Hyperbranched polymers for curable high refractive index compositions, articles thereof, and methods of making such articles

Abstract

Described herein is a curable composition derived from (i) a hyperbranched polymer comprising a plurality of first terminal carbon-carbon double bonds, wherein the hyperbranched polymer comprises a reaction product of components: (a) at least one unsaturated compound consisting of C, H, and optionally Si atoms, O atoms, or Si and O atoms, and having p second terminal carbon-carbon double bonds, wherein each p is independently an integer greater than or equal to 2; (b) at least one organosilane compound consisting of C,H, Si, and optionally O atoms and having q Si-H groups, wherein each q is independently an integer greater than or equal to 2; and (c) at least one hydrosilylation reaction catalyst, wherein p / q is at least 2.1; and (ii) at least one multifunctional thiol comprising at least 2 thiol groups. These curable compositions when cured have a refractive index of at least 1.610 (when measured at 450nm).

Description

HYPERBRANCHED POLYMERS FOR CURABLE HIGH REFRACTIVE INDEX COMPOSITIONS, ARTICLES THEREOF, AND METHODS OF MAKING SUCH ARTICLES TECHNICAL FIELD

[0001] Disclosed herein are unsaturated hyperbranched polymers reacted in a thiol-ene reaction to achieve compositions having a high refractive index. Curable compositions and articles using such compositions in, for example, optical devices, are disclosed. SUMMARY

[0002] In the display industry, a series of alternating organic and inorganic layers (referred to as thin film encapsulation, TFE) may be used on top of an optical display such as an organic light emitting device (OLED) or quantum dot display, to protect the underlying display and enhance the performance and lifetime of the display.

[0003] In thin film encapsulation, the function of the inorganic layers is to block the ingress of air and moisture into the underlying optical device. The functions of the organic layers are twofold: 1) to planarize the substrate and present a smooth interface for the deposition of the inorganic layer; and 2) to decouple any defects (pinholes, micro-cracks) that may occur in the inorganic layers on either side of the organic layer. The organic layer can be thought of as a buffer layer that is critical for the success of the inorganic layer barrier function.

[0004] There is a desire to identify curable organic compositions with low viscosities that could be ink jet printable and result in an organic layer having a high refractive index.

[0005] In one aspect, a curable composition is described comprising: (i) a hyperbranched polymer comprising a plurality of first terminal carbon-carbon double bonds, wherein the hyperbranched polymer comprises a reaction product of components: (a) at least one unsaturated compound consisting of C, H, and optionally Si atoms, O atoms, or Si and O atoms, and having p second terminal carbon-carbon double bonds, wherein each p is independently an integer greater than or equal to 2; (b) at least one organosilane compound consisting of C, H, Si, and optionally, O atoms and having q Si-H groups, wherein each q is independently an integer greater than or equal to 2; and (c) at least one hydrosilylation reaction catalyst, wherein p / q is at least 2.1; and (ii) at least one multifunctional thiol comprising at least 2 thiol groups; and wherein the curable composition is substantially free of solvent.

[0006] In another aspect, an article is disclosed. The article comprises a substrate with a first major surface and a second major surface; a cured organic layer adjacent to at least a portion of the second major surface of the substrate, wherein the cured organic layer is derived from (i) a hyperbranched polymer comprising a plurality offirst terminal carbon-carbon double bonds, wherein the hyperbranched polymer comprises a reaction product of components: (a) at least one unsaturated compound consisting of C, H, and optionally Si atoms, O atoms, or Si and O atoms, and having p second terminal carbon-carbon double bonds, wherein each p is independently an integer greater than or equal to 2; (b) at least one organosilane compound consisting of C, H, Si, and optionally O atoms and having q Si-H groups, wherein each q is independently an integer greater than or equal to 2; and (c) at least one hydrosilylation reaction catalyst, wherein p / q is at least 2.1; and (ii) at least one multifunctional thiol comprising at least 2 thiol groups; and an inorganic barrier layer in contact with the cured organic layer, wherein the cured organic layer has a refractive index of at least 1.610 (measured at 450 nm).

[0007] In yet another aspect, a method of preparing an article is described. The method comprising: providing a substrate with a first major surface and a second major surface; providing a curable composition comprising: (i) a hyperbranched polymer comprising a plurality of first terminal carbon-carbon double bonds, wherein the hyperbranched polymer comprises a reaction product of components: (a) at least one unsaturated compound consisting of C, H, and optionally Si atoms, O atoms, or Si and O atoms, and having p second terminal carbon-carbon double bonds, wherein each p is independently an integer greater than or equal to 2; (b) at least one organosilane compound consisting of C, H, Si, and optionally O atoms and having q Si-H groups, wherein each q is independently an integer greater than or equal to 2; and (c) at least one hydrosilylation reaction catalyst, wherein p / q is at least 2.1; and (ii) at least one multifunctional thiol comprising at least 2 thiol groups; disposing the curable composition on at least a portion of the second major surface of the substrate to form a curable layer; curing the curable layer to form a cured organic layer, wherein the cured organic layer has a refractive index of at least 1.610 measured at 450 nm; and depositing an inorganic barrier layer on the cured organic layer.

[0008] The above summary is not intended to describe each embodiment. The details of one or more embodiments of the invention are also set forth in the description below. Other features, objects, and advantages will be apparent from the description and from the claims. BRIEF DESCRIPTION OF DRAWINGS

[0009] The present application may be more completely understood in consideration of the following detailed description of various embodiments of the disclosure in connection with the accompanying drawings.

[0010] Figure 1 shows a cross sectional view of an embodiment of an article of this disclosure.

[0011] Figure 2 shows a cross-sectional view of an embodiment of another article of this disclosure.

[0012] In the following description of the illustrated embodiments, reference is made to the accompanying drawings, in which is shown by way of illustration, various embodiments in which the disclosure may be practiced. It is to be understood that the embodiments may be utilized and structural changes may be made without departing from the scope of the present disclosure. The figures are not necessarily to scale. Like numbers used in the figures refer to like components. However, it will be understood that the use of a number to refer to a component in a given figure is not intended to limit the component in another figure labeled with the same number. DETAILED DESCRIPTION

[0013] As used herein, the term “a”, “an”, and “the” are used interchangeably and mean one or more; and “and / or” is used to indicate one or both stated cases may occur, for example A and / or B includes, (A and B) and (A or B).

[0014] Also herein, recitation of ranges by endpoints includes all numbers subsumed within that range (e.g., 1 to 10 includes 1.4, 1.9, 2.33, 5.75, 9.98, etc.).

[0015] Also herein, recitation of “at least one” includes all numbers of one and greater (e.g., at least 2, at least 4, at least 6, at least 8, at least 10, at least 25, at least 50, at least 100, etc.).

