Patent Description:
Polyorganosiloxane compositions that cure to elastomeric materials are well known. Such compositions may be prepared by mixing polydiorganosiloxanes having curable (e.g., hydrolyzable, radiation curable, or heat curable) groups with crosslinking agents and/or catalysts, as needed. Generally, the polydiorganosiloxanes may have <NUM> to <NUM> reactive groups per chain end. Compositions including these components can then be cured, for example, by exposure to atmospheric moisture.

Furthermore, to show utility for certain applications, such as silicone adhesive applications, a filler may be added to the polyorganosiloxane composition to improve the physical property profile (e.g., increase tensile strength and increase % elongation to break) of the resulting cured product of the composition. Other properties such as adhesion and dispensability also play a role in the performance and commercial acceptance of a composition for adhesive applications.

With respect to dispensability, resins are typically included in silicone adhesive applications to make the compositions more flowable, and thus may reduce stringing of the adhesive composition, for example, as it is dispensed through a fine tip applicator. These resins may be non-reactive in the composition (i.e., are non-reactive resins) or may reactive (i.e., are reactive resins) and react with other components of the composition, such as during the curing process.

It is an object of the present invention to provide a novel reactive resin and polymer that may be introduced to a silicone adhesive composition and provide additional benefits in terms of flowability, improved mechanical properties and cure response.

The present invention discloses an alkoxy-functional organopolysiloxane resin and polymer that comprises the reaction product of a reaction of (i) an alkenyl-functional siloxane resin comprising R<NUM>SiO<NUM>/<NUM> units and SiO<NUM>/<NUM> units, (ii) an alkoxysilane-functional organosiloxane compound having at least one silicon-bonded hydrogen atom at a molecular terminal; (iii) an endcapper, and (iv) a polyorganosiloxane having an average, per molecule, of at least <NUM> aliphatically unsaturated organic groups in the presence of a (v) hydrosilylation catalyst.

In this invention, each R of the alkenyl-functional siloxane resin is independently a monovalent hydrocarbon radical having <NUM> to <NUM> carbon atoms with the proviso that at least one R is an alkenyl radical. In addition, the molar ratio of the R<NUM>SiO<NUM>/<NUM> units to SiO<NUM>/<NUM> units has a value ranging from <NUM>/<NUM> to <NUM>/<NUM>.

The endcapper (iii) of the present invention is according to the formula to the formula R<NUM><NUM>SiO-(R<NUM><NUM>SiO)s-SiR<NUM><NUM>H or R<NUM><NUM>SiO-(R<NUM><NUM>SiO)t-(HR<NUM>SiO)-SiR<NUM><NUM>, or combinations thereof, wherein each R<NUM> is independently a hydrocarbon radical and wherein the subscripts s and t independently have values ranging from <NUM> to <NUM>.

The alkoxy-functional organopolysiloxane resin and polymer of the present invention may be utilized in a wide variety of silicone adhesive applications. The alkoxy-functional organopolysiloxane polymer and resin aids in the dispensability of these adhesives, and also provides reactive functionality that is capable of moisture cure.

The articles 'a', 'an', and 'the' each refer to one or more, unless otherwise indicated. All amounts, ratios, and percentages in this application are by weight, unless otherwise indicated. All kinematic viscosities were measured at <NUM>, unless otherwise indicated.

The present invention is directed to a reactive resin and polymer that may be utilized in adhesive applications, such as silicone adhesive compositions.

In certain embodiments, the reactive resin and polymer is an alkoxy-functional organopolysiloxane resin and polymer that comprises the reaction product of a reaction of:.

in the presence of a (v) hydrosilylation catalyst.

The alkenyl-functional siloxane compound (i), in certain embodiments, includes a resinous portion wherein the R<NUM>SiO<NUM>/<NUM> units (i.e., "M" units) are bonded to the SiO<NUM>/<NUM> units (i.e., "Q" units), each of which is bonded to at least one other SiO<NUM>/<NUM> unit. In the R<NUM>SiO<NUM>/<NUM> units, as noted above, each R is individually a monovalent hydrocarbon radical having less than <NUM> carbon atoms, with the proviso that at least one R is an alkenyl radical. Examples of suitable R radicals include alkyl radicals, such as methyl, ethyl, propyl, and pentyl; alkenyl radicals, such as vinyl, alkyl, and <NUM>-hexenyl; and aryl radicals such as phenyl.

At least one third, and more preferably substantially all R radicals, are methyl radicals, with the proviso that at least one R radical is an alkenyl radical, and further with the proviso that the resin (i) ranges from <NUM> to <NUM> weight percent, alternatively from <NUM> to <NUM> weight percent, alkenyl-functionality, based on the total weight of the resin (i). Stated differently, the alkenyl radical content of the resin (i) ranges from. <NUM> to <NUM> weight percent of the total weight of the resin (i). Examples of preferred R<NUM>SiO<NUM>/<NUM> units having methyl radicals include Me<NUM>SiO<NUM>/<NUM> units and PhMe<NUM>SiO<NUM>/<NUM> units, wherein Me is methyl and Ph is phenyl.

