aspects of the present technology.Attorney Docket No. 108050-1530445

[0012] FIG. 2 is a schematic showing a crosslinked graft copolymer layer applied to an substrate surface forming according to examples described herein.

[0013] FIG. 3 shows a graph of film thickness before and after rinsing, according to examples of the present technology.

[0014] FIG. 4 shows a graph of relative strength over time according to examples of the present technology.

[0015] FIG. 5 shows where fractures occurred during salt spray testing according to examples of the present technology.DETAILED DESCRIPTION

[0016] Provided herein are pretreated metal substrates, and methods of pretreating such substrates with crosslinked graft copolymer pretreatment compositions that impart surface functionalization to metals, including alloys such as aluminum alloys. Pretreatment, as used herein, refers to a surface modification, typically in the form of a solution or suspension that is applied to a surface and converted to a layer through physical and / or chemical reactions. The pretreatment layer is applied before the metals are subjected to processing or use (e.g., before a forming process, before placing the metals into service in an outdoor environment, or the like). The pretreatment layer imparts characteristics and performance qualities that can be significantly different from the bulk of the metal or the metal surface. For example, the crosslinked graft copolymer pretreatment compositions and methods described herein provide an improved coefficient of friction to the surface of the substrate and improved formability of the substrate. In addition, the disclosed coatings and methods improve the corrosion resistance of metals (e.g., aluminum and aluminum alloys) when put in service in corrosive conditions, e.g., in automotive structural parts and / or automotive body parts.

[0017] Previously, it was believed that external crosslinking agents or precursors were necessary to provide robust crosslinking to the pretreatment compositions. Namely, the pretreatment compositions discussed herein may be soluble in one or more solvents, such as water, prior to crosslinking. This allows the pretreatment composition to be easily applied as a solution. However, high solubility is problematic, as it allows for the pretreatment composition to be easily and inadvertently removed during further processing of the substrate. Thus, prior attempts to utilize such multi-functional surface treatments including external crosslinking agents, such as zirconium, to crosslink the pretreatment composition, allowing the formed film to be stable when exposed to various solvents. However, such crosslinking agents may hinder the recyclability of the substrate and may impact theAttorney Docket No. 108050-1530445environmental impact of the film. Furthermore, the addition of crosslinking agents greatly increase the waste (decrease the efficiency) of the coating process, as a large amount of water is needed to form a solution of the crosslinking agent and also requires an additional process step, increasing process time. Therefore, it would be beneficial to provide a crosslinked pretreatment composition and method of crosslinking such compositions that do not require additional crosslinking agents.

[0018] Thus, the present technology has surprisingly found that by carefully selecting one or more functional groups and / or surface bonding or binding agents as well as controlling a drying temperature and time, a crosslinked graft copolymer pretreatment composition is provided without the inclusion of external crosslinking agents or precursors. Namely, by carefully controlling the drying temperature and time of the graft copolymer pretreatment composition, reactive groups on one or more functional moieties and / or surface binding or bonding moieties may form a direct crosslinkage to a further functional moiety or surface binding or bonding moiety. Therefore, the crosslinking bond may be considered to be generally free of, or completely free of, external crosslinking agents or precursors. This was surprising, as it was previously found that graft copolymer pretreatment layers formed from pretreatment compositions that lacked external crosslinking agents failed to provide a stabilized film, and therefore lacked the necessary stability to survive rinsing, as exhibited by film thickness testing and / or sliding distance via nanotribology.

[0019] Nonetheless, the crosslinked graft copolymer pretreatment compositions and methods described herein impart an improved coefficient of friction to the metal surfaces as compared to non-pretreated metal surfaces. In certain aspects, the graft copolymer pretreatment compositions and methods described herein provide lubrication to the metal surfaces as compared to non-pretreated metal surfaces. In some examples, the graft copolymer pretreatment compositions and methods described herein provide improved coating performance (e.g., enhanced wettability) to the alloy surfaces as compared to nonpretreated metal surfaces. In certain cases, the graft copolymer pretreatment compositions and methods described herein improve the weldability and / or weld durability of the metal surfaces as compared to non-pretreated metal surfaces. In certain aspects, the graft copolymer pretreatment compositions and methods described herein provide a multi-functional surface coating imparting at least one of lubrication, corrosion resistance, enhanced adhesion performance, improved coating performance, and / or improved weldability and / or weld durability.Attorney Docket No. 108050-1530445Definitions and Descriptions:

[0020] The terms “invention,” “the invention,” “this invention,” and “the present invention” used herein are intended to refer broadly to all of the subject matter of this patent application and the claims below. Statements containing these terms should be understood not to limit the subject matter described herein or to limit the meaning or scope of the patent claims below.

[0021] In this description, reference is made to alloys identified by aluminum industry designations, such as “series” or “6xxx.” For an understanding of the number designation system most commonly used in naming and identifying aluminum and its alloys, see “International Alloy Designations and Chemical Composition Limits for Wrought Aluminum and Wrought Aluminum Alloys” or “Registration Record of Aluminum Association Alloy Designations and Chemical Compositions Limits for Aluminum Alloys in the Form of Castings and Ingot,” both published by The Aluminum Association.

[0022] As used herein, the meaning of “a,” “an,” or “the” includes singular and plural references unless the context clearly dictates otherwise.

[0023] As used herein, a plate generally has a thickness of greater than about 15 mm. For example, a plate may refer to an aluminum product having a thickness of greater than about 15 mm, greater than about 20 mm, greater than about 25 mm, greater than about 30 mm, greater than about 35 mm, greater than about 40 mm, greater than about 45 mm, greater than about 50 mm, greater than about 100 mm, or up to about 200 mm.

[0024] As used herein, a shate (also referred to as a sheet plate) generally has a thickness of from about 4 mm to about 15 mm. For example, a shate may have a thickness of about 4 mm, about 5 mm, about 6 mm, about 7 mm, about 8 mm, about 9 mm, about 10 mm, about 11 mm, about 12 mm, about 13 mm, about 14 mm, or about 15 mm.

[0025] As used herein, a sheet generally refers to an aluminum product having a thickness of less than about 4 mm. For example, a sheet may have a thickness of less than about 4 mm, less than about 3 mm, less than about 2 mm, less than about 1 mm, less than about 0.5 mm, less than about 0.3 mm, or less than about 0.1 mm.

[0026] Reference is made in this application to alloy temper or condition. For an understanding of the alloy temper descriptions most commonly used, see “American National Standards (ANSI) H35 on Alloy and Temper Designation Systems.” An F condition or temper refers to an aluminum alloy as fabricated. An O condition or temper refers to an aluminum alloy after annealing. An Hxx condition or temper, also referred to herein as an HAttorney Docket No. 108050-1530445temper, refers to a non-heat treatable aluminum alloy after cold rolling with or without thermal treatment (e.g., annealing). Suitable H tempers include Hxl, Hx2, Hx3 Hx4, Hx5, Hx6, Hx7, Hx8, or Hx9 tempers. A T1 condition or temper refers to an aluminum alloy cooled from hot working and naturally aged (e.g., at room temperature). A T2 condition or temper refers to an aluminum alloy cooled from hot working, cold worked and naturally aged. A T3 condition or temper refers to an aluminum alloy solution heat treated, cold worked, and naturally aged. A T4 condition or temper refers to an aluminum alloy solution heat treated and naturally aged. A T5 condition or temper refers to an aluminum alloy cooled from hot working and artificially aged (at elevated temperatures). A T6x condition or temper refers to an aluminum alloy solution heat treated and artificially aged. A T7 condition or temper refers to an aluminum alloy solution heat treated and artificially overaged. A T8x condition or temper refers to an aluminum alloy solution heat treated, cold worked, and artificially aged. A T9 condition or temper refers to an aluminum alloy solution heat treated, artificially aged, and cold worked. A W condition or temper refers to an aluminum alloy after solution heat treatment.

[0027] As used herein, the meaning of “room temperature” can include a temperature of from about 15 °C to about 30 °C, for example about 15 °C, about 16 °C, about 17 °C, about 18 °C, about 19 °C, about 20 °C, about 21 °C, about 22 °C, about 23 °C, about 24 °C, about 25 °C, about 26 °C, about 27 °C, about 28 °C, about 29 °C, or about 30 °C.

[0028] All ranges disclosed herein are to be understood to encompass any and all endpoints with any and all subranges subsumed therein. For example, a stated range of “1 to 10” should be considered to include any and all subranges between (and inclusive of) the minimum value of 1 and the maximum value of 10; that is, all subranges beginning with a minimum value of 1 or more, e.g. 1 to 6.1, and ending with a maximum value of 10 or less, e.g., 5.5 to 10.

[0029] As used herein, terms such as “cast metal product,” “cast product,” “cast aluminum alloy product,” and the like are interchangeable and refer to a product produced by direct chill casting (including direct chill co-casting) or semi-continuous casting, continuous casting (including, for example, by use of a twin belt caster, a twin roll caster, a twin block caster, or any other continuous caster), electromagnetic casting, hot top casting, or any other casting method.

[0030] The term “and / or” when used in a list of two or more items, means that any one of the listed items can be employed by itself or in combination with any one or more of theAttorney Docket No. 108050-1530445listed items. For example, the expression “A and / or B” is intended to mean either or both of A and B, i.e., A alone, B alone, or A and B in combination. The expression “A, B and / or C” is intended to mean A alone, B alone, C alone, A and B in combination, A and C in combination, B and C in combination or A, B, and C in combination.

[0031] As used herein, the term “surface functionalization” refers to methods and compositions for altering the surface properties and / or characteristics of a material to achieve desired surface properties including, but not limited to, corrosion resistance, enhanced adhesion, uniform wetting, accelerated drying, any other desired surface property or characteristic, or any combination thereof.

[0032] As used herein, an acrylic class chain polymer structure is formed by polymerizing functionalized and / or unfunctionalized acrylate monomers (e.g., monomers having the structure -CH2=CHCOOR) into a chain polymer; a methacrylic class chain polymer structure is formed by polymerizing functionalized and / or unfunctionalized methacrylate monomers (e.g., monomers having the structure -CH2=CCH3COOR) into a chain polymer; a vinyl class chain polymer structure is formed by polymerizing functionalized and / or unfunctionalized vinyl monomers (e.g., monomers having the structure -CH2=CH — R) into a chain polymer; a diene class chain polymer structure is formed by polymerizing functionalized and / or unfunctionalized diene monomers (e.g., monomers having the structure -CH2=CR — CR’=CH2) into a chain polymer; and a vinylidene class chain polymer structure is formed by polymerizing functionalized and / or unfunctionalized vinylidene monomers (e.g., monomers having the structure -C=CRR’) into a chain polymer. In the above examples, R and R’ are each independently selected from hydrogen, functionalized or unfunctionalized alkyl substituents, functionalized or unfunctionalized alkenyl substituents, functionalized or unfunctionalized alkynyl substituents, any suitable substituent as described herein, or any suitable polymer side chain.

[0033] As used herein, the terms alkyl, alkenyl, and alkynyl include straight- and branched-chain monovalent substituents. Examples include methyl, ethyl, isobutyl, 3-butynyl, and the like. Ranges of these groups useful with the compositions and methods described herein include C1-C20 alkyl, C2-C20 alkenyl, and C2-C20 alkynyl. Additional ranges of these groups useful with the compositions and methods described herein include C1-C12 alkyl, C2-C12 alkenyl, C2-C12 alkynyl, Ci-Ce alkyl, C2-C6 alkenyl, C2-C6 alkynyl, C1-C4 alkyl, C2-C4 alkenyl, and C2-C4 alkynyl.Attorney Docket No. 108050-1530445

[0034] Heteroalkyl, heteroalkenyl, and heteroalkynyl are defined similarly as alkyl, alkenyl, and alkynyl, but can contain O, S, or N heteroatoms or combinations thereof within the backbone. Ranges of these groups useful with the compositions and methods described herein include C1-C20 heteroalkyl, C2-C20 heteroalkenyl, and C2-C20 heteroalkynyl. Additional ranges of these groups useful with the compositions and methods described herein include C1-C12 heteroalkyl, C2-C12 heteroalkenyl, C2-C12 heteroalkynyl, Ci-Ce heteroalkyl, C2-C6 heteroalkenyl, C2-C6 heteroalkynyl, C1-C4 heteroalkyl, C2-C4 heteroalkenyl, and C2-C4 heteroalkynyl.

