Curable polyorganosiloxane compositions comprising phosphonium

Abstract

A composition containing a phosphonium catalyst, a polyorganohydrosiloxane, and a hydrocarbyloxy-functional organosilicon compound. The composition may be cured using a method that includes heating. The compositions and methods are useful for preparing polyorganosiloxane products, such as coatings, adhesives, elastomers, and foams.

Description

[0001] CROSS-REFERENCE TO RELATED APPLICATIONS

[0002] This application claims the benefit under 35 USC §119(e) of U.S. Provisional Patent Application Serial No. 63 / 352,312, filed on June 15, 2022. U.S. Provisional Patent Application Serial No. 63 / 352,312 is hereby incorporated by reference. Technical Field

[0003] The invention provides a curable polyorganosiloxane composition and a method for preparing and curing the same. More specifically, the curable polyorganosiloxane composition comprises a phosphonium catalyst, a polyorganohydrogensiloxane and a hydrocarbyloxy-functional organosilicon compound. Background Art

[0004] It is known that silyl hydride (Si-H) and silyl ether (Si-OR, where R is, for example, methyl) moieties react in the presence of a strong Lewis acid catalyst to produce siloxanes and RH, which is known as the Piers-Rubinsztajn ("PR") reaction. It may be desirable to use the PR reaction to cure siloxanes in coatings, adhesives, elastomers, and foaming applications. However, these reactions are very rapid. Therefore, PR reaction systems are typically two-component systems in which the catalyst is kept separate from the Si-OR until the reaction is desired. It is desirable that the PR type reaction components can be stored together in a single component system in a manner that provides shelf stability for storage but has a way to trigger the PR type reaction when it is desired to cure the system. There are systems in which the Lewis acid catalyst is complexed with an ultraviolet (UV) sensitive blocker that prevents the catalyst from achieving a PR type reaction until irradiated with UV light. However, for storage stability, such systems need to be stored in the dark and must be exposed to UV light to initiate curing. Upon exposure to UV light, the release of the Lewis acid is often slow, resulting in a reaction that is slowly initiated upon exposure to UV light. The use of UV blocking Lewis acids requires a triggering film so that UV light can effectively penetrate into the composition and achieve high surface area exposure. Therefore, UV blocking of Lewis acids has disadvantages when compositions that do not need to be protected from UV light exposure are desired before Lewis acid catalyzed reactions can begin, reactions can start quickly (fast release of Lewis acid), and / or reactions in the bulk composition can be quickly triggered. Summary of the invention

[0005] A curable polyorganosiloxane composition (composition) comprising a mixture of: (A) a phosphonium catalyst; (B) a polyorganohydrogensiloxane; and (C) a hydrocarbyloxy-functional organosilicon compound. Methods for preparing and curing the composition are provided. DETAILED DESCRIPTION

[0006] The composition described above may be a one-component composition. The composition comprises a mixture of: (A) a phosphonium catalyst; (B) a polyorganohydrogensiloxane; and (C) a hydrocarbyloxy-functional organosilicon compound. The phosphonium catalyst comprises a cationic salt of phosphorus and a non-coordinating anion.

[0007] Starting material (A) Phosphonium catalyst

[0008] The starting material (A) used herein is a phosphonium catalyst comprising (i) a tetravalent monocation of phosphorus and (ii) a non-coordinating anion. The tetravalent monocation of phosphorus is a Lewis acidic phosphonium cation of formula (i-1):

[0009] [PR 1 3R 2 ] + , where each R 1 is an independently selected halogenated aryl group, and each R 2 are independently selected from the group consisting of halogen atoms and electron withdrawing groups. 1 Can have the following formula: Each R 8 independently selected from H, X and a group of formula -CX3, wherein each X is an independently selected halogen; provided that at least one R 8 is not H. Each X may be independently selected from chlorine (Cl) or fluorine (F). Alternatively, each X may be F. Alternatively, each R 8 may be independently selected from the group consisting of H, Cl, F and a group of formula -CF3, provided that at least one R 8 It is Cl, F or -CF3.

[0010] R 2 The halogen atom of R may be selected from the group consisting of bromine (Br), Cl and F; alternatively, Cl and F. Alternatively, R 2 The halogen atom may be F. 2 The electron withdrawing group may include an atom with an electronegativity ≥ 2.5 bonded to P, such as carbon (C) or oxygen (O). Alternatively, the electron withdrawing group may have the formula -CX'3, wherein X' is a halogen atom selected from Br, Cl or F; alternatively, Cl or F; and alternatively, F. Alternatively, R 2 The electron withdrawing group may have the formula -CF3. 2 The electron withdrawing group may have the formula -OR 9 , where R 9 is an alkyl group or an aryl group. 9The alkyl group of may be linear, branched, cyclic or a combination of two or more thereof. Examples of alkyl groups include methyl, ethyl, 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 examples of alkyl groups include cycloalkyl groups such as cyclopropyl, cyclobutyl, cyclopentyl and cyclohexyl. Applicable to R 9 The aryl group may be monocyclic or polycyclic and may have a pendant hydrocarbon group. 9 The aryl groups of include phenyl, tolyl, xylyl and naphthyl, and also include aralkyl groups such as benzyl, 1-phenylethyl and 2-phenylethyl. 9 The aryl group may be monocyclic, such as phenyl, tolyl or benzyl; alternatively, R 9 The aryl group of may be phenyl.

[0011] Alternatively, in formula (i-1), each R 1 Alternatively, in formula (i-1), R 2 Alternatively, (i) the tetravalent monocation of phosphorus may have the formula: [P(C6F5)3F] + .

[0012] In addition to (i) a tetravalent monocation of phosphorus, the (A) phosphonium catalyst further comprises (ii) a non-coordinating anion as described above. The non-coordinating anion may have a charge that is non-localized on the surface of the anion, rather than being localized at a specific atom. Suitable non-coordinating anions include those of the formula [CF3SO3] - The trifluoromethanesulfonate (trifluoromethanesulfonate) and the formula [BR 3 4] - anion, where each R 3 Independently selected from the group consisting of a monovalent hydrocarbon group and a monovalent halogenated hydrocarbon group. The monovalent hydrocarbon group can be an alkyl group or an aryl group. The monovalent halogenated hydrocarbon group can be an alkyl group or an aryl group in which one or more hydrogen atoms have been replaced by F, Cl or Br.

[0013] Applicable to R 3 The alkyl group of R may be linear, branched, cyclic, or a combination of two or more thereof. 3Examples of the alkyl groups are methyl, ethyl, 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 chain isomers having 5 to 18 carbon atoms), and examples of the alkyl groups are cycloalkyl groups such as cyclopropyl, cyclobutyl, cyclopentyl and cyclohexyl. Suitable haloalkyl groups include chlorinated alkyl groups such as chloromethyl and chloropropyl groups; fluorinated alkyl groups such as fluoromethyl, difluoromethyl, trifluoromethyl, 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.

[0014] Applicable to R 3 The aryl group may be monocyclic or polycyclic and may have a pendant hydrocarbon group. 3 The aryl groups of include phenyl, tolyl, xylyl and naphthyl, and also include aralkyl groups such as benzyl, 1-phenylethyl and 2-phenylethyl. 3 The aryl group may be monocyclic, such as phenyl, tolyl or benzyl; alternatively, R 3 The aryl group of R may be phenyl. 3 The halogenated aryl group may be as described above for R 1 The halogenated aryl group.

[0015] Alternatively, the non-coordinating anion may be fully saturated, with no free valence electrons participating in forming covalent or coordination bonds with the phosphonium. A fully saturated anion may have the formula [BR 3 4] - , where each R 3 is independently selected from the group consisting of a monovalent hydrocarbon group and a monovalent halogenated hydrocarbon group, as described above. 3 Alternatively, the anion may have the formula [B(C6F5)4] - .

[0016] Alternatively, the (A) catalyst may have the formula:

[0017] The starting material (A) can be prepared by methods known in the art, for example, the method disclosed in Science, 2013, Vol. 341, pp. 1374-1377, by changing a suitable starting material. The starting material (A) used herein can be any one of the above catalysts, or a combination of two or more of the above catalysts.