In addition, in certain embodiments, the silanol content of the resin (i) is less than <NUM> weight percent of the total weight of the resin (i). The term "silanol content", as defined herein, refers to the weight percent of silicon-hydroxy groups in the particular molecule in which they are included, and here defined as the total weight percent of silicon-hydroxy groups in the resin (i) (i.e., the weight percent of Si-OH groups in the resin).

For the purposes of the present invention, the ratio of R<NUM>SiO<NUM>/<NUM> units to SiO<NUM>/<NUM> units in resin (i) has a molar ratio of <NUM>:<NUM> to <NUM>:<NUM>, respectively. It is preferred that the molar ratio of the total M units to total Q units of the resin (i) be between <NUM>:<NUM> and <NUM>:<NUM>. The above M/Q molar ratios can be easily obtained by <NUM>Si nuclear magnetic resonance (NMR) spectroscopy.

The resin (i) preferably has a weight average molecular weight Mw ranging from <NUM>,<NUM> to <NUM>,<NUM>/mole (Daltons), alternatively from <NUM>,<NUM> and <NUM>,<NUM>/mole.

The alkoxysilane-functional organosiloxane compound having at least one silicon-bonded hydrogen atom at a molecular terminal (ii), in certain embodiments, is of the general formula HSi(R<NUM>)<NUM>OSi(R<NUM>)<NUM>CH<NUM>CH<NUM>SiR<NUM>z(OR<NUM>)<NUM>-z, wherein each R is independently a monovalent hydrocarbon having <NUM> to <NUM> carbon atoms and wherein the subscript z is <NUM> or <NUM>.

Alternatively, the alkoxysilane-functional organosiloxane compound having at least one silicon-bonded hydrogen atom at a molecular terminal (ii) is of the general formula HSi(Me)<NUM>OSi(Me)<NUM>CH<NUM>CH<NUM>Si(OMe)<NUM>, wherein Me is methyl.

Component (iii) is an endcapper. The endcapper may be a polydiorganosiloxane having one silicone-bonded hydrogen atom per molecule. An exemplary endcapper may have the formula (I), formula (II), or a combination thereof. Formula (I) is R<NUM><NUM>SiO-(R<NUM><NUM>SiO)s-SiR<NUM><NUM>H. Each R<NUM> is as described above and is independently a monovalent hydrocarbon group exemplified by alkyl such as methyl, ethyl, propyl, butyl, pentyl, and hexyl; and aryl such as phenyl, tolyl, xylyl and benzyl; and subscript s has a value ranging from <NUM> to <NUM>, alternatively <NUM> to <NUM>, and alternatively <NUM>. Formula (II) is R<NUM><NUM>SiO-(R<NUM><NUM>SiO)t-(HR<NUM>SiO)-SiR<NUM><NUM>. In this formula, each R<NUM> is as described above and is independently a monovalent hydrocarbon group exemplified by alkyl such as methyl, ethyl, propyl, butyl, pentyl, and hexyl; and aryl such as phenyl, tolyl, xylyl and benzyl. Subscript t has a value ranging from <NUM> to <NUM>, alternatively <NUM>.

Component (iv) is a polyorganosiloxane having an average, per molecule, of at least <NUM> aliphatically unsaturated organic groups, which are capable of undergoing a hydrosilylation reaction with a silicon bonded hydrogen atom of component (ii). Component (iv) may have a linear or branched structure. Alternatively, component (iv) may have a linear structure. Component (iv) may be a combination comprising two or more polyorganosiloxanes that differ in at least one of the following properties: structure, viscosity, degree of polymerization, and sequence.

Component (iv) has a minimum average degree of polymerization (average DP) of <NUM>. Alternatively, average DP of component (iv) may range from <NUM> to <NUM>. The distribution DP of polyorganosiloxanes of component (iv) can be bimodal. For example, component (iv) may comprise one alkenyl terminated polydiorganosiloxane with a DP of <NUM> and another alkenyl terminated polydiorganosiloxane with a DP higher than <NUM>, provided that average DP of the polydiorganosiloxanes ranges from <NUM> to <NUM>. However, suitable polyorganosiloxanes for use in component (iv) have a minimum degree of polymerization (DP) of <NUM>, provided that polyorganosiloxanes with DP less than <NUM> are combined with polyorganosiloxanes having DP greater than <NUM>. Suitable polydiorganosiloxanes for component (iv) are known in the art and are commercially available. For example, Dow Corning® SFD-<NUM> has DP ranging from <NUM> to <NUM>, Dow Corning SFD-<NUM> has DP ranging from <NUM> to <NUM>, Dow Corning® <NUM> has DP of <NUM>, and Dow Corning® SFD-<NUM> has DP of <NUM>. All of these are vinyl-terminated polydimethylsiloxanes are commercially available from Dow Corning Corporation of Midland, Michigan, USA. When component (iv) has a bimodal distribution, the polyorganosiloxane with the lower DP (low DP polyorganosiloxane) is present in a lower amount than the polyorganosiloxane with the higher DP (high DP polyorganosiloxane). For example, in a bimodal distribution, the ratio of low DP polyorganosiloxane/high DP polyorganosiloxane may range from <NUM>/<NUM> to <NUM>/<NUM>.