[0035] The terms cycloalkyl, cycloalkenyl, and cycloalkynyl include cyclic alkyl groups having a single cyclic ring or multiple condensed rings. Examples include cyclohexyl, cyclopentylethyl, and adamantanyl. Ranges of these groups useful with the compositions and methods described herein include C3-C20 cycloalkyl, C3-C20 cycloalkenyl, and C3-C20 cycloalkynyl. Additional ranges of these groups useful with the compositions and methods described herein include C5-C12 cycloalkyl, C5-C12 cycloalkenyl, C5-C12 cycloalkynyl, Cs-Ce cycloalkyl, Cs-Ce cycloalkenyl, and Cs-Ce cycloalkynyl.

[0036] The terms heterocycloalkyl, heterocycloalkenyl, and heterocycloalkynyl are defined similarly as cycloalkyl, cycloalkenyl, and cycloalkynyl, but can contain O, S, or N heteroatoms or combinations thereof within the cyclic backbone. Ranges of these groups useful with the compositions and methods described herein include C3-C20 heterocycloalkyl, C3-C20 heterocycloalkenyl, and C3-C20 heterocycloalkynyl. Additional ranges of these groups useful with the compositions and methods described herein include C5-C12 heterocycloalkyl, C5-C12 heterocycloalkenyl, C5-C12 heterocycloalkynyl, Cs-Ce heterocycloalkyl, Cs-Ce heterocycloalkenyl, and Cs-Ce heterocycloalkynyl.

[0037] The term hydroxyl as used herein is represented by the formula — OH.

[0038] Aryl molecules include, for example, cyclic hydrocarbons that incorporate one or more planar sets of, typically, six carbon atoms that are connected by delocalized electrons numbering the same as if they consisted of alternating single and double covalent bonds. An example of an aryl molecule is benzene. Heteroaryl molecules include substitutions along their main cyclic chain of atoms such as O, N, or S. Examples of heteroaryl molecules include furan, pyrrole, thiophene, imidazole, oxazole, pyridine, and pyrazine. Aryl and heteroaryl molecules can also include additional fused rings, for example, benzofuran, indole, benzothiophene, naphthalene, anthracene, and quinoline. The aryl and heteroaryl molecules can be attached at any position on the ring, unless otherwise noted.Attorney Docket No. 108050-1530445

[0039] The term alkoxy as used herein is an alkyl group attached to the remainder of the molecule via an oxygen atom. The term aryloxy as used herein is an aryl group attached to the remainder of the molecule via an oxygen atom. Likewise, the terms alkenyloxy, alkynyloxy, heteroalkyloxy, heteroalkenyloxy, heteroalkynyloxy, heteroaryloxy, cycloalkyloxy, and heterocycloalkyloxy as used herein are an alkenyloxy, alkynyloxy, heteroalkyloxy, heteroalkenyloxy, heteroalkynyloxy, heteroaryloxy, cycloalkyloxy, and heterocycloalkyloxy group, respectively, attached to the remainder of the molecule via an oxygen atom.

[0040] The alkoxy, aryloxy, amino, alkyl, alkenyl, alkynyl, aryl, heteroalkyl, heteroalkenyl, heteroalkynyl, heteroaryl, cycloalkyl, or heterocycloalkyl molecules used herein can be substituted or unsubstituted. As used herein, the term substituted includes the addition of an alkoxy, aryloxy, amino, alkyl, alkenyl, alkynyl, aryl, heteroalkyl, heteroalkenyl, heteroalkynyl, heteroaryl, cycloalkyl, or heterocycloalkyl group to a position attached to the main chain of the alkoxy, aryloxy, amino, alkyl, alkenyl, alkynyl, aryl, heteroalkyl, heteroalkenyl, heteroalkynyl, heteroaryl, cycloalkyl, or heterocycloalkyl, e.g., the replacement of a hydrogen by one of these molecules. Examples of substitution groups include, but are not limited to, hydroxy, halide (e.g., fluoride, chloride, bromide, or iodide), and carboxyl groups. Conversely, as used herein, the term unsubstituted indicates the alkoxy, aryloxy, amino, alkyl, alkenyl, alkynyl, aryl, heteroalkyl, heteroalkenyl, heteroalkynyl, heteroaryl, cycloalkyl, or heterocycloalkyl has a full complement of hydrogens, i.e., commensurate with its saturation level, with no substitutions, e.g., linear decane (-(CH2)9-CH3).

[0041] The structures depicted herein include all enantiomeric, diastereomeric, and geometric (or conformational) forms of the structure; for example, the R and S configurations for each asymmetric center, cis and trans isomers, (Z) and (E) double bond isomers, and (Z) and (E) conformational isomers.

[0042] As used herein, the term polymer is inclusive of homopolymers and copolymers. Homopolymer refers to a polymer derived from a single polymerizable monomer. Copolymer refers to a polymer derived from two or more polymerizable monomers.

[0043] As used herein, a crosslinked polymer is defined by the presence of inter-chain links connecting two or more individual polymer chains. A crosslinked polymer can be permanently or temporarily crosslinked.Attorney Docket No. 108050-1530445

[0044] As used herein, a crosslinking agent can connect two or more individual chains via a crosslinking reaction between the two mor more individual chains.Pretreatment Compositions:

[0045] Described herein are graft copolymer pretreatment compositions suitable for crosslinking, that, in some examples, are bonded to at least a portion of a surface of a metal product, including a metal alloy product, for example, an aluminum alloy product. While aluminum alloy products are described throughout the text, the methods and products apply to any metal. In some examples, the metal product may be aluminum, an aluminum alloy, magnesium, a magnesium-based material, titanium, a titanium-based material, copper, a copper-based material, steel, a steel-based material, bronze, a bronze-based material, brass, a brass-based material, a composite, a sheet used in composites, or any other suitable metal or combination of materials. The metal product may include monolithic materials, as well as non-monolithic materials such as roll-bonded materials, clad materials, composite materials, or various other materials. In some examples, the metal product is a metal coil, a metal strip, a metal plate, a metal sheet, a metal billet, a metal ingot, or the like.

[0046] In some non-limiting examples, the graft copolymer pretreatment compositions described herein include a polymer backbone, a pendant moiety that can bind or bond the graft copolymer pretreatment composition to a metal surface (i.e., the surface binding or bonding moiety), and at least one functional pendant moiety that can impart a functional pretreatment characteristic to the metal surface (i.e., a functional moiety).Polymer Backbone

[0047] In some cases, the polymer backbone is an acrylic class chain polymer structure, a methacrylic class chain polymer structure, a vinyl class chain polymer structure, a diene class chain polymer structure, a vinylidene class chain polymer structure, or any combination thereof. For example, the polymer backbone can be poly(methacrylic acid), poly(methyl methacrylate), poly(ethyl methacrylate), poly(acrylic acid), poly(methyl acrylate), poly(ethyl acrylate), poly(butyl acrylate), polyacrylonitrile, polyethylene, polypropylene, polystyrene, poly(vinyl chloride), poly(vinyl acetate), poly(vinyl alcohol), polybutadiene, polyisoprene, polychloroprene, or any combination thereof.

[0048] In some cases, the chain polymer structure can be prepared from a vinyl -containing monomer to form a backbone according to Formula I below:Attorney Docket No. 108050-1530445Formula IIn Formula I, n is in a range of from 10 to 1000 (e.g., from 15 to 750, from 20 to 700, from 25 to 650, from 50 to 600, from 100 to 500, or from 200 to 400). Also in Formula I, R includes a functional moiety that can impart a functional pretreatment characteristic to the metal surface (e.g., the functional moiety can be a corrosion inhibitor, an adhesion promoter, a polymer side chain that provides a lubricating function (i.e., a lubricant and / or a lubricant functional moiety), a humectant, and / or a weld promoter as described below). Optionally, the functional moiety can include an ethylene oxide group, a phosphonic acid group, a phosphoric acid group, a hydroxyethyl group, a 2-methacryloyloxyethyl group, a 2,2,2-trifluoroethyl group, or a butyl group. Further functional groups that can be used in the graft copolymer pretreatment compositions are detailed below. In some cases, the functional moiety is attached to the backbone through a linker group, such as a substituted or unsubstituted alkyl, a substituted or unsubstituted alkenyl, or a substituted or unsubstituted carbonyl (e.g., a substituted or unsubstituted carboxyl).

[0049] In some cases, the chain polymer structure can be prepared from a diene-containing monomer to form a backbone according to Formula II below:Formula IIIn Formula II, n is in a range of from 10 to 1000 (e.g., from 15 to 750, from 20 to 700, from 25 to 650, from 50 to 600, from 100 to 500, or from 200 to 400). Also in Formula II, R includes a functional moiety that can impart a functional pretreatment characteristic to the metal surface (e.g., the functional moiety can be a corrosion inhibitor, an adhesion promoter, a lubricant, a humectant, and / or a weld promoter as described below). Optionally, the functional moiety can include an ethylene oxide group, a phosphonic acid group, a phosphoric acid group, a hydroxyethyl group, a 2-methacryloyloxyethyl group, a 2,2,2-trifluoroethyl group, or a butyl group. Further functional groups that can be used in the graft copolymer pretreatment compositions are detailed below. In some cases, the functional moiety is attached to the backbone through a linker group, such as a substituted or unsubstituted alkyl, a substituted or unsubstituted alkenyl, or a substituted or unsubstitutedAttorney Docket No. 108050-1530445carbonyl (e.g., a substituted or unsubstituted carboxyl). In some examples, one or more double bonds present in Formula II can be in an E-configuration. In some examples, one or more double bonds present in Formula II can be in a Z-configuration.

[0050] In some cases, the chain polymer structure can be prepared from an acrylic- or a methacrylic-containing monomer to form a backbone according to Formula III below:Formula IIIIn Formula III, n is in a range of from 10 to 1000 (e.g., from 15 to 750, from 20 to 700, from 25 to 650, from 50 to 600, from 100 to 500, or from 200 to 400). Also in Formula III, R includes a functional moiety that can impart a functional pretreatment characteristic to the metal surface (e.g., the functional moiety can be a corrosion inhibitor, an adhesion promoter, a lubricant, a humectant, and / or a weld promoter as described below). Optionally, the functional moiety can include an ethylene oxide group, a phosphonic acid group, a phosphoric acid group, a hydroxyethyl group, a 2-methacryloyloxyethyl group, a 2,2,2-trifluoroethyl group, or a butyl group. Further functional groups that can be used in the graft copolymer pretreatment compositions are detailed below. In some cases, the functional moiety is attached to the backbone through a linker group, such as a substituted or unsubstituted alkyl, a substituted or unsubstituted alkenyl, or a substituted or unsubstituted carbonyl (e.g., a substituted or unsubstituted carboxyl). Further in Formula III, X is hydrogen when the polymer is prepared from an acrylic-containing monomer. In Formula III, X is methyl when the polymer is prepared from a methacrylic-containing monomer.Surface Binding or Bonding Moiety

[0051] As further described below, the surface binding or bonding moiety can bind or bond the chain polymer structure described herein to the metal surface by a covalent bond, an ionic bond, a hydrogen bond, a dipolar interaction, or any combination thereof. In some aspects, the surface binding or bonding moiety is a reactive group or groups that can react with and become covalently bonded to the metal surface. Example reactive groups can include, for example, phosphorus-containing moieties (e.g., phosphoric acids, phosphonicAttorney Docket No. 108050-1530445acids), silicon-containing moi eties (e.g., siloxanes and silanes), sulfur-containing moi eties (e.g., sulfuric acids, sulfonic acids), carboxylic acids (e.g., acrylic acids, methacrylic acids), or metal hydrides, among others. In some cases, the reactive group can optionally be substituted with substituents that can provide additional covalent bonding (e.g., additional hydroxyl groups). For example, the hydroxyl functionalities of the phosphorus- or silicon-containing moieties can react at the surface of the metal product, such as directly with metal atoms of the metal product, to form a metal-oxygen-phosphorus bond or a metal-oxygen-silicon bond in a condensation reaction. Optionally, the reactive groups of the graft copolymer pretreatment composition can react with an oxide surface layer of the metal product.

