Method for preparing a laminate comprising a silicone pressure sensitive adhesive bonded to a fluorosilicone rubber or silicone foam

Abstract

The laminate comprises a silicone pressure sensitive adhesive adhered to an article comprising a fluorosilicone rubber or a silicone foam.A method of making the laminate is provided.

Description

[Technical field]

[0001] CROSS-REFERENCE TO RELATED APPLICATIONS This application claims the benefit under 35 U.S.C. §119(e) of U.S. Provisional Patent Application No. 63 / 317,126, filed March 7, 2022, and U.S. Provisional Patent Application No. 63 / 335,735, filed April 28, 2022. U.S. Provisional Patent Application Nos. 63,317,126 and 63 / 335,735 are incorporated herein by reference.

[0002] The present invention relates to a method for preparing a silicone pressure sensitive adhesive composition that can be cured to form a silicone pressure sensitive adhesive having strong adhesion to substrates where conventional silicone pressure sensitive adhesives typically exhibit poor adhesion. More specifically, the present invention relates to a method for preparing a peroxide curable silicone pressure sensitive adhesive composition that can be cured to form a silicone pressure sensitive adhesive having strong adhesion to fluorosilicone rubber or silicone foam. The laminate comprises a silicone pressure sensitive adhesive adhered to a substrate comprising a fluorosilicone rubber article or a silicone foam article.

[0003] Introduction Currently available silicone pressure sensitive adhesives can suffer from the drawback of having relatively poor adhesive strength to fluorosilicone rubber articles and silicone foam articles, which often prevents them from meeting the needs of applications in which they are used to adhere to these articles, such as electronics, automotive, and masking tape applications. Summary of the Invention

[0004] A method of making a laminate comprising an article selected from the group consisting of a fluorosilicone rubber article and a silicone foam article is provided, the method comprising: (a) under conditions for carrying out a condensation reaction; (P) a bis-hydroxyl terminated polydiorganosiloxane having a weight average molecular weight of from 10,000 g / mol to less than 200,000 g / mol as measured by GPC; (R) a hydroxyl-functional polyorganosilicate resin having a weight average molecular weight of 4,000 g / mol to <10,000 g / mol as measured by GPC; and (S) a solvent, wherein starting materials (P) and (R) are present in a weight ratio (R) / (P) of from 0.76 / 1 to less than 2.15 / 1 to form a reaction mixture; (b) adding (C) a condensation reaction catalyst to the reaction mixture to form a catalyzed reaction mixture; (c) heating the catalyzed reaction mixture at a temperature >RT to 145°C to remove water, thereby forming a silicone pressure sensitive adhesive composition; (d) coating a surface of a backing substrate with a silicone pressure sensitive adhesive composition; (e) drying the silicone pressure sensitive adhesive composition; and (f) curing the silicone pressure sensitive adhesive composition to form a silicone pressure sensitive adhesive layer having a surface adhered to a surface of a backing substrate, the silicone pressure sensitive adhesive layer further comprising an opposing surface opposite the surface of the backing substrate; (g) adhering an opposing surface of the silicone pressure sensitive adhesive to a surface of an article selected from the group consisting of a fluorosilicone rubber article and a silicone foam article. [Brief description of the drawings]

[0005] [Figure 1] A partial cross-sectional view of a laminate article 100 is shown. [Diagram 2] A partial cross-sectional view of a laminate article 200 is shown.

