Polymer functionalized substrates, methods of making same, and uses thereof

Abstract

Polymer functionalized substrates, methods of making polymer functionalized substrate, and uses of polymer functionalized substrates. A polymer functionalized substrate comprises a plurality of polymer groups (which may be referred to as polymer brushes), disposed on a surface of a substrate. In various examples, a polymer functionalized substrate is made by irradiating a substrate with monomer(s), photocatalyst(s), and chain transfer agent(s) disposed thereon, where the polymer groups are formed. In various examples, a method comprises a surface-initiated hydrogen atom transfer (HAT)-reversible addition-fragmentation chain transfer (RAFT) polymerization. In various examples, a polymer functionalized substrate is configured or suitable for use as lubricant, a viscosity modifier, or a filtration membrane. In various examples, an article of manufacture, such as, for example, a medical device, comprises a polymer functionalized substrate. In various examples, an article of manufacture exhibits a desirable property, such as, for example, antimicrobial or antifouling activity, wettability, hydrophobicity, or scratch / abrasion resistance.

Description

POLYMER FUNCTIONALIZED SUBSTRATES, METHODS OF MAKING SAME, AND USES THEREOFCROSS-REFERENCE TO RELATED APPLICATIONS

[0001] This application claims the benefit of U.S. Provisional Patent Application No. 63 / 620,122, filed January 11, 2024; the contents of the above-identified application are hereby fully incorporated herein by reference in their entirety.STATEMENT REGARDING FEDERALLY SPONSORED RESEARCH

[0002] This invention was made with government support under grant no. CHE- 2203758 awarded by the National Science Foundation. The government has certain rights in the invention.BACKGROUND

[0003] Polyethylene (PE) is ubiquitous in our society, with over 100 million tons produced annually. The widespread use of PE is enabled by its superior bulk properties and low cost; PE is strong, tough, light weight, and chemically resistant. Despite these advantages, poor surface properties such as low adhesivity and wettability limit its use in applications such as battery membranes, packaging, and automotive materials, all of which require interfacing with other plastics, metals, and solvents. Furthermore, the surface of PE contains only unactivated C — C and C — H bonds, making it challenging to modify. This difficulty in functionalization hampers the synthesis of PEs with high-performance surfaces such as anti-fouling biomedical implants, antibacterial high-touch surfaces, or chemically selective filtration membranes. A method to imbue PE surfaces with improved or novel properties would facilitate the development of next generation polymeric materials.

[0004] Previous attempts to modify the chemistry of PE have relied on either oxidation of the PE surface or impregnating PE films with a photosensitizer. In the first case, oxidative functionalization to yield carboxylic acids or free radicals on the surface is carried out under harsh conditions using strong acids or plasma. This approach requires specialized equipment and often leads to degradation of PE chains at the surface. Furthermore, the resulting small molecule functionality tends to migrate into the bulk of the polymer to lower surface energy, leading to a short lifetime of functionalization. In the second case, a PE film is first soaked in benzophenone photosensitizer, dried, and finally polymer is grafted from the sensitized surface under UV irradiation. While this method is often used to prepare biomedicalmaterials, its multi-step nature and frequently reported low grafting densities make it difficult to efficiently functionalize PE surfaces.SUMMARY OF THE DISCLOSURE

[0005] The present disclosure provides, inter alia, polymer functionalized substrates. The present disclosure also provides methods of making polymer functionalized substrates and uses thereof.

[0006] In an aspect, the present disclosure provides polymer functionalized substrates. In various examples, a polymer functionalized substate or the like, comprises a plurality of polymer groups (which may be referred to as polymer brushes or the like) disposed on a substrate. In various examples, a polymer functionalized substate or the like is formed by a method of the present disclosure. In various examples, a polymer functionalized substrate comprises a substrate comprising a polymer (such as, for example, a polyolefin, a polystyrenes, a polyether, a polyamide, a aliphatic polyester, a structural analog thereof (e.g. a crosslinked analog thereof), copolymer thereof, or the like); and a plurality of polymer groups (which may be referred to as polymer brushes or the like). The polymer groups are disposed on (e.g., independently at each occurrence covalently bound or the like to) at least a portion of, substantially all, or all of a surface (such as, for example, an exterior surface of a substrate or the like) or all surfaces (such as, for example, exterior surfaces of the polymer (or polymer layer) of the substrate or the like). In various examples, each of the plurality of polymer groups are grafted from the substrate and / or each of the plurality of polymer groups are independently at each occurrence covalently bound via a carbon-carbon covalent bond (such as, for example, a carbon-carbon single bond or the like) or the like to a surface of a substrate and / or each carbon-carbon bond of the polymer groups is formed by a polymerization reaction, such as, for example, a radical polymerization (e.g., a surface- initiated hydrogen atom transfer (HAT)-reversible addition-fragmentation chain transfer (RAFT) polymerization or the like) or the like. In various examples, the polymer groups are chosen from polyacrylate groups, polymethacrylate groups, polyacrylamide groups, polymethacrylamide groups, polyvinyl acetate groups, polymaleic anhydride groups, polymaleimide groups, polyolefin groups, polymer groups comprising one or more PEG group(s), zwitterionic polymer groups (e.g., polymer groups comprising one or more zwitterioinic group(s)), structural analogs thereof, and the like, copolymers thereof, and any combination thereof and / or the polymer groups independently have a molecular weight of about 100 g / mol to about 100,000 g / mol, including all 0.1 g / mol values and rangestherebetween, and / or independently comprise about 1 repeat unit to about 1000 repeat units, including all integer repeat unit values and ranges therebetween, and / or a degree of polymerization of at least about 10 or more, at least about 15 or more, at least about 20 or more, at least 25 or more, or at least 50 or more and / or the polymer groups independently at each occurrence comprise (or the polymer groups form a polymer group layer comprising) a dimension substantially normal or normal to a plane defining a surface of the substrate (such as, for example, a thickness or the like) of about 10 nm to about 1000 nm, including all 0.1 nm values and ranges therebetween, and / or a polymer functionalized substrate comprises about 0.05 chains / nm2to about 6 chains / nm2, including all 0.01 chains / nm2values and ranges therebetween.

[0007] In an aspect, the present disclosure provides methods of making polymer functionalized substrates. In various examples, a method of making a polymer functionalized substrate (e.g., a polymer functionalized substrate of the present disclosure) comprises irradiating (or contacting or subjecting) at least a portion, substantially all, or all of a surface or the surfaces of a substrate comprising one or more polymer(s) with one or more monomer(s) (such as, for example, acrylates, methacrylates, acrylamides, methacrylamides, vinyl acetates, maleic anhydrides, maleimides, olefins, zwitterionic monomers, structural analogs thereof, and the like, and any combination thereof), one or more photocatalyst(s) (such as, for example, aromatic ketones (such as, for example, benzophenones, which may be structural benzophenones, and the like), thioxanthones, xanthene dyes, polyoxometalates, uranyl salts, metal-oxo porphyrins, tris(amino)cyclopropenium radical dications, structural analogs thereof, and the like, and any combination thereof), one or more chain transfer agent(s) (such as, for example, disulfide derivatives of trithiocarbonates, dithioates, diothiocarbamates, xanthates, a Z group in a RAFT polymerization, and the like, and any combination thereof), and, optionally, one or more solvent(s) (e.g., one or more of which is a hydridic solvent or the like) disposed on the at least a portion, substantially all, or all the surfaces of the substrate with (or to) electromagnetic radiation. In various examples, the substrate comprises one or more (e.g., a plurality of) carbon-hydrogen group(s) (e.g., comprises carbon-hydrogen bond(s)), which may be neutral electron density carbon-hydrogen bonds (e.g., neutral electron density carbon-hydrogen group(s)), hydridic carbon-hydrogen bonds (e.g., hydridic carbon-hydrogen groups), or the like, or any combination thereof, disposed on a surface of the substrate. In various examples, the method comprises (or is) a radical polymerization or radical polymerizations, or the like, or any combination thereof, any or all of which may be a surface-initiated polymerization (such as, for example, asurface-initiated hydrogen atom transfer (HAT)-reversible addition-fragmentation chain transfer (RAFT) polymerization or the like) or the like. In various examples, the polymer groups of the polymer functionalized substrate or the like are grafted from a surface of the substrate.

[0008] In an aspect, the present disclosure provides uses of polymer functionalized substrates of the present disclosure. A polymer functionalized substrate is suitable and / or configured for use as a lubricant, a viscosity modifier, or the like). In various examples, a polymer functionalized substrate is suitable and / or configured for use in a medical or biomedical device, in marine applications, as a coating for high touch surfaces, in battery applications, upcycling post-consumer plastics, food packaging, to provide a paintable surface, as a membrane for a chemically selective filtration, to provide scratch resistant coatings, or the like. In various examples, an article of manufacture comprises one or more polymer functionalized substrate(s) (e.g., a polymer functionalized substrate(s) or the like) of the present disclosure. In various examples, the article of manufacture is a biomedical device (such as, for example, an artificial joint or the like), a marine article (such as, for example, a boat / ship hull, a component, or the like), an automotive article (such as, for example, an automotive part (e.g., a door, upholstery, a fender, a bumper, a hood, or the like), a consumable (e.g., an eating device (e.g., a fork, a spoon, a knife, etc.) or the like), a container, a securing device (such as, for example, a tie or the like), a tray, a membrane (e.g., a polyolefin membrane or the like) (such as, for example, an electrochemical (e.g., battery or the like) membrane (such as, for example, a polyolefin membrane or the like), a filtration membrane, or the like), or the like. In various examples, the article of manufacture exhibits one or more desirable propert(ies), such as, for example, desirable friction (such as, for example, low friction, antifouling activity, antimicrobial activity, antiviral activity, desirable wettability, hydrophobicity, chemoselectivity; stimuli responsive activity, scratch / abrasion resistance, or the like, or any combination thereof.

[0009] In various examples, methods of the present disclosure provide polymer functionalized substrates with a desirable functionalization density (e.g., a functionalization density for polymerizing from polyethylene surfaces at about 0.6 chains / nm2or greater). In various examples, the methods provide one step functionalization — grafting polymer directly from the C — H bonds of a polymer of a substrate. No prior modification of the polymer nor synthesis of a designer polyolefin is required. This feature of the methods obviates the need for expensive reagents or multistep syntheses, and enables the use of commercial polymer substrates for which there already exists industry scale production.BRIEF DESCRIPTION OF THE FIGURES

[0010] For a fuller understanding of the nature and objects of the disclosure, reference should be made to the following detailed description taken in conjunction with the accompanying figures.

[0011] FIG. 1 shows surface-initiated hydrogen atom transfer reversible additionfragmentation chain transfer (HAT -RAFT) polymerization that leverages direct initiation from the surface of PE to allow for facile synthesis of high-density brushes.

[0012] FIG. 2 shows a. Standard reaction conditions for SI HAT -RAFT from PE. b. IR spectra of unfunctionalized HDPE and HDPE-g-PtBuA. c. Static water contact angle for HDPE and HDPE-g-PNaA.

[0013] FIG. 3 shows a. AFM measurement of LLDPE-g-PtBuA brush thickness. Brush thickness is assessed by comparing the depth of a scratch (pictured here by optical microscopy) in an LLDPE film before and after grafting, b. AFM swelling study of LLDPE- g-PNaA in pH 9 buffer solution shows the wet film swells 63% relative to the dry film. The dashed lines denote the average film height over the scan distance.

[0014] FIG. 4 shows an example of monomer scope of SI HAT -RAFT, where a is the standard reaction condition: photocatalyst 1 (1 equiv.), CTA 2 (1 equiv.), monomer (200 equiv.), and dioxane (0.04 M in CTA) irradiated with a CFL at room temperature in a nitrogen atmosphere for 16 hours. For the sulfobetaine zwitterion and the PEG derivative, water was used in place of dioxane. For the sulfobetaine zwitterion, the reaction was run at half the overall concentration due to poor monomer solubility.

[0015] FIG. 5. Tape test for acrylic paint adhesion of an HDPE (left) and an HDPE-g- [PMMA-co-PnBuA] (right).

[0016] FIG. 6 shows a depiction of the general surface-initiated HAT -RAFT strategy.

[0017] FIG. 7 shows a general reaction set up for a surface-initiated HAT -RAFT.

[0018] FIG. 8 shows an infrared (IR) spectrum of an HDPE before (gray trace) and after (red trace) thermal RAFT conditions.

[0019] FIG. 9 shows an IR spectrum of a glass before (gray trace) and after (red trace) reaction.

[0020] FIG. 10 shows Mylar® substrate before (gray) and after (red) general HATRAFT conditions.

[0021] FIG. 11 shows an x-ray photoelectron (XPS) spectrum (survey scan) of an LLDPE- -P'BA.

[0022] FIG. 12 shows an XPS spectrum (carbon high resolution scan) of LLDPE-g- P^BA.

[0023] FIG. 13 shows an XPS spectrum (oxygen high resolution scan) of LLDPE-g- P^BA.

[0024] FIG. 14 shows a. AFM profile of boundary between scratched and unscratched area of LLDPE-g-P'BuA film (300 nm scratch depth, 260 nm brush thickness), b. AFM image of LLDPE-g-P'BuA film.

[0025] FIG. 15 shows a. Profilometer image of scratch with razor blade on LLDPE-g- P'BuA film. b. Height profile of scratch on right. Scratch depth is 1.835 pm. Brush height is 236 nm.

[0026] FIG. 16 shows water contact angle of HDPE-g-PNaA films irradiated for varying amounts of time.

[0027] FIG. 17 shows lap shear comparison of A1-LDPE-A1 and Al-(LDPE-g-PMMA)- A1 lap joints. A1-LDPE-A1 samples underwent adhesive failure before shear force was applied. Al-(LDPE-g-PMMA)-Al underwent adhesive failure with a shear strength of 1.1 ± 0.2 MPa.

[0028] FIG. 18 shows an IR spectrum of a polymer functionalized substrate formed using a tBuMA monomer and a thioxanthone photocatalyst.

[0029] FIG. 19 shows an IR spectrum demonstrating lack of observable polymerization in absence of the disulfide.

[0030] FIG. 20 shows an IR spectrum demonstrating lack of observable polymerization in absence of the disulfide with 5x photocatalyst loading.

[0031] FIG. 21 shows an IR spectrum demonstrating lack of observable polymerization using ferrocenium tetrafluoroborate (Fc(BF4) as a chemical oxidant

[0032] FIG. 22 shows an IR spectrum demonstrating lack of observable polymerization initiation using a Mylar® (biaxially oriented polyethylene terephthalate) substrate.

[0033] FIG. 23 shows an IR spectrum demonstrating lack of observable polymerization in initiation using a glass microscope slide (silicate glass).

[0034] FIG. 24 shows an XPS spectrum demonstrating lack of observable polymerization in initiation using octacadecane immobilized on a silicon substrate.

[0035] FIG. 25 shows an IR spectrum demonstrating functionalization of an isotactic polypropylene (iPP) membrane.

[0036] FIG. 26 shows an IR spectrum demonstrating functionalization of an isotactic polypropylene substrate.

[0037] FIG. 27 shows an IR spectrum demonstrating functionalization using a zwitterionic monomer.

[0038] FIG. 28 shows an IR spectrum demonstrating functionalization using a trimethoxypropyl silyl acrylate (TMPSA) monomer.

[0039] FIG. 29 shows an IR spectrum demonstrating functionalization using a tri decafluorooctyl acrylate (TDFOA) monomer.

[0040] FIG. 30 shows an IR spectrum demonstrating functionalization of a polyethylene / isotactic polypropylene copolymer substrate.

[0041] FIG. 31 shows an IR spectrum demonstrating functionalization of an LDPE plastic wrap substrate.

[0042] FIG. 32 shows an IR spectrum demonstrating functionalization of an HDPE plastic container.

[0043] FIG. 33 shows an IR spectrum demonstrating functionalization of a polyamide (Nylon) substrate.

[0044] FIG. 34 shows an IR spectrum demonstrating functionalization of a polyether (iPPO) substrate.DETAILED DESCRIPTION OF THE DISCLOSURE

[0045] Although subject matter of the present disclosure is described in terms of certain examples, other examples, including examples that do not provide all of the benefits and features set forth herein, are also within the scope of this disclosure. For example, various structural, logical, and process step changes may be made without departing from the scope of the disclosure.

[0046] As used herein, unless otherwise indicated, “about”, “substantially”, or “the like”, when used in connection with a measurable variable (such as, for example, a parameter, an amount, a temporal duration, or the like) or a list of alternatives, is meant to encompass variations of and from the specified value including, but not limited to, those within experimental error (which can be determined by, e.g., a given data set, an art accepted standard, etc. and / or with, e.g., a given confidence interval (e.g., 90%, 95%, or more confidence interval from the mean), such as, for example, variations of + / - 10% or less, + / -5% or less, + / -1% or less, and + / -0.1% or less of and from the specified value), insofar such variations in a variable and / or variations in the alternatives are appropriate to perform in theinstant disclosure. As used herein, the term “about” may mean that the amount or value in question is the exact value or a value that provides equivalent results or effects as recited in the claims or taught herein. That is, it is understood that amounts, sizes, compositions, parameters, and other quantities and characteristics are not and need not be exact, but may be approximate and / or larger or smaller, as desired, reflecting tolerances, conversion factors, rounding off, measurement error, or the like, or other factors known to those of skill in the art such that equivalent results or effects are obtained. In general, an amount, size, composition, parameter, or other quantity or characteristic, or alternative is “about” or “the like,” whether or not expressly stated to be such. It is understood that where “about,” is used before a quantitative value, the parameter also includes the specific quantitative value itself, unless specifically stated otherwise.

[0047] Ranges of values are disclosed herein. The ranges set out a lower limit value and an upper limit value. Unless otherwise stated, the ranges include the lower limit value, the upper limit value, and all values between the lower limit value and the upper limit value, including, but not limited to, all values to the magnitude of the smallest value (either the lower limit value or the upper limit value) of a range. It is to be understood that such a range format is used for convenience and brevity, and thus, should be interpreted in a flexible manner to include not only the numerical values explicitly recited as the limits of the range, but also to include all the individual numerical values or sub-ranges encompassed within that range as if each numerical value and sub-range is explicitly recited. To illustrate, a numerical range of “0.1% to 5%” should be interpreted to include not only the explicitly recited values of 0.1% to 5%, but also, unless otherwise stated, include individual values (e.g., 1%, 2%, 3%, and 4%) and the sub-ranges (e.g., 0.5% to 1.1%; 0.5% to 2.4%; 0.5% to 3.2%, and 0.5% to 4.4%, and other possible sub-ranges) within the indicated range. It is also understood (as presented above) that there are a number of values disclosed herein, and that each value is also herein disclosed as “about” that particular value in addition to the value itself. For example, if the value “10” is disclosed, then “about 10” is also disclosed. Ranges can be expressed herein as from “about” one particular value, and / or to “about” another particular value. Similarly, when values are expressed as approximations, by use of the antecedent “about,” it will be understood that the particular value forms a further disclosure. For example, if the value “about 10” is disclosed, then “10” is also disclosed.

[0048] As used herein, unless otherwise stated, the term “group” refers to a chemical entity that is monovalent (i.e., has one terminus that can be (is) covalently bonded to other chemical species), divalent, or polyvalent (i.e., has two or more termini that can be (are)covalently bonded to other chemical species). The term “group” also includes radicals (e.g., monovalent radicals and multivalent radicals, such as, for example, divalent radicals, trivalent radicals, and the like). Illustrative examples of groups include:the like.

[0049] As used herein, unless otherwise indicated, the term “alkyl group” refers to branched or unbranched hydrocarbon groups that include only single bonds between carbon atoms (not including substituent(s), if any). In various examples, an alkyl group is a Ci to C20 alkyl group (e.g., Ci, C2, C3, C4, C5, C6, C7, Cs, C9, C10, Cn, C12, C13, C14, C15, Ci6, C17, Ci8, C19, or C20), including all integer numbers of carbons and ranges of numbers of carbons therebetween. In various examples, an alkyl group is a saturated group. In various examples, an alkyl group is a cyclic alkyl group, which may be a heterocyclic alkyl group, e.g., a monocyclic alkyl group or a polycyclic alkyl group or the like, or the like, or the like. Examples of alkyl groups include, but are not limited to, methyl groups, ethyl groups, propyl groups, butyl groups, isopropyl groups, tert-butyl groups, cyclohexyl groups, adamantyl groups, benzyl groups and the like. In various examples, an alkyl group is unsubstituted or substituted with one or more substituent(s). Examples of substituents include, but are not limited to, substituents, such as, for example, halide groups (-F, -Cl, -Br, and -I), aliphatic groups (e.g., alkyl groups, alkenyl groups, alkynyl groups, and the like), halogenated aliphatic groups (e.g., trifluoromethyl group and the like), aryl groups, halogenated aryl groups, hydroxyl group, amine groups, nitro group, cyano groups, isocyano groups, azide group, silane groups (e.g., alkyl silane groups, aryl silane groups, alkyl / aryl silane groups, or the like), alkoxide groups, alcohol groups, ether groups, ketone groups, carboxylate groups, carboxylic acid groups, ester groups, amide groups, thioether groups, thioester groups, and the like, and any combination thereof.

[0050] As used herein, unless otherwise indicated, the term “aryl group” refers to C5 to C30 fully aromatic or partially aromatic carbocyclic groups. In various examples, an aryl group is a C5 to C30 aromatic or partially aromatic carbocyclic group (e.g., C5, Ce, C7, C8, C9, C10, Cn, C12, C13, C14, C15, C16, C17, C18, C19, C20, C21, C22, C23, C24, C25, C26, C27, C28, C29, and C30), including all integer numbers of carbons and ranges of numbers of carbons therebetween. In various examples, an aryl group comprises (or is) one or more polyaryl group(s) (such as, for example, fused ring group(s), biaryl group(s), or the like, or any combination thereof) or the like, or any combination thereof. In various examples, an arylgroup is unsubstituted or substituted with one or more substituent(s). Examples of substituents include, but are not limited to, substituents such as, for example, halide groups (- F, -Cl, -Br, and -I), aliphatic groups (e.g., alkyl groups, alkenyl groups, alkynyl groups, and the like), halogenated aliphatic groups (e.g., trifluoromethyl group and the like), aryl groups, halogenated aryl groups, hydroxyl group, amine groups, nitro group, cyano groups, isocyano groups, azide group, silane groups (e.g., alkyl silane groups, aryl silane groups, alkyl / aryl silane groups, or the like), alkoxide groups, alcohol groups, ether groups, ketone groups, carboxylate groups, carboxylic acid groups, ester groups, amide groups, thioether groups, thioester groups, and the like, and any combination thereof.. In various examples, an aryl groups comprises one or more heteroatom(s) (such as, for example, oxygen(s), nitrogen(s) (e.g., pyridinyl groups and the like), sulfur(s), and the like, and any combination thereof), which may be referred to as heteroaryl groups. Examples of aryl groups include, but are not limited to, phenyl groups, biaryl groups (e.g., biphenyl groups and the like), fused ring groups (e.g., naphthyl groups and the like), hydroxybenzyl groups, tolyl groups, xylyl groups, furanyl groups, pyrrolyl groups, thiophenyl groups, benzofuranyl groups, indolyl groups, imidazolyl groups, benzimidazolyl groups, pyridinyl groups, and the like.

[0051] As used herein, unless otherwise stated, the term “structural analog” refers to any monomer, polymer group, or the like, or any portion thereof (such as, for example, one or more group(s) thereof or the like) or group if one atom or group of atoms, functional group or functional groups, or substructure or substructures is / are replaced with another atom or group of atoms, functional group or functional groups, substructure or substructures, or the like. In various examples, the term “structural analog” refers to any group that is derived from an original monomer, polymer group, or the like or a portion thereof (such as, for example, one or more group(s) thereof or the like) or the like by a chemical reaction, where the monomer, the polymer group, or the like or the portion thereof (such as, for example, one or more group(s) thereof or the like) or the like is modified or partially substituted such that at least one structural feature of the monomer, the polymer group, or the like or the portion thereof (such as, for example, one or more group(s) thereof or the like) or the like is retained.

[0052] The present disclosure describes, inter alia, polymer functionalized substrates and methods of making polymer functionalized substrates. In various examples, the present disclosure also provides uses of polymer functionalized substrates.

[0053] In an aspect, the present disclosure provides polymer functionalized substrates. A polymer functionalized substrate may be referred to as a functionalized substrate. In various examples, a polymer functionalized substrate comprises a plurality of polymer groups (whichmay be referred to as polymer brushes or the like) disposed on a substrate. In various examples, a polymer functionalized substrate is formed by a method of the present disclosure. Non-limiting examples of polymer functionalized substrates are provided herein.

[0054] In various examples, a polymer functionalized substrate comprises (or consists essentially of or consists of) a substrate comprising a polymer; and a plurality of polymer groups (which may be referred to as polymer brushes or the like). The polymer groups are disposed on (e.g., independently at each occurrence covalently bound or the like to) at least a portion of, substantially all, or all of a surface (such as, for example, an exterior surface of a substrate or the like) or all surfaces (such as, for example, exterior surfaces of polymer layer or the like).

[0055] A polymer functionalized substrate can comprise various substrates. A substrate comprises a polymer. In various examples, a substrate is a polymer. In various examples, a substrate (which may comprise a polymer or a non-polymer material) comprises a polymer layer (such as, for example, a polymer layer which may be an exterior polymer layer or the like) or the like. In various examples, a polymer layer is disposed on a least a portion, substantially all, or all of one or more or all surface(s) (which may independently be exterior surfaces) of a substrate. Non-limiting examples of substrates are provided herein. In various examples, a substrate is a substrate disclosed herein.

[0056] A substrate can comprise various polymers. In various examples, a substrate comprises a single polymer or two or more different polymers (e.g., structurally different and / or compositionally different) polymers. In various examples, one or more, substantially all, or all of the polymer(s) is / are crosslinked. Non-limiting examples of polymers include polyolefins, polystyrenes, polyethers, polyamides, aliphatic polyesters, structural analogs thereof (e.g., crosslinked analogs thereof), copolymers thereof, and the like, and any combination thereof. Non-limiting examples of polyolefins include polyethylenes, polypropylenes, structural analogs thereof (e.g., crosslinked analogs thereof), and the like, and copolymers thereof, or any combination thereof. Non-limiting examples of polyethylenes include high-density polyethylene, low-density polyethylene, linear high-density polyethylene, linear low-density polyethylene, and the like, structural analogs thereof (e.g., crosslinked analogs thereof) and copolymers thereof, or any combination thereof. Nonlimiting examples of polyethers include polyethylene glycol, polypropylene oxide), structural analogs thereof (e.g., crosslinked analogs thereof), and the like, and copolymers thereof, or any combination thereof. Non-limiting examples of aliphatic polyesters include C3 or greater (e.g., C3-C15, including all integer number of carbons and ranges therebetween)aliphatic polyesters (such as, for example, poly(caprolactone)s, structural analogs thereof (e.g., crosslinked analogs thereof), and the like), and copolymers thereof, and any combination thereof.

[0057] A substrate can have various sizes and / or shapes. One of ordinary skill in the art would appreciate that the size and / or shape of a substrate is not particularly limited. In various examples, a substrate is of a size and / or shape suitable for use in a method of the present disclosure. In various examples, a substrate is a monolith, a three-dimensional substrate (which may be at least partially or completely hollow), a wafer, a container, a film (which may be a thin film (e.g., a supported thin film or the like)), a sheet, a membrane, a pellet or pellets, a fiber (which may be an at least partially hollow or completely hollow fiber), a powder, or the like

[0058] A polymer functionalized substrate comprises a plurality of polymer groups. The polymer groups of a polymer functionalized substrate may be referred to in the aggregate as a grafted layer or the like. In various examples, substantially all or all of the polymer groups of a polymer functionalized substrate substantially the same (e.g., structurally the same and / or compositionally the same). In various examples, at least a portion or two or more portions of the polymer groups of a polymer functionalized substrate are different (e.g., structurally different and / or compositionally different) a least a portion or two or more or all of the other portions of polymer groups.

[0059] In various examples, each of the plurality of polymer groups are independently at each occurrence covalently bound via a carbon-carbon covalent bond (such as, for example, a carbon-carbon single bond or the like) or the like to a surface of a substrate. In various examples, a first carbon of a carbon-carbon bond (such as, for example, a carbon-carbon single bond or the like) is a carbon atom of the substrate and a second carbon of the carboncarbon bond is a carbon (such as, for example, a terminal carbon or the like) of the polymer group. In various examples, polymer groups are grafted from a substrate.

[0060] In various examples, each carbon-carbon bond of a polymer group is formed by a polymerization reaction. Non-limiting examples of polymerization reactions include radical polymerizations and the like, or any combination thereof, which may be surface initiated polymerizations. In various examples, each carbon-carbon bond is formed by a surface- initiated hydrogen atom transfer (HAT)-reversible addition-fragmentation chain transfer (RAFT) polymerization, or the like, or any combination thereof. In various examples, polymer group does not comprise a polymer group or polymer groups comprising preformedpolymer(s) or polymer group(s) (such as, for example, polymer(s) or polymer group(s) formed prior to formation of the polymer group on the substrate).

[0061] In various examples, a polymer group or at least a portion, substantially all, or all of the polymer groups are formed from a monomer described herein. In various examples, at least a portion of, substantially all, or all of the polymer groups are chosen from polyacrylate groups, polymethacrylate groups, polyacrylamide groups, polymethacrylamide groups, polyvinyl acetate groups, polymaleic anhydride groups, polymaleimide groups, polyolefin groups, polymer groups comprising one or more PEG group(s) (such as, for example,, and the like, where x is 1 to 150, including all integer values and ranges therebetween, and z is Ito 10,000, including all integer values and ranges therebetween , or and the like), zwitterionic polymer groups (such as, for example,, where ZG is a zwitterionic group (such as, forindependently at each occurrence an alkyl group or the like (e.g., a sulfobetaine group or the like)), structural analogs thereof, copolymers thereof, and the like, and any combination thereof.

[0062] In various examples, a structural analog of a polymer group comprises alkyl group substituent(s), or the like, or any combination thereof. In various examples, a structuralanalog of a polymer group is a partially, substantially protonated, or completely protonated group or a partially, substantially deprotonated, or completely deprotonated group.

[0063] In various examples, a polymer group comprises an end group at a terminus of the polymer (a terminus other than the terminus disposed on the substrate). In various examples, the end group is formed as a result of the formation of the polymer group (such as, for example, a polymerization or the like) or the like. Non-limiting examples of end groups include -H, a trithiocarb onate group, and the like, or any combination thereof.

[0064] Polymer group composition can be determined by methods known in the art. In various examples, the composition of the polymer groups (e.g., a grafted layer or the like) or a portion thereof is determined by X-ray photoelectron spectroscopy (XPS) or the like and / or functional groups present in the polymer groups (e.g., a grafted layer or the like) or a portion thereof are determined by infrared (IR) spectroscopy or the like.

[0065] A polymer functionalized substrate can comprise polymer groups of various sizes. In various examples, polymer groups independently have (or substantially all or all polymer groups have) a molecular weight of about 100 g / mol to about 100,000 g / mol, including all 0.1 g / mol values and ranges therebetween. In various examples, the polymer groups independently comprise (or substantially all or all polymer groups comprise about 1 repeat unit to about 1000 repeat units, including all integer repeat unit values and ranges therebetween. In various examples, a majority, substantially all, or all of the polymer groups have a degree of polymerization of at least about 10 or more, at least about 15 or more, at least about 20 or more, at least 25 or more, or at least 50 or more. The polymer group size (e.g., polymer group length or the like) can be determined by methods known in the art. In various examples, polymer group size (e.g., polymer group chain length or the like) is determined by profilometry, ellipsometry, atomic force microscopy (AFM), transmission electron microscopy (TEM), or the like. In various examples, polymer group size is determined directly by single molecule force spectroscopy or the like. In various examples, the polymer groups of a polymer functionalized substrate independently at each occurrence comprise (or the polymer groups form a polymer group layer comprising) a dimension substantially normal or normal to a plane defining a surface of the substrate (such as, for example, a thickness or the like) of about 10 nm (nm = nanometer(s)) to about 1000 nm, including all 0.1 nm values and ranges therebetween (e.g., about 50 nm to about 500 nm).

[0066] A polymer functionalized substrate can comprise various polymer group densities. In various examples, a polymer functionalized substrate comprises about 0.05 chains / nm2to about 6 chains / nm2, including all 0.01 chains / nm2values and rangestherebetween (e.g., greater than about 0.2 chains / nm2to about 2 chains / nm2, 0.3 chains / nm2to about 2 chains / nm2, 0.5 chains / nm2to about 2 chains / nm2, greater than about 0.2 chains / nm2to about 4 chains / nm2, 0.3 chains / nm2to about 4 chains / nm2, 0.5 chains / nm2to about 4 chains / nm2, greater than about 0.2 chains / nm2to about 6 chains / nm2, 0.3 chains / nm2to about 6 chains / nm2, 0.5 chains / nm2to about 6 chains / nm2, about 0.5 chains / nm2, about 0.75 chains / nm2). The chain density (e.g., number of chains per square nanometer or the like) can be determined by methods known in the art. In various examples, chain density (e.g., number of chains per square nanometer or the like) is determined by microscopy (such as, for example, atomic force microscopy (AFM), profilometry (such as, for example, optical profilometry, stylus profilometry, or the like), ellipsometry, transmission electron microscopy (TEM), or the like) or the like). In various examples, chain density is calculated from the height of the grafted polymer (measured by AFM, profilometry, TEM, or the like) and an estimate of molecular weight. In various examples, chain density is determined indirectly by swelling studies or the like.

[0067] The polymer groups of a polymer functionalized substrate may be continuous (e.g., form a continuous coating) or a pattern (e.g., form a patterned coating) on at least a portion, substantially, or all of one or more or all surface(s) of a substrate. In various examples, at least a portion, substantially all, or all the polymer groups form a predetermined pattern on at least a portion, substantially all, or all of a surface (or all the surfaces) of the substrate.

[0068] In various examples, a polymer functionalized substrate is configured or suitable for use as a viscosity modifier (e.g., in a viscosity modifying composition or the like) or a lubricant (e.g., in a lubricant composition or the like) or in a biomedical device (such as, for example, an artificial joint or the like), in a vehicle (such as, for example, an automobile or the like), a boat or ship, a consumable (e.g., an eating device (e.g., a fork, a spoon, a knife, etc.) or the like), a container, a securing device (such as, for example, a tie or the like), a tray, as a separator in an electrochemical device (such as, for example, a battery or the like) or for use in a membrane for filtration (such as, for example, a filter for removing metals from water via chelation), or the like.

[0069] In various examples, a polymer functionalized substrate (such as, for example, a composition comprising one or more polymer functionalized substrate(s), an article of manufacture comprising one or more polymer functionalized substrates(s), or the like) exhibits one or more desirable propert(ies) (which may independently be surface propert(ies), such as for example, a desirable friction (such as, for example, lower friction compared to thesame substrate, which is not functionalized, relative to the same material), a desirable viscosity friction (such as, for example, lower or higher viscosity friction compared to the same substrate, which is not functionalized), antifouling behavior, antimicrobial behavior, antiviral behavior, stimuli responsive behavior, desirable wettability, hydrophobic behavior, chemoselectivity, scratch / abrasion resistance, desirable adhesion, or the like. Stimuli response includes, but is not limited to, brush polymers that undergo a change one or more surface propert(ies) in response to an external stimulus, such as, for example, temperature, pH, ionic strength, solvent, light, or the like. For example, PNIPAAM brushes undergo a transition from hydrophilic to hydrophobic as temperature increases.

[0070] In an aspect, the present disclosure provides methods of making polymer functionalized substrates. In various examples, polymer groups or the like are grafted from a surface of a substrate. In various examples, a method comprises (or is) a radical polymerization or radical polymerizations, or the like, or any combination thereof, any or all of which may be a surface-initiated polymerization. In various examples, a method forms a polymer functionalized substrate of the present disclosure. Non-limiting examples of methods of making polymer functionalized substrates are provided herein.

[0071] In various examples, a method of making a polymer functionalized substrate (e.g., a polymer functionalized substrate of the present disclosure) comprises (or consists essentially of or consists of) contacting a substrate (e.g., a substrate comprising one or more polymer(s)) with one or more monomer(s), one or more photocatalyst(s), one or more chain transfer agent(s), and optionally, one or more solvent(s) (e.g., forming which may be referred to as a precursor substate); and irradiating (or contacting or subjecting) at least a portion, substantially all, or all of a surface or the surfaces of the substrate with (or to) electromagnetic radiation. In various examples, a substrate is not also contacted with a chemical oxidant (such as, for example, ferrocenium tetrafluorob orate, silver triflate, or the like, or any combination thereof). In various examples, a method of making a polymer functionalized substrate (e.g., a polymer functionalized substrate of the present disclosure), comprises (or consists essentially of or consists of) irradiating (or contacting or subjecting) at least a portion, substantially all, or all of a surface or the surfaces of a substrate comprising one or more polymer(s) with one or more monomer(s), one or more photocatalyst(s), one or more chain transfer agent(s), and, optionally, one or more solvent(s) disposed on the at least a portion, substantially all, or all the surfaces of the substrate (forming which may be referred to as a precursor substate) with (or to) electromagnetic radiation. In various examples, a substrate is not also contacted with a chemical oxidant (such as, for example, ferroceniumtetrafluoroborate, silver triflate, or the like, or any combination thereof). In various examples, a polymer functionalized substrate is produced in a single irradiation step.

[0072] In various examples, a method is a method of modifying one or more surface propert(ies) of at least a portion of or all of a surface or all of the surfaces of a substate. In various examples, method provides a surface or surfaces of a substrate with antibacterial activity, antiviral activity, antifouling activity, hydrophobicity, stimuli responsive activity, or the like, or any combination thereof.

[0073] In various examples, a method comprises (or is) a radical polymerization or radical polymerizations, or the like, or any combination thereof, any or all of which may be a surface-initiated polymerization. In various examples, a method comprises (or is) a surface- initiated hydrogen atom transfer (HAT)-reversible addition-fragmentation chain transfer (RAFT) polymerization(s), or the like, or any combination thereof.

[0074] Various substrates can be used. Non-limiting examples of substrates are provided herein. In various examples, a substrate is a substrate disclosed herein. In various examples, a substrate comprises one or more (e.g., a plurality of) carbon-hydrogen group(s) (e.g., comprising carbon-hydrogen bond(s)), which may be neutral electron density carbonhydrogen bonds (e.g., neutral electron density carbon-hydrogen group(s)) and / or hydridic carbon-hydrogen bonds (e.g., hydridic carbon-hydrogen groups), disposed on a surface of the substrate. In various examples, a majority, substantially all, or all of the carbon-hydrogen bonds (e.g., carbon-hydrogen bonds disposed on substantially all, or all of a surface or all of the surfaces (which may be exterior surface(s)) of a substrate are neutral electron density or hydridic carbon-hydrogen bonds or the like. In various examples, a substrate does not comprise (or does not only comprise) non-neutral carbon-hydrogen bonds and / or non- hydridic carbon-hydrogen bonds. In various examples, a substrate does not comprise (or only comprise) (or is not) polyethyleneterephthalate (such as, for example, a substrate is not Mylar® (biaxially oriented polyethylene terephthalate) or the like), silicate glass (e.g., only silicate glass), silica glass, a silicon wafer, or the like. In various examples, a substrate does not comprise a hydrocarbon (e.g., octadecane) monolayer disposed on a surface of a substrate (such as, for example, Mylar® (biaxially oriented polyethylene terephthalate), silica glass, or the like).

[0075] In various examples, a substrate is not subjected to any pretreatment prior contacting the substrate with monomer(s), photocatalyst(s), chain transfer agent(s), and optionally, one or more solvent(s). Non-limiting examples of pretreatment include treatment with a chemical oxidant (such as, for example, ferrocenium tetrafluoroborate, silver triflate,or the like, or any combination thereof), treatment with UV light, treatment with gamma rays, treatment with plasma, treatment with high energy electrons, or the like, or any combination thereof. In various examples, a substrate is not oxidized or the like prior to formation of the polymer groups. In various examples, a substrate is not treated with strong acid, a plasma (such as, for example, an oxygen plasma or the like), subjected to gamma rays or high energy particles (e.g., electrons or the like) or the like, or any combination thereof prior to formation of the polymer groups. In various examples, a substrate is not photosensitized (such as, for example, contacted (e.g., soaked or the like) with one or more photosensitizer(s)) or the like prior to formation of the polymer groups. In various examples, a substrate does not comprise a surface radical initiator group (such as, for example, a group formed from a radical initiator or the like) prior to formation of the polymer groups. In various examples, a substrate does not comprise surface groups comprising a preformed polymer group or preformed polymer group or the like. In various examples, a polymer group does not comprise a preformed polymer group (such as, for example, a polymer group formed from a preformed polymer or the like) or the like.

[0076] Various monomers can be used. In various examples, a single monomer is used. A combination of monomers may be used. In various examples, two or more different (e.g., structurally different and / or compositionally different) monomers are used. In various examples, a monomer is a radically reactive (e.g., radically polymerizable or the like) monomer. In various examples, a monomer is not a triplet quencher (such as, for example, styrene or the like) or the like.

[0077] Non-limiting examples of monomers include acrylates, methacrylates, acrylamides, methacrylamides, vinyl acetates, maleic anhydrides, maleimides, olefins, structural analogs thereof, and the like, and any combination thereof. In various examples, a monomer is a zwitterionic monomer (e.g., comprising one or more zwitterionic group, such as, for example, a group comprising at least one cationic group and at least one anionic group). Non-limiting examples of zwitterionic monomers include sulfobetaine zwitterionic monomers (e.g., monomers comprising one or more sulfobetaine group(s)), phosphobetaine monomers (e.g., monomers comprising one or more phosphobetaine group(s)), carboxybetaine monomers (e.g., monomer comprising one or more carbobetaine group(s)), structural analogs thereof, and the like, and any combination thereof. In various examples, a monomer is a polyethylene glycol (PEG) monomer (e.g., a monomer comprising one or more PEG group(s) or the like) or the like. In various examples, a monomer (such as, for example, a monomer disclosed herein) is structural with one or more sulfobetaine group(s), one ormore phosphobetaine group(s), one or more carbonbetaine group(s), one or more PEG group(s), or the like, or any combination thereof.

[0078] Non-limiting examples of monomers include acrylates (which may comprise zwitterionic group(s), polyethylene glycol (PEG) group(s), or the like, or any combination thereof), methacrylates (which may comprise zwitterionic group(s), PEG group(s), or the like, or any combination thereof), acrylamides, methacrylamides, vinyl acetates, maleic anhydrides, maleimides, olefins, monomers comprising one or more zwitterionic group(s), monomers comprising one or more PEG group(s), and other radically polymerizable monomers, and the like, structural analogs thereof, and any combination thereof. In various examples, a monomer is a zwitterionic monomer (such as, for example, 3-((2- (acryloyloxy)ethyl)dimethylammonio)propane-l -sulfonate or the like) or the like. In various examples, a monomer is a silane-containing monomer, such as, for example, a silane- containing monomer comprising the following structure:structural analog thereof, or the like.

[0079] Various amounts of monomer(s) can be used. In various examples, the monomer(s) is / are present (e.g., independently or in the aggregate) at about a concentration of about 1 M to about 7 M (e.g., neat), including all 0.1 M values and ranges therebetween. In various examples, the monomer(s) is / are present, collectively, at about 50 to about 1000 equivalents (e.g., relative to 1 equivalent of the CTA(s) or the like, such as, for example, 1 equivalent of CTA(s) or the like)), including all 0.1 equivalent values and ranges therebetween.

[0080] Various photocatalysts can be used. In various examples, a single photocatalyst is used. Combinations of photocatalysts may be used. In various examples, two or more different (e.g., structurally different and / or compositionally different) photocatalysts are used. In various examples, a photocatalyst is (or the photocatalysts are) hydrogen atom transfer catalysts or the like, or any combination thereof. Without intending to be bound by any particular theory, it is desirable that a photocatalyst absorbs at least a portion of electromagnetic radiation. Non-limiting examples of photocatalysts include aromatic ketones(such as, for example, benzophenones, which may be structural benzophenones, and the like), thioxanthones, xanthene dyes (such as, for example, fluorescein, Eosin Y,, where x is independently at each occurrence 0, 1, 2, or 3, the R1group(s) and R2(groups) and R3group are independently at each occurrence chosen from -H, -OH, alkoxy groups (such as, for example, methoxy groups or the like), alkylamine groups, aryl groups, thiol groups, thioether groups, halide groups (e.g., -F, -Cl, and -Br), fluorinated alkyl groups (such as, for example, fluorinated alkyl groups (e.g., a trifluoromethyl group or the like) or the like), and the like, and any combinations thereof, and Ar is an aryl group or the like), structural analogs thereof, and the like), polyoxometalates (such as, for example, poly oxotungstates (e.g., tungsten anions, such as, for example, decantungstate anions (e.g., (NBU4)4 (W10O32), Na4(Wio032, W10O34", structural analogs thereof, and the like), structural analogs thereof, and the like), uranyl salts (or uranyl cations and the like) (such as, for example, (UChXCICUX, (UO2)(NOs)2, structural analogs thereof, and the like), metal-oxo porphyrins (such as, for example, , antimony-oxo tetra-(p-methoxyphenyl)-porphyrin (is an aryl group and M is a metal (e.g., manganese, antimony, or the like), and structural analogs thereof, and the like), tris(amino)cyclopropenium radical dications, structural analogs thereof, and the like, and any combination thereof.

[0081] In various examples, at least a portion or all the photocatalysts(s) comprise (or consist of) the following structure:structrual analog thereof, or the like), or a structural analog thereof or the like. In various examples, x is independently at each occurrence 0, 1, 2, or 3. In various examples, the R1group(s) and R2(groups) are independently at each occurrence chosen from -H, -OH, alkoxy groups (such as, for example, methoxy groups or the like), alkylamine groups, aryl groups, thiol groups, thioether groups, halide groups (e.g., -F, -Cl, and -Br), fluorinated alkyl groups (such as, for example, fluorinated alkyl groups (e.g., a trifluoromethyl group or the like) and the like), and the like, and any combinations thereof. In various examples, the R1and R2groups are independently at each occurrence in the ortho, meta, or para positions of the phenyl ring. In various examples, a photocatalyst comprises multiple (e.g., two or three) R1groups and / or multiple (e.g., two or three) R2groups. In various examples, one or both of the phenyl rings are structural (e.g., multiply substituted) or not substituted.

[0082] In various examples, at least a portion or all the photocatalysts(s) comprise (or consist of) the following structure:thereof, or the like), where Y is S, O, or the like, or a structural analog thereof, or the like. In various examples, x is independently at each occurrence 0, 1, 2, or 3. In various examples, the R1group(s) and R2(groups) are independently at each occurrence chosen from -H, -OH, alkoxy groups (such as, for example, methoxy groups or the like), alkylamine groups, aryl groups, thiol groups, thioether groups, halide groups (e.g., -F, -Cl, and -Br), fluorinated alkyl groups (such as, for example, fluorinated alkyl groups (e.g., a trifluoromethyl group or the like) or the like), and the like, and any combinations thereof. In various examples, the R1and R2groups are independently at each occurrence in the ortho, meta, or para positions of the phenyl ring. In various examples, a photocatalyst comprises multiple (e.g., two or three) R1groups and / or multiple (e.g., two or three) R2groups. In various examples, one or both of the phenyl rings are substituted (e.g., multiply substituted) or not substituted.

[0083] Various amounts of photocatalyst(s) can be used. In various examples, the photocatalyst(s) is / are present (independently and / or in the aggregate) at a concentration of about 10 mM to about 80 mM, including all 0.1 mM values and ranges therebetween. In various examples, the photocatalyst(s) is / are present, collectively, at about 1 equivalent (e.g., relative to the CTA(s) or the like, such as, for example, 1 equivalent of CTA(s) or the like).

[0084] Various chain transfer agents can be used. Without intending to be bound by any particular theory, it is considered that a chain transfer agent enables chain transfer and / or photocatalyst turnover. In various examples, a single chain transfer agent is used. A combination of chain transfer agents may be used. In various examples, two or more different (e.g., structurally different and / or compositionally different) chain transfer agents are used. Non-limiting examples of chain transfer agent(s) include disulfide derivatives of trithiocarbonates, dithioates, diothiocarbamates, xanthates, a Z group in a RAFT polymerization, and the like, and any combination thereof. In various examples, a chain transfer group comprises a Z group of a (or suitable for use in) reversible additionfragmentation chain transfer (RAFT) polymerization. Examples of suitable Z groups of a RAFT polymerization are known in the art (such as, for example, trithiocarbonate groups, dithioate groups, dithiocarbamate groups, xanthate groups, structural analogs thereof, and the like).

[0085] In various examples, at least a portion or all the chain transfer agent(s) comprise (or consist of) the following structure:structural analog thereof or the like. In various examples, R3is independently at each occurrence chosen from alkyl groups (such as, for example, Ci to C20 alkyl groups, including all integer number of carbons and ranges therebetween, or the like), aryl groups, -SR3groups, -OR3groups, -N(R3)2 groups, for example, where R3is independently at each occurrence an alkyl group, an aryl group, and structural analogs thereof, and the like. In various examples, one or more or all of the chain transfer agent(s) comprise(s) or consist(s) of) the following structure:(such as, for example,, or a structural analog thereof, or the like) ,structural analog thereof or the like. In various examples, R3is independently at each occurrence chosen from alkyl groups(such as, for example, Ci to C20 alkyl groups, including all integer number of carbons and ranges therebetween, or the like), aryl groups, and the like, and any combinations thereof).

[0086] Various amounts of chain transfer agent(s) can be used. In various examples, the chain transfer agent(s) is / are present (independently and / or in the aggregate) at a concentration of about 10 mM to about 80 mM, including all 0.1 mM values and ranges therebetween. In various examples, the chain transfer agent(s) is / are present, collectively, at about 1 equivalent (e.g., relative to the CTA(s), such as, for example, 1 equivalent of CTA(s)).

[0087] Various solvents may be used. In various examples, a single solvent is used. A combination of solvents may be used. In various examples, two or more different (e.g., structurally different and / or compositionally different) solvents are used. In various examples, a solvent is a solvent that desirably solubilizes the monomer(s), photocatalyst(s), and CTA(s). Non-limiting examples of solvents include alcohols (such as, for example, methanol, ethanol, structural analogs thereof), ethers (such as, for example, dioxane, tetrahydrofuran, diethyl ether, structural analogs thereof, and the like), formamides (such as, for example, dimethylformamide, structural analogs thereof, and the like), water, N- alkylpyrrolidones (such as, for example, N-methylpyrrolidone, structural analogs thereof, and the like), fluoroalkanes (such, as for example, di chloroethane or the like), and the like, and any combination thereof. In various examples, at least one or more or all of the solvent(s) is / are hydridic solvent(s) (such as, for example, dioxane, tetrahydrofuran, dimethylformamide, N-methylpyrrolidone, a structural analog thereof, or the like, or any combination thereof) or the like.

[0088] Various electromagnetic radiation sources and wavelengths can be used. In various examples, electromagnetic radiation is provided by a lamp or lamps, a bulb or bulb, a laser or lasers, a light-emitting diode or light emitting diodes, or the like, or any combination thereof. In various examples, the electromagnetic radiation comprises one or more wavelength(s) of about 200 nm to about 700 nm, including all 0.1 nm values and ranges therebetween.

[0089] Irradiating (e.g., contacting or subjecting) may be patterned. In various examples, irradiating (e.g., contacting or subjecting) at least a portion, substantially all, or all of a surface or the surfaces of the substrate with the electromagnetic radiation is carried out in predetermined pattern. In various examples, the contacting (or subjecting) at least a portion, substantially all, or all of a surface or the surfaces of the substrate with the electromagnetic radiation is carried lithographically, in a direct write mode, or the like.

[0090] Contacting and / or irradiating (e.g., contacting or subjecting) may be repeated a desired number of times. In various examples, at least a portion or all the contacting(s) or the irradiating(s), or both, is / are carried out with the same monomer(s), photocatalyst(s), and chain transfer agent(s). In various examples, at least a portion or all the contacting(s) or the irradiating(s), or both, is / are carried out with one or more different (e.g., structurally different, different concentration, or the like) monomer(s) or photocatalyst(s) or chain transfer agent(s), or any combination thereof.

[0091] A method (e.g., an irradiation, a polymerization reaction, or the like) can be performed under various reaction conditions. A method (e.g., an irradiation, a polymerization reaction, or the like) can comprise one or more step(s) and each step can be performed under the same or different reaction conditions as other steps. A method (e.g., an irradiation, polymerization reaction, or the like) can be carried out at various temperatures. In various examples, a polymerization reaction is carried out at about room temperature (e.g., from about 20 °C to about 30 °C, including all 0.1 °C values and ranges therebetween), below room temperature (e.g., below about room temperature, such as for example, from about -78 °C to about room temperature, including all 0.1 °C values and ranges therebetween), or above room temperature (e.g., above room temperature up to or about a boiling point of the solvent(s), if present) (e.g., room temperature to about 100 °C or above, or any combination thereof (e.g., where each irradiation, polymerization reaction, or the like) is performed at a different temperature as other steps). In various examples, a method (e.g., an irradiation, polymerization reaction, or the like) is carried out at about -78 °C to about 100 °C, including all 0.1 °C values and ranges therebetween.

[0092] A method (e.g., an irradiation, polymerization reaction, or the like) can be carried out at various pressures. In various examples, a method (e.g., an irradiation, polymerization reaction, or the like) is carried out at atmospheric pressure (e.g., 1 standard atmosphere (atm) at sea level), at greater than atmospheric pressure (e.g. heating in a sealed pressurized reaction vessel and the like), at below atmospheric pressure (e.g., under vacuum (e.g., from about 1 mTorr or less to about 100 mTorr or less, including all 0.1 mTorr values and ranges therebetween) (e.g., about 100 mTorr or less, about 50 mTorr or less, about 10 mTorr or less, or about 1 mTorr or less) and the like), or any combination thereof (e.g., where each step is performed at a different pressure as other steps).

[0093] A method (e.g., an irradiation, polymerization reaction, or the like) can be carried out for various times. The reaction time can depend on factors such as, for example, temperature, light intensity, irradiation time(s), efficiency of the photopolymerization, desired conversion of monomer, concentration of monomer, or the like, or any combination thereof. In various examples, reaction times range from about seconds (e.g., about 10 seconds) to greater than about 24 hours, including all integer second values and ranges therebetween, or any combination thereof (e.g., where each step is performed at the same time or a different time as other steps).

[0094] In various examples, a method comprises a desirable conversion percentage of the monomer(s). In various examples, at least about 5% or more, at least about 10% or more, at least about 25% or more, or at least about 50% or more of the monomer(s) is / are polymerized. In various examples, about 5% to about 100% of the monomer(s), including all 0.1% values and ranges therebetween, are polymerized. Conversion percentage can be determined by methods known in the art. In various examples, conversion percentage is determined by chromatography (gas-chromatography (GC) (e.g., gas-chromatography-mass spectrometry or the like), liquid chromatography (e.g., high-performance liquid chromatography (HPLC) or the like), nuclear magnetic resonance (NMR) spectroscopy (e.g.,JH NMR,13C NMR, or the like), or the like or any combination thereof.

[0095] In an aspect, the present disclosure provides uses of functionalized substrates (e.g., polymer functionalized substrates or the like) of the present disclosure. Non-limiting examples of uses of functionalized substrates (e.g., polymer functionalized substrates or the like) are provided herein.

[0096] A polymer functionalized substrate can have various uses. In various examples, a polymer functionalized substrate is suitable and / or configured for use as a viscosity modifier, a lubricant, or the like.

[0097] In various examples, a composition comprises one or more functionalized substrate(s) of the present disclosure. Non-limiting examples of compositions include viscosity modifying compositions, lubricant compositions, paints, stains, or other coating compositions, and the like.

[0098] In various examples, a polymer functionalized substrate is suitable and / or configured for use in a medical or biomedical device (such as, for example, to provide a low friction surface / coating (e.g., for an artificial joints comprising cross-linked polyethylene or the like)), or an antimicrobial or antiviral surface / coating, marine applications (such as, for example, for antifouling coatings), antimicrobial and / or antiviral coatings for high touch surfaces (such as, for example, food trays on airplanes or the like), battery applications (such as, for example, to provide a wettable surface / coating for (or improve the wettability of) a battery membrane in electrolyte, to aid in suppressing dendrite formation, or the like, or any combination thereof), upcycling post-consumer plastics (e.g., by functionalizing functionalize post-consumer polyethylene), food packaging (e.g., functionalizing an inner surface of a plastic bottle with hydrophobic coating to minimize food waste or the like), to provide a paintable polyethylene or the like surface (such as, for example, a car part (e.g., a bumpers) or other automotive component or material), in a membranes for a chemically selective filtration (such as, for example, removing metal(s) from water (e.g., for use in semiconductor manufacturing or the like) or the like), to provide scratch resistant coatings for polyethylene or the like.

[0099] In various examples, an article of manufacture comprises one or more polymer functionalized substrate(s) of the present disclosure. In various examples, at least a portion, substantially all, or all of the polymer functionalized substrate(s) are made by a method of the present disclosure. In various examples, all of the polymer functionalized substrates are the same. In various examples, at least two or more of the polymer functionalized substrates are different (e.g., structurally and / or compositionally different). In various examples, an article of manufacture is a biomedical device (such as, for example, an artificial joint or the like), a marine article (such as, for example, a boat / ship hull, a component, or the like), an automotive article (such as, for example, an automotive part (e.g., a door, upholstery, a fender, a bumper, a hood, or the like), a consumable (e.g., an eating device (e.g., a fork, a spoon, a knife, etc.) or the like), a container, a securing device (such as, for example, a tie or the like), a tray, a membrane (e.g., a polyolefin membrane or the like) (such as, for example, an electrochemical (e.g., battery or the like) membrane (such as, for example, a polyolefin membrane or the like), a filtration membrane, or the like), or the like.

[0100] In various examples, an article of manufacture exhibits one or more desirable propert(ies). In various examples, an article of manufacture exhibits (the polymer functionalized substrate(s) exhibit(s)) desirable friction (such as, for example, low friction compared to the same article of manufacture without the polymer functionalized substrate(s)); antifouling activity or behavior; antimicrobial activity or behavior; antiviral activity or behavior, desirable wettability; hydrophobicity or hydrophobic behavior; chemoselectivity; stimuli responsive activity or behavior, scratch / abrasion resistance; or the like, or any combination thereof.

[0101] The following Statements provide examples of polymer functionalized substrates, methods of making polymer functionalized substrates, and uses of polymer functionalized substrates of the present disclosure:Statement 1. A polymer functionalized substrate comprising: a substrate comprising a polymer; and a plurality of polymer groups (which may be referred to as polymer brushes or the like), where the polymer groups are disposed on (e.g., independently at each occurrence covalently bound or the like to) at least a portion of, substantially all, or all of a surface (such as, for example, an exterior surface of a substrate or the like) or all surfaces (such as, for example, exterior surfaces of polymer layer or the like) of the substrate (such as, for example, the polymer of the substrate or the like).Statement 2. A polymer functionalized substrate according to Statement 1, where the substrate is a polymer or comprises a polymer layer (such as, for example, a polymer layer which may be an exterior polymer layer or the like) or the like.Statement 3. A polymer functionalized substrate according to Statement 2, where the polymer comprises (or is) a polyolefin, a polystyrene, a polyether, a polyamide, a structural analog thereof, or a copolymer thereof, any of which may be crosslinked, or the like, or a combination thereof.Statement 4. A polymer functionalized substrate according to Statement 3, where the polyolefin is chosen from polyethylene, polypropylene, structural analogs thereof, and copolymers thereof, any of which may be crosslinked, and the like, and any combination thereof.Statement 5. A polymer functionalized substrate according to Statement 4, where the polyethylene is chosen from high-density polyethylene, low-density polyethylene, linear high-density polyethylene, linear low-density polyethylene, structural analogs thereof, and copolymers thereof, any of which may be crosslinked, and the like, and any combination thereof.Statement 6. A functionalized substate according to any one of the preceding Statements, where the polymer groups are chosen from polyacrylate groups, polymethacrylate groups, polyacrylamide groups, polymethacrylamide groups, polyvinyl acetate groups, polymaleic anhydride groups, polymaleimide groups, polyolefin groups, polymer groups comprising one or more PEG group(s) (such as, for example,the like, where x is 1 to 150, including all integer values and ranges therebetween, and z is Ito 10,000, including all integer values and ranges therebetween , or and the like), zwitterionic polymer groups (such as, for example,, where ZG is a zwitterionic group (such as, for example,independently at each occurrence an alkyl group or the like (e.g., a sulfobetaine group or the like)), copolymers thereof, structural analogs thereof, and the like, and any combination thereof.Statement 7. A polymer functionalized substrate according to any one of the preceding Statements, where the functionalized substrate comprises about 0.05 chains / nm2to about 6 chains / nm2, including all 0.01 chains / nm2values and ranges therebetween (e.g., greater than about 0.2 chains / nm2to about 2 chains / nm2, 0.3 chains / nm2to about 2 chains / nm2, 0.5 chains / nm2to about 2 chains / nm2, greater than about 0.2 chains / nm2to about 4 chains / nm2, 0.3 chains / nm2to about 4 chains / nm2, 0.5 chains / nm2to about 4 chains / nm2, greater than about 0.2 chains / nm2to about 6 chains / nm2, 0.3 chains / nm2to about 6 chains / nm2, 0.5 chains / nm2to about 6 chains / nm2, about 0.5 chains / nm2, about 0.75 chains / nm2).Statement 8. A polymer functionalized substrate according to any one of the preceding Statements, where the polymer groups independently at each occurrence comprise (or the polymer groups form a polymer group layer comprising) a dimension substantially normal or normal to a plane defining a surface of the substrate (such as, for example, a thickness or the like) of about 10 nm (nm = nanometer(s)) to about 1000 nm, including all 0.1 nm values and ranges therebetween (e.g., about 50 nm to about 500 nm).Statement 9. A polymer functionalized substrate according to any one of the preceding Statements, where at least a portion, substantially all, or all the polymer groups form a predetermined pattern on at least a portion, substantially all, or all of a surface (or all the surfaces) of the substrate.Statement 10. A method of making a polymer functionalized substrate (e.g., a polymer functionalized substrate of the present disclosure, such as for example, a polymer functionalized substrate of any one of Statements 1 to 9) comprising: contacting a substrate (e.g., a substrate comprising a polymer) with one or more monomer(s), one or more photocatalyst(s), one or more chain transfer agent(s), and optionally, one or more solvent(s); and irradiating (or contacting or subjecting) at least a portion, substantially all, or all of a surface or the surfaces of the substrate with (or to) electromagnetic radiation, where the functionalized substrate is formed.Statement 11. A method according to Statement 10, where the monomer(s) is / are chosen from acrylates (which may comprise zwitterionic group(s), PEG group(s), or the like, or any combination thereof), methacrylates (which may comprise zwitterionic group(s), PEG group(s), or the like, or any combination thereof), acrylamides, methacrylamides, vinyl acetates, maleic anhydrides, maleimides, olefins, monomers comprising one or more zwitterionic group(s), monomers comprising one or more PEG group(s), and other radically polymerizable monomers, and the like, structural analogs thereof, and any combination thereof.Statement 12. A method according to Statement 10 or 11, where the monomer(s) is / are present at about a concentration of about 1 M to about 7 M (e.g., neat), including all 0.1 M values and ranges therebetween.Statement 13. A method according to any one of Statements 10 to 12, where the photocatalysts(s) is / are chosen from aromatic ketones (such as, for example, benzophenones, which may be structural benzophenones, and the like), thioxanthones, xanthene dyes, polyoxometalates, uranyl salts (such as, for example, uranyl cations or the like), tungsten anions, metal-oxo porphyrins, tris(amino)cyclopropenium radical dications, structural analogs thereof, and the like, and any combination thereof.Statement 14. A method according to any one of Statements 10 to 13, where at least a portion or all the photocatalysts(s) comprise (or consist of) the following structure:structural analog thereof, where x is independently at each occurrence 0, 1, 2, or 3, andR1group(s) and R2(groups) are independently at each occurrence chosen from -H, -OH, alkoxy groups (such as, for example, methoxy groups or the like), alkylamine groups, aryl groups, thiol groups, thioether groups, halide groups (e.g., -F, -Cl, and -Br), fluorinated alkyl groups (such as, for example, fluorinated alkyl groups (e.g., a trifluoromethyl group or the like) or the like), and the like, and any combinations thereof.Statement 15. A method according to any one of Statements 10 to 14, where the photocatalyst(s) is / are present (independently and / or in the aggregate) at a concentration of about 10 mM to about 80 mM, including all 0.1 mM values and ranges therebetween. Statement 16. A method according to any one of Statements 10 to 15, where the chain transfer agent(s) is / are chosen from disulfide derivates of trithiocarbonates, dithiocarbonates, diothiocarbamates, xanthanates, and the like, and any combination thereof.Statement 17. A method according to any one of Statements 10 to 16, where at least a portion or all the photocatalysts(s) comprise (or consist of) the following structure:structural analog thereof, or the like, where R3is independently at each occurrence chosen from alkyl groups (such as, for example, Ci to C20 alkyl groups,including all integer number of carbons and ranges therebetween, or the like), aryl groups, - SR3groups, -OR3groups, -N(R3)2 groups, for example, where R3is independently at each occurrence an alkyl group or an aryl group, structural analogs thereof, and the like, and any combinations thereof.Statement 18. A method according to any one of Statements 10 to 17, where the chain transfer agent(s) is / are present at a concentration of about 10 mM to about 80 mM, including all 0.1 mM values and ranges therebetween.Statement 19. A method according to any one of Statements 10 to 18, where the electromagnetic radiation comprises one or more wavelength(s) of about 200 nm to about 700 nm, including all 0.1 nm values and ranges therebetween.Statement 20. A method according to any one of Statements 10 to 19, where the irradiating (e.g., contacting or subjecting) at least a portion, substantially all, or all of a surface or the surfaces of the substrate with the electromagnetic radiation is carried out in predetermined pattern.Statement 21. A method according to any one of Statements 10 to 20, where the solvent(s) is / are chosen from ethers (such as, for example, dioxane, tetrahydrofuran, diethyl ether, and the like), water, fluoroalkanes (such as, for example, dichloroethane or the like), and the like, and any combination thereof.Statement 22. A method according to any one of Statements 10 to 21, where the contacting and / or irradiating is / are repeated a desired number of times.Statement 23. An article of manufacture comprising one or more polymer functionalized substrate(s) of the present disclosure (e.g., a polymer functionalized substrate or substrates or the like of the present disclosure, such as for example, a polymer functionalized substrate or substrates or the like of any one of Statements 1 to 9, a polymer functionalized substrate or substrates or the like made by a method of the present disclosure (e.g., a polymer functionalized substrate or substrates or the like made by a method of any one of Statements 10 to 22).Statement 24. An article of manufacture according to Statement 23, where the article of manufacture is chosen from biomedical devices, marine articles (such as, for example, boat / ship hulls, components, or the like), automotive articles (such as, for example, automotive parts (e.g., doors, upholstery, fenders, bumpers, hoods, or the like), consumables (eating devices (e.g., forks, spoons, knives, etc.) or the like, containers, trays, membranes (such as, for example, electrochemical (e.g., battery or the like) membranes, filtration membranes, etc.), and the like.Statement 25. An article of manufacture according to Statement 23 or 24, where the article of manufacture exhibits (the polymer functionalized substrate(s) exhibit(s)) one or more of the following: desirable friction (such as, for example, low friction compared to the same article of manufacture without the polymer functionalized substrate(s)); antifouling behavior; antimicrobial behavior; wettability; hydrophobic behavior; chemoselectivity; scratch / abrasion resistance; or the like.

[0102] The steps of the methods described in the various examples disclosed herein are sufficient to produce one or more polymer functionalized substrate(s) or carry out a method of the present disclosure. Thus, in various examples, a method consists essentially of a combination of the steps of the methods disclosed herein. In various other examples, a method consists of such steps.

[0103] The following Examples are presented to illustrate the present disclosure. The Examples are not intended to be limiting in any manner.EXAMPLE 1

[0104] This example provides a description of polymer functionalized substrates of the present disclosure and methods of making and using same.

[0105] Direct Functionalization of Polyethylene Surfaces with High -Density Polymer Brushes. Introducing functionality into PE surfaces is a longstanding challenge in polymer science, driven by the need for polymer materials with improved adhesion and antifouling properties. Herein, we report surface-initiated hydrogen atom transfer-reversible additionfragmentation chain transfer (SI HAT -RAFT) as a robust method to grow high-density brush polymers from PE surfaces. It was demonstrated that under mild conditions, direct initiation from the C — H bonds of PE surfaces allows for the graft polymerization of a variety of (meth)acrylate monomers. The resulting polymer brushes reached several hundred nanometers in thickness with densities of ca. 0.62 chains / nm2, compared to the current standard of -0.28 chains / nm2. Finally, it was shown that the instant methods are capable of dramatically improving the adhesive properties of PE surfaces. This work enables the preparation of PE with diverse surface functionalities, which is expected to be useful in biomedical, industrial, and battery applications.

[0106] Surface-initiated HAT-RAFT (SI HAT -RAFT) was demonstrated as a method for the synthesis of high-density brush polymers on PE surfaces. Studies were initiated by layering a solution of benzophenone derivative (1), bis(trithiocarbonate) disulfide species (2), tert-butyl acrylate, and dioxane on top of a high-density polyethylene (HDPE) film andcovering it with a glass slide before irradiating with visible light from a compact fluorescent light (Figure 2a). HDPE was chosen as a starting point due to its attractive bulk properties and wide range of potential applications. Dioxane, a solvent with suitably hydridic C — H bonds for HAT-RAFT, was selected because surface-initiated RAFT systems typically require a sacrificial chain transfer agent; dioxane-initiated chains in solution likely promote surface polymerization by facilitating chain transfer in surface-bound polymer chains. Following irradiation, carbonyl and C — O bond stretches were detected in the IR, indicating that poly( / c / 7-butyl acrylate) (P'BA) was successfully installed on the surface of PE (Figure 2b). Upon basic hydrolysis of P'BA to poly(sodium acrylate) (PNaA), the static water contact angle of the surface decreased from 98° to 63°, indicating a dramatic increase in the hydrophilicity of the surface (Figure 2c).

[0107] Control experiments were carried out to verify that the polymer observed on the surface was in fact grafted covalently via the HAT -RAFT process. Free P'BA drop-cast onto an HDPE surface washed away easily, suggesting no adhesion of P'BA to HDPE in the absence of covalent bonds between the surface and the grafted polymer (Table 1).

[0108] Table 1. SI HAT-RAFT ControlsStrong IR stretch at 1730 cmStandard Conditions +Drop cast PBuA onto HDPEThermal RAFTNo lightNo disulfidePET instead of HDPE

[0109] Additionally, subjecting HDPE to thermal RAFT polymerization conditions yielded no polymer on the surface, confirming that generation of radicals alone is not enough to graft from HDPE. It was also found that under standard SI HAT -RAFT conditions, but in the absence of light, polymerization does not proceed.

[0110] Interestingly, under normal SI HAT -RAFT conditions but in the absence of disulfide, negligible polymer is observed by IR (Table 1). This suggests that despite the relatively high concentration of photocatalyst as compared to surface C — H bonds, the presence of disulfide to turn over the photocatalyst is crucial to attain significant amounts of brush polymer on the surface. In the proposed mechanism, the photocatalyst initiates chains both from the PE surface and from the dioxane in solution. Due to its ether functionality, the C — H bonds of dioxane are better polarity matched to the electrophilic photocatalyst than the C — H bonds of the PE surface. It is likely that in absence of the disulfide species, the photocatalyst does a small amount of initiation from the surface which is difficult to observe by IR, as well as a significant amount of the more kinetically favorable initiation from dioxane. Without the disulfide species to turn over the photocatalyst, it is not possible to achieve a significant amount of hydrogen atom abstraction from the PE surface. The X-rayphotoelectron spectroscopy (XPS) data showed sulfur from the disulfide in the grafted PE, supporting the presence of chains capped by the disulfide as in the solution HAT -RAFT process. Finally, PET (polyethylene terephthalate) was subjected to the instant standard surface polymerization conditions. Because the C — H bonds present in PET are acidic, we anticipated that the kinetic barrier to HAT would be too high for functionalization. As expected, no grafting of P'BA from a PET surface was observed, likely due to the electronpoor nature of the polyester. Together, these results suggest that surface-initiated HAT-RAFT is likely to proceed through our proposed mechanism and operates with similar kinetic selectivity to the solution polymerization. Visible light from the CFL excites the benzophenone photocatalyst, which abstracts a hydrogen atom from PE to generate a carbon centered radical. This radical adds into monomer before being capped by half of the disulfide (previously homolyzed under visible light). As chains continue to form on the surface, they enter the RAFT equilibrium, likely assisted by chains in solution initiated by dioxane. The consumed photocatalyst is turned over by single electron transfer (SET) and proton transfer (PT) to half of the disulfide species to begin the catalytic cycle again (Scheme 1).

[0111] Scheme 1. Hypothesized SI HAT -RAFT Mechanism.RAFT Equilibrium

[0112] Having shown that acrylates can be grown from a PE surface, better characterization of the brush polymers produced through microscopy experiments was sought. A silicon wafer was spin-coated with linear low-density polyethylene (LLDPE) to form the substrate and then grafted with P'BA. LLDPE was used for brush characterization due to its greater solution processability relative to HDPE. Atomic force microscopy (AFM) was used to assess brush thickness (Figure 3). For our LLDPE- -P'BA sample, we achieved a brush thickness of 260 nm. In uncontrolled, photosensitized systems, brush thicknesses up to160 nm have been achieved, and in ATRP polymerizations from PE copolymers, only ~50 nm of polymer brush have been attained. Excitingly, film thickness was tuned by controlling the reaction time; after 1 hour, a brush thickness of 34 nm, and after 4 hours, a 108 nm of brush thickness was achieved.

[0113] To investigate the brush density achieved by SI HAT -RAFT from PE, a swelling study of an LLDPE-g-PNaA surface was carried out (Figure 3b). According to classic scaling laws for polyelectrolyte brushes, the ratio of swollen to dry brush thickness can be described as a function of grafting density independent of molecular weight. After incubation in a pH 9 buffer solution for 10 minutes, the film thickness increased from 450 nm to 600 nm. This swelling ratio corresponds to a brush density of 0.62 chains / nm2. This high grafting density is also supported by following the water contact angle as polymerization proceeds. After an initial decrease over the first hour of polymerization, the water contact angle remains relatively constant. This behavior is consistent with brush polymers in the high-density regime. It is believed that the high grafting density is due to the photocatalyst turnover by the CTA, allowing for multiple cycles of hydrogen atom transfer. Currently, there are no other methods for grafting from PE surfaces that report such a high grafting density.

[0114] To demonstrate the diversity of PE surfaces accessible with SI HAT -RAFT, grafted polymer surfaces were prepared using a variety of acrylate and methacrylate monomers (Figure 4). Static water contact angles ranging from 63° to 86° are accessible, showing that hydrophilicity is tunable by the choice of monomer. Hydrophilicity can also be tuned by protonating or deprotonating the brushes. For example, in their protonated form, PAA brushes have a water contact angle of 72°. In their deprotonated, water-soluble PNaA form, the water contact angle falls to 63°. In the interest of synthesizing biomedically relevant surfaces, we examined a sulfobetaine zwitterion acrylate and a PEG acrylate. The sulfobetaine monomer has previously been shown to prevent bacteria from adhering to surfaces, making it a promising candidate for creating antifouling PEs. Poly(PEG) acrylates are currently of interest as a replacement for traditional linear PEG polymers, where they may be used to minimize nonspecific binding or to aid in drug delivery. PEG coated PEs are also desirable for their use in Li ion battery separators, where they have been shown to improve conductivity relative to HDPE alone. Excitingly, surface polymerization of a PEG acrylate from HDPE decreased the water contact angle of the surface to 65°, providing a highly hydrophilic surface. HDPE-g-poly(PEG acrylate) surfaces are expected to be promising candidates for applications in biomedical or battery science.

[0115] Finally, an important implication of modifying the surface properties of PE is improving its adhesion to other materials such as plastics, metals, or paint. To probe the ability of surface functionalized PE to adhere to paint, we prepared an HDPE-g-[PMMA-co- P"BuA] brush polymer surface and an unfunctionalized HDPE surface and coated both substrates with acrylic paint (Figure 5). Although the exact composition of most acrylic paints is proprietary, acrylic paint is most commonly composed of PMMA and P"BuA copolymers. For this reason, PMMA-co-P"BuA were selected as brushes for our paint test. Using a simple tape test, a dramatic improvement was observed in the ability of HDPE-g- [PMMA-co-P"BuA] to adhere to paint, in stark contrast with the unfunctionalized HDPE. It was proposed that the grafted surface was better able to interact with acrylic paint because of its similar chemical structure. In addition to adhesion to paint, we performed lap shear testing to probe the adhesion of surface modified PE to aluminum. Unfunctionalized LDPE is unable to form a lap joint with aluminum. In contrast, LDPE-g-PMMA adheres to aluminum with a shear strength of 1.1 ± 0.2 MPa. Improved adhesion of HDPE to paint and aluminum demonstrates the utility of SI HAT -RAFT as a platform for tuning the surface properties of PE.

[0116] A robust, highly diversifiable method to grow high-density brush polymers from PE surfaces was developed. The SI HAT -RAFT method presented achieved the highest reported brush thicknesses and densities grafting from PE surfaces, and we can access brush polymer surfaces composed of a wide variety of (meth)acrylate monomers. Finally, improvement in adhesion, an important surface property, upon grafting brush polymers from PE was demonstrated. Improving the surface properties of PE opens the door to using PE in applications including battery science, antimicrobial surfaces, and filtration. This work addresses the long-standing challenge in polymer science of facile and robust access to PEs with enhanced surface properties.

[0117] General Reagent Information. Tert-butyl acrylate ('BuA) (99%, Sigma Aldrich), methyl acrylate (MA) (99%, Sigma Aldrich), methyl methacrylate (MMA) (99%, Sigma Aldrich), / c / V-butyl methacrylate (T3uMA) (99%, Sigma Aldrich), and 1,4-di oxane (99.8%, Thermo Scientific) were dried over CaH2, distilled, and degassed via 3 freeze-pump-thaw cycles before storing in a nitrogen glovebox. Acrylic acid (AA) (99%, Sigma Aldrich), methacrylic acid (MAA) (99.5%, Acros Organics), and PEG acrylate (ATn= 480 g / mol, Sigma Aldrich) were passed over a plug of aluminum oxide (activated, basic, Brockmann Grade I, 58 Angstroms, Alfa Aesar) prior to use. High-density polyethylene (HDPE) (Dow ChemicalCompany, DMDA8904), low-density polyethylene (LDPE) (Scientific Polymer Products, Inc., CAT#042), and linear low-density polyethylene (LLDPE) (Sigma Aldrich, melt index 1.0 g / 10 min at 190 °C / 2.16 kg) were used as received. All other reagents were obtained from Sigma Aldrich, TCI, Oakwood, and Alfa Aesar and used as received. Magnesium turnings were ground with a mortar and pestle prior to use. Polymerizations were carried out under irradiation with a compact fluorescent light (Sylvania CF4OEL, 40 W, 120 V, 60 Hz, 2700 K, 2600 lumens). Glass microscope slides (25 mm x 75 mm x 1 mm) were purchased from VWR. Sheet aluminum was cut into 0.16 cm x 1 cm x 10 cm substrates for lap shear testing by the Cornell Laboratory of Atomic and Solid State Physics Professional Machine Shop.