[0052] However, as will be discussed in greater detail below, at least one of the surface binding or bonding moiety and the at least one functional moiety include one or more functional groups suitable for crosslinking with a further surface binding or bonding moiety and / or functional moiety. For instance, in embodiments, at least one at least one of the surface binding or bonding moiety and the at least one functional moiety may include a functional group that may form an anhydride or ester linkage. In embodiments, the at least one of the surface binding or bonding moiety and the at least one functional moiety include a phosphonate group, a phosphate group, a phosphoryl group, a carboxyl group, a catechol group, or a trialkoxysilyl group, as well as one or more functional groups that form one or more bonds with an further surface binding or bonding moiety and / or functional moiety, such as during a condensation reaction. For instance, in embodiments, the at least one of the surface binding or bonding moiety and the at least one functional moiety include a hydroxyl group, forming an anhydride bond with a hydroxyl group of a further surface binding or bonding moiety and / or functional moiety. In embodiments, the binding moiety may contain the one or more functional groups suitable for crosslinking with a further surface binding or bonding moiety and / or functional moiety. In embodiments, the further surface binding or bonding moiety and / or functional moiety may also be a surface binding or bonding moiety, such that a functional group of the surface binding or bonding moiety is bonded to a further surface binding or bonding moiety.

[0053] In embodiments, it should be clear that no additional crosslinking precursors or external crosslinking agents may be necessary and may be included or excluded. Instead, under tailored heating and / or drying conditions discussed below, existing reactive groups on the surface binding or bonding moiety may react with, and become bonded, such asAttorney Docket No. 108050-1530445covalently bonded, to a further surface binding or bonding moiety. For example, the hydroxyl functionalities of the phosphorus- or silicon-containing moieties can react with a further hydroxyl functionality of a phosphorus- or silicon-containing moiety to form a phosphorusoxygen-phosphorous bond or silicon-oxygen-silicon bond. However, as discussed above, other reactive groups and bonds are contemplated herein.Functional Moieties

[0054] In certain aspects, the graft copolymer pretreatment compositions described herein further include at least one functional moiety to impart a functionalization to the metal surface. For example, the at least one functional moiety can be an adhesion promoter, an adhesive, a lubricant, a humectant, a corrosion inhibitor, a weld promoter, or any combination thereof. In some examples, the graft copolymer pretreatment compositions described herein include an adhesion promoter functional moiety. In certain examples, the adhesion promoter functional moiety can be a hydroxyl group, an amine group, a carboxylic acid group, an amide group, a thiol group, an epoxide group, a vinyl group, a diol group, or combinations thereof.

[0055] In some examples, the graft copolymer pretreatment compositions described herein include a lubricant functional moiety. For example, the lubricant functional moiety can be polyethylene glycol, polytetrahydrofuran, polyisobutene, polybutadiene, polyisoprene, polysiloxane, or any combination thereof. Incorporating a lubricant functional moiety can disrupt the surface tension between metal products that are stacked together, thus improving de-stacking capability. Additionally, incorporating a lubricant functional moiety can reduce and / or stabilize frictional forces between, for example, a forming die and a sheet metal surface, leading to better formability with reduced cracking or splitting, reduced wrinkling and tear-off rates, higher processing speeds, reduced galling, enhanced tool life, and improved surface quality in formed metal parts.

[0056] In some examples, the graft copolymer pretreatment compositions described herein can include a humectant functional moiety. For example, the humectant functional moiety can be polypropylene glycol, hexylene glycol, butylene glycol, lactic acid, sodium hexametaphosphate, glycerol, sorbitol, xylitol, maltitol, urea, or any combination thereof. Incorporating a humectant functional moiety can disrupt the surface tension between the metal surface and certain aqueous solutions (e.g., additional pretreatment compositions, coatings, cleaning solutions, and the like, or any combination thereof). Additionally,Attorney Docket No. 108050-1530445incorporating a humectant functional moiety can provide a metal surface amenable to downstream coating processes, leading to efficient coating processes, uniform coating coverage, and reduced coating waste.

[0057] In some examples, the graft copolymer pretreatment compositions described herein include a corrosion inhibitor functional moiety. In some cases, the corrosion inhibitor functional moiety is a galvanic corrosion inhibitor (e.g., an inorganic chemical corrosion inhibitor, an organic corrosion inhibitor, or any combination thereof), or a barrier-type corrosion inhibitor (e.g., an inorganic barrier-type corrosion inhibitor, an organic barrier-type corrosion inhibitor, or any combination thereof). In certain aspects, the graft copolymer pretreatment compositions described herein can include one or more inorganic chemical corrosion inhibitors. The inorganic chemical corrosion inhibitors for use in the pretreatment compositions include any inorganic chemical species capable of chemically inhibiting or preventing corrosion of an aluminum alloy, such as by reacting to form a different chemical (e.g., an oxide) on the surface of the alloy and / or providing additional protection to the surface metal by being embedded in the coating. In certain cases, the graft copolymer pretreatment compositions can optionally include organic corrosion inhibitors. Non-limiting examples of suitable organic corrosion inhibitors include mercaptobenzothiazole (MBT), benzotriazole (BTA), salicylaldoxime, dithiooxamide, quinaldic acid, thioacetamide, 8-hydroxyquinoline (HXQ), and mixtures thereof.

[0058] In some examples, the inorganic chemical corrosion inhibitors as described herein optionally include one or more transition metals or salts thereof, and / or one or more rare earth metals or salts thereof. However, in embodiments, the pre-treatment composition may be generally free of metal ions, in embodiments. Suitable transition metals for use as inorganic chemical corrosion inhibitors can include, for example, titanium (Ti), vanadium (V), chromium (Cr), manganese (Mn), iron (Fe), cobalt (Co), nickel (Ni), copper (Cu), zinc (Zn), zirconium (Zr), niobium (Nb), molybdenum (Mo), ruthenium (Ru), rhodium (Rh), palladium (Pd), silver (Ag), cadmium (Cd), hafnium (Hf), tantalum (Ta), tungsten (W), rhenium (Re), osmium (Os), iridium (Ir), platinum (Pt), or gold (Au). Suitable rare earth metals for use as inorganic chemical corrosion inhibitors can include, for example, cerium (Ce), scandium (Sc), yttrium (Y), lanthanum (La), praseodymium (Pr), neodymium (Nd), promethium (Pm), samarium (Sm), europium (Eu), gadolinium (Gd), terbium (Tb), dysprosium (Dy), holmium (Ho), erbium (Er), thulium (Tm), ytterbium (Yb), and lutetium (Lu).Attorney Docket No. 108050-1530445

[0059] Optionally, the inorganic chemical corrosion inhibitor is a transition metal salt or a rare earth metal salt. Optionally, the transition metal salt or the rare earth metal salt includes a transition metal salt or a rare earth metal in an oxidation state of + 1, +2, +3, +4, +5, or +6. For example, the transition metal salt or the rare earth metal salt can be a salt that includes molybdenum II ions, molybdenum III ions, molybdenum IV ions, molybdenum V ions, molybdenum VI ions, zirconium II ions, zirconium III ions, zirconium IV ions, titanium II ions, titanium III ions, titanium IV ions, cerium II ions, cerium III ions, or cerium IV ions. In certain examples, the metallic ions described above can be incorporated between at least two layers of the graft copolymer pretreatment compositions described herein for enhanced corrosion resistance. For example, a metal product can be coated with the graft copolymer pretreatment composition to form a layer. Metallic ions can be deposited onto the graft copolymer pretreatment composition layer. Optionally, an additional layer of the graft copolymer pretreatment composition can be applied to the resulting product.

[0060] In some cases, the rare earth metal salt can be an anhydrous salt. In some cases, the rare earth metal salt can be a hydrated salt, for example, a monohydrate salt, a dihydrate salt, a trihydrate salt, a tetrahydrate salt, a pentahydrate salt, a hexahydrate salt, a heptahydrate salt, an octahydrate salt, a nonahydrate salt, and / or a decahydrate salt. In some examples, the rare earth metal salt is a rare earth metal nitrate. Examples of suitable inorganic chemical corrosion inhibitors include cerium (III) nitrate hexahydrate (Ce(NO3)3*6H2O), yttrium nitrate hexahydrate (Y(NO3)3*6H2O), ytterbium nitrate hexahydrate (Yb(NO3)3*6H2O), and lanthanum nitrate hexahydrate (La(NO3)3*6H2O).

[0061] In some examples, the graft copolymer pretreatment compositions described herein include a weld promoter functional moiety. Incorporating a weld promoter functional moiety can disrupt the surface tension between metal products that are contacted for a welding process (e.g., resistance spot welding, resistance seam welding, friction stir welding, gas metal arc welding (e.g., metal inert gas welding or tungsten inert gas welding), plasma arc welding, laser welding, refill friction stir spot welding, any suitable welding process, or any combination thereof). In some embodiments, the weld promoter functional moiety can comprise titanium (Ti), zirconium (Zr), or a combination thereof.

[0062] However, as discussed above, at least one of the surface binding or bonding moiety and the at least one functional moiety include one or more functional groups suitable for crosslinking with a further surface binding or bonding moiety and / or functional moiety. For instance, in embodiments, at least one at least one of the surface binding or bondingAttorney Docket No. 108050-1530445moiety and the at least one functional moiety may include a functional group that may form an anhydride or ester linkage. In embodiments, the at least one of the surface binding or bonding moiety and the at least one functional moiety include a phosphonate group, a phosphate group, a phosphoryl group, a carboxyl group, a catechol group, or a trialkoxysilyl group, as well as one or more functional groups that form one or more bonds with an further surface binding or bonding moiety and / or functional moiety, such as during a condensation reaction. For instance, in embodiments, the at least one of the surface binding or bonding moiety and the at least one functional moiety include a hydroxyl group, forming an anhydride bond with a hydroxyl group of a further surface binding or bonding moiety and / or functional moiety. In embodiments, the at least one functional moiety may contain the one or more functional groups suitable for crosslinking with a further surface binding or bonding moiety and / or functional moiety.Exemplary Graft Copolymer Pretreatment Compositions

[0063] In some examples, the graft copolymer pretreatment compositions described herein, along with a binding or bonding moiety, can provide a multi-functional surface coating to the metal surface. In some cases, the graft copolymer pretreatment compositions can include any combination of a binding or bonding moiety, a corrosion inhibitor functional moiety, an adhesion promoter functional moiety, a lubricant functional moiety, a humectant functional moiety, and / or a weld promoter functional moiety. For example, the graft copolymer pretreatment can include a binding or bonding moiety and a lubricant functional moiety. In some cases, the graft copolymer pretreatment can include a binding or bonding moiety and a corrosion inhibiting moiety. In some cases, the graft copolymer pretreatment can include a binding or bonding moiety and an adhesion promoting moiety. In some other cases, the graft copolymer pretreatment can include a binding or bonding moiety, a lubricant functional moiety, and an adhesion promoting moiety. In certain examples, the graft copolymer pretreatment can include a binding or bonding moiety, a lubricant functional moiety, and a humectant moiety. Further, the graft copolymer pretreatment can include a binding or bonding moiety and a humectant moiety. Still further, the graft copolymer pretreatment can include a binding or bonding moiety and a weld promoting moiety. In some non-limiting examples, the graft copolymer pretreatment can include a binding or bonding moiety, a corrosion inhibiting moiety, and an adhesion promoting moiety. In certain aspects, the graft copolymer pretreatment can include a binding or bonding moiety, a corrosionAttorney Docket No. 108050-1530445inhibiting moiety, an adhesion promoting moiety, and a lubricant functional moiety. In some examples, the graft copolymer pretreatment can include a binding or bonding moiety, a corrosion inhibiting moiety, an adhesion promoting moiety, and a weld promoting moiety. In some aspects, the graft copolymer pretreatment can include a binding or bonding moiety, a corrosion inhibiting moiety, and a lubricant functional moiety. These are a few non-limiting examples, as the graft copolymer pretreatment can include a binding or bonding moiety and any combination of any suitable functional moieties.