[0016] The terms “room temperature” and “ambient temperature” are used interchangeably and have their conventional meaning, referring to temperatures of from 20-25°C.

[0017] As used herein, the term “adjacent” refers to two layers that are proximate to another layer. Layers that are adjacent may be in direct contact with each other, or there may be an intervening layer. There is no empty space between layers that are adjacent.

[0018] As used herein, “comprises at least one of” A, B, and C refers to element A by itself, element B by itself, element C by itself, A and B, A and C, B and C, and a combination of all three.

[0019] In the present disclosure, it has been found that a curable composition comprising an unsaturated hyperbranched polymer and a multifunctional thiol can result in cured compositions having a high index of refraction and, optionally, a high glass transition temperature (Tg).

[0020] The curable compositions of the present disclosure are substantially free of solvent and comprise at least one multifunctional thiol and a hyperbranched polymer comprising a plurality of first terminal C- C double bonds (or -ene groups).

[0021] Hyperbranched polymers according to the present disclosure can be prepared by a hydrosilylation reaction of a carbon-carbon double bond from an unsaturated compound with a Si-H bond from an organosilane compound facilitated by at least one hydrosilylation catalyst.

[0022] Useful unsaturated compounds consist of C, H, and optionally Si and / or O atoms and may independently have p second terminal carbon-carbon double bond groups. In some embodiments, usefulunsaturated compounds have from 4 to 50 carbon atoms (e.g., 4 to 50, 4 to 36, 4 to 18, or 4 to 12 carbon atoms), 0 to 10 silicon atoms (e.g., 0 to 10, 1 to 10, 0 to 6, 1 to 6, 2 to 10, 2 to 6, or 2 to 4 silicon atoms), and 0 to 9 oxygen atoms (e.g., 0 to 9, 0 to 6, 0 to 4, 0 to 2, or 0 to 1 oxygen atom). If Si is present, it is preferably not to have Si-H functional groups as it could cause self-reaction. If O is present, it is preferably in an ether linkage (i.e., C-O-C). Each p is independently an integer greater than or equal to 2 (e.g., 3, 4, 5, 6, 7, or 8). In some embodiments, useful unsaturated compounds consist of C, and H atoms. In some embodiments, useful unsaturated compounds consist of C, H, and Si atoms. In some embodiments, useful unsaturated compounds consist of C, H, and O atoms. In some embodiments, useful unsaturated compounds consist of C, H, Si, and O atoms. In some embodiments, useful unsaturated compounds include aromatic carbon atoms, while in other embodiments they do not.

[0023] In some embodiments, a useful unsaturated compound comprises at least one silicon atom such as represented by the formula Si(OSiR22CH=CH2)b(R2CH=CH2)c(R1)dEach R2is independently a direct bond (i.e., a covalent bond) or a hydrocarbylene group having 1 to 12carbon atoms, and optionally comprising at least one ether linkage. Examples include methylene,ethylene, propane-1,3-diyl, propane-1,2-diyl, butane-1,4-diyl, butane-1,3-diyl, pentane-1,5-diyl, pentane-1,4-diyl, hexane-1,6-diyl, octan-1,8-diyl, decan-1,10-diyl,dodecan-1,12-diyl, 1,4-phenylene, and 1,8-biphenylene. Each R1is independently a hydrocarbyl group having from 1 to 12 carbon atoms (e.g., methyl, ethyl, n- propyl, isopropyl, n-butyl, sec-butyl, n-pentyl, n-hexyl, phenyl, biphenylyl, and alkyl-substituted phenyl),and optionally comprising at least one ether linkage. In some embodiments, R1comprises an optionallysubstituted phenyl group (e.g., phenyl, biphenylyl, tolyl, xylyl, methoxyphenyl). b is an integer from 0 to 4 (i.e., 0, 1, 2, 3, or 4), c is an integer from 0 to 4 (i.e., 0, 1, 2, 3, or 4), and d is an integer from 0 to 2 (i.e., 0, 1, or 2), with the proviso that b + c ≥ 2 (in some embodiments, b + c ≥ 3)and b + c + d = 4.

[0024] Exemplary unsaturated silicon-containing compounds include: 1,3-divinyl-1,3-diphenyl-1,3- dimethyldisiloxane; 1,1,3,3-tetraphenyl-1,3-divinyldisiloxane; 1,4-bis(vinyldimethylsilyl)benzene; 1,5- divinyl-3-phenylpentamethyltrisiloxane; 1,3-divinyl-1,1,3,3,-tetramethyldisiloxane; 1,4-divinyl-1,1,4,4- tetramethyl-1,4-disilabutane; divinyldimethylsilane; 1,5-divinyl-3,3-diphenyl-1,1,5,5- tetramethyltrisiloxane; 1,3-divinyltetrakis(trimethylsiloxy)disiloxane; 1,5-divinylhexamethyltrisiloxane; bis(divinyl)-terminated polydimethylsiloxane; 1,3-divinyltetraethoxydisiloxane; 1,3-divinyl-1,3- dimethyl-1,3-dimethoxydisiloxane; trivinylmethoxysilane; 1,3,5-trivinyl-1,3,5-trimethylcyclotrisiloxane; 1,3,5-trivinyl-1,1,3,5,5-pentamethyltrisiloxane; 1,3,5,7-tetravinyl-1,3,5,7-tetramethylcyclotetrasiloxane; 1,1,3,3-tetravinyldimethyldisiloxane; tetravinylsilane; tetraallylsilane; 1,3,5,7,9-pentavinyl-1,3,5,7,9- pentamethylcyclopentasiloxane; hexavinyldisiloxane; and 1,3,5,7,9,11-hexavinylhexamethyl- cyclohexasiloxane. The foregoing vinyl compounds are available from commercial suppliers such as, for example, Gelest, Inc., Morrisville, Pennsylvania, and / or can be synthesized by known methods. Of thesetetravinylsilane, tetraallylsilane, and 1,1,3,3-tetraphenyl-1,3-divinyldisiloxane are preferred in some embodiments.

[0025] In some embodiments, useful unsaturated compound(s) do not comprise silicon, but are hydrocarbons, consisting of C and H atoms. The hydrocarbons may be aromatic or aliphatic. The hydrocarbons may be cyclic, linear, or branched in nature. The hydrocarbons preferably have at least 3, 4, 6, or even more vinyl or allyl groups. Such exemplary unsaturated compounds include trivinycyclohexane.