Component (iv) is exemplified by polyorganosiloxanes of formula (I), formula (II), or a combination thereof. In certain embodiments, Formula (I) is R<NUM><NUM>R<NUM>SiO(R<NUM><NUM>SiO)a(R<NUM>R<NUM>SiO)bSiR<NUM><NUM>R<NUM>, and formula (II) is R<NUM><NUM>SiO(R<NUM><NUM>SiO)c(R<NUM>R<NUM>SiO)dSiR<NUM><NUM>. In these formulae, each R<NUM> is independently a monovalent organic group free of aliphatic unsaturation; each R<NUM> is independently an aliphatically unsaturated organic group; subscript a has an average value ranging from <NUM> to <NUM>; subscript b has an average value ranging from <NUM> to <NUM>; subscript c has an average value ranging from <NUM> to <NUM>; and subscript d has an average value ranging from <NUM> to <NUM>. In formulae (I) and (II), <NUM> ≤ (a + b) ≤<NUM> and <NUM> ≤ (c + d) ≤ <NUM>.

Suitable monovalent organic groups for R<NUM> include, but are not limited to, monovalent hydrocarbon groups exemplified by alkyl such as methyl, ethyl, propyl, butyl, pentyl, octyl, undecyl, and octadecyl; cycloalkyl such as cyclohexyl; and aryl such as phenyl, tolyl, xylyl, benzyl, and <NUM>-phenylethyl. Each R<NUM> is independently an aliphatically unsaturated monovalent organic group. R<NUM> may be an aliphatically unsaturated monovalent hydrocarbon group exemplified by alkenyl groups such as vinyl, allyl, propenyl, and butenyl; and alkynyl groups such as ethynyl and propynyl.

Component (iv) may comprise a polydiorganosiloxane such as i) dimethylvinylsiloxy-terminated polydimethylsiloxane, ii) dimethylvinylsiloxy-terminated poly(dimethylsiloxane/methylvinylsiloxane), iii) dimethylvinylsiloxy-terminated polymethylvinylsiloxane, iv) trimethylsiloxy-terminated poly(dimethylsiloxane/methylvinylsiloxane), v) trimethylsiloxy-terminated polymethylvinylsiloxane, vi) dimethylvinylsiloxy-terminated poly(dimethylsiloxane/methylphenylsiloxane), vii) dimethylvinylsiloxy-terminated poly(dimethylsiloxane/diphenylsiloxane), viii) phenyl, methyl, vinyl-siloxy-terminated polydimethylsiloxane, ix) dimethylhexenylsiloxy-terminated polydimethylsiloxane, x) dimethylhexenylsiloxy-terminated poly(dimethylsiloxane/methylhexenylsiloxane), xi) dimethylhexenylsiloxy-terminated polymethylhexenylsiloxane, xii) trimethylsiloxy-terminated poly(dimethylsiloxane/methylhexenylsiloxane), orxiii) a combination thereof.

Component (v) is a hydrosilylation catalyst which accelerates the reaction of components (i)-(iv). Component (v) may be added in an amount sufficient to promote the reaction of components (i)-(iv), and this amount may be, for example, sufficient to provide <NUM> parts per million (ppm) to <NUM> ppm of platinum group metal, alternatively <NUM> ppm to <NUM> ppm, alternatively <NUM> ppm to <NUM>, alternatively <NUM> ppm to <NUM> ppm, based on the combined weight of all components used in the process.

Suitable hydrosilylation catalysts (v) are known in the art and commercially available. Component (v) may comprise a platinum group metal selected from platinum (Pt), rhodium, ruthenium, palladium, osmium or iridium metal or organometallic compound thereof, or a combination thereof. Component (v) is exemplified by compounds such as chloroplatinic acid, chloroplatinic acid hexahydrate, platinum dichloride, and complexes of said compounds with low molecular weight organopolysiloxanes or platinum compounds microencapsulated in a matrix or coreshell type structure. Complexes of platinum with low molecular weight organopolysiloxanes include <NUM>,<NUM>-diethenyl-<NUM>,<NUM>,<NUM>,<NUM> -tetramethyldisiloxane complexes with platinum. Alternatively, the catalyst may comprise <NUM>,<NUM>-diethenyl-<NUM>,<NUM>,<NUM>,<NUM> - tetramethyldisiloxane complex with platinum. When the catalyst is a platinum complex with a low molecular weight organopolysiloxane, the amount of catalyst may range from <NUM> % to <NUM> % based on the combined weight of the components used in the process.