[0118] General Analytical Information. Fourier-transform (FT-IR) spectra were on a Bruker Tensor II IR spectrometer equipped with a diamond Attenuated Total Reflectance (ATR) attachment. Static water contact angles were measured on a Rame-Hart 500 Goniometer using Milli-Q deionized water (15 pL). The average of at least 5 repetitive tests per sample was calculated. AFM measurements were conducted using an Oxford Instruments Cypher ES atomic force microscope equipped with an environmental scanner. Silicon tips (Oxford Instruments) with a resonance frequency of 300 kHz and a 26 N / m spring constant were used for the dry state, while the tips with a 70 kHz frequency and a 2 N / m spring constant were used for in-fluid analyses. The dry and wet thickness of brushes was measured through step-height measurements by AFM. To measure brush thickness, samples werescratched with a razor blade, and AFM height images were taken at the boundary between the scratched and non-scratched regions. Imaging was conducted in tapping mode, and the thickness of each sample was measured in three different regions. To determine the swelling ratio, samples were incubated in pH 9 buffer solution for 10 minutes and then the wet thickness of swollen brushes was measured. Dry brush thicknesses were also measured with a Keyence VK-X260 Laser-Scanning Profilometer. To measure brush thickness, samples of LLDPE spin-coated onto a silicon wafer were scratched with a razor blade, the depth of the scratch was measured before and after brush growth, and the difference in scratch depth before and after functionalization was recorded as the brush thickness. Samples for XPS were analyzed using a Thermo Scientific Nexsa G2 Spectrometer with operating pressure ca. IxlO'9Torr. Monochromatic Al Ka x rays (1486.6 eV) with photoelectrons collected from a 400 pm diameter analysis spot. Photoelectrons were collected at a 90° emission angle with source to analyzer angle of 54.7°. A hemispherical analyzer determined electron kinetic energy, using a pass energy of 200 eV for wide / survey scans, and 50 eV forhigh-resolution scans. A flood gun was used for charge neutralization of non-conductive samples. Nuclear magnetic resonance (NMR) spectra were recorded on a Bruker 500 MHz instrument at room temperature using CDCh as a solvent unless otherwise noted. Gel permeation chromatography (GPC) was performed using a Tosoh EcoSEC HLC 8320 GPC system with two SuperHM-M columns in series at a flow rate of 0.35 mL / min.Tetrahydrofuran was used as the eluent and number-average molecular weights (A / n), weightaverage molecular weights ( v), and dispersities (£)) were determined against polystyrene standards. Compression molding was performed using a 4120 Hydraulic Unit Carver press and stainless-steel die molds. Mylar® protective sheets, purchased from Carver, were used in between platens. Lap shear adhesion testing was carried out using a Shimadzu Autograph AGS-X tensile tester with a 5 kN load cell and a shear rate of 1.5 mm / min. Further experimental details are provided in the appropriate sections below.

[0119] General Photochemical Information. CFL Emission. The compact fluorescent light (CFL) employed in this study is a (Sylvania CF4OEL, 40 W, 120 V, 60 Hz, 2700 K, 2600 lumens) and was recorded using an Ocean Optics USB200 spectrophotometer. Light intensity. _The intensity of our CFL was measured using a ThorLabs Thermal Power Sensor Head, Surface Absorber, 0.19-20 pm, 2 mW-10 W, 25.4 mm. At 1 cm away from the CFL, the power of the CFL is 54 mW. Optical properties of glass slides. Borosilicate glass transmits from the infrared down to approximately 300 nm, which is sufficiently transparent to allow the full emission spectrum of the CFL used in this study to reach the substrate.

[0120] Synthesis of Reagents. Preparation of photocatalyst 1. Photocatalyst 1 was prepared according to a literature procedure. Preparation of chain transfer agent 2. CTA 2 was prepared according to the literature procedure.

[0121] Preparation of Polyethylene Substrates. Preparation of melt-pressed HDPE fdms. Using a Carver press, pellets of Dow HDPE (DMDA8904) were placed between two Mylar® sheets and melt pressed at 140 °C for 5 minutes at 2000 lbs (lb(s) = pound(s)) pressure before cooling to room temperature. 2 cm x 2 cm squares were cut from the cooled film for use as substrates. Preparation of melt-pressed LDP E fdms. In a Carver press between two Mylar® sheets, LDPE pellets were placed into a 1 mm x 3 cm x 8 cm stainless steel die and melt pressed at 140 °C for 5 minutes at 2000 lbs pressure before cooling to room temperature. 1 cm x 1 cm squares were cut from the cooled film for use as substrates. Preparation of spin- coated LLDPE fdms. Spin-coating procedure is modified from the procedure from O.Mellbring et al? A solution of 1 wt% LLDPE in toluene was heated to reflux and stirred untilhomogenous. A 1 cm x 1 cm piece of APTES functionalized silicon wafer was preheated on a stir plate at 100 °C for 2 min before being affixed with vacuum to the spin coater. Working quickly, a glass pasteur pipette was heated with a heat gun, and used to transfer 5 drops of hot LLDPE solution onto the wafer. The wafer spun at 1000 rpm for 30 seconds. LLDPE coated wafers were heated overnight at 110 °C before cooling to room temperature.

[0122] General Procedure for Surface-Initiated HAT -RAFT. In a nitrogen glovebox, photocatalyst 1 (2.80 mg, 10.0 pmol, 1 equiv), disulfide 2 (5.55 mg, 10.0 pmol, 1 equiv), monomer (2.0 mmol, 200 equiv), and solvent (0.25 mL) were combined in a one-dram vial. The resulting solution was pipetted onto a flat, 2 cm x 2 cm PE substrate which was laid on a glass microscope slide. The substrate was covered with a second glass microscope slide and irradiated 1 cm away from a compact fluorescent lamp with a fan for cooling. The reaction proceeded for 18 hours, at which time the lamp was turned off and the substrate removed from the glovebox. The substrate was washed in dichloromethane before drying with air. A general procedure for surface-initiated HAT -RAFT is shown in Scheme 2.

[0123] Scheme 2. General Procedure for Surface-Initiated HAT -RAFT.

[0124] All brush polymer films in this EXAMPLE were prepared according to the above General Procedure for Surface-Initiated HAT -RAFT unless otherwise specified. A depiction of a general reaction set up for surface-initiated HAT -RAFT is shown in FIG. 7. Disulfide 2 was selected because it is an easy to handle solid. However, any bis(trithiocarbonates) disulfide is expected to be compatible with surface-initiated HAT -RAFT.

[0125] Control Experiments. Drop Casting P'BiiA onto HDPE. P'BuA was synthesized using a previously described HAT -RAFT method. A dram vial equipped with a stir bar was charged with photocatalyst (1) (5.6 mg, 0.01 mmol, 0.5 equiv), disulfide (2) (11.1 mg, 0.02 mmol, 1.0 equiv), tert-butyl acrylate (586 pL, 5 mmol, 200 equiv), and dioxane (0.5 mL).The vial was sealed with a cap equipped with a Teflon septum. The reaction was degassed via 3 freeze-pump -thaw cycles and left under vacuum. The reaction was irradiated with a CFL at1 cm from the light source for 7 hours with air cooling. Aliquots were taken for1H NMR and GPC. Volatiles were removed in vacuo and the crude polymer was further purified by precipitation from hexanes. 'H NMR: 87% conversion, A / ntheo= 22.8 kg / mol. GPC: IGI>C= 21.5 kg / mol, D = 1.2. A 200 mg / mL solution of PlBuA in DCM was drop cast onto a 2 cm x2 cm piece of melt-pressed HDPE and allowed to air dry overnight. The film was then washed with di chloromethane and dried with air before taking an IR spectrum.

[0126] Thermal RAFT with HDPE. A 2-dram vial equipped with a stir bar was charged with AIBN (2 mg, 0.01 mmol, 0.60 equiv) 2-cyanopropan-2-yl benzodi thioate (5 mg, 0.02 mmol, 1.0 equiv), tert-butyl acrylate (0.7 mL, 5 mmol, 200 equiv), and dioxane (2.0 mL). A 1cm x 1cm piece of HDPE was submerged in the resulting solution, and the vial was sealed with a cap equipped with a Teflon septum. The reaction was degassed via 3 freeze-pump- thaw cycles and left under vacuum. The reaction was heated in a 70 °C oil bath for 4 hours before removing from heat and exposing to air. The HDPE was removed from the polymer solution, washed in DCM, and dried with air before recording an IR spectrum. IR spectra (FIG. 8) were obtained before and after the reaction.

[0127] Standard Conditions, no PE. Following the general procedure for surface- initiated HAT-RAFT, a solution of photocatalyst 1 (2.80 mg, 10.0 pmol, 1 equiv), disulfide 2 (5.55 mg, 10.0 pmol, 1 equiv), tert-butyl acrylate (293 pL, 2.0 mmol, 200 equiv), and dioxane (0.25 mL) was layered onto a glass microscope slide. The glass slide was covered with a second glass slide and irradiated for 18 hours, at which point was washed with DCM and dried with air to yield an unfunctionalized glass microscope slide. IR spectra (FIG. 9) were obtained before and after the reaction.

[0128] Standard Conditions, no light. Following the general procedure for surface- initiated HAT-RAFT, a solution of photocatalyst 1 (2.80 mg, 10.0 pmol, 1 equiv), disulfide 2 (5.55 mg, 10.0 pmol, 1 equiv), tert-butyl acrylate (293 pL, 2.0 mmol, 200 equiv), and dioxane (0.25 mL) was layered onto a melt-pressed HDPE film. The film sat in the dark for 18 hours, washed with DCM, and dried with air to yield an unfunctionalized HDPE film. IR spectra were obtained before and after the reaction, which show no change and no surface grafting.

[0129] Standard Conditions, no disulfide. Following the general procedure for surface- initiated HAT-RAFT, a solution of photocatalyst 1 (2.80 mg, 10.0 pmol, 1 equiv), tert-butyl acrylate (293 pL, 2.0 mmol, 200 equiv), and dioxane (0.25 mL) was layered onto a melt- pressed HDPE film and irradiated for 18 hours. The film was washed with DCM and driedwith air to yield a negligible amount of grafted P'BuA on the HDPE film. IR spectra were obtained before and after the reaction, which show almost no CO stretching peak, indicating negligible polymerization.

[0130] PET substrate. Following the general procedure for surface-initiated HAT¬RAFT, a solution of photocatalyst 1 (2.80 mg, 10.0 pmol, 1 equiv), disulfide 2 (5.55 mg, 10.0 pmol, 1 equiv), tert-butyl acrylate (293 pL, 2.0 mmol, 200 equiv), and dioxane (0.25 mL) was layered onto a PET film. The film was irradiated for 18 hours, washed with DCM, and dried with air to yield an unfunctionalized PET film. IR spectra (FIG. 10) were obtained before and after the reaction.

[0131] Synthesis of Brush Polymers for XPS and AFM Studies.

[0132] Preparation of LLI)PE-g-P'BiiA. In a nitrogen glovebox, photocatalyst 1 (2.80 mg, 10.0 pmol, 1 equiv), chain transfer agent 2 (5.55 mg, 10.0 pmol, 1 equiv), tert-butyl acrylate (293 pL, 2.0 mmol, 200 equiv), and dioxane (0.25 mL) were combined. The resulting solution was pipetted onto a silicon wafer spin-coated with linear low-density polyethylene (LLDPE), which was laid on a glass microscope slide. The LLDPE-coated wafer was covered with a second glass microscope slide and irradiated 1 cm away from a compact fluorescent lamp with a fan for cooling. Reaction proceeded for 18 hours, at which time the lamp was turned off and the wafer removed from the glovebox. The wafer was washed in di chloromethane for 2 min (min(s) = minute(s)) to prevent delamination of the LLDPE from the silicon wafer before drying with air. The LLDPE-g-P'B A wafer was characterized by XPS, profilometry, and AFM (FIGS. 11-14).

[0133] Preparation of LLDPE-g-PNaA. An LLDPE-g-P'BuA film was prepared as described above. After washing, the film was submerged overnight in a 0.5 M NaOH solution in 9: 1 DCM:MeOH. The resulting film was rinsed with water before drying with air. The LLDPE-g-PNaA wafer was characterized by AFM swelling studies (FIG. 17).

[0134] XPS Studies. Samples were analyzed using a Thermo Scientific Nexsa G2 Spectrometer with operating pressure ca. 1x10-9 Torr. Monochromatic Al Ka x rays (1486.6 eV) with photoelectrons collected from a 400 pm diameter analysis spot. Photoelectrons were collected at a 90° emission angle with source to analyzer angle of 54.7°. A hemispherical analyzer determined electron kinetic energy, using a pass energy of 200 eV for wide / survey scans, and 50 eV for high resolution scans. A flood gun was used for charge neutralization of non-conductive samples. XPS spectra (see, e.g., FIGS. 11-13) were obtained.

[0135] Brush Height Analysis.

[0136] Measuring Brush Height by AFM. LLDPE substrates were scratched with a razor blade, and step-height measurements were taken at the boundary between the scratched and unscratched regions. Brushes were then grown as described in preparation of LLDPE-g- P^BuA. The depth of the same scratch was measured after brush growth, and the difference between the two measurements is the reported brush height. AFM profiles and images (FIG. 14) were obtained.

[0137] Measuring Brush Height by Optical Profilometer. LLDPE substrates were scratched with a razor blade, and step-height measurements at 50x magnification were taken at the boundary between the scratched and unscratched regions. Brushes were then grown as described in preparation of LLDPE- -P'BuA. The depth of the same scratch was measured after brush growth by profilometry and atomic force microscopy, and the difference between the two measurements (before and after brush growth) is the reported brush height. For the same sample of LLDPE- -P'BuA, a brush height of 236 nm was measured by optical profilometry (FIG. 15) and a brush height of 260 nm was measured by AFM.

[0138] Measuring Brush Height by Stylus Profilometer. LLDPE substrates were scratched with a razor blade, and step-height measurements were taken at the boundary between the scratched and unscratched regions. Brushes were then grown as described in preparation of LLDPE- -P'BuA. The depth of the same scratch was measured after brush growth, and the difference between the two measurements is the reported brush height. The brush height measured using a stylus profilometer is 283 nm. Brush height measured by stylus profilometer is ~ 20-50 nm thicker than the values by AFM and optical profilometry.

[0139] Brush Height Analysis: Varying Film Thickness with Time.

[0140] Preparation ofLLDPE-g-PHuA. In a nitrogen glovebox, photocatalyst 1 (2.80 mg, 10.0 mol, 1 equiv), chain transfer agent 2 (5.55 mg, 10.0 mol, 1 equiv), tert-butyl acrylate (293 pL, 2.0 mmol, 200 equiv), and dioxane (0.25 mL) were combined. The resulting solution was pipetted onto a silicon wafer spin-coated with linear low-density polyethylene (LLDPE), which was laid on a glass microscope slide. The LLDPE-coated wafer was covered with a second glass microscope slide and irradiated 1 cm away from a compact fluorescent lamp with a fan for cooling. The reaction proceeded for 1 or 4 hours, at which time the lamp was turned off and the wafer removed from the glovebox. The wafer was washed in di chloromethane for 2 min before drying with air. Film thicknesses were assessed using optical profilometry. 1 Hour of Irradiation: brush height (measured byprofilometery) is 34 nm. 4 Hours of Irradiation: brush height (measured by profdometery) is 108 nm.

[0141] Brush Density Analysis. AFM Swelling Studies. The dry and wet thickness of brushes was measured through step-height measurements by AFM. To measure brush thickness, samples were scratched with a razor blade, and AFM height images were taken at the boundary between the scratched and unscratched regions. Imaging was conducted in tapping mode, and the thickness of each sample was measured in three different regions. To determine the swelling ratio, samples were incubated in pH 9 buffer solution for 10 minutes to equilibrate, and then the wet thickness of swollen brushes was measured.

[0142] LLDPE-g-PNaA, dry state (measured by AFM). Brush Height: 400 nm. Root mean square average roughness: 10.8 nm.

[0143] LLDPE-g-PNaA after 20 mins incubation in pH 9, wet state (measured by AFM). Brush Height: 650 nm. Root mean square average roughness: 20.5 nm.

[0144] Calculation of brush density from poly electrolyte scaling laws. The relationship between the swelling ratio of polyelectrolyte brushes and their density can be described by the equation, cr-0 97where L = swollen brush height, y = dry brush height, and o = brush density. This relationship is derived independently of degree of polymerization, indicating that molecular weight and dispersity of the brushes need not be known to calculate density. For LLDPE-g- PNaA brushes swollen in pH 9 buffer:L > 650 nmy 400 nm

[0145] Alexander-de Gannes Theory to Estimate Molecular Weight. Brush density is often related to brush height and Mn using the Alexander-de Gennes equation:Alexander-de Gannes theory can be used to estimate Mi of brushes with a known density and thickness. Using our 0.65 chains / nm2value calculated from swelling studies, the Mnof the LLDPE-g-PNaA brushes is ca. 250 kDa.

[0146] Manipulation of Brush Density. To probe whether the grafting density of brushes from PE is tunable in the SI HAT -RAFT system, we lowered the photocatalyst loading and performed a swelling study on the resulting brushes. Swelling studies were carried out as described above.

[0147] Preparation ofLLDPE-g-PNaA. Brushes were prepared as described in Synthesis of Brush Polymers for XPS and AFM Studies but with only 0.5 equivalents of photocatalyst 1 (1.40 mg, 5.0 pmol, 0.5 equiv). Brush height (dry and swollen) was determined by AFM (height difference of boundary between scratched and unscratched region). On a 316 nm LLDPE film, the dry brush height is 485 nm. On a 316 nm LLDPE film, the swollen brush height is 744 nm.

[0148] Calculation of brush density from poly electrolyte scaling laws.L 744 nm— = — - - = <ju y / y 485 nmThe grafting density obtained with a lower photocatalyst loading is comparable to the density obtained under standard conditions. Because there are a fixed number of CH2 groups available to initiate from on the surface as well as dioxane groups initiating polymerization in solution, it is challenging to vary the grafting density of SI HAT -RAFT from PE in a predictable way.

[0149] Kinetic Study of Static Water Contact Angle. In a nitrogen glovebox, onto a melt- pressed HDPE film was layered a solution of photocatalyst 1 (2.80 mg, 10.0 pmol, 1 equiv), disulfide 2 (5.55 mg, 10.0 pmol, 1 equiv), tert-butyl acrylate (293 pL, 2.0 mmol, 200 equiv), and dioxane (0.25 mL). The film was covered with a glass microscope slide and irradiated 1 cm away from a CFL for a predetermined amount of time, at which point it was removed from the glovebox, washed with DCM, and dried with air. After washing, the film was submerged overnight in a 0.5 M NaOH solution in 9: 1 DCM:MeOH. The resulting film was rinsed with water before drying with air. Contact angles were recorded for each film. Films were prepared which had been irradiated for 0, 1, 2, 3, 4, 5, 6, 7, 8, 10, and 12 hours (FIG. 16).

[0150] Synthesis of Brush Polymers with various Monomers.

[0151] Preparation of H DP E-g-P'BuA. The reaction of photocatalyst 1 (2.80 mg, 10.0 pmol, 1 equiv), disulfide 2 (5.55 mg, 10.0 pmol, 1 equiv), tert-butyl acrylate (293 pL, 2.0 mmol, 200 equiv), and dioxane (0.25 mL) layered onto a melt-pressed HDPE film affordedHDPE-g-P'BuA. The HDPE-g-P'BuA was characterized by IR spectroscopy and water contact angle: 0 = 86 ± 5°.

[0152] Preparation of HDPE-g-PNaA. A film of HDPE-g-P'BA was synthesized as above. After washing, the film was submerged overnight in a 0.5 M NaOH solution in 9: 1 DCM:MeOH. The resulting film was rinsed with water before drying with air. The HDPE-g- P'BA was characterized by IR spectroscopy and water contact angle: 0 = 63 ± 6°.

[0153] Preparation of EPDPE-gA^BuMA. The reaction of photocatalyst 1 (2.80 mg, 10.0 pmol, 1 equiv), disulfide 2 (5.55 mg, 10.0 pmol, 1 equiv), tert-butyl methacrylate (325 pL, 2.0 mmol, 200 equiv), and dioxane (0.25 mL) layered onto a melt-pressed HDPE film afforded HDPE-g-P'BuA. The HDPE-g- P'BuA was characterized by IR spectroscopy and water contact angle Water contact angle: 0 = 84 ± 5°.

[0154] Preparation of HDPE-g-PMA. The reaction of photocatalyst 1 (2.80 mg, 10.0 pmol, 1 equiv), disulfide 2 (5.55 mg, 10.0 pmol, 1 equiv), methyl acrylate (362 pL, 2.0 mmol, 200 equiv.), and dioxane (0.25 mL) layered onto a melt-pressed HDPE film afforded HDPE-g-PMA. The HDPE-g-PMA was characterized by IR spectroscopy and water contact angle: 0 = 86 ± 2°.

[0155] Preparation of HDPE-g-PMMA. The reaction of photocatalyst 1 (2.80 mg, 10.0 pmol, 1 equiv), disulfide 2 (5.55 mg, 10.0 pmol, 1 equiv), methyl methacrylate (426 pL, 2.0 mmol, 200 equiv), and dioxane (0.25 mL) layered onto a melt-pressed HDPE film afforded HDPE-g-PMMA. The HDPE-g-PMMA was characterized by IR spectroscopy and water contact angle: 0 = 85 ± 3°.

[0156] Preparation of HDPE-g-PAA. Photocatalyst 1 (2.80 mg, 10.0 pmol, 1 equiv), disulfide 2 (5.55 mg, 10.0 pmol, 1 equiv), acrylic acid (137 pL, 2.0 mmol, 200 equiv), water (0.125 mL), and dioxane (0.125 mL) were added to a one-dram vial. The reaction was sealed with a cap equipped with a Teflon septum, degassed via three freeze-pump-thaw cycles, and back-filled with nitrogen. The melt-pressed HDPE substrate was placed in a glass dish which was flushed with nitrogen. The contents of the dram vial were quickly pipetted over the HDPE substrate and the glass dish was covered. The substrate was irradiated by a compact fluorescent lamp placed 1 cm away from the lid of the glass dish with air cooling. After 18 hours, the lamp was turned off and the substrate removed from the glass dish. The substrate was washed in di chloromethane before drying with air. The HDPE-g-PAA was characterized by IR spectroscopy and water contact angle: 0 = 77 ± 5°.

[0157] Preparation of HDPE-g-PMAA. Photocatalyst 1 (2.80 mg, 10.0 pmol, 1 equiv), disulfide 2 (5.55 mg, 10.0 pmol, 1 equiv), methacrylic acid (169 pL, 2.0 mmol, 200 equiv), and dioxane (0.25 mL) were added to a one-dram vial. The reaction was sealed with a cap equipped with a Teflon septum, degassed via three freeze-pump-thaw cycles, and back-filled with nitrogen. The melt-pressed HDPE substrate was placed in a glass dish which was flushed with nitrogen. The contents of the dram vial were quickly pipetted over the HDPE substrate and the glass dish was covered. The substrate was irradiated by a compact fluorescent lamp placed 1 cm away from the lid of the glass dish with air cooling. After 18 hours, the lamp was turned off and the substrate removed from the glass dish. The substrate was washed in di chloromethane before drying with air. The HDPE-g-PMMA was characterized by IR spectroscopy and water contact angle: 0 = 77 ± 3°. Note: Although the IR spectrum of HDPE-g-PMAA shows only small amounts of functionalization, likely because MAA is a less active monomer towards radical polymerization, the dramatic decrease in water contact angle post-functionalization provides good evidence of the presence of brush polymer on the HDPE surface.

[0158] Preparation of HDPE-g-poly(sulfobetaine) . Photocatalyst 1 (2.80 mg, 10.0 pmol, 1 equiv), disulfide 2 (5.55 mg, 10.0 pmol, 1 equiv), 3-((2- (acryloyloxy)ethyl)dimethylammonio)propane-l -sulfonate (531 mg, 2.0 mmol, 200 equiv), water (0.25 mL) and dioxane (0.25 mL) were added to a one dram vial. The reaction was sealed with a cap equipped with a Teflon septum, degassed via three freeze-pump-thaw cycles, and back-filled with nitrogen. The melt-pressed HDPE substrate was placed in a glass dish which was flushed with nitrogen. The contents of the dram vial were quickly pipetted over the HDPE substrate and the glass dish was covered. The substrate was irradiated by a compact fluorescent lamp placed 1 cm away from the lid of the glass dish with air cooling. After 18 hours, the lamp was turned off and the substrate removed from the glass dish. The substrate was washed in water and acetone before drying with air. The HDPE-g- polyf sulfobetaine) was characterized by IR spectroscopy and water contact angle: 0 = 83 ± 3°.

[0159] Preparation of HDPE-g-Poly(PEG acrylate). Photocatalyst 1 (2.80 mg, 10.0 pmol, 1 equiv), disulfide 2 (5.55 mg, 10.0 pmol, 1 equiv), poly(ethylene glycol) methyl ether acrylate, i=480 g / mol (881 pL, 2.0 mmol, 200 equiv), and dioxane (0.25 mL) were added to a one dram vial. The reaction was sealed with a cap equipped with a Teflon septum, degassed via three freeze-pump-thaw cycles, and back-filled with nitrogen. The melt-pressedHDPE substrate was placed in a glass dish, which was flushed with nitrogen. The contents of the dram vial were quickly pipetted over the HDPE substrate and the glass dish was covered. The substrate was irradiated by a compact fluorescent lamp placed 1 cm away from the lid of the glass dish with air cooling. After 18 hours, the lamp was turned off and the substrate removed from the glass dish. The substrate was washed in water and acetone before drying with air. The HDPE-g- po / yfBEG acrylate was characterized by IR spectroscopy and water contact angle: 0 = 65 ± 5°.

[0160] Functionalization of Porous Polyethylene. Preparation of Teijen Membrane Hl)PE-g-P'BuA. The reaction of photocatalyst 1 (2.80 mg, 10.0 pmol, 1 equiv), disulfide 2 (5.55 mg, 10.0 pmol, 1 equiv), tert-butyl acrylate (293 pL, 2.0 mmol, 200 equiv), and dioxane (0.25 mL) layered onto a Teijen membrane HDPE film afforded HDPE-g-P'BuA. The HDPE-g-P'BuA was characterized by IR spectroscopy.

[0161] Tape Adhesion Test of Painted Substrates. The following protocol was completed 3 times. Using photocatalyst 1 (2.80 mg, 10.0 pmol, 1 equiv), disulfide 2 (5.55 mg, 10.0 pmol, 1 equiv), / / -butyl acrylate (290 pL, 2.0 mmol, 200 equiv), methyl methacrylate (210 pL, 2.0 mmol, 200 equiv), and dioxane (0.25 mL) layered onto a 3cm x 3cm melt-pressed HDPE film, an HDPE-g-[PMMA-co-PnBA] film was prepared according to the general procedure for surface-initiated HAT-RAFT.

[0162] Films were painted with Apple Barrel Matte Acrylic Paint and air dried for 24 hours. Scotch tape was applied to the brush polymer film and an unfunctionalized HDPE film and pressed down firmly. Pulling evenly and parallel to the film, the tape was peeled off. Photos were taken before and after to visually assess the amount of paint adhered. On the unfunctionalized HDPE surface, no paint remains adhered. On the functionalized surface, almost all of the paint remains adhered.

[0163] Lap Shear Testing. Using a procedure adapted from previous procedures, lap shear adhesion testing was carried out using a Shimadzu Autograph AGS-X tensile tester with a 5 kN load cell and a shear rate of 1.5 mm / min. Adhesive strength was evaluated by dividing the ultimate strength by the overlapped area, which was measured using digital calipers. Type of failure (adhesive, cohesive, or substrate) was evaluated visually.

[0164] LDPE films were melt pressed and molded with a stainless steel die into 3 cm x 8 cm x 1mm sheets as described above, functionalized on both sides with PMMA, and then cut into 1 cm x 1 cm films. Rectangular aluminum substrates were degreased prior to use by wiping off with an ethyl acetate soaked Kimwipe followed by an acetone soaked Kimwipe,and then air-dried. An LDPE or functionalized LDPE film was placed at the end of an aluminum substrate, and then covered with the end of a second aluminum substrate in an antiparallel manner. The substrates were held together with 2 small binder clips and placed in a 140 °C oven for 5 minutes before removing and allowing to slowly cool to room temperature.

[0165] Tensile tester clamps were aligned with a ruler. All LDPE samples failed adhesively while placing the sample in clamps, before any shear force was applied. For the LDPE-g-PMMA samples, shear force was applied at a rate of 1.5 mm / min until samples failed. 3 samples of each type were prepared and tested, and the values reported here are the average of 3 tests (FIG. 17).EXAMPLE 2

[0166] This example provides a description of polymer functionalized substrates of the present disclosure and methods of making same.

[0167] General Synthetic Protocol, Surface-Initiated Polymerization. In a nitrogen glovebox, photocatalyst (about 1 equiv.), chain transfer agent (about 1 equiv.), monomer (about 50-1000 equiv.), and solvent (about 0.04 M, which may be in chain transfer agent) are combined. The resulting solution is pipetted onto a flat polymer substrate which is laid on a glass microscope slide (e.g., FIG. 7). The substrate is covered with a second glass microscope slide and irradiated about 1 cm (cm = centimeter(s)) away from a compact fluorescent lamp with a fan for cooling. Reaction proceeds about for 16 hours, at which time the lamp is turned off and the substrate removed from the glovebox. The substrate is washed in solvent for about 2-30 minutes before drying with air.

[0168] Synthesis of HDPE- -P'B A (Scheme 3). In a nitrogen glovebox, photocatalyst 1 (2.80 mg, 10.0 pmol, 1 equiv.), chain transfer agent 2 (5.55 mg, 10.0 pmol, 1 equiv.), tertbutyl acrylate (293 pL, 2.0 mmol, 200 equiv.), and dioxane (0.25 mL, 0.04 M in chain transfer agent) were combined. The resulting solution was pipetted onto a high-density polyethylene (HDPE) film which was laid on a glass microscope slide (FIG. 7). The HDPE film was covered with a second glass microscope slide and irradiated 1 cm away from a compact fluorescent lamp with a fan for cooling. Reaction proceeded for 16 hours, at which time the lamp was turned off and the substrate removed from the glovebox. The substrate was washed in di chloromethane for 30 minutes before drying with air. FTIR: 2915 1 / cm (asymmetric C — H stretch), 2847 1 / cm (symmetric C — H stretch), 1727 1 / cm (C=O stretch), 1471 1 / cm (asymmetric C — H bend), 1461 1 / cm (symmetric C — H bend), 1366 1 / cm (CH3deformation), 1166 1 / cm (C — O stretch), 728 1 / cm (split CH2 rock), 718 1 / cm (split CH2 rock). Static water contact angle: ®avg=87.1° (-12° change from unfunctionalized HDPE (Gavg= 93°). XPS: XPS data supports the presence of polymer on the surface by atomic composition and shows the presence of 2 separate types of oxygen (singled bonded and double bonded to carbon.

[0169] Scheme 3. Functionalization of high-density polyethylene usinglBuMA.

[0170] Synthesis of HDPE-g-PMA. Same protocol as HDPE-g-P'BA with the following changes: photocatalyst 1 (2.80 mg, 10.0 pmol, 1 equiv.), chain transfer agent 2 (5.55 mg, 10.0 pmol, 1 equiv.), methyl acrylate (362 pL, 2.0 mmol, 200 equiv.), and dioxane (0.25 mL, 0.04 M in chain transfer agent). FTIR: 2915 1 / cm (asymmetric C — H stretch), 2847 1 / cm (symmetric C — H stretch), 1736 1 / cm (C=O stretch), 1471 1 / cm (asymmetric C — H bend), 1461 1 / cm (symmetric C — H bend), 1367 1 / cm (CH3 deformation), 1166 1 / cm (C — O stretch), 728 1 / cm (split CH2 rock), 718 1 / cm (split CH2 rock). Static water contact angle: 87° (-6° change from unfunctionalized HDPE).