[0026] Useful organosilane compounds that are reacted with the unsaturated compound(s) described above may independently have q Si-H groups and consist of C,H, Si, and optionally O atoms. In some embodiments, useful organosilane compounds have from 4 to 50 carbon atoms (e.g., 4 to 50, 4 to 36, 4 to 18, or 4 to 12 carbon atoms), 2 to 10 silicon atoms (e.g., 2 to 10, 2 to 6, or 2 to 4 silicon atoms), and 0 to 9 oxygen atoms (e.g., 0 to 9, 0 to 6, 0 to 4, 0 to 2, or 0 to 1 oxygen atom). If O is present, Z, as shown in the equation below, is preferably a single oxygen atom or the oxygen is present in an ether linkage. Each q is independently an integer greater than or equal to 2 (e.g., 3, 4, 5, 6, 7, or 8). In some embodiments, useful organosilane compounds consist of C, H, and Si atoms. In some embodiments, useful organosilane compounds include aromatic carbon atoms, while in other embodiments they do not.

[0027] In some embodiments, useful organosilane compound(s) is / are independently represented by the formula Z(SiR12H)aEach Z is independently an a-valent radical composed of Si and O, or Z is an a-valent radical composed of C, H, and optionally O.

[0028] Each Z independently has from 1 to 12 carbon atoms. For example, Z may be a carbon atom (tetravalent), an oxygen atom (divalent), methylene (divalent), ethan-1,2-diyl (divalent), propan-1,3-diyl(divalent), CH3CH3(CH2-)3(trivalent). In some embodiments Z is a phenylene group.

[0029] as defined previously hereinabove.

[0030] a is an integer from 2 to 8 (i.e., 2, 3, 4, 5, 6, 7, or 8).

[0031] Exemplary organosilane compounds include: 1,1,4,4-tetramethyl-1,4-disilabutane; 1,4- bis(dimethylsilyl)benzene; 1,2-bis(dimethylsilyl)benzene; tris(dimethylsiloxy)phenylsilane; 1,1,3,3- tetramethyldisiloxane; 1,3-disilapropane; bis[(p-dimethylsilyl)phenyl] ether; 1,3,5,7,9- pentamethylcyclopentasiloxane; 1,1,3,3,5,5-hexamethyltrisiloxane; 1,3,5,7-tetramethylcyclotetrasiloxane; 1,3-diphenyltetrakis(dimethylsiloxy)disiloxane; tris(dimethylsiloxy)ethoxysilane; methyltris(dimethylsiloxy)silane; 1,1,1,3,3,5,5-heptamethyltrisiloxane; 1,1,3,3-tetraisopropyldisiloxane; 4,4'-bis(dimethylsilyl)biphenyl; and tetrakis(dimethylsiloxy)silane. The foregoing Si-H group-containing compounds are available from commercial suppliers such as, for example, Gelest, Inc. and / or can be synthesized by known methods. Of these, 1,1,4,4-tetramethyl-1,4-disilabutane, 1,4- bis(dimethylsilyl)benzene, bis[(p-dimethylsilyl)phenyl]ether, tetrakis(dimethylsiloxy)silane are preferred in some embodiments.

[0032] Hydrosilylation, also called catalytic hydrosilylation, describes the addition of Si-H bonds across unsaturated bonds. When hydrosilylation is used to synthesize hyperbranched polymers according to the present disclosure, carbon-carbon double bond(s) on the unsaturated compound react with Si-H group(s) on the organosilane compounds. The stoichiometry of the reactants is adjusted such that there is at least a 2.1 equivalent excess of carbon-carbon double bonds relative to Si-H groups; that is, p / q is at least 2.1. This ensures that the hyperbranched polymer will have pendant carbon-carbon double bonds, and helps limit unwanted crosslinking of the polymer during its synthesis. In some embodiments the ratio p / q is at least 2.1, 2.5, 3, 3.1, 3.5, 4, 4.5, or even at least 5.

[0033] The hydrosilylation reaction is typically catalyzed by a platinum catalyst, and generally heat is applied to the reaction. In this reaction, which is known in the art, the Si-H adds across the double bond to form new C-H and Si-C bonds.

[0034] Useful hydrosilylation catalysts may include thermal catalysts and / or photocatalysts. Exemplarythermal catalysts include platinum and rhodium complexes such as H2PtCl6(Speier's catalyst);organometallic platinum complexes such as, for example, a coordination complex of platinum and a divinyldisloxane (Karstedt's catalyst); and chloridotris(triphenylphosphine)rhodium(I) (Wilkinson's catalyst).

[0035] Useful platinum photocatalysts are disclosed, for example, in U.S. Pat. No.7,192,795 (Boardman et al.) and references cited therein. Exemplary platinum photocatalysts are selected from the group consisting of Pt(II) β-diketonate complexes (such as those disclosed in U.S. Pat. No.5,145,886 (Oxman et al.)), (η5-cyclopentadienyl)tri(σ-aliphatic)platinum complexes (such as those disclosed in U.S. Pat. No.4,916,169 (Boardman et al.) and U.S. Pat. No. 4,510,094 (Drahnak)), and C7-20-aromatic substituted(η5-cyclopentadienyl)tri(σ-aliphatic)platinum complexes (such as those disclosed in U.S. Pat. No. 6,150,546 (Butts)). Hydrosilylation photocatalysts are activated by exposure to actinic radiation, typically ultraviolet light, for example, according to known methods.

[0036] The amount of hydrosilylation catalyst may be any effective amount. In some embodiments, the amount of hydrosilylation catalyst is in an amount of from about 0.5 to about 30 parts of platinum per million parts of the total weight of Si-H and carbon-carbon double bond groups, although greater and lesser amounts may also be used.

[0037] To make the hyperbranched polymer, the unsaturated compound and organosilane compound are combined with the hydrosilylation catalyst under conditions such that hydrosilylation occurs. In some cases, mere mixing is sufficient. In other cases, heating and / or irradiation with ultraviolet light may be helpful.

[0038] In some embodiments, the hyperbranched polymer according to the present disclosure has a molecular weight of at least 1000, 1500 or even 2000 g / mol. In some embodiments, the hyperbranched polymer according to the present disclosure has a molecular weight of at most 5000, 4000, 3500, or even 3000 g / mol.

[0039] The hyperbranched polymer of the present disclosure comprises a plurality of terminal unsaturation sites, wherein the unsaturation sites are a C-C double bond (-ene). The hyperbranched polymers of the present disclosure comprise at least 2 terminal unsaturation sites, more preferably at least 3 or even at least 4 terminal unsaturation sites. Typically, the hyperbranched polymers of the present disclosure comprise no more than 10, 15, or even 20 terminal unsaturation sites.

[0040] Hyperbranched polymers according to the present disclosure are useful, for example, for preparing curable compositions. The curable compositions comprise the hyperbranched polymer and a multifunctional thiol.

[0041] The multifunctional thiols of the present disclosure comprise at least two thiol (i.e., -SH) groups, although they may have more than 2 thiol groups, for example 3, 4, or even 5 thiol groups. The multifunctional thiols of the present disclosure either comprise an aromatic group or are a non-aromatic thiol. In some embodiments, the multifunctional thiols are liquids at ambient conditions, in other words, room temperature and 1 atmosphere. In some embodiments, the multifunctional thiols of the present disclosure have a melting point onset below 80, 70, 60, 50, 40, or even 30°C at ambient pressure (e.g., 760 mm Hg).