[0018] The compositions described herein include a sufficient amount of (A) catalyst to cure the composition. The exact amount of (A) catalyst depends on various factors, including the choice of (B) polyorganohydrogensiloxane, the SiH content, and the choice and amount of (C) hydrocarbyloxy-functional organosilicon compound. However, the composition may include sufficient catalyst to provide a tetravalent monocation of phosphorus at a concentration of at least 1 ppm, alternatively at least 2 ppm, alternatively at least 5 ppm; while the amount may be up to 1,000 ppm, alternatively up to 500 ppm, alternatively up to 100 ppm, and alternatively up to 50 ppm; each based on the combined weight of the starting materials (A), (B), and (C). Alternatively, the amount of (A) phosphonium catalyst may be from 1 ppm to 1,000 ppm, alternatively from 2 ppm to 500 ppm, alternatively from 5 ppm to 100 ppm, and alternatively 10 ppm; based on the combined weight of (A) catalyst, (B) polyorganohydrogensiloxane, and (C) hydrocarbyloxy-functional organosilicon compound in the composition.

[0019] Starting material (B) polyorganohydrogensiloxane

[0020] The compositions described herein also include (B) a polyorganohydrogensiloxane. The polyorganohydrogensiloxane has at least one Si-H moiety per molecule. Alternatively, the polyorganohydrogensiloxane may have more than one Si-H moiety per molecule. Polyorganohydrogensiloxanes having multiple Si-H moieties (e.g., 2 or more, alternatively 3 or more) per molecule can be used as crosslinking agents in the compositions described herein because they are able to react with multiple alkoxy functional moieties of the starting material (C).

[0021] The polyorganohydrogensiloxane may include HR 4 2SiO 1 / 2 , R 4 3SiO 1 / 2 , HR 4 SiO 2 / 2 , R 4 2SiO 2 / 2 , R 4 SiO 3 / 2 ,HSiO 3 / 2 and SiO 4 / 2 Units consisting of two or more siloxane units; wherein each R 4is an independently selected monovalent hydrocarbon group free of aliphatic unsaturated groups; provided that at least one unit per molecule contains a Si-H moiety (i.e., there is HR in the polyorganohydrogensiloxane 4 2SiO 1 / 2 , HR 4 SiO 2 / 2 and HSiO 3 / 2 The monovalent hydrocarbon group free of aliphatic unsaturated groups may be an alkyl group or an aryl group, as described above for R 3 Alternatively, each R 4 Can be an independently selected alkyl group. Alternatively, each R 4 may be independently selected from the group consisting of methyl and phenyl. Alternatively, each R 4 It may be methyl.

[0022] Alternatively, (B) polyorganohydrogensiloxane may be linear or cyclic. For example, (B) polyorganohydrogensiloxane may be a polyorganohydrogensiloxane comprising unit formula (B-1): (HR 4 2SiO 1 / 2 ) g (R 4 3SiO 1 / 2 ) h (R 4 2SiO 2 / 2 ) i (HR 4 SiO 2 / 2 ) j A linear polydiorganohydrogensiloxane, wherein R 4As described above, and the values ​​of the subscripts g, h, i, and j are such that g≥0, h≥0, the amount (g+h)=2, i≥0, j≥0, and the amount (g+j)≥1, and the amount (i+j) is 0 to 2,000. The amount (i+j) may be 2,000 or less, alternatively 1,000 or less, alternatively 750 or less, alternatively 500 or less, alternatively 250 or less, alternatively 100 or less, and alternatively 50 or less; at the same time, the amount (i+j) may be 0 or more, alternatively 1 or more, alternatively 2 or more, alternatively 3 or more, alternatively 4 or more, alternatively 5 or more, alternatively 10 or more, alternatively 15 or more, alternatively 20 or more. Alternatively, (i+j) may be 0 to 1,000; alternatively 1 to 500; alternatively 2 to 250, and alternatively 3 to 100. Alternatively, (i+j) may be 1 to 100. Alternatively, (i+j) may be 2 to 50. Alternatively, (i+j) may be 5 to 25. Alternatively, when g=0 and h=2, j≥1 (alternatively ≥2). Alternatively, g may be 1, and h may be 1. Alternatively, g may be 2, and h may be 0. Alternatively, i may be 0 to 5, alternatively 1 to 4, alternatively 2 to 4, and alternatively 3 to 3.5. Alternatively, i may be 5 to 25. Alternatively, j may be 1 to 10, alternatively 2 to 9, alternatively 3 to 8, alternatively 4 to 7, and alternatively 5 to 6. Alternatively, when g>0, then j may be 0.

[0023] Examples of linear polydiorganohydrogensiloxanes suitable for use herein are:

[0024] (i) α,ω-dimethylhydrogensiloxy-terminated poly(dimethylsiloxane / methylhydrogensiloxane),

[0025] (ii) α,ω-dimethylhydrogensiloxy-terminated polymethylhydrogensiloxane,

[0026] (iii) α,ω-trimethylsilyloxy-terminated poly(dimethylsiloxane / methylhydrogensiloxane),

[0027] (iv) α,ω-trimethylsilyloxy-terminated polymethylhydrogensiloxane, and

[0028] (v) poly(dimethylsiloxane / methylhydrogensiloxane) terminated with α-dimethylhydrogensiloxy-ω-trimethylsiloxy,

[0029] (vi) polymethylhydrogensiloxane terminated with α-dimethylhydrogensiloxy-ω-trimethylsiloxy,

[0030] (vii) a combination of two or more thereof.

[0031] Alternatively, the polyorganohydrogensiloxane may be cyclic. The cyclic polyorganohydrogensiloxane may include unit formula (B-2): (R 4 2SiO 2 / 2 ) u (R 4 HSiO 2 / 2 ) v , where R 4 As described above, the subscript u is 0 or greater, the subscript v is 1 or greater, and the amount (u+v) is 3 to 15. Alternatively, u may be 0. Alternatively, u may be 0 or greater, alternatively 1 or greater, alternatively 2 or greater, alternatively 3 or greater; at the same time, u may be at most 6, alternatively at most 5, and alternatively at most 4. Alternatively, u may be 0 to 6, alternatively 0 to 4, alternatively 0 to 2, and alternatively 1 to 6. Alternatively, v may be 1 or greater, alternatively 2 or greater, alternatively 3 or greater, and alternatively 4 or greater; at the same time, v may be 12 or less, alternatively 10 or less, alternatively 8 or less, alternatively 6 or less, and alternatively 5 or less. Alternatively, the average value of v may be 4. Alternatively, v may be 1 to 12, alternatively 2 to 10, alternatively 3 to 8, alternatively 3 to 6, and alternatively 3 to 5. In unit formula (B-2), each R 4 Examples of the cyclic polyorganohydrogensiloxane include (i) trimethylcyclotrisiloxane, (ii) tetramethylcyclotetrasiloxane, (iii) pentamethylcyclopentasiloxane, (iv) hexamethylcyclohexasiloxane, and (v) a combination of two or more thereof.

[0032] Suitable polyorganohydrogensiloxanes are known in the art and are commercially available. For example, DOWSIL TM 6-3570 polymer, DOWSIL TM SH 1107 Fluid and XIAMETER TMMHX-1107 fluid is available from The Dow Chemical Company, Midland, Michigan, USA. Polydiorganohydrogensiloxanes such as HMS-992 (trimethylsilyl terminated polymethylhydrogensiloxane), HMS-HM271 (hydride terminated methylhydrogensiloxane-dimethylsiloxane copolymer), and HMS-031 (trimethylsiloxy terminated methylhydrogensiloxane dimethylsiloxane copolymer) are available from Gelest, Inc., Morrisville, Pennsylvania, USA. Other polydiorganohydrogensiloxanes available from Gallester include HMS-H271, HMS-071, HMS-993; HMS-301 and HMS-301R, HMS-991, HMS-993, HMS-082, HMS-151, HMS-013, HMS-053, HAM-301 (which is octyl functional) and HPM-502 (which is phenyl functional). Methods for preparing linear and branched polyorganohydrogensiloxanes suitable for use herein, such as hydrolysis and condensation of organohalosilanes, are well known in the art, as exemplified in U.S. Pat. Nos. 3,957,713 to Jeram et al.; 4,329,273 to Hardman et al.; 4,370,358 to Hayes et al.; 4,707,531 to Shirahata; 5,310,843 to Morita; and 2,823,218 to Speier et al., which disclose organohydrogensiloxane oligomers and linear polymers, as well as cyclic polymethylhydrogensiloxanes.

