Curable aldehyde – aminosiloxane ester composition and method for its preparation

Abstract

A curable composition includes an aminosiloxane ester copolymer and an aldehyde-functional organosilicon compound. The composition may cure at room temperature without the use of a tin catalyst.

Description

CURABLE ALDEHYDE - AMINOSILOXANE ESTER COMPOSITION AND METHOD FORITS PREPARATIONCROSS REFERENCE TO RELATED APPLICATIONS

[0001] This application claims the benefit of U.S. Provisional Patent Application Serial No. 63 / 564086 filed on 12 March 2024 under 35 U.S.C. §119 (e). U.S. Provisional Patent Application Serial No. 63 / 564086 is hereby incorporated by reference.HELD

[0002] A curable aldehyde-aminosiloxane ester copolymer composition and method for its preparation are provided. More particularly, the composition includes an aldehyde-functional organosilicon compound and an aminosiloxane ester copolymer.INTRODUCTION

[0003] Room temperature vulcanizing (RTV) silicone compositions are useful in a myriad of applications, such as mold making, preparing adhesives, sealants, or elastomers, and forming gaskets (formed in place). RTV silicone compositions are known in the art and can be prepared from one-part compositions, or two-part (base and curing agent) compositions, where the two parts are mixed before use. Typically, RTV silicone compositions contain condensation reaction catalysts, such as dibutyl tin dilaurate, that catalyze condensation reaction cure of the RTV silicone composition. There is an ongoing need in the silicones industry to provide RTV silicone compositions that are free of organotin compounds.

[0004] Catalyst free silicone sealants that cure underwater have been disclosed. Aqueous solutions of glutaraldehyde, glyoxal or formaldehyde react without catalysts with a variety of aminopropyl modified silicone polymers to give silicone elastomers, even underwater. However, these sealants may suffer from the drawbacks of including toxic, volatile aldehydes, which are not compatible with the aminopropyl modified silicone polymers.SUMMARY

[0005] A curable composition comprises: (A) an aminosiloxane ester copolymer, and (B) an aldehyde - functional organosilicon compound. The curable composition may be cured to form a sealant.DETAILED DESCRIPTION

[0006] The composition introduced above comprises a cure package. The cure package comprises, alternatively consists essentially of, alternatively consists of (A) the aminosiloxane ester copolymer and (B) the aldehyde-functional organosilicon compound. Without wishing to be bound by theory, it is thought that composition can cure sufficiently even without the presence of aconventional bis-hydroxyl-terminated polydiorganosiloxane. Furthermore, it is thought that the reaction of the amino moiety from starting material (A) and the aldehyde moiety from starting material (B) will generate water as a side product, which can enhance cure, particularly deep section cure of the composition.(A) Aminosiloxane Ester Copolymer

[0007] Starting material (A) in the composition is an aminosiloxane ester copolymer. The aminosiloxane ester copolymer comprises formula (I):where each R1is an independently selected monovalent hydrocarbon group of 1 to 12 carbon atoms, each REis an independently selected amino-functional group of formula H2N-RA-, each RAis an independently divalent hydrocarbon group of 1 to 12 carbon atoms, each R2is independently selected from the group consisting of hydrogen and methyl, each RDis an independently selected divalent hydrocarbon group of 2 to 20 carbon atoms, each subscript a independently has a value such that 0 < a < 150; and subscript has a value such that 1 < b < 100.

[0008] Suitable monovalent hydrocarbon groups for R1include alkyl, alkenyl, aryl, and combinations thereof (e.g., aralkyl and aralkenyl). For example, suitable alkyl groups include methyl, ethyl, propyl (including iso-propyl and n-propyl), butyl (including iso-butyl, n-butyl, secbutyl, and tert-butyl), pentyl (including linear pentyl and / or cyclopentyl) and branched alkyl groups with 5 carbon atoms, hexyl (including linear hexyl and / or cyclohexyl) and branched alkyl groups with 6 carbon atoms), octyl (including linear octyl and / or cyclooctyl), branched alkyl groups with 8 carbon atoms), decyl (including linear decyl and / or cyclodecyl) and branched alkyl groups with 10 carbon atoms, and dodecyl (including linear dodecyl and / or cyclododecyl) and branched alkyl groups with 12 carbon atoms. Alternatively, the alkyl group for R1may be selected from the group consisting of methyl and ethyl. Alternatively, each R1may be methyl. Suitable alkenyl groups for R1include vinyl, allyl and hexenyl; alternatively vinyl or allyl; and alternatively vinyl. Suitable aryl groups for R1may include cyclopentadienyl, phenyl, naphthyl, and anthracenyl. Alternatively, the aryl group for R1may be phenyl. Aralkyl groups such as benzyl, tolyl, xylyl, 1 -phenylethyl, and 2-phenylethyl, and aralkenyl groups such as styryl, may also be used for R1. Alternatively, each R1may be selected from the group consisting of methyl and phenyl. Alternatively, each R1may be methyl.

[0009] Each REis an independently selected amino-functional group of formula H2N-RA-, where RAis a divalent hydrocarbon group. Alternatively, each REmay be hydroxyl. Each RAis an independently selected divalent hydrocarbon group of 1 to 12 carbon atoms, alternatively 2 to 12 carbon atoms, alternatively 2 to 5 carbon atoms, and alternatively 2 to 3 carbon atoms. The divalent hydrocarbon groups for RAmay be linear, branched, or cyclic, or combinations thereof. Suitable divalent hydrocarbon groups for RAinclude alkylene groups, arylene groups, and combinations thereof (e.g., dialkylarylene groups). The alkylene group is exemplified by groups of empirical formula -C2H4-, -C3H6-, and -C4H8-, e.g., ethylene, propylene, and butylene. The arylene group for RAmay be arylene group such as phenylene. Alternatively, RAmay be a dialkylarylene group such as:independently 1 to 6, alternatively 1 to 2. Alternatively, each RAmay be an alkylene group such as ethylene, propylene, or butylene; alternatively ethylene.

[0010] Each R2is independently selected from the group consisting of hydrogen and methyl. Alternatively, each R2may be hydrogen.

[0011] Each RDis an independently selected divalent hydrocarbon group of 2 to 20 carbon atoms, alternatively 2 to 12 carbon atoms, alternatively 3 to 12 carbon atoms, alternatively 4 to 12 carbon atoms, and alternatively 4 to 10 carbon atoms. The divalent hydrocarbon groups for RDmay be linear, branched, cyclic, or combinations thereof. Suitable divalent hydrocarbon groups for RDinclude alkylene groups, arylene groups, and combinations thereof. Alternatively, each RDmay be an alkylene group such as propylene, butylene, hexylene, octy lene, decylene, or dodecylene; alternatively each RDmay be butylene, hexylene, or decylene. Alternatively, RDmay be a branched alkylene group. The arylene group for RDmay be arylene group such as phenylene. Alternatively, RDmay be a dialkylarylene group as described above for RA.

[0012] Subscript a has a value such that 0 < a < 150. Alternatively, subscript a may have a value of at least 2, alternatively at least 14, alternatively at least 16, alternatively at least 30; while at the same time, subscript a may have a value up to 86, alternatively up to 84, alternatively up to 44. Alternatively, subscript a may have a value of 2 to 145, alternatively 14 to 86, alternatively 16 to 84, alternatively 30 to 84, alternatively 16 to 44, alternatively 42 to 86, and alternatively 44 to 84.

[0013] Subscript b has a value such that 1 < b < 100. Alternatively, subscript b may have a value of at least 2, alternatively at least 3, alternatively at least 4, and alternatively at least 5; while at the same time, subscript b may have a value up to 100, alternatively up to 50, alternatively up to 25, alternatively up to 20, alternatively up to 10, and alternatively up to 5. Alternatively, subscript b may have a value of 2 to 20, alternatively 2 to 10, and alternatively 2 to 5.

[0014] The copolymer described above may have a number average molecular weight (Mn) of > 1 ,000 g / mole to 250,000 g / mole measured by GPC. GPC can be used to measure the number averaged molecular weight (Mn) and weighted average molecular weight (Mw) of the copolymers. Measurements were conducted using the system described in the table below. The samples were prepared at 10 mg / mL concentration in 20 mL scintillation vials and capped with acetic anhydride. The samples were shaken using a wrist shaker for 2 hours prior to being filtered through 0.45 pm PTFE syringe filters into 2 mL GC vials. The samples were placed on the autosampler and data collection started. Data collection occurred over 30 minutes and the data were processed and analyzed against polystyrene standards ranging from 580 to 2,750,000 Daltons.Alternatively, the copolymer may have a Mn of 4,000 g / mole to 250,000 g / mole, alternatively 4,000 g / mole to 100,000 g / mole, measured by GPC.

[0015] Alternatively, the copolymer described above may have a weight average molecular weight (Mw) of 2,000 g / mol to 400,000 g / mol. Alternatively, Mw may be 10,000 g / mol to 390,000 g / mol; alternatively 12,000 g / mol to 200,000 g / mol; alternatively 15,000 g / mol to 185,000 g / mol; alternatively 19,000 g / mol to 175,000 g / mol; alternatively 20,000 g / mol to 100,000 g / mol; alternatively 21,000 g / mol to 80,000 g / mol; alternatively 22,000 g / mol to 75,000 g / mol; alternatively 25,000 g / mol to 65,000 g / mol; alternatively 30,000 g / mol to 60,000 g / mol; alternatively 35,000 g / mol to 55,000 g / mol; and alternatively 40,000 g / mol to 50,000 g / mol.

[0016] Aminosiloxane ester copolymers may be prepared as described in PCT Patent Publication WO2023 / 278918 to Rekken et al. corresponding to US Patent Application Serial No. 18 / 552681, which is hereby incorporated by reference for describing aminosiloxane ester copolymers andmethods for their preparation.(B ) Aldehyde-Functional Organosilicon Compound

[0017] Starting material (B) in the composition is an aldehyde-functional organosilicon compound. The aldehyde-functional organosilicon compound has, per molecule, at least one aldehyde-functional group covalently bonded to silicon. Alternatively, the aldehyde-functional organosilicon compound may have, per molecule, more than one aldehyde-functional group covalently bonded to silicon, alternatively at least two aldehyde-functional groups per molecule, and alternatively at least aldehyde-functional groups per molecule. The aldehyde- functional group covalently bonded to silicon may have formula:divalent hydrocarbon group free of aliphatic unsaturation that has 2 to 8 carbon atoms. G may be linear or branched. Examples of divalent hydrocarbyl groups for G include alkane-diyl groups of empirical formula -CrH2r-, where subscript r 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-diyl,Alternatively, each G may be an alkane-diyl group of 2 to 6 carbon atoms; alternatively of 2, 3, or 6 carbon atoms. The aldehyde-functional organosilicon compound may be one aldehyde-functional organosilicon compound. Alternatively, two or more aldehyde-functional organosilicon compounds that differ from one another may be used in the process described herein. For example, the aldehyde-functional organosilicon compound may comprise one or both of an aldehyde-functional silane and an aldehyde-functional polyorganosiloxane.

[0018] The aldehyde-functional organosilicon compound may comprise an aldehyde-functional silane of formula (Bl): RAldxSiR4(4-X), where each RAldis an independently selected group of the formuladescribed above; and each R4is independently selected from the group consisting of an alkyl group of 1 to 18 carbon atoms, an aryl group of 6 to 18 carbon atoms, an acyloxy group of 2 to 18 carbon atoms, and a hydrocarbonoxy-functional group of 1 to 18 carbon atoms; and subscript x is 1 to 4. Alternatively, subscript x may be 1 or 2, alternatively 2, andalternatively 1. Alternatively, each R4may be independently selected from the group consisting of an alkyl group of 1 to 18 carbon atoms, an aryl group of 6 to 18 carbon atoms, and an alkoxyfunctional group of 1 to 18 carbon atoms. Alternatively, in formula (Bl) each R4may be an alkoxyfunctional group of 1 to 18 carbon atoms or an acyloxy group of 2 to 18 carbon atoms; alternatively, methoxy, ethoxy, or acetoxy. Alternatively, in formula (Bl), when subscript x = 1, at least one instance of R4may be a hydrocarbonoxy group or an acyloxy group, alternatively at least two instances of R4.

[0019] Suitable aldehyde- functional silanes are exemplified by aldehyde-functional trialkoxysilanes such as (butyl-aldehyde)trimethoxysilane, (propyl-aldehyde)-trimethoxysilane, (propyl-aldehyde)-triethoxysilane, (propyl-aldehyde)-triisopropoxysilane, and (propyl-aldehyde)- tns(methoxy ethoxy )silane; aldehyde- functional dialkoxysilanes such as (propyl-aldehyde)- phenyldiethoxysilane, (propyl-aldehyde)-methyldimethoxysilane, and (propyl-aldehyde)- methyldiethoxysilane; aldehyde-functional monoalkoxysilanes such as tri(propyl- aldehyde) - methoxysilane; aldehyde-functional triacyloxysilanes such as (propyl-aldehyde)-triacetoxysilane, and aldehyde-functional diacyloxysilanes such as (propyl-aldehyde)-methyldiacetoxysilane.

[0020] Alternatively, the aldehyde-functional organosilicon compound may comprise (B2) an aldehyde-functional polyorganosiloxane. Said aldehyde-functional polyorganosiloxane may be cyclic, linear, branched, resinous, or a combination of two or more thereof. Said aldehyde- functional polyorganosiloxane may have at least 1, alternatively at least 2, and alternatively at least 3 aldehyde groups per molecule. Said aldehyde-functional polyorganosiloxane may comprise unit formula (B2-1): (R43SiOi / 2)a(R42RAldSiOi / 2)b(R42SiO2 / 2)c(R4RAldSiO2 / 2)d(R4SiO3 / 2)e(RAldSiO3 / 2)f(SiO4 / 2)g(ZOi / 2)h; where each RAldis an independently selected aldehyde group of the formuladescribed above, and R4, Z, and subscripts a, b, c, d, e, f, g, and h are as described above.Alternatively, each R4may be independently selected from the group consisting of an alkyl group of 1 to 18 carbon atoms, an aryl group of 6 to 18 carbon atoms, and a hydrocarbonoxy group of 1 to 18 carbon atoms. Alternatively, in formula (B2-1) each R4may 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 Z is independently selected from the group consisting of a hydrogen atom and R5, where each R5is independently selected from the group consisting of alkyl groups of 1 to 18 carbon atoms and aryl groups of 6 to 18 carbon atoms. Subscripts a, b, c, d, e, f, and g represent average numbers, per molecule, of each unit in the unit formula. Subscripts a, b, c, d, e, f, and g and havevalues such that subscript a > 0, subscript b > 0, subscript c > 0, subscript d > 0, subscript e > 0, subscript f > 0, subscript g > 0; and subscript h has a value such that 0 < h / (e + f + g) < 1.5, 10,000 > (a + b + c + d + e + f + g) > 2, and a quantity (b + d + f) > 1. At the same time, the quantity (a + b + c + d + e + f + g) may be < 10,000. Alternatively, in the unit formula (B2-1) for the aldehyde- functional polyorganosiloxane, each R4may be independently selected from the group consisting of an alkyl group of 1 to 18 carbon atoms, an aryl group of 6 to 18 carbon atoms, and a hydrocarbonoxy-functional group of 1 to 18 carbon atoms. Alternatively, each R4may be independently selected from the group consisting of an alkyl group of 1 to 18 carbon atoms, an aryl group of 6 to 18 carbon atoms, and an alkoxy-functional group of 1 to 18 carbon atoms. Alternatively, each R4may 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 Z may be hydrogen or an alkyl group of 1 to 6 carbon atoms. Alternatively, each Z may be hydrogen.

[0021] Alternatively, (B2) the aldehyde-functional polyorganosiloxane may comprise (B2-2) a linear polydiorganosiloxane having, per molecule, at least one aldehyde-functional group; alternatively at least two aldehyde-functional groups (e.g., when in the formula (B2- 1) for the aldehyde-functional polyorganosiloxane above, subscripts e = f = g = 0). For example, said polydiorganosiloxane may comprise unit formula (B2-3): (R43SiOi / 2)a(RAldR42SiOi / 2)b(R42SiO2 / 2)c(RAldR4SiO2 / 2)d, where RAldand R4are as described above, subscript a is 0, 1, or 2; subscript b is 0, 1, or 2, subscript c > 0, subscript d > 0, with the provisos that a quantity (b + d) > 1, a quantity (a + b) = 2, and a quantity (a + b + c + d) > 2. Alternatively, in the unit formula (B2-3) for the linear aldehyde-functional polyorganosiloxane, above, the quantity (a + b + c + d) 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. Alternatively, subscript c > 0, subscript d > 0, with the provisos that a quantity (b + d) > 1, and a quantity 1 < (c + d) < 180. Alternatively, in the unit formula for the linear aldehyde- functional polyorganosiloxane, each R4may be independently selected from the group consisting of alkyl and aryl; alternatively methyl and phenyl. Alternatively, each R4in said formula may be an alkyd group; alternatively each R4may be methyl.