Suitable hydrosilylation catalysts for component (v) are described in, for example, <CIT>; <CIT>; <CIT>; <CIT>; <CIT>; <CIT>; <CIT>; <CIT>; <CIT>; and <CIT> and <CIT>.

In certain embodiments, the alkenyl content (i.e., the vinyl content) of the reactive resin and polymer, contributed from components (i) and (iv), comprises from <NUM> to <NUM> weight percent, alternatively <NUM> to <NUM> weight percent, of the total weight of the reactive resin and polymer.

In certain embodiments, the silanol content of the reactive resin and polymer, contributed from component (ii), comprises from <NUM> to <NUM> weight percent, alternatively <NUM> to <NUM> weight percent, of the total weight of the reactive resin and polymer.

In certain embodiments, the reactive resin and polymer is formulated wherein at most <NUM> weight% of the alkenyl radicals of the resin (i) react with the silicon-bonded hydrogen atoms of the compound (ii). In certain embodiments, the reactive resin and polymer is formulated wherein at least <NUM> weight% of the alkenyl radicals of the resin (i) react with the silicon-bonded hydrogen atoms of the endcapper (iii).

In addition to components (i)-(v), the reactive resin and polymer may include other optional components. Suitable additional components that may be utilized include, but are not limited to, (vi) an acid scavenger, (vii) a colorant, (viii) a resin treatment agent, (ix) a corrosion inhibitor, (x), an adhesion promoter, and combinations thereof.

Component (vi) is an acid scavenger. Suitable acid scavenger may comprise a metal oxide such as magnesium oxide. Acid scavengers are known in the art and are commercially available under tradenames including Rhenofit F, Star Mag CX-<NUM>, Star Mag CX-<NUM>, BLP-<NUM>, and MaxOx98LR. Rhenofit F was calcium oxide from Rhein Chemie Corporation of Chardon, OH, USA. Star Mag CX-<NUM> was magnesium oxide from Merrand International Corp. of Portsmouth, NH, USA. MagOX 98LR was magnesium oxide from Premier Chemicals LLC of W. Conshohocken, PA, USA. BLP-<NUM> was calcium carbonate was Omya Americas of Cincinnati, OH, USA. The amount of acid scavenger (vi) may range from <NUM> % to <NUM> % based on the total weight of the reactive resin and polymer.

Component (vii) is a colorant (e.g., dye or pigment). Examples of suitable colorants include carbon black, Stan-Tone 40SP03 Blue (which is commercially available from PolyOne) and Colorant BA <NUM> Iron Oxide pigment (which is commercially available from Cathay Pigments (USA), Inc. Valparaiso, IN <NUM> USA). Examples of colorants are known in the art and are disclosed in <CIT>; <CIT>; and <CIT>. The amount of colorant added to the reactive resin and polymer depends on various factors including the other components of the composition, and the type of colorant selected, however, the amount may range from <NUM> % to <NUM> % based on the total weight of the reactive resin and polymer.

Component (viii) is a resin treatment agent. Suitable resin treatment agents may be of the formula R<NUM>Si(OR<NUM>)<NUM> or (R<NUM><NUM>Si)<NUM>NH, and combinations thereof, wherein each R is independently a monovalent hydrocarbon radical having <NUM> to <NUM> carbon atoms. When utilized, the resin treatment agent comprises less than <NUM>% of the total weight of reactive resin and polymer.

Component (ix) is a corrosion inhibitor. Examples of suitable corrosion inhibitors include benzotriazole, mercaptabenzotriazole, mercaptobenzothiazole, and commercially available corrosion inhibitors such as <NUM>,<NUM>-dimercapto-<NUM>,<NUM>,<NUM>-thiadiazole derivative (CUVAN® <NUM>) and alkylthiadiazole (CUVAN® <NUM>) from R. Vanderbilt. The amount of component (ix) may range from <NUM>% to <NUM>% based on the total weight of the reactive resin and polymer.