[0033] The exact amount of polyorganohydrogensiloxane in the composition depends on various factors, including the Si-H content of the polyorganohydrogensiloxane (which can be determined using quantitative infrared analysis according to ASTM E168), and the type and amount of (C) hydrocarbyloxy-functional organosilicon compound. However, the amount of (B) polyorganohydrogensiloxane in the composition may be 1 wt% or more, alternatively 5 wt% or more, alternatively 10 wt% or more, alternatively 15 wt% or more, alternatively 20 wt% or more, and alternatively 25 wt% or more, while the concentration may be <100 wt%, alternatively 90 wt% or less, alternatively 85 wt% or less, alternatively 80 wt% or less, alternatively 75 wt% or less, and alternatively 60 wt% or less; based on the combined weight of (A) catalyst, (B) polyorganohydrogensiloxane, and (C) hydrocarbyloxy-functional organosilicon compound in the composition. Alternatively, the amount of (B) polyorganohydrogensiloxane in the composition may be 1 wt% to <100 wt%, alternatively 5 wt% to 90 wt%, alternatively 10 wt% to 85 wt%, alternatively 15 wt% to 80 wt%, alternatively 20 wt% to 75 wt%, alternatively 25 wt% to 70 wt%, and alternatively 30 wt% to 90 wt%, each based on the combined weight of (A) catalyst, (B) polyorganohydrogensiloxane, and (C) hydrocarbyloxy-functional organosilicon compound in the composition.

[0034] The polyorganohydrogensiloxane (B) may be the same or different molecule from the (C-2) hydrocarbyl functional organosiloxane oligomer or polymer described below. That is, if the composition comprises an organosiloxane oligomer or polymer having both Si-H moieties and silicon-bonded hydrocarbyl functional moieties, the polymer or oligomer may also contain Si-H moieties and serve as both starting materials (B) and (C) in the composition. For example, when both Si-H moieties and hydrocarbyl moieties are present in the same molecule, R in the formula shown above is 4 One or more examples of may be replaced by a hydrocarbyl moiety of formula (c) shown below. Alternatively, the (B) polyorganohydrogensiloxane may be a different molecule from the (C) hydrocarbyl functional organosilicon compound also in the composition. The starting material (C) hydrocarbyl functional organosilicon compound may not contain Si-H moieties.

[0035] Starting material (C) Hydroxyl functional organosilicon compound

[0036] The starting material (C) hydrocarbyloxy-functional organosilicon compound in the composition has a formula selected from the group consisting of: (C-1) hydrocarbyloxysilane, (C-2) hydrocarbyloxy-functional organosiloxane oligomer or polymer, and (C-3) a combination of (C-1) and (C-2).

[0037] Hydrocarbyloxysilane has the formula (C-1): R 7(4-b) Si(OR 5 ) b , where each R 7 independently selected from the group consisting of a monovalent hydrocarbon group and a monovalent halogenated hydrocarbon group, each R 5 is a monovalent hydrocarbon group having 1 to 6 carbon atoms, and subscript b is 1 to 4. R 7 The monovalent hydrocarbon group and the monovalent halogenated hydrocarbon group are as described above for R 3 Description and examples. 5 The monovalent hydrocarbon group having 1 to 6 carbon atoms may be an alkyl group, such as methyl, ethyl, propyl (including isopropyl, n-propyl), butyl (including n-butyl, isobutyl, tert-butyl and sec-butyl), and pentyl, hexyl, branched chain isomers having 5 to 6 carbon atoms. Alternatively, each R 5 Alternatively, the subscript b may be 1 or more, alternatively 2 or more, while the subscript b may be 4 or less, alternatively 3 or less. Alternatively, the subscript b may be 1 to 3, alternatively 1 to 2, alternatively 2 to 3, and alternatively 2 to 4.

[0038] Alternatively, the hydrocarbyloxysilane may have the formula R 7 Si(OR 5 )3, where R 7 and R 5 As described above. Alternatively, each R 7 may be an alkyl group having 1 to 20 carbon atoms, and each R 5 It may be an alkyl group having 1 to 4 carbon atoms.

[0039] The starting material (C-1) hydrocarbyloxysilane may include alkoxysilanes, examples of which are: monoalkoxysilanes, such as trialkylalkoxysilanes; dialkoxysilanes, such as dialkyldialkoxysilanes; trialkoxysilanes, such as alkyltrialkoxysilanes; tetraalkoxysilanes; or combinations thereof. Examples of suitable monoalkoxysilanes include trimethylmethoxysilane, trimethylethoxysilane, triethylethoxysilane, triethylmethoxysilane, vinyldimethylethoxysilane, allyldimethylmethoxysilane, vinyldimethylmethoxysilane, dimethylphenylmethoxysilane, methyldiphenylmethoxysilane, triphenylmethoxysilane, and combinations thereof. Examples of suitable dialkoxysilanes include diisobutyldiethoxysilane, n-octadecylmethyldiethoxysilane, diphenyldiethoxysilane, diphenyldimethoxysilane, di(4-tolyl)dimethoxysilane, and combinations thereof. Examples of suitable trialkoxysilanes include methyltrimethoxysilane, methyltriethoxysilane, ethyltrimethoxysilane, ethyltriethoxysilane, isobutyltrimethoxysilane, isobutyltriethoxysilane, n-octyltrimethoxysilane, n-octyltriethoxysilane, allyltrimethoxysilane, vinyltrimethoxysilane, vinyltriethoxysilane, phenyltrimethoxysilane, p-tolyltrimethoxysilane, p-tolyltriethoxysilane, pentafluorophenyltriethoxysilane, 4-trifluoromethyltetrafluorophenyltriethoxysilane, 1-naphthyltriethoxysilane, 1-naphthyltrimethoxysilane, benzyltriethoxysilane, and combinations thereof. Examples of suitable tetraalkoxysilanes include tetraethoxysilane and tetra-n-propoxysilane. These alkoxysilanes are known in the art and can be prepared by known methods, such as alkoxylation of the corresponding chlorosilanes, and / or suitable alkoxysilanes are commercially available, for example, from Gelest, Inc. of Morrisville, Pennsylvania, USA.

[0040] Other commercially available alkoxysilanes include XIAMETER TM OFS-6070 Silane, XIAMETER TM OFS-6011 Silane, XIAMETER TM OFS-6020 Silane, XIAMETER TM OFS-6030 Silane, DOWSIL TM Z-6062 silane, DOWSIL TM Z-6300 silane, DOWSIL TM Z-6341 Silane, XIAMETER TM OFS-6040 Silane, DOWSIL TM Z-6023 silane, DOWSILTM Z-6015 silane, XIAMETER TM OFS-6920 Silane, XIAMETER TM OFS-6690 Silane and XIAMETER TM OFS-6076 Silane; all of these materials are commercially available from The Dow Chemical Company of Midland, Michigan, USA.

[0041] Alternatively, the (C) hydrocarbyloxy-functional organosilicon compound may include a (C-2) hydrocarbyloxy-functional organosiloxane oligomer or polymer comprising a silicon-bonded hydrocarbyloxy-functional moiety of formula (c):

[0042] wherein each D independently represents an oxygen atom, a divalent hydrocarbon group, a divalent siloxane group, or a combination of a divalent hydrocarbon group and a divalent siloxane group; each R X Independent expression – OR 5 A group in which each R 5 As mentioned above; each R 6 Independently selected from the above for R 3 The group consisting of the monovalent hydrocarbon group and the monovalent halogenated hydrocarbon group; the subscript c represents 0, 1, 2 or 3; the subscript e represents 0, 1 or 2; and the value of the subscript d is 0 or greater, provided that the sum of (e+c) is at least 1, so that on average there is at least one R in the formula X Alternatively, the value of subscript d may have a value from 0 to 18. Alternatively, subscript c may be 1. Alternatively, subscript c may be 2 or 3. Alternatively, subscript e may be 0. Alternatively, subscript d may be 0. Alternatively, subscript d may be 2 to 5, alternatively 2 to 3.

