Curable polyorganosiloxane composition and methods for the preparation and use thereof

Abstract

A curable polyorganosiloxane composition and method for its preparation are provided. The curable polyorganosiloxane includes a base polyorganosiloxane, a polyorganohydrogensiloxane crosslinker, a catalyst composition, and an antioxidant. The curable polyorganosiloxane composition can be cured to form a polyorganosiloxane release coating.

Description

POLYORGANOSILOXANE COMPOSITION AND METHODS FOR THE PREPARATION AND USE THEREOF CROSS REFERENCE TO RELATED APPLICATIONS

[0001] This application claims the benefit of U.S. Provisional Patent Application Serial No. 63 / 688,415 filed on 29 August 2024 under 35 U.S.C. §119 (e). U.S. Provisional Patent Application Serial No.63 / 688,415 is hereby incorporated by reference. FIELD

[0002] A curable polyorganosiloxane composition and method for its preparation and use are disclosed. More particularly, this invention relates to said curable polyorganosiloxane composition, which contains an aldehyde-functional polyorganosiloxane and a polyorganohydrogensiloxane that cure via hydrosilylation reaction to form a cured product, such as a release coating. INTRODUCTION

[0003] Hydrosilylation reactions of an alkenyl-functional polydiorganosiloxane, and a polyorganohydrogensiloxane crosslinker catalyzed with a platinum catalyst are known in the art for preparing curable polyorganosiloxane compositions, such as polyorganosiloxane release coating compositions. Hydrosilylation reaction curable polyorganosiloxane compositions may suffer from various drawbacks including that the platinum catalyst is expensive, easily inhibited or poisoned, and hard to remove after curing, which can result in cure drift over time.

[0004] Hydrosilylation reaction curable release coating compositions typically contain inhibitors such as alkynyl alcohols, which may be difficult to use to provide sufficient bathlife while still allowing for rapid cure of said composition on a substrate, such as a paper or plastic film. Hydrosilylation reaction curable release coating compositions are typically supplied to coating equipment from a coating bath. The coating bath is supplied to the coating equipment to form a thin film (e.g., the composition stored in a bulk in a container and supplied from the container to coating equipment forming a thin film of the hydrosilylation reaction curable release coating composition on rolls in a roll coater). Working time of the hydrosilylation reaction curable release coating composition can be divided into bulk bathlife and thin film bathlife. Bulk bathlife is the time when viscosity of the coating bath (bulk) doubles compared to the initial viscosity of the coating bath at 40° C. Thin film bathlife denotes the time when a 2 mil coating film is cured at RT. If bulk bathlife of a hydrosilylation reaction curable release coating composition is too short, there is a risk of gelling the coating bath, piping, or other parts of the coating equipment. If the thin film bathlife is too short, there is a risk of gelling the portions ofwith the thin film, e.g., the coater rolls. Long working time seeminglycan be achieved by lowering the platinum level or increasing the hydrosilylation reaction inhibitor level. However, either increasing hydrosilylation reaction inhibitor content or lowering platinum content can cause the hydrosilylation reaction curable release coating composition to cure too slowly, such that when said composition is coated on a substrate, insufficient cure in the coating equipment may cause the resulting release coating to have poor rub off resistance. SUMMARY

[0005] A curable polyorganosiloxane composition comprises: (A) an aldehyde-functional polyorganosiloxane, (B) a polyorganohydrogensiloxane, and (C) a catalyst composition. The catalyst composition comprises: (i) a halogenated arylborane Lewis acid, optionally (ii) a Lewis basic amine, and optionally (iii) a solvent. A method for preparing the curable polyorganosiloxane composition is provided. The curable polyorganosiloxane composition is useful in various applications, including polyorganosiloxane release coating applications. DETAILED DESCRIPTION

[0006] The curable polyorganosiloxane composition (composition), introduced above, comprises: (A) an aldehyde-functional polyorganosiloxane, (B) a polyorganohydrogensiloxane, and (C) a catalyst composition. The composition may optionally further comprise an additional starting material, such as (D) an antioxidant, and a filler. Alternatively, when the composition will be used to prepare a release coating, the additional starting material may be selected from the group consisting of (D) the antioxidant, (E) a release modifier, (F) an anchorage additive, (G) a solvent, and / or (H) an anti-mist additive.

[0007] Starting material (A) is an aldehyde-functional polyorganosiloxane. Aldehyde- functional polyorganosiloxanes suitable for use herein are known and may be made by known methods, such as those described in US Patent 5021601 to Frances et al.; US Patent 5739246 to Graiver et al.; US Patent 7696294 to Asirvatham; and US Patent 7999053 to Sutton et al.; European Patent Application Publication EP 0392948 A1 to Frances, and PCT Patent Application Publication WO2006027074 to Kühnle et al.

[0008] Alternatively, the aldehyde-functional polyorganosiloxane may be prepared by a hydroformylation process. This hydroformylation process comprises 1) combining, under conditions to catalyze hydroformylation reaction, starting materials comprising a gas comprising hydrogen and carbon monoxide, an alkenyl-functional polyorganosiloxane, and a hydroformylation reaction catalyst such as a rhodium / ligand complex, wherein the ligand may be a bisphosphite, a phosphoramidite, or a phosphine or phosphine amine. Step 1) of the hydroformylation process produces a hydroformylation reaction product comprising thepolyorganosiloxane. The hydroformylation process (or any other process inthe references cited above for making the aldehyde-functional polyorganosiloxane) may further comprise one or more additional steps such as: 2) recovering the aldehyde-functional polyorganosiloxane and removing the catalyst (e.g., rhodium / ligand complex from the hydroformylation reaction) from the aldehyde-functional polyorganosiloxane. Removing the catalyst may be performed by methods known in the art, including but not limited to adsorption (e.g., by contacting with an adsorbent such as activated carbon for a time sufficient to adsorb all or at least a portion of the catalyst) with subsequent filtration to remove the adsorbent, and / or membrane separation (e.g., nanofiltration). Suitable recovery methods are as described, for example, in US Patents 5681473 to Miller, et al.; 8748643 to Priske, et al.; and 10155200 to Geilen, et al. The hydroformylation process for making aldehyde-functional polyorganosiloxanes may be as described, for example, in US Patent Application Publication US20230242711 and PCT Patent Application Publication WO2023200934, both of which are hereby incorporated by reference for the purpose of disclosing suitable aldehyde-functional polyorganosiloxanes.

[0009] The aldehyde-functional polyorganosiloxane has at least two aldehyde-functional groups per molecule. Each aldehyde-functional group is bonded to a silicon atom in the polyorganosiloxane and may have , wherein G is a divalent hydrocarbyl group of 2 to 8 carbon atomsunsaturation. G may be linear or branched. Examples of divalent hydrocarbyl groups for G include alkane-diyl groups of empirical formula -CuH2u-, where subscript u is 2 to 8. The alkane-diyl group may be a linear alkane-diyl, e.g., -CH2-CH2-, -CH2-CH2-CH2-, -CH2-CH2-CH2-CH2-, or -CH2-CH2-CH2-CH2- CH2-CH2-, or a branched alkane- or. Alternatively, each G may be an alkane-diyl group of 2 to 6 carbon atoms;2, 3, or 6 carbon atoms; and alternatively 2 carbon atoms.functional polyorganosiloxane may comprise unit formula (A1): (R73SiO1 / 2)c(R72R8SiO1 / 2)d(R72SiO2 / 2)e(R7R8SiO2 / 2)f(R7SiO3 / 2)g(R8SiO3 / 2)h(SiO4 / 2)i(ZO1 / 2)j; wherein each R7is a monovalent hydrocarbyl group free of aliphatic unsaturation, e.g., each R7may be independently selected from the group consisting of an alkyl group of 1 to 18 carbon atoms and an aryl group of 6 to 18 carbon atoms; each R8is the aldehyde-functional group of formula , wherein G is the divalent hydrocarbon group free of aliphatic 8 carbon atoms described above; each Z is independently selected fromthe group consisting of a hydrogen atom, an alkyl group of 1 to 18 carbon atoms, and an aryl groups of 6 to 18 carbon atoms; subscripts c, d, e, f, g, h, and i are integers each representing an average number of siloxane units per molecule, and subscripts c, d, e, f, g, h, and i have values such that: c ≥ 0, d ≥ 0, e ≥ 0, f ≥ 0, g ≥ 0, h ≥ 0, a quantity (d + f + h) ≥ 2, i ≥ 0, and 10,000 ≥ (c + d + e + f + g + h + i) ≥ 2, and subscript j has a value such that 1.5 > j / (g + h + i) > 0.

[0011] In unit formula (A1), each R7may be independently selected from the group consisting of an alkyl group of 1 to 18 carbon atoms and an aryl group of 6 to 18 carbon atoms. Suitable alkyl groups for R7may be linear, branched, cyclic, or combinations of two or more thereof. The alkyl groups are exemplified by propyl (including n-propyl and / or isopropyl), butyl (including n-butyl, tert-butyl, sec-butyl, and / or isobutyl); pentyl, hexyl, heptyl, octyl, decyl, dodecyl, undecyl, and octadecyl (and branched isomers having 5 to 18 carbon atoms), and the alkyl groups are further exemplified by cycloalkyl groups such as cyclopropyl, cyclobutyl, cyclopentyl, and cyclohexyl. Alternatively, the alkyl group for R7may be selected from the group consisting of methyl and ethyl. Alternatively, the alkyl group for R7may be methyl. Suitable aryl groups for R7may be monocyclic or polycyclic and may have pendant hydrocarbyl groups. For example, the aryl groups for R7include phenyl, tolyl, xylyl, and naphthyl and further include aralkyl groups such as benzyl, 1-phenylethyl and 2-phenylethyl. Alternatively, the aryl group for R7may be monocyclic, such as phenyl, tolyl, or benzyl; alternatively the aryl group for R7may be phenyl. Alternatively, each R7may be independently selected from the group consisting of an alkyl group of 1 to 12 carbon atoms and an aryl group of 6 to 12 carbon atoms Alternatively, each R7may be independently selected from the group consisting of an alkyl group of 1 to 6 carbon atoms and an aryl group of 6 to 10 carbon atoms. Alternatively, each R7may be selected from methyl and phenyl. Alternatively, each R7may be methyl.