[0064] An exemplary graft copolymer pretreatment composition as described herein, including the surface binding moiety and functional moieties, is depicted in Formula IV below:In Formula IV, X1, X2, X3, and X4are each independently selected from hydrogen and methyl. Also in Formula IV, each of m, n, o, and p is independently and optionally present in a range of from 1 to 1000 (e.g., from 1 to 100, from 1 to 50, or from 1 to 30). In some examples, one or more of m, n, o, and p is present (e.g., two of m, n, o, and p are present; three of m, n, o, and p are present; or each of m, n, o, and p are present). Further in Formula IV, R1, R2, R3, and R4are each independently selected, if present, from -O- or -NR6-, wherein R6is substituted or unsubstituted alkyl, substituted or unsubstituted alkenyl, substituted or unsubstituted alkynyl, substituted or unsubstituted aryl, substituted or unsubstituted heteroaryl, substituted or unsubstituted cycloalkyl, or substituted or unsubstituted heterocycloalkyl. Additionally in Formula IV, R5is a spacer group, for example, (CFb)^, wherein q is in the range of 1 to 30 (e.g., q = 1-30, q = 1-25, q = 1-20, q = 1-15, q = 1-10, q = 1-5, q=l-3, q=l-2, q = 5-30 q = 5-25, q = 5-20, q = 5-15, q = 5-10 q = 10-30, q = 10-25, q = 10-20, q = 10-15, q = 15-30, q = 15-25, q = 15-20, q = 20-30, q = 20-25, or q = 25-30, or ranges or values therebetween).

[0065] Further in Formula IV, A is a surface binding or bonding moiety as described herein. Optionally, A is selected from the group consisting of phosphonic acid (PO3H2), phosphoric acid (PO4H2), a carboxylic acid (COOH), a trialkoxysilyl group (-Si(OR)3,Attorney Docket No. 108050-1530445wherein R is an alkyl, alkenyl, alkynyl, heteroalkyl, heteroalkenyl, heteroalkynyl cycloalkyl, cycloalkenyl, cycloalkynyl, heterocycloalkyl, heterocycloalkenyl, or heterocycloalkynyl group), and / or various catechol derivatives as shown in Formula V and Formula VI below:In Formula V and Formula VI, R7is selected from a hydrogen, a hydroxyl group, an electronwithdrawing group (e.g., a nitro group, a carboxy group, or a halide (e.g., fluoride, chloride, bromide, or iodide)).

[0066] In some examples, Pol in Formula IV is a functional moiety that is optionally present. In some examples, Pol is a polymeric chain that can function as a lubricant, such as a poly(ethylene glycol) chain, a poly(tetrahydrofuran) chain, a poly (isoprene) chain, a hydrogenated poly (isoprene) chain, a poly(butadiene) chain, a hydrogenated poly(butadiene) chain, or a polyisobutene chain.

[0067] In some cases, FG in Formula IV is a functional moiety that is optionally present, wherein the functional moiety can be an adhesive compound or any other functional moiety as described herein. Optionally, FG can be a hydroxyl, an amide, a thiol, an epoxide, a vinyl, a diol, a phosphonic acid, a phosphoric acid, a carboxylic acid, a sulfonic acid, a multivalent cation including any transition metal ion, or any rare earth metal ion. In some non-limiting examples, when FG is a phosphonic acid, a phosphoric acid, any one of a molybdenum ion, zirconium ion, or titanium ion can be incorporated into the graft copolymer pretreatment composition. In some cases, FG can be a halide, an ethylene oxide, a trialkoxy silyl, a hydroxyethyl group, a 2-methacryloyloxyethyl group, a 2,2,2-trifluoroethyl group, or a butyl group.Attorney Docket No. 108050-1530445Polymer Synthesis

[0068] The polymers for the pretreatment compositions described herein can be prepared by synthesizing a polymer having surface binding or bonding moieties and functional moieties by polymerizing or copolymerizing suitable monomers by a chain polymerization method, such as radical polymerization, cationic polymerization, anionic polymerization, catalytic polymerization, or group transfer polymerization. In some cases, the polymer backbone is a homopolymer backbone provided by polymerizing a single type of repeat unit (e.g., a monomer). Optionally, the polymer backbone can be a copolymer backbone provided by polymerizing a variety of different monomers by a chain polymerization method, such as radical polymerization, cationic polymerization, anionic polymerization, catalytic polymerization, or group transfer polymerization. Each repeat unit can include a surface binding or bonding moiety, a functional moiety, both a surface binding or bonding moiety and a functional moiety, or the repeat unit can be devoid of a pendant functional moiety (e.g., a backbone spacer).

[0069] In some non-limiting cases, the polymers for the pretreatment compositions described herein can be prepared by synthesizing a polymer backbone having surface binding moieties and optional functional moieties by a radical polymerization or copolymerization of methacrylic or acrylic monomers, such as methyl methacrylate, methacryloyloxy(methyl)phosphonic acid (MMPA), hydroxyxy ethyl methacrylate (HEMA), 2-methacryloyloxyethyl phosphate (HEMA-P), or poly(ethylene glycol) methyl ether methacrylate (PEGMEMA). Number average molecular weights (Mi) of the poly(ethylene glycol) chain can range, for example, from 300 to 5000 g / mol (e.g., 300, 400, 700, 1000, 2000, or 5000 g / mol).

[0070] In certain aspects, a polymerization can be performed using a monomer (e.g., poly(ethylene glycol) methyl ether methacrylate, having aM = 300-2000 (PEGMEMA-300-2000)), an initiator (e.g., 4,4'-Azobis(4-cyanopentanoic acid (ACPA)), and abase (e.g., A,A,A’,A’-tetramethylenediamine (TEMED)) in a predetermined stoichiometric ratio in a solvent (e.g., water, methanol, ethanol, isopropanol, n-butanol, dimethylformamide, dimethyl sulfoxide, acetonitrile, acetone, tetrahydrofuran, methyl ethyl ketone, or any combination thereof). Additionally, a copolymer polymerization can be performed using at least two monomers (e.g., PEGMEMA-300-2000 and (methacryloyloxy)methylphosphonic acid (MMPA)), an initiator (e.g., ACPA), and a base (e.g., TEMED) in a predetermined stoichiometric ratio in a solvent as described above.Attorney Docket No. 108050-1530445

[0071] In some aspects, the copolymer polymerization may be performed using PEGMEMA and HEMA-P to form a copolymer as illustrated below:, portion of the copolymer may contribute tolubrication and theportion of the copolymer may contribute to surface anchor crosslinking. Each of x and y is independently and optionally present in a range of from 1 to 1000 (e.g., from 1 to 100, from 1 to 50, or from 1 to 30).

[0072] Exemplary synthetic methods for preparing polymers for the pretreatment compositions described herein are detailed below in Example 1.Graft Copolymer Pretreatment Composition-Treated Aluminum Alloys

[0073] Disclosed herein are metal and alloy substrates, such as aluminum alloys, containing at least one surface that is treated with a graft copolymer pretreatment composition as described herein. The coatings described herein are suitable for providing corrosion protection, improved adhesion, lubrication, improved wetting, and / or improved weld performance to any metal or alloy (e.g., an aluminum alloy). The graft copolymerAttorney Docket No. 108050-1530445pretreatment compositions disclosed herein may also be referred to as coatings, films, or layers. While aluminum alloys are described and exemplified, the compositions and methods described herein may also be used to treat other metals and alloys, including mild steel, galvanized steel, and magnesium alloys, to name a few, as set forth above.

[0074] The disclosed coated metals and / or alloys have a surface coating layer that includes a polymer backbone (e.g., a chain polymer polymerized from acrylic monomers or methacrylic monomers), at least one surface bonding or binding moiety attached to the polymer backbone and configured to bond the graft copolymer pretreatment compositions to the metal and / or alloy surface, and at least one functional moiety attached to the polymer backbone configured to impart a surface functionalization to the metal and / or alloy surface. As described above, the surface functionalization includes resistance to corrosion, improved adhesion, lubrication, improved wetting, and / or improved weld performance. As discussed above, in embodiments, the bonding or binding moiety may include a phosphonate or phosphorate containing moiety, as well as others as discussed above.

[0075] Optionally, the method includes a step of degreasing the aluminum alloy surface and / or a step of etching the aluminum alloy surface prior to the coating application. The method can further include cleaning the aluminum alloy, rinsing the aluminum alloy, and drying the aluminum alloy prior to applying the pretreatment solution.

[0076] Nonetheless, the method may be discussed in conjunction with FIGS. 1 A-1C. For instance, FIG. 1 A provides a metal and / or alloy substrate 300 having at least one surface 302. In some examples, at least one surface 302 of a metal and / or alloy 300 (e.g., an aluminum alloy substrate, such as an aluminum alloy coil) can be coated by applying a graft copolymer pretreatment composition as described herein to the alloy to form an initial coating layer 305a, as illustrated in FIG. 3. The pretreatment composition can be applied to at least one surface 302 of an aluminum alloy 300 by any suitable method. In some cases, the graft copolymer pretreatment compositions are coated from a solution containing the graft copolymer pretreatment compositions (e.g., an aqueous graft copolymer pretreatment solution, an organic solvent graft copolymer pretreatment solution, or a combination thereof). For example, the coatings described herein can be applied by roll coating, spray coating, dip coating, electrodeposition, glaze coating, or drop coating a suitable graft copolymer pretreatment solution. These methods are generally known in the art.

[0077] Nonetheless, after applying the graft copolymer pretreatment solution, the graft copolymer pretreatment solution can be cured at carefully tailored temperatures and times, toAttorney Docket No. 108050-1530445form an aluminum alloy that includes a coating layer of the crosslinked graft copolymer pretreatment composition 305b, as illustrated in FIG. 1C. After drying, the graft copolymer pretreatment composition becomes a coating layer having the crosslinked graft copolymer pretreatment composition as desired (e.g., including any one of, any combination of, or all of a corrosion inhibitor, an adhesion promoter, a surfactant, an antioxidant, a lubricant, a humectant, a weld promoter, a hydrophobic functionality (e.g., a self-cleaning surface and / or a water-repellant surface), an oleophobic functionality (e.g., an anti-fouling surface), a hydrophilic functionality (e.g., a biocompatible surface), an optical functionality (e.g., a dye, a pigment, an optical waveguide, a photoluminescent surface, or a negative refractive index surface), or any combination thereof).

[0078] For instance, in embodiments, the pretreatment composition may include one or more adhesion promoters. In embodiments, an adhesion promoter may improve bonding to the pretreated metal substrate. Adhesion promoters may include one or more phosphorous containing organic acids, such as a phosphonic and / or phosphoric acid, or one or more biscarboxylic acids, one or more silanes, or combinations thereof. In embodiments, the phosphonic or phosphoric acids may be bifunctional phosphonic or phosphoric acids.Example phosphorus-containing organic acids include, but are not limited to, those having a formula of R-OPO(OH)2, R-PO(OH)2 or R-PO(OH)R, where each R is independently hydrogen, a functionalized or unfunctionalized alkyl group, a functionalized or unfunctionalized alkenyl group, a functionalized or unfunctionalized alkynyl group, a phosphoric acid group,, or any combination of these. Optionally, a phosphorus-containing organic acid may have a formula of: X-(CR1R2)n-PO(OH)2 or X-(CR1R2)n-PO(OH)H, where n is an integer from 3 to 30, where each R1and R2is independently a hydrogen or a substituted or unsubstituted alkyl, alkenyl, or alkynyl group, and where X is an -OH group, an -NH group, an -SH group, a -PO(OH)2 group, a -PO(OH)H group, an -SO3H group, a -COOH group, a trialkoxysilyl group, a vinyl group, an ethynyl group, an epoxy group, an acrylate group, a methacrylate group, or a methyl group. In embodiments, the organic acid may include a polyethylene glycol, such as where one of R1and R2are polyetheylene glycol. For instance, an exemplary bifunctional phosphonic acids may include [Oxybis(2,l-ethanediyloxy-2,l-ethanediyl)]bis-phosphonic acid. Optionally, any R, R1, or R2may be functionalized with one or more -OH groups, -NH2 groups, -SH groups, -PO(OH)2 groups, -PO(OH)H groups, -SO3H groups, -COOH groups, trialkoxysilyl groups, vinyl groups, ethynyl groups, epoxy groups, acrylate groups, methacrylate groups, or anyAttorney Docket No. 108050-1530445combination of these. In some examples, the phosphorus-containing organic acid has a formula of X-(CH2)n-PO(OH)2 or X-(CH2)n-P0(0H)H. Nonetheless, in embodiments, the adhesion promoter may include (6-Phosphonohexyl)) phosphonic acid, 11-Hydroxyundecyl-phosphonic acid, or combinations thereof. Furthermore, in embodiments, one or more biscarboxylic acids may be utilized, and / or one or more silanes, such as bis-triethoxysilane, in embodiments. In embodiments, the silane may have the general structure, R3Si-(CH2)x-SiR3.