[0043] Alternatively, each D may be independently selected from an oxygen atom and a divalent hydrocarbon group. Alternatively, each D may be an oxygen atom. Alternatively, each D may be a divalent hydrocarbon group, exemplified by an alkylene group such as ethylene, propylene, butylene or hexylene; an arylene group such as phenylene, or an alkylene aryl group such as:

[0044]

[0045] Alternatively, one example of D may be an oxygen atom, while a different example of D is a divalent hydrocarbon group.

[0046] Alternatively, each R X may be independently selected from the group consisting of alkoxy groups and alkenyloxy groups. XIt may be an alkoxy group such as methoxy or ethoxy.

[0047] Alternatively, each R in the above formula 6 The alkyl radicals may be independently selected from an alkyl group having 1 to 20 carbon atoms, an aryl group having 6 to 20 carbon atoms, and an aralkyl group having 7 to 20 carbon atoms.

[0048] The organosiloxane oligomer or polymer may contain the hydrocarbyl functional moiety of the formula shown above in an amount of 0.2 mol% or more, alternatively 0.5 mol% or more, alternatively 0.6 mol% or more, while the amount may be 10 mol% or less, alternatively 5 mol% or less, alternatively 2 mol% or less, alternatively 1.5 mol% or less, and alternatively 1.2 mol% or less. Alternatively, the amount of the hydrocarbyl functional moiety of the formula shown above may be 0.2 mol% to 10 mol%, alternatively 0.5 mol% to 5 mol%, alternatively 0.5 mol% to 2.0 mol%, alternatively 0.5 mol% to 1.5 mol%, and alternatively 0.6 mol% to 1.2 mol%.

[0049] The starting material (C-2) may have a linear polyorganosiloxane backbone, i.e., a polydiorganosiloxane backbone. When the starting material (C-2) hydrocarbyloxy-functional organosiloxane oligomer or polymer has a polydiorganosiloxane backbone, the starting material (C-2) may include an alkoxy-terminated polydiorganosiloxane, an alkoxysilylhydrocarbylene-terminated polydiorganosiloxane, or a combination thereof.

[0050] Alternatively, the starting material (C-2) may comprise formula (C-3):

[0051] A polydiorganosiloxane, wherein R 6 , R X and subscripts c, d, and e are as described above, and the value of subscript f is 1 or greater. Alternatively, subscript f may have a value sufficient to provide the polydiorganosiloxane of formula (C-3) with a viscosity of at least 100 mPa·s at 25° C. and / or a DP of at least 87. DP may be measured by GPC using polystyrene standards for calibration. Alternatively, the value of subscript f may be at least 1, alternatively at least 2, alternatively at least 5, alternatively at least 10, alternatively at least 50; while the value of subscript f may be at most 200,000, alternatively at most 100,000, alternatively at most 50,000, alternatively at most 2,000, alternatively at most 1,000, alternatively at most 500, and alternatively at most 100. Alternatively, the value of subscript f may range from 1 to 200,000. Alternatively, in the above formula (C-3), each R 6may be selected from the group consisting of alkyl, alkenyl and aryl. 6 The alkyl group of R may be selected from the group consisting of methyl, ethyl and propyl. 6 The alkenyl group of may be selected from the group consisting of vinyl, allyl and hexenyl. 6 The aryl group of may be phenyl. Alternatively, in the above unit formula, each R X It may be a methoxy group or an ethoxy group. The organosiloxane oligomers and polymers of formula (C-3) may be prepared, for example, as described in U.S. Patent Application Publication No. 2020-0140618 or PCT Publication No. WO2019 / 005711 or WO2019 / 005713.

[0052] Alternatively, the organosiloxane oligomer or polymer may include units of formula (C-4): (R X R 6 2SiO 1 / 2 ) o (R 6 3SiO 1 / 2 ) p (R 6 2SiO 2 / 2 ) q (R X R 6 SiO 2 / 2 ) r (R X SiO 3 / 2 ) s (R 6 SiO 3 / 2 ) t (SiO 4 / 2 ) u , where R X Expression – OR 5 A group in which R 5 As described above, the values ​​of the subscripts o, p, q, and r are such that o≥0, p≥0, q≥0, r≥0, s≥0, t≥0, u≥0, the average value of the quantity (o+r+s) is 1 or greater, alternatively 1 to 6, alternatively 1 to 3, and alternatively 1 to 2; and each R 6 Independently selected from the above for R 3The monovalent hydrocarbon group and the monovalent halogenated hydrocarbon group are composed of the group. Alternatively, the amount (o+p+q+r+s+t+u) may be at least 3, alternatively 3 to 2000. Alternatively, the amount (q+r) may be 1 to 2,000, alternatively 1 to 50. Alternatively, the amount (o+p) may be 0 to 50, alternatively 0 to 2. Alternatively, 1≥s≥0. Alternatively, 1≥t≥0. Alternatively, the average value of the amount (o+r+s) may be 1 to 6, alternatively 1 to 3 and alternatively 1 to 2. Alternatively, in the above unit formula (C-4), each R 6 may be selected from the group consisting of alkyl, alkenyl and aryl. 6 The alkyl group of R may be selected from the group consisting of methyl, ethyl and propyl. 6 The alkenyl group of may be selected from the group consisting of vinyl, allyl and hexenyl. 6 The aryl group of may be phenyl. Alternatively, in the above unit formula, each R X It may be methoxy or ethoxy.

[0053] Alternatively, (for example, when o has an average value of 2 and p=r=s=t=u=0), the starting material (C-2) may comprise the formula (C-5): R 6 2R X SiO-(R 6 2SiO) b -OSiR X R 6 2 polydiorganosiloxane, wherein each R 6 and each R X As described above, and subscript b ≥ 1. Alternatively, subscript b may be 1 to 2,000, alternatively 5 to 900, alternatively 5 to 50, and alternatively subscript b may be 1 to 50. Alternatively, in formula (C-5), each R 6 may be independently selected from the group consisting of alkyl (e.g., methyl, ethyl, and propyl), alkenyl (e.g., vinyl, allyl, and hexenyl), and aryl (e.g., phenyl). Alternatively, in formula (C-5), each R X The polydiorganosiloxane of formula (C-5), such as methoxy-terminated polydimethylsiloxane having a viscosity of 5 to 12 cSt, is commercially available from Galester, and 1,3-diethoxy-1,1,3,3-tetramethyldisiloxane is commercially available from Millipore Sigma of St. Louis, Missouri, USA.

[0054] Alternatively, the starting material (C-2) may include a unit formula (C-6): (R 6 SiO3 / 2 ) m (R 6 R X SiO 2 / 2 ) n (R 6 2R X SiO 1 / 2 ) z , where R 6 and R X As described above, and subscript m is >0 to 100, subscript n is 0 to 100, and subscript z is 0 to 20. Alternatively, subscript m may be >0 to 20, alternatively 1 to 20. Alternatively, subscript n may be 1 to 20. Alternatively, subscript z may be 0. Alternatively, subscript z may be >0 to 20. Alternatively, in unit formula (C-6), each R 6 may be independently selected from the group consisting of an alkyl group (e.g., methyl, ethyl, and propyl), an alkenyl group (e.g., vinyl, allyl, and hexenyl), an aryl group (e.g., phenyl), and a halogenated alkyl group (e.g., chloromethyl, chloropropyl, and trifluoropropyl). Alternatively, in the unit formula (C-6), each R X It may be methoxy or ethoxy. Those skilled in the art will recognize that the alkoxy-functional siloxane resin may also include hydroxyl groups. Examples of suitable alkoxy-functional siloxane resins of formula (C-6) include DOWSIL 9000 from Dow Silicones Corporation of Midland, Michigan, USA. TM 3037、DOWSIL TM 3074、DOWSIL TM 1686、DOWSIL TM CF0189, DOWSIL TM Z-6289、DOWSIL TM US-CF2403Resin and DOWSIL TM 2405 Resin.