[0012] In unit formula (A1), each Z is independently selected from the group consisting of H and an alkyl group of 1 to 18 carbon atoms, which may be as described above with respect to R7.Z may be hydrogen or an alkyl group of 1 to 6 carbon atoms. Alternatively,each Z may be hydrogen or methyl.

[0013] In unit formula (A1), each R8is the aldehyde-functional group described above.

[0014] Alternatively, the aldehyde-functional polyorganosiloxane may comprise (A2) a linear polydiorganosiloxane having, per molecule, at least one aldehyde-functional group; alternatively at least two aldehyde-functional groups (e.g., when in the unit formula (A1) for the aldehyde- functional polyorganosiloxane above, subscripts g = h = i = 0). For example, said aldehyde- functional polydiorganosiloxane may comprise unit formula (A3): (R73SiO1 / 2)c(R8R72SiO1 / 2)d(R72SiO2 / 2)e(R7R8SiO2 / 2)f, where R7and R8are as described above, subscript c is 0, 1, or 2; subscript d is 0, 1, or 2, subscript e ≥ 0, subscript f ≥ 0, with the provisos that a quantity (d + f) ≥ 1, a quantity (c + d) = 2, and a quantity (c + d + e + f) ≥ 2. Alternatively, in the unit formula (A3) for the linear aldehyde-functional polyorganosiloxane, above, the quantity (c + d + e + f) may be at least 3, alternatively at least 4, and alternatively > 50. At the same time said formula, the quantity (a + b + c + d) may be less than or equal to 10,000; alternatively less than or equal to 4,000; alternatively less than or equal to 2,000; alternatively less than or equal to 1,000; alternatively less than or equal to 500; alternatively less than or equal to 250; and alternatively less than or equal to 200.

[0015] Alternatively, (A) the aldehyde-functional polyorganosiloxane may be branched. For example, (A4) the branched aldehyde-functional polyorganosiloxane may comprise a Q branched polyorganosiloxane of unit formula (A5): (R73SiO1 / 2)q(R7 2R8SiO1 / 2)r(R7 2SiO2 / 2)s (SiO4 / 2)t, where R7and R8are as described above, and subscripts q, r, s, and t have average values such that 2 ≥ q ≥ 0, 4 ≥ r ≥ 0, 995 ≥ s ≥ 4, t = 1, (q + r) = 4, and (q + r + s + t) has a value sufficient to impart a viscosity > 170 mPa·s measured by rotational viscometry (as described below with the test methods) to the branched polyorganosiloxane. Alternatively, viscosity may be > 170 mPa·s to 1000 mPa·s, alternatively > 170 to 500 mPa·s, alternatively 180 mPa·s to 450 mPa·s, and alternatively 190 mPa·s to 420 mPa·s.

[0016] Alternatively, (A5) the Q branched aldehyde-functional polyorganosiloxane may comprise formula (A6): [R8R72Si-(O-SiR72)n-O](4-m)-Si-[O-(R72Si-O)v-SiR73]m, where R7and R8are as described above; and subscripts v, m, and n have values such that 200 ≥ v ≥ 1, 2 ≥ m ≥ 0, and 200 ≥ n ≥ 1.

[0017] Alternatively, (A4) the branched aldehyde-functional polyorganosiloxane may comprise a T branched polyorganosiloxane (silsesquioxane) of unit formula (A7): (R73SiO1 / 2)aa(R8R72SiO1 / 2)bb(R72SiO2 / 2)cc(R8R7SiO2 / 2)ee(R7SiO3 / 2)dd, where R7and R8are as described above, subscript aa ≥ 0, subscript bb > 0, subscript cc is 15 to 995, subscript dd > 0, and subscript ee ≥may be 0 to 14, alternatively 0 to 10. Alternatively, subscript aa may have avalue such that: 12 ≥ aa ≥ 0; alternatively 10 ≥ aa ≥ 0; alternatively 7 ≥ aa ≥ 0; alternatively 5 ≥ aa ≥ 0; and alternatively 3 ≥ aa ≥ 0. Alternatively, subscript bb ≥ 1. Alternatively, subscript bb ≥ 3. Alternatively, subscript bb may have a value such that: 12 ≥ bb > 0; alternatively 12 ≥ bb ≥ 3; alternatively 10 ≥ bb > 0; alternatively 7 ≥ bb > 1; alternatively 5 ≥ bb ≥ 2; and alternatively 7 ≥ bb ≥ 3. Alternatively, subscript cc may have a value such that: 800 ≥ cc ≥ 15; and alternatively 400 ≥ cc ≥ 15. Alternatively, subscript ee may have a value such that: 800 ≥ ee ≥ 0; 800 ≥ ee ≥ 15; and alternatively 400 ≥ ee ≥ 15. Alternatively, subscript ee may b 0. Alternatively, a quantity (cc + ee) may have a value such that 995 ≥ (cc + ee) ≥ 15. Alternatively, subscript dd ≥ 1. Alternatively, subscript dd may be 1 to 10. Alternatively, subscript dd may have a value such that: 10 ≥ dd > 0; alternatively 5 ≥ dd > 0; and alternatively dd = 1. Alternatively, subscript dd may be 1 to 10, alternatively subscript dd may be 1 or 2. Alternatively, when subscript dd = 1, then subscript bb may be 3 and subscript cc may be 0. The values for subscript bb may be sufficient to provide the silsesquioxane of unit formula (A7) with an aldehyde content of 0.1% to 1%, alternatively 0.2% to 0.6%, based on the weight of the silsesquioxane.

[0018] Alternatively, (A) the aldehyde-functional polyorganosiloxane may comprise (A8) an aldehyde-functional polyorganosiloxane resin, such as (A9) an aldehyde-functional polyorganosilicate resin and / or (A10) an aldehyde-functional silsesquioxane resin. Such resins may be prepared, for example, by hydroformylating an alkenyl-functional polyorganosiloxane resin, as described in the references cited above. The aldehyde-functional polyorganosilicate resin comprises monofunctional units (“M’” units) of formula RM’3SiO1 / 2and tetrafunctional silicate units (“Q” units) of formula SiO4 / 2, where each RM’may be independently selected from the group consisting of R7and R8as described above. Alternatively, each RM’may be selected from the group consisting of an alkyl group, an aldehyde-functional group of the formula shown above, and an aryl group. Alternatively, each RM’may be selected from methyl, (propyl- aldehyde) and phenyl. Alternatively, at least one-third, alternatively at least two thirds of the RM’groups are methyl groups. Alternatively, the M’ units may be exemplified by (Me3SiO1 / 2), (Me2PhSiO1 / 2), and (Me2RPr-AldSiO1 / 2). The polyorganosilicate resin is soluble in solvents such as those described herein as starting material (C)(iii), exemplified by liquid hydrocarbons, such as benzene, ethylbenzene, toluene, xylene, and heptane, or in liquid non-functional organosilicon compounds such as low viscosity linear and cyclic polydiorganosiloxanes.

[0019] When prepared, the polyorganosilicate resin comprises the M’ and Q units described above, and the polyorganosiloxane further comprises units with silicon bonded hydroxyl groups, and / or hydrolyzable groups, described by moiety (ZO1 / 2), above, and may comprise neopentamer4, where RM’is as described above, e.g., the neopentamer may be tetrakis(trimethylsiloxy)silane.29Si NMR and13C NMR spectroscopies may be used to measure hydroxyl and alkoxy content and molar ratio of M’ and Q units, where said ratio is expressed as {M’(resin)} / {Q(resin)}, excluding M’ and Q units from the neopentamer. M’ / Q ratio represents the molar ratio of the total number of triorganosiloxy groups (M’ units) of the resinous portion of the polyorganosilicate resin to the total number of silicate groups (Q units) in the resinous portion. M’ / Q ratio may be 0.5 / 1 to 1.5 / 1, alternatively 0.6 / 1 to 0.9 / 1.

[0020] The Mn of the polyorganosilicate resin depends on various factors including the types of hydrocarbon groups represented by RM’that are present. The Mn of the polyorganosilicate resin refers to the number average molecular weight measured using GPC, when the peak representing the neopentamer is excluded from the measurement. The Mn of the polyorganosilicate resin may be 1,500 Da to 30,000 Da, alternatively 1,500 Da to 15,000 Da; alternatively >3,000 Da to 8,000 Da. Alternatively, Mn of the polyorganosilicate resin may be 3,500 Da to 8,000 Da.

[0021] Alternatively, the polyorganosilicate resin may comprise unit formula (A11): (R73SiO1 / 2)mm(R72R8SiO1 / 2)nn(SiO4 / 2)oo(ZO1 / 2)j, where Z, R7, and R8, and subscript j are as described above and subscripts mm, nn and oo have average values such that mm ≥ 0, nn > 0, oo > 0, and 0.5 < (mm + nn) / oo < 4. Alternatively, 0.6 < (mm + nn) / oo < 4; alternatively 0.7 < (mm + nn) / oo < 4, and alternatively 0.8 < (mm + nn) / oo < 4.

[0022] Alternatively, (A) the aldehyde-functional polyorganosiloxane may comprise (A10) the aldehyde-functional silsesquioxane resin, i.e., a resin containing trifunctional (T’) units. The aldehyde-functional silsesquioxane resin may have unit formula (A12): (R73SiO1 / 2)c(R72R8SiO1 / 2)d(R72SiO2 / 2)e(R7R8SiO2 / 2)f(R7SiO3 / 2)g(R8SiO3 / 2)h(ZO1 / 2)j; where R7and R8are as described above, subscript h > 1, 2 < (g + h) < 10,000; 0 < (c + d) / (g + h) < 3; 0 < (e + f) / (g + h) < 3; and 0 < j / (g + h) < 1.5. Alternatively, the aldehyde-functional silsesquioxane resin may comprise unit formula (A13): (R7SiO3 / 2)g(R8SiO3 / 2)h(ZO1 / 2)j, where R7, R8, Z, and subscripts g, h, and j are as described above. Alternatively, the alkenyl-functional silsesquioxane resin may further comprise difunctional (D’) units of formulae (R72SiO2 / 2)e(R7R8SiO2 / 2)f in addition to the T’ units described above, i.e., a D’T’ resin, where subscripts e and f are as described above. Alternatively, the aldehyde-functional silsesquioxane resin may further comprise monofunctional (M’) units of formulae (R73SiO1 / 2)c(R72R8SiO1 / 2)d, i.e., an M’D’T’ resin, where subscripts c and d are as described above for unit formula (A1).

[0023] One aldehyde-functional polyorganosiloxane may be used in the curable polyorganosiloxane composition of this invention. Alternatively, two or more aldehyde-that differ from one another may be used. For example, the aldehyde-functional polyorganosiloxanes may differ in at least one property such as structure, molecular weight, type of aldehyde-functional group, and selection of groups for R7. For example, a branched aldehyde-functional polyorganosiloxane may be used as starting material (A). Alternatively, a combination of a linear aldehyde-functional polyorganosiloxane and a resinous aldehyde-functional polyorganosiloxane may be used in addition to, or instead of, the branched aldehyde-functional polyorganosiloxane.

[0024] Starting material (B) in the curable polyorganosiloxane composition is a polyorganohydrogensiloxane having, per molecule, at least two silicon bonded hydrogen atoms. The polyorganohydrogensiloxane comprises two or more siloxane units selected from, HR92SiO1 / 2, R93SiO1 / 2, HR9SiO2 / 2, R92SiO2 / 2, R9SiO3 / 2, HSiO3 / 2 and SiO4 / 2 units, with the proviso that at least two units per molecule have a silicon bonded hydrogen atom. In the preceding formulae, each R9is an independently selected monovalent hydrocarbyl group as described and exemplified above for R7. Monovalent halogenated hydrocarbyl groups are exemplified by the hydrocarbyl groups described above, but having one or more hydrogen atoms replaced with a halogen atom, such as Cl or F. Examples of suitable monovalent halogenated hydrocarbon groups include, but are not limited to, chlorinated alkyl groups such as chloromethyl and chloropropyl groups; fluorinated alkyl groups such as fluoromethyl, 2-fluoropropyl, 3,3,3- trifluoropropyl, 4,4,4-trifluorobutyl, 4,4,4,3,3-pentafluorobutyl, 5,5,5,4,4,3,3-heptafluoropentyl, 6,6,6,5,5,4,4,3,3-nonafluorohexyl, and 8,8,8,7,7-pentafluorooctyl; chlorinated cycloalkyl groups such as 2,2-dichlorocyclopropyl, 2,3-dichlorocyclopentyl; and fluorinated cycloalkyl groups such as 2,2-difluorocyclopropyl, 2,3-difluorocyclobutyl, 3,4-difluorocyclohexyl, and 3,4- difluoro-5-methylcycloheptyl. The polyorganohydrogensiloxane may be linear, branched, cyclic, resinous, or a combination thereof. Alternatively, the polyorganohydrogensiloxane may be linear or branched. Alternatively, the polyorganohydrogensiloxane may be linear.

[0025] Alternatively, (B) the polyorganohydrogensiloxane, may comprise unit formula (B1): (R93SiO1 / 2)w(R92HSiO1 / 2)x(R92SiO2 / 2)y(R9HSiO2 / 2)z, wherein R9is as described above; subscripts w, x, y, and z are integers representing average numbers of siloxane units per molecule, and subscripts w, x, y, and z have values such that: w is 0, 1, or 2, x is 0, 1, or 2, a quantity (w + x) has an average value of 2; y ≥ 0, z ≥ 0, a quantity (x + z) ≥ 2, and 10,000 ≥ (w + x + y + z) ≥ 2. Alternatively each R9may be independently selected from the group consisting of an alkyl group of 1 to 18 carbon atoms and an aryl group of 6 to 18 carbon atoms. Alternatively, each R9may be methyl or phenyl. Alternatively, each R9in unit formula (B1) may be methyl.

[0026] In unit formula (B1) above, subscript y may have an average value ranging from 0 toz may an average value ranging from 0 to 2,000. Alternatively, subscript y may be 0 to 1,000, alternatively 0 to 500, alternatively 0 to 250, alternatively 0 to 100, alternatively 0 to 50, and alternatively 0 to 25. Alternatively, subscript z may be 0 to 1,000; alternatively 2 to 500, alternatively 2 to 250, alternatively 2 to 100, and alternatively 3 to 50. Alternatively, a quantity (y + z) may be 2 to 1,000, alternatively 3 to 900, and alternatively 4 to 800.

[0027] Polyorganohydrogensiloxanes for starting material B-2) are exemplified by: a) dimethylhydrogensiloxy-terminated polydimethylsiloxane, b) dimethylhydrogensiloxy- terminated poly(dimethylsiloxane / methylhydrogensiloxane), c) dimethylhydrogensiloxy- terminated polymethylhydrogensiloxane, d) trimethylsiloxy-terminated poly(dimethylsiloxane / methylhydrogensiloxane), e) trimethylsiloxy-terminated polymethylhydrogensiloxane, f) a resin consisting essentially of H(CH3)2SiO1 / 2units and SiO4 / 2units, and g) a combination thereof.

[0028] Polyorganohydrogensiloxanes are also commercially available, such as those available from Gelest, Inc. of Morrisville, Pennsylvania, USA, for example, HMS-H271, HMS-071, HMS-993; HMS-301 and HMS-301 R, HMS-031, HMS-991, HMS-992, HMS-993, HMS-082, HMS-151, HMS-013, HMS-053, HAM-301, HPM-502, and HMS-HM271. Other polyorganohydrogensiloxanes include DOWSIL™ 6-3570 Polymer, DOWSIL™ SH1107 Fluid, SYL-OFF™ 7048 Crosslinker, SYL-OFF™ 7678 Crosslinker, SYL-OFF™ 7682-000 Crosslinker, SYL-OFF™ 7682-055 Crosslinker, SYL-OFF™ SL 8 Crosslinker, SYL-OFF™ SL 9 Crosslinker, SYL-OFF™ SL 11 Crosslinker, SYL-OFF™ SL 12 Crosslinker, XIAMETER™ MHX-11007 Fluid, and XIAMETER™ OFS-5057 Fluid, all of which are commercially available from The Dow Chemical Company of Midland, Michigan, USA. Methods of preparing linear, branched, and cyclic organohydrogenpolysiloxanes suitable for use herein, such as hydrolysis and condensation of organohalosilanes, are well known in the art, see for example US Patent 3957713 to Jeram et al. and US Patent 4329273 to Hardman, et al. Methods of preparing organohydrogenpolysiloxane resins suitable for use herein are exemplified, e.g., in US Patents 5310843; 4370358; and 4707531. And, US Patent 2823218 to Speier, et al., discloses organohydrogensiloxane oligomers and linear polymers, e.g., 1,1,3,3-tetramethyldisiloxane; 1,1,1,3,3-pentamethyldisiloxane; 1,1,1,3,5,5,5-heptamethyltrisiloxane; bis-trimethylsiloxy- terminated polymethylhydrogensiloxane homopolymer; bis-trimethylsiloxy-terminated poly(dimethyl / methylhydrogen)siloxane copolymer; and cyclic polymethylhydrogensiloxanes.

[0029] Starting material (A) the aldehyde-functional polyorganosiloxane and starting material (B) the polyorganohydrogensiloxane are selected such that in the curable polyorganosiloxanethe aldehyde-functional polyorganosiloxane has only two silicon bondedaldehyde-functional groups per molecule, then the polyorganohydrogensiloxane has at least three silicon bonded hydrogen atoms per molecule; and when the polyorganohydrogensiloxane has only two silicon bonded hydrogen atoms per molecule, then the aldehyde-functional polyorganosiloxane has at least three silicon bonded aldehyde-functional groups per molecule.

[0030] Amounts of and selections of starting materials (A) and (B) are provided to make the composition capable of curing. The amounts and selections of starting materials (A) and (B) may be such that a molar ratio of silicon bonded hydrogen atoms in starting material (B) to silicon bonded aldehyde groups in starting material (A) (the “SiH / Aldehyde ratio”) is 1:1 to 1:10, alternatively 1: 1.05 to 1:10. Without wishing to be bound by theory, it is thought that when the SiH / Aldehyde ratio is 1 : > 1, then this minimizes the amount of unreacted silicon bonded hydrogen atoms after curing.

[0031] Starting material (C) is a catalyst composition, which catalyzes hydrosilylation reaction of the aldehyde groups and silicon bonded hydrogen atoms. The catalyst composition comprises starting material (i) the halogenated arylborane Lewis acid. The halogenated arylborane Lewis Acid has general formula BR1R2R3, wherein R1, R2, and R3are each independently selected from the group consisting of halogen atoms, aryl groups, and halogenated aryl groups, with the proviso that at least one of R1, R2, and R3is a halogenated aryl group; alternatively at least two of R1, R2, and R3are halogenated aryl groups; and alterantively all three of R1, R2, and R3may be halogenated aryl groups. Suitable halogen atoms include Cl and F, alternatively F. Suitable aryl groups include phenyl, tolyl, and xylyl. Suitable halogenated aryl groups are exemplified by the aryl groups described above, wherein at least one hydrogen atom is replaced by a halogen atom. The halogenated aryl groups are exemplified by groups of empirical formula (C6HaX(5-a)), wherein subscript a is an integer with a value of 0, 1, 2, 3, or 4; and each X is selected from the group consisting of a halogen atom and a halogenated alkyl group. The halogen atom for X may be F, Cl, or I; alternatively F or Cl, and alternatively F. The halogenated alkyl group may have empirical formula (CbX’(2b+1)), where X’ is a halogen atom as described above and subscript b is an integer with a value of 1 to 9, alternatively 1 to 4, and alternatively 1 to 3. Alternatively, the halogenated aryl group may be selected from the group consisting of:), 2), . Alternatively, the halogenated arylborane Lewis acid maysuch as B(C6F5)3, which is commercially available from, e.g., Sigma-Aldrich, Inc. of St. Louis, Missouri, USA. Halogenated arylboranes may be prepared by known methods, such as those disclosed in PCT Patent Application Publication WO2019 / 055740 by varying appropriate starting materials.

[0032] Starting material (ii) is an optional inhibitor for (i) the halogenated arylborane Lewis acid. Starting material (ii) comprises a Lewis basic amine. The Lewis basic amine may be aa secondary amine, or a tertiary amine. The Lewis basic amine may haveformula: R4R5R6N, wherein R4, R5, and R6are each independently selected from the group consisting of H and an alkyl groups of 1 to 6 carbon atoms. Alternatively, each R4, R5, and R6may be alkyl, alternatively ethyl. Examples of suitable Lewis basic amines include trialkyl amines exemplified by triethylamine, tripropylamine, tributylamine, tripentylamine, and trihexylamine, all of which are known in the art and are commercially available. When present, the amount of (ii) the Lewis basic amine is sufficient to provide at least 1.0 molar equivalents of amine with respect to (i) the halogenated arylborane Lewis acid. Alternatively, the amount of of (ii) the Lewis basic amine may be sufficient to provide ≥ 1.0 molar equivalents, alternatively > 1.0 molar equivalents, and alternatively at least 1.05 molar equivalents, of amine with respect to (i) the halogenated arylborane Lewis acid. At the same time, the amount of (ii) the Lewis basic amine may be sufficient to provide up to 1.5 molar equivalents, alternatively up to 1.25 molar equivalents, of amine with respect to (i) the halogenated arylborane Lewis acid. Alternatively, when the Lewis basic amine is used, the amount may be 1.0 to 1.5, alternatively 1.05 to 1.5, molar equivalents of Lewis basic amine with respect to borane in (i) the halogenated arylborane Lewis acid.

[0033] Starting material (iii) is a solvent that may optionally be used in preparation of (C) the catalyst composition. When (ii) the Lewis basic amine is used, the catalyst composition may be prepared by a process comprising combining (i) the halogenated arylborane Lewis acid and (ii) the Lewis basic amine. Combining may be performed by any convenient means, such as dissolving the (i) the halogenated arylborane Lewis acid and (ii) the Lewis basic amine in (iii) the solvent with mixing. Mixing may be performed by any convenient means, such as mixing in a batch vessel at room temperature or with heating, e.g., to a temperature less than boiling point of the solvent, when used. Without wishing to be bound by theory, it is thought that (i) the halogenated arylborane Lewis acid and (ii) the Lewis basic amine may form a physical mixture or a complex, or a combination thereof. The solvent may optionally removed after combining (i) the halogenated arylborane Lewis acid and (ii) the Lewis basic amine. For example, all or a portion of the solvent may be removed by evaporation or stripping with heat and optionally reduced pressure.

[0034] Starting material (iii), the solvent, may be selected from the group consisting ofaromatic hydrocarbons, aliphatic hydrocarbons, halogenated aromatic hydrocarbons, halogenated aliphatic hydrocarbons, or a combination thereof. The aromatic hydrocarbon may be benzene, toluene, xylene, or a combination thereof. The aliphatic hydrocarbon may be heptane, hexane, octane, or a combination thereof. The halogenated hydrocarbons may be anyabove aromatic hydrocarbons and / or aliphatic hydrocarbons, wherein at least one hydrogen atom is replaced with a halogen atom, such as Cl or F. Alternatively, the solvent may be selected from the group consisting of aromatic hydrocarbons, aliphatic hydrocarbons, and a combination thereof. The amount of solvent is not critical, and may be sufficient to dissolve (i) the halogenated arylborane Lewis acid and (ii) the Lewis basic amine.

[0035] The (C) catalyst composition comprising: (i) the halogenated arylborane Lewis acid and optionally (ii) the Lewis basic amine, described above, may be free of conventional hydrosilylation reaction catalysts (which include platinum). The catalyst may also be free of conventional hydrosilylation reaction inhibitors such as those described, for example, in US Patent 10774217. Without wishing to be bound by theory, it is thought that conventional hydrosilylation reaction inhibitors, such as alkyne alcohols (or acetylenic alcohols), cycloalkenylsiloxanes, ketones, ene-yne compounds, triazoles, phosphines, mercaptans, hydrazines, sulphoxides, phosphates, nitriles, hydroperoxides, amines (other than (ii) the Lewis basic amine described for use in (C) the catalyst composition), ethylenically unsaturated isocyanates, fumarates, maleates, and alkenes are not needed, e.g., to control bathlife when the catalyst described above is used in a curable polyorganosiloxane composition suitable for making a release coating instead of a conventional platinum hydrosilylation reaction catalyst for a composition including an alkenyl-functional polyorganosiloxane and a polyorganohydrogensiloxane.

[0036] In the curable polyorganosiloxane composition, starting material (D) the antioxidant, introduced above, comprises a phenolic antioxidant, which is optional. Suitable antioxidants include phenolic antioxidants and combinations of phenolic antioxidants with stabilizers. Phenolic antioxidants include fully sterically hindered phenols and partially hindered phenols. Suitable phenolic antioxidants are commercially available and are exemplified by those with the tradename IRGANOX™ from BASF Corporation of Florham Park, New Jersey, USA. These include 1,3,5-trimethyl-2,4,6-tris(3,5-di-tert-butyl-4-hydroxybenzyl)benzene (IRGANOX™ 1330); pentaerythritol tetrakis(3-(3,5-di-t-butyl-4-hydroxyphenyl)propionate) (IRGANOX™ 1010). Others include octadecyl 3-(3,5-di-tert-butyl-4-hydroxyphenyl)propionate; butylated hydroxytoluene (BHT); and 2,5,7,8-tetramethyl-2-(4,8,12-trimethyltridecyl)chroman-6-ol (which is also known as (±)-α-Tocopherol or vitamin E). Antioxidants are known in the art and are commercially available from various sources, including Sigma-Aldrich, Inc. The amount of (D) the antioxidant depends on various factors including the type of antioxidant selected and the aldehyde content of starting material (A), however, when used the amount of antioxidant may be at least 500 ppm, alternatively at least 1,000 ppm; while at the same time the amount ofbe up to 10,000 ppm, alternatively up to 5,000 ppm, and alternatively up to2,500 ppm; and alternatively 1,000 ppm to 5,000 ppm, each based on weight of (A) the aldehyde-functional polyorganosiloxane. Without wishing to be bound by theory, it is thought that the antioxidant may minimize or prevent oxidation of the aldehyde groups of starting material (A), when exposed to air, but if starting material (A), and / or the composition, is stored under high purity argon or nitrogen, the oxidation will also be avoided even without the antioxidant.

[0037] The curable polyorganosiloxane composition described herein may comprise starting materials (A), (B), and (C), and optionally (D). Alternatively, the curable polyorganosiloxane may consist essentially of starting materials (A), (B), and (C), and optionally (D). Alternatively, the curable polyorganosiloxane composition may consist of starting materials (A), (B), and (C), and optionally (D). The amounts of starting materials (A), (B), (C) and (D) in the composition depend on various factors including the selection and amount of each starting material, the aldehyde group content of starting material (A), the silicon bonded hydrogen atom content of starting material (B), and whether (ii) the Lewis basic amine is used in starting material (C). However, the amounts may be: 40% to 90%, alternatively 50% to 85%, and alternatively 78.6% to 83.3% of (A) the aldehyde-functional polyorganosiloxane; 2% to 30%, alternatively 5% to 25%, and alternatively 14.3% to 20.1% of (B) the polyorganohydrogensiloxane; 0.01% to 5%, alternatively 0.01% to 1%, alternatively 0.05% to 0.1%, and alternatively 0.06% to 0.07% of (C) the catalyst composition; and 0.002% to 5%, alternatively 0.01% to 1%, and alternatively 0.1% to 0.5% of (D) the antioxidant. When the curable polyorganosiloxane composition consists of starting materials (A), (B), (C), and (D), the values listed above will total 100%. Alternatively, in addition to starting materials (A), (B), (C), and (D), the composition may further comprise an optional additional starting material.

[0038] The curable polyorganosiloxane composition may optionally further comprise an additional starting material. The type and amount of additional starting material will depend on various factors including the end use for the curable polyorganosiloxane composition and the cured product thereof. For example, the curable polyorganosiloxane composition may optionally further comprise a filler such as talc, silica (e.g., ground and / or fumed), and / or calcium carbonate. Alternatively, when the curable polyorganosiloxane composition will be used to prepare a release coating, the additional starting material may be selected from the group consisting of (E) a release modifier, (F) an anchorage additive, (G) a solvent, (H) an anti-mist additive, (I) a hydrosilylation reaction inhibitor, and a combination of two or more thereof.

[0039] The curable polyorganosiloxane composition may comprise (E) a release modifier tothe level of release force (the adhesive force between the release coating andan adherend thereto, such as a label including a pressure sensitive adhesive). Compositions that cure to form release coatings having the required release force can be formulated from a modifier-free curable polyorganosiloxane composition by adjusting the level of modifier. Examples of suitable release modifiers include trimethylsiloxy-terminated dimethyl, phenylmethylsiloxanes. Alternatively, the release modifier may be a condensation reaction product of an organopolysiloxane resin having hydroxyl or alkoxy groups and a diorganopolysiloxane with at least one hydroxyl or hydrolyzable group. If used, (E) the release modifier can, for example, be used at 0 to 85 parts by weight, alternatively 25 to 85 parts, per 100 parts of starting material (A) the aldehyde-functional polyorganosiloxane. Examples of suitable release modifiers are disclosed, for example, in US Patent 8933177 and US Patent Application Publication 20160053056.

[0040] Starting material (F) is an anchorage additive. Suitable anchorage additives are exemplified by a physical blend of a polyorganosiloxane having at least one aldehyde group and at least one hydrolyzable group per molecule (which may be prepared via the hydroformylation process described above) and an epoxy-functional alkoxysilane (e.g., glycidoxypropyltrimethoxysilane), which is commercially available. The exact amount of anchorage additive depends on various factors including the type of substrate and whether a primer or other surface treatment is used on the substrate prior to application of the curable polyorganosiloxane composition, however, the amount of anchorage additive in the curable polyorganosiloxane composition may be 0 to 2 parts by weight, per 100 parts by weight of starting material (A). Alternatively, the amount of anchorage additive may be 0.01 to 2 parts by weight, per 100 parts by weight of starting material (A), the aldehyde-functional polyorganosiloxane.