[0079] In embodiments, the one or more adhesion promoters may be present in the pretreatment composition in an amount of about 0.1 wt.% to about 6.0 wt.%, or from 0.5 wt.% to 5.5 wt.%, or from 1.0 to 5.0 wt.%, or from 1.5 wt.% to 4.5 wt.%, or from 2.0 wt.% to 4.0 wt.%, or from 2.5 wt.% to 3.5 wt.%, based upon the weight of the graft copolymer in the pretreatment solution, or any ranges or values therebetween, such as containing less than 6 wt.% adhesion promoter, less than 5.8 wt.%, less than 5.6 wt.%, less than 5.4 wt.%, less than 5.2 wt.%, less than 5 wt.%, less than 4.8 wt.%, less than 4.6 wt.%, less than 4.4 wt.%, less than 4.2 wt.%, less than 4 wt.%, less than 3.8 wt.%, less than 3.6 wt.%, less than 3.4 wt.%, less than 3.2 wt.%, less than 3 wt.%, less than 2.8 wt.%, less than 2.6 wt.%, less than 2.4 wt.%, less than 2.2 wt.%, less than 2 wt.%, less than 11.8 wt.%, less than 1.6 wt.%, less than 1.4 wt.%, less than 1.2 wt.%, less than 1 wt.%, less than 0.8 wt.%, less than 0.6 wt.%, less than 0.4 wt.%, less than 0.2 wt.%, less than 0.1 wt.%, less than 0.01 wt.%, less than 0.001 wt.%, or greater than 0.001 wt.%, greater than 0.01 wt.%, greater than 0.1 wt.%, greater than 0.5 wt.%, greater than 1.0 wt.%, greater than 1.5 wt.%, greater than 2.0 wt.%, greater than 2.5 wt.%, or any ranges or values therebetween.

[0080] In embodiments, the pretreatment composition may also include one or more antioxidants. For instance, as discussed above, in embodiments, it may be desired to heat the pretreatment solution in order to crosslink the pretreatment solution, or further process the metal product. However, graft copolymer pretreatment compositions may be susceptible to oxidation at high temperatures. Therefore, it may be desirable to include one or more antioxidants. An antioxidant may include a hindered tertiary-butyl-phenol antioxidant, butylated hydroxytoluene (BHT), butylated hydroxyanisole (BHA), propyl gallate, vitamin E, or combinations thereof. In embodiments, the antioxidant may include propyl gallate (CAS 121-79-9), 2-tert-butyl-4-methoxyphenol (CAS 121-00-6), tert-butyl-hydroquinone (CAS 1948-33-0), or combinations thereof.

[0081] In embodiments, the one or more antioxidants may be present in the pretreatment composition in an amount of about 0.1 wt.% to about 3.0 wt.%, or from 0.3 wt.% to 2.5 wt.%,Attorney Docket No. 108050-1530445or from 0.5 to 2.0 wt.%, or from 0.7 wt.% to 1.5 wt.%, or from 0.9 wt.% to 1.2 wt.%, based upon the weight of the graft copolymer in the pretreatment solution, or any ranges or values therebetween, such as containing less than 3 wt.% antioxidants, less than 2.8 wt.%, less than 2.6 wt.%, less than 2.4 wt.%, less than 2.2 wt.%, less than 2 wt.%, less than 1.8 wt.%, less than 1.6 wt.%, less than 1.4 wt.%, less than 1.2 wt.%, less than 1 wt.%, less than 0.8 wt.%, less than 0.6 wt.%, less than 0.4 wt.%, less than 0.2 wt.%, less than 0.1 wt.%, less than 0.01 wt.%, less than 0.001 wt.%, or greater than 0.001 wt.%, greater than 0.01 wt.%, greater than 0.1 wt.%, greater than 0.5 wt.%, greater than 1.0 wt.%, greater than 1.5 wt.%, greater than 2.0 wt.%, greater than 2.5 wt.%, or any ranges or values therebetween.

[0082] In embodiment, the pretreatment composition includes one or more surfactants. In embodiments, surfactants may allow improved wetting of the metal surface with the pretreatment composition, such as by altering a surface energy of the coating composition. Advantageously, even low amounts of surfactant allowed for a large reduction in the solvent needed for adequate wetting. Thus, even low amounts of surfactant may allow for a largely water borne pretreatment composition (e.g. greater than 99% water). In embodiments, surfactants may include silicon surfactants. In embodiments, surfactants may include Pluronic P123 (supplied by Merck) and / or BYK (supplied by BYK Chemie GMBh), such as BYK348.

[0083] In embodiments, the one or more surfactants may be present in the pretreatment composition in an amount of about 0.001 wt.% to about 1.0 wt.%, or from 0.005 wt.% to 0.8 wt.%, or from 0.01 to 0.8 wt.%, or from 0.015 wt.% to 0.6 wt.%, or from 0.02 wt.% to 0.4 wt.%, from 0.02 to 0.1, wt.%, based upon the weight of the graft copolymer in the pretreatment solution, or any ranges or values therebetween, such as containing less than 1 wt.% surfactant, less than 0.8 wt.%, less than 0.6 wt.%, less than 0.4 wt.%, less than 0.2 wt.%, less than 0.1 wt.%, less than 0.05 wt.%, less than 0.03 wt.%, less than 0.01 wt.%, less than 0.001 wt.%, or greater than 0.001 wt.%, greater than 0.01 wt.%, greater than 0.02 wt.%, or any ranges or values therebetween

[0084] For instance, FIG. 2 illustrates a schematic representation of the crosslinked graft copolymer pretreatment solution. The illustration shows anhydride bonds formed between respective phosphoric or phosphonic acid groups on one or more surface bonding or binding agents, as discussed above. However, it should be clear that FIG. 2 is for exemplary purposes only, and that the present technology contemplates other functional groups with crosslinking as discussed herein. For instance, one or two anhydrides may be formed per acid group, and cyclic structures, including six-membered rings, are contemplated herein.Attorney Docket No. 108050-1530445

[0085] The crosslinked graft copolymer pretreatment layer is illustrated as having a thickness of approximately 150 to 300 nm, but it should be clear that other layer thicknesses are contemplated herein, based upon the desired use of the substrate. For instance, in embodiments, the crosslinked graft copolymer pretreatment layer may be applied at a thickness of from 20 nm to 700 nm, 25 nm to 675 nm, 30 nm to 650 nm, or such as greater than 20 nm, greater than 25 nm greater than 30 nm, greater than 35 nm, greater than 40 nm, greater than 45 nm, greater than 50 nm, greater than 55 nm, greater than 60 nm, greater than 65 nm, greater than 70 nm, greater than 75 nm, greater than 80 nm, greater than 85 nm, greater than 90 nm, greater than 95 nm, greater than 100 nm, greater than 105 nm, greater than 110 nm, greater than 115 nm, greater than 120 nm, greater than 130 nm, greater than 135 nm, greater than 140 nm, greater than 145 nm, greater than 150 nm, greater than 155 nm, greater than 160 nm, greater than 165 nm, greater than 170 nm, greater than 175 nm, greater than 180 nm, greater than 185 nm, greater than 190 nm, greater than 195 nm, greater than 200 nm, greater than 205 nm, greater than 210 nm, greater than 215 nm, greater than 220 nm, greater than 230 nm, greater than 235 nm, greater than 240 nm, greater than 245 nm, greater than 250 nm, greater than 255 nm, greater than 260 nm, greater than 265 nm, greater than 270 nm, greater than 275 nm, greater than 280 nm, greater than 285 nm, greater than 290 nm, greater than 295 nm, greater than 300 nm, or such as less than 700 nm, less than 695 nm, less than 690 nm, less than 685 nm, less than 680 nm, less than 675 nm, less than 670 nm, less than 665 nm, less than 660 nm, less than 655 nm, less than 650 nm, less than 645 nm, less than 640 nm, less than 635 nm, less than 630 nm, less than 625 nm, less than 620 nm, less than 615 nm, less than 610 nm, less than 605 nm, less than 600 nm, less than 595 nm, less than 590 nm, less than 585 nm, less than 580 nm, less than 575 nm, less than 570 nm, less than 565 nm, less than 560 nm, less than 555 nm, less than 550 nm, less than 545 nm, less than 540 nm, less than 535 nm, less than 530 nm, less than 525 nm, less than 520 nm, less than 515 nm, less than 510 nm, less than 505 nm, less than 500 nm, less than 495 nm, less than 490 nm, less than 485 nm, less than 480 nm, less than 475 nm, less than 470 nm, less than 465 nm, less than 460 nm, less than 455 nm, less than 450 nm, less than 445 nm, less than 440 nm, less than 435 nm, less than 430 nm, less than 425 nm, less than 420 nm, less than 415 nm, less than 410 nm, less than 405 nm, less than 400 nm, less than 395 nm, less than 390 nm, less than 385 nm, less than 380 nm, less than 375 nm, less than 370 nm, less than 365 nm, less than 360 nm, less than 355 nm, less than 350 nm, less than 345 nm, less than 340 nm, less than 335 nm, less than 330 nm, less than 325 nm, less than 320 nm, lessAttorney Docket No. 108050-1530445than 315 nm, less than 310 nm, less than 305 nm, less than 300 nm, or any ranges or values therebetween. The thickness may be measured as a dried film, or as an applied thickness during coating of the pretreatment composition.

[0086] Surprisingly, by utilizing the heating and / or drying discussed herein, a significant amount of the applied crosslinked graft copolymer pretreatment layer may be maintained, even after rinsing. Thus, in embodiments a residual crosslinked graft copolymer pretreatment layer thickness, which may be measured after rinsing with a solvent, such as water, may be greater than 30% of the applied crosslinked graft copolymer pretreatment layer thickness, greater than 35%, greater than 40%, greater than 45%, greater than 50%, greater than 55%, greater than 60%, greater than 65%, greater than 70%, greater than 75%, greater than 80%, greater than 85%, greater than 90%, or any ranges or values therebetween.

[0087] Stated differently, a residual crosslinked graft copolymer pretreatment layer may have a thickness from 20 nm to 550 nm, 25 nm to 525 nm, 30 nm to 500 nm, or such as greater than 20 nm, greater than 25 nm greater than 30 nm, greater than 35 nm, greater than 40 nm, greater than 45 nm, greater than 50 nm, greater than 55 nm, greater than 60 nm, greater than 65 nm, greater than 70 nm, greater than 75 nm, greater than 80 nm, greater than 85 nm, greater than 90 nm, greater than 95 nm, greater than 100 nm, greater than 105 nm, greater than 110 nm, greater than 115 nm, greater than 120 nm, greater than 130 nm, greater than 135 nm, greater than 140 nm, greater than 145 nm, greater than 150 nm, greater than 155 nm, greater than 160 nm, greater than 165 nm, greater than 170 nm, greater than 175 nm, greater than 180 nm, greater than 185 nm, greater than 190 nm, greater than 195 nm, greater than 200 nm, greater than 205 nm, greater than 210 nm, greater than 215 nm, greater than 220 nm, greater than 230 nm, greater than 235 nm, greater than 240 nm, greater than 245 nm, greater than 250 nm, greater than 255 nm, greater than 260 nm, greater than 265 nm, greater than 270 nm, greater than 275 nm, greater than 280 nm, greater than 285 nm, greater than 290 nm, greater than 295 nm, greater than 300 nm, or such as less than 550 nm, less than 545 nm, less than 540 nm, less than 535 nm, less than 530 nm, less than 525 nm, less than 520 nm, less than 515 nm, less than 510 nm, less than 505 nm, less than 500 nm, less than 495 nm, less than 490 nm, less than 485 nm, less than 480 nm, less than 475 nm, less than 470 nm, less than 465 nm, less than 460 nm, less than 455 nm, less than 450 nm, less than 445 nm, less than 440 nm, less than 435 nm, less than 430 nm, less than 425 nm, less than 420 nm, less than 415 nm, less than 410 nm, less than 405 nm, less than 400 nm, less than 395 nm, less than 390 nm, less than 385 nm, less than 380 nm, less than 375 nm, less than 370 nm,Attorney Docket No. 108050-1530445less than 365 nm, less than 360 nm, less than 355 nm, less than 350 nm, less than 345 nm, less than 340 nm, less than 335 nm, less than 330 nm, less than 325 nm, less than 320 nm, less than 315 nm, less than 310 nm, less than 305 nm, less than 300 nm, less than 295 nm, less than 290 nm, less than 285 nm, less than 280 nm, less than 275 nm, less than 270 nm, less than 265 nm, less than 260 nm, less than 255 nm, less than 250 nm, or any ranges or values therebetween. The thickness may be measured as a dried film, or as an applied thickness during coating of the pretreatment composition.