[0022] Starting material (B2) may comprise an aldehyde-functional polydiorganosiloxane such as i) bis-dimethyl(propyl-aldehyde)siloxy-terminated polydimethylsiloxane, ii) bis-dimethyl(propyl- aldehyde)siloxy-terminated poly(dimethylsiloxane / methyl(propyl-aldehyde)siloxane), iii) bis- dimethyl(propyl-aldehyde)siloxy-terminated polymethyl(propyl-aldehyde)siloxane, iv) bis-trimethylsiloxy-terminated poly(dimethylsiloxane / methyl(propyl-aldehyde)siloxane), v) bis- trimethylsiloxy-terminated polymethyl(propyl-aldehyde)siloxane, vi) bis-dimethyl(propyl- aldehyde)siloxy-terminated poly(dimethylsiloxane / methylphenylsiloxane / methyl(propyl- aldehyde)siloxane), vii) bis-dimethyl(propyl-aldehyde)siloxy-terminated poly(dimethylsiloxane / methylphenylsiloxane), viii) bis-dimethyl(propyl-aldehyde)siloxy- terminated poly(dimethylsiloxane / diphenylsiloxane), ix) bis-phenyl, methyl, (propyl- aldehyde) - siloxy-terminated polydimethylsiloxane, x) bis-dimethyl(heptyl-aldehyde)siloxy-terminated polydimethylsiloxane, xi) bis-dimethyl(heptyl-aldehyde)siloxy-terminated poly(dimethylsiloxane / methyl(heptyl-aldehyde)siloxane), xii) bis-dimethyl(heptyl-aldehyde)siloxy- terminated polymethyl(heptyl-aldehyde)siloxane, xiii) bis-trimethylsiloxy-terminated poly(dimethylsiloxane / methyl(heptyl-aldehyde)siloxane), xiv) bis-trimethylsiloxy-terminated polymethyl(heptyl-aldehyde)siloxane, xv) bis -dimethyl(heptyl- aldehyde) -siloxy terminated poly(dimethylsiloxane / methylphenylsiloxane / methyl(heptyl-aldehyde)siloxane), xvi) bis- dimethyl(propyl-aldehyde)siloxy-terminated poly(dimethylsiloxane / methyl(heptyl- aldehyde)siloxane), xvii) bis-dimethyl(heptyl-aldehyde)-siloxy-terminated poly(dimethylsiloxane / methylphenylsiloxane), xviii) dimethyl(heptyl-aldehyde)-siloxy-terminated poly(dimethylsiloxane / diphenylsiloxane), and xix) a combination of two or more of i) to xviii).

[0023] Alternatively, (B2) the aldehyde-functional polyorganosiloxane may be oligomeric, e.g. , when in unit formula (B2-1) above the quantity (a + b + c + d -l- e -l- f -l- g) < 50, alternatively < 40, alternatively < 30, alternatively < 25, alternatively < 20, alternatively < 10, alternatively < 5, alternatively < 4, alternatively < 3. Examples of linear aldehyde-functional polyorganosiloxaneoligomers may have formula: , where R4is as described above, each R3is independently selected from the group consisting of R4and RAld, with the proviso that at least one R3, per molecule, is RAld, and subscript z is 0 to 48. Examples of linear aldehyde- functional polyorganosiloxane oligomers include l,3-di(propyl-aldehyde)-l, 1,3,3- tetramethyldisiloxane; l,l,l,3,3-pentamethyl-3-(propyl-aldehyde)-disiloxane; and 1,1, 1,3, 5, 5, 5- heptamethyl-3-(propyl-aldehyde)-trisiloxane.

[0024] Suitable aldehyde-functional organosilicon compounds are known in the art and may be prepared by known methods, such as those described in US Patent 4424392 to Petty; 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 0 392 948 Alto Frances, US Patent Application Publication 20230242711 to Fisk et al., and PCT Patent Application Publications W02006027074 to Kiihnle et al., W02023200934 to Tulchinsky et al., and WO2023091868 to Han et al. PCT Publications W02023200934 and WO2023091868 and US Patent Application Publication 20230242711 are hereby incorporated by reference.

[0025] The amounts of (A) the aminosiloxane ester copolymer and (B) the aldehyde-functional organosilicon compound used in the composition depend on various factors including the type and amount of any additional starting materials (described below) that may be added to the composition and the desired properties and end use of the cured product of the composition. However, the amounts of (A) the aminosiloxane ester copolymer and (B) the aldehyde-functional organosilicon compound may be sufficient to provide a molar ratio of reactive amine moieties from starting material (A) to aldehyde moieties of starting material (B) (NH / CHO ratio) of at least 0.25 / 1, alternatively at least 0.4 / 1, alternatively at least 0.48 / 1, alternatively > 1 / 1, alternatively at least 1.02 / 1, alternatively at least 1.1 / 1, alternatively at least 1.2 / 1, alternatively at least 1.3 / 1, alternatively at least 1.4 / 1, alternatively at least 1.5 / 1, alternatively at least 1.6 / 1, alternatively at least 1.7 / 1, alternatively at least 1.8 / 1, alternatively at least 1.9 / 1, and alternatively at least 2 / 1; while at the same time, the NH / CHO ratio may be < 4.22 / 1, alternatively up to 4 / 1, alternatively up to 3 / 1, alternatively up to 2.9 / 1, alternatively up to 2.8 / 1, alternatively up to 2.7 / 1, alternatively up to 3.5 / 1, alternatively up to 3.4 / 1, alternatively up to 3.3 / 1, alternatively up to 3.2 / 1, alternatively up to 3.1 / 1, alternatively up to 3 / 1, alternatively up to 29 / 1, alternatively up to 2.8 / 1, alternatively up to 2.7 / 1, alternatively up to 2.6 / 1, alternatively up to 2.5 / 1, alternatively up to 2.4 / 1, alternatively up to 2.3 / 1, alternatively up to 2.2 / 1, alternatively up to 2.1 / 1, and alternatively up to 2 / 1. The inventors surprisingly found that if NH / CHO ratio is too high (e.g., > 18 / 1, too much excess amine), or if the NH / CHO ratio is too low (e.g., < 0.25 / 1, too much excess aldehyde) the composition may fail to cure even after 4 days at room temperature. Alternatively, the NH / CHO ratio may be 0.25 / 1 to < 4.22 / 1, alternatively 0.4 / 1 to < 4.22 / 1, alternatively 0.4 / 1 to 4 / 1, alternatively > 1 / 1 to < 4.22 / 1, alternatively 1.02 / 1 to 2.57 / 1, alternatively 1.4 / 1 to 2.6 / 1, alternatively 01.4 / 1 to 2.3 / 1, alternatively 1.8 / 1 to 2.3 / 1 and alternatively 1.02 / 1 to 2.57 / 1.Optional Additional Starting Materials

[0026] The composition described herein may optionally further comprise an additional starting material selected from the group consisting of (C) a crosslinker; (D) a drying agent; (E) an extender, a plasticizer, or a combination thereof; (F) a filler; (G) a filler treating agent; (H) a biocide; (J) a flame retardant; (K) a surface modifier (e.g., adhesion promoter or release additive); (L) a chain lengthened (M) an endblocker; (N) a nonreactive binder; (O) an anti-aging additive (e.g., antioxidant); (P) a water release agent; (Q) a colorant (e.g., inorganic pigment or organic dye); (R) arheological additive; (S) a vehicle (such as a solvent and / or a diluent); (T) a tackifying agent; (U) a corrosion inhibitor; (V) an encapsulating agent; (W) a catalyst; and a combination of two or more thereof. Exemplary additional starting materials are disclosed, for example, in US Patent 9328205 to Brandstadt et al.(C) Crosslinker

[0027] Starting material (C) is a crosslinker that may be added to the composition, for example, when to increase crosslink density of the reaction product prepared by curing the composition. Generally, starting material (C) is selected with functionality that can vary depending on the degree of crosslinking, modulus, or other properties desired in the reaction product of the composition. Generally, the selection of (C) the crosslinker is made such that the composition remains sufficiently reactive to be useful during storage for several months in a moisture impermeable package. Generally, (C) the crosslinker is selected such that the hydrolyzable substituents on starting material (C) are reactive with the substituents on starting materials (A), (B), or a reaction product thereof. For example, when (B) is an aldehyde-functional alkoxysilane, then (C) the crosslinker may include a hydrolyzable substituent reactive with alkoxy groups, such as an alkoxy group. The exact amount of (C) the crosslinker can vary depending on factors including the type of (A) aminosiloxane ester copolymer and (B) aldehyde-functional organosilicon compound selected and the desired crosslink density of the reaction product. However, the amount of crosslinker may range from 0.5 to 100 parts based on 100 parts by weight of starting materials (A) and (B).

[0028] Starting material (C) may comprise an alkoxysilane exemplified by a dialkoxysilane, such as a dialkyldialkoxysilane; a tnalkoxysilane, such as an alkyltrialkoxysilane; a tetraalkoxysilane; or partial or full hydrolysis products thereof, or another combination thereof. Examples of suitable trialkoxysilanes include methyltrimethoxysilane, methyltriethoxysilane, ethyltrimethoxysilane, ethyltriethoxysilane, isobutyltrimethoxysilane, isobutyltriethoxysilane, and a combination thereof, and alternatively methyltrimethoxysilane. Examples of suitable tetraalkoxysilanes include tetraethoxysilane. The amount of the alkoxysilane that is used in the curable silicone composition may range from 0.5 to 15, parts by weight per 100 parts by weight of starting material (B).(D) Drying agent

[0029] Starting material (D) is a drying agent that may optionally be added from the composition. The drying agent binds water from various sources. For example, the drying agent may bind byproducts of the reaction between the amino-functional groups from starting material (A) and the aldehyde functional groups from starting material (B), where such by-products include water.

[0030] Examples of suitable adsorbents for starting material (D) may be inorganic particulates. The adsorbent may have a particle size of 10 micrometers or less, alternatively 5 micrometers orless. The adsorbent may have average pore size sufficient to adsorb water and alcohols, for example 10 A (Angstroms) or less, alternatively 5 A or less, and alternatively 3 A or less. Examples of adsorbents include zeolites such as chabasite, mordenite, and analcite; molecular sieves such as alkali metal alumino silicates, silica gel, silica-magnesia gel, activated carbon, activated alumina, calcium oxide, and combinations thereof.