Component (x) is an adhesion promoter. Examples of suitable adhesion promoters include an alkoxysilane such as an epoxy-functional alkoxysilane, or a mercapto-functional compound; a combination of an alkoxysilane and a hydroxy-functional polyorganosiloxane; a mercapto-functional compound; an unsaturated compound; an epoxy-functional silane; an epoxy-functional siloxane; a combination, such as a reaction product, of an epoxy-functional silane or epoxy-functional siloxane and a hydroxy-functional polyorganosiloxane; or a combination thereof. Suitable adhesion promoters are known in the art and are commercially available. For example, Silquest® A186 is beta-(<NUM>,<NUM>-epoxycyclohexyl)ethyltrimethoxysilane which is commercially available from Crompton OSi Specialties of Middlebury, Connecticut, USA. CD9050 is a monofunctional acid ester useful as an adhesion promoter that provides adhesion to metal substrates and is designed for radiation curable compositions. CD9050 is commercially available from Sartomer Co. SR489D is tridecyl acrylate, SR395 is isodecyl acrylate, SR257 is stearyl acrylate, SR506 is isobornyl acrylate, SR833S is tricyclodecane dimethanol diacrylate, SR238 is <NUM>,<NUM> hexanediol diacrylate, and SR351 is trimethylol propane triacrylate, all of which are also commercially available from Sartomer Co. The amount of adhesion promoter (x) added to the reactive resin and polymer depends on various factors including the specific adhesion promoter selected, the other components of the reactive resin and polymer, and the end use of the reactive resin and polymer, however, the amount may range from <NUM> % to <NUM> % based on the total weight of the reactive resin and polymer. Other suitable adhesion promoters, which are useful to promote adhesion to metals, include maleic anhydride, methacrylic anhydride, and glycidyl methacrylate.

Component (x) can be an unsaturated or epoxy-functional compound. Suitable epoxy-functional compounds are known in the art and commercially available, see for example, <CIT>; <CIT>; <CIT>; and <CIT> (at col. <NUM>-<NUM>). Component (g) may comprise an unsaturated or epoxy-functional alkoxysilane. For example, the functional alkoxysilane can have the formula R<NUM>vSi(OR<NUM>)(<NUM>-v), where subscript v is <NUM>, <NUM>, or <NUM>, alternatively v is <NUM>.

Each R<NUM> is independently a monovalent organic group with the proviso that at least one R<NUM> is an unsaturated organic group or an epoxy-functional organic group. Epoxy-functional organic groups for R<NUM> are exemplified by <NUM>-glycidoxypropyl and (epoxycyclohexyl)ethyl. Unsaturated organic groups for R<NUM> are exemplified by <NUM>-methacryloyloxypropyl, <NUM>-acryloyloxypropyl, and unsaturated monovalent hydrocarbon groups such as vinyl, allyl, hexenyl, undecylenyl.

Each R<NUM> is independently an unsubstituted, saturated hydrocarbon group of <NUM> to <NUM> carbon atoms, alternatively <NUM> to <NUM> carbon atoms. R<NUM> is exemplified by methyl, ethyl, propyl, and butyl.

Examples of suitable epoxy-functional alkoxysilanes include <NUM>-glycidoxypropyltrimethoxysilane, <NUM>-glycidoxypropyltriethoxysilane, (epoxycyclohexyl)ethyldimethoxysilane, (epoxycyclohexyl)ethyldiethoxysilane and combinations thereof. Examples of suitable unsaturated alkoxysilanes include vinyltrimethoxysilane, allyltrimethoxysilane, allyltriethoxysilane, hexenyltrimethoxysilane, undecylenyltrimethoxysilane, <NUM>-methacryloyloxypropyl trimethoxysilane, <NUM>-methacryloyloxypropyl triethoxysilane, <NUM>-acryloyloxypropyl trimethoxysilane, <NUM>-acryloyloxypropyl triethoxysilane, and combinations thereof. Alternatively, examples of suitable adhesion promoters include glycidoxypropyltrimethoxysilane and a combination of glycidoxypropyltrimethoxysilane with an aluminum chelate or zirconium chelate.

Component (x) may comprise an epoxy-functional siloxane such as a reaction product of a hydroxy-terminated polyorganosiloxane with an epoxy-functional alkoxysilane, as described above, or a physical blend of the hydroxy-terminated polyorganosiloxane with the epoxy-functional alkoxysilane. Component (x) may comprise a combination of an epoxy-functional alkoxysilane and an epoxy-functional siloxane. For example, component (x) is exemplified by a mixture of <NUM>-glycidoxypropyltrimethoxysilane and a reaction product of hydroxy-terminated methylvinylsiloxane with <NUM>-glycidoxypropyltrimethoxysilane, or a mixture of <NUM>-glycidoxypropyltrimethoxysilane and a hydroxy-terminated methylvinylsiloxane, or a mixture of <NUM>-glycidoxypropyltrimethoxysilane and a hydroxy-terminated methylvinyl/dimethylsiloxane copolymer. When used as a physical blend rather than as a reaction product, these components may be stored separately in multiple-part kits.

Suitable mercapto-functional compounds include an organomercaptan, a mercapto containing silane, or a combination thereof. Suitable mercapto containing silanes include <NUM>-mercaptopropyltrimethoxysilane. Suitable mercapto-functional compounds are disclosed in <CIT>. One skilled in the art would recognize that certain components described herein may be added to the composition for more than one or different purposes. For example, alkoxysilanes may be use as adhesion promoters, filler treating agents, and/or as crosslinking agents in condensation reaction curable silicone compositions.