[0042] In some embodiments, the multifunctional thiol is a non-aromatic thiol, which has a liquid refractive index of at least 1.620, 1.625, 1.630, 1.635, 1.640, 1.650, 1.655, or even 1.660 as determined with a white light refractometer. Generally, the refractive indices of the non-aromatic multifunctional thiols do not go above 1.71 or even 1.70. Exemplary non-aromatic multifunctional thiols, which may have refractive indices of at least 1.620 include: 2,3-bis-2-mercaptoethylthio-1-propanethiol, 4- mercaptomethyl-1,8-dimercapt-3,6-dithiaoctane; 5,7-dimercaptomethyl-1,11-dimercapto-3,6, 9- trithiaundecane; 4, 8-dimercaptomethyl-1, 11-dimercapto-3,6,9-trithiaundecane; and 4,7- dimercaptomethyl-1,11-dimercapto-3,6,9-trithiaundecane. Other non-aromatic multifunctional thiols include: poly(ethylene glycol) dithiol; 1,2,3-trimercaptopropane; 2,3-bis-2-mercaptoethylthio-1- propanethiol; 1,2-ethanedithiol; 2,2'-thiodiethanethiol; bi(mercaptoethyl)sulfide; 2,5- bis(mercaptomethyl)-1,4-dithiane; tetra(ethylene glycol) dithiol; 2,2’-(ethylenedioxy)diethanethiol; pentaerythritol terakis(3-mercaptopropionate; trimethylolpropane tris(3-mercaptopropionate; thenon-aromatic multifunctional thiols may be used in addition to non-aromatic multifunctional thiols having a refractive index of at least 1.620 and / or aromatic multifunctional thiols to assist with solubilityof the components in the curable composition. However, care should be taken to minimize the amount of these lower refractive index materials so as to maintain the high refractive index of the finished product.

[0043] In some embodiments, the multifunctional thiol is an aromatic thiol. Aromatic thiols can have high refractive indices, helping to generate a cured composition having a high refractive index. Exemplary aromatic multifunctional thiols include: 1,3-benzenedithiol; toluenedithiol, 1,3- benzenedimethanethiol; 1,3,4-thiadiazole-2.5-dithiol, (1,24) thiadiazole-3,5-dithiol, 1,3,5- trimercaptobenzene, 2-thiazoline-2-thiol, 1,1’,4’,1”-terphenyl-4-thiol, 5-bromopyridine-2-thiol, biphenyl- 4-thiol, 1,7-napthalenedithiol, and 1,5-napthalenedithiol.

[0044] In some embodiments, a low molecular weight, unsaturated compound comprising at least 2 or more terminal unsaturated groups is added to the curable composition. Such low molecular weight compounds comprise at least 2, 3, 4, or even 5 terminal unsaturated groups. Terminal unsaturated groups include carbon-carbon double bonds (i.e., -ene groups) or carbon-carbon triple bonds (i.e., -yne groups). In some embodiments, these low molecular weight compounds have a molecular weight of less than 800, 700, 600, 500, or even 400 g / mol.

[0045] The hyperbranched polymers, multifunctional thiols and optional low molecular weight unsaturated compounds described above react in a so-called thiol-ene reaction. Typically, the hyperbranched polymers, multifunctional thiols, and optional low molecular weight unsaturated compounds are reacted using sufficient amounts to ensure an absence of reactive groups remaining in the cured product. A terminal double bond reacts with one thiol, whereas a terminal alkyne reacts with 2 thiols. Thus, ideally, there should be a mole ratio of terminal double bonds in the hyperbranched polymer to thiol groups in the multifunctional thiol compound of 1:1, and in the case of the triple bonds, which may be present in the optional low molecular weight unsaturated compound, there should be a mole ratio of a terminal alkyne bond to thiol group of 1:2. In some embodiments, the mole ratio of terminal C-C double bonds in the hyperbranched polymer (and optional low molecular weight unsaturated compounds) to thiols (-SH) in the multifunctional thiol compound is 0.8:1 to 1:0.8 or even 0.9:1 to 1:0.9. If terminal C-C triple bonds are present in the curable composition, then more thiol will be needed.

[0046] When making the curable composition, the composition is substantially free of solvents. As used herein, “substantially free of solvents” refers to the curable compositions having less than 5, 4, 3, 2, 1, or even 0.5 wt % of non-polymerizable (e.g., organic) solvent. The concentration of solvent can be determined by known methods, such as gas chromatography (for example as described in ASTM D5403- 93). It should be noted that whether the curable composition is substantially solvent free or solvent free, no solvent is deliberately added to the composition. The term “solvents” is used herein consistent with the generally understood term of art and encompassing volatile organic and non-organic materials that are liquids at room temperature.

[0047] In some embodiments, the curable composition comprises at least one free radical initiator. Typically, the initiator is a photoinitiator, meaning that the initiator is activated by light, generally ultraviolet (UV) light, although other light sources could be used with the appropriate choice of initiator, such as visible light initiators, infrared light initiators, and the like. Thus, the curable compositions aregenerally curable by UV or visible light, typically UV light. Photoinitiators are known in the art. Examples of suitable free radical photoinitiators include OMNIRAD 4265, OMNIRAD 184, OMNIRAD 651, OMNIRAD 1173, OMNIRAD 819, OMNIRAD TPO, OMNIRAD TPO-L, commercially available from IGM Resins, Charlotte, NC. Particularly suitable photoinitiators include those that feature high absorbance above 365 nm wavelength. These include the acylphosphine oxide family of photoinitiators such as OMNIRAD TPO, OMNIRAD TPO-L, and OMNIRAD 819.

[0048] If an initiator is used, generally, the initiator is used in amounts of 0.01 to 10 parts by weight, more typically 0.1 to 2.0 parts by weight relative to 100 parts by weight of total reactive components (i.e., thiols, -enes, and -ynes) in the curable composition.

[0049] In some embodiments, the curable composition may include additional optional non-curable components, as long as such components do not interfere with curing of the curable composition and do not adversely affect the properties of the cured composition. The curable compositions may also contain polymerization inhibitors, UV absorbers, light stabilizers (e.g., hindered amine light stabilizers (HALS)), adhesion promoters, sensitizers, synergists, antioxidants, catalysts, dispersants, desiccants, surfactants, leveling agents, and the like as needed or desired.

[0050] In some embodiments, the curable composition further comprises an polymerization inhibitor and / or thermal stabilizer. Generally, these polymerization inhibitors and / or thermal stabilizers are added to the curable composition at an amount of 1 mM to 1 M. Exemplary inhibitors include BHT (2,6-di-t- butyl-p-cresol), MEHQ (4-methoxyphenol), and pyrogallol. Exemplary thermal stabilizers include (4- methoxyphenol, pyrogallol, or 4-tert-butyl-1,2-dihydroxybenzene. Acidic compounds can also be used as co-stabilizers, including benzoic acid, benzenesulfonic acid, phenylphosphonic acid, and vinylphosphonic acid. The typical concentration of the co-stabilizer in the curable composition ranges from 1mM to 1M. Useful antioxidants include but are not limited to amines, such as N-N' di-ß-naphthyl-1,4- phenylenediamine, available as “AGERITE D”; phenolics, such as 2,5-di-(t-amyl) hydroquinone, available as “SANTOVAR A”, available from Monsanto Chemical Co., tetrakis[methylene 3-(3',5'-di- tert-butyl-4'-hydroxyphenyl)propianate]methane, available as “IRGANOX 1010” from Ciba-Geigy Corp., and 2-2'-methylenebis(4-methyl-6-tert butyl phenol), available as Antioxidant 2246; and dithiocarbamates, such as zinc dithiodibutyl carbamate.

[0051] In some embodiments, the curable compositions have a viscosity of 100 centipoise (cP) or less at temperatures from room temperature to about 60°C. In some embodiments, the curable compositions have a viscosity at room temperature of at least 1, 2, 3, 4, or even 5 cp; and at most 100, 80, 60, 50, 40, 30, 25, 20, 15, or even 10 cP. In some embodiments, the curable compositions have a viscosity at 35°C of at least 1, 2, 3, 4, or even 5 cp; and at most 100, 80, 60, 50, 40, 30, 25, 20, 15, or even 10 cP. In some embodiments, the curable compositions have a viscosity at 60°C of at least 1, 2, 3, 4, or even 5 cp; and at most 30, 25, 20, 15, or even 10 cP as measured by a viscometer at ambient conditions. For example, the viscosity may be measured by taking 17mL of the curable composition and loaded it into a 25mm diameter double gap coaxial concentric cylinder apparatus on a viscometer (BOHLIN VISCO 88, Malvern Instruments Ltd, Malvern, UK). Water, heated to 25°C can be recirculated in a thermal jacket onthe double gap cell of the viscometer to maintain a constant temperature during testing. For example, the system can be equilibrated for 30 minutes prior to taking each measurement. The shear rate may be ramped from 100 to 1000 Hz at 100 hz intervals, and measurements repeated three times to determine the average viscosity.

[0052] The curable compositions may be deposited onto a surface using techniques known in the art, including conventional coating techniques, such as bar, roll, curtain, rotogravure, spray, or dip coating techniques. The curable compositions disclosed herein may be especially useful as the organic layer in thin film encapsulation parts. Often, printing techniques, such as inkjet printing are used to deposit these organic layers.

[0053] A wide variety of substrates are suitable for the articles of this disclosure. Suitable substrates include a wide array of flexible and non-flexible substrates. For example, the substrate may be glass, silicon nitride, silicon oxynitride, or a relatively thick layer of a polymeric material such as PMMA (polymethyl methacrylate) or PC (polycarbonate). Alternatively, the substrate may be flexible polymeric film such as films of PET (polyethylene terephthalate), PEN (polyethylene naphthalate), PC (polycarbonate), polyimide, PEEK (polyetherether ketone), and the like. In some embodiments, the substrate comprises a thermally sensitive substrate. A wide variety of thermally sensitive substrates are suitable, for example, an OLED panel.

[0054] The curable compositions can be exposed to thermal or photo radiation to initiate the reaction of the thiols with the carbon-carbon doubles of the hyperbranched polymer, resulting in a cured composition. The curable composition can be exposed to ultraviolet radiation having an ultraviolet (UV) A maximum in a range of 280 to 425 nanometers. Ultraviolet light sources can be of various types. Low light intensity lights such as blacklights, generally provide intensities ranging from 0.1 or 0.5 mW / cm2 (milliWatts per square centimeter) to 10 mW / cm2 (as measured in accordance with procedures approved by the United States National Institute of Standards and Technology as, for example, with a UVIMAP UM 365 L-S radiometer manufactured by Electronic Instrumentation & Technology, Inc., in Sterling, VA). High light intensity sources generally provide intensities greater than 10, 15, or 20 mW / cm2 ranging up to 450 mW / cm2 or greater. In some embodiments, high intensity light sources provide intensities up to 500, 600, 700, 800, 900 or 1000 mW / cm2. UV light to polymerize the monomer component(s) can be provided by various light sources such as light emitting diodes (LEDs), blacklights, medium pressure mercury lamps, etc. or a combination thereof. The reagents can also be polymerized with higher intensity light sources as available from Fusion UV Systems Inc. The UV exposure time for polymerization and curing can vary depending on the intensity of the light source(s) used. For example, complete curing with a low intensity light course can be accomplished with an exposure time ranging from about 30 to 300 seconds; whereas complete curing with a high intensity light source can be accomplished with shorter exposure time ranging from about 5 to 20 seconds. Partial curing with a high intensity light source can typically be accomplished with exposure times ranging from about 2 seconds to about 5 or 10 seconds.

[0055] Generally, this cured layer will have a refractive index of at least 1.600, 1.610, 1.620, 1.630, 1.640, 1.650, 1.660, 1.670, or even 1.680 when measured at 450 nm. High index nanoparticles, such as polymeric, metal, or metal oxide particles having a refractive index of at least 1.6 are typically used to increase the refractive index of the cured layer. However, advantageously, the cured compositions of the present disclosure have a high refractive index without the use of nanoparticles.

[0056] In some embodiments, the cured composition has a glass transition temperature of at least -20, - 10, 10, 20, 30, 40, 45, 50 or even 54°C and at most 120, 110, 100, 90, or even 80°C. The terms “Tg” and “glass transition temperature” are used interchangeably. If measured, Tg values at the midpoint (or half height) are determined by Differential Scanning Calorimetry (DSC) at a scan rate of 10°C / minute using the second heating. In some embodiments, the cured composition has a Tg higher (for example at least 5, 10, 20, or even 30 °C higher) than the same sample, wherein the hyperbranched polymer is replaced with Si(vinyl)4.

[0057] Ideally, the cured composition is optically clear. Unless otherwise indicated, "optically clear" refers to a layer, film, or article that has a high light transmittance over at least a portion of the visible light spectrum (about 400 to about 700 nm), and that exhibits low haze. Typically, optically clear layers, films, or articles have visible light transmittance values of at least 85%, or even 90%, often at least 95%, and haze values of 5% or less, often 2% or less using a technique such as ASTM D1003-21.

[0058] Also disclosed herein are articles. A wide variety of articles may be prepared utilizing the curable compositions described above. The articles may be relatively simple articles such as a substrate with a layer of cured composition disposed on it as shown in Fig.1, where article 100 comprises substrate 120 with cured organic layer 110 disposed on the substrate. Substrate 120 includes a wide array of flexible and non-flexible substrates. For example, substrate 120 may be glass, silicon nitride, silicon oxynitride, or a relatively thick layer of a polymeric material such as PMMA (polymethyl methacrylate) or PC (polycarbonate). Alternatively, substrate 120 may be flexible polymeric film such as films of PET (polyethylene terephthalate), PEN (polyethylene naphthalate), PC (polycarbonate), polyimide, PEEK (polyetherether ketone), and the like. Cured organic layer 110 is the cured layer derived from the curable compositions described herein. In some embodiments, the cured organic layer has a thickness of from 1- 50 micrometers, in some embodiments from 5-30 micrometers.

[0059] In other embodiments, the articles are more complex, such as multilayer articles comprising a substrate, and an inorganic barrier layer, with a cured organic layer between them, where the cured layer functions as a decoupling layer. The substrate may optionally have an inorganic coating layer present on its surface, so that the cured organic layer may be in contact with substrate surface or with the optional inorganic coating layer.

[0060] In some embodiments, the articles comprise a substrate with a first major surface and a second major surface, a cured organic layer with a first major surface and a second major surface, where the first major surface of the cured organic layer is adjacent to at least a portion of the second major surface of the substrate.

[0061] Figure 2 shows a device that includes a multilayer article of the present disclosure. Figure 2 shows article 200 comprising substrate 230 with device 240 disposed on substrate 230. Inorganic barrier layer 250 is in contact with device 240 and cured organic layer 210 is in contact with the inorganic barrier layer 250. Figure 2 also includes optional inorganic layer 260 that is in contact with cured organic layer 210. Optional layer 270 is in contact with optional inorganic layer 260 and also with substrate 280. Additionally, between optional layer 260 and optional layer 270, there may be optional alternating pairs of layers of cured organic (210) and inorganic (260) layers. For clarity these optional layers are not shown, but one can readily envision a stack of layers in the sequence 250 / 210 / 260 / 210 / 260, or 250 / 210 / 260 / 210 / 260 / 210 / 260, and so on.

[0062] The curable compositions disclosed herein can be cured and find use as an organic layer in a thin film encapsulation part. These organic layers should be deposited onto surfaces in a precise and consistent manner, which is usually done using printing techniques. In printing techniques, the curable composition that upon curing forms a polymer, is printed onto a substrate surface to form a layer. A wide variety of printing techniques can be used, with inkjet printing being particularly desirable because of the excellent precision of inkjet printing. Because the curable compositions may be printable, they may be herein also referred to as inks. The curable compositions need not be used as inks, that is to say that they need not be printed and then cured, the curable compositions can be delivered to substrate surfaces in a wide variety of ways, but they are capable of being printed. In particular, the printable compositions of this disclosure are typically capable of being inkjet printed, which means that they have the proper viscosity and other attributes required to be inkjet printed. The term “inkjet printable” is not a process description or limitation, but rather is a material description, meaning that the curable compositions are capable of being inkjet printed, and not that the compositions necessarily have been inkjet printed. In this disclosure, curable compositions, which may be considered “inks”, that are capable of being printed, are described which have a number of traits that make them suitable for the formation of layers within multilayer optical devices. As mentioned above, the curable compositions of the present disclosure are substantially free of solvent, which is advantageous as drying coating to remove solvent can not only decrease the thickness of the layer, but also adversely affect the surface smoothness and may also create defects in the coating. In many applications for optical devices, it is desired that the coatings be precise, that is to say that they do not lose thickness or smoothness upon drying. Therefore, the curable compositions of the present disclosure are preferably “100% solids”, meaning that they do not contain volatile solvents and that all of the mass that is deposited on a surface remains there, no volatile mass is lost from the coating.

[0063] The thickness of the cured composition is limited by the application used. For thin film encapsulation products, typically the cured organic layer has a thickness of from 1-50 micrometers, in some embodiments from 5-30 micrometers. Additionally, in many embodiments, the cured organic layer has a surface roughness of less than or equal to 10 nanometers, in some embodiments less than or equal to 5 nanometers.

[0064] An example of an optical device that utilizes thin film layers are OLED (organic light-emitting diode) devices. In particular, the organic light-emitting devices are susceptible to degradation from the permeation of certain liquids and gases, such as water vapor and oxygen. To reduce permeability to these liquids and gases, barrier coatings are applied to the OLED device. Typically, these barrier coatings are not used alone, rather a barrier stack is used which can include multiple dyads. Dyads are two-layer structures that include a barrier layer (i.e., inorganic layer) and decoupling layer (i.e., organic layer). The decoupling layer provides a planarized and / or smooth surface for the deposition of the inorganic barrier layer.

[0065] The inorganic barrier layer 250 in contact with cured organic layer 210 can be prepared from a variety of materials including metals, metal oxides, metal nitrides, metal oxynitrides, metal carbides, metal oxyborides, and combinations thereof. A wide range of metals are suitable for use in the metal oxides, metal nitrides, and metal oxynitrides, particularly suitable metals include Al, Zr, Si, Zn, Sn, and Ti. One particularly suitable inorganic barrier layer material is silicon nitride.

[0066] The thickness of the inorganic barrier layer 250 is not particularly limited, generally it is between 20 nanometers and 1 micrometer (1000 nanometers). More typically the thickness is from 20 nanometers to 100 nanometers.

[0067] Optional inorganic barrier layer 260 is of a similar thickness as inorganic barrier layer 250 and may comprise the same inorganic material, or it may be a different inorganic material.

[0068] One embodiment of the device 200 is a touch sensing device. In this device, substrate 230 is a thin film transistor, device 240 is an OLED device, optional layer 270 is an optically clear adhesive layer, and substrate 280 is a touch sensor.

[0069] In some embodiments, the curable composition is disclosed onto the surface of a substrate and then cured to form a cured organic layer. In some embodiments, an inorganic barrier layer is disposed onto the exposed surface of the cured organic layer.

[0070] In some embodiments, the curable composition can be printed and then cured to form a layer. In some embodiments, the cured composition has a thickness of from 1 to 16 micrometers, and a surface roughness of less than or equal to 5 nanometers. In many embodiments, the disposing of the curable composition on the second major surface of the substrate to form a curable layer comprises printing, especially inkjet printing. As described above, inkjet printing has a variety of desirable features that make it particularly suitable for preparing the curable layer, including the ability to deposit precise patterns on complex substrates and form a uniform coating with low surface roughness that is less than 10 nanometers, in some embodiments less than or equal to 5 nanometers.

[0071] In some embodiments, the article further comprises a device disposed on the second major surface of the substrate, and adjacent to the cured organic layer.

[0072] In some embodiments, the substrate comprises an inorganic coating layer present on the second major surface, such that the first major surface of the cured organic layer is in contact with the inorganic coating layer.

[0073] The above-described constructions can also be used as components of more complex articles. In some embodiments, the article further comprises a device disposed on the second major surface of the substrate, and adjacent to the first major surface of the cured organic layer. In some embodiments, an inorganic coating layer is disposed on the device and on the second major surface of the substrate, such that the first major surface of the cured organic layer is in contact with the inorganic coating layer. In some specific embodiments, the device comprises an OLED (organic light-emitting diode). EXAMPLES

[0074] Unless otherwise noted, all parts, percentages, ratios, etc. in the examples and the rest of the specification are by weight, and all reagents used in the examples were obtained, or are available, from general chemical suppliers such as, for example, Millipore-Sigma Company, Saint Louis, Missouri, or Gelest, Morristown, Pennsylvania or may be synthesized by conventional methods. TABLE 1. Materials List Designation Description Si(vinyl)4 Tetravinylsilane, available under the trade designation “318266” from Millipore- Sigma Si(allyl)4 Tetraallylsilane, available under the trade designation “SIT7020.0” from Gelest (Morristown, PA) TAIC Triallylisocyanurate, available under the trade designation “I0279” from TCI (Portland OR) TVCH 1,2,4-Trivinylcyclohexane, available under the trade designation “0899” from TCI 13BDT 1,3-Benzenedithiol, available under the trade designation “B4371” from TCI 13BDMT 1,3-Benzenedimethanethiol, available under the trade designation “B3854” from TCI DMPT 2,3-Bis-2-mercaptoethylthio-1-propanethiol, available under the trade designation “Thiocure DMPT” from Bruno Bock GMBH, Marschact, Germany PETMP Pentaerythritol terakis(3-mercaptopropionate, available under the trade designation “381462” from Millipore-Sigma OV-POSS Octavinyl polyhedral oligosilsesquioxane (POSS), available under the trade designation “OL1170” from Hybrid Plastics (Hattiesburg, MS) HBP-1 Vinyl-terminated hyperbranched polycarbosilane, synthesized as described in below HBP-2 Vinyl-terminated hyperbranched polycarbosilane, synthesized as described in below TPO-L 2,4,6-Trimethylbenzoylphenyl-phosphinic acid ethyl ester, available from BASF (Florham Park, NJ)

[0075] Preparation of Hyperbranched Polymers (HBP1 and HBP2)

[0076] HBP1 was prepared as described for Polymer 1 in HYPERBRANCHED POLYMER, METHOD OF MAKING, AND CURABLE COMPOSITION INCLUDING THE SAME (Patent Application WO / 2022 / 058810, published 24 March 2022) with 6.14 mmol / g vinyl groups, Mn 2500, average vinyl functionality 15, and a core derived from tetravinylsilane and 1,4-bisdimethylsilylbenzene.

[0077] HBP2 was prepared via the same method from 1,2,4-trivinylcyclohexane and 1,4- bisdimethylsilylbenzene (5.62 mmol / g vinyl, Mn 2100, average vinyl functionality 12).

[0078] Refractive Index

[0079] Refractive index of the cured films on PET substrates was measured using a digital prism coupler (Model 2010, Metricon Inc., Pennington, NJ) at 450 nm at 20 °C.

[0080] Differential Scanning Calorimetry (DSC)

[0081] DSC samples were prepared for thermal analysis by weighing and loading the material into TA Instruments (New Castle, Delaware) aluminum DSC sample pans. The specimens were analyzed using the TA Instruments Discovery Differential Scanning Calorimeter (DSC - SN DSC1-0091, New Castle, DE) utilizing a heat-cool-heat method in standard mode (-155 °C to about 150°C at 10 °C / minute.). After data collection, the thermal transitions were analyzed using the TA Universal Analysis program. The glass transition temperatures were evaluated using the step change in the standard heat flow (HF) curves. The midpoint (half height) temperature of the second heat transition is reported.

[0082] Average Functionality

[0083] The average functionality of the resulting cured polymer was determined theoretically by adding together the product of the percentage present times the number of functional groups (i.e., S-H and C=C) present. For example, in sample C1 the average functionality is (0.67 x 2) + (0.33 x 4)=2.66.

[0084] Examples 1-7 (E1-E7) and Comparative Examples 1-10 (C1-C10)

[0085] Thiolene formulations were prepared from mixtures of liquid thiols and hyperbranched polymer and optional low molecular weight alkenes with mass ratios such that the thiol groups were in a one-to- one molar ratio with the carbon-carbon double bonds. TPO-L was added at 3 wt% and the formulation was mixed thoroughly. The liquid formulation was cast onto a polyethylene terephthalate (PET) substrate using a Meyer rod (number 10), and UV cured using a UV LED curing system (Clearstone Technologies Inc., Hopkins, MN, 395 nm, 100% intensity corresponding to 319 mW / cm2for 2 minutes at a distance of 1 cm from the surface of the sample). Transparent hardcoats were obtained. The samples were tested for glass transition temperature and refractive index, and the average functionality determined. The results are reported in Table 2.TABLE 2 Sample Formulations weight ratios Glass Transition Average Refractive provided Temperature (°C) Functionality Index (450nm) C1 67 / 3313BDT / Si(vinyl)4 43 2.66 1.743 C2 60 / 4013BDT / Si(allyl)4 27 2.80 1.706 C3 46 / 5413BDT / TAIC 41 2.54 1.675 C4 57 / 4313BDT / TVCH 14 2.43 1.682 E1 55 / 20 / 2513BDT / OV-POSS / 44 3.70 1.694 Si(allyl)4 E2 30 / 7013BDT / HBP1 51 11.1 1.662 E3 28 / 7213BDT / HBP2 9 & 108 9.20 1.618 C5 71 / 2913BDMT / Si(vinyl)4 30 2.58 1.688 C6 50 / 5013BDMT / TAIC 25 2.50 1.644 C7 61 / 3913BDMT / TVCH 11 2.39 1.648 E4 60 / 4013BDMT / HBP1 44 7.20 1.655 C8 72 / 28 DMPT / Si(vinyl)4 -61 3.28 1.600 C9 62 / 38 DMPT / TVCH -43 3.00 1.715 E5 60 / 40 DMPT / HBP1 -17 7.80 1.647 E6 33 / 67 DMPT / HBP2 -10 9.03 1.634 C10 78 / 22 PETMP / Si(vinyl)4 -26 4.00 Not measured E7 51 / 49 PETMP / HBP1 -4 7.92 1.657

[0086] Foreseeable modifications and alterations of this invention will be apparent to those skilled in the art without departing from the scope and spirit of this invention. This invention should not be restricted to the embodiments that are set forth in this application for illustrative purposes. To the extent that there is any conflict or discrepancy between this specification as written and the disclosure in any document mentioned or incorporated by reference herein, this specification as written will prevail.

Claims

What is claimed is:

1. A curable composition comprising: (i) a hyperbranched polymer comprising a plurality of first terminal carbon-carbon double bonds, wherein the hyperbranched polymer comprises a reaction product of components: (a) at least one unsaturated compound consisting of C, H, and optionally Si atoms, O atoms, or Si and O atoms, and having p second terminal carbon-carbon double bonds, wherein each p is independently an integer greater than or equal to 2; (b) at least one organosilane compound consisting of C, H, Si, and optionally O atoms and having q Si-H groups, wherein each q is independently an integer greater than or equal to 2; and (c) at least one hydrosilylation reaction catalyst, wherein p / q is at least 2.1; and (ii) at least one multifunctional thiol comprising at least 2 thiol groups; and wherein the curable composition is substantially free of solvent.

2. The curable composition of claim 1, wherein p / q is at least 3.

3. The curable composition of any one of the previous claims, wherein the at least one organosilane compounds in component (b) is independently represented by the formula Z(SiR12H)awherein Z is an a-valent radical composed of C, H, and optionally O, wherein Z has from 1 to 12carbon atoms, each R1is independently a hydrocarbyl group having from 1 to 12 carbon atoms, and a isan integer from 2 to 8.

4. The curable composition of claim 3, wherein Z comprises a phenylene group.

5. The curable composition of any one of the previous claims, wherein the at least one unsaturated compound in component (a) is independently represented by the formula Si(OSiR22CH=CH2)b(R2CH=CH2)c(R3)dwherein each R2is independently a direct bond or a hydrocarbylene group having 1 to 12 carbonatoms, each R3is independently a hydrocarbyl group having from 1 to 12 carbon atoms, b is an integerfrom 0 to 4, c is an integer from 0 to 4, and d is an integer from 0 to 2, with the proviso that b + c ≥ 2 and b + c + d = 4.

6. The curable composition of claim 5, wherein the at least one first compound in component (a) is selected from the group consisting of tetravinylsilane, or tetraallylsilane.

7. The curable composition of any one of claims 1-4, wherein the at least one first compound in component (a) is a hydrocarbon having at least 3 vinyl or allyl groups, optionally, component (a) is trivinylcyclohexane.

8. The curable composition of any one of the previous claims, wherein the hyperbranched polymer has a molecular weight of at least 1000 g / mol and at most 5000 g / mol.

9. The curable composition of any one of the previous claims, wherein the curable composition further comprises a low molecular compound comprising at least 2 or more terminal unsaturated groups, wherein the terminal unsaturated groups are selected from an -ene or -yne group.

10. The curable composition of claim 9, wherein the low molecular weight compound has a molecular weight of less than 800 g / mol.

11. The curable composition of any one of the previous claims, wherein the ratio of thiol groups to the first terminal carbon-carbon double bonds is 1:0.8 to 0.8:

1.

12. The curable composition of any one of the previous claims, wherein the multifunctional thiol is an aromatic thiol.

13. The curable composition of any one of the previous claims, wherein the multifunctional thiol is 4- mercaptomethyl-1,8-dimercapt-3,6-dithiaoctane; 5,7-dimercaptomethyl-1,11-dimercapto-3,6, 9- trithiaundecane; 4, 8-dimercaptomethyl-1, 11-dimercapto-3,6,9-trithiaundecane; 4,7-dimercaptomethyl- 1,11-dimercapto-3,6,9-trithiaundecane, pentaerythritol tetrakis(3-mercaptoprionate), trimethylolpropane tris(3-mercaptopropionate, or mixtures thereof.

14. The curable composition of any one of the previous claims, wherein the curable composition further comprises a free radical initiator.

15. The curable composition of any one of the previous claims, wherein the curable composition has a refractive index greater than 1.610 (at 450 nm).

16. The curable composition of any one of the previous claims, wherein the curable composition has a Tg higher than a comparable example wherein the hyperbranched polymer is replaced with Si(vinyl)4.

17. The curable composition of any one of the previous claims, wherein the curable composition further comprises an inhibitor.

18. The curable composition of any one of the previous claims, wherein the curable composition further comprises a thermal stabilizer.

19. The curable composition of any one of the previous claims, wherein the curable composition further comprises an adhesion promoter.

20. The curable composition of any one of the previous claims, wherein the curable composition has a viscosity of 100 cps or less at a temperature of from room temperature to 35°C.

21. An article comprising: a substrate with a first major surface and a second major surface; a cured organic layer adjacent to at least a portion of the second major surface of the substrate, wherein the cured organic layer is derived from (i) a hyperbranched polymer comprising a plurality of first terminal carbon-carbon double bonds, wherein the hyperbranched polymer comprises a reaction product of components: (a) at least one unsaturated compound consisting of C, H, and optionally Si atoms, O atoms, or Si and O atoms, and having p second terminal carbon-carbon double bonds, wherein each p is independently an integer greater than or equal to 2; (b) at least one organosilane compound consisting of C,H, Si, and optionally O atoms and having q Si-H groups, wherein each q is independently an integer greater than or equal to 2; and (c) at least one hydrosilylation reaction catalyst, wherein p / q is at least 2.1; and (ii) at least one multifunctional thiol comprising at least 2 thiol groups; and an inorganic barrier layer in contact with the cured organic layer, wherein the cured organic layer has a refractive index of at least 1.610 (measured at 450 nm).

22. The article according to claim 21, wherein the cured organic layer is optically clear.

23. The article according to any one of claims 21 to 22, wherein the cured organic layer has a glass transition temperature of at least 10 ^C.

24. The article according to any one of claims 21 to 23, wherein the cured organic layer has a thickness of from 1 to 16 micrometers, and a surface roughness of less than or equal to 5 nanometers.

25. The article according to any one of claims 21 to 24, wherein the article further comprises a device disposed on the second major surface of the substrate, and adjacent to the cured organic layer.

26. The article of claim 25, wherein the device comprises an OLED (organic light-emitting diode).

27. A method of preparing an article comprising: providing a substrate with a first major surface and a second major surface; providing a curable composition according to any one of claims 1-25, disposing the curable composition on at least a portion of the second major surface of the substrate to form a curable layer; curing the curable layer to form a cured organic layer, wherein the cured organic layer has a refractive index of at least 1.610 measured at 450 nm; and depositing an inorganic barrier layer on the cured organic layer.

28. The method of claim 27, wherein disposing of the curable composition on the second major surface of the substrate to form a curable layer comprises inkjet printing to a thickness of from 1 to 16 micrometers.

29. The method according to any one of claims 27 to 28, further comprising providing a device; and disposing the device on the second major surface of the substrate prior to disposing the curable composition on the second major surface of the substrate to form a curable layer.

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