[0031] Examples of commercially available drying agents include dry molecular sieves, such as 3 A (Angstrom) molecular sieves, which are commercially available from Grace Davidson under the trademark SYLOSIV™ and from Zeochem of Louisville, Kentucky, U.S.A, under the trade name PURMOL, and 4 A molecular sieves such as Doucil zeolite 4A available from Ineos Silicas of Warrington, England. Other useful molecular sieves include MOLSIV ADSORBENT TYPE 13X, 3 A, 4A, and 5A, all of which are commercially available from UOP of Illinois, U.S.A.; SILIPORITE NK 30AP and 65xP from Atofina of Philadelphia, Pennsylvania, U.S.A.; and molecular sieves available from W.R. Grace of Maryland, U.S.A.

[0032] Alternatively, the drying agent may bind the water by chemical means. An amount of a silane crosslinker added to the composition (in addition to starting material (C)) may function as a chemical drying agent. Without wishing to be bound by theory, it is thought that the chemical drying agent may be added to a one part composition, or to one or more parts of a multiple part composition, to keep the composition free from atmospheric moisture after the parts of the composition are mixed together. For example, alkoxysilanes suitable as drying agents include alkyltrialkoxysilanes such as methyltrimethoxysilane, methyltriethoxysilane, and a combination thereof; alkenyltrialkoxysilanes such as vinyltrimethoxysilane, vinyltriethoxy silane, and a combination thereof; cyanoalkyltrialkoxysilanes such as cyanoethyltrimethoxysilane, cyanoethyltriethoxysilane, and a combination thereof. The amount of starting material (D) depends on the specific drying agent selected. However, when (D) is a chemical drying agent, the amount may range from 0 parts to 5 parts, alternatively 0.1 parts to 0.5 parts, per 100 parts by weight of the composition.(E) Extender

[0033] Starting material (E) is an extender and / or a plasticizer. An extender comprising a nonfunctional polyorganosiloxane may be used in the composition. Non- functional polyorganosiloxanes are known in the art and are commercially available. Suitable non- functional polyorganosiloxanes are exemplified by, but not limited to, polydimethylsiloxanes. Such polydimethylsiloxanes include DOW SILICONES™ 200 Fluids, which are commercially available from Dow Silicones Corporation of Midland, Michigan, U.S.A, and may have viscosity ranging from 50 cSt to 100,000 cSt, alternatively 50 cSt to 50,000 cSt, alternatively 100 cSt to 50,000 cSt,and alternatively 12,500 to 60,000 cSt.

[0034] An organic plasticizer may be used in addition to, or instead of, the non-functional polyorganosiloxane extender described above. Organic plasticizers are known in the art and are commercially available. The organic plasticizer may comprise a phthalate, a carboxylate, a carboxylic acid ester, an adipate or a combination thereof. Alternatively, a polymer plasticizer can be used. Examples of the polymer plasticizer include alkenyl polymers obtained by polymerizing vinyl or allyl monomers by means of various methods; polyalky lene glycol esters such as diethylene glycol dibenzoate, diethylene glycol dibenzoate and pentaerythritol ester; polyester plasticizers obtained from dibasic acids such as sebacic acid, adipic acid, azelaic acid and phthalic acid and dihydric alcohols such as ethylene glycol, diethylene glycol, triethylene glycol, propylene glycol and dipropylene glycol; poly ethers including polyether polyols each having a molecular weight of not less than 500 such as polyethylene glycol, polypropylene glycol and polytetramethylene glycol, polystyrenes such as polystyrene and poly-alpha-methylstyrene; and polybutadiene, polybutene, polyisobutylene, butadiene acrylonitrile, and polychloroprene.

[0035] When the organic plasticizer is present, the amount of the organic plasticizer may range from 5 to 150 parts by weight based on the combined weights of all starting materials in the composition. The exact amount of starting material (E) used in the composition can depend on various factors including the desired end use of the composition and the cured product thereof. However, the amount of starting material (E) may range from 0.1 % to 10 % based on the combined weights of all starting materials in the composition.(F) Filler

[0036] Starting material (F) is a filler. The filler may comprise a reinforcing filler, an extending filler, a conductive filler, or a combination thereof. For example, the composition may optionally further comprise starting material (fl), a reinforcing filler, which when present may be added in an amount ranging from 0.1 % to 95 %, alternatively 1 % to 60 %, based on the weight of the composition. The exact amount of starting material (fl) depends on various factors including the form of the reaction product of the composition and whether any other fillers are added. Examples of suitable reinforcing fillers include reinforcing silica fillers such as fume silica, silica aerogel, silica xerogel, and precipitated silica. Fumed silicas are known in the art and commercially available; e.g., fumed silica sold under the name CAB-O-SIL by Cabot Corporation of Massachusetts, U.S.A.

[0037] The composition may optionally further comprise starting material (f2) an extending filler in an amount ranging from 0.1 % to 95 %, alternatively 1 % to 60 %, and alternatively 1 % to 20 %, based on the weight of the composition. Examples of extending fillers include crushed quartz,aluminum oxide, magnesium oxide, calcium carbonate such as ground or precipitated calcium carbonate, zinc oxide, talc, diatomaceous earth, iron oxide, clays, mica, chalk, titanium dioxide, zirconia, sand, carbon black, graphite, hollow or plain glass beads, hollow plastics or a combination thereof. Extending fillers are known in the art and commercially available; such as a ground silica sold under the name MIN-U-SIL by U.S. Silica of Berkeley Springs, WV. Suitable precipitated calcium carbonates included Winnofil™ SPM from Solvay and U1 trapflex™ and Ultrapflex™ 100 from SMI.

[0038] The composition may optionally further comprise starting material (f3) a conductive filler. Conductive fillers may be thermally conductive, electrically conductive, or both. Conductive fillers are known in the art and are exemplified by metal particulates, metals coated on nonconductive substrates; metal oxides, meltable fillers (e.g., solder), aluminum nitride, aluminum trihydrate, barium titanate, boron nitride, carbon fibers, diamond, graphite, magnesium hydroxide, onyx, silicon carbide, tungsten carbide, and a combination thereof.

[0039] Alternatively, other fillers may be added to the composition, the type and amount depending on factors including the end use of the cured product of the composition. Examples of such other fillers include fibrous fillers such as glass fibers, carbon fibers and organic fibers, magnetic particles such as ferrite; and dielectric particles such as fused glass microspheres, titania, and calcium carbonate.(G) Treating Agent

[0040] The composition may optionally further comprise starting material (G) a treating agent. The amount of (G) the treating agent can vary depending on factors such as the type of treating agent selected and the type and amount of particulates to be treated, and whether the particulates are treated before being added to the composition, or whether the particulates are treated in situ.However, starting material (G) may be used in an amount ranging from 0.01 % to 20 %, alternatively 0.1 % to 15 %, and alternatively 0.5 % to 5 %, based on the weight of the composition. Particulates, such as the filler, the physical drying agent, certain flame retardants, certain pigments, and / or certain water release agents, when present, may optionally be surface treated with starting material (G). Particulates may be treated with starting material (G) before being added to the composition, or in situ. Starting material (G) may comprise an alkoxysilane, an alkoxy-functional oligosiloxane, a cyclic polyorganosiloxane, a hydroxyl-functional oligosiloxane such as a dimethyl siloxane or methyl phenyl siloxane, or a fatty acid.(H) Biocide

[0041] Starting material (H) is a biocide. The amount of starting material (H) can vary depending on factors including the type of biocide selected and the benefit desired. However, the amount ofstarting material (H) may range from greater than 0 % to 5 % based on the weight of all starting materials in the composition. Starting material (H) is exemplified by (hl) a fungicide, (h2) an herbicide, (h3) a pesticide, (h4) an antimicrobial, or a combination thereof.(J) Flame Retardant

[0042] Starting material (J) is a flame retardant. Suitable flame retardants may include, for example, carbon black, hydrated aluminum hydroxide, and silicates such as wollastonite, platinum and platinum compounds. Alternatively, the flame retardant may be a halogen based flameretardant, a phosphorus based flame-retardant, or a tetraalkyl lead compound. The amount of flame retardant can vary depending on factors such as the flame retardant selected and whether solvent is present. However, the amount of flame retardant in the composition may range from greater than 0 % to 10 % based on the combined weight of all starting materials in the composition.(K) Surface Modifier

[0043] Starting material (K) is a surface modifier. Suitable surface modifiers are exemplified by (kl) an adhesion promoter or (k2) a release agent. Suitable adhesion promoters for starting material (kl) may comprise a transition metal chelate, a hydrocarbonoxy silane such as an alkoxysilane, a combination of an alkoxysilane and a hydroxy-functional polyorganosiloxane, or a combination thereof. Adhesion promoters are known in the art and may comprise silanes having the formula R24tR25sSi(OR26)4-(t +s) where each R24is independently a monovalent organic group having at least 3 carbon atoms; R25contains at least one SiC bonded substituent having an adhesion-promoting group, such as amino, epoxy, mercapto or acry late groups; subscript t has a value ranging from 0 to 2; subscript s is either 1 or 2; and the sum of (t + s) is not greater than 3. Each R26is independently a saturated hydrocarbon group. Saturated hydrocarbon groups for R26may be, for example, an alkyl group of 1 to 4 carbon atoms, alternatively 1 to 2 carbon atoms. R26is exemplified by methyl, ethyl, propyl, and butyl. Alternatively, the adhesion promoter may comprise a partial condensate of the above silane. Alternatively, the adhesion promoter may comprise a combination of an alkoxysilane and a hydroxy-functional polyorganosiloxane.