[0006] Explanation of symbols 100 Partial cross section of laminated article 101 Backing material 101b Surface of backing substrate 101 102 Silicone pressure sensitive adhesive 102a Surface of silicone pressure sensitive adhesive 102 102b: the opposite surface of the silicone pressure sensitive adhesive 102 103 Fluorosilicone rubber articles 103a Surface of fluorosilicone rubber article 103 200 Partial cross section of laminated article 201 Backing material containing silicone rubber 201b Surface of the backing substrate 201 202 Silicone pressure sensitive adhesives 202a Surface of silicone pressure sensitive adhesive 202 202b: the opposite surface of the silicone pressure sensitive adhesive 202 DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0007] The method for producing the laminate is as follows: (1) under conditions for carrying out a condensation reaction, (P) a bis-hydroxyl terminated polydiorganosiloxane having a weight average molecular weight of 10,000 g / mol to <200,000 g / mol as measured by GPC; (R) a hydroxyl-functional polyorganosilicate resin having a weight average molecular weight of 4,000 g / mol to <10,000 g / mol as measured by GPC; (S) solvent, and Optionally, a starting material comprising (N) a neutralizing agent, combining starting materials (R) and (P) and *** to form a reaction mixture, wherein the starting materials are present in a weight ratio (R) / (P) of 0.76 / 1 to 2.15 / 1; (2) adding (C) a condensation reaction catalyst to the reaction mixture to form a catalyzed reaction mixture; (3) heating the catalyst reaction mixture at a temperature between room temperature and 145° C. to remove water; Optionally, (4) recovering the condensation reaction product of (P) and (R); and optionally, (5) adding up to 4 weight percent, based on the combined weight of (R) and (P), of (X) a peroxide crosslinker to form a silicone pressure sensitive adhesive composition; Optionally, (6) treating the surface of the backing substrate; and (7) coating a surface of a backing substrate with a silicone pressure sensitive adhesive composition; (8) drying the silicone pressure sensitive adhesive composition; and (9) curing the silicone pressure sensitive adhesive composition to form a silicone pressure sensitive adhesive layer having a surface adhered to a surface of a backing substrate, the silicone pressure sensitive adhesive layer further including an opposing surface opposite the surface of the backing substrate; Optionally, (10) treating a surface of an article selected from the group consisting of a fluorosilicone rubber article and a silicone foam article; (11) adhering an opposing surface of the silicone pressure sensitive adhesive to a surface of an article; and Includes.

[0008] Step (1) of the above process may be carried out by any convenient means, such as by mixing the starting materials, including (P), (R), (S), and optionally (N), introduced above and described in detail below, in a batch reactor, optionally equipped with a stirrer and jacket. The condensation reaction may be carried out at a temperature between 20° C. and 150° C., or from RT to the reflux temperature of the starting material (S), the solvent. The reaction time depends on various factors, including the selection of starting materials and the temperature, but the condensation reaction in step (1) may be carried out for, for example, 0.5 hours to 20 hours, or 1 hour to 10 hours. The condensation reaction may be carried out, for example, as described in U.S. Pat. No. 5,916,981 to Cifuentes et al., by changing the appropriate starting materials to those described below.

[0009] (P) Bis-hydroxyl terminated polydiorganosiloxane The starting material (P) is the bis-hydroxyl terminated polydiorganosiloxane (polymer) used in step (1). This polymer has the following formula: [ka] (In the formula, each R 1 R may have an independently selected alkyl group of 1 to 6 carbon atoms, and the subscript a represents the average number of difunctional siloxane units per molecule, where 250≦a≦3000, or alternatively 270≦a≦2000. Alternatively, the subscript a may be at least 250, alternatively at least 270, alternatively at least 300, alternatively at least 350, alternatively at least 400, alternatively at least 450, or alternatively at least 500, while the subscript a may be up to 3,000, alternatively up to 2,500, alternatively up to 2,000, alternatively up to 1,500, alternatively up to 1,100, or alternatively up to 1,000. 1 Examples of alkyl groups include methyl, ethyl, propyl (including n-propyl and isopropyl), butyl (including n-butyl, tert-butyl, sec-butyl, and isobutyl), pentyl (including n-pentyl, cyclopentyl, and branched isomers having 5 carbon atoms), and hexyl (including n-hexyl, cyclohexyl, and branched isomers having 6 carbon atoms). 1 may be methyl or ethyl, or may be methyl.

[0010] Suitable polymers for the starting material (P) are known in the art and are commercially available from a variety of sources, such as Gelest Inc. (Morrisville, Pennsylvania, USA) and DSC. Examples of suitable polymers include bishydroxyl-terminated polydimethylsiloxanes having Mw of 20,000 g / mol to 150,000 g / mol, alternatively 40,000 g / mol to 135,000 g / mol, alternatively 75,000 g / mol to 135,000 g / mol; and alternatively 100,000 g / mol to 140,000 g / mol, where Mw can be measured by GPC.

[0011] The amount of polymer may be sufficient to provide from 32% to 56% by weight, alternatively from 37% to 52% by weight, alternatively from 42% to 47% by weight, based on the combined weight of the starting materials (P) polymer, (R) resin, (N) neutralizing agent, and (C) condensation reaction catalyst.

[0012] (R) Polyorganosilicate resin The starting material (R) is the hydroxyl-functional polyorganosilicate resin (resin) used in step (1). The resin has the formula R 1 3SiO 1 / 2 and a monofunctional unit of formula SiO 4 / 2 wherein R 1 is as above). Alternatively, the monofunctional unit may be of the formula (MeSiO 1 / 2 The polyorganosilicate resin is soluble in solvents such as those described below as starting materials (S), exemplified by aliphatic and / or aromatic hydrocarbons such as benzene, toluene, xylene, ethylbenzene, heptane, and combinations thereof.