[0088] Namely, the present technology has surprisingly found that by carefully controlling the curing temperature and time, or by heating the crosslinked graft copolymer pretreatment layer for the temperature and time prior to cooling and drying at a lower temperature, enhanced crosslinking is exhibited such that the crosslinked graft copolymer pretreatment layer exhibits excellent stability even without an external crosslinking agent. Thus, in embodiments, the crosslinkage discussed herein may be considered to be generally free of external crosslinking agents, such as containing less than 5 wt.% external crosslinking agents, less than 4.8 wt.%, less than 4.6 wt.%, less than 4.4 wt.%, less than 4.2 wt.%, less than 4 wt.%, less than 3.8 wt.%, less than 3.6 wt.%, less than 3.4 wt.%, less than 3.2 wt.%, less than 3 wt.%, less than 2.8 wt.%, less than 2.6 wt.%, less than 2.4 wt.%, less than 2.2 wt.%, less than 2 wt.%, less than 11.8 wt.%, less than 1.6 wt.%, less than 1.4 wt.%, less than 1.2 wt.%, less than 1 wt.%, less than 0.8 wt.%, less than 0.6 wt.%, less than 0.4 wt.%, less than 0.2 wt.%, less than 0.1 wt.%, less than 0.01 wt.%, less than 0.001 wt.%, or any ranges or values therebetween, based upon the weight of the crosslinked graft copolymer pretreatment layer before or after drying. Furthermore, as discussed above, it should be understood that, in embodiments, “external crosslinking agent” may include a crosslinking agent added to the graft copolymer pretreatment layer, and may therefore refer to any compound or precursor that exhibits crosslinking other than between one or more of the surface bonding or binding moiety and the one or more functional moiety, and a further surface bonding or binding moiety and functional moiety, as discussed above.

[0089] Thus, in embodiments, the curing of the graft copolymer pretreatment layer, forming the crosslinked graft copolymer pretreatment layer, may be conducted at a temperature of 60 °C to 250 °C, from 70 °C to 245 °C, or from 80 °C to 240 °C, such as greater than 60 °C, greater than 65 °C, greater than 70 °C, greater than 75 °C, greater than 80 °C, greater than 85 °C, greater than 90 °C, greater than 95 °C, greater than 100 °C, greater than 105 °C, greater than 110 °C, greater than 115 °C, greater than 120 °C, greater than 125 °C,Attorney Docket No. 108050-1530445greater than 130 °C, greater than 135 °C, greater than 140 °C, greater than 145 °C, greater than 150 °C, greater than 155 °C, greater than 160 °C, greater than 165 °C, greater than 170 °C, greater than 175 °C, greater than 180 °C, greater than 185 °C, greater than 190 °C, greater than 195 °C, greater than 200 °C, greater than 205 °C, greater than 210 °C, greater than 215 °C, greater than 220 °C, greater than 225 °C, greater than 230 °C, greater than 235 °C, greater than 240 °C, greater than 245 °C, or such as less than 250 °C, less than 245 °C, less than 240 °C, less than 235 °C, less than 230 °C, less than 225 °C, less than 220 °C, less than 215 °C, less than 210 °C, less than 205 °C, less than 200 °C, less than 195 °C, less than 190 °C, less than 185 °C, less than 180 °C, less than 175 °C, less than 170 °C, less than 165 °C, less than 160 °C, less than 155 °C, less than 150 °C, less than 145 °C, less than 140 °C, less than 135 °C, less than 130 °C, less than 125 °C, less than 120 °C, less than 115 °C, less than 110 °C, less than 105 °C, less than 100 °C, or any ranges or values therebetween. In such a manner, excellent crosslinking may be exhibited without denaturing the graft copolymer pretreatment composition.

[0090] In embodiments, to provide for adequate crosslinking without denaturing the graft copolymer pretreatment composition, the heating and / or drying may take place for 1 second to 15 minutes, from 5 seconds to 14 minutes, from 10 seconds to 12 minutes, or such as greater than 1 second, greater than 5 seconds, greater than 10 seconds, greater than 15 seconds, greater than 20 seconds, greater than 25 seconds greater than 30 seconds, greater than 35 seconds, greater than 40 seconds, greater than 45 seconds, greater than 50 seconds, greater than 55 seconds, greater than 60 seconds (one minute), greater than 65 seconds, greater than 70 seconds, greater than 75 seconds, greater than 80 seconds, greater than 85 seconds, greater than 90 seconds, greater than 95 seconds, greater than 100 seconds, greater than 105 seconds, greater than 110 seconds, greater than 115 seconds, greater than 120 seconds (two minutes), greater than 125 seconds greater than 130 seconds, greater than 135 seconds, greater than 140 seconds, greater than 145 seconds, greater than 150 seconds, greater than 155 seconds, greater than 160 seconds, greater than 165 seconds, greater than 170 seconds, greater than 175 seconds, greater than 180 seconds (three minutes), greater than 185 seconds, greater than 190 seconds, greater than 195 seconds, greater than 200 seconds, greater than 205 seconds, greater than 210 seconds, greater than 215 seconds, greater than 220 seconds, greater than 225 seconds, greater than 240 seconds (4 minutes), greater than 4.5 minutes, greater than 5 minutes, greater than 5.5 minutes, greater than 6 minutes, greater than 6.5 minutes, greater than 7 minutes, greater than 7.5 minutes, greater than 8 minutes, greaterAttorney Docket No. 108050-1530445than 8.5 minutes, greater than 9 minutes, greater than 9.5 minutes, greater than 10 minutes, or such as less than 15 minutes, less than 14.5 minutes, less than 14 minutes, less than 13.5 minutes, less than 13 minutes, less than 12.5 minutes, less than 12 minutes, less than 11.5 minutes, less than 11 minutes, less than 10.5 minutes, less than 10 minutes, less than 9.5 minutes, less than 9 minutes, less than 8.5 minutes, less than 8 minutes, less than 7.5 minutes, less than 7 minutes, less than 6.5 minutes, less than 6 minutes, less than 5.5 minutes, less than 5 minutes, less than 4.5 minutes, less than 4 minutes, less than 3.5 minutes, less than 3 minutes, less than 2.5 minutes less than 2 minutes, less than 1.5 minutes, less than 1 minute, or any ranges or values therebetween. However, in embodiments, curing may occur for less than or about 20 seconds, such as from 1 second to 20 seconds, 5 seconds to 15 seconds, or less than 20 seconds, less than 19 seconds, less than 18 seconds, less than 17 seconds, less than 16 seconds, less than 15 seconds, less than 14 seconds, less than 13 seconds, less than 12 seconds, less than 11 seconds, less than 10 seconds, or any ranges or values therebetween.

[0091] In embodiments, a lower heating and / or drying time may be utilized with higher drying and / or heating temperatures. For instance, as an example only, if the heating and / or drying time is 120 °C or less, it may be desirable to utilizing a heating and / or drying time of greater than 2 minutes, greater than 3 minutes, greater than 4 minutes, greater than 5 minutes, or more. If the drying temperature is greater than 120 °C, a shorter heating and / or drying time may be utilized, such as greater than 20 seconds, greater than 40 seconds, greater than 1 minute, or more. Thus, excellent crosslinking may be obtained while also preserving the nature of the pretreatment composition. If drying is conducted separately from the heating, drying may occur at a temperature of less than or about 60 °C, for a period of time sufficient to remove the solvent.

[0092] Surprisingly, the dried crosslinked graft copolymer pretreatment layer exhibits excellent sliding distance (in cm), as measured according to nanotribology, discussed in greater detail in the examples below. Sliding distance is the accumulated distance of a reciprocally moving pin with a defined normal load of 300 mN, until the pretreatment layer fails, resulting in a rapid increase in coefficient of friction. Thus, sliding distance may also be utilized to determine pretreatment layer thickness and robustness. The dried crosslinked graft copolymer pretreatment layer according to the present technology may exhibit a sliding distance of greater than 50 cm at 300 mN, greater than 55 cm, greater than 60 cm, greater than 65 cm, greater than 70 cm, greater than 75 cm, greater than 80 cm, greater than 85 cm, greater than 90 cm, greater than 95 cm, greater than 100 cm, greater than 105 cm, greaterAttorney Docket No. 108050-1530445than 110 cm, greater than 115 cm, greater than 120 cm, greater than 125 cm, greater than 130 cm, greater than 135 cm, greater than 140 cm, greater than 145 cm, greater than 150 cm, or such as less than 450 cm, less than 400 cm, less than 350 cm, less than 300 cm, ess than 250 cm, less than 200 cm, less than 175 cm, less than 150 cm, or any ranges or values therebetween.

[0093] Optionally, the coated aluminum alloys can be part of a joined structure including the coated aluminum alloy and a second metal or alloy of a different composition. For example, the coated aluminum alloy can be a Ixxx series alloy, a 2xxx series alloy, a 3xxx series alloy, a 4xxx series alloy, a 5xxx series alloy, a 6xxx series alloy, a 7xxx series alloy, or an 8xxx series alloy, prepared from a cast aluminum alloy product, that is joined to another alloy or metal.

[0094] Optionally, the aluminum alloy can be a Ixxx series aluminum alloy according to one of the following aluminum alloy designations: AA1100, AA1100A, AA1200, AA1200A, AA1300, AA1110, AA1120, AA1230, AA1230A, AA1235, AA1435, AA1145, AA1345, AA1445, AA1150, AA1350, AA1350A, AA1450, AA1370, AA1275, AA1185, AA1285, AA1385, AA1188, AA1190, AA1290, AA1193, AA1198, or AA1199.

[0095] Optionally, the aluminum alloy can be a 2xxx series aluminum alloy according to one of the following aluminum alloy designations: AA2001, A2002, AA2004, AA2005, AA2006, AA2007, AA2007A, AA2007B, AA2008, AA2009, AA2010, AA2011, AA2011A, AA2111, AA2111A, AA2111B, AA2012, AA2013, AA2014, AA2014A, AA2214, AA2015, AA2016, AA2017, AA2017A, AA2117, AA2018, AA2218, AA2618, AA2618A, AA2219, AA2319, AA2419, AA2519, AA2021, AA2022, AA2023, AA2024, AA2024A, AA2124, AA2224, AA2224A, AA2324, AA2424, AA2524, AA2624, AA2724, AA2824, AA2025, AA2026, AA2027, AA2028, AA2028A, AA2028B, AA2028C, AA2029, AA2030, AA2031, AA2032, AA2034, AA2036, AA2037, AA2038, AA2039, AA2139, AA2040, AA2041, AA2044, AA2045, AA2050, AA2055, AA2056, AA2060, AA2065, AA2070, AA2076, AA2090, AA2091, AA2094, AA2095, AA2195, AA2295, AA2196, AA2296, AA2097, AA2197, AA2297, AA2397, AA2098, AA2198, AA2099, or AA2199.

[0096] Optionally, the aluminum alloy can be a 3xxx series aluminum alloy according to one of the following aluminum alloy designations: AA3002, AA3102, AA3003, AA3103, AA3103A, AA3103B, AA3203, AA3403, AA3004, AA3004A, AA3104, AA3204, AA3304, AA3005, AA3005A, AA3105, AA3105A, AA3105B, AA3007, AA3107, AA3207, AA3207A, AA3307, AA3009, AA3010, AA3110, AA3011, AA3012, AA3012A, AA3013,Attorney Docket No. 108050-1530445AA3014, AA3015, AA3016, AA3017, AA3019, AA3020, AA3021, AA3025, AA3026, AA3030, AA3130, or AA3065.