[0041] Starting material (G) is an optional solvent, which may be as described above for use in forming (C) the catalyst composition. The amount of solvent used in the curable polyorganosiloxane composition as an optional starting material will depend on various factors including the type of solvent selected and the amount and type of other starting materials selected for the curable polyorganosiloxane composition. However, the amount of solvent may be 0% to 99%, alternatively 2% to 50%, based on the weight of all starting materials in the composition. The solvent may be added during preparation of (C) the catalyst composition and / or the curable polyorganosiloxane composition, for example, to aid mixing and delivery of one or more of the starting materials. All or a portion of the solvent may optionally be removed after (C) the catalyst composition, and / or after the curable polyorganosiloxane composition, is

[0042] Starting material (H) is an anti-mist additive (also called a high speed process aid) that may be added to the curable polyorganosiloxane composition to reduce or suppress silicone mist formation in coating processes, particularly with high speed coating equipment. The anti-mist additive may be a reaction product of an organohydrogensilicon compound, an oxyalkylene compound or an organoalkenylsiloxane with at least three silicon bonded alkenyl groups per molecule, and a suitable catalyst. Suitable anti-mist additives for starting material (H) are disclosed, for example, in US Patent Application Publication 20110287267; US Patent 8722153; US Patent 6586535; and US Patent 5625023. When prepared via conventional hydrosilylation reaction, the catalyst may optionally be removed before use in the curable polyorganosiloxane composition described herein, using the techniques described above for removal of the hydroformylation catalyst from (A) the aldehyde-functional polyorganosiloxane. Suitable anti- mits additives are commercially available, for example, SYL-OFF™ 7137 High Speed Crosslinker, and SYL-OFF™ 7138 High Speed Crosslinker are available from The Dow Chemical Company.

[0043] The amount of anti-mist additive will depend on various factors including the amounts and types of other starting materials selected for the curable polyorganosiloxane composition. However, the amount of anti-mist additive may be 0% to 10%, alternatively 0.1% to 3%, based on the weight of all starting materials in the composition.

[0044] Other optional starting materials which may also be added to curable polyorganosiloxane compositions described herein include, for example, reactive diluents, fragrances, preservatives, colorants (e.g., dyes and pigments) and fillers, for example, silica, quartz or chalk.

[0045] Alternatively, the curable polyorganosiloxane composition may be free of filler or contain only a limited amount of filler, such as 0 to 30%, for example, when the curable polyorganosiloxane composition will be used to prepare a release coating. Without wishing to be bound by theory it is thought that fillers can agglomerate or otherwise stick to the coater equipment used to apply the curable polyorganosiloxane composition to a substrate and / or fillers can hinder optical properties, for example transparency, of a release coating and of the release liner formed therewith, if optical transparency is desired. The fillers may be prejudicial to the adherence of an adherend, such as a pressure sensitive adhesive coated substrate (e.g., label or tape).

[0046] When selecting starting materials for the curable polyorganosiloxane composition, there may be overlap between types of starting materials because certain starting materialsmay have more than one function. Certain particulates may be useful as fillersand as pigments, and even as flame retardants, e.g., carbon black. Certain anti-mist additives which contain silicon bonded hydrogen atoms may also function as crosslinkers. When adding additional starting materials to the curable polyorganosiloxane composition, the additional starting materials are distinct from starting materials (A) to (D) and from one another. When additional starting materials contain aldehyde groups and / or silicon bonded hydrogen atoms, these may be taken into account when calculating the SiH / Aldehyde ratio, described above.

[0047] The curable polyorganosiloxane composition may be free from fluoroorganosilicone compounds. It is believed that, during the cure, a fluoroorganosilicone compound, because of its low surface tension, will rapidly migrate to the interface of a curable polyorganosiloxane composition and a substrate, for example a curable polyorganosiloxane composition / PET film interface, and prevent adherence of the resulting coating (prepared by curing the curable polyorganosiloxane composition) to the substrate by making a fluorine containing barrier. By making a barrier, the fluoroorganosilicone compound prevents any component from reacting at the interface. Moreover, fluoroorganosilicone compounds are usually expensive.

[0048] The curable polyorganosiloxane composition may be free of platinum. The curable polyorganosiloxane composition may also be free of conventional hydrosilylation reaction inhibitors such as those described, for example, in US Patent 10774217. Without wishing to be bound by theory, it is thought that conventional hydrosilylation reaction inhibitors, such as alkyne alcohols (or acetylenic alcohols), cycloalkenylsiloxanes, ketones, ene-yne compounds, triazoles, phosphines, mercaptans, hydrazines, sulphoxides, phosphates, nitriles, hydroperoxides, amines (i.e., other than (ii) the Lewis basic amine described above in (C) the catalyst composition), ethylenically unsaturated isocyanates, fumarates, maleates, and alkenes are not needed, e.g., to control working time (bulk bathlife and / or thin film bathlife) when the curable polyorganosiloxane composition is used to prepare a release coating. The curable polyorganosiloxane composition may be prepared without the intentional addition of conventional hydrosilylation reaction catalysts containing platinum group metals. However, one skilled in the art would recognize that the curable polyorganosiloxane composition described herein may contain residual catalyst, e.g., rhodium / ligand complex may be present when the aldehyde-functional polyorganosiloxane is prepared via hydroformylation reaction and the aldehyde-functional polyorganosiloxane is not treated with an adsorbent to remove such residual catalyst before use in the method of preparing the curable polyorganosiloxane composition.

[0049] A method of preparing the curable polyorganosiloxane composition described above is also provided. The method comprises combining starting materials comprising (A) thepolyorganosiloxane, (B) the polyorganohydrogensiloxane, and (C) thecatalyst composition, and, when present (D) the antioxidant to give the curable polyorganosiloxane composition. When one or more of the other optional additional starting materials described above are used to make the curable polyorganosiloxane composition, the method further comprises combining such starting materials along with starting materials (A), (B), and (C), and when present (D).

[0050] The starting materials may be combined via any suitable technique (e.g., mixing) in any suitable equipment (e.g., batch vessel with an agitator or baffles) and in any order of addition. However, (A) the aldehyde-functional polyorganosiloxane and (D) the antioxidant may be combined separately, and later combined with the other starting materials of the curable polyorganosiloxane composition. Without wishing to be bound by theory, it is thought that (D) the antioxidant may prevent or minimize oxidation of the aldehyde groups into carboxylic acids before use and cure of the curable polyorganosiloxane composition. Alternatively, when (ii) the Lewis basic amine is used, (C) the catalyst composition may be prepared by a method comprising combining starting materials comprising (C)(i) the halogenated arylborane Lewis acid and (C)(ii) the Lewis basic amine (as described above) before combining starting material (C) with other starting materials. Alternatively, in the absence of (C)(ii) the Lewis basic amine, the starting materials of the curable polyorganosiloxane composition may begin to react in the presence of the (C)(i) the halogenated arylborane Lewis acid, once combined. Therefore the starting materials may be combined shortly before use, e.g., when a one part curable polyorganosiloxane composition is desired.

[0051] Alternatively, the curable polyorganosiloxane composition can be prepared as a multiple part composition in which (B) the polyorganohydrogensiloxane and (C) the catalyst composition are stored in separate parts, which are combined together, e.g., by mixing, when ready for use. For example, a two part composition may be prepared by combining starting materials comprising a first portion of (A) the aldehyde-functional polyorganosiloxane and (C) the catalyst composition as a first mixture, and combining starting materials comprising (B) the polyorganohydrogensiloxane and a second portion of (A) the aldehyde-functional polyorganosiloxane as a second mixture. The first mixture and the second mixture are each not reactive until combined to give the curable polyorganosiloxane composition. One or more of the optional additional starting materials may be included in the first mixture, the second mixture or both. The first mixture and the second mixture may be combined by mixing in a weight ratio of 10:1 to 1:10 (first mixture : second mixture), alternatively 10:1 to 1:1, and alternatively 10:1 to > 1:1, alternatively 5:1 to 1:1, and alternatively 2:1 to 1:1, such that excess silicon bondedare not present after curing the curable polyorganosiloxane composition.

[0052] The present invention also provides method of using the curable polyorganosiloxane composition for forming a film. The film may alternatively be referred to as a coating, as the film is formed on a substrate. The film may be peelable from the substrate, or may be chemically and / or physically bonded to the substrate. The method of forming the film comprises applying the curable polyorganosiloxane composition on a substrate to give a deposit. The method further comprises forming the film on the substrate from the deposit.

[0053] The substrate is not limited and may be any substrate depending on an end use application of the film. Examples of suitable substrates include cellulosic materials, such as paper, cardboard and wood; metals, such as aluminum, iron, steel, or an alloy thereof; siliceous materials, such as ceramics, glass and concrete. The substrate may also be a plastic substrate. Specific examples of suitable plastic substrates include polyamides (PA); polyesters such as polyethylene terephthalates (PET), polybutylene terephthalates (PBT), polytrimethylene terephthalates (PTT), polyethylene naphthalates (PEN), liquid crystalline polyesters, and combinations thereof; polyolefins such as polyethylenes (PE), polypropylenes (PP), polybutylenes, poly(ethylene / octene) copolymers, and combinations thereof; styrenic resins; polyoxymethylenes (POM); polycarbonates (PC); polymethylenemethacrylates (PMMA); polyvinyl chlorides (PVC); polyphenylene sulfides (PPS); polyphenylene ethers (PPE); polyimides (PI); polyamideimides (PAI); polyetherimides (PEI); polysulfones (PSU); polyethersulfones; polyketones (PK); polyetherketones (PEK); polyvinyl alcohols (PVA); polyetheretherketones (PEEK); polyetherketoneketones (PEKK); polyarylates (PAR); polyethernitriles (PEN); phenolic resins; phenoxy resins; celluloses such as triacetylcellulose, diacetylcellulose, cellophane, and combinations thereof; fluorinated resins, such as polytetrafluoroethylenes; thermoplastic elastomers, such as polystyrene types, polyolefin types, polyurethane types, polyester types, polyamide types, polybutadiene types, polyisoprene types, fluoro types, and combinations thereof.

[0054] In view of the controlled release properties of the film, the substrate may be selected based on desired end use applications involving pressure sensitive adhesives. For example, pressure sensitive adhesives may be controllably released from the film, and thus the film may be utilized for release liners for pressure sensitive adhesives. The substrate may be flexible. However, the substrate may alternatively be rigid, or a combination of rigid and flexible. The film formed on the substrate may be continuous or discontinuous.

[0055] The curable polyorganosiloxane composition may be applied to the substrate via a wet coating technique. For example, the composition may be applied by i) spin coating, ii) brushcoating, iv) spray coating, v) dip coating, vi) roll coating, vii) flow coating,viii) slot coating, ix) gravure coating, x) doctor blade coating, xi) screen printing, or xii) a combination of two or more thereof. Alternatively, when the substrate is flexible, e.g., paper, the wet coating technique may utilize a trailing blade coater, kiss rolls, gravure rolls, and / or offset printing rolls. Alternatively, when the curable polyorganosiloxane composition will be used to prepare a release coating, the curable polyorganosiloxane composition may be applied to the substrate by any convenient means such as spraying, doctor blade, dipping, screen printing or by a roll coater, e.g., an offset web coater, kiss coater or etched cylinder coater.

[0056] The amount of the curable polyorganosiloxane composition applied to the substrate depends on various factors including whether a solvent is present and the thickness of the film desired on the substrate, however, for a release coating application, the amount may be 0.1 gram to 2 grams per square meter of surface of the substrate.

[0057] The deposit formed by applying the curable polyorganosiloxane composition is typically an uncured film. The uncured film may have undergone at least partial curing, but remains curable upon application of a curing condition (e.g., heating the uncured film).

[0058] Forming the film from the deposit generally comprises curing the curable polyorganosiloxane composition. The curable polyorganosiloxane composition may be cured at RT, alternatively at an elevated temperature for a period of time. The elevated temperature may be 50 °C to 300 °C, alternatively 100 °C to 250 °C, alternatively 150 °C to 200 °C. The period of time is typically sufficient to effect curing, i.e., cross-linking, of the curable polyorganosiloxane composition. The period of time depends on various factors including the temperature selected, the desired film thickness, and the presence or absence of any solvent in the curable polyorganosiloxane composition, and the dimensions of the deposit. For example, the period of time may be less than 1 minute, alternatively less than 30 seconds, alternatively less than 15 seconds, alternatively less than 10 seconds, alternatively less than 5 seconds. Alternatively, the period of time may be from greater than 0 to 8 hours, alternatively from greater than 0 to 2 hours, alternatively from greater than 0 to 1 hour, alternatively from greater than 0 to 30 minutes, alternatively from greater than 0 to 15 minutes, alternatively from greater than 0 to 10 minutes, alternatively from greater than 0 to 5 minutes, alternatively from greater than 0 to 2 minutes.

[0059] Curing the curable polyorganosiloxane composition may have a dwell time of 0.1 second to 50 seconds; alternatively 1 second to 10 seconds; and alternatively 0.5 second to 30 seconds. Dwell time selected may depend on various factors including the substrate selection, temperature selected, and line speed. Dwell time, as used herein, refers to the time during whichcomposition, or the deposit, is subjected to the elevated temperature. Dwell time is distinguished from cure time, as there may be ongoing curing even after the curable polyorganosiloxane composition, deposit, or partially cured reaction intermediary thereof is no longer subjected to the elevated temperature, which elevated temperature may be employed to initiate curing. Alternatively, the coated substrate may be prepared on a conveyor belt in an oven, and the dwell time may be calculated by dividing a length of the oven (e.g., in meters) by a line speed of the conveyor belt (e.g., in meters / sec).

[0060] The period of time may be broken down into cure iterations, e.g., a first-cure and a post-cure, with the first-cure being, for example, one hour and the post cure being, for example, three hours. The elevated temperature may be independently selected from any temperature above room temperature in such iterations, and may be the same in each iteration.

[0061] The source of heat may be any suitable source. For example, the substrate may be heated such that the curable polyorganosiloxane composition cures upon contact with the substrate. Alternatively, the substrate and deposit may be placed in or passed through an oven.

[0062] Depending on a thickness and other dimensions of the deposit and film, the film could also be formed via an iterative process. For example, a first deposit may be formed and subjected to a first elevated temperature for a first period of time to give a partially or fully cured first deposit. Then, a second deposit may be disposed on the first deposit and subjected to a second elevated temperature for a second period of time to give a partially or fully cured second deposit. The second deposit may also further cure during exposure to the second elevated temperature for the second period of time. A third deposit may be disposed on the second deposit and subjected to a third elevated temperature for a third period of time to give a third partially or fully cured deposit. The second deposit may also further cure during exposure to the second elevated temperature for the second period of time. This process may be repeated, for example, from 1 to 50 times, as desired, until a composite with a desired thickness of the cured product of the partially or fully cured polyorganosiloxane composition (e.g., a release coating) on the substrate is achieved. A composite of partially cured layers may be subjected to a final post-cure, e.g., at the elevated temperature and period of time above. Each elevated temperature and period of time may be independently selected and may be the same as or different from one another. When the composite is formed via the iterative process, each deposit may also be independently selected and may differ in terms of starting materials selected in the curable polyorganosiloxane composition, their amounts, or both. Alternatively still, each iterative layer may be fully cured, rather than only being partially cured, in such an iterative process.

[0063] As described above, the deposit may comprise a wet film. Alternatively, the iterativewet-on-wet, depending on a cure state of the partially cured layer. Alternatively, the iterative process may be wet-on-dry.

[0064] The resulting coated substrate, which comprises the film formed from the curable polyorganosiloxane composition on the substrate, may have varying dimensions, including relative thicknesses of the film and the substrate. The film has a thickness that may vary depending upon its end use application. The film may have a thickness of greater than 0 to 4,000 µm, alternatively greater than 0 to 3,000 µm, alternatively greater than 0 to 2,000 µm, alternatively greater than 0 to 1,000 µm, alternatively greater than 0 to 500 µm, alternatively greater than 0 to 250 µm. However, other thicknesses are contemplated, e.g., 0.1 to 200 µm. For example, the thickness of the film may be 0.2 to 175 µm; alternatively 0.5 to 150 µm; alternatively 0.75 to 100 µm; alternatively 1 to 75 µm; alternatively 2 to 60 µm; alternatively 3 to 50 µm; and alternatively 4 to 40 µm. Alternatively, when the substrate is plastic, the film may have a thickness of greater than 0 to 200, alternatively greater than 0 to 150 µm, and alternatively greater than 0 to 100 µm.

[0065] Optionally, the film may be subjected to further processing depending upon its end use application. For example, the film may be subjected to oxide deposition (e.g., SiO2 deposition), resist deposition and patterning, etching, chemical, corona, or plasma stripping, metallization, or metal deposition. Such further processing techniques are generally known. Such deposition may be chemical vapor deposition (including low-pressure chemical vapor deposition, plasma- enhanced chemical vapor deposition, and plasma-assisted chemical vapor deposition), physical vapor deposition, or other vacuum deposition techniques. Many such further processing techniques involve elevated temperatures, particularly vacuum deposition, for which the film is well suited in view of its excellent thermal stability. Depending on an end use of the film, however, the film may be utilized with such further processing.

[0066] The coated substrate may be utilized in diverse end use applications. For example, the coated substrate may be utilized in coating applications, packaging applications, adhesive applications, fiber applications, fabric or textile applications, construction applications, transportation applications, electronics applications, or electrical applications. However, the curable polyorganosiloxane composition may be utilized in end use applications other than preparing the coated substrate, e.g., in the preparation of articles, such as silicone rubbers.

[0067] Alternatively, the coated substrate may be utilized as a release liner, e.g., for a tape or adhesive, including any pressure-sensitive adhesives, including acrylic resin-type pressure- sensitive adhesives, rubber-type pressure-sensitive adhesives, and silicone-type pressure- sensitive adhesives, as well as acrylic resin-type adhesives, synthetic rubber-type adhesives,epoxy resin-type adhesives, and polyurethane-type adhesives. Eachmajor surface of the substrate may having a film disposed thereon for double sided tapes or adhesives.

[0068] To prepare a release liner, the curable polyorganosiloxane composition of the invention can be applied to any substrate, such as those described above. Alternatively, the curable polyorganosiloxane composition, such as that including one or more of the optional additional starting materials (E) to (H), may be applied to polymer film substrates, for example polyester, particularly polyethylene terephthalate (PET), polyethylene, polypropylene, or polystyrene films. The curable polyorganosiloxane composition can alternatively be applied to a paper substrate, including plastic coated paper, for example paper coated with polyethylene, glassine, super calender paper, or clay coated kraft. The curable polyorganosiloxane composition can alternatively be applied to a metal foil substrate, for example aluminum foil.

[0069] Optionally, the method for preparing the coated substrate may further comprise treating the substrate before applying the curable polyorganosiloxane composition on the substrate. Treating the substrate may be performed by any convenient means such as a plasma treatment or a corona discharge treatment. Alternatively, the substrate may be treated by applying a primer. Anchorage of the release coating may be improved if the substrate is treated before forming the film thereon from the curable polyorganosiloxane composition.

[0070] When the curable polyorganosiloxane composition includes (G) the solvent, the method may further comprise removing the solvent before or during curing the composition, which may be performed by any conventional means, such as heating at 50 °C to 100 °C for a time sufficient to remove all or a portion of (G) the solvent.

[0071] Under production coater conditions to prepare a release coating on a substrate, cure can be effected in a residence time of 1 second to 6 seconds, alternatively 1.5 seconds to 3 seconds, at an air temperature of 120 °C to 150 °C. Heating can be performed in an oven, e.g., an air circulation oven or tunnel furnace or by passing the coated film around heated cylinders.

[0072] Optionally, an adhesive may be laminated on the film formed from the deposit. The adhesive may be any adhesive, e.g., an acrylate-based adhesive, or a silicone-based adhesive. EXAMPLES

[0073] The following examples are provided to illustrate the invention to one skilled in the art and are not to be construed as limiting the scope of the invention set forth in the claims. The starting materials used in these examples are summarized below in Table 1. Table 1 – Starting MaterialsDescription Source h i lf ti l l il nt s ce n s ce n nDescription Source t l t, where C2H4CHO represents a propyl aldehyde group was prepared as described in PCT Publication WO2022081444 via hydroformylation of Polymer 1 using a rhodium bisphosphite ligand catalyst. The resulting Q-branched propyl aldehyde-functional polyorganosiloxane was divided into samples. To make Aldehyde Polymer 2 in Table 1, 1000 ppm of Antioxidant 1 was combined with a sample of the Q-branched propyl aldehyde-functional polyorganosiloxane. To make Aldehyde Polymer 4 in Table 1, 5000 ppm of Antioxidant 2 was combined with another sample of the Q-branched propyl aldehyde-functional polyorganosiloxane. To make Aldehyde Polymer 5 in Table 1, 1000 ppm of Antioxidant 2 was combined with another sample of the Q- branched propyl aldehyde-functional polyorganosiloxane.

[0075] To carbon treat a sample of Q-branched propyl aldehyde-functional polyorganosiloxane prepared as described in PCT Publication WO2022081444, 15 g of activated carbon and 50 g of toluene were combined, added to the Q-branched propyl aldehyde-functional polyorganosiloxane (which did not contain antioxidant), and the resulting mixture was stirred overnight. After this, the mixture was filtered through a 0.2 micrometer membrane, and the toluene was removed by sparging the sample with nitrogen gas. The resulting carbon treated Q- branched propyl aldehyde-functional polyorganosiloxane was Aldehyde Polymer 1 described above in Table 1. Aldehyde Polymer 2 in Table 1 was prepared by combining Aldehyde Polymer 1 with 1000 ppm of Antioxidant 1.

[0076] In this Reference Example 2, catalyst solution b was prepared as follows: In air, a 30 mL vial was charged with BCF (0.5 g) and toluene (20 g) to afford a colorless solution. In this Reference Example 3, catalyst solution e was prepared as follows: In air, a 30 mL vial was charged with BCF (0.5 g), TEA (0.10 g) and toluene (10 g) to afford a colorless solution.

[0077] In this Reference Example 4, a coating composition bath was prepared by the followingGeneral coating composition bath preparation method: An AldehydePolymer and catalyst solution were mixed via dental mixer at 3500 RPM for 30 s. Then, crosslinker was added and resulting mixture was mixed again on the dental mixer at 3500 RPM for 30s. The selection and amounts of each starting material are summarized below in Table 2. Table 2 – Coating Compositions Starting Material Example -1 Example -2 Example -3 Example -4 Example Example -5 -6 nany triethylamine, and Example-5 did not contain an antioxidant. Examples-1 to -4 each contained triethylamine (inhibitor for the BCF).

[0079] In this Reference Example 5, bathlife was evaluated as follows: a. Bulk bathlife test: The coating composition bath prepared as described above was testedDV2TLV viscometer continuously at certain temperature. Bulk bathlife is the time when the formulated coating composition bath viscosity doubles at the specific temperature. The most important bulk bathlife is the 40˚C bulk bathlife, and it is desirable for bulk bathlife to have a value >4 hours. b. Thin-film bathlife test: The coating composition was coated via 2 mil Bird Bar on a 2 mil thick polyethylene terephthalate (PET) film on a flat platform. Thin film bathlife is the time when the 2 mil thick coating film gelled at room temperature. It is desirable for the thin-film bathlife to have a value >40 mins. Table 3 – Bathlife Test Results Sample / Example Example Example Example Example Example Property -1 -2 -3 -4 -5 -6 y d dunc ona po yorganos oxane w an a sor en , suc as car on ac , remove a or at least a portion of the hydroformylation reaction catalyst, which contained rhodium. In Example-2, the aldehyde-functional polyorganosiloxane was treated with carbon black, but the aldehyde- functional polyorganosiloxanes used in Example-1, Example-3, Example-4, and Example-5 were not treated with carbon black before use. The data in the table above suggest that treatment with the adsorbent may lengthen bulk bathlife of the curable polyorganosiloxane composition. Thin film bathlife of Example-5 was not tested because bulk bathlife was short. Without wishing to be bound by theory, it is thought that Example-1, Example-2, Example-3, and Example-4 would be suitable to use for a release coating application because bulk bathlife and thin film bathlife were sufficient for use in conventional release coating equipment. Example-6 contained antioxidant, but did not contain triethylamine. Example-6 cured quickly, so quickly that it was not tested for thin film bathlife or bulk bathlife. Without wishing to be bound by theory, it is thought that Example-5 and Example-6 could be used in applications where fast cure is desirable.

[0081] In this Reference Example 6, Cure Performance: Extractable Percentage was evaluated as follows: Cure performance of a sample composition is evaluated by determining an extractable percent value (extractable %). A sample composition is coated and cured on a substrate (Glassine paper) to form a coated substrate, which is immediately cut into three sample1.375 inch (3.49 cm)) handled only by tweezers to minimize contaminationand / or damage. Each sample disc is analyzed via XRF to determine an initial coat weight (Wis) before being placed in an individual bottle (100-mL, covered with a lid) containing solvent (methyl isobutyl ketone, 40 mL) and allowed to rest on a bench to soak for 30 minutes. Each sample disc is then removed from the bottle, placed coated-side-up on a clean surface (tissue paper) to allow residual solvent to evaporate (without blotting / wiping), and analyzed via XRF to determine a final coat weight (Wfs). The extractable % of each sample is the percent change in coat weight from the solvent soak, i.e., is calculated using the formula: [(Wis- Wfs) / Wi] x 100%). The extractable % indicates the amount of non-cured components of the sample (e.g., non-crosslinked silicone) extractable from the coated substrate, such as a lower extractable % indicates a higher / better cure performance.

[0082] In this Reference Example 7, Cure Performance: Anchorage (ROR%) was evaluated as follows: The anchorage of a coating composition is evaluated via anchorage index, i.e., by determining a percent rub-off resistance (ROR%) value. In particular, a coating composition is coated and cured on a substrate (Glassine paper) to form a coated substrate. Immediately following cure, the coated substrate is cut into two sample discs (die cutter, 1.375 inch (3.49 cm)), which are each analyzed via XRF to determine an initial coat weight (Wia). Each sample disc is then abraded with a felt under load (1.9 kg) using automated abrading equipment, in a method similar to a Taber-type abrasion test (e.g., such as that of ASTM D4060-19, “Standard Test Method for Abrasion Resistance of Organic Coatings by the Taber Abrader”), and subsequently analyzed via XRF to determine a final coat weight (Wfa). The ROR% of each sample is calculated using the formula: [Wfs / Wis] x 100%). The ROR% indicates how strong the coating is anchored to the substrate, such that a higher ROR% indicates a higher / better anchorage the higher the ROR% value the better.

[0083] In this Reference Example 8, a release test procedure was performed as follows: A coated substrate prepared as described above (release liner sheet) was laminated with Tesa 7475 industrial standard tape (25 mm width and 200 mm long). The laminated sheets were aged under weight (20 g / cm2) in a controlled temperature and humidity room (23 °C / 50% relative humidity) for certain time before. Then, the laminated sheets were cut into strips. Strips were tested on IMASS ZPE-1100W at medium to high delamination speed (10, 100, 300 m / min), and tested on IMASS SP-2100 slip / peel tester at low delamination speed (0.3 m / min).180° peeling method was used. Each sample was tested in triplicates.– Test Results (Performance Target < 10 %, lower % extractables is better)Cure Temperature / 165 °C 154 °C 143 °C 132 °C Extractables (%) ble 4 showed that Example-1 containedas not carbon treated) and demonstrated good cure performance (as shown by extractable% < 10%) not only at high cure temperature, but also at the lower temperatures tested. Example-2 contained Aldehyde Polymer 3 (which was carbon treated and which contained antioxidant) also demonstrated good cure performance (as shown by extractable% < 10%) not only at high cure temperature, but also at the lower temperatures tested. Table 5 – Immediate Anchorage Performance Cure Temperature / 165 °C 154 °C 143 °C 132 °C Immediate ROR% ntaining Aldehyde Polymer 2 (whichcontained antioxidant but was not carbon treated) demonstrated good immediate anchorage performance (as shown by ROR% > 80%) not only at high cure temperature, but also at the lower temperatures tested. Example-2 containing Aldehyde Polymer 3 (which was carbon treated and which contained antioxidant) also demonstrated good immediate anchorage performance (as shown by ROR% > 80%) not only at high cure temperature, but also at the lower temperatures tested. Table 6 – Aged Anchorage Performance Cure Temperature / 7 days RT aged 1 month RT aged 3 month RT agedwere cured at 165 °C. Anchorage was tested after aging 7 days at RT, 1 month at RT, and 3 months at RT. Example-1 contained Aldehyde Polymer 2 (which contained antioxidant but was not carbon treated) and demonstrated good aged anchorage performance (as shown by ROR% > 80%) under all conditions tested. Example-2 contained Aldehyde Polymer 3 (which was carboncontained antioxidant) also demonstrated good aged anchorage performance(as shown by ROR% > 80%) under all conditions tested. Table 7 – Release Test Results Delamination speed Sample tested after aging at 7 days RT 0.3 m / min 10 m / min 100 m / min 300 m / minSample tested after aging for 1 month 0.3 m / min 10 m / min 100 m / min 300 m / mine am na on speed Sample tested after aging for 3 months 03 m / min 10 m / min 100 m / min 300 m / minand s ab e re ease orce a a w de range o de am na on speeds even w en aged rom 3 mon s. These examples show the benefit of the antioxidant in the curable polyorganosiloxane compositions used to prepare release coatings described herein. Test Methods

[0088] Viscosity: Viscosity may be measured at 25 °C at 0.1 to 50 RPM on a Brookfield DV-III cone & plate viscometer with #CP-52 spindle, e.g., for polymers (such as certain (B2) alkenyl- functional polyorganosiloxanes) with viscosity of 120 mPa·s to 250,000 mPa·s. One skilled in the art would recognize that as viscosity increases, rotation rate decreases and would be able to select appropriate spindle and rotation rate.

[0089] Problems to be addressed: There is a continuing need in the coatings industry to provide less expensive, platinum free curable polyorganosiloxane coating compositions. There is continuing need in the polyorganosiloxane release coatings industry to provide platinum-free polyorganosiloxane release coating compositions that can cure to form release coatings using conventional equipment.

[0090] The curable polyorganosiloxane composition described herein may be used to form a polyorganosiloxane release coating. Said composition is platinum free, and may provide good bathlife (e.g., thin film bathlife > 8 days at RT and bulk bathlife > 1 hour, when used under the conditions of Reference Example 5, above). The curable polyorganosiloxane compositionprovides the benefit of being able to be applied to substrates and cured usingconventional release coating equipment currently used for hydrosilylation reaction curable release coating compositions that contain an alkenyl-functional polydiorganosiloxane, and a polyorganohydrogensiloxane crosslinker catalyzed with a platinum catalyst; therefore, release coating manufacturers do not need to change their process equipment to use the new curable polyorganosiloxane composition described herein. The release coating prepared by curing said composition provides one or more beneficial properties, namely extractables < 10%, immediate rub off resistance > 80%, aged rub off resistance > 80%, and release performance < 60 g / inch, as tested according to the methods in Reference Examples 6 and 7, described above.

[0091] All amounts, ratios, and percentages herein are by weight, unless otherwise indicated by the context of the specification. The articles ‘a’, ‘an’, and ‘the’ each refer to one or more, unless otherwise indicated by the context of specification. The singular includes the plural unless otherwise indicated by the context of the specification. The SUMMARY and ABSTRACT are hereby incorporated by reference. The amounts of all starting materials in a composition or an emulsion total 100%. The transitional phrases “comprising”, “consisting essentially of”, and “consisting of” are used as described in the Manual of Patent Examining Procedure Ninth Edition, Revision 08.2017, Last Revised January 2018 at section §2111.03 I., II., and III. Any feature or aspect of the invention may be used in combination with any other feature or aspect recited herein. The abbreviations used herein have the definitions in Table 10. Table 10 - Abbreviations Abbreviation Definitions °C de rees Celsius

[0092] In a first embodiment, a curable polyorganosiloxane release coating composition comprises: (A) an aldehyde-functional polyorganosiloxane having, per molecule, at least twosilicon bonded aldehyde-functional groups of formul , wherein G is a divalent hydrocarbon group free of aliphatic unsatur 8 carbon atoms; (B) a polyorganohydrogensiloxane having, per molecule, at least two silicon bonded hydrogen atoms; with the provisos that when the aldehyde-functional polyorganosiloxane has only two silicon bonded aldehyde-functional groups per molecule, then the polyorganohydrogensiloxane has at least three silicon bonded hydrogen atoms per molecule; and when the polyorganohydrogensiloxane has only two silicon bonded hydrogen atoms per molecule, then the aldehyde-functional polyorganosiloxane has at least three silicon bonded aldehyde-functional groups per molecule; and (C) a catalyst composition comprising: (i) a halogenated triarylborane Lewis acid, and (ii) a Lewis basic amine, and optionally (iii) a solvent; and (D) a phenolic antioxidant; and optionally an additional starting material selected from the group consisting of an anchorage additive, a solvent, an anti-mist additive, and a combination thereof.

[0093] In a second embodiment, a method for preparing the release coating composition of the first embodiment comprises: 1) combining starting materials comprising (A) the aldehyde- functional polyorganosiloxane and (D) the antioxidant, thereby forming a first intermediate mixture; 2) combining the first intermediate mixture and a starting material comprising (C) the catalyst composition, thereby forming a second intermediate mixture; 3) combining the second intermediate mixture and a starting material comprising (B) the polyorganohydrogensiloxane, thereby forming a reaction mixture.

[0094] In a third embodiment, in the method of the second embodiment, (C) the catalyst composition is prepared by a method comprising comprising: mixing starting materials comprising (i) the halogenated arylborane Lewis acid, (ii) the Lewis basic amine, and (iii) a solvent before step 2), thereby forming a solution comprising (C) the catalyst composition.

[0095] In a fourth embodiment, the method of the second embodiment or the third embodiment further comprises: treating (A) the aldehyde-functional organosilicon compound with an adsorbent before step 1).

Claims

1. A curable polyorganosiloxane composition comprising: (A) an aldehyde-functional polyorganosiloxane having, per molecule, at least two silicon bonded aldehyde-functional groups of , wherein G is a divalent hydrocarbon group free of aliphatic carbon atoms;(B) a polyorganohydrogensiloxane having, per molecule, at least two silicon bonded hydrogen atoms; with the provisos that when the aldehyde-functional polyorganosiloxane has only two silicon bonded aldehyde- functional groups per molecule, then the polyorganohydrogensiloxane has at least three silicon bonded hydrogen atoms per molecule; and when the polyorganohydrogensiloxane has only two silicon bonded hydrogen atoms per molecule, then the aldehyde-functional polyorganosiloxane has at least three silicon bonded aldehyde-functional groups per molecule; and (C) a catalyst composition comprising: (i) a halogenated arylborane Lewis acid.

2. The composition of claim 1, wherein (A) the aldehyde-functional polyorganosiloxane comprises unit formula: (R73SiO1 / 2)c(R72R8SiO1 / 2)d(R72SiO2 / 2)e(R7R8SiO2 / 2)f(R7SiO2 / 2)g(R8SiO2 / 2)h(SiO4 / 2)i(ZO1 / 2)j; wherein each R7is an independently selected alkyl group of 1 to 12 carbon atoms; each R8is the aldehyde-functional group of , wherein G is as described above;each Z is independently selected from the group consisting of a hydrogen atom and an alkyl group of 1 to 12 carbon atoms; subscripts c, d, e, f, g, h, and i are integers representing average number of units per molecule, and subscripts c, d, e, f, g, h, and i have values such that: c ≥ 0,g ≥ 0, h ≥ 0, a quantity (d + f + h) ≥ 2, i ≥ 0, and 10,000 ≥ (c + d + e + f + g + h + i) ≥ 2, and subscript j has a value such that 1.5 > j / (g + h + i) > 0.

3. The composition of claim 1 or claim 2, wherein (A) the aldehyde-functional polyorganosiloxane comprises unit formula: (R73SiO1 / 2)q(R72R8SiO1 / 2)r(R72SiO2 / 2)s(SiO4 / 2)t, where R7and R8are as described above, and subscripts q, r, s, and t have average values such that 2 ≥ q ≥ 0, 4 ≥ r ≥ 0, 995 ≥ s ≥ 4, t = 1, (q + r) = 4, and (q + r + s + t) has a value sufficient to impart a viscosity > 170 mPa·s measured by rotational viscometry at 25 °C.

4. The composition of any one of claims 1 to 3, wherein (B) the polyorganohydrogensiloxane comprises unit formula: (R93SiO1 / 2)w(R92HSiO1 / 2)x(R92SiO2 / 2)y(R9HSiO2 / 2)z, wherein each R9is an independently selected monovalent hydrocarbyl group of 1 to 12 carbon atoms; subscripts w, x, y, and z are integers representing average number of units per molecule, and subscripts w, x, y, and z have values such that: w is 0, 1, or 2, x is 0, 1, or 2, a quantity (w + x) has an average value of 2; y ≥ 0, z ≥ 0, a quantity (x + z) ≥ 2, 10,000 ≥ (w + x + y + z) ≥ 2.

5. The composition of any one of claims 1 to 4, wherein (C) (i) the halogenated arylborane Lewis acid comprises tris(pentafluorophenyl)borane.

6. The composition of any one of claims 1 to 5, wherein (C) the catalyst composition further comprises (ii) a Lewis basic amine.

7. The composition of claim 6, wherein (C)(ii) the Lewis basic amine comprises a trialkyl amine, and the trialkyl amine is present in an amount sufficient to provide 1.0 to 1.5 molar equivalents of amine with respect to (i) the halogenated arylborane Lewis acid.

8. The composition of any one of claims 1 to 7, wherein (D) the phenolic antioxidant is selected from the group consisting of 1,3,5-trimethyl-2,4,6-tris(3,5-di-tert-butyl-4- hydroxybenzyl)benzene; 2,5,7,8-tetramethyl-2-(4,8,12-trimethyltridecyl)chroman-6-ol; and a9. The composition of any one of claims 1 to 8, further comprising an additional starting material selected from the group consisting of (D) an antioxidant, (E) a release modifier, (F) an anchorage additive, (G) a solvent, and / or (H) an anti-mist additive, and a combination of two or more thereof.

10. A method for preparing the composition of any one of claims 1 to 9, wherein the method comprises: optionally 1) combining starting materials comprising (A) the aldehyde-functional polyorganosiloxane and (D) the antioxidant, thereby forming a first intermediate mixture; 2) combining (A) the aldehyde-functional polyorganosiloxane or the first intermediate mixture and a starting material comprising (C) the catalyst composition, thereby forming a second intermediate mixture; 3) combining the second intermediate mixture and a starting material comprising (B) the polyorganohydrogensiloxane, thereby forming a reaction mixture.

11. The method of claim 10, further comprising: mixing starting materials comprising (i) the halogenated arylborane Lewis acid, (ii) the Lewis basic amine, and (iii) a solvent before step 1), thereby forming a solution comprising (C) the catalyst composition.

12. The method of claim 10 or claim 11, further comprising: treating (A) the aldehyde- functional organosilicon compound with an adsorbent before step 1).

13. The method of any one of claims 10 to 12, further comprising: adding an additional starting material selected from the group consisting of (D) an antioxidant, (E) a release modifier, (F) an anchorage additive, (G) a solvent, and / or (H) an anti-mist additive, and a combination of two or more thereof.

14. A method for preparing a coated article, wherein the method comprises: I) practicing the method of any one of claims 11 to 13, thereby preparing a curable polyorganosiloxane composition; II) coating the curable polyorganosiloxane composition on a substrate; and III) curing the curable polyorganosiloxane composition to form a cured polyorganosiloxane coating on the substrate, thereby preparing the coated article.

15. The method of claim 14, where the coated article is a release liner.

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