[0013] When prepared, the resin contains the monofunctional and tetrafunctional units described above, the resin further contains units having silicon-bonded hydroxyl groups and has the formula Si(OSiR 1 3)4 (in the formula, R 1 The polyorganosilicate resin may include a neopentamer of the formula (I) (wherein m is as defined above), for example, the neopentamer may be tetrakis(trimethylsiloxy)silane. The concentration of silanol groups present in the resin may be determined using FTIR spectroscopy according to ASTM standard E-168-16. The molar ratio of mono- to tetrafunctional units, excluding mono- and tetrafunctional units from the neopentamer, is expressed as {M(resin)} / {Q(resin)}, or M:Q. The M:Q ratio represents the molar ratio of the total number of triorganosiloxy groups (monofunctional units) in the resinous portion of the polyorganosilicate resin to the total number of silicate groups (Q units) in the resinous portion. The M:Q ratio may be from 0.5:1 to 1.5:1.

[0014] The Mn of the polyorganosilicate resin is determined by the R 1 The Mn of the polyorganosilicate resin refers to the number average molecular weight measured using GPC when the peak representing the neopentamer is excluded from the measurement. The Mn of the polyorganosilicate resin may be 2,000 to 3,500 g / mol. The Mw of the polyorganosilicate resin refers to the weight average molecular weight measured using GPC. The Mw of the polyorganosilicate resin may be at least 4000 g / mol, alternatively at least 5000 g / mol, alternatively at least 5500 g / mol, while the Mw may be <10,000 g / mol, alternatively up to 9000 g / mol, alternatively up to 8500 g / mol. Alternatively, the Mw of the polyorganosilicate resin may be from 4,000 g / mol to <10,000 g / mol, alternatively from 5000 g / mol to 9000 g / mol, alternatively from 5,500 g / mol to 8500 g / mol.

[0015] The polyorganosilicate resins can be prepared by any suitable method, such as cohydrolysis of the corresponding silanes or by silica hydrosol capping methods. The polyorganosilicate resins can be prepared by silica hydrosol capping methods, such as those disclosed in U.S. Patent No. 2,676,182 to Daudt et al., U.S. Patent No. 4,611,042 to Rivers-Farrell et al., and U.S. Patent No. 4,774,310 to Butler et al. The above-mentioned method of Daudt et al. involves reacting a silica hydrosol with a hydrolyzable triorganosilane, such as trimethylchlorosilane, a siloxane, such as hexamethyldisiloxane, or a mixture thereof, under acidic conditions, and recovering a copolymer having monofunctional units and Q units. The resulting copolymer generally contains 2 to 5 weight percent hydroxyl groups.

[0016] The intermediates used to prepare the polyorganosilicate resins can be triorganosilanes and silanes or alkali metal silicates containing four hydrolyzable substituents. The triorganosilanes are represented by the formula R 1 3SiX 1 (In the formula, R 1 is as above, and X 1 represents a hydrolyzable substituent such as hydroxyl. A silane having four hydrolyzable substituents can have the formula SiX 2 4, wherein each X 2 is halogen, alkoxy, or hydroxyl. Suitable alkali metal silicates include sodium silicate.

[0017] The resin selected for the starting material (R) has the unit formula (R 1 3SiO 1 / 2 ) b (SiO 4 / 2 ) c (HO 1 / 2 ) d (In the formula, each R 1 are independently selected alkyl groups of 1 to 6 carbon atoms as described above, subscripts b and c represent the mole fractions of monofunctional and tetrafunctional units, respectively, with subscripts b and c having values ​​such that 0.4≦b≦0.5, 0.5≦c≦0.6, and the amount (b+c)=1, subscript d represents the amount of hydroxyl groups in the resin, with subscript d having a value sufficient to provide the resin with a hydroxyl content of 2% to 5% by weight, and Mw is as described above. Suitable resins are known in the art and are commercially available, for example, from DSC. The amount of resin may be sufficient to provide 43% to 68% by weight, alternatively 48% to 63% by weight, and 53% to 58% by weight of resin, based on the combined weight of the starting materials (P), (R), (N), and (C).