[0097] Optionally, the aluminum alloy can be a 4xxx series aluminum alloy according to one of the following aluminum alloy designations: AA4004, AA4104, AA4006, AA4007, AA4008, AA4009, AA4010, AA4013, AA4014, AA4015, AA4015A, AA4115, AA4016, AA4017, AA4018, AA4019, AA4020, AA4021, AA4026, AA4032, AA4043, AA4043A, AA4143, AA4343, AA4643, AA4943, AA4044, AA4045, AA4145, AA4145A, AA4046, AA4047, AA4047A, or AA4147.

[0098] Optionally, the aluminum alloy can be a 5xxx series aluminum alloy according to one of the following aluminum alloy designations: AA5005, AA5005A, AA5205, AA5305, AA5505, AA5605, AA5006, AA5106, AA5010, AA5110, AA5110A, AA5210, AA5310, AA5016, AA5017, AA5018, AA5018A, AA5019, AA5019A, AA5119, AA5119A, AA5021, AA5022, AA5023, AA5024, AA5026, AA5027, AA5028, AA5040, AA5140, AA5041, AA5042, AA5043, AA5049, AA5149, AA5249, AA5349, AA5449, AA5449A, AA5050, AA5050A, AA5050C, AA5150, AA5051, AA5051A, AA5151, AA5251, AA5251A, AA5351, AA5451, AA5052, AA5252, AA5352, AA5154, AA5154A, AA5154B, AA5154C, AA5254, AA5354, AA5454, AA5554, AA5654, AA5654A, AA5754, AA5854, AA5954, AA5056, AA5356, AA5356A, AA5456, AA5456A, AA5456B, AA5556, AA5556A, AA5556B, AA5556C, AA5257, AA5457, AA5557, AA5657, AA5058, AA5059, AA5070, AA5180, AA5180A, AA5082, AA5182, AA5083, AA5183, AA5183A, AA5283, AA5283A, AA5283B, AA5383, AA5483, AA5086, AA5186, AA5087, AA5187, or AA5088.

[0099] Optionally, the aluminum alloy can be a 6xxx series aluminum alloy according to one of the following aluminum alloy designations: AA6101, AA6101A, AA6101B, AA6201, AA6201A, AA6401, AA6501, AA6002, AA6003, AA6103, AA6005, AA6005A, AA6005B, AA6005C, AA6105, AA6205, AA6305, AA6006, AA6106, AA6206, AA6306, AA6008, AA6009, AA6010, AA6110, AA6110A, AA6011, AA6111, AA6012, AA6012A, AA6013, AA6113, AA6014, AA6015, AA6016, AA6016A, AA6116, AA6018, AA6019, AA6020, AA6021, AA6022, AA6023, AA6024, AA6025, AA6026, AA6027, AA6028, AA6031, AA6032, AA6033, AA6040, AA6041, AA6042, AA6043, AA6151, AA6351, AA6351A, AA6451, AA6951, AA6053, AA6055, AA6056, AA6156, AA6060, AA6160, AA6260, AA6360, AA6460, AA6460B, AA6560, AA6660, AA6061, AA6061A, AA6261, AA6361, AA6162, AA6262, AA6262A, AA6063, AA6063A, AA6463, AA6463A, AA6763, A6963,Attorney Docket No. 108050-1530445AA6064, AA6064A, AA6065, AA6066, AA6068, AA6069, AA6070, AA6081, AA6181, AA6181A, AA6082, AA6082A, AA6182, AA6091, or AA6092.

[0100] Optionally, the aluminum alloy can be a 7xxx series aluminum alloy according to one of the following aluminum alloy designations: AA7011, AA7019, AA7020, AA7021, AA7039, AA7072, AA7075, AA7085, AA7108, AA7108A, AA7015, AA7017, AA7018, AA7019A, AA7024, AA7025, AA7028, AA7030, AA7031, AA7033, AA7035, AA7035A, AA7046, AA7046A, AA7003, AA7004, AA7005, AA7009, AA7010, AA7011, AA7012, AA7014, AA7016, AA7116, AA7122, AA7023, AA7026, AA7029, AA7129, AA7229, AA7032, AA7033, AA7034, AA7036, AA7136, AA7037, AA7040, AA7140, AA7041, AA7049, AA7049A, AA7149, AA7249, AA7349, AA7449, AA7050, AA7050A, AA7150, AA7250, AA7055, AA7155, AA7255, AA7056, AA7060, AA7064, AA7065, AA7068, AA7168, AA7175, AA7475, AA7076, AA7178, AA7278, AA7278A, AA7081, AA7181, AA7185, AA7090, AA7093, AA7095, or AA7099.

[0101] Optionally, the aluminum alloy can be an 8xxx series aluminum alloy according to one of the following aluminum alloy designations: AA8005, AA8006, AA8007, AA8008, AA8010, AA8011, AA8011A, AA8111, AA8211, AA8112, AA8014, AA8015, AA8016, AA8017, AA8018, AA8019, AA8021, AA8021A, AA8021B, AA8022, AA8023, AA8024, AA8025, AA8026, AA8030, AA8130, AA8040, AA8050, AA8150, AA8076, AA8076A, AA8176, AA8077, AA8177, AA8079, AA8090, AA8091, or AA8093.

[0102] Optionally, the coated aluminum alloys can be provided in any metallurgical state, for example, any suitable temper or condition. For example, the aluminum alloys can be provided in an F temper, an O temper, or a W temper as described above. In some cases, heat treatable aluminum alloys (e.g., 2xxx series aluminum alloys, 6xxx series aluminum alloys, 7xxx series aluminum alloys, and certain 8xxx aluminum alloys) can be subjected to a natural aging process and / or an artificial aging process. As described herein, a natural aging process includes storing the age-hardenable aluminum alloys at a temperature of about room temperature for a period of time to provide the age-hardened aluminum alloys in a T1 temper, a T2 temper, a T3 temper, or a T4 temper. Optionally, the age-hardenable aluminum alloys can be subjected to an artificial aging process including heating the aluminum alloys to an elevated temperature that is less than the liquidus temperature of the aluminum alloy to provide the age-hardened aluminum alloys in a T5 temper, a T6x temper, a T7 temper, a T8x temper, or a T9 temper. In other examples, strain-hardenable aluminum alloys (e.g., Ixxx series aluminum alloys, 3xxx series aluminum alloys, 4xxx series aluminum alloys, 5xxxAttorney Docket No. 108050-1530445series aluminum alloys, and certain 8xxx series aluminum alloys) can be subjected to a strain hardening process to provide the strain-hardened aluminum alloys in an Hxx temper as described above. As described herein, a strain hardening process includes cold working and optionally annealing the strain-hardenable aluminum alloys to provide the strain-hardened aluminum alloys in an H temper, such as an Hxl temper, an Hx2 temper, an Hx3 temper, an Hx4 temper, an Hx5 temper, an Hx6 temper, and Hx7 temper, an Hx8 temper, or an Hx9 temper.

[0103] The coated aluminum alloy can be fabricated into an aluminum alloy product, including an aluminum alloy plate, sheet, or shate. In some examples, the alloy can be fabricated into an aluminum alloy sheet including the graft copolymer coating described herein having any desired functionality. In some examples, the alloy can be fabricated into a shaped product formed from any aluminum alloy sheet described herein and including any coating layer formed from a graft copolymer pretreatment composition as described herein. In some examples, the aluminum alloy is a shaped product formed from any aluminum alloy sheet described herein and includes any graft copolymer coating described herein, wherein the shaped product is joined to another product formed from a different alloy or a different metal (e.g., a second alloy or a second metal). In some non-limiting examples, the aluminum alloy and the second metal and / or alloy are bonded to form a joint of any suitable configuration, including lap, edge, butt, T-butt, hem, T-edge, and the like.

[0104] The disclosed crosslinked graft copolymer coatings and methods tailor the surface characteristics of aluminum and aluminum alloys. Aluminum alloys that can benefit from the protective coating layers disclosed herein include those used in the motor vehicle industry (e.g., in automotive joints), manufacturing applications, electronics applications, industrial applications, and others. Optionally, the alloy is a part of a joined structure such as, for example, an auto skin such as doors, hoods fenders, and the like, as well as the chassis of an automobile or other motor vehicle. The auto skin and / or chassis can be in the body in white stage or painted.Methods of Use

[0105] The disclosed aluminum alloy products provided in the tempers described herein may be incorporated into existing processes and lines for production of aluminum alloy products, such as cold formed or warm formed aluminum products, as hot forming may denature the pretreatment composition (for example, cold formed automotive skinAttorney Docket No. 108050-1530445applications), thereby improving the processes and the resulting products in a streamlined and economical manner. The systems and methods for performing the forming processes and producing the products described herein are included within the scope of the disclosure.

[0106] The described aluminum alloy products and processes can be advantageously employed in the transportation industry, including, but not limited to, automotive manufacturing, truck manufacturing, manufacturing of ships and boats, manufacturing of trains, airplanes and spacecraft manufacturing. Some non-limiting examples of the automotive parts include floor panels, rear walls, rockers, motor hoods, fenders, roofs, door panels, B-pillars, body sides, rockers, or crash members. The term “automotive” and the related terms as used herein are not limited to automobiles and include various vehicle classes, such as, automobiles, cars, buses, motorcycles, marine vehicles, off highway vehicles, light trucks, trucks, or lorries. However, aluminum alloy products are not limited to automotive parts; other types of aluminum products manufactured according to the processes described in this application are envisioned. For example, the described processes can be advantageously employed in manufacturing of various parts of mechanical and other devices or machinery, including weapons, tools, bodies of electronic devices, and other parts and devices.

[0107] The aluminum alloy products and processes described herein can also be used in electronics applications, to prepare, for example, external and internal encasements. For example, the alloys and methods described herein can also be used to prepare housings for electronic devices, including mobile phones and tablet computers. In some examples, the alloys can be used to prepare housings for the outer casing of mobile phones (e.g., smart phones) and tablet bottom chassis.EXAMPLES

[0108] The following examples will serve to further illustrate the present disclosure without, however, constituting any limitation thereof. On the contrary, it is to be clearly understood that resort may be had to various embodiments, modifications, and equivalents thereof which, after reading the description herein, may suggest themselves to those skilled in the art without departing from the spirit of the invention.Attorney Docket No. 108050-1530445Example 1: Coating Metal Products with the Pretreatment SolutionAnalytical Instruments and Methods:

[0109] XRF analysis of dry fdm thicknesses. The thickness was estimated based on the measured P content using a calibration. Instrument: Thermo Scientific™ ARL™ OPTIM'X WDXRF Spectrometer The calibration is based on atomically flat surfaces with known coating thickness (measured by ellipsometry). Direct measurement of EDT surfaces using ellipsometry is not feasible due to the rough surface.

[0110] Pin-on-disc sliding distance via nanotribometer . TTX, STeP - NTR3instrument (Nano Tribometer, Anton Paar GmbH, Graz, Austria) together with either ST-S (maximum normal and friction loads, Fn, Ft = 100 mN) or HL-S (maximum Fn, Ft = 1 N) cantilevers were used for friction measurements. The nanotribology tests were performed on polymer coated silicon / alumina wafers using 2 mm diameter steel 100Cr6 balls at 300 mN (using an HL-S cantilever) loads. Sliding distance was 2 mm at 0.8 Hz (maximum linear speed 5 mm / s) over 500 cycles. No additional lubricant was used.Coating Procedures:[OHl] Roll coating was performed to evaluate graft copolymer coatings applied to aluminum oxide layers on silicon wafers as model substrates. Roll-coated substrates (e.g., aluminum substrates, such as 6170 aluminum alloy sheets pretreated with EDT, a tetrahydroacridine derivative) were roll-coated with PEGMEMA-co-HEMA-P (see structure below), cured for about 1.5 seconds at 250 °C and 13 seconds at 60-100 °C and cooled to room temperature (up to 50 hours) (Sample 1). PEGMEMA-co-HEMA-P used for the example was prepared from PEGMEMA having a Mn of 950 Da. However, it should be clear that other substrates and coatings are contemplated herein, as discussed above. The control was a roll-coated substrate (e.g., aluminum substrates, such as 6170 aluminum alloy sheets pretreated with EDT, a tetrahydroacridine derivative) roll-coated with PEGMEMA-co-HEMA-P), crosslinked with zirconium.P(PEGMEMA950-co-HEMA-P)Attorney Docket No. 108050-1530445

[0112] Figure 3 is a graph showing dry polymer film thickness before and after rinsing for the Control and Example 1. As illustrated, surprisingly, Example 1 maintained excellent residual film thickness, even without an external crosslinking agent.Example 2

[0113] Two control samples were prepared. The first contained no pretreatment composition applied over an aluminum alloy sheet (e.g. uncoated aluminum alloy), and is labelled control 1. The second control contained a crosslinked graft copolymer pretreatment composition as discussed herein applied over the aluminum alloy using 18 vol.% EtOH as a solvent.