[0055] Suitable resins for starting material (C-2) and methods for their preparation are known in the art. For example, alkoxy-functional organopolysiloxane resins or resin-polymer blends prepared as described in U.S. Pat. No. 9,670,392, U.S. Pat. No. 10,125,225, or PCT Publication No. WO2014 / 124389 can be used as starting material (C-2) herein.

[0056] The starting material (C) may include one or more of the hydrocarbyl functional organosilicon compounds described herein. The exact amount of the (C) hydrocarbyl functional organosilicon compound in the composition depends on various factors, including the Si-H content of the polyorganosiloxane and the type and amount of the (C) hydrocarbyl functional organosilicon compound selected. However, based on the combined weight of the (A) catalyst, the (B) polyorganohydrogensiloxane and the (C) hydrocarbyl functional organosilicon compound in the composition, the amount of the (C) hydrocarbyl functional organosilicon compound in the composition may be 1 wt % or more, alternatively 2 wt % or more, alternatively 3 wt % or more, alternatively 4 wt % or more, and alternatively 5 wt % or more, while the concentration may be 90 wt % or less, alternatively 70 wt % or less, alternatively 50 wt % or less, alternatively 30 wt % or less, and alternatively 15 wt % or less. Alternatively, the amount of (C) the hydrocarbyloxy-functional organosilicon compound in the composition (when the starting materials (B) and (C) are different components) may be 1 wt % to 90 wt %, alternatively 2 wt % to 70 wt %, alternatively 3 wt % to 50 wt %, alternatively 4 wt % to 30 wt %, alternatively 5 wt % to 15 wt %, and alternatively 6 wt % to 14 wt %, each based on the combined weight of (A) catalyst, (B) polyorganohydrogensiloxane and (C) hydrocarbyloxy-functional organosilicon compound in the composition.

[0057] Starting material (D) Solvent

[0058] Starting material (D) is an optional solvent, which can be used to promote the combination of starting materials (A), (B) and / or (C) in the compositions and methods described herein. Solvents used herein are those that contribute to the fluidization of starting materials but do not react with any of these starting materials substantially. Solvents can be selected based on the solubility of starting materials and the volatility of solvents. Solubility refers to that the solvent is sufficient to dissolve and / or disperse the starting materials. Volatility refers to the vapor pressure of the solvent. For example, starting material (A) phosphonium catalyst can be dissolved in a solvent before mixing starting material (A) with starting material (B) and (C). Alternatively, starting material (B) can be dissolved in a solvent before mixing with starting material (A) and (C), for example, when starting material (B) is a viscous fluid, such as gum, or is solid at room temperature, such as resin. Alternatively, starting material (C) can be dissolved in a solvent before mixing with starting material (A) and (B), for example, when starting material (C) is solid at room temperature, such as resin or gum. The solvent may be used in any amount which will be selected by one skilled in the art based on factors such as its solubility in the selection of starting materials (A), (B) and (C).

[0059] Suitable solvents may be hydrocarbons. Suitable hydrocarbons include aromatic hydrocarbons such as benzene, toluene or xylene; and / or aliphatic hydrocarbons such as heptane, hexane or octane. Alternatively, the solvent may be a halogenated hydrocarbon such as chloroform, 1,1,1-trichloroethane or methylene chloride. One solvent or a combination comprising two or more solvents may be used herein.

[0060] The amount of solvent may depend on a variety of factors, including the type of solvent selected and the amount and type of other starting materials selected. However, the amount of solvent may be 0.1 wt % or more, alternatively 2 wt % or more, based on the combined weight of starting materials (A), (B) and (C), while the amount of solvent may be up to 99 wt %, alternatively up to 50 wt %. Alternatively, the amount of (D) solvent may be 0.1 wt % to 99 wt %, alternatively 2 wt % to 50 wt %, based on the combined weight of (A) catalyst, (B) polyorganohydrogensiloxane and (C) hydrocarbyloxy-functional organosilicon compound in the composition.

[0061] The composition may be composed of a phosphonium catalyst, a polyorganohydrogensiloxane, and a hydrocarbyloxy-functional organosilicon compound (and, when a solvent is present, a solvent). Alternatively, the composition described herein may optionally further comprise additional components. The optional additional components may be present in a concentration of 50 wt % or less, 40 wt % or less, 30 wt % or less, 20 wt % or less, 10 wt % or less, 5 wt % or less, or even 1 wt % or less, based on the weight of the composition.

[0062] Optional additional components

[0063] Examples of possible optional components include one or a combination of more than one component selected from the group consisting of: pigments, such as carbon black or titanium dioxide; fillers, such as metal oxides, including SiO2 (typically at a concentration of 50 wt% or less, based on the weight of the composition); moisture scavengers; fluorescent brighteners; stabilizers (such as antioxidants and UV stabilizers); and corrosion inhibitors.

[0064] Alternatively, in addition to or in place of the above optional components, the composition may further optionally include a polyorganosiloxane containing no Si-H moiety and no hydrocarbyloxy moiety. The polyorganosiloxane contains a polysiloxane selected from R 4 3SiO 1 / 2 , R 4 2SiO 2 / 2 , R 4 SiO 3 / 2 and SiO 4 / 2 two or more siloxane units of units; wherein each R 4is an independently selected monovalent hydrocarbon group free of aliphatic unsaturation, as described above. Alternatively, the polyorganosiloxane may be a polydiorganosiloxane, which may be linear or cyclic. For example, the polydiorganosiloxane may be a polydiorganosiloxane comprising the unit formula (1): (R 4 3SiO 1 / 2 )2(R 4 2SiO 2 / 2 ) x A linear polydiorganosiloxane, wherein R 4 As described above, and 1,000 ≥ x ≥ 1. Alternatively, the subscript x may be at least 1, alternatively at least 2, alternatively at least 3, alternatively at least 5, alternatively at least 10, alternatively at least 25; at the same time, the subscript x may be at most 1,000, alternatively at most 500, alternatively at most 250, alternatively at most 100, and alternatively at most 50. Alternatively, the value of the subscript x may be such that 500 ≥ x ≥ 1, alternatively 250 ≥ x ≥ 2, alternatively 100 ≥ x ≥ 5, alternatively 50 ≥ x ≥ 10, and alternatively 50 ≥ x ≥ 25.

[0065] Examples of linear polydiorganosiloxanes suitable for use herein are:

[0066] (i) α,ω-trimethylsiloxyl-terminated polydimethylsiloxane,

[0067] (ii) α,ω-dimethylphenylsiloxane-terminated poly(dimethylsiloxane / methylphenylsiloxane),

[0068] (iii) polymethylphenylsiloxane terminated with α,ω-dimethylphenylsiloxane,

[0069] (iv) α,ω-trimethylsiloxane-terminated poly(dimethylsiloxane / methylphenylsiloxane),

[0070] (v) α,ω-trimethylsiloxyl-terminated polymethylphenylsiloxane, and

[0071] (vi) a combination of two or more thereof.

[0072] Polydiorganosiloxanes are known in the art and are commercially available. For example, DOWSIL TM 200 fluid, DOWSIL TM OS Fluids and XIAMETER TM PMX-200 silicone fluid is commercially available from The Dow Chemical Company, Midland, Michigan, USA.

[0073] Alternatively, the polyorganosiloxane may be a polyorganosiloxane comprising unit formula (2): (R 4 2SiO 2 / 2 ) y Cyclic polydiorganosiloxane, wherein R 4 As described above, and 15≥y≥3. Alternatively, the subscript y may be at least 3, alternatively at least 4, alternatively at least 5, and alternatively at least 6; at the same time, the subscript y may be at most 15, alternatively at most 12, alternatively at most 10, alternatively at most 8, and alternatively at most 6. Alternatively, the value of the subscript y may be such that 12≥y≥3, alternatively 10≥y≥3, alternatively 8≥y≥3, alternatively 6≥y≥3, and alternatively 6≥y≥4.