The reactive resin may be formed by one of two methods.

In the first method, the so-called sequential addition method, the resin (i) and endcapper (iii) and alkenyl-functional polyorganosiloxane (iv) are premixed to homogeneity, wherein the hydrosilylation catalyst (v) is added and the product is mixed again to homogeneity, wherein the catalyst (v) begins to catalyze the reaction of the resin (i) and endcapper (iii). The temperature is raised to temperature sufficient to achieve reaction of the resin (i) and endcapper (iii), such as to between <NUM> and <NUM>, such as <NUM>. Next, the alkoxy-functional organosiloxane compound (ii) is added and the mixture is allowed to continue to react at a maximum of <NUM> for a predetermined period of time, such as <NUM> minutes. At this point, the product was stripped at full vacuum at a temperature sufficient to remove any excess endcapper (iii), such as at <NUM> for <NUM> minutes.

In the second method, or all-in-one method, the resin (i) and alkoxy-functional organosiloxane compound (ii) and endcapper (iii) and alkenyl-functional polyorganosiloxane (iv) are premixed to homogeneity, at which point the hydrosilylation catalyst (v) is added and the product is mixed again to homogeneity wherein the catalyst (v) begins to catalyze the reaction of the resin (i) and endcapper (iii). The temperature is raised to temperature sufficient to achieve reaction of the resin (i) and endcapper (iii), such as to between <NUM> and <NUM>, such as <NUM>. At this point, the product was stripped at full vacuum at a temperature sufficient to remove any excess endcapper (iii), such as at <NUM> for <NUM> minutes.

These examples are intended to illustrate the invention to one of ordinary skill in the art and should not be interpreted as limiting the scope of the invention set forth in the claims. The following components were used in the examples described below.

NMR: Solution-state <NUM>Si- and <NUM>C-NMR spectra were recorded on a Mercury VX <NUM> spectrometer at room temperature (<NUM>-<NUM>) using CDCl3 (Isotec) in a <NUM> Si-free probe. Cr(acac)<NUM> (Chromium acetylacetonoate) (<NUM>) was added to NMR samples as a relaxation agent. <NUM>Si NMR spectra were acquired at <NUM> and processed with <NUM> of Lorentzian line broadening. The spectra were only semiquantitative due to the long relaxation times of the <NUM>Si nucleus, but relative comparison of spectra acquired under identical conditions was considered quantitative. <NUM>C NMR spectra were acquired at <NUM> and processed with <NUM> of Lorentzian line broadening. For both nuclei, <NUM>-<NUM> scans with a <NUM>° pulse width were typically co-added to achieve adequate sensitivity; a <NUM>-second (<NUM>Si) or <NUM>-second (13C) delay between pulses was used. Gated decoupling was used to remove negative nuclear Overhauser effects. Chemical shifts were referenced to external tetramethylsilane (TMS).

Alclad™ Aluminum Type AD Q-Panel 2024T3: available from Q-Lab Corporation, <NUM> Canterbury Rd. , Cleveland, OH <NUM> USA;.

All blending described below was done with a Pneumatic High Shear Mixer fed with a Pneumatic pail pump and metered with a Zenith <NUM> CC/Rev Gear Pump. Catalyst feed was carried out by an Isco 500D Syringe pump.

All extrusion experiments were performed on a modular <NUM> Co-Rotating, Fully Intermeshing Twin Screw Extruder manufactured by Century. The extruder is powered by a 15HP AC motor capable of generating screw speeds of up to <NUM> rpm. The actual diameter of each screw is <NUM> and the channel depth is <NUM>. The free space cross sectional area <NUM> is <NUM>. The overall length to diameter ratio of the machine is <NUM>:<NUM>/D (<NUM> barrels) <NUM> having a total free processing volume of <NUM>. The screw elements that were utilized consisted of right and left handed conveying screws and kneading blocks.

The alkoxylated resin polymer blend (ARPB) was made by one of <NUM> methods, <NUM>) separate discrete additions of the alkoxylating agent followed by the monohydrido silicone endcapping agent (i.e., the endcapper) to a resin polymer blend (RPB), or the more preferred all-in-one consecutive addition of the alkoxylating agent and endcapping agent to a RPB.

Sample A was prepared by first mixing components <NUM> and <NUM> (see Table <NUM> below) for <NUM> minutes. The reaction was catalyzed by the addition of component <NUM>. Components <NUM>-<NUM> were then allowed to react at <NUM> for <NUM> minutes, at which point component <NUM> was added and the mixture was allowed to co continue to react at a maximum of <NUM> for <NUM> minutes. At this point, the product was stripped at full vacuum at <NUM> for <NUM> minutes.

Samples B, C & D were prepared by mixing components <NUM>, <NUM>, and <NUM> well for <NUM> minutes and then adding component <NUM> and mixing the product for <NUM> minutes. The product was then heated for <NUM> minutes at <NUM>. The temperature was then increased to <NUM> and held for <NUM> minutes. At this point, the product was stripped at full vacuum at <NUM> for <NUM> minutes. The compositions of Samples A-D are summarized in Table <NUM>:.

The alkoxylated resin polymer blends (Samples A-D) were then mixed with a non-reactive masterbatch of silicone fluid and filler (MB2030) to simulate the viscosity of the intended adhesive application. The respective viscosities of the resultant adhesive compositions were measured on a Brookfield viscometer (HAT) with a #<NUM> spindle.

To measure the viscosities, the spindles were inserted to the correct level with the adhesive sample. The spindle was then rotated at <NUM> revolutions per minute (rpm) for <NUM> minute, followed by rotation at <NUM> rpm for <NUM> minute, followed by rotation at <NUM> rpm for two minutes, wherein the adhesive samples were read for viscosity. The samples were then rotated at <NUM> rpm and read for viscosity at <NUM> minutes. The thixotropy ratio was determined by dividing the viscosity reading at the <NUM> rpm value by the reading at the <NUM> rpm value. The results are summarized in Table <NUM>:.

The results of Table <NUM> confirm that adhesive compositions prepared from alkoxy-functional siloxane reactive resins made by either sequential addition or by an all in one type addition (Comparative Samples AA and BB) exhibited similar viscosity profiles.

Further, the reduction in the amount of alkoxylating agent in the alkoxylated resin polymer blend while increasing the amount of endcapper (Comparing Samples CC and DD to BB), while maintaining the overall SiH/Vi ratio in the APRB, resulted in a slight decrease in the viscosity of the adhesive compositions to which they are introduced and a corresponding reduction in the thixotropy index.

In a <NUM> liter Turello mixer <NUM> of a silicone polymer masterbatch (MB2030) (SFD-<NUM>/silica blend), <NUM> of SFD120 polymer, <NUM> of OS20 silicone fluid (methylsiloxane fluid available from Dow Corning Corporation of Midland, MI) and <NUM> of OFS-<NUM> isomer reducing agent were loaded. The mixture was inerted using <NUM>% oxygen in nitrogen atmosphere and stirred for <NUM> minutes. To this homogenized mixture was added <NUM> of BHT, <NUM> of cyclic methylhydrogensiloxane, and <NUM> of AMA. The resultant mixture was stirred for an additional <NUM> minutes at room temperature, at which point <NUM> of a platinum catalyst was added and the mixtture. The mixture was stirred for <NUM> additional minutes before setting the temperature at <NUM>. The temperature was held for <NUM> minutes at <NUM> before cooling to greater than <NUM> and adding <NUM> of DAM. The mixture was then cooled to less than <NUM> before adding <NUM> of methyltrimethoxysilane (MTM). The mixture was then heated to <NUM> and held for <NUM> minutes, wherein the temperature was increased to <NUM> and a vacuum of <NUM> Hg was applied for <NUM> minutes. The resultant polymer is hereinafter referred to as MCP-<NUM>.

To form the polymer MCP, the same procedure as the previous paragraph was followed, with the exception of the addition of the isomer reducing agent.

Resin polymer blends (RPB HS and RPB LS) in examples below were prepared by the slow addition of <NUM> parts of Dow Corning® SFD-<NUM> polymer (with stirring) to <NUM> parts of a vinyl MQ resin (either ViMQ Resin <NUM> or ViMQ Resin <NUM>) in xylene. The homogeneous solution was devolatized at <NUM> under a <NUM> Hg vacuum on a rotary evaporator to form the respective resin polymer blend (RPB HS, made ViMQ Resin <NUM>; or RPB LS, made ViMQ Resin <NUM>).

Next, <NUM> grams of RPB HS or LS were blended into a <NUM>/<NUM> quart Ross mixer with <NUM> grams of Component <NUM> and <NUM> grams of Component <NUM>. <NUM> grams of Component <NUM> and <NUM> grams of Component <NUM> were optionally added to this mixture and mixed for <NUM> minutes. The treating blend of Components <NUM> and <NUM> were then added to the mixture, and the mixture was blended for <NUM> minutes and then heated to <NUM> for <NUM> minutes. Finally, the heat was increased to <NUM> and the mixture was placed under vacuum. The resultant compositions, shown in Table <NUM>, were labeled ARPB-E, ARPB-F, and ARPB-G, respectively.

In a <NUM> quart Ross mixer, the following components were mixed with cooling to maintain a temperature of <NUM> or less to form adhesive compositions, as shown in Table <NUM>.