[0171] Synthesis of HDPE-g-PMMA. Same protocol as HDPE-g-P'BA with the following changes: photocatalyst 1 (2.80 mg, 10.0 pmol, 1 equiv.), chain transfer agent 2 (5.55 mg, 10.0 pmol, 1 equiv.), methyl methacrylate (426 pL, 2.0 mmol, 200 equiv.), and dioxane (0.25 mL, 0.04 M in chain transfer agent). FTIR: 2915 1 / cm (asymmetric C — H stretch), 2847 1 / cm (symmetric C — H stretch), 1727 1 / cm (C=O stretch), 1471 1 / cm (asymmetric C — H bend), 1461 1 / cm (symmetric C — H bend), 1364 1 / cm (CH3 deformation), 1166 1 / cm (C — O stretch), 728 1 / cm (split CH2 rock), 718 1 / cm (split CH2 rock). Static water contact angle: 85° (-14° change from unfunctionalized HDPE).

[0172] Synthesis of HDPE-g-PNaA. A film of HDPE-g-P'BA was synthesized as above. After washing, the film was submerged overnight in a 0.5 M NaOH solution in 9: 1 DCM:MeOH. FTIR: 3400 1 / cm (O — H stretch), 2915 1 / cm (asymmetric C — H stretch), 2847 1 / cm (symmetric C — H stretch), 1727 1 / cm (C=O stretch), 1471 1 / cm (asymmetric C — H bend), 1461 1 / cm (symmetric C — H bend), 1166 1 / cm (C — O stretch), 728 1 / cm (split CEE rock), 718 1 / cm (split CEE rock). Static water contact angle: 63° (-35° change from unfunctionalized HDPE).

[0173] Synthesis of LLDPE-g-P'B A. In a nitrogen glovebox, photocatalyst 1 (2.80 mg,10.0 mol, 1 equiv.), chain transfer agent 2 (5.55 mg, 10.0 pmol, 1 equiv.), tert-butyl acrylate (293 pL, 2.0 mmol, 200 equiv.), and dioxane (0.25 mL, 0.04 M in chain transfer agent) were combined. The resulting solution was pipetted onto a silicon wafer spin-coated with linear low-density polyethylene (LLDPE) which was laid on a glass microscope slide. The LLDPE- coated wafer was covered with a second glass microscope slide and irradiated 1 cm away from a compact fluorescent lamp with a fan for cooling. Reaction proceeded for 16 hours, at which time the lamp was turned off and the wafer removed from the glovebox. The wafer was washed in di chloromethane for 2 min before drying with air. The LLDPE-g- PT3A wafer was characterized by XPS, profilometry, and AFM. XPS supports the presence of P'BA on the LLDPE layer. The P'BA brush layer is ca. 250 nm thick as observed by profilometry and AFM.

[0174] Synthesis of LLDPE-g-PNaA. LLDPE-g-P^BA was prepared as described above. After washing, the film was submerged overnight in a 0.5 M NaOH solution in 9: 1 DCM:MeOH.

[0175] AFM Swelling Studies of LLDPE-g-PNaA film: Dry brush thickness and brush thickness after incubation in pH 10 buffer solution were measured using AFM. Brushes swell from ca. 450 nm in thickness to ca. 600 nm in thickness (63% swelling), which matches other PNaA brush samples with grafting density, ca. 2 chains / nm2.

[0176] Alexander-De Gennes Estimates of Grafting Density: Grafting density of brush polymers made with using methods of the present disclosure can be estimated from dry brush height and theoretical number average molecular weight of the brush polymer layer using the Alexander-De Gennes equation:_ hpNA° Mnwhere o is the grafting density, h is the dry brush height, NA is Avogadro’s number, and AL is the number average molecular weight of the brush polymer layer. Estimating for a LLDPE-g-P'BA film with 260 nm dry brush height and an illlC0of 25 kDa, the grafting density is ca. 6 chains / nm2.

[0177] Substrates were functionalized using various monomers (Scheme 4). The functionalization was carried out using methods described in EXAMPLE 1. The functionalized substrates produced using the monomers of Scheme 4 were characterized by a static water contact angle (8) as described in EXAMPLE 1.

[0178] Scheme 4. Functionalization using various monomers.sulfobetaine zwitterion PEG derivative8 ® 83ae ® 65° a = standard conditions described in EXAMPLE 1.

[0179] Functionalization of substrates with polymer brushes of acrylic acid, methyl acrylate, tert-butyl acrylate, sodium acrylate, methyl methacrylate, methacrylic acid, tertbutyl methacrylate, sulfobetaine acrylate, tridecafluorooctyl acrylate, PEG-acrylate, and, 3- (trimethoxysilyl)propyl acrylate using monomers shown in Scheme 5 using the standard conditions described in EXAMPLE 1. Grafting was also shown using a sulfobetaine zwitterion monomer using the standard conditions described in EXAMPLE 1.

[0180] Scheme 5. Functionalization using various monomers.

[0181] Grafting (using the methods described in EXAMPLE 1) from high-density polyethylene, low-density polyethylene, linear low-density polyethylene, and isotactic polypropylene. See, e.g., FIGS 25, 26, and 31.

[0182] Grafting (using the methods described in EXAMPLE 1) was demonstrated using benzophenone derivative photocatalyst 1 as well as several thioxanthone derivatives (e.g., Schemes 6 and 7).

[0183] Scheme 6. Functionalization using various photocatalysts.The functionalized substrate products were characterized (as described in EXAMPLE 1) by IR spectroscopy (see, e.g., FIG. 18).

[0184] Scheme 7. Hydrogen atom transfer using a thioxanthone photocatalyst.

[0185] Chain transfer and photocatalyst turnover was demonstrated using turnover using2a and 2b:See, e g., FIGS. 2-5.

[0186] Disulfides showed desirable photocatalyst turnover activity. Polymerization in absence of the disulfide does not proceed as well (negligible polymerization was observed) by IR under standard conditions (Scheme 8 and FIG. 19). Polymerization in absence of the disulfide does not proceed as well by IR even with 5x the standard photocatalyst loading (FIG. 20).

[0187] Scheme 8. Polymerization in absence of the disulfide.

[0188] Other chemical oxidants, such as, for example, ferrocenium tetrafluoroborate(FC(BF4)), to turn over the photocatalyst do not work as well as the disulfide (Scheme 9 and FIG. 21).

[0189] Scheme 9. Use of ferrocenium tetrafluoroborate (Fc(BF4)), to turn over the photocatalyst.

[0190] Substrates that do not initiate polymerization. Certain evaluated substrates without hydridic C — H bonds do not initiate suitable polymerization: Mylar® (biaxially oriented polyethylene terephthalate) did not initiate polymerization (FIG. 22). Glass microscope slides (silicate glass) did not initiate polymerization (FIG. 23).

[0191] Certain evaluated hydrocarbon substrates, despite similar electronics to PE, do not initiate polymerization. Octadecane monolayer immobilized on a silicon substrate did not initiate polymerization. By X-ray photoelectron spectroscopy (XPS) (FIG. 24), the carbon scan is missing a diagnostic C=O peak characteristic of acrylate brushes.EXAMPLE 3

[0192] This example provides a description of a polymer functionalized substrate of the present disclosure and a method of making same.

[0193] Functionalization of polypropylene (shown in Scheme 25 below). It was shown by IR spectroscopy (FIG. 25) and an increase in mass that the surface of an isopolypropylene membrane was functionalized as described in EXAMPLE 2.

[0194] Scheme 10. Functionalization of polypropylene.EXAMPLE 4

[0195] This example provides a description of polymer functionalized substrates of the present disclosure and methods of making same and uses thereof.

[0196] Functionalization of isotactic polypropylene (iPP). iPP was functionalized as shown in Schemes 11 and 12. The functionalization was carried out using methods described in EXAMPLE 1.

[0197] Scheme 11. Functionalization of iPP using methyl methacrylate monomer.The iPP-g-PMA product was characterized (as described in EXAMPLE 1) by IR spectroscopy (FIG. 26) and exhibited a static water contact angle ( ) of 89 ° + / - 2 ° (iPP substrate exhibited a static water contact angle ( ) of 103 ° + / - 3 °).

[0198] Scheme 12. Functionalization of iPP using t-butyl methacrylate monomer.

[0199] iPP was functionalized using various thioxanthone photocatalysts shown in the following:where (i) 2, 2’ OMeThx: R1= R2= OMe, (ii) 2, 2’ pipThx: R1= R2= piperidine, and ITX: R1= R2= iPr. These photocatalysts showed increased functionalization of iPP compared tophotocatalysts.

[0200] Functionalization using zwitterionic monomer. A polyethylene substrate was functionalized as shown in Scheme 13. The functionalization was carried out using methods described in EXAMPLE 1.

[0201] Scheme 13. Functionalization of using zwittterionic monomer.The PE-g-poly(sulfobetaine acrylate) PSBA product was characterized (as described inEXAMPLE 1) by IR spectroscopy (FIG. 27) and exhibited a static water contact angle ( ) of 74 ° + / - 15 °.

[0202] Functionalization using TMPSA monomer. A high-density polyethylene substrate was functionalized as shown in Scheme 14. The functionalization was carried out using methods described in EXAMPLE 1.

[0203] Scheme 14. Functionalization using TMPSA monomer.The HDPE-g-P(trimethoxypropyl acrylate) product was characterized (as described in EXAMPLE 1) by IR spectroscopy (FIG. 28).

[0204] Functionalization using fluorinated monomer. A polyethylene substrate was functionalized as shown in Scheme 15. The functionalization was carried out using methods described in EXAMPLE 1.

[0205] Scheme 15. Functionalization using fluorinated monomer.The HDPE-g-P(tridecafluorooctyl acrylate) product was characterized (as described in EXAMPLE 1) by IR spectroscopy (FIG. 29).

[0206] Functionalization of a PE / iPP copolymer substrate. A PE / iPP copolymer substrate was functionalized as shown in Scheme 16. The functionalization was carried out using methods described in EXAMPLE 1.

[0207] Scheme 16. Functionalization of a PE / iPP copolymer (Dow INTUNE D5545) substrate.The PE / iPP-g-PMA product was characterized (as described in EXAMPLE 1) by IR spectroscopy (FIG. 30) and exhibited a static water contact angle ( ) of 90 ° + / - 3 ° (for the la photocatalyst) and 83 ° + / - 3 ° (for the lb photocatalyst).

[0208] Functionalization of commercial PE substrates. Commercial PE substrates were functionalized with tBuMA. The functionalization was carried out using methods described in EXAMPLE 1. The PE / PlBuA products (LDPE plastic wrap and HDPE plastic jug were characterized (as described in EXAMPLE 1) by IR spectroscopy (FIGS. 31 and 32).

[0209] Functionalization of polyamide and polyether substrates. Polyamide and poly ether substrates were functionalized tBuMA. The functionalization was carried out using methods described in EXAMPLE 1. The polyamide product (Nylon 6,6-g-PtBuA) and poly ether product (iPPO-g-PtBuA) were characterized (as described in EXAMPLE 1) by IR spectroscopy (FIGS. 33 and 34).

[0210] Although the present disclosure has been described with respect to one or more particular example(s), it will be understood that other examples of the present disclosure may be made without departing from the scope of the present disclosure.

Claims

CLAIMS:

1. A polymer functionalized substrate comprising: a substrate comprising a polymer; and a plurality of polymer groups, wherein the polymer groups are independently at each occurrence covalently bound to at least a portion of a surface or all surfaces of the polymer of the substrate.

2. The polymer functionalized substrate of claim 1, wherein the substrate is a polymer or comprises an exterior polymer layer.

3. The polymer functionalized substrate of claim 1, wherein the polymer comprises a polyolefin, a polystyrene, a polyether, a polyamide, or a structural analog thereof, a copolymer thereof, or a combination thereof.

4. The polymer functionalized substrate of claim 3, wherein the polyolefin is chosen from polyethylene, polypropylene, polystyrene, structural analogs thereof, copolymers thereof, and any combination thereof.

5. The polymer functionalized substrate of claim 4, wherein the polyethylene is chosen from high-density polyethylene, low-density polyethylene, linear high-density polyethylene, linear low-density polyethylene, structural analogs thereof, copolymers thereof, and any combination thereof.

6. The polymer functionalized substrate of claim 1, wherein the polymer groups are chosen from polyacrylate groups, polymethacrylate groups, polyacrylamide groups, polymethacrylamide groups, polyvinyl acetate groups, polymaleic anhydride groups, polymaleimide groups, polyolefin groups, polymer groups comprising one or more PEG group(s), zwitterionic polymer groups, structural analogs thereof, and copolymers thereof, and any combination thereof.

7. The polymer functionalized substrate of claim 1, wherein the functionalized substrate comprises about 0.05 chains / nm2to about 6 chains / nm28. The polymer functionalized substrate of claim 1, wherein the polymer groups independently at each occurrence comprise a dimension substantially normal or normal to a plane defining a surface of the substrate of about 10 nm to about 1000 nm.

9. The polymer functionalized substrate of claim 1, wherein at least a portion, substantially all, or all the polymer groups form a predetermined pattern on at least a portion, substantially all, or all of a surface or all the surfaces of the substrate.

10. A method of making a polymer functionalized substrate comprising: contacting a substrate comprising a polymer with one or more monomer(s), one or more photocatalyst(s), one or more chain transfer agent(s), and optionally, one or more solvent(s); and irradiating at least a portion, substantially all, or all of a surface or the surfaces of the substrate with electromagnetic radiation, wherein the polymer functionalized substrate is formed.

11. The method of claim 10, wherein the monomer(s) is / are chosen from acrylates, methacrylates, acrylamides, methacrylamides, vinyl acetates, maleic anhydrides, maleimides, olefins, monomers comprising one or more zwitterionic group(s), monomers comprising one or more PEG group(s), structural analogs thereof, and any combination thereof.

12. The method of claim 10, wherein the monomer(s) is / are present at about a concentration of about 1 M to about 7 M.

13. The method of claim 10, wherein the photocatalysts(s) is / are chosen from aromatic ketones, thioxanthones, xanthene dyes, polyoxometalates, uranyl salts, tungsten anions, metal-oxo porphyrins, tris(amino)cyclopropenium radical dications, structural analogs thereof, and any combination thereof.

14. The method of claim 10, wherein at least a portion or all the photocatalysts(s) comprise(s) the following structure:structural analog thereof, wherein x is independently at each occurrence 0, 1, 2, or 3, andR1group(s) and R2(groups) are independently at each occurrence chosen from -H, -OH, alkoxy groups, alkylamine groups, aryl groups, thiol groups, thioether groups, halide groups, fluorinated alkyl groups, and any combinations thereof.

15. The method of claim 10, wherein the photocatalyst(s) is / are present at a concentration of about 10 mM to about 80 mM.

16. The method of claim 10, wherein the chain transfer agent(s) is / are chosen from disulfide derivates of trithiocarb onates, dithiocarbonates, diothiocarbamates, xanthanates, and any combination thereof.

17. The method of claim 10, wherein at least a portion or all the chain transfer agent(s) the following structure:structural analog thereof, whereinR3is independently at each occurrence chosen from alkyl groups, aryl groups, -SR3groups, - OR3groups, -N(R3)2groups, wherein R3is independently at each occurrence an alkyl group or an aryl group, structural analogs thereof, and any combinations thereof.

18. The method of claim 10, wherein the chain transfer agent(s) is / are present at a concentration of about 10 mM to about 80 mM.

19. The method of claim 10, wherein the electromagnetic radiation comprises one or more wavelength(s) of about 200 nm to about 700 nm.

20. The method of claim 10, wherein the irradiating at least a portion, substantially all, or all of a surface or the surfaces of the substrate with the electromagnetic radiation is carried out in predetermined pattern.

21. The method of claim 10, wherein the solvent(s) is / are chosen from ethers, water, fluoroalkanes, and any combination thereof.

22. The method of claim 10, wherein the contacting and / or irradiating is / are repeated a desired number of times.

23. An article of manufacture comprising one or more polymer functionalized substrate(s) of claim 1.

24. The article of manufacture of claim 23, wherein the article of manufacture is chosen from biomedical devices, marine articles, automotive articles, consumables, containers, trays, and membranes.

25. The article of manufacture of claim 23, wherein the polymer functionalized substrate(s) exhibit(s) one or more or all of the following:• desirable friction;• antifouling behavior;• antimicrobial behavior;• desirable wettability;• hydrophobic behavior;• chemoselectivity; or• scratch / abrasion resistance.

Images