Synthesis and use of urethane-functionalized alkoxysilalkylene silane compounds

Abstract

A urethane functionalized alkoxysilylalkylene silane compound and methods of making and using the same are provided. The compounds have the formula (R12) N-C (= O) O-Si (R22)-D-Si (OR4) 3, wherein R1 may be hydrogen, methyl or ethyl; in some embodiments, R1 may be methyl, R2 may be methyl, R4 may be methyl, and each example of D is a linear or branched alkylene group, such as-CH2-CH2-and-CH (CH3)-. The compound may be used to terminate a silanol moiety in a silanol functionalized polyorganosiloxane to produce a polyalkoxy functionalized polyorganosiloxane. The polyalkoxy functionalized polyorganosiloxanes are useful as cross-linkers in moisture curable room temperature vulcanized (RTV) silicone compositions.

Description

[0001] CROSS-REFERENCE TO RELATED APPLICATIONS

[0002] This application claims the benefit under 35 U.S.C. §119(e) of U.S. Provisional Patent Application Serial No. 63 / 392,299, filed on July 26, 2022. U.S. Provisional Patent Application Serial No. 63 / 392,299 is hereby incorporated by reference. Technical Field

[0003] A carbamate-functionalized alkoxysilanesilane compound and a method for preparing and using the same are provided. The compound can react with a polyorganosiloxane having a silanol moiety to form a polyalkoxy-functionalized polyorganosiloxane that can be used in a condensation-curable composition.

[0004] introduction

[0005] Polyalkoxy-functionalized polydiorganosiloxanes can be used for moisture-curable polyorganosiloxane compositions. Polyalkoxy-functionalized polyorganosiloxanes can be synthesized by terminating vinyl-functionalized polyorganosiloxanes with polyalkoxy-functionalized hydrogensiloxane oligomers via hydrosilylation reactions, as described in, for example, U.S. Patents 10968317, 11098163, 11168181, and 11161939 or PCT Patent Application Publication WO2020-0231755. However, the disadvantage of this end-capping method is that the cost is relatively high, and the number of commercially available vinyl-functionalized polyorganosiloxanes is relatively small, resulting in limited selection of expensive polyalkoxy-functionalized polyorganosiloxane products. Summary of the invention

[0006] A carbamate-functional alkoxysilanedisilane compound is provided.

[0007] Also provided are methods for preparing and using the compound. The compound can be used in a silanization reaction to end-cap the silanol moiety of a polyorganosiloxane. The resulting polyalkoxy-functional polyorganosiloxane can be used in a condensation-curable polyorganosiloxane composition. DETAILED DESCRIPTION

[0008] The compounds described above may include the following formula:

[0009] in

[0010] Each R 1 are independently selected from the group consisting of a hydrogen atom and an alkyl group having 1 to 6 carbon atoms, provided that R 1 Two instances of may be joined together to form a ring-like portion;

[0011] Each R 2 independently selected from the group consisting of alkyl and aryl;

[0012] D is alkylene; and

[0013] Each R 4 is an independently selected alkyl group having 1 to 6 carbon atoms.

[0014] In the formula of this compound, each R 1 Can be the same or different. 1 The alkyl group has 1 to 6 carbon atoms, and examples thereof are methyl, ethyl, propyl (including n-propyl and isopropyl), butyl (including n-butyl, tert-butyl, sec-butyl and isobutyl), pentyl (including n-pentyl and a branched saturated hydrocarbon group having 5 carbon atoms), and hexyl (including n-hexyl and a branched saturated hydrocarbon group having 6 carbon atoms). Alternatively, R 1 Two instances of may be bonded together to form a cyclic secondary amine moiety with the nitrogen atom shown in the formula of the compound. 1 may be independently selected from the group consisting of hydrogen and an alkyl group having 1 to 4 carbon atoms. 1 It may be selected from the group consisting of hydrogen, methyl and ethyl.

[0015] In the formula of this compound, each R 2 Can be the same or different. Each R 2 R is independently selected from the group consisting of alkyl and aryl. The alkyl group may have 1 to 6 carbon atoms and is as described above for R 1 For R 2 The aryl group of may have 6 to 12 carbon atoms, and examples thereof are phenyl, tolyl, xylyl, and naphthyl; alternatively phenyl. Alternatively, each R 2 It may be an alkyl group having 1 to 6 carbon atoms. 2 It can be methyl or ethyl. Alternatively, each R 2 It may be methyl.

[0016] In the formula of this compound, D is an alkylene group, which may have 2 to 20 carbon atoms, alternatively 2 to 10 carbon atoms, alternatively 2 to 8 carbon atoms, alternatively 2 to 6 carbon atoms, and alternatively 2 to 4 carbon atoms. Examples include {also shown as: -CH2-CH2-}, {also shown as: -CH(CH3)-}, {also shown as: -CH2-CH2-CH2-}, {Also shown as: -CH(CH3)-CH2-}, -CH2-CH2-CH2-CH2-, -CH2-CH(CH3)-CH2-, and -CH(CH3)-CH2-CH2-. Alternatively, each D may be selected from the group consisting of -CH2-CH2- and -CH(CH3)-.