[0044] Alternatively, the adhesion promoter may comprise an unsaturated or epoxy-functional compound. The adhesion promoter may comprise an unsaturated or epoxy-functional alkoxysilane. Examples of suitable epoxy-functional alkoxysilanes include 3-glycidoxypropyltrimethoxysilane, 3- glycidoxypropyltriethoxysilane, (epoxycyclohexyl)ethyldimethoxysilane, (epoxycyclohexyl)ethyldiethoxysilane and combinations thereof. Examples of suitable unsaturated alkoxysilanes include vinyltrimethoxysilane, allyltrimethoxysilane, allyltriethoxysilane, hexenyltrimethoxysilane, undecylenyltrimethoxysilane, 3-methacryloyloxypropyl trimethoxysilane, 3-methacryloyloxypropyl triethoxysilane, 3 -acryloyloxypropyl trimethoxysilane, 3-acryloyloxypropyl triethoxysilane, and combinations thereof.

[0045] Alternatively, the adhesion promoter may comprise an epoxy-functional siloxane such as a reaction product of a hydroxy-terminated polyorganosiloxane with an epoxy-functional alkoxysilane, as described above, or a physical blend of the hydroxy-terminated polyorganosiloxane with the epoxy-functional alkoxysilane. The adhesion promoter may comprise a combination of an epoxy-functional alkoxysilane and an epoxy-functional siloxane. For example, the adhesion promoter is exemplified by a mixture of 3-glycidoxypropyltrimethoxysilane and a reaction product of hydroxy-terminated methylvinylsiloxane with 3-glycidoxypropyltrimethoxysilane, or a mixture of 3-glycidoxypropyltrimethoxysilane and a hydroxy-terminated methylvinylsiloxane, or a mixture of 3-glycidoxypropyltrimethoxysilane and a hydroxy-terminated methylvinyl / dimethylsiloxane copolymer. Alternatively, the adhesion promoter may comprise a transition metal chelate. Suitable transition metal chelates include titanates, zirconates such as zirconium acetylacetonate, aluminum chelates such as aluminum acetylacetonate, and combinations thereof.

[0046] Starting material (k2) is a release agent. Suitable release agents are exemplified by fluorinated compounds, such as fluoro-functional silicones, or fluoro-functional organic compounds. Alternatively, the surface modifier for starting material (K) may be used to change the appearance of the surface of a reaction product of the composition. For example, surface modifier may be used to increase gloss of the surface of a reaction product of the composition. Such a surface modifier may comprise a polydiorganosiloxane with alkyl and aryl groups. For example, DOWSIL™ 550 Fluid is a trimethylsiloxy-terminated poly(dimethyl / methylphenyl)siloxane with a viscosity of 125 cSt that is commercially available from Dow Silicones Corporation.

[0047] The exact amount of starting material (K) depends on various factors including the type of surface modifier selected as starting material (K) and the end use of the composition and its reaction product. However, starting material (K), when present, may be added to the composition in an amount ranging from 0.01 to 50 weight parts based on the weight of the composition, alternatively 0.01 to 10 weight parts, and alternatively 0.01 to 5 weight parts.(L) Chain Lengthener / Co-crosslinker

[0048] Chain lengtheners may include difunctional silanes and difunctional siloxanes, which extend the length of polyorganosiloxane chains before crosslinking occurs. Chain lengtheners may be used to reduce the modulus of elongation of the cured product. Chain lengtheners and crosslinkers compete in their reactions with the reactive moieties of starting materials (A) and (B). To achieve noticeable chain extension, the difunctional silane has substantially higher reactivity than the trifunctional crosslinker with which it is used. Suitable chain lengtheners include diamines, such as alkyl, aryl diamines; diamidosilanes such as dialkyldiacetamidosilanes oralkenylalkyldiacetamidosilanes, particularly methylvinyldi(N-methylacetamido)silane, or dimethyldi(N-methylacetamido)silane, diacetoxysilanes such as dialkyldiacetoxysilanes or alkylalkenyldiacetoxysilanes, diaminosilanes such as dialkyldiaminosilanes or alkylalkenyldiaminosilanes, dialkoxy silanes such as dimethyldimethoxy silane, dimethyldiethoxysilane and a-aminoalkyldialkoxyalkylsilanes, polydialkylsiloxanes having a degree of polymerization of from 2 to 25 and having an average per molecule of at least two hydrolyzable groups, such as acetamido or acetoxy or amino or alkoxy or amido or ketoximo substituents, and diketoximinosilanes such as dialkylkdiketoximinosilanes and alkylalkenyldiketoximinosilanes.

[0049] Alternatively, the chain lengthener may be a bis -hydroxyl terminated polydiorganosiloxane. The bis-hydroxyl terminated polydiorganosiloxane may comprise formula:each R7is an independently selected monovalent hydrocarbyl group, as described and exemplified above for R5. Alternatively, each R7may be an alkyl group, alternatively methyl. Subscript z > 1, and subscript z has a value sufficient to give the bis-hydroxyl polydiorganosiloxane a viscosity of 250 mPa s to 1,000 mPa s at 25 °C measured by a Modular Compact Rheometer (MCR) 302 from Anton Paar GmbH of Graz, Austria using the most suitable settings and plates for the viscosity concerned, for example using a 25mm diameter rotational plate with a gap of 0.3 mm at a shear rate of ls-1. The -hydroxyl terminated polydiorganosiloxane may be used in an amount sufficient to provide a molar ratio of silicon bonded hydroxyl groups (SiOH) in the chain lengthener to alkoxy groups (SiOR) in the other starting materials used to make the composition (SiOH / SiOR) ratio of 1 to 4.(M) Endblocker

[0050] Starting material (M) is and endblocker comprising an M unit, i.e., a siloxane unit of formula R29SiO 1 / 2, where each R29independently represents a monovalent organic group unreactive starting material (B), such as a monovalent hydrocarbon group. Starting material (M) may comprise polyorganosiloxanes endblocked on one terminal end by a triorganosilyl group, e.g., (CHs hSiC)-, and on the other end by a hydroxyl group. Starting material (M) may be a polydiorganosiloxane such as a polydimethylsiloxane. The polydiorganosiloxanes having both hydroxyl end groups and triorganosilyl end groups, may have more than 50 %, alternatively more than 75 %, of the total end groups as hydroxyl groups. The amount of triorganosilyl group in thepolydimethylsiloxane may be used to regulate the modulus of the reaction product prepared by condensation reaction of the composition. Without wishing to be bound by theory, it is thought that higher concentrations of triorganosilyl end groups may provide a lower modulus in certain cured products.(N) Non-reactive Binder

[0051] Starting material (N) is a non-reactive, elastomeric, organic polymer, i.e., an elastomeric organic polymer that does not react with starting materials (A) and (B). Starting material (N) is compatible, i.e., starting material (N) does not form a two-phase system with starting materials (A) and (B). Starting material (N) may have low gas and moisture permeability. Starting material (N) may comprise a polyisobutylene. Alternatively, starting material (N) may comprise butyl rubber. Alternatively, starting material (N) may comprise a styrene-ethylene / butylene-styrene (SEBS) block copolymer, a styrene-ethylene / propylene-styrene (SEPS) block copolymer, or a combination thereof. The amount of starting material (N) may range from 0 parts to 50 parts, alternatively 10 parts to 40 parts, and alternatively 5 parts to 35 parts, based on the weight of the composition.(O) Anti-Aging Additive

[0052] Starting material (O) is an anti-aging additive. The anti-aging additive may comprise an antioxidant, a UV absorber, a UV stabilizer, a heat stabilizer, or a combination thereof. Suitable antioxidants are known in the art and are commercially available. Suitable antioxidants include phenolic antioxidants and combinations of phenolic antioxidants with stabilizers. Phenolic antioxidants include fully sterically hindered phenols and partially hindered phenols. Alternatively, the stabilizer may be a sterically hindered amine such as tetramethyl-piperidine derivatives.Suitable phenolic antioxidants include l,3,5-trimethyl-2,4,6-tris(3,5-di-tert-butyl-4- hydroxybenzyl)benzene; octadecyl 3-(3,5-di-tert-butyl-4-hydroxyphenyl)propi onate; butylated hydroxytoluene (BHT); (i)-a-Tocopherol (vitamin E); and IRGANOX™ 1010 from Ciba Specialty Chemicals, U.S.A. IRGANOX™ 1010 comprises pentaerythritol tetrakis(3-(3,5-di-t-butyl-4- hydroxyphenyl)propionate). Examples of UV absorbers include phenol, 2-(2H-benzotriazol-2-yl)- 6-dodecyl-4-methyl-, branched and linear (TINUVIN™ 571). Examples of UV stabilizers include bis(l ,2,2,6,6-pentamethyl-4-piperidyl) sebacate; methyl l,2,2,6,6-pentamethyl-4-piperidyl / sebacate; and a combination thereof (TINUVIN™ 272). These and TINUVIN™ additives are commercially available from Ciba Specialty Chemicals of Tarrytown, NY, U.S.A. Other UV and light stabilizers are commercially available, and are exemplified by LowLite from Chemtura, OnCap from PolyOne, and Light Stabilizer 210 from E. I. du Pont de Nemours and Company of Delaware, U.S.A.Oligomeric (higher molecular weight) stabilizers may alternatively be used, for example, to minimize potential for migration of the stabilizer out of the composition or the cured productthereof. An example of an oligomeric antioxidant stabilizer (specifically, hindered amine light stabilizer (HALS)) is Ciba TINUVIN™ 622, which is a dimethylester of butanedioic acid copolymerized with 4-hydroxy-2,2,6,6-tetramethyl-l -piperidine ethanol. Heat stabilizers may include iron oxides and carbon blacks, iron carboxylate salts, cerium hydrate, barium zirconate, cerium and zirconium octoates, and porphyrins.

[0053] The amount of starting material (0) depends on various factors including the specific antiaging additive selected and the anti-aging benefit desired. However, the amount of starting material(O) may range from 0 to 5 weight %, alternatively 0.1 % to 4 %, and alternatively 0.5 % to 3 %, based on the weight of the composition.(P) Water Release Agent

[0054] Starting material (P) is a water release agent that releases water over an application temperature range. Starting material (P) is selected such that starting material (P) contains an amount of water sufficient to partially or fully react the composition and such that starting material(P) releases the sufficient amount of water when exposed for a sufficient amount of time to a use temperature (z.e., a temperature at which the composition is used). However, starting material (P) binds the water sufficiently to prevent too much water from being released during the method for making the composition and during storage of the composition. For example, starting material (P) binds the water sufficiently during compounding of the composition such that sufficient water is available for condensation reaction of the composition during or after the application process in which the composition is used. This “controlled release” property also may provide the benefit of ensuring that not too much water is released too rapidly during the application process, since this may cause bubbling or voiding in the reaction product formed by condensation reaction of the composition. Precipitated calcium carbonate may be used as starting material (P) when the application temperature ranges from 80 °C to 120 °C, alternatively 90 °C to 110 °C, and alternatively 90 °C to 100 °C. However, when the composition is prepared on a continuous (e.g., twin-screw) compounder, the starting materials may be compounded at a temperature 20 °C to 30 °C above the application temperature range for a short amount of time. Therefore, starting material (P) is selected to ensure that not all of the water content is released during compounding; however starting material (P) releases a sufficient amount of water for condensation reaction of the composition when exposed to the application temperature range for a sufficient period of time.

[0055] Examples of suitable water release agents are exemplified by metal salt hydrates, hydrated molecular sieves, and precipitated calcium carbonate, which is available from Solvay under the trademark WINNOFIL™ SPM. The water release agent selected can depend on various factors including the other starting materials selected for the composition, including catalyst type andamount, if present; and the process conditions during compounding, packaging, and application. In a twin-screw compounder, residence time may be less than a few minutes, typically less than 1 to 2 minutes. The starting materials are heated rapidly because the surface area / volume ratio in the barrels and along the screw is high and heat is induced by shearing the starting materials. How much water is removed from starting material (P) depends on the water binding capabilities, the temperature, the exposure time (duration), and the level of vacuum used to strip the composition passing through the compounder. Without wishing to be bound by theory, it is thought that with a twin screw compounding temperature of 120 °C there would remain enough water on the precipitated CaCO i to cause the composition to react by condensation reaction over a period of 1 to 2 weeks at room temperature when the composition has been applied at 90 °C.

[0056] The amount of starting material (P) in the composition depends on various factors including the selection of starting materials (A) and (B) and whether any additional starting materials are present, however the amount of starting material (P) may range from 5 to 30 parts based on the weight of the composition.

[0057] Without wishing to be bound by theory, it is thought the composition can be heated to an application temperature to allow for the heat to liberate the water, and the water would react with hydrolyzable groups on starting material (B), e.g., when (B) the aldehyde-functional organosilicon compound also has alkoxy groups, to further cure the composition. By-products such as alcohols and / or water left in the composition may be bound by a drying agent, thereby allowing the reaction to proceed toward completion.(Q) Colorant

[0058] Starting material (Q) is a colorant, e.g., an inorganic pigment or an organic dye. For purposes of this application, the term ‘colorant’ includes any starting material used to impart color to a reaction product of a composition described herein. The amount of colorant depends on various factors including the type of colorant selected and the desired degree of coloration of the reaction product. For example, the composition may comprise 0 to 20 %, alternatively 0.001 % to 5 %, of a colorant based on the weight of all starting materials in the composition.

[0059] Examples of suitable colorants include indigo, titanium dioxide Stan-Tone 50SP01 Green (which is commercially available from PolyOne) and carbon black, which is available from various sources such as Calgon Carbon Corporation of Pittsburgh, Pennsylvania, USA.(R) Rheological Additive

[0060] The composition may optionally further comprise up to 5 %, alternatively 1 % to 2 % based on the weight of the composition of starting material (R) a rheological additive for modifying rheology of the composition. Rheological additives are known in the art and are commerciallyavailable. Examples include polyamides, e.g., Polyvest, which is commercially available from Evonik, Disparlon from King Industries, Kevlar Fibre Pulp from Du Pont, Rheospan from Nanocor, and Ircogel from Lubrizol. Other suitable rheological additives include microcrystalline waxes, polyamide waxes; hydrogenated castor oil derivatives; and metal soaps such as calcium stearate, aluminum stearate and barium stearate, and combinations thereof. Without wishing to be bound by theory, it is thought that starting material (R) acts as a process aid that improves flow properties while allowing rapid green strength development (z.e., a strong increase in viscosity, corresponding to increase in the load carrying capability of a seal prepared from the composition, with a temperature drop) upon cooling the composition a few degrees, for example, after the composition is applied to a substrate.

[0061] The amount of starting material (R) depends on various factors including the specific rheological additive selected and the selections of the other starting materials of the composition. However, the amount of starting material (R) may range from 0 parts to 20 parts, alternatively 1 part to 15 parts, and alternatively 1 part to 5 parts based on the weight of the composition.(S) Vehicle

[0062] A vehicle e.g., a solvent and / or diluent) may be used in the composition. The vehicle may facilitate flow of the composition and introduction of certain starting materials, such as silicone resin or catalyst, when used. Vehicles used herein are those that help fluidize the starting materials of the composition but essentially do not react with any of these starting materials. Vehicles may be selected based on solubility the starting materials in the composition and volatility. The solubility refers to the vehicle being sufficient to dissolve and / or disperse starting materials of the composition. Volatility refers to vapor pressure of the vehicle. If the vehicle is too volatile (having too high vapor pressure) bubbles may form in the composition at the application temperature, and the bubbles may cause cracks or otherwise weaken or detrimentally affect properties of the cured product of the composition. However, if the vehicle is not volatile enough (too low vapor pressure) the vehicle may remain as a plasticizer in the reaction product of the composition, or the amount of time for the reaction product to develop physical properties may be longer than desired.

[0063] Suitable vehicles include polyorganosiloxanes with suitable vapor pressures, such as hexamethyldisiloxane, octamethyltrisiloxane, hexamethylcyclotrisiloxane, and other low molecular weight polyorganosiloxanes, such as 0.5 to 1.5 centiStoke (cSt) XIAMETER™ PMX 200 Fluids and DOWSIL™ OS FLUIDS, which are commercially available from Dow Silicones Corporation of Midland, Michigan, U.S.A.

[0064] Alternatively, the vehicle may be an organic solvent. The organic solvent can be an alcohol such as methanol, ethanol, isopropanol, butanol, or n-propanol; a ketone such as acetone,methylethyl ketone, or methyl isobutyl ketone; an aromatic hydrocarbon such as benzene, toluene, or xylene; an aliphatic hydrocarbon such as heptane, hexane, or octane; a glycol ether such as propylene glycol methyl ether, dipropylene glycol methyl ether, propylene glycol n-butyl ether, propylene glycol n-propyl ether, or ethylene glycol n-butyl ether, a halogenated hydrocarbon such as dichloromethane, 1,1,1 -trichloroethane or methylene chloride; chloroform; dimethyl sulfoxide; dimethyl formamide, acetonitrile; tetrahydrofuran; white spirits; mineral spirits; naphtha; n-methyl pyrrolidone; or a combination thereof

[0065] The amount of vehicle can depend on various factors including the type of vehicle selected and the amount and type of other starting materials selected for the composition. However, the amount of vehicle may range from 1 % to 99%, alternatively 2 % to 50 %, based on the weight of the composition.(T Tackifying Agent

[0066] The composition may optionally further comprise starting material (T) a tackifying agent. The tackifying agent may comprise an aliphatic hydrocarbon resin such as a hydrogenated polyolefin having 6 to 20 carbon atoms, a hydrogenated terpene resin, a rosin ester, a hydrogenated rosin glycerol ester, or a combination thereof. Tackifying agents are commercially available.(U) Corrosion Inhibitor

[0067] The composition may optionally further comprise starting material (U), a corrosion inhibitor. Examples of suitable corrosion inhibitors include benzotriazole , mercaptabenzotriazole and commercially available corrosion inhibitors such as 2,5-dimercapto-l,3,4-thiadiazole derivative (CUVAN™ 826) and alkylthiadiazole (CUVAN™ 484) from R. T. Vanderbilt of Norwalk, Connecticut, U.S.A. When present, the amount of starting material (U) may range from 0.05 % to 0.5 % based on the weight of the composition.(V) Encapsulating Agent

[0068] Starting material (V) is an optional encapsulating agent that may be used, for example, to encapsulate one or more of the other starting materials so as to prepare a one part composition. For example, one or both of starting materials (A) and (B) may be encapsulated in the encapsulating agent before incorporation into the composition.(W) Condensation Reaction Catalyst

[0069] The composition described herein may optionally further comprise (W) a condensation reaction catalyst. Condensation reaction catalysts include metal and non-metal catalysts. Metal catalysts may include tin, titanium, zirconium, lead, iron, cobalt, antimony, manganese, bismuth and / or zinc compounds. For example, the condensation reaction catalyst may comprise organotin compounds such as organic tin esters and organic tin chelate complexes, organic titanium catalystssuch as organic titanate esters and organic titanium chelate complexes. Exemplary organotin compounds include dibutyltindilaurate, dibutyltindiacetate, dibutyltindimethoxide, tinoctoate, isobutyltintriceroate, dibutyltin oxide, dibutyltin bis-diisooctylphthalate, bistripropoxysilyl dioctyltin, dibutyltin bis-acetylacetone, silylated dibutyltin dioxide, carbomethoxyphenyl tin tris- uberate, isobutyltintriceroate, dimethyltin dibutyrate, dimethyltin di- neodecanoate (DMTDN), dibutyltin dibenzoate, tin oleate, tin naphthenate, butyltintri-2-ethylhexylhexoate, and tinbutyrate. Alternatively, non-metal catalysts may include tetramethylguanidylpropyltrimethoxysilane and tetramethylguanidylpropyl-tristrimethylsiloxysilane. Exemplary organotitanium compounds include tetraisopropoxy titanium. The exact amount of catalyst depends on various factors including the type of catalyst selected, and the hydrolyzable group content of the starting materials in the composition, however, the amount of (W) condensation reaction catalyst may be 0.05% to 3%, based on weight of all starting materials in the composition.

[0070] When selecting starting materials for the composition described above, there may be overlap between types of starting materials because certain starting materials described herein may have more than one function. For example, certain alkoxysilanes may be useful as filler treating agents, crosslinkers, drying agents, and / or as adhesion promoters, certain fatty acid esters may be useful as plasticizers and may also be useful as filler treating agents, carbon black may be useful as a pigment, a flame retardant, and / or a filler, and nonreactive polydiorganosiloxanes such as polydimethylsiloxanes may be useful as extenders and as solvents.

[0071] One skilled in the art would recognize that the composition described above may be formulated to be cured in the absence of organotin compounds, e.g., as described above for starting material (W). The examples below show that the composition may cure at RT in 30 minutes to 4 days, even in the absence of (W) the condensation reaction catalyst. This is true even if (C) the crosslinker is not present. Without wishing to be bound by theory, it is thought that the reaction of the amino moiety of (A) (the aminosiloxane ester copolymer) and the aldehyde moiety of starting material (B) produces water as a by-product, which may enhance cure of the composition, such as when (B) the aldehyde-functional organosilicon compound and / or an additional starting material with alkoxy groups is used in the composition.Method of Making the Composition

[0072] The composition described above may be prepared as a one-part composition, for example, by combining all starting materials by any convenient means, such as mixing. For example, a one-part composition may be made by optionally combining e.g. , premixing) one or both of starting materials (A) and (B) with (V) the encapsulating agent and / or (D) the drying agent before combining (A) and (B). One or more of the optional additional starting materials may beadded to the composition at any desired stage. A final mixing step may be performed under substantially anhydrous conditions, and the resulting compositions are generally stored under substantially anhydrous conditions, for example in sealed containers, until ready for use.

[0073] Alternatively, the composition may be prepared as a multiple part (e.g. , 2 part) composition. In this instance, starting materials (A) and (B) are stored in separate parts, and the parts are combined shortly before use of the composition. For example, a two-part curable composition may be prepared by combining starting materials comprising (A) and one or more of (C) to (W) to form a first part, and combining starting materials comprising (B) and one or more of (C) to (W) to form a second part, by any convenient means such as mixing. The starting materials may be combined at ambient temperature and under ambient or anhydrous conditions. The two parts may be combined by any convenient means, such as mixing, shortly before use. The two parts may be combined in equal amounts, or in an amount of first part to second part of 10: 1 to 10: 1. The composition will then cure under ambient conditions, e.g. at RT. Exposure to atmospheric moisture may facilitate cure, when one of the starting materials has hydrolyzable groups. The composition may be, for an example, a room temperature vulcanizable (RTV) sealant composition.

[0074] The equipment used for mixing the starting materials is not specifically restricted. Examples of suitable mixing equipment may be selected depending on the type and amount of each starting material selected. For example, agitated batch kettles may be used for relatively low viscosity compositions, such as compositions that would react to form gums or gels. Alternatively, continuous compounding equipment, e.g., extruders such as twin screw extruders, may be used for more viscous compositions and compositions containing relatively high amounts of particulates. Exemplary methods that can be used to prepare the compositions described herein include those disclosed in, for example, US Patent Publications US20090291238 to Scott et al., and US20080300358 to Cook et al.EXAMPLES

[0075] The following examples are provided to illustrate the invention to those skilled in the art and are not to be interpreted as to limit the scope of the invention set forth in the claims. The starting materials used in these examples are summarized below in Table 1. In the following examples, tensile properties were measured according to ASTM D412, and hardness was measured according to ASTM D2240.Table 1 - Starting Materials

[0076] In this Reference Example 1, a curable polyorganosiloxane composition was prepared and cured as follows: Starting materials A-l and B-l (Table 1), in amounts described below, were combined in a dental mixer and mixed at 3000 rpm for 10 seconds. The resulting mixture was then poured into a plastic weigh pan and left to cure into a slab under ambient conditions. Reactions A to E were performed in this manner, as follows.

[0077] In this Reaction A, the aminosiloxane ester copolymer (A-l) had subscript a = 44 and subscript b = 5. Five grams of each starting material (A-l) and (B-l) in Table 1, above, were combined. The resulting mixture was no longer flowable after 1 minute and only slightly tacky to the touch after 10 minutes. After 24 hours the slab was removed from the pan, and dog bone shaped samples were cut for tensile elongation as well as Shore A and Shore 00 hardness testing.

[0078] In this Reaction B, the aminosiloxane ester copolymer (A-l) had subscript a = 84 and subscript b = 5. Five grams of each starting material (A-l) and (B-l) in Table 1, above, were combined. The resulting mixture was no longer flowable after 1 minute and only slightly tacky to the touch after 10 minutes. After 24 hours the slab was removed from the pan, and dog bone shaped samples were cut for tensile elongation as well as Shore A and Shore 0 hardness.

[0079] In this Reaction B2, the aminosiloxane ester copolymer (A-l) had subscript a = 84 and subscript b = 5. 6.67 grams of this aminosiloxane ester copolymer, and 3.33 grams of starting material (B-l) in Table 1, were combined. The resulting mixture was no longer flowable after 2minutes and only slightly tacky to the touch after 10 minutes. After 24 hours the slab was removed from the pan, and dog bone shaped samples were cut for tensile elongation as well as Shore A and Shore 0 hardness.

[0080] In this Reaction C, the aminosiloxane ester copolymer had subscript a = 16 and subscript b = c.a. 5. Five grams of each starting material were combined. After 24 hours the resulting mixture still had not cured.

[0081] In this Reaction D, the aminosiloxane ester copolymer had subscript a = 44, and subscript b = ca. 2. Five grams of each starting material were combined. The resulting mixture was no longer flowable after 4 minutes and tacky to the touch after 14 minutes. After 24 hours the slab was removed from the pan, and dog bone shaped samples were cut for tensile elongation as well as Shore A and Shore 0 hardness.

[0082] In this Reaction E, the aminosiloxane ester copolymer had subscript a = 30 and subscript b = ca. 2. 3.40 grams copolymer and 3.40 grams dialdehyde were combined. The resulting mixture was no longer flowable after 2 minutes and only slightly tacky to the touch after 10 minutes. After 24 hours the slab was removed, and dog bone shaped samples were cut for tensile elongation as well as Shore A and Shore 0 hardness.

[0083] In this Reference Example 2, Starting materials A-l and either B-2 or B-3 (Table 1), in amounts described below, were combined in a 40 mL glass vial and manually stirred using a plastic pipette. Reactions F, G and H were performed in this manner, as follows.

[0084] In this Reaction F, (A-l) the aminosiloxane ester copolymer had subscript a = 0 and subscript b = 2. 1.03 grams copolymer (A-l) and 0.60 grams dialdehyde (B-2) were combined. Upon the addition of (B-2), the mixture was stirred manually for 10 s using a plastic pipette which resulted in the formation of a cured material.