Next, the viscosity of the adhesives formed from Table <NUM>, and listed below in Table <NUM>, were monitored at <NUM> shear rates (<NUM> and <NUM> sec-<NUM>) using an Ares parallel plate rheometer (Ares Rheometer model G2 from TA instruments, <NUM> Lukens Drive, New Castle, DE <NUM>) as a function of days aged at room temperature. The results are summarized in Tables <NUM> and <NUM>:.

As Tables <NUM> and <NUM> confirm, the low silanol versions of ARPB (ARPB-E and F) provided reduced viscosity as compared with the higher silanol version of ARPB (ARPB-G).

Next the adhesives were applied to Alclad™ aluminum substrates (available from Alcoa) and cured for <NUM> minutes at <NUM> and having <NUM> mil (<NUM> mil equals <NUM> millimeter) bond line thickness. One half of the samples were evaluated at room temperature and aged, while the remaining samples were placed in a pressure cooker tester (PCT) for <NUM> hours at <NUM> additional atmosphere and evaluated after aging. The lap shear adhesive properties of the coated substrates appropriately aged were evaluated for peak stress, in pounds per square inch (PSI), with the results summarized in Table <NUM> (<NUM> PSI = <NUM> kPa).

As Table <NUM> confirms, the introduction of an isomer reducing agent to the adhesive composition resulted in comparable adhesion to Alclad™ aluminum substrates as compared with samples that did not include the isomer reducing agent.

Next, the dispensing properties of various thermal radical cure compositions were evaluated.

The materials in Table <NUM> were cold blended in a Hauschild Speedmixer DAC <NUM> FV-K available from FlackTek Inc, Landrum, SC <NUM> USA.

The components in Table <NUM> were also mixed in the speedmixer prior to evaluation for dispensability.

Dispense and stringing checks were done using an EFD <NUM>-XL syringe dispenser (Available from Nordson EFD, East Providence, RI <NUM> USA. Materials being compared were dispensed from <NUM> EFD syringes at <NUM> pounds per square inch (<NUM> PSI = <NUM> kPa) of air pressure.

The rating is a subjective rating based on the ability to control the adhesive bead at an applied pressure. The rating is a reflection of the tendency and length of any bead on termination of applied pressure. Even with superior cure and adhesion to multiple substrates, the inability to routinely dispense a bead or dot of adhesive on a substrate, in a timely manner, can stop commercial adoption.

As Table <NUM> confirms, the ARPB-<NUM> defined above improves dispensing without loss of mechanical properties. It also provides a secondary cure mechanism by which any surface tack in the radical cured system due to oxygen inhibition can be overcome. It should also be noted that the alkoxy functionality is highly desirable for adhesion to mineral and metallic surfaces.

<NUM>" x <NUM>" panels of the various substrates were cleaned with acetone (<NUM> samples prepared). Bondlines were established using Spheriglass spacer beads (Potters Industries Inc. <NUM> North Baker Drive, Canby, OR <NUM>-<NUM>) appropriate with the application (i.e., <NUM> mil (<NUM> micron)). Larger bond lines used <NUM> mil wire.

A <NUM>/<NUM>" binder clip was used with both spacers methods to secure substrates during cure. Cure at time and temperature were specified in results below. Testing was carried out on Instron <NUM> tensiometer at <NUM> inches (<NUM>) per minute (Instron Worldwide Headquarters, <NUM> University Ave. , Norwood, MA <NUM>-<NUM>).

Claim 1:
An alkoxy-functional organopolysiloxane resin and polymer comprising a reaction product of a reaction comprising:
(i) an alkenyl-functional siloxane resin comprising R<NUM>SiO<NUM>/<NUM> units and SiO<NUM>/<NUM> units,
wherein each R is independently a monovalent hydrocarbon radical having <NUM> to <NUM> carbon atoms with the proviso that at least one R is an alkenyl radical,
wherein the molar ratio of the R<NUM>SiO<NUM>/<NUM> units to SiO<NUM>/<NUM> units has a value ranging from <NUM>/<NUM> to <NUM>/<NUM>,
(ii) an alkoxysilane-functional organosiloxane compound having at least one silicon-bonded hydrogen atom at a molecular terminal;
(iii) an endcapper according to the formula to the formula R<NUM><NUM>SiO-(R<NUM><NUM>SiO)s-SiR<NUM><NUM>H or R<NUM><NUM>SiO-(R<NUM><NUM>SiO)t-(HR<NUM>SiO)-SiR<NUM><NUM>, or combinations thereof, wherein each R<NUM> is independently a hydrocarbon radical and wherein the subscripts s and t have respective values ranging from <NUM> to <NUM>; and
(iv) a polyorganosiloxane having an average, per molecule, of at least <NUM> aliphatically unsaturated organic groups;
in the presence of a (v) hydrosilylation catalyst.