[0017] In the formula of this compound, each R 4 Can be the same or different. Each R 4 is an independently selected alkyl group. The alkyl group may have 1 to 6 carbon atoms and is as described above for R 2 Alternatively, each R 4 It may be an alkyl group having 1 to 4 carbon atoms. 4 It can be methyl or ethyl. Alternatively, each R 4 It may be methyl.

[0018] Method for producing the compound

[0019] The above compound can be prepared by a method comprising the following steps:

[0020] 1) Combining starting materials comprising the following under conditions for achieving a reaction:

[0021] C) carbamate;

[0022] D) ClSiR 2 2H hydrochlorosilane, where R 2 as described above; and

[0023] Optional H) solvent;

[0024] Thereby forming a reaction product comprising:

[0025] E) Formula R 1 2NC(=O)O-SiR 2 2H carbamate-functionalized hydrosilane, where R 1 and R 2 as described above; and

[0026] J) by-products; and

[0027] 2) combining starting materials comprising the following under conditions for achieving a hydrosilylation reaction:

[0028] E) carbamate-functional hydridosilane;

[0029] F) Formula R 3 Si(OR 4 )3 alkenyl-functionalized alkoxysilane, wherein R 3is alkenyl, and

[0030] R 4 As mentioned above;

[0031] G) a hydrosilylation reaction catalyst;

[0032] Optional H) solvent;

[0033] Thereby forming a reaction product comprising:

[0034] I) The above-mentioned carbamate-functional alkoxysilanesilane compounds.

[0035] Starting material C), i.e., the carbamate used in step 1) of the above method, can be commercially available. For example, ammonium carbamate of formula H2N-C(=O)OH·NH3 can be purchased from Sigma Aldrich Inc. of St. Louis, Missouri, USA.

[0036] Alternatively, the process for preparing the compound may include an optional step of forming a carbamate. In an optional additional step, starting material A) may be used: having a 1 2NH, R 1 NH2 or a combination thereof consisting of an amine of the formula (wherein R 1 As described above). Suitable amines are known in the art and are commercially available. For example, the amine can be a dialkylamine, such as diethylamine (HN(CH2CH3)2) or dimethylamine (HN(CH3)2). Dialkylamines are commercially available from various sources, such as Sigma-Aldrich, St. Louis, Missouri, USA. Alternatively, the amine can be a monoalkylamine, such as propylamine (H2NCH2CH2CH3) or butylamine (H2NCH2CH2CH2CH3). Alternatively, the amine can be a cyclic secondary amine. Alternatively, a combination of dialkylamines and monoalkylamines can be used.

[0037] Starting material B) is carbon dioxide of the formula CO2, which is known in the art and is commercially available. For example, gaseous CO2 can be purchased from various sources, such as Air Products and Chemicals of Allentown, Pennsylvania, USA. Solid CO2 (dry ice) can also be purchased from various sources, such as EZPro Delivery.

[0038] Starting material (H) is a solvent that can be optionally used in the method. Solvents that can be used herein are solvents that help fluidize the starting material but do not substantially react with the starting material. The solvent can be selected based on the solubility of the starting material and the volatility of the solvent. Solubility refers to the solvent being sufficient to dissolve and / or disperse the starting material. Volatility refers to the vapor pressure of the solvent. Solvents used to prepare carbamates can include aromatic hydrocarbons, such as benzene, toluene, ethylbenzene, or xylene; aliphatic hydrocarbons, such as heptane, hexane, or octane; halogenated hydrocarbons, such as dichloromethane or chloroform; or a combination of two or more thereof. Such solvents are known in the art and are commercially available.

[0039] The above optional step for forming the carbamate can be carried out by any convenient means, such as adding the amine and solvent (if present) to a reaction vessel and bubbling gaseous CO2 through the vessel, or by adding dry ice to the reaction vessel containing the amine and solvent (if present). During the formation of the carbamate, the headspace in the reaction vessel can be maintained under inert conditions, such as with an inert gas (e.g., nitrogen). The carbamate formed can have the formula R 1 2NH2 + R 1 2NC(=O)O - , where R 1 As described above. In this process, the formation of the carbamate according to an optional step may be carried out before step 1). The amount of B) carbon dioxide is not critical but may be in molar excess relative to A) amine.

[0040] In step 1) of the method, C) the above carbamate and D) a compound of the formula ClSiR 2 2H hydrochlorosilane (where R 2 As described above) starting materials are combined under conditions to achieve a reaction of carbamate and chlorine. Hydrochlorosilanes are known in the art and can be prepared by known methods such as the Direct Process. Examples of hydrochlorosilanes include dimethylchlorosilane (Me2HSiCl) and phenylmethylchlorosilane (PhMeHSiCl), which are commercially available from Sigma-Aldrich.

[0041] Additional solvent may be added in step 1). The solvent in step 1) may be the same as or different from the solvent used to form the carbamate (if used). The hydrochlorosilane and solvent may optionally be combined, such as by mixing, before adding the hydrochlorosilane to the carbamate in the reaction vessel described above. Step 1) produces a reaction product including a carbamate-functional hydrosilane and byproducts. The carbamate-functional hydrosilane may have the formula R 1 2NC(=O)O-SiR 2 2H, where R1 and R 2 As mentioned above.

[0042] Step 1) can be carried out by mixing starting materials including C) carbamate and D) hydrochlorosilane (and H) solvent (if present). Mixing can be carried out at RT, alternatively heated to a temperature that does not decompose the carbamate, for example ≤150°C. Alternatively, step 1) can be carried out under cooling. Step 1) can be carried out under inert dry conditions. Step 1) produces a reaction product including E) carbamate-functional hydrosilane and by-products. . The method can optionally further include purifying the reaction product by any convenient means such as filtration, distillation and / or stripping to recover E) carbamate-functional hydrosilane and remove all or a portion of H) solvent (if used) and / or any by-products that may be formed, such as formula R 1 4N + Cl - Alkyl ammonium chloride, where R 1 As mentioned above.

[0043] The carbamate-functional hydridosilanes E) prepared as described above may have the formula R 1 2NC(=O)O-SiR 2 2H, where R 1 and R 2 As described above. In step 2) of the above method, a carbamate-functionalized hydrosilane is used, which step comprises combining starting materials comprising: E) a carbamate-functionalized hydrosilane, F) an alkenyl-functionalized alkoxysilane, G) a hydrosilylation catalyst, and optionally H) a solvent under conditions for achieving a hydrosilylation reaction.

[0044] The starting material F) may have the formula R 3 Si(OR 4 )3 alkenyl-functionalized alkoxysilane, wherein R 3 is alkenyl, and R 4 As described above. Alkenyl functionalized alkoxysilanes are known in the art and are commercially available. Examples include vinyl trimethoxysilane, vinyl triethoxysilane, allyl trimethoxysilane, allyl triethoxysilane, hexenyl trimethoxysilane, and hexenyl triethoxysilane, all of which are commercially available, for example, from Gelest, Inc. of Morrisville, Pennsylvania, USA.

[0045] In the above method, the amounts of the starting materials E) and F) are not critical, however, the starting materials E) and F) may be used in a weight ratio E) / F) of 1 / 1 to 1 / 5, or 1 / 1 to 1 / 3.

[0046] The starting material G) is a hydrosilylation catalyst. The catalyst will promote the reaction between the alkenyl group in F) the alkenyl functionalized alkoxysilane and the silicon-bonded hydrogen atoms in E) the carbamate functionalized hydrosilane. The catalyst comprises a platinum group metal. The platinum group metal may be selected from the group consisting of platinum, rhodium, ruthenium, palladium, osmium and iridium. Alternatively, the platinum group metal may be platinum. The hydrosilylation catalyst may be a platinum group metal or a compound or complex of a platinum group metal. For example, the hydrosilylation catalyst may be a compound such as chlorotris(triphenylphosphine)rhodium(I) (Wilkinson's Catalyst), a rhodium diphosphide chelate such as [1,2-bis(diphenylphosphino)ethane]dichlororhodium or [1,2-bis(diethylphosphino)ethane]dichlororhodium, chloroplatinic acid (Speier's Catalyst), chloroplatinic acid hexahydrate, platinum dichloride, or a complex of such a compound with an organopolysiloxane, such as a complex of 1,3-divinyl-1,1,3,3-tetramethyldisiloxane with platinum (Karstedt's Catalyst) or a Pt(0) complex in tetramethyltetravinylcyclotetrasiloxane (Ashby's Catalyst). Alternatively, the compound or complex may be microencapsulated in a matrix or core-shell structure. Hydrosilylation catalysts are known in the art, for example, as described in PCT Patent Application Publication No. WO2021 / 081822 and references cited therein. Hydrosilylation catalysts are commercially available, for example, SYL-OFF TM 4000 Catalyst and SYL-OFF TM 2700 is available from Dow Silicones Corporation, Midland, Michigan, USA.

[0047] The amount of G) hydrosilylation reaction catalyst is sufficient to catalyze the hydrosilylation reaction of the silyl hydride moiety of the starting material E) and the alkenyl group of the starting material F), and the amount depends on various factors, including the reaction conditions and the types of starting materials E) and F) selected, but the amount may be sufficient to provide a platinum group metal in an amount of at least 5 ppm, alternatively at least 50 ppm, alternatively at least 100 ppm, alternatively at least 200 ppm, and alternatively at least 400 ppm based on the combined weight of the starting materials E) and F); while at the same time, on the same basis, the amount of G) hydrosilylation reaction catalyst may be at most 10,000 ppm, alternatively at most 5,000 ppm, alternatively at most 2,000 ppm, alternatively at most 1,000 ppm, alternatively at most 600 ppm.

[0048] The starting material H) is a solvent as described above, which may be the same as or different from the solvent used in step 1) and / or in the optional step of forming the carbamate. The one or more starting materials used in step 2) described above may be dissolved or dispersed in a solvent before being combined in step 2). For example, the hydrosilylation reaction catalyst may be dissolved in a hydrocarbon solvent such as toluene before being used in step 2). The amount of solvent used in step 2) is not critical and may be, for example, 0% to 95% by weight, alternatively >0% to 90% by weight, based on the combined weight of the starting materials E), F), G) and H).

[0049] Step 2) can be carried out by any convenient means (such as mixing and heating). The same reaction vessel as step 1) can be used. Alternatively, a different reaction vessel can be used. The container can be purged with an inert gas such as nitrogen. The starting materials can be added in any order. Alternatively, E) carbamate-functionalized hydrosilane and H) solvent can be added to the reaction vessel. Thereafter, a portion of F) alkenyl-functionalized alkoxysilane can be added, and the contents of the container can be mixed. The starting material G) hydrosilylation reaction catalyst can be dissolved in H) solvent. A portion of the resulting catalyst / solvent solution can be added to the reaction vessel under mixing. Step 2) can be carried out at RT. Alternatively, in step 2), the contents of the reaction vessel can be heated at a temperature of up to 150° C. for a time sufficient to complete the reaction, alternatively at 70° C. for up to 18 hours. Thereafter, one or more additional portions of F) alkenyl-functionalized alkoxysilane can be added, and the catalyst / solvent solution can be added under mixing and heating. Between additions, volatiles may be removed by any convenient means, such as stripping at RT or with heating and optionally reduced pressure.

[0050] Step 2) produces a hydrosilylation reaction product comprising I) the above-mentioned carbamate functionalized alkoxysilanesilane compound. The method may also optionally include one or more additional steps. For example, I) the compound may be recovered from the hydrosilylation reaction product by any convenient means, such as filtering, stripping and / or distillation, optionally accompanied by heating and / or reducing pressure.

[0051] The above method is illustrated in Scheme 1 and Examples 1 and 2 below.

[0052] Scheme 1 - Exemplary Methods for Forming Compounds

[0053] Optional steps and step 1):

[0054]

[0055] Step 2:

[0056]

[0057] The hydrosilylation reaction products prepared by the above method include a combination of compounds having linear and branched linkers (β-adducts and α-adducts, respectively), which combination is represented by D in the formula of the compounds shown above.

[0058] Alternatively, the compound represented by the above formula can be prepared by an alternative method, which comprises:

[0059] 1) Combining starting materials including the following under conditions for achieving a hydrosilylation reaction:

[0060] F) Formula R 3 Si(OR 4 )3 alkenyl-functionalized alkoxysilane, wherein R 3 is alkenyl, and

[0061] R 4 As mentioned above;

[0062] D) ClSiR 2 2H hydrochlorosilane, where R 2 As mentioned above;

[0063] G) a hydrosilylation reaction catalyst; and

[0064] Optional H) solvent;

[0065] Thereby forming a hydrosilylation reaction product, the reaction product comprises:

[0066] E') ClSiR 2 2-D-Si(OR 4 )3 chlorodialkyl((trialkoxysilyl)alkylene)silane; wherein R 2 , D and R 4 As described above; and

[0067] 2) combining starting materials comprising the following under conditions for achieving the reaction:

[0068] E') chlorodialkyl((trialkoxysilyl)alkylene)silane;

[0069] C) carbamate; and

[0070] Optional H) solvent;

[0071] Thereby forming a reaction product comprising:

[0072] I) the above carbamate-functional alkoxysilanesilane compound, and

[0073] J') by-product.

[0074] In this alternative method, C) carbamate can be commercially available, or can be prepared in the same manner as described above in an optional step. When used in this alternative method, the optional step can be performed before or after step 1). However, step 1) of the alternative method includes combining starting materials including the following under conditions for achieving hydrosilylation: F) alkenyl functionalized alkoxysilane, D) hydrochlorosilane, G) hydrosilylation catalyst, and optional H) solvent, each of which is as described above. Step 1) can be performed in a reaction vessel different from the optional step of forming carbamate using the above-mentioned. The starting materials can be added to the container in any order. Step 1) can include mixing and heating the starting materials. Alternatively, H) solvent and F) alkenyl functionalized alkoxysilane can be combined in a reaction vessel under mixing. Hydrochlorosilane can be added, followed by a catalyst / solvent solution (prepared as described above). The contents of the container can be mixed, optionally heated at, for example, 30°C for a time sufficient to achieve the hydrosilylation reaction, for example, up to 72 hours. Alternatively, the reaction mixture may be cooled to control the exothermic hydrosilylation reaction. The resulting hydrosilylation reaction product includes E') chlorodialkyl((trialkoxysilyl)alkylene)silane. The chlorodialkyl((trialkoxysilyl)alkylene)silane may include ClSiR 2 2-D-Si(OR 4 )3; where R 2 , D and R 4 As described above. This may be a mixture D having both linear and branched linkers. The process may optionally further comprise recovering the chlorodialkyl((trialkoxysilyl)alkylene)silane from the hydrosilylation reaction product by any convenient means such as filtering, stripping and / or distillation with heating and / or reduced pressure.

[0075] Step 2) of the alternative method comprises combining starting materials comprising the following under conditions for achieving a reaction: E') a chlorodialkyl((trialkoxysilyl)alkylene)silane prepared as described above; C) the above-described carbamate; and optionally H) a solvent. The solvent may be the same or different from the solvent used in step 1) and / or the optional step (if present). Step 2) may be carried out in the same reaction vessel or a different reaction vessel used for step 1). Step 2) may be carried out, for example, by mixing the carbamate and the solvent (e.g., benzene) in a reaction vessel. The container may be purged with an inert gas such as nitrogen. The chlorodialkyl((trialkoxysilyl)alkyl)silane may be added at RT, for example, intermittently or continuously metered into the reaction vessel until all is added. The reaction vessel may be heated or cooled to control the exothermic hydrosilylation reaction. The resulting mixture may be stirred at RT for a period of time to complete the reaction, for example, up to 18 hours. The reaction product of step 2) comprises I) a carbamate-functionalized alkoxysilanesilane compound and K) a by-product. The process may also comprise one or more additional steps, such as recovery of the compound from the reaction product by any convenient means, such as filtration, stripping and / or distillation at RT or elevated temperature, optionally accompanied by reduced pressure.

[0076] This alternative process is illustrated below in Scheme 2 and Examples 1, 4 and 5, below.

[0077] Scheme 2 - Exemplary methods for making compounds

[0078] Optional steps:

[0079] Step 1):

[0080]

[0081] Step 2):

[0082]

[0083] The reaction products prepared by the above alternative methods include a combination of compounds having linear and branched linkers (beta adducts and alpha adducts, respectively), which combination is represented by D in the formulas of the compounds shown above.

[0084] Preparation of polyalkoxy-functional polyorganosiloxanes using compounds

[0085] The above compounds can be used in a silanization reaction to end-cap the silanol moiety. A method for end-capping the silanol moiety of a polyorganosiloxane comprises: 1) combining starting materials comprising: I) a compound of the above formula; and II) a polyorganosiloxane having a silanol moiety under conditions for achieving a silanization reaction. The method may also include preparing the compound I) by performing the above method prior to step 1). The method produces a reaction product comprising a polyalkoxy-functionalized polyorganosiloxane.

[0086] The polyorganosiloxane II) having a silanol moiety is not particularly limited, provided that the polyorganosiloxane II) has at least one silicon-bonded (HO) group per molecule that is capable of undergoing an end-capping reaction with the carbamate functional group of the compound I). 1 / 2 ) groups. The polyorganosiloxane may be linear, branched, cyclic or resinous. The polyorganosiloxane may include a unit formula: (R 5 3SiO 1 / 2 ) a (R 5 2SiO 2 / 2 ) b (R 5 SiO 3 / 2 ) c (SiO 4 / 2 ) d (HO 1 / 2 ) e , where each R 5 Independently selected from the group consisting of monovalent hydrocarbon groups (e.g., alkyl, alkenyl, and aryl) and monovalent halogenated hydrocarbon groups (e.g., halogenated alkyl, halogenated alkenyl, and halogenated aryl); the subscripts a, b, c, d, and e represent the average number of each unit per molecule and have values ​​such that a≥0, b≥0, c≥0, d≥0, and e≥1 and 2≤(a+b+c+d)≤10,000. Alternatively, the subscript may have values ​​such that 2≤(a+b+c+d)≤2,000; alternatively 2≤(a+b+c+d)≤1,000. R 5 Suitable alkyl groups are as described above for R 2 Description and examples of R 5 Suitable aryl groups are as described above for R 2 Description and examples of R 5 Suitable alkenyl groups are as described above for R 3 As described above, a monovalent halogenated hydrocarbon group is a monovalent hydrocarbon group except that at least one hydrogen atom has been formally replaced by a halogen atom. For example, a halogenated alkyl group includes chloromethyl and fluoromethyl. Alternatively, each R 5 It may be an alkyl group such as methyl or ethyl, or an aryl group such as phenyl. 5 may be selected from methyl and phenyl.5 It may be methyl.

[0087] Alternatively, II) the polyorganosiloxane having a silanol moiety may be a polydiorganosiloxane such as A dihydroxy-terminated polydiorganosiloxane (for example, wherein in the above unit formula, a=c=d=0, b>1, and e=2), wherein R 5 As described above, and the subscript x represents the degree of polymerization, and has an average value of 1 to 2,000, alternatively 1 to 1,000. Alternatively, each R 5 Can be independently selected from the group consisting of alkyl, alkenyl and aryl. 5 It may be an alkyl group such as methyl or ethyl, or an aryl group such as phenyl. 5 may be selected from methyl and phenyl. 5 Methyl may be used. Examples of bishydroxy-terminated polydiorganosiloxanes are:

[0088] i) dihydroxy-terminated polydimethylsiloxane,

[0089] ii) bishydroxy-terminated poly(dimethylsiloxane / methylphenylsiloxane),

[0090] iii) bishydroxy terminated poly(dimethylsiloxane / diphenylsiloxane), or

[0091] viii) A combination of two or more of i) to iii).

[0092] Suitable polyorganosiloxanes having silanol moieties are known in the art and are commercially available. For example, polyorganosiloxane resins having various silanol contents are available from The Dow Chemical Company of Midland, Michigan, USA, such as, for example, Silicone Resins and Intermediates Selection Guide(dow.com) Polydiorganosiloxanes having silanol moieties are also available under the trade name XIAMETER TM OHX polymers were purchased from The Dow Chemical Company, Midland, Michigan, USA. XIAMETER Brand Sealant Formulation Materials for North America(dow.com) An example is described in .

[0093] The compound is used to end-cap the silanol portion of a polyorganosiloxane to produce a polyalkoxy-functional polyorganosiloxane. For example, the end-capped polyorganosiloxane may include a unit formula: (R 5 3SiO 1 / 2 ) a (R 5 2SiO 2 / 2 ) b (R 5 SiO 3 / 2 ) c (SiO 4 / 2 ) d R 6 e , where R 6 is a group of the formula,

[0094] Where R 2 , D, R 4 , R 5 and subscripts a, b, c, d, and e are as described above.

[0095] When the bishydroxy terminated polydiorganosiloxane is end-capped, the resulting polyalkoxy functional polyorganosiloxane comprises the formula:

[0096] The subscripts x and R 5 , R 2 , D and R 4 As described above. The polyalkoxy-functional polyorganosiloxanes described above can be used as crosslinking agents, for example, in moisture-curable polyorganosiloxane compositions.

[0097] Example

[0098] The following 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 set forth in the claims. The starting materials used in these examples are described in Table 1.

[0099] Table 1 - Starting Materials

[0100]

[0101] Example 1 - Synthesis of O-dimethylsilyl-N,N-diethylcarbamate

[0102]

[0103] Under positive N2 pressure and stirring, dichloromethane (100mL) and diethylamine (16.9mL, 12.0g, 164mmol, 2.0 equivalents) were added to a dry 250mL round-bottom flask cooled in an ice bath through a rubber septum. Solid CO2 was carefully added to the mixture until the solution was saturated, and then a solution of dimethylsilyl chloride (10.0mL, 8.52g, 90.0mmol, 1.1 equivalents) in dichloromethane (10mL) was added via a syringe within 10 minutes. CO2 was added regularly over the next 30 minutes, and then the mixture was allowed to warm to room temperature. The mixture was quickly filtered through a disposable glass frit, and dichloromethane was removed under reduced pressure at ambient temperature. The residue was dissolved in hexane and filtered through a disposable glass frit. Hexane was removed under reduced pressure to obtain a crystalline white solid (11.94g, 68.1mmol, 83%). 1 HNMR analysis confirmed the presence of O-dimethylsilyl-N,N-diethylcarbamate.

[0104] Example 2 - Synthesis of dimethyl (2-(trimethoxysilyl)ethyl) silyl diethylcarbamate (ETM-Carbamate-NEt2)

[0105]

[0106] The following procedure was performed in a dry, nitrogen-purged glove box. To a dry 40 mL vial was added O-dimethylsilyl-N,N-diethylcarbamate (2.60 g, 14.8 mmol) and dry toluene (25 mL). To this solution was added vinyltrimethoxysilane (1.25 mL, 8.15 mmol, 0.55 eq.), and the mixture was stirred (magnetic stirrer). A toluene solution of Castel's catalyst ("Pt solution", 2.5 wt. % Pt, 10.4 μL) was added. The mixture was stirred at 70 °C for 3 hours, and the progress of the reaction was monitored by gas chromatography. A second portion of vinyltrimethoxysilane (1.25 mL, 8.15 mmol, 55 eq.) was then added, and the mixture was stirred at 70 °C for 18 hours. An additional volume of Pt solution (10.4 μL) was added, and the mixture was stirred at 70 °C for 6 hours. An additional volume of Pt solution (10.4 μL) was added, and the mixture was stirred at 70 °C for 18 hours. The volatiles were removed under reduced pressure at RT. 1 H NMR, 13 C NMR and GC showed the reaction was complete to form about a 9:1 mixture of β / α hydrosilylation products (dimethyl(2-(trimethoxysilyl)ethyl)silyldiethylcarbamate) and about 15%-25% unreacted dimethylhydrosilyldiethylcarbamate.

[0107] Preparation Example 3 - Synthesis of Chlorodimethyl((trimethoxysilyl)ethyl)silane

[0108]

[0109] The following procedure was carried out in a dry, nitrogen-purged glove box. Into a dry 250 mL round-bottom flask was loaded dry toluene (100 mL) and vinyl trimethoxysilane (8.3 mL, 8.0 g, 54 mmol). Dimethylchlorosilane (6.6 mL, 5.6 g, 59 mmol, 1.1 equivalents) was added to the stirred solution, followed by a toluene solution of the Custer catalyst (2.5 wt % Pt, 22.5 μL). The mixture was stirred at 30 ° C for 72 hours, then filtered through an alumina pad. Toluene was removed under reduced pressure at ambient temperature. 1 H and 13 C NMR spectrum and GC showed no residual vinyltrimethoxysilane or dimethylchlorosilane, and confirmed that the product contained about 14% by weight of toluene and was a mixture of β-addition product (86%) and α-addition product (14%). The mass of the product was 15.0 g (12.6 g, 84% by weight, 51.9 mmol, 96%).

[0110] Example 4 - Synthesis of dimethyl (2-(trimethoxysilyl)ethyl) silyl dimethylcarbamate (ETM-Carbamate-NMe2)

[0111]

[0112] The following procedure was performed in a dry, nitrogen-purged glove box. Pure chlorodimethyl(2-(trimethoxysilyl)ethyl)silane (2.5 mL, 8.44 mmol) prepared as described in Example 3 with a purity of 84% was added dropwise to a stirred solution of dimethylammonium dimethylcarbamate (1.4 mL, 11.0 mmol, 1.3 equiv) in dry benzene (20 mL) in a dry 40 mL vial at ambient temperature over about 2 minutes. The mixture was stirred for 18 hours. The mixture was filtered and the filtrate was placed under vacuum to give a light brown liquid. The liquid was diluted with hexanes (8 mL) and filtered through a 0.45 μm PTFE filter. The filtrate was placed under vacuum to give a colorless liquid, and 1 H NMR confirmed the presence of dimethyl(2-(trimethoxysilyl)ethyl)silyldimethylcarbamate as a mixture of beta and alpha addition products.

[0113] Example 5 - Synthesis of dimethyl (2-(trimethoxysilyl)ethyl)silylcarbamate (ETM-amino Formate-NH2)

[0114]

[0115] The following procedure was performed in a dry, nitrogen-purged glove box. Chlorodimethyl(2-(trimethoxysilyl)ethyl)silane (approximately 2.5 mL, 2.44 g, 2.05 g of 84% purity by weight, 8.44 mmol) prepared in Example 3 was added dropwise via syringe over 2 minutes at ambient temperature to a vigorously stirred suspension of ammonium carbamate (1.002 g, 12.8 mmol, 1.5 eq.) in dry benzene (20 mL). After stirring at ambient temperature for 1 hour, the mixture was filtered through a frit. The filtrate was placed under vacuum to give a light brown oil, and 1 HNMR confirmed the presence of dimethyl (2-(trimethoxysilyl)ethyl)silylcarbamate (1.70 g, 6.34 mmol, 75%).

[0116] Example 6 - Hydroxyl-terminated polydimethylsiloxane end-capping

[0117]

[0118] PDMS-OH and the capping agent prepared as described in one of Examples 2, 4 and 5 above were loaded into a dental cup. After mixing on a high-speed mixer for 5 minutes, the reaction mixture was kept in a sealed container or under vacuum at room temperature. 1 The progress of the reaction was monitored by HNMR by the disappearance of the SiOH moiety. When the reaction was complete, 29 Si NMR confirmed the formation of bistrialkoxy terminated PDMS.The viscosity of the terminated polydimethylsiloxane was measured by ARES rheometer (25 mm parallel cone and plate, cone angle 0.0999 radians, gap 0.0508 mm, test was a steady rate scan from 0.1 1 / s to 10 1 / s, 10 points per decade).

[0119]

[0120] Industrial Applicability

[0121] The above examples show that carbamate-functionalized alkoxysilylalkylenesilane compounds can be successfully prepared by the methods described herein. These examples further show that the compounds can be successfully used to end-cap the silanol moiety of polyorganosiloxanes. These examples show that a wide range of polyalkoxy-functionalized polyorganosiloxanes can be prepared by end-capping different commercially available silanol-functionalized polyorganosiloxanes with the carbamate-functionalized polyalkoxysilylalkylenesilane compounds of the present invention, due to the ready availability of various polyorganosiloxanes having silanol moieties, which can be, for example, linear, branched or resinous. The carbamate-functionalized alkoxysilylalkylenesilane compounds undergo a silylation reaction to end-cap the silanol moieties, with one or more of the following benefits: the reaction is carried out at RT without the addition of a catalyst, there is no viscosity increase or the viscosity increase is relatively low; and the product can be clear (not turbid).

[0122] Definition and Use of Terms

[0123] Unless otherwise indicated by the context of this specification, all quantities, ratios and percentages herein are by weight; the articles "a", "an" and "the" each refer to one (a kind) or more (a variety); and the singular includes the plural. The Summary of the Invention and the Abstract are hereby incorporated by reference. The terms "comprising" or "containing" are used in their 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 exemplary examples is not meant to be limited to the listed examples. Therefore, "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.

[0124] "Yield" refers to the molar amount of carbamate-functional alkoxysilylalkylenesilane compound produced / the molar amount of carbamate-functional alkoxysilylalkylenesilane compound possible based on the amount of limiting reagent. "Selectivity" refers to the ratio of linear isomers / branched isomers of the carbamate-functional alkoxysilylalkylenesilane compound (where the isomers have the same molecular weight).

[0125] Abbreviations used herein have the definitions in Table 4.

[0126] Table 4 - Abbreviations

[0127]

[0128]

[0129] Test Method

[0130] The GC test method used in this application was performed as follows: Chromatograms were recorded using two methods. (1) (The chromatographic equipment consisted of a Hewlett Packard 5890 Series II GC equipped with a flame ionization detector and a Hewlett Packard 6890 Series autosampler. Separation was performed using a 30m HP-5 column with a helium flow rate of 78mL / min and a column flow rate of 1.05mL / min. The sample was prepared as 100μL in 1mL of dichloromethane. Data were collected for 36.33 minutes using an injection volume of 2μL, an injector temperature of 180°C and a detector temperature of 300°C. The oven method consisted of maintaining an initial temperature of 40°C for 1 minute, followed by a temperature increase of 5°C / min to 150°C, a temperature increase of 15°C / min to 275°C, and ending with a final temperature of 275°C for 5 minutes.) (2). An Agilent Technologies 7896A GC system was equipped with a 7693 autosampler and connected to a 5975C mass spectrometer. Column: Agilent DB-5MS (phenyl-arylene, 30 m x 250 μm x 0.25 μm). Inlet temperature: 250°C. Oven program: 50°C for 1 min; ramp to 275°C at 10°C / min; hold at 275°C for 5 min. Total run time: 28.5 min. Mass spectrometer operated in chemical ionization mode / positive ion mode with methane as reagent gas. Mass range: 50-1000. Solvent delay: 3.5 min.

[0131] The NMR measurement method used in this application was performed as follows: (Protons were recorded on an Agilent 500-MR or Varian NMR spectrometer operating at 500 MHz) 1 H) and 13 C nuclear magnetic resonance (NMR) spectra. Carbon ( 13 C) and silicon wafer ( 29 Si) NMR spectrum. Peak frequencies are reported in ppm. 1 H samples were run with 100 μL of sample in 1 mL of deuterated chloroform (CDCl3) or benzene (C6D6), while 29 Si and 13 C samples were run with 2 mL of sample in 3 mL of deuterated chloroform containing Cr(acac)3. 1 H NMR spectra were internally referenced to residual protons in the deuterated solvent. 13 C NMR spectra were internally referenced to deuterated solvents.

Claims

1. A carbamate-functionalized alkoxysilanesilane compound comprising the formula: in Each R 1 are independently selected from the group consisting of a hydrogen atom and an alkyl group having 1 to 6 carbon atoms, provided that R 1 Two instances of can be bonded together to form a cyclic secondary amine moiety; Each R 2 independently selected from the group consisting of alkyl and aryl; D is alkylene; and Each R 4 is an independently selected alkyl group having 1 to 6 carbon atoms.

2. The compound according to claim 1, wherein each R 1 is selected from the group consisting of hydrogen, methyl and ethyl.

3. The compound according to claim 1 or claim 2, wherein each R 2 It's methyl.

4. A compound according to any one of claims 1 to 3, wherein each D is selected from Composed of groups.

5. A compound according to any one of claims 1 to 4, wherein each R 4 It's methyl.

6. A method for preparing a carbamate-functionalized alkoxysilanesilane compound according to any one of claims 1 to 5, wherein the method comprises: 1) Combining starting materials comprising the following under conditions for achieving a reaction: C) carbamate; and D) ClSiR 2 2H hydrochlorosilane, where R 2 As mentioned above; Thereby forming a reaction product, the reaction product comprising: E) Formula R 1 2NC(=O)O-SiR 2 2H carbamate functionalized silane, Where R 1 and R 2 As described above; and 2) combining starting materials comprising the following under conditions for achieving a hydrosilylation reaction: E) the carbamate-functional hydridosilane; F) Formula R 3 Si(OR 4 )3 alkenyl-functionalized alkoxysilane, wherein R 3 is alkenyl, and R 4 As mentioned above; G) a hydrosilylation reaction catalyst; Optional H) solvent; Thereby forming a hydrosilylation reaction product, the reaction product comprises: I) the carbamate-functionalized alkoxysilanesilane compound, and J) By-products.

7. The method according to claim 6, wherein each R 1 It is methyl or ethyl.

8. A method for preparing a carbamate-functionalized alkoxysilanesilane compound according to any one of claims 1 to 5, wherein the method comprises: 1) Combining starting materials including the following under conditions for achieving a hydrosilylation reaction: F) Formula R 3 Si(OR 4 )3 alkenyl-functionalized alkoxysilane, wherein R 3 is alkenyl, and R 4 As mentioned above; D) ClSiR 2 2H hydrochlorosilane, where R 2 As mentioned above; G) a hydrosilylation reaction catalyst; and Optional H) solvent; Thereby forming a hydrosilylation reaction product, the reaction product comprises: E') includes the formula ClSiR 2 2-D-Si(OR 4 )3 chlorodialkyl((trialkoxysilyl)alkylene)silane; wherein R 2 , D and R 4 As described above; and 2) combining starting materials comprising the following under conditions for achieving the reaction: E') the chlorodialkyl((trialkoxysilyl)alkylene)silane; C) carbamate; and Optional H) solvent; Thereby forming a reaction product, the reaction product comprising: I) the carbamate-functionalized alkoxysilanesilane compound, and J') by-product.

9. The method according to claim 8, wherein each R 1 It's a hydrogen atom.

10. A method for preparing a polyalkoxy-functional polyorganosiloxane, wherein the method comprises: i) carrying out the method according to any one of claims 6 to 9, thereby forming I) the carbamate-functional alkoxysilanesilane compound; ii) combining starting materials comprising: I) the carbamate-functional alkoxysilanesilane compound; and II) Polyorganosiloxanes having silanol moieties.

11. A method for preparing a polyalkoxy-functional polyorganosiloxane, wherein the method comprises: 1) combining starting materials comprising: I) a carbamate-functional alkoxysilanesilane compound according to any one of claims 1 to 5 under conditions for achieving a capping reaction; and II) Polyorganosiloxanes having silanol moieties.

12. The method according to claim 10 or claim 11, wherein II) the polyorganosiloxane is of formula A bishydroxy-terminated polydiorganosiloxane, wherein each R 5 are independently selected from the group consisting of an alkyl group, an alkenyl group, and an aryl group, and the subscript x represents a degree of polymerization and has an average value of 1 to 2,000.

13. The method of claim 12, wherein the bis-hydroxy terminated polydiorganosiloxane is a bis-hydroxy terminated polydimethylsiloxane.

14. A polyalkoxy-functional polyorganosiloxane prepared by the method according to claim 12, wherein the polyalkoxy-functional polyorganosiloxane comprises the formula: The subscripts x and R 5 , R 2 , D and R 4 As mentioned above.

15. Use of the polyalkoxy-functional polyorganosiloxane according to claim 14 in a condensation-reaction-curable polyorganosiloxane composition.

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