[0085] In this Reaction G, (A-l) the aminosiloxane ester copolymer had subscript a = 0 and subscript b = 2. 1.02 grams copolymer (A-l) and 0.14 grams dialdehyde (B-3) were combined. Upon the addition of (B-3), the mixture was stirred manually for 10 s using a plastic pipette. At this time, the sample was still flowable. After 24 hours the resulting mixture still had not cured.

[0086] In this Reaction H, (A-l) the aminosiloxane ester copolymer had subscript a = 0 and subscript b = 2. 0.51 grams copolymer (A-l) and 3.21 grams dialdehyde (B-3) were combined. Upon the addition of (B-3), the mixture was stirred manually for 10 s using a plastic pipette resulting in the formation of solid and some flowable liquid. After 4 hours, the entire sample had solidified and was no longer flowable.

[0087] In this Reaction I, (A-l) the aminosiloxane ester copolymer had subscript a = 0 and subscript b = 2. 0.50 grams copolymer (A-l) and 5.11 grams dialdehyde (B-3) were combined.Upon the addition of (B-3), the mixture was stirred manually for 10 s using a plastic pipette resulting in the formation of solid and some flowable liquid. After 4 hours, the sample was not fully cured. After 66 h, the entire sample had solidified and was no longer flowable.Table 2 - Summary of Starting Materials Used and Hardness Test Results

[0088] In Table 2, NH / CHO mole ratio means ratio of the molar amount of amine (N-H) moieties divided by the molar amount of aldehyde moieties. Samples A, B, B2, D, E, F and H were prepared and cured in less than 24 hours. Sample I cured in less than 66 hours. Samples C and G were prepared and did not cure after 24 hours. The hardness was not tested on samples C, F, G, H, and I.Table 2 (continued) - Tensile Elongation Test ResultsTable 2 (continued).Table 3 Hardness Test ResultsIndustrial Applicability

[0089] The composition described herein provides the benefit of not including toxic, volatile aldehydes over previously disclosed silicone sealants that use these small molecule organic aldehydes in combination with aminopropyl modified silicone polymers. The composition prepared as described herein does not require a toxic volatile aldehyde delivered in water. Because both the amino-functional and the aldehyde-functional starting materials used herein as starting materials (A) and (B) are organosilicon compounds, compatibility of the composition described herein maybe improved over previously disclosed systems. In addition, the composition described herein does not require a catalyst to cure. Said composition may, therefore, be free of conventional condensation reaction catalysts, such as organotin compounds.

[0090] The composition described herein may also provide the benefit of having tunable properties. The properties such as cure speed of the composition, and the properties such as modulus of the cured product of said composition, may be controlled by varying the amount of aminosiloxane ester copolymer and aldehyde- functional organosilicon compound in the composition. It is not necessary to provide an amine - rich system to avoid unreacted aldehyde because the composition of this invention does not need to include a volatile organic aldehyde, such as formaldehyde.

[0091] Another benefit of the composition described herein may be improved deep section curing over systems disclosed previously. Without wishing to be bound by theory, it is thought that the water generated as a side product of the curing reaction (of the amino-functional groups and the aldehyde-functional groups) will further facilitate hydrolysis and condensation reaction of alkoxy groups bonded to silicon atoms in the starting materials used to make the composition.Definitions and Usage of Terms

[0092] 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 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 A, below.Table A - Abbreviations

Claims

Claims:

1. A curable polyorganosiloxane composition comprises:A) an aminosiloxane ester copolymer comprising formulawhere each R1is an independently selected monovalent hydrocarbon group of 1 to 12 carbon atoms, each REis an independently selected amino-functional group of formula H2N-RA-, each RAis an independently divalent hydrocarbon group of 1 to 12 carbon atoms, each R2is independently selected from the group consisting of hydrogen and methyl, each RDis an independently selected divalent hydrocarbon group of 2 to 20 carbon atoms, each subscript a independently has a value such that 0 < a < 150; and subscript b has a value such that 1 < b < 100;B) an aldehyde-functional organosilicon compound, having per molecule, a silicon bonded aldehyde group of formuladivalent hydrocarbon group free of aliphatic unsaturation that has 2 to 8 carbon atoms; with the proviso that A) the aminosiloxane ester copolymer and B) the aldehyde- functional organosilicon compounds are present in amounts such that a molar ratio of N-H moieties from A) to aldehyde moieties from B) (NH / CHO ratio) is 0.25 / 1 to < 4.22 / 1.

2. The composition of claim 1, where in A) the aminosiloxane ester copolymer each R1is an independently selected alkyl group of 1 to 12 carbon atoms, each REis the amino-functional group of formula H2N-RA-, each RAis an independently selected alkylene group of 2 to 5 carbon atoms, each R2is hydrogen, each RDis an independently selected alkylene group of 2 to 12 carbon atoms,30 < a < 84, and2 < b < 5.

3. The composition of claim 1 or claim 2, where B) the aldehyde functional organosilicon compound is a silane of formula: RAldxSiR4(4-x), where each RAldis the aldehyde group of formulathe divalent hydrocarbon group free of aliphatic unsaturation that has 2 to 8 carbon atoms; each R4is independently selected from the group consisting of an alkyl group of 1 to 18 carbon atoms, an aryl group of 6 to 18 carbon atoms, an acyloxy group of 2 to 18 carbon atoms, and an hydrocarbonoxy-functional group of 1 to 18 carbon atoms; and subscript x is 1 to 4.

4. The composition of claim 1 or claim 2, where the aldehyde-functional organosilicon compound is an aldehyde-functional polyorganosiloxane of unit formula:(R43SiOi / 2)a(R42RAldSiOi / 2)b(R42SiO2 / 2)c(R4RAldSiO2 / 2)d(R4SiO3 / 2)e(RAldSiO3 / 2)f(SiO4 / 2)g(ZOi / 2)h; where each RAldis the aldehyde group of formulathe divalent hydrocarbon group free of aliphatic unsaturation that has 2 to 8 carbon atoms; each R4is independently selected from the group consisting of an alkyl group of 1 to 18 carbon atoms, an aryl group of 6 to 18 carbon atoms, and an hydrocarbonoxy group of 1 to 18 carbon atoms; each Z is independently selected from the group consisting of a hydrogen atom and R5, where each R5is independently selected from the group consisting of alkyl groups of 1 to 18 carbon atoms and aryl groups of 6 to 18 carbon atoms; subscripts a, b, c, d, e, f, and g represent numbers of each unit in the unit formula and have values such that subscript a > 0, subscript b > 0, subscript c > 0, subscript d > 0,subscript e > 0, subscript f > 0, subscript g > 0, with the provisos that a quantity (b + d + f) > 1, and10,000 > (a + b + c + d + e + f + g) > 2; and subscript h has a value such that 0 < h / (e + f + g) < 1.5.

5. The composition of claim 4, where the aldehyde-functional polyorganosiloxane comprises unit formula: (R43SiOi / 2)a(RAldR42SiO i / 2)b(R42SiO2 / 2)c(RAldR4SiO2 / 2)d, where each R4is alkyl or aryl; each RAldis the aldehyde group of formulathe divalent hydrocarbon group free of aliphatic unsaturation that has 2 to 8 carbon atoms; subscript a is 0, 1, or 2; subscript b is 0, 1, or 2; a quantity (a + b) has an average value of 2; subscript c is 0 or greater, subscript d is 0 or greater; a quantity (b + d) is 1 or greater; and a quantity (c + d) is 1 to 180.

6. The composition of any one of claims 3, 4, or 5, where each R4is alkyl, and each RAldis propyl aldehyde, butyl aldehyde or heptyl aldehyde.

7. The composition of claim 6, where each R4is methyl, and each RAldis propyl aldehyde.

8. The composition of any one of claims 1 to 7, further comprising an additional starting material selected from the group consisting of (C) a condensation reaction catalyst; (D) a crosslinker; (E) an extender, a plasticizer, or a combination thereof; (F) a filler; (G) a filler treating agent; (H) a biocide; (J) a flame retardant; (K) a surface modifier; (L) a chain lengthener; (M) an endblocker;(N) a nonreactive binder; (O) an anti-aging additive; (P) a water release agent; (Q) a colorant; (R) a rheological additive; (S) a vehicle; (T) a tackify ing agent; (U) a corrosion inhibitor; (V) anencapsulating agent; and a combination of two or more thereof.

9. The composition of any one of claims 1 to 8, wherein the composition is free of organotin compounds.

10. A method for preparing the composition of any one of claims 1 to 9, wherein the method comprises mixing starting materials (A) and (B).

11. A kit for making a cured polyorganosiloxane, wherein the kit comprises:1) the composition of any one of claims 1 to 9, and2) instructions for curing the composition.

12. The composition of any one of claims 1 to 9 or the kit of claim 11, where the composition is a multiple part composition, and starting material (A) and starting material (B) are stored in separate parts.

13. A method for preparing a cured polyorganosiloxane, wherein the method comprises: exposing the composition of any one of claims 1 to 9 to water, thereby preparing a reaction product comprising the cured polyorganosiloxane.

14. The cured polyorganosiloxane prepared by the method of claim 13.

15. Use of the cured polyorganosiloxane of claim 14 as a sealant.

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