[0114] Sample 1 was prepared by coating the aluminum alloy article with the crosslinked graft copolymer pretreatment composition using 18 vol.% EtOH as a solvent, and also contained a (6-Phosphonohexyl) phosphonic acid adhesion promoter.

[0115] Sample 2 was prepared by coating the aluminum alloy article with the crosslinked graft copolymer pretreatment composition using water as a solvent (less than 1 wt.% EtOH), a (6-Phosphonohexyl) phosphonic acid adhesion promoter, and a surfactant available as BYK345.

[0116] The samples were then bonded to a second aluminum alloy article using a commercial adhesive, and subjected to a salt fog spray bond durability test (Neutral Salt Spray) at 43 °C and 98% relative humidity. As shown in FIGS. 4 and 5, the samples performed well, and met the parameters of less than 40% initial strength loss as compared to the controls. Therefore, as discussed above, in embodiments, the adhesion promoter and / or surfactant may improve the bond strength to the pretreatment composition discussed herein.

[0117] However, as discussed above, it should be clear that the crosslinked graft copolymer pretreatment may not need any adhesion promoter or surfactant, in embodiments, as the crosslinked graft copolymer pretreatment may provide the one or more surface properties discussed above (see, e.g. FIG. 3).ILLUSTRATIONS OF SUITABLE COMPOSITIONS, PRODUCTS, AND METHODS

[0118] As used below, any reference to a series of aspects (e.g., “Aspects 1-4”) or nonenumerated group of aspects (e.g., “any previous or subsequent aspect”) is to be understood as a reference to each of those aspects disjunctively (e.g., “Aspects 1-4” is to be understood as “Aspects 1, 2, 3, or 4”).Attorney Docket No. 108050-1530445

[0119] Aspect 1 : A pretreated metal product, comprising an aluminum alloy product having a surface, and a crosslinked graft copolymer pretreatment composition bonded to the surface of the aluminum alloy product, the crosslinked graft copolymer pretreatment composition comprising, a polymer backbone, at least one surface binding or bonding moiety attached to the polymer backbone and configured to bind or bond the polymer backbone to a first surface of a metal product, at least one functional moiety attached to the polymer backbone and configured to provide at least a first surface functionalization to the first surface of the metal product, and wherein the at least one functional moiety, the at least one surface binding or bonding moiety, or both the at least one functional moiety and the at least one surface binding or bonding moiety are directly crosslinked to a further one of the at least one functional moiety or at least one surface binding or bonding moiety.

[0120] Aspect 2: The product of aspect 1, wherein the crosslinked graft copolymer pretreatment composition contains less than 1 wt.% external crosslinking agents, based upon the weight of the crosslinked graft copolymer pretreatment composition.

[0121] Aspect 3: The product of aspect 1 or 2, wherein the crosslinked graft copolymer pretreatment composition contains less than 0.1 wt.% external crosslinking agents, based upon the weight of the crosslinked graft copolymer pretreatment composition.

[0122] Aspect 4: The product of any one of aspects 1 to 3, wherein the at least one surface binding or bonding moiety comprises a phosphonate group, a phosphate group, a phosphoryl group, a carboxyl group, a catechol group, or a trialkoxysilyl group.

[0123] Aspect 5: The product of any one of aspects 1 to 4, wherein the at least one surface binding or bonding moiety is crosslinked to the further one of the at least one surface binding or bonding moiety.

[0124] Aspect 6: The product of any one of aspects 1 to 5, wherein the direct crosslinkage comprises an anhydride bond between two of the at least one surface binding or bonding moiety.

[0125] Aspect 7: The product of any one of aspects 1 to 6, wherein the polymer backbone is poly(methyl methacrylate), poly(ethyl methacrylate), poly(ethyl acrylate), polyacrylonitrile, polyethylene, polypropylene, polystyrene, poly(vinyl chloride), poly(vinyl acetate), poly(vinyl alcohol), polybutadiene, polyisoprene, polychloroprene, or any combination thereof.

[0126] Aspect 8: The product of any one of aspects 1 to 7, wherein the at least one functional moiety comprises a polymer side chain that provides a lubricating function.Attorney Docket No. 108050-1530445

[0127] Aspect 9: The product of any one of aspects 1 to 8, wherein the at least one functional moiety comprises a humectant.

[0128] Aspect 10: The product of any one of aspects 1 to 9, wherein the at least one functional moiety comprises a weld promoter.

[0129] Aspect 11 : The product of any one of aspects 1 to 10, wherein the at least one functional moiety comprises a corrosion inhibitor.

[0130] Aspect 12: The product of any one of aspects 1 to 11, further comprising at least one second functional moiety, wherein the at least one second functional moiety comprises an adhesion promoter, a polymer side chain that provides a lubricating function, a humectant, a weld promoter, or a corrosion inhibitor.

[0131] Aspect 13: The product of any one of aspects 1 to 12, wherein the pretreated metal product exhibits a sliding distance of greater than 50 cm at 300 mN, as measured using a nanotribometer.

[0132] Aspect 14: A method of pretreating at least a portion of a metal surface, comprising: applying a graft copolymer pretreatment composition to at least the portion of the metal surface, the graft copolymer pretreatment composition comprising a polymer backbone, at least one surface binding or bonding moiety attached to the polymer backbone and configured to bind or bond the polymer backbone to a first surface of a metal product, at least one functional moiety attached to the polymer backbone and configured to provide at least a first surface functionalization to the first surface of the metal product; and crosslinking the at least one functional moiety, the at least one surface binding or bonding moiety, or both the at least one functional moiety and the at least one surface binding or bonding moiety directly to a further one of the at least one functional moiety or at least one surface binding or bonding moiety.

[0133] Aspect 15: The method of aspect 14, wherein crosslinking comprises drying the graft copolymer pretreatment composition at a temperature of greater than or about 80 °C for greater than or about 5 minutes.

[0134] Aspect 16: The method of aspect 14 or 15, wherein crosslinking comprises drying the graft copolymer pretreatment composition at a temperature of greater than or about 100 °C for greater than or about 2 minutes.

[0135] Aspect 17: The method of any one of aspects 14 to 16, wherein crosslinking comprises curing the graft copolymer pretreatment composition at a temperature of about 60 °C to about 250 °C for less than or about 20 seconds.Attorney Docket No. 108050-1530445

[0136] Aspect 18: The method of any one of aspects 14 to 17, wherein the graft copolymer pretreatment composition comprises a residual thickness of greater than 200 nm.

[0137] Aspect 19: The method of any one of aspects 14 to 18, wherein the graft copolymer pretreatment composition comprises a residual thickness of greater than 250 nm.

[0138] Aspect 20: A pretreated metal product of any one of claims 1 to 13 or formed according to any one of methods 14 to 19.

[0139] All patents, patent applications, publications, and abstracts cited above are incorporated herein by reference in their entirety. Reference has been made in detail to various embodiments of the disclosed subject matter, one or more examples of which were set forth above. Each example was provided by way of explanation of the subject matter, not limitation thereof. In fact, it will be apparent to those skilled in the art that various modifications and variations may be made in the present subject matter without departing from the scope or spirit of the disclosure. For instance, features illustrated or described as part of one example, may be used with another example to yield a still further example.

Claims

Attorney Docket No. 108050-1530445WHAT IS CLAIMED IS:

1. A pretreated metal product, comprising:an aluminum alloy product having a surface, anda crosslinked graft copolymer pretreatment composition bonded to the surface of the aluminum alloy product, the crosslinked graft copolymer pretreatment composition comprising,a polymer backbone,at least one surface binding or bonding moiety attached to the polymer backbone and configured to bind or bond the polymer backbone to a first surface of a metal product,at least one functional moiety attached to the polymer backbone and configured to provide at least a first surface functionalization to the first surface of the metal product, andwherein the at least one functional moiety, the at least one surface binding or bonding moiety, or both the at least one functional moiety and the at least one surface binding or bonding moiety are directly crosslinked to a further one of the at least one functional moiety or at least one surface binding or bonding moiety.

2. The pretreated metal product of claim 1, wherein the crosslinked graft copolymer pretreatment composition contains less than 1 wt.% external crosslinking agents, based upon the weight of the crosslinked graft copolymer pretreatment composition.

3. The pretreated metal product of claim 2, wherein the crosslinked graft copolymer pretreatment composition contains less than 0.1 wt.% external crosslinking agents, based upon the weight of the crosslinked graft copolymer pretreatment composition.

4. The pretreated metal product of claim 1, wherein the at least one surface binding or bonding moiety comprises a phosphonate group, a phosphate group, a phosphoryl group, a carboxyl group, a catechol group, or a trialkoxysilyl group.

5. The pretreated metal product of claim 4, wherein the at least one surface binding or bonding moiety is crosslinked to the further one of the at least one surface binding or bonding moiety.Attorney Docket No. 108050-15304456. The pretreated metal product of claim 5, wherein the direct crosslinkage comprises an anhydride bond between two of the at least one surface binding or bonding moiety.

7. The pretreated metal product of claim 1, wherein the polymer backbone is poly(methyl methacrylate), poly(ethyl methacrylate), poly(ethyl acrylate), polyacrylonitrile, polyethylene, polypropylene, polystyrene, poly(vinyl chloride), poly(vinyl acetate), poly(vinyl alcohol), polybutadiene, polyisoprene, polychloroprene, or any combination thereof.

8. The pretreated metal product of claim 1, wherein the at least one functional moiety comprises a polymer side chain that provides a lubricating function.

9. The pretreated metal product of claim 1, wherein the at least one functional moiety comprises a humectant.

10. The pretreated metal product of claim 1, wherein the at least one functional moiety comprises a weld promoter and / or a corrosion inhibitor.

11. The pretreated metal product of claim 1, further comprising at least one second functional moiety, wherein the at least one second functional moiety comprises an adhesion promoter, a polymer side chain that provides a lubricating function, a humectant, a weld promoter, or a corrosion inhibitor.

12. The pretreated metal product of claim 1, wherein the crosslinked graft copolymer pretreatment composition further comprises an adhesion promoter, a surfactant, an antioxidant, or a combination thereof.

13. The pretreated metal product of claim 1, wherein the pretreated metal product exhibits a sliding distance of greater than 50 cm at 300 mN, as measured using a nanotribometer.

14. A method of pretreating at least a portion of a metal surface, comprising:applying a graft copolymer pretreatment composition to at least the portion of the metal surface, the graft copolymer pretreatment composition comprisinga polymer backbone,at least one surface binding or bonding moiety attached to the polymer backbone and configured to bind or bond the polymer backbone to a first surface of a metal product,Attorney Docket No. 108050-1530445at least one functional moiety attached to the polymer backbone and configured to provide at least a first surface functionalization to the first surface of the metal product; andcrosslinking the at least one functional moiety, the at least one surface binding or bonding moiety, or both the at least one functional moiety and the at least one surface binding or bonding moiety directly to a further one of the at least one functional moiety or at least one surface binding or bonding moiety.

15. The method of claim 14, wherein crosslinking comprises drying the graft copolymer pretreatment composition at a temperature of greater than or about 80 °C for greater than or about 5 minutes.

16. The method of claim 15, wherein crosslinking comprises drying the graft copolymer pretreatment composition at a temperature of greater than or about 100 °C for greater than or about 2 minutes.

17. The method of claim 14, wherein crosslinking comprises curing the graft copolymer pretreatment composition at a temperature of about 60 °C to about 250 °C for less than or about 20 seconds.

18. The method of claim 14, wherein the graft copolymer pretreatment composition comprises a residual thickness of greater than 200 nm.

19. The method of claim 18, wherein the graft copolymer pretreatment composition comprises a residual thickness of greater than 250 nm.

20. A pretreated metal product, formed according to the method of claim 14.

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