[0074] Examples of cyclic polydiorganosiloxanes include hexamethylcyclotrisiloxane, octamethylcyclotetrasiloxane, decamethylcyclopentasiloxane, dodecamethylcyclohexasiloxane, and combinations of two or more thereof. These cyclic polydiorganosiloxanes are commercially available from Sigma-Aldrich, Inc., St. Louis, Missouri, USA.

[0075] The composition may alternatively be free of any one such additional component or any combination of more than one such additional components. In addition, the composition may comprise 1 wt % or less, alternatively 0.5 wt % or less water relative to the composition weight. Alternatively, the composition may be free of water.

[0076] The compositions described herein may be free of transition metals. "Free of transition metals" means that the composition does not contain metals in Groups 3-12 of the IUPAC Periodic Table of Elements as of December 1, 2018, or does not contain an undetectable amount, or an amount insufficient to form a gel of the composition after 24 hours at room temperature. Without wishing to be bound by theory, it is believed that transition metals may catalyze the reaction of starting materials (B) and (C) at undesirably low temperatures (e.g., <65° C.).

[0077] The composition described herein may be free of Lewis bases. "Free of Lewis bases" means that the composition does not contain a compound or ionic species or contains an insufficient amount of a compound or ionic species that can donate electron pairs to the (A) phosphonium catalyst to prevent the composition from being sufficiently cured to form a gel within 20 minutes when heated at 65°C. For example, the composition may be free of a Lewis base selected from the group consisting of: PR 10 3. P(NR 10 2)3、NR 10 3. N(SiR 10 3) x R 10 3-x , R 10C(NR 10 )N、P(NR 10 )R 10 3. Guanidine (C(=NR 10 )(NR 10 2)2)Amidine (R 10 C(=NR 10 )NR 10 2) Phosphazene and Where R 10 and R at each occurrence is independently selected from the group consisting of hydrogen, alkyl, substituted alkyl, aryl, and substituted aryl.

[0078] method

[0079] The above composition can be a one-component composition. The one-component composition contains starting materials (A), (B) and (C) in the same component. The composition can be prepared by a method comprising the following steps: i) mixing the above-mentioned starting materials comprising (A) phosphonium catalyst, (B) polyorganohydrogensiloxane and (C) alkoxy-functional organosilicon compound and (D) solvent and / or optional additional components (when present) to form a mixture. Starting material (D) solvent can be used to promote the mixing of starting materials (A), (B) and (C). For example, one or more of starting materials (A), (B) and (C) can be dissolved in a solvent before mixing with other starting materials. Alternatively, the starting material can be substantially composed of the above-mentioned starting materials (A), (B) and (C) (and optional (D)). Alternatively, the starting material can be composed of the above-mentioned starting materials (A), (B) and (C) (and optional (D)).

[0080] The starting materials are mixed to form a mixture and prepare the polyorganosiloxane composition in such a way that the silicon-bonded hydrogen atoms of the starting material (C) and the starting material (B) do not cure (e.g., do not significantly cure the organic phase of the formula OR 5 The radical reaction, where R 5As described above). These conditions may include, for example, mixing by any convenient means. Mixing may be performed using conventional mixing equipment, such as a batch stirred tank. Alternatively, when the alkoxy-functional organosilicon compound selected for the starting material (C) and / or the polyorganohydrogensiloxane selected for the starting material (B) is viscous or solid (e.g., gum or resin), mixing under shear may be performed, for example, using an extruder. The composition may be formed, for example, by mixing the starting materials comprising (A), (B) and (C) described above. The starting materials (A), (B) and (C) may be mixed at room temperature or lower. Alternatively, the temperature for mixing the starting materials (A), (B) and (C) (and (D), when present) may be 5°C to 30°C. The starting materials (A), (B) and (C) (and (D), when present) may be mixed simultaneously. Alternatively, starting materials (A) and (B) (and (D), when present) may be mixed to form a mixture, and thereafter, the mixture may be mixed with starting material (C) (and further (D), when present), for example by adding starting material (C) (or a solvent solution thereof) to the mixture, for example by metering over a period of time or by adding in one or more aliquots.

[0081] Curing composition

[0082] A method for curing a composition, the method comprising:

[0083] 1) providing the composition as described above, and

[0084] 2) heating the composition to a temperature sufficient to catalyze the reaction of silicon-bonded hydrogen atoms in (B) the polyorganohydrogensiloxane and silicon-bonded alkoxy groups in (C) the alkoxy-functional organosilicon compound. The resulting product prepared in step 2) includes the reaction product of the starting materials (B) and (C) (which has a siloxane bond) and includes HR 5 The by-products, R 5 As described above. For example, the heating temperature in step 2) may be ≥ 65°C. Alternatively, the temperature may be > 30°C, but the reaction time may be longer at lower temperatures than at higher temperatures.

[0085] The method for curing the composition may optionally further comprise one or more additional steps. For example, the reaction in step 2) produces the formula HR as described above. 5 The method may also include removing the byproduct of formula HR during and / or after step 2). 5 By-products. By-products HR 5The removal can be carried out in any convenient manner, such as stripping and / or placing the reaction product under reduced pressure / vacuum. For example, the method may further include an additional step after step 1) and before step 2), wherein the additional step includes placing the composition in a mold or applying the composition on a substrate.

[0086] Example

[0087] These examples are provided to illustrate the present invention to those skilled in the art and should not be construed as limiting the scope of the invention described in the claims. The starting materials used in these examples are shown in Table 1.

[0088] Table 1 - Starting Materials

[0089]

[0090]

[0091] Reference Example 1—General Conditions

[0092] Use in Reactions were performed in a N2-filled glove box with solvents dried over molecular sieves. Except as specified in Table 1, all starting materials were purchased from commercial sources and used as received.

[0093] Catalyst stock solutions were prepared as follows: [(C6F5)3PF][B(C6F5)4] (3.6 mg) was dissolved in CH2Cl2 (0.514 mL) to give [(C6F5)3PF][B(C6F5)4] stock solution A (7 mg / mL). 0.1 mL of [(C6F5)3PF][B(C6F5)4] stock solution A was added to a separate vial, followed by the addition of CH2Cl2 (1.0 mL) to give [(C6F5)3PF][B(C6F5)4] stock solution B (0.7 mg / mL).

[0094] [P(C6F5)3F][F] (6.6 mg) was dissolved in CH2Cl2 (0.94 mL) to give [P(C6F5)3F + [F] Stock solution A' (7 mg / mL). 0.1 mL of [P(C6F5)3F][F] stock solution A' was added to a separate vial, followed by CH2Cl2 (1.0 mL) to give [P(C6F5)3F][F] stock solution B' (0.7 mg / mL).

[0095] [(C6F5)3PF][B(C6F5)4]+NEt3 stock solution A: Et3N and catalyst 1 were added in a 1:1 molar ratio. Et3N stock solution (79.3 μL Et3N in 1 mL CH2Cl2) was added to the reaction mixture first, followed by catalyst stock solution B (0.7 mg / mL).

[0096] FAB (2.9 mg) was dissolved in CH2Cl2 (0.414 mL) to give FAB stock solution A" (7 mg / mL). 0.1 mL of FAB stock solution A" was added to a separate vial followed by CH2Cl2 (1.0 mL) to give FAB stock solution B" (0.7 mg / mL).

[0097] Reference Example 2 - Reaction Setup and Process of Working Example Using Catalyst 1 at Room Temperature

[0098] Add M to a 30 mL vial equipped with a magnetic stirrer. H D 16.55 M H (0.5 mL, 0.47 g, 0.34 mmol), n-octyl Si(OMe)3 (58.8 μL, 0.054 g, 0.23 mmol), and then 67.2 μL of [(C6F5)3PF][B(C6F5)4] stock solution B (0.047 mg, based on M H D 16.55 M H The reaction mixture was stirred overnight at room temperature. The reaction mixture turned into a gel, or no change was observed. Gel formation indicates curing (crosslinking), while no change in viscosity indicates no reaction. The results are shown in Table 2 below.

[0099] Reference Example 3 - Reaction Setup and Process of Comparative Example

[0100] Reference Example 2 was repeated except that 67.2 μL of FAB stock solution B (0.047 mg of FAB, based on M H D 16.55 M H The results are shown in Table 2 below.

[0101] Reference Example 4

[0102] Reference Example 2 was repeated except that 67.2 μL of [P(C6F5)3F][F] stock solution B (0.047 mg of [P(C6F5)3F][F], based on M H D 16.55 M H The results are shown in Table 2 below.

[0103] Reference Example 5

[0104] Reference Example 2 was repeated except that 67.2 μL of [P(C6F5)3F][F] stock solution B (0.047 mg of [P(C6F5)3F][F], based on M H D 16.55 M H =100 ppm) + 67.2 μL of NEt3 stock solution B (1:1 molar ratio with catalyst 1). The results are shown in Table 2 below.

[0105] Reference Example 6 - Reaction Setup and Process for Working Example Using Catalyst 1 at 65°C

[0106] Add M to a 30 mL vial equipped with a magnetic stirrer. H D 16.55 M H (0.5 mL, 0.47 g, 0.34 mmol), n-octyl Si(OMe)3 (58.8 μL, 0.054 g, 0.23 mmol), and then 67.2 μL of [(C6F5)3PF][B(C6F5)4] stock solution B (0.047 mg, based on M H D 16.55 M H The reaction mixture was stirred at 65°C over a preheated aluminum block. The reaction mixture turned into a gel, or no change was observed. Gel formation indicates curing (crosslinking), while no change in viscosity indicates no reaction. The results are shown in Table 2 below.

[0107] Reference Example 7 - Reaction Setup and Process of Comparative Example

[0108] Reference Example 6 was repeated except that 67.2 μL of [(C6F5)3PF][B(C6F5)4] (0.047 mg of [(C6F5)3PF][B(C6F5)4] + 67.2 μL of NEt3 stock solution B (1:1 molar ratio with catalyst 1) was used. The results are shown in Table 2 below.

[0109] Reference Example 8

[0110] Reference Example 6 was repeated except that 67.2 μL of [(C6F5)3PF][F] stock solution A (0.047 mg of [(C6F5)3PF][F]) was used. The results are shown in Table 2 below.

[0111] Table 2—Octyl Si(OCH3)3 and M H D 16.55 M H Using FAB (comparative), Catalyst 1 (invention) and Catalyst 2 Curing of (Comparative) .

[0112]

[0113]

[0114] The data in Table 2 of Reference Examples 2 and 6 show that phosphonium catalysts comprising a tetravalent monocation of phosphorus and a non-coordinating anion can be used to prepare a one-component composition that is stable (not gelled) for 7 days at room temperature but cures within 15 minutes at an elevated temperature of 65°C. Reference Examples 5 and 7 show that the presence of a Lewis base (triethylamine) prevents cure under the conditions tested. Reference Example 8 (last row of Table 2) shows that Catalyst 2, which comprises a strongly coordinating anion, did not cure the composition when tested at 65°C. Reference Example 3 shows rapid cure at room temperature when FAB is used instead of the catalyst described herein.

[0115] Industrial Applicability

[0116] The above-mentioned composition is shelf stable, which means that the composition will not gel at room temperature within 5 hours or less, alternatively within 24 hours or less, alternatively within 48 hours or less, and alternatively within a week or less. The compositions and methods described herein can be used to prepare and cure polyorganosiloxane compositions, which are cured to form products such as coatings, adhesives, elastomers and foams. The inventors were surprised to find that the catalysts described herein will cure the polyorganosiloxane compositions. In addition, the inventors were surprised to find that no Lewis base and / or bridging molecules are required to stabilize the catalysts described herein. In contrast, the presence of a Lewis base such as triethylamine can make the composition of the present invention uncurable under the conditions tested in the above examples. The compositions and methods of the present invention provide a polyorganosiloxane composition that is shelf stable at room temperature and can be cured when heated to a mild temperature.

[0117] Definition and usage of terms

[0118] Abbreviations used in the specification have the definitions in Table 3 below.

[0119] Table 3 - Abbreviations

[0120] abbreviation definition ASTM ASTM International ℃ Celsius d sky g gram GPC Gel Permeation Chromatography h Hour Me methyl mg mg min minute mL ml mmol mmol Ph Phenyl ppm Per million RT or rt Room temperature 23℃±2℃ s Second uL or μL microliter wt weight

[0121] Unless otherwise indicated, all amounts, ratios and percentages are by weight. The amount of all starting materials in the composition is 100% by weight. The Summary of the Invention and the Abstract are hereby incorporated by reference. Unless otherwise indicated in the context of this specification, the articles "a", "a kind" and "the" each refer to one (a kind) or more (a variety). Unless otherwise indicated, the singular includes the plural meaning.

[0122] The term "comprising" and its derivatives, such as "having" and "containing", are used in the broadest sense herein, meaning and encompassing the concepts of "including", "consisting essentially of", and "consisting of". The use of "for example", "for example", "such as", and "including" to list illustrative examples is not meant to be limited to the listed examples. Thus, "for example" or "such as" means "for example, but not limited to" or "such as, but not limited to" and encompasses other similar or equivalent examples.

[0123] Generally, as used herein, a hyphen “-” or dash “–” within a range of values ​​means “to” or “up to”; ">” means “higher than” or “greater than”; “≥” means “at least” or “greater than or equal to”; “<” means “lower than” or “less than”; and “≤” means “at most” or “less than or equal to”.

[0124] Embodiments of the present invention

[0125] In a first embodiment, the composition comprises a mixture of:

[0126] 1 ppm to 1,000 ppm, based on the combined weight of the starting materials (A), (B), and (C), of (A) a phosphonium catalyst comprising:

[0127] (i) Formula [PR 1 3R 2 ] + A tetravalent monocation of phosphorus, wherein each R 1 Yes

[0128] An independently selected halogenated aryl group, wherein each R 8 is selected from Cl, F or -CF3, and each R 2 independently selected from Br, Cl, F and -CF3, and

[0129] (ii) Formula [BR 3 4] - of a non-coordinating anion, where each R 3 independently selected from the group consisting of a monovalent hydrocarbon group and a monovalent halogenated hydrocarbon group;

[0130] 1 wt % to <100 wt % of (B) a polydiorganohydrogensiloxane selected from the group consisting of:

[0131] Including unit type (B-1):

[0132] (HR 4 2SiO 1 / 2 ) g (R4 3SiO 1 / 2 ) h (R 4 2SiO 2 / 2 ) i (HR 4 SiO 2 / 2 ) j A linear polydiorganohydrogensiloxane, wherein each R 4 is an independently selected monovalent hydrocarbon group free of aliphatic unsaturation, and the values ​​of the subscripts g, h, i and j are such that g ≥ 0, h ≥ 0, the amount (g + h) = 2, i ≥ 0, j ≥ 0 and the amount (g + j) ≥ 1, and the amount (i + j) is 0 to 2,000;

[0133] Including unit formula (B-2): (R 4 2SiO 2 / 2 ) u (R 4 HSiO 2 / 2 ) v Cyclic polydiorganohydrogensiloxane, wherein R 4 As described above, subscript u is 0 or greater, subscript v is 1 or greater, and the amount (u+v) is 3 to 15; and

[0134] (B-3) A combination of (B-1) and (B-2); and

[0135] Based on the combined weight of the starting materials (A), (B) and (C), 1 to 90 wt% of the formula (C-1): R 7 (4-b) Si(OR 5 ) b (C) alkoxysilane, wherein each R 7 independently selected from the group consisting of a monovalent hydrocarbon group and a monovalent halogenated hydrocarbon group, each R 5 is a monovalent hydrocarbon group having 1 to 6 carbon atoms, and subscript b is 1 to 4; wherein the composition does not contain a Lewis base.

[0136] In a second embodiment, according to the composition of the first embodiment, (A) the phosphonium catalyst has the formula [(C6F5)3PF] + [B(C6F5)4] - .

[0137] In a third embodiment, according to the method of the first embodiment or the second embodiment, (B) the polyorganohydrogensiloxane is selected from the group consisting of:

[0138] (i) α,ω-dimethylhydrogensiloxy-terminated poly(dimethylsiloxane / methylhydrogensiloxane),

[0139] (ii) α,ω-dimethylhydrogensiloxy-terminated polymethylhydrogensiloxane,

[0140] (iii) α,ω-trimethylsilyloxy-terminated poly(dimethylsiloxane / methylhydrogensiloxane),

[0141] (iv) α,ω-trimethylsilyloxy-terminated polymethylhydrogensiloxane, and

[0142] (v) poly(dimethylsiloxane / methylhydrogensiloxane) terminated with α-dimethylhydrogensiloxy-ω-trimethylsiloxy,

[0143] (vi) polymethylhydrogensiloxane terminated with α-dimethylhydrogensiloxy-ω-trimethylsiloxy,

[0144] (vii) a combination of two or more thereof.

[0145] In a fourth embodiment, according to the composition of any one of the first to third embodiments, (C) the hydrocarbyloxysilane is selected from the group consisting of trimethylmethoxysilane, trimethylethoxysilane, triethylethoxysilane, triethylmethoxysilane, vinyldimethylethoxysilane, allyldimethylmethoxysilane, vinyldimethylmethoxysilane, dimethylphenylmethoxysilane, methyldiphenylmethoxysilane, triphenylmethoxysilane, diisobutyldiethoxysilane, n-octadecylmethyldiethoxysilane, diphenyldiethoxysilane, diphenyldimethoxysilane, di(4-tolyl)dimethoxysilane, methyltrimethoxysilane, triethoxysilane, 4-trifluoromethyltetrafluorophenyltriethoxysilane, 1-naphthyltriethoxysilane, 1-naphthyltrimethoxysilane, benzyltriethoxysilane, tetraethoxysilane and tetra-n-propoxysilane, and combinations of two or more thereof.

[0146] In a fifth embodiment, the composition according to any one of the first to fourth embodiments further comprises 1 to 99 weight percent of (D) a solvent, based on the total weight of the composition.

[0147] In a sixth embodiment, the composition of any one of the first to fifth embodiments is used to prepare a product selected from the group consisting of coatings, adhesives, elastomers, and foams.

[0148] In a seventh embodiment, wherein the composition of any one of the first to fifth embodiments is a curing system, and the method comprises i) adding the composition to a polyorganosiloxane formulation and ii) curing the polyorganosiloxane formulation to form a product selected from the group consisting of a coating, an adhesive, an elastomer, and a foam.

Claims

1. A composition comprising a mixture of: (A) a phosphonium catalyst comprising (i) a tetravalent monocation of phosphorus and (ii) a non-coordinating anion; (B) a polyorganohydrogensiloxane; and (C) a hydrocarbyloxy-functional organosilicon compound; wherein the composition does not contain a Lewis base.

2. The composition of claim 1, wherein (a) the tetravalent monocation of phosphorus is of the formula [PR 1 3R 2 ] + A Lewis acidic phosphonium cation, where each R 2 Independently selected from X', -CX'3 and -OR 9 The group consisting of, wherein each X' is independently selected from the group consisting of Br, Cl and F, and R 9 is an alkyl group or an aryl group; and each R 1 is an independently selected halogenated aryl group.

3. The composition according to claim 2, wherein each R 1 With the formula: Each R 8 independently selected from H, X and a group of formula -CX3, wherein each X is a halogen independently selected from Br, Cl or F; provided that at least one R 8 Not H.

4. The composition according to claim 3, wherein each R 8 independently selected from the group consisting of H, Cl, F and a group of formula -CF3, 5. A composition according to any one of claims 2 to 4, wherein (i) the tetravalent monocation of phosphorus has the formula 6. The composition according to any one of claims 2 to 5, wherein (b) the anion has the formula [BR 3 4] - , where each R 3 Independently selected from the group consisting of a monovalent hydrocarbon group and a monovalent halogenated hydrocarbon group.

7. The composition of claim 6, wherein (b) the anion has the formula B(C6F5)4 - .

8. The composition according to any one of claims 1 to 7, wherein (B) the polyorganohydrogensiloxane comprises a 4 2SiO 1 / 2 , R 4 3SiO 1 / 2 , HR 4 SiO 2 / 2 , R 4 2SiO 2 / 2 , R 4 SiO 3 / 2 ,HSiO 3 / 2 and SiO 4 / 2 two or more siloxane units of units; wherein each R 4 are independently selected monovalent hydrocarbon groups free of aliphatic unsaturation.

9. The composition according to claim 8, wherein (B) the polyorganohydrogensiloxane is selected from the group consisting of: (B-1) including unit type (HR 4 2SiO 1 / 2 ) g (R 4 3SiO 1 / 2 ) h (R 4 2SiO 2 / 2 ) i (HR 4 SiO 2 / 2 ) j A linear polyorganohydrogensiloxane, wherein R 4 as described above, and the values ​​of the subscripts g, h, i, and j are such that g≥0, h≥0, the amount (g+h)=2, i≥0, j≥0 and the amount (g+j)≥1, and the amount (i+j) is from 0 to 1,000; (B-2) includes unit formula (R 4 2SiO 2 / 2 ) u (R 4 HSiO 2 / 2 ) v Cyclic polyorganohydrogensiloxane, wherein R 4 As described above, subscript u is 0 or greater, subscript v is 1 or greater, the amount (u+v) is 3 to 15, and each R 4 are independently selected monovalent hydrocarbon groups; and (B-3) A combination of (B-1) and (B-2).

10. The composition according to any one of claims 1 to 9, wherein (C) the hydrocarbyloxy-functional organosilicon compound has an average of at least one moiety of the formula -OR 5 A silicon-bonded group wherein each R 5 is an independently selected monovalent hydrocarbon group having 1 to 6 carbon atoms.

11. The composition of claim 10, wherein (C) the hydrocarbyloxy-functional organosilicon compound has a formula selected from the group consisting of: Formula (C-1): R 7 (4-b) Si(OR 5 ) b A hydrocarbyloxysilane, wherein each R 7 independently selected from the group consisting of a monovalent hydrocarbon group and a monovalent halogenated hydrocarbon group, each R 5 is the monovalent hydrocarbon group having 1 to 6 carbon atoms as described above, and subscript b is 1 to 4; (C-2) a hydrocarbyloxy-functional organosiloxane oligomer or polymer, the hydrocarbyloxy-functional organosiloxane oligomer or polymer comprising the formula: wherein each D independently represents an oxygen atom, a divalent hydrocarbon group, a divalent siloxane group, or a combination of a divalent hydrocarbon group and a divalent siloxane group; each R X independently represents the formula -OR 5 A group in which each R 5 As mentioned above; each R 6 Independently selected from the above for R 5 The group consisting of the monovalent hydrocarbon group and the monovalent halogenated hydrocarbon group; the subscript c represents 0, 1, 2 or 3; subscript e represents 0, 1 or 2; and the value of subscript d is 0 or greater, provided that the sum of (e+c) is at least 1, so that on average there is at least one R in the formula X ;and (C-3) A combination of (C-1) and (C-2).

12. The composition according to claim 11, wherein (C-1) the hydrocarbyloxysilane is present and has the formula: R 7 S O 5 3, where R 7 is an alkyl group having 1 to 20 carbon atoms, and each R 5 is an alkyl group having 1 to 4 carbon atoms. 13 . The composition according to claim 1 , further comprising (D) a solvent.

14. The composition of any one of claims 1 to 13, wherein the composition is free of transition metals.

15. A method comprising the steps of: 1) Providing a composition according to any one of claims 1 to 14, and 2) heating the composition to a temperature sufficient to catalyze the reaction of (B) silicon-bonded hydrogen atoms of the polyorganohydrogensiloxane and (C) silicon-bonded hydrocarbyl groups of the hydrocarbyl-functional organosilicon compound; and Optionally, the method further comprises an additional step after step 1) and before step 2), wherein the additional step further comprises placing the composition in a mold, or applying the composition on a substrate.

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