[0018] The resin (R) and polymer (P) are present in a weight ratio (R) / (P) of 0.76 / 1 to less than 2.15 / 1. Alternatively, (R) / (P) may be 0.93 / 1 to 1.40 / 1, alternatively 1.14 / 1 to 1.40 / 1. Alternatively, (R) / (P) may be at least 0.76 / 1, alternatively at least 0.93 / 1, alternatively at least 1.14 / 1, while (R) / (P) may be up to 2.15 / 1, alternatively up to 1.72 / 1, alternatively up to 1.40 / 1. Without wishing to be bound by theory, it is believed that (R) / (P) less than 0.76 / 1 or greater than 2.15 / 1 may result in a silicone pressure sensitive adhesive with insufficient adhesion to fluorosilicone rubber or silicone foam, or both.

[0019] (S) Solvent The starting material (S) is a solvent. To facilitate the introduction of certain starting materials, such as (R) resin, a solvent may be added during step (1) and optionally subsequent steps, such as step (2). Solvents that can be used herein are those that aid in fluidizing the starting materials but do not essentially react with the starting materials. The solvent may be selected based on the solubility of the starting materials and the volatility of the solvent. Solubility refers to the solvent being sufficient to dissolve and / or disperse the starting materials. Volatility refers to the vapor pressure of the solvent. Without being bound by theory, it is believed that if the solvent is too volatile (has too high a vapor pressure), the solvent may evaporate too quickly from the reaction mixture during step (3). However, if the solvent is not volatile enough (has too low a vapor pressure), too much solvent may remain in the condensation reaction product prepared in step (3) and / or water produced as a by-product of the condensation reaction may not be sufficiently removed during step (3) and, if present, step (4).

[0020] Suitable solvents include polyorganosiloxanes having suitable vapor pressures, such as hexamethyldisiloxane, octamethyltrisiloxane, hexamethylcyclotrisiloxane, and other low molecular weight polyorganosiloxanes, such as DOWSIL™ 200 Fluids and DOWSIL™ OS FLUIDS, 0.5-1.5 cSt, available from DSC.

[0021] Alternatively, the solvent may comprise an organic solvent. The organic solvent may be a ketone such as acetone, methyl ethyl ketone, or methyl isobutyl ketone; an aromatic hydrocarbon such as benzene, toluene, ethylbenzene, or xylene; an aliphatic hydrocarbon such as heptane, hexane, or octane; a glycol ether such as propylene glycol methyl ether, dipropylene glycol methyl ether, propylene glycol n-butyl ether, propylene glycol n-propyl ether, or ethylene glycol n-butyl ether, a halogenated hydrocarbon, for example, dichloromethane, 1,1,1-trichloroethane, or methylene chloride; chloroform; dimethyl sulfoxide; dimethylformamide, acetonitrile; tetrahydrofuran, white spirit; mineral spirit, naphtha, n-methylpyrrolidone; or a combination thereof.

[0022] The amount of solvent depends on various factors, such as the type of solvent selected and the amount and type of other starting materials selected for use in the method. However, the amount of solvent may range from 1% to 99%, alternatively 2% to 90%, based on the weight of all starting materials in step (1). All or a portion of the solvent may be optionally removed during and / or after step (3). For example, water may be formed as a by-product of the condensation reaction in steps (2) and (3). To drive the reaction forward, some or all of the water may be removed, for example, by azeotropic distillation with the solvent.

[0023] (N) Neutralizer The starting material (N), the neutralizing agent, is optional. The neutralizing agent may include silyl phosphate. Without being bound by theory, it is believed that the neutralizing agent may be added to scavenge impurities in the above-mentioned (R) resin and / or (P) polymer before the condensation reaction. The neutralizing agent may be, for example, silyl phosphate. Silyl phosphates, such as bis(trimethylsilyl) hydrogen phosphate, are commercially available from DSC.

[0024] The amount of neutralizing agent will depend on a variety of factors, including the type of (P) polymer and (R) resin selected, but can be from 0.005% to 0.02%, alternatively from 0.01% to 0.015%, based on the combined weight of the starting materials (P), (R), (N) and (C).

[0025] (C) Condensation reaction catalyst The starting material (C) added in step (2) is a condensation reaction catalyst capable of catalyzing the condensation reaction of the hydroxyl groups of the above-mentioned (P) polymer and (R) resin. The condensation reaction catalyst is not particularly limited and may include an acid or a base condensation reaction catalyst. For example, suitable base catalysts include metal hydroxides such as lithium hydroxide, sodium hydroxide, potassium hydroxide, and calcium hydroxide, carbonates such as sodium carbonate and potassium carbonate, bicarbonates such as sodium bicarbonate and potassium bicarbonate, metal alkoxides such as sodium methoxide and potassium butoxide, organometallic compounds such as butyl lithium, potassium silanolate, ammonