Coated films that demonstrate reduced fouling and methods of inhibiting fouling of an article component

Abstract

Coated antifouling films are provided comprising: (a) a flexible polymeric film having a first surface and an opposing second surface, (b) a metal oxide layer applied to the first surface; (c) a polymerization initiator chemically bonded to the metal oxide layer via reaction with reactive functional groups on the metal oxide layer; and (d) a hydrophilic polymeric coating layer prepared by a radical polymerization process from a monomer composition comprising at least one free radical polymerizable monomer having at least one hydrophilic functional group, wherein the polymeric coating layer is chemically bonded to and propagated from the polymerization initiator (c). Also provided are methods of preparing the antifouling coated film and methods of inhibiting fouling of an article component by a contaminant, comprising: (a) providing a coated antifouling film; and (b) adhesively applying the coated antifouling film described above to at least one surface of the component.

Description

COATED FILMS THAT DEMONSTRATE REDUCED FOULING AND METHODS OF INHIBITING FOULING OF AN ARTICLE COMPONENTRELATED APPLICATIONS

[0001] The present application claims the benefit of US Provisional Patent Application Serial Number 63 / 683,871 , titled “Coated Oil or Gas Operation Components that Demonstrate Reduced Fouling and Methods of Inhibiting Fouling of an Oil or Gas Operation Component”, filed August 16, 2024. The present application claims the benefit of US Provisional Patent Application Serial Number 63 / 683,884, titled “Anti-Fouling Filter or Membrane Coating for Enhanced Separation in Biomedical, Dairy, Beverage, and Liquid Filtration Applications”, filed August 16, 2024; The present application claims the benefit of US Provisional Patent Application Serial Number 63 / 683,891 , titled “Oil-Water Separation Assemblies and Methods of Separating an Oil-In-Water Aqueous Emulsion or Water-In-Oil Hydrocarbon Emulsion”, filed August 16, 2024; The present application claims the benefit of US Provisional Patent Application Serial Number 63 / 683,914, titled “Method for Surface- Initiated Polymerization on Surfaces and Coated Substrates Formed Thereby”, filed August 16, 2024, and incorporated by reference in their entireties.FIELD OF THE INVENTION

[0002] The present invention relates to coated films, the films having thin coatings that demonstrate superhydrophilicity and fouling resistance. The present invention is further related to methods of inhibiting fouling of article components.BACKGROUND OF THE INVENTION

[0003] Changing the surface energy of a substrate is of great value in many diverse industries and products, such as oil, gas and energy production, maritime industries, medical industries, optical industries, chemical manufacturing, food and beverage processing and the like. Depending on the needs and applications, substrate surfaces can be customized to exhibit hydrophilic, hydrophobic, oleophobic and oleophilic properties. Exceptionally hydrophilic surfaces are particularly desired in certain environments to prevent fouling of equipment by inorganic scale (e.g. calcium carbonate, barium sulfate,magnesium carbonate), fog such as aqueous fog, proteins, fats such as plant oils, lard, tallow and grease, tar, resins, aromatic hydrocarbons, alkanes, bitumens, waxes such as paraffinic compounds and / or asphaltene-type compounds.

[0004] Scientifically, liquids with lower surface tensions (e. g., oil with surface tensions < 30 mN / m) tend to wet solid surfaces (with specific surface energy) more than liquids with higher surface tensions (e. g., water with surface tension of 72.8 mN / m). Coated surfaces may be prepared to yield different contact angles for liquids with higher surface tensions compared to those with lower surface tensions.

[0005] A current solution to this problem of fouling of surfaces is through the use of fluorinated coatings that can resist significant adsorption of the organic fouling compounds. While these treatments are certainly effective for organic compounds, they have been found to increase the adsorption of inorganic scale. Furthermore, they contain perfluorinated compounds that are suspected to be hazardous such that they are especially unsuitable for food production equipment and are highly persistent in the environment.

[0006] Even more significant is that the hydrophilic coatings (e. g., polyethylene glycol- based coatings) that have been developed as anti-scale coatings cannot repel hydrocarbon-based contaminants, so there is currently no effective strategy to repel both hydrocarbon and inorganic fouling compounds with surface treatments.

[0007] The modification of substrate surfaces with superhydrophilic polymers has also been proposed, using controlled radical polymerization (CRP) processes to dictate polymer architecture. Polymerization of hydrophilic monomers, in particular, (meth)acrylamide monomers that may provide such extreme hydrophilicity has historically been difficult to achieve via controlled radical polymerization processes such as ATRP, likely due to the exceptionally high rate of polymerization of these monomers as well as their chemical interaction with the copper-based catalysts typically used for such polymerization processes.

[0008] In addition, running these polymerizations in water adds another significant challenge due to the fact that ATRP initiators are usually activated alkyl halide compounds, which are highly prone to hydrolysis and rapidly lose their ability to control polymerization. When these polymerizations are conducted on surfaces in an aqueous medium, the ratio of initiating groups to water is many orders of magnitude in favor of water, making hydrolysisreactions far more likely than propagation of a polymer from an initiating site. Hence, the reported attempts of ATRP of (meth)acrylamide polymers in water are scarce, and surface- propagated polymerizations of them are absent from the literature to our knowledge.

[0009] Modifying the surfaces of substrates, including some modification methods that use CRP processes, tend to have drawbacks that make them unsuitable for many substrates because these processes typically employ solvents that are too aggressive, leading to degradation and / or swelling of a polymer substrate, or corrosion of a metal substrate caused by such solvents. For example, the most commonly used strategies for binding a polymerization initiator to a polymer surface use aggressive chemical attack to create functional groups (like hydroxyl, amine, etc.), followed by exposure to polar aprotic solvents such as diethyl ether, dichloromethane, etc., containing the initiator (for example, alphabromoisobutyryl bromide) and a base catalyst such as triethylamine.

[0010] These methodologies are too aggressive to be used on most polymers, excepting highly fluorinated or crosslinked aromatic polymers such as PTFE, PFA, polyimide and PEEK. Commonly used polymers such as polyamide, pebax, acrylics, polyesters, polyolefins, PVC, and the like, are rapidly degraded by the aforementioned processes.

[0011] Moreover, it may be difficult to modify or treat the surfaces of prefabricated vehicles and industrial equipment, especially if it is already deployed such as in a manufacturing or other industrial processing setting.

[0012] It would be desirable to provide coated films that demonstrate superhydrophilicity and fouling resistance, which can be adhesively applied to articles such as vehicles and industrial equipment components post-fabrication, and methods of inhibiting fouling of article components by both organic and inorganic contaminants.SUMMARY OF THE INVENTION

[0013] One aspect of the present invention provides coated antifouling films comprising:(a) a flexible polymeric film having a first surface and an opposing second surface, wherein the first surface comprises an activated surface formed by:(i) modifying the first surface of the flexible polymeric film via flame, corona discharge, argon plasma discharge, or chemical etching to form reactive functional groups on the first surface of the flexible polymeric film, or(ii) applying an activated layer comprising metal to the first surface of the flexible polymeric film to form reactive functional groups on the first surface of the flexible polymeric film;(b) an initiator layer comprising a polymerization initiator chemically bonded to the activated surface via reaction with the reactive functional groups on the activated surface; and(c) a hydrophilic polymeric coating layer prepared by a radical polymerization process from a monomer composition comprising at least one free radical polymerizable monomer having at least one hydrophilic functional group, wherein the hydrophilic coating layer is chemically bonded to and propagated from the polymerization initiator.

[0014] The invention further provides methods of preparing an antifouling coated film comprising:(a) forming an activated surface on a first surface of a flexible polymeric film having the first surface and an opposing second surface, wherein the activated surface is formed by:(i) modifying the first surface of the flexible polymeric film via flame, corona discharge, argon plasma discharge, or chemical etching to form reactive functional groups on the first surface of the flexible polymeric film, or(ii) applying an activated layer comprising metal to the first surface of the flexible polymeric film to form reactive functional groups on the first surface of the flexible polymeric film;(b) chemically bonding a polymerization initiator to the activated surface via reaction with the reactive functional groups on the activated surface to form an initiator layer;(c) contacting the initiator layer with an aqueous monomer composition comprising at least one free radical polymerizable monomer having at least one hydrophilic functional group;(d) allowing the monomers in the aqueous monomer composition to polymerize via a radical polymerization process to form a hydrophilic polymeric coating layer, wherein the hydrophilic polymeric coating layer is chemically bonded to and propagated from the polymerization initiator; and optionally(e) curing the hydrophilic polymeric coating layer by reaction of reactive functional groups in the hydrophilic polymeric coating layer.

[0015] The invention further provides methods of inhibiting fouling of an article component by a contaminant, comprising:(a) providing a coated antifouling film; and(b) adhesively applying the coated antifouling film described above to at least one surface of the article component.BRIEF DESCRIPTION OF THE DRAWINGS

[0016] FIG. 1 is a schematic illustration of a coated antifouling film of the present invention in the form of a sheet rolled into a coil.

[0017] FIG. 2 is a schematic illustration of coated antifouling films of the present invention in the form of planar sheets that may be stacked for purposes of storage or shipping.

[0018] FIG. 3 is a schematic illustration of a cross-sectional view of a coated antifouling film of the present invention.

[0019] FIG. 4 is a schematic illustration of a cross-sectional view of a portion of a coated antifouling film of the present invention.

[0020] FIG. 5 is a schematic illustration of a portion of a coated antifouling film of the present invention, with a removable backing layer applied to an adhesive layer.

[0021] FIG. 6 is a schematic illustration of the application of a coated antifouling film of the present invention to an article component.

[0022] FIGS. 7A, 7B and 7C schematically illustrate the application of the coated antifouling films of the present invention to article components in the form of boat hulls, culvert interior and pipeline interiors.

[0023] Note that the figures are not drawn to scale.DETAILED DESCRIPTION OF THE INVENTION

[0024] Other than in any operating examples, or where otherwise indicated, all numbers expressing quantities of ingredients, reaction conditions and so forth used in the specification and claims are to be understood as being modified in all instances by the term “about.” Accordingly, unless indicated to the contrary, the numerical parameters set forthin the following specification and attached claims are approximations that may vary depending upon the desired properties to be obtained by the present invention. At the very least, and not as an attempt to limit the application of the doctrine of equivalents to the scope of the claims, each numerical parameter should at least be construed in light of the number of reported significant digits and by applying ordinary rounding techniques.

[0025] Notwithstanding that the numerical ranges and parameters setting forth the broad scope of the invention are approximations, the numerical values set forth in the specific examples are reported as precisely as possible. Any numerical value, however, inherently contain certain errors necessarily resulting from the standard deviation found in their respective testing measurements.

[0026] Also, it should be understood that any numerical range recited herein is intended to include all sub-ranges subsumed therein. For example, a range of “1 to 10” is intended to include all sub-ranges between (and including) the recited minimum value of 1 and the recited maximum value of 10, that is, having a minimum value equal to or greater than 1 and a maximum value of equal to or less than 10.

[0027] As used in this specification and the appended claims, the articles "a," "an," and "the" include plural referents unless expressly and unequivocally limited to one referent.

[0028] The various aspects and examples of the present invention as presented herein are each understood to be non-limiting with respect to the scope of the invention.

[0029] As used in the following description and claims, the following terms have the meanings indicated below:

[0030] The terms "on", "appended to", "affixed to", "bonded to", "adhered to", or terms of like import means that the designated item, e.g., a coating, film or layer, is either directly connected to (in contact with) the object surface, or indirectly connected to the object surface, e.g., through one or more other coatings, films or layers.

[0031] While not intending to be bound by theory, the premise of the present invention is that if a highly hydrophilic polymer is first chemically bonded to and propagated from surfaces it can help prevent or even reverse fouling of the surface by contaminants, due to the strength of adsorption of water molecules to the surface. The surface, rendered hydrophilic by the polymer propagated therefrom, preferentially adsorbs water instead of any contaminants in a fluid stream with which the surface comes into contact. It has alsobeen determined that these polymers cannot be simply cast or adsorbed, or they will dissolve from the component surface; they must be chemically bound to the surface. Moreover, copolymerization with water-insoluble co-monomers to keep the polymer stable only creates slight hydrophilicity, which is not strongly attracted enough to water to resist / desorb the aforementioned contaminants.

[0032] The coated antifouling films 200 of the present invention are designed to offer a convenient method for providing antifouling properties to article components 400 such as industrial equipment article components as discussed below, by allowing for adhesive application of the films in the manner of a tape to a component surface post-fabrication, even in the field. Figures 7A, 7B and 7C are representative examples showing application of the coated antifouling films 200 to article components 400 in the form of boat hulls, culvert interior and pipeline interiors. Because the films are flexible and size-customizable, they are particularly suitable for application to large equipment components such as industrial equipment components in the field, very small component surfaces or surfaces that would be difficult to coat under conventional conditions due to their size, location or orientation. The films of the present disclosure differ from membranes (i. e., separation membranes) in that unlike membranes, the films are not typically porous or permeable to liquids or gases.

[0033] The coated antifouling films 200 of the present invention as shown in FIGS. 3 and 4 may be prepared by a method comprising:(a) forming an activated surface 204 on a first surface of a flexible polymeric film 202 having the first surface and an opposing second surface;(b) chemically bonding a polymerization initiator to the activated surface 204 via reaction with reactive functional groups on the activated surface 204 to form an initiator layer 206;(c) contacting the initiator layer 206 with an aqueous monomer composition comprising at least one free radical polymerizable monomer having at least one hydrophilic functional group;(d) allowing the monomers in the aqueous monomer composition to polymerize via a radical polymerization process to form a hydrophilic polymeric coating layer 208, wherein the hydrophilic polymeric coating layer 208 is chemically bonded to and propagated from the polymerization initiator; and optionally(e) curing the hydrophilic polymeric coating layer 208 by reaction of reactive functional groups in the hydrophilic polymeric coating layer.

[0034] The coated antifouling films 200 of the present invention comprise (a) a flexible polymeric film 202 having a first surface and an opposing second surface, as shown in FIGS. 3 and 4. By “flexible” is meant reversibly bendable and / or capable of being reversibly rolled into a coil. In certain examples, the polymeric film may be conformable to the topography of a component surface to be covered. Non-limiting examples of materials suitable for use as the flexible polymeric film 202 include polyethylene terephthalate (PET), a polyamide, a polyamide-polyether block copolymer, a poly(meth)acrylate, a polyester, a polyolefin, a polyisoprene, a polyurethane, a polyester-polyurethane copolymer, a polyimide, a cycloolefin polymer, a polyether ketone, a polysulfone, a polycarbonate and a polysiloxane. The materials, as noted above, are typically non-porous and / or impermeable to liquids and gases, and are thus distinguished from membranes as membranes are typically porous (i.e. , gas permeable and / or liquid permeable). Note that the phrase “and / or” when used in a list in this disclosure is meant to encompass alternative embodiments including each individual component in the list as well as any combination of components. For example, the list “A, B, and / or C” is meant to encompass seven separate embodiments that include A, or B, or C, or A + B, or A + C, or B + C, or A + B + C.

[0035] The flexible polymeric film 202 may be in the form of a planar plate or sheet, having two opposing surfaces. The thickness of the flexible polymeric film depends on the nature of the final product, but typically ranges, for example, from 1 to 5000 microns, such as 10 to 1000 microns, or 500 to 1000 microns, or 50 to 500 microns, or 50 to 100 microns, or 1 to 100 microns. Likewise, the width and length may be adjusted as desired for a given application. For example, the flexible polymeric film may have a width of 0.5 to 10 m, such as 1 to 10 m, or 1 to 5 m, or 1 to 3 m, and a length of 0.5 to 250 m, or 0.5 to 100 m, or 1 to 30 m. The flexible polymeric film may also be cut to size for customization, depending on the intended application.

[0036] The first surface of the flexible polymeric film 202 comprises an activated surface 204 (FIGS. 3 and 4). The activated surface 204 may be formed by:(i) modifying the first surface of the flexible polymeric film 202 such as via flame, corona discharge, argon plasma discharge, or chemical etching (particularly using a NaOHor KOH solution), to form reactive functional groups, such as hydroxyl functional groups, on the first surface of the flexible polymeric film 202, or(ii) applying an activated layer comprising metal to the first surface of the flexible polymeric film 202 to form reactive functional groups on the first surface of the flexible polymeric film 202.

[0037] When the activated surface 204 is formed by applying an activated layer comprising metal to the first surface of the flexible polymeric film 202, the activated layer may comprise one or more of Ti, Cr, Al, Ta, Nb, Ni, silver oxide, gold oxide, palladium oxide, platinum oxide, rhodium oxide, iridium oxide, tantalum oxide, aluminum oxide, copper oxide, titanium oxide, iron oxide, and chromium oxide.

[0038] The activated layer comprising the metal may be applied to the flexible polymeric film 202 via chemical vapor deposition (CVD), physical vapor deposition (PVD), electron beam evaporation, or electroless deposition from solution to form the activated surface 204.

[0039] At this stage in the process, a removable protective layer 210 may be applied to the activated surface 204, as shown in FIG. 4. The application of the protective layer 210 allows for storage of the films and / or shipping to a worksite, after which the protective layer 210 may be subsequently removed and the remainder of the process may be conducted. As such, the final preparation steps of the antifouling coated films may be conducted at a later time or even onsite in the field.

[0040] The coated antifouling films 200 of the present invention further comprise (b) an initiator layer 206 comprising a polymerization initiator chemically bonded to the activated surface 204 via reaction with the reactive functional groups on the activated surface 204 to form an initiator layer 206. The polymerization initiator may be bonded to the activated surface 204 using conventional techniques, including physical vapor deposition (PVD) or chemical vapor deposition (CVD) such as iCVD, to ensure a thin layer of molecular dimensions.

[0041] Any initiators known in the art for radical polymerization processes, in particular, living (i.e., controlled radical) polymerization processes are suitable, provided they may be chemically bonded to the activated surface 204 by reaction with reactive functional groups on the activated surface 204. Organosilicon compounds may serve as an initiator. Suitable organosilicon compounds include alkoxysilane functional compounds such as (3-trimethoxysilyl)propyl-2-bromo-2-methylpropionate. Also suitable are organosilicon- containing compounds with ethylenically unsaturated groups, such as (3- trimethoxysilyl)propyl (meth)acrylate, and (3-trimethoxysilyl)propyl (meth)acrylamide. Also useful are organophosphorus acids chemically bonded to the substrate surface, wherein the organo portion of the organophosphorus acid contains an initiator moiety such as a halide group (for example, chloride, bromide, and / or iodide). Other halide-containing compounds including alkyl, aryl or acyl halide compounds, such as benzyl halide, 2- halopropionitrile and oc-haloisobutyryl halide, in particular, oc-bromoisobutyryl bromide, are also suitable. Azo-initiators such as azobisbutyronitrile (AIBN), 1 ,1 ’- azobis(cyclohexanecarbonitrile), and 4,4-azobis (4-cyanopentanoic acid), and K2S2O8, as used in addition-fragmentation chain transfer (RAFT) polymerization processes may also be employed.

[0042] The coated antifouling films 200 of the present invention further comprise (c) a hydrophilic polymeric coating layer 208, as shown in FIG. 3. The polymeric coating layer 208 is chemically bonded to and propagated from the polymerization initiator in the initiator layer 206.

[0043] The hydrophilic polymeric coating layer 208 may be prepared from an aqueous monomer composition comprising at least one free radical polymerizable monomer having at least one hydrophilic functional group. Any monomer capable of free-radical polymerization may be used in the aqueous monomer composition. Examples of particularly suitable monomers include hydrophilic styrene functional monomers, acrylonitrile, (meth)acrylamide functional monomers, 4-vinylpyridine, sodium 4- vinylbenzenesulfonate, and monomers that are quaternized with a halide (e. g., chloride or fluoride) or have functional groups that are capable of being quaternized with a halide after polymerization. Other suitable monomers include dienes, alkylvinyl monomers or allyl ethers.

[0044] In a particular example, the hydrophilic polymeric coating layer 208 may be prepared from an aqueous monomer composition comprising at least 50 percent by weight, based on the total weight of monomers in the monomer composition, of at least one (meth)acrylamide monomer having at least one ionic functional group. For example, the hydrophilic polymeric coating layer 208 may be formed from an aqueous monomercomposition comprising at least one of a (meth)acrylamide halide salt, 2- aminoethylmethacrylamide hydrochloride halide salt, N,N’-(3-(dimethylamino)propyl) methacrylamide, N,N-(3-dimethylamino)propyl)-methacryloylaminobutyl sulfonate, N,N-(3- dimethylamino)propyl)-methacryloylaminopropyl sulfonate, 2-acrylamidopropane-2- methyl-1 -propane sulfonic acid salt, [3-(methacryloylamino)propyl]trimethylammonium chloride, [3-(acryloylamino)propyl]trimethylammonium chloride, N,N’- dimethyl(meth)acrylamide and salts thereof, and 3-[(3- (meth)acrylamidopropyl)dimethylammonio]propanoate. The polymeric coating layer 208 may comprise a homopolymer of any of the above monomers, or may comprise a copolymer, such as a block copolymer, of two or more of the above monomers, designed to provide both hydrophilic and additional antifouling properties.

[0045] The hydrophilic polymeric coating layer 208 is typically prepared via a radical polymerization process, such as a controlled radical polymerization (CRP) or “living” process; i.e., a chain-growth polymerization that propagates with essentially no chain transfer and essentially no chain termination. The molecular weight of a polymer prepared by CRP can be controlled by the stoichiometry of the reactants, i.e., the initial concentration of monomer(s) and initiator(s). In addition, CRP also provides polymers having characteristics including, for example, narrow molecular weight distributions, e. g., PDI values less than 2.5, and well-defined polymer chain architecture, e. g., block copolymers and alternating copolymers. As used herein, the term “controlled radical polymerization” and related terms such as “controlled radical polymerization process” includes, but is not limited to, atom transfer radical polymerization (ATRP), single electron transfer polymerization (SETP), reversible addition-fragmentation chain transfer (RAFT), and nitroxide-mediated polymerization (NMP).

[0046] In forming the coated antifouling films 200 of the present invention, the activated surface 204 on the flexible polymeric film 202 is first contacted with initiator molecules to chemically bond the initiator to the activated surface 204 via reaction with the reactive functional groups on the activated surface 204 to form an initiator layer 206. The initiator layer 206 is then contacted with the monomer composition described above and a CRP catalyst, and polymerized under CRP conditions in an aqueous medium to form a layer of (meth)acrylamide-containing polymer, for example.

[0047] In an example using ATRP, the activated surface 204 having reactive functional groups is contacted with a compound containing in a terminal portion a functional group reactive with the reactive functional groups on the activated surface 204, and in a second terminal portion, an initiator for ATRP. A self-assembled monolayer (SAM) is formed from the compound bonded to the activated surface 204, with the initiator extending outwardly from the activated surface 204 and forming the initiator layer 206. The SAM is contacted with an aqueous mixture comprising the monomer composition and an ATRP catalyst, and the monomer composition is polymerized to form a layer 208 of (meth)acrylamide- containing polymer, for example, on the surface, chemically bonded to and propagated from the polymerization initiator.

[0048] The ATRP polymerization catalyst is typically a transition metal compound, which participates in a reversible redox cycle with the initiator; and a ligand, which coordinates with the transition metal compound. The ATRP process is described in further detail in International Patent Publication No. WO 98 / 40415 and U.S. Pat. Nos. 5,807,937, 5,763,548 and 5,789,487 which are incorporated herein by reference.

[0049] Catalysts that may be used in the ATRP preparation include any transition metal compound. It is preferred that the transition metal compound not form direct carbon-metal bonds with the polymer chain. Transition metal catalysts useful in the present invention may be represented by the following general formula:Mn+Xn wherein M is the transition metal, n is the formal charge on the transition metal having a value of from 0 to 7, and X is a counter-ion or covalently bonded component. Examples of the transition metal M include, but are not limited to, Cu, Fe, Au, Ag, Hg, Pd, Pt, Co, Mn, Ru, Mo, Nb and Zn. Examples of X include, but are not limited to, halide, hydroxy, oxygen, Ci-C6alkoxy, cyano, cyanato, thiocyanato and azido. A preferred transition metal is Cu(l) and X is preferably halide, e.g., chloride. Accordingly, a preferred class of transition metal catalyst is the copper halides, e.g., Cu(l)CI. It is also preferred that the transition metal catalyst contain a small amount, e.g., 1 mole percent, of a redox conjugate, for example, Cu(ll)Cl2, when Cu(l)CI is used. Additional catalyst useful in preparing the pigment dispersant are described in U.S. Pat. No. 5,807,937 at column 18, lines 29 through 56 which patent is incorporated herein by reference in its entirety. Redox conjugates aredescribed in further detail in U.S. Pat. No. 5,807,937 at column 1 1 , line 1 through column 13, line 38 which patent is incorporated herein by reference in its entirety.

[0050] Ligands that may be used in ATRP for preparation of the polymerization catalyst include compounds having one or more nitrogen, oxygen, phosphorus and / or sulfur atoms, which can coordinate to the transition metal catalyst compound, e. g., through sigma and / or pi bonds. Classes of useful ligands include tertiary aliphatic amines, unsubstituted and substituted pyridines and bipyridines; porphyrins; cryptands; crown ethers; e.g., 18-crown- 6; polyamines, e.g., ethylenediamine; glycols, e.g., alkylene glycols, such as ethylene glycol; carbon monoxide; and coordinating monomers, e.g., styrene, acrylonitrile and hydroxyalkyl (meth)acrylates.

[0051] As used herein and in the claims, the term "(meth)acrylate" and similar terms refer to acrylates, methacrylates and mixtures of acrylates and methacrylates; similarly for (meth)acrylamide. A preferred class of ligands are the substituted bipyridines, e.g., 4,4'- dialkyl-bipyridyls. Additional ligands that may be used in preparing pigment dispersant are described in U.S. Pat. No. 5,807,937 at column 18, line 57 through column 21 , line 43 which patent is incorporated herein by reference in its entirety.

[0052] The reducing agent may be any reducing agent capable of reducing the transition metal catalyst from a higher oxidation state to a lower oxidation state, thereby reforming the catalyst activator state. Such reducing agents include, for example, SO2, sulfites, bisulfites, thiosulfites, mercaptans, hydroxylamines, hydrazine (N2H4), phenylhydrazine (Ph-NHNH2), hydrazones, hydroquinone, food preservatives, flavonoids, beta carotene, vitamin A, a-tocopherols, vitamin E, propyl gallate, octyl gallate, BHA, BHT, propionic acids, ascorbic acid, sorbates, reducing sugars, sugars comprising an aldehyde group glucose, lactose, fructose, dextrose, potassium tartrate, nitriles, nitrites, dextrin, aldehydes, glycine, and transition metal salts. Water-soluble reducing agents are particularly suitable.

[0053] The above-mentioned ingredients are typically dissolved or suspended in an aqueous medium, which may include in minor portions a diluent such as an organic solvent; for example, acetone or methanol. Also, solvents such as those containing oligo ethylene oxide and propylene oxide groups, such as diethylene glycol, diethylene glycol monomethyl ether and tripropylene glycol monomethyl ether may be used in minor portions. Such solvents may boost the activity of the catalyst. The concentration of the radicallypolymerizable monomers is typically from 5 to 70 percent by weight based on total weight of solution. The molar ratio of catalyst to monomer ranges from 1 :5 to 1 :500, such as 1 :20 to 1 OO; the molar ratio of ligand to catalyst ranges from 1 :2 to 1 M OO, such as 1 :2 to 1 :5. The molar ratio of reducing agent to catalyst is from 1 :0.1 to 10 such as 1 :0.5 to 2.

[0054] The aqueous solution of the radically polymerizable monomer composition can be applied to the initiator-coated film (i. e., the initiator layer 206) by conventional means such as dipping, rolling, spraying, printing, stamping or wiping to ensure uniform coating of the surface. The solution may be applied to the entire surface or over a portion thereof, such as in a predetermined pattern using a mask. The formation of the ATRP film or coating can occur at temperatures in the range of -10 to 150°C and at pressures of 1 -100 atmospheres, usually at ambient temperature and pressure. By “ambient” conditions is meant without the application of heat or other energy; for example, when a curable composition undergoes a thermosetting reaction without baking in an oven, use of forced air, irradiation, or the like to prompt the reaction, the reaction is said to occur under ambient conditions. Usually, ambient temperature ranges from 60 to 90 °F (15.6 to 32.2 °C), such as a typical room temperature, 72°F (22.2°C). The time for conducting the ATRP can vary depending on the thickness of the film desired. The hydrophilic polymeric coating layer 208 typically has a thickness greater than 50 nm and less than 2.5 microns, such as less than 2 microns, or less than 1 micron, or even less than 100 nm. Such thick coating layers of aqueous CRP- generated (meth)acrylamide polymer coating layers have not been achieved previously; the thickness of the coating contributes to lubricity. The thickness of the film can be monitored by Quartz Crystal Microgravometric (QCM) measurement and the time for the ATRP is typically from 30 to 600 minutes. After ATRP, the coated film is removed from any remaining solution by rinsing with a polar solvent and drying the coated substrate.

[0055] When the initiator layer 206 of the initiator-coated film is exposed to the aqueous solution of the radically polymerizable monomer composition and subjected to ATRP conditions, the monomers contained therein form covalent bonds with each other and with the initiator groups that are bonded to the surface of the substrate. As mentioned above, the resultant hydrophilic polymeric coating layer 208 is relatively thick (compared to typical surface ATRP processes) with strong adhesion to the substrate. The resulting polymer has a low polydispersity index because chain transfer reactions are minimized. Lowerpolydispersity indices enable the molecular weight of the polymer to be controlled and optimized for the particular application intended.

[0056] The process may further include subjecting the coated antifouling film 200 to heat or UV radiation to effect curing of any reactive functional groups on the polymers of the hydrophilic polymeric coating layer 208. Such curing may further ensure a robust and durable polymeric coating layer 208.

[0057] The term “cure”, “cured” or similar terms, as used in connection with a cured or curable composition, e.g., a “cured composition” of some specific description, means that at least a portion of any polymerizable and / or cross-linkable components that form the curable composition is polymerized and / or crosslinked. Additionally, curing of a composition refers to subjecting said composition to curing conditions such as heating or exposure to actinic radiation, depending on the chemistry, leading to the reaction of any reactive functional groups in the composition. The term “at least partially cured” means subjecting the composition to curing conditions, wherein reaction of at least a portion of the reactive groups of the composition occurs. The composition can be subjected to curing conditions as necessary depending on the composition of the coating layers, such that a substantially complete cure is attained and wherein further curing results in no significant further improvement in physical properties, such as hardness.

[0058] The resultant coated films are hydrophilic, even superhydrophilic, demonstrating lubricity, and the hydrophilic polymeric coating layers 208 serve as easy clean coatings and antifouling coatings. The hydrophilic polymeric coating layer 208 often demonstrates a water contact angle less than 10°, typically less than 5°, and retains a contact angle of less than 10° after immersion in phosphate buffered (approximate pH of 7.4) aqueous saline solution at 22°C for a period of 28 days, often greater than 28 days. Additionally, the hydrophilic polymeric coating layer 208 will not lose its hydrophilic or lubricious properties under these conditions. By “superhydrophilicity” is meant a high degree of hydrophilicity, or attraction to water; in superhydrophilic materials, the contact angle of water is less than 10°, often less than 5°, even equal to 0°.

[0059] The coated antifouling film 200 may further comprise (d) an adhesive layer 212 applied to the opposing second surface of the flexible polymeric film 202; i. e., the surface opposite the activated surface 204. When the adhesive layer 212 comprises a pressuresensitive adhesive, the coated antifouling film 200 may further comprise (e) a removable backing layer 214 applied to the adhesive layer 212. FIG. 5 illustrates this portion of a coated antifouling film; in particular, the adhesive layer 212 and the removable backing layer 214. As shown in FIG. 6, the coated antifouling film 200 may then be applied in the manner of a tape via the adhesive to any article component 400, including a prefabricated component, to inhibit fouling thereof. Such a coated antifouling film with an adhesive layer 212 allows for applying the coated film to components onsite in the field. Alternatively, an adhesive may be applied to a surface of the component 400, such as by spraying, and the coated antifouling film 200 applied to the adhesive on the component surface. Multiple pieces or strips of the coated antifouling film 200 may be applied to a component surface as shown in FIG. 7A such that edges of adjacent pieces abut each other or overlap each other to ensure complete coverage of the component surface. The seams along adjacent abutting edges may be sealed if desired using any suitable sealant known in the art.

[0060] The coated antifouling films 200 of the present invention may be produced in the form of a planar sheet, allowing for stacking of multiple sheets as demonstrated in FIG. 2 for storage or shipping purposes. This configuration is convenient for sheet dimensions that are larger than 0.5 m x 0.5 m. The coated antifouling films 200 of the present invention may be produced in the form of a sheet rolled into a coil as demonstrated in FIG. 1 , which allows for easy application of narrower but longer films (e. g., less than 0.5 m wide and up to 200 m long) in the field.

[0061] The coated antifouling films of the present invention demonstrate antifouling efficacy against a range of contaminants including inorganic scale (e.g. calcium carbonate, barium sulfate, magnesium carbonate), fog such as aqueous fog, proteins, fats such as plant oils, lard, tallow and grease, tar, resins, aromatic hydrocarbons, alkanes, bitumens, paraffinic compounds, waxes and / or asphaltene-type compounds, confirmed through performance testing under relevant operational conditions.

[0062] The present invention is thus further drawn to a method of inhibiting fouling of an article component 400 by a contaminant such as inorganic scale (e.g. calcium carbonate, barium sulfate, magnesium carbonate), aqueous fog, proteins, fats, tar, resins, aromatic hydrocarbons, alkanes, bitumens, paraffinic compounds, waxes and / or asphaltene-type compounds. The method comprises:(a) providing a coated antifouling film 200; and(b) adhesively applying the coated antifouling film 200 to at least one surface of the component 400, wherein the coated antifouling film 200 comprises:(1) a flexible polymeric film 202 having a first surface and an opposing second surface, wherein the first surface comprises an activated surface 204 formed by:(1) modifying the first surface of the flexible polymeric film 202 via flame, corona discharge, argon plasma discharge, or chemical etching to form reactive functional groups on the first surface of the flexible polymeric film 202, or(ii) applying an activated layer comprising metal to the first surface of the flexible polymeric film 202 to form reactive functional groups on the first surface of the flexible polymeric film 202;(2) an initiator layer 206 comprising a polymerization initiator chemically bonded to the activated surface 204 via reaction with the reactive functional groups on the activated surface 204; and(3) a hydrophilic polymeric coating layer 208 prepared by a radical polymerization process from a monomer composition comprising at least one free radical polymerizable monomer having at least one hydrophilic functional group, wherein the hydrophilic polymeric coating layer is chemically bonded to and propagated from the polymerization initiator.

[0063] The component 400 may be an industrial equipment component; for example, a conduit such as a culvert or pipe shown in figure 7B; an oil or gas operations equipment component as shown in figure 7C; a medical device component, including implantable devices such as scopes, glucose sensors, pacemakers, and catheters; an optical device component such as an optical sensor, viewport, microscope component, window for viewing measurement equipment, lens, windshield, display screen, or goggles; a fluidic system component; a heat exchanger component; an oil remediation equipment component; a marine component such as an underwater conduit or other structure such as an offshore oil rig support, a turbine blade or hull of a boat or ship as shown in figure 7A; or a wind blade.

[0064] The oil or gas operation equipment component may comprise any production, transport, or other operation component of the oil and gas industry; for example, a flow conduit (i. e., fluidic channels such as a pipe, pipeline or microchannel), a coalescer plate, a pump (e. g., rod pump), a closed loop CO2 geothermal well, a storage well, a CO2 injector well for Enhanced Oil Recovery (EOR) or Coal Bed Methane (CBM) extraction operations, a tank (such as transportable ISO or other storage tank, a holding tank), a heat exchanger, a filter component, drilling equipment such as pipes and bits, an offshore oil or wind turbine platform including structural supports, a blowout preventer, casing, a flow control or measurement device (Coriolis meter, electromagnet flow meter, valve or eductor), a level sensor, oil spill remediation equipment such as skimmers and booms, containment barriers, separators, response robots, and bioremediation equipment, undersea “Christmas trees”, or oil processing equipment.

[0065] Non-limiting examples of suitable heat exchangers include those used on offshore oil platforms, in refinery operations, in natural gas processing , and petrochemical plants. For example:1. Shell and Tube Heat Exchangers: These exchangers may be coated on the internal tubes and / or shell surfaces. Benefits: Reduces fouling from hydrocarbons, prevents corrosion from aggressive chemicals, and improves heat transfer efficiency.2. Plate Heat Exchangers: Coatings can be applied to the plates, which are often made from metals prone to fouling and corrosion. Benefits: Enhances resistance to chemical attack, reduces scaling, and prevents the build-up of residue, which helps maintain performance and simplifies maintenance.3. Air Cooled Heat Exchangers: Finned surfaces may be coated to prevent fouling from airborne particulates and environmental contaminants. Benefits: Improves heat transfer efficiency by keeping fins clean and functional, extends the service life of the exchanger.4. Double Pipe Heat Exchangers: Coating the internal and external surfaces of the pipes prevents fouling and corrosion. Benefits: Reduces maintenance frequency and costs by preventing scale and sediment build-up inside the pipes.5. Spiral Heat Exchangers: Coating the spiral plates or the internal surfaces protects against fouling and corrosion. Benefits: Ensures a longer operational life and consistent performance by minimizing deposit formation and corrosion.

[0066] Non-limiting examples of oil spill remediation equipment include:1 . Booms and Barriers: Floating booms and barriers coated with the polymeric material may be deployed to contain and prevent the spread of oil spills. Benefits: The hydrophilic and anti-fouling properties of the coating prevent the adherence of oil and debris, maintaining the effectiveness of the booms over extended periods.2. Skimmers: Mechanical skimmers equipped with coated surfaces may be used to remove oil from the water surface. Benefits: The low contact angle of the coating reduces the resistance of oil flow, enhancing the skimmer’s efficiency in collecting oil. The anti-fouling properties also reduce maintenance needs.3. Oil-Water Separators: Coated components within oil-water separators may help in the efficient separation of oil from water. Benefits: The hydrophilic coating facilitates the flow and separation process by reducing clogging and fouling, ensuring continuous operation and reducing downtime.

[0067] The coated antifouling film 200 may be any of those disclosed above, adhesively applied to at least one surface of the article component 400.

[0068] Whereas particular embodiments of this invention have been described above for purposes of illustration, it will be evident to those skilled in the art that numerous variations of the details of the present invention may be made without departing from the scope of the invention as defined in the appended claims.

Claims

WHAT IS CLAIMED IS:1 . A coated antifouling film comprising:(a) a flexible polymeric film having a first surface and an opposing second surface, wherein the first surface comprises an activated surface formed by:(i) modifying the first surface of the flexible polymeric film via flame, corona discharge, argon plasma discharge, or chemical etching to form reactive functional groups on the first surface of the flexible polymeric film, or(ii) applying an activated layer comprising metal to the first surface of the flexible polymeric film to form reactive functional groups on the first surface of the flexible polymeric film;(b) an initiator layer comprising a polymerization initiator chemically bonded to the activated surface via reaction with the reactive functional groups on the activated surface; and(c) a hydrophilic polymeric coating layer prepared by a radical polymerization process from a monomer composition comprising at least one free radical polymerizable monomer having at least one hydrophilic functional group, wherein the polymeric coating layer is chemically bonded to and propagated from the polymerization initiator.

2. The coated antifouling film of claim 1 , wherein the flexible polymeric film comprises a polymer selected from at least one of polyethylene terephthalate (PET), a polyamide, a polyamide-polyether block copolymer, a poly(meth)acrylate, a polyester, a polyolefin, a polyisoprene, a polyurethane, a polyester-polyurethane copolymer, a polyimide, a cycloolefin polymer, a polyether ketone, a polysulfone, a polycarbonate and a polysiloxane.

3. The coated antifouling film of claim 1 , wherein the coated antifouling film is in the form of a planar sheet or a sheet rolled into a coil.

4. The coated antifouling film of claim 1 , wherein the activated surface is formed by (ii) applying the activated layer comprising metal to the first surface of the flexible polymeric film, and wherein the activated layer comprises one or more of Ti, Cr, Al, Ta, Nb,Ni, silver oxide, gold oxide, palladium oxide, platinum oxide, rhodium oxide, iridium oxide, tantalum oxide, aluminum oxide, copper oxide, titanium oxide, iron oxide, zirconium oxide, silicon oxide and chromium oxide.

5. The coated antifouling film of claim 1 , wherein the polymerization initiator comprises a halogen selected from chlorine, bromine and iodine.

6. The coated antifouling film of claim 1 , wherein the polymerization initiator is a controlled radical polymerization initiator comprising a-halooisobutyryl halide, benzyl halide, 2-halopropionitrile, azobisbutyronitrile, 1 ,T-azobis(cyclohexanecarbonitrile), 4,4- azobis (4-cyanopentanoic acid), or potassium persulfate (K2S2O8).

7. The coated antifouling film of claim 1 , wherein the hydrophilic polymeric coating layer (c) is formed from an aqueous monomer composition comprising at least one of a (meth)acrylamide halide salt, 2-aminoethylmethacrylamide hydrochloride halide salt, N,N’-(3-(dimethylamino)propyl) methacrylamide, N,N-(3-dimethylamino)propyl)- methacryloylaminobutyl sulfonate, N,N-(3-dimethylamino)propyl)-methacryloylaminopropyl sulfonate, 2-acrylamidopropane-2-methyl-1 -propane sulfonic acid salt, [3- (methacryloylamino)propyl]trimethylammonium chloride, [3-(acryloylamino)propyl]trimethylammonium chloride, N,N’-dimethyl(meth)acrylamide and salts thereof, 3-[(3-(meth)acrylamidopropyl)dimethylammonio]propanoate, a styrene functional monomer, acrylonitrile, (meth)acrylamide functional monomer, 4-vinylpyridine, sodium 4-vinylbenzenesulfonate, and a monomer that is quaternized with a halide or has functional groups that are capable of being quaternized with a halide after polymerization.

8. The coated antifouling film of claim 1 , wherein the hydrophilic polymeric coating layer (c) comprises a homopolymer of a (meth)acrylamide halide salt, 2- aminoethylmethacrylamide hydrochloride halide salt, N,N’-(3-(dimethylamino)propyl) methacrylamide, N,N-(3-dimethylamino)propyl)-methacryloylaminobutyl sulfonate, N,N-(3- dimethylamino)propyl)-methacryloylaminopropyl sulfonate, 2-acrylamidopropane-2- methyl-1 -propane sulfonic acid salt, [3-(methacryloylamino)propyl]trimethylammoniumchloride, [3-(acryloylamino)propyl]trimethylammonium chloride, N,N’- dimethyl(meth)acrylamide or salts thereof, or 3-[(3- (meth)acrylamidopropyl)dimethylammonio]propanoate.

9. The coated antifouling film of claim 1 , wherein the hydrophilic polymeric coating layer (c) comprises a block copolymer.

10. The coated antifouling film of claim 1 , further comprising (d) an adhesive layer applied to the opposing second surface of the flexible polymeric film, wherein when the adhesive layer (d) comprises a pressure sensitive adhesive, the coated antifouling film optionally further comprises (e) a removable backing layer applied to the adhesive layer (d).1 1 . The coated antifouling film of claim 1 , wherein the coated antifouling film demonstrates antifouling by a contaminant comprising inorganic scale, aqueous fog, proteins, fats, tar, resins, aromatic hydrocarbons, alkanes, bitumens, waxes and / or asphaltene-type compounds.

12. A method of preparing an antifouling coated film comprising:(a) forming an activated surface on a first surface of a flexible polymeric film having the first surface and an opposing second surface, wherein the activated surface is formed by:(i) modifying the first surface of the flexible polymeric film via flame, corona discharge, argon plasma discharge, or chemical etching to form reactive functional groups on the first surface of the flexible polymeric film, or(ii) applying an activated layer comprising metal to the first surface of the flexible polymeric film to form reactive functional groups on the first surface of the flexible polymeric film;(b) chemically bonding a polymerization initiator to the activated surface via reaction with the reactive functional groups on the activated surface to form an initiator layer;(c) contacting the initiator layer with an aqueous monomer composition comprising at least one free radical polymerizable monomer having at least one hydrophilic functional group;(d) allowing the monomers in the aqueous monomer composition to polymerize via a radical polymerization process to form a hydrophilic polymeric coating layer, wherein the hydrophilic polymeric coating layer is chemically bonded to and propagated from the polymerization initiator; and optionally(e) curing the hydrophilic polymeric coating layer by reaction of reactive functional groups in the hydrophilic polymeric coating layer.

13. The method of claim 12, wherein the activated surface is formed by (ii) applying the activated layer comprising metal to the first surface of the flexible polymeric film, and wherein the activated layer is applied via chemical vapor deposition, physical vapor deposition, electron beam evaporation, or electroless deposition from solution.

14. The method of claim 12, wherein after step (a), the method further comprises applying a removable protective layer to the activated surface, and subsequently removing the protective layer prior to step (b).

15. The method of claim 12, wherein the aqueous monomer composition is contacted with the initiator layer via spraying, brushing, or dipping.

16. The method of claim 12, further comprising (f) applying an adhesive layer to the opposing second surface of the flexible polymeric film, wherein when the adhesive layer comprises a pressure sensitive adhesive, the method optionally further comprises (g) applying a removable backing layer to the adhesive layer.

17. A method of inhibiting fouling of an article component by a contaminant, comprising:(a) providing a coated antifouling film; and(b) adhesively applying the coated antifouling film to at least one surface of the article component, wherein the coated antifouling film comprises:(1 ) a flexible polymeric film having a first surface and an opposing second surface, wherein the first surface comprises an activated surface formed by:(1) modifying the first surface of the flexible polymeric film via flame, corona discharge, argon plasma discharge, or chemical etching to form reactive functional groups on the first surface of the flexible polymeric film, or(ii) applying an activated layer comprising metal to the first surface of the flexible polymeric film to form reactive functional groups on the first surface of the flexible polymeric film;(2) an initiator layer comprising a polymerization initiator chemically bonded to the activated surface via reaction with the reactive functional groups on the activated surface; and(3) a hydrophilic polymeric coating layer prepared by a radical polymerization process from a monomer composition comprising at least one free radical polymerizable monomer having at least one hydrophilic functional group, wherein the hydrophilic polymeric coating layer is chemically bonded to and propagated from the polymerization initiator.

18. The method of claim 17, wherein the article component comprises a conduit, an oil or gas operation component, a medical device component, an optical device component, a fluidic system component, a heat exchanger component; an oil remediation equipment component; a marine component; or a wind blade.

19. The method of claim 17, wherein the coated antifouling film is provided in the form of a planar sheet or a sheet rolled into a coil prior to application of the coated antifouling film to the surface of the article component.

20. The method of claim 17, wherein the contaminant comprises inorganic scale, aqueous fog, proteins, fats, tar, resins, aromatic hydrocarbons, alkanes, bitumens, waxes and / or asphaltene-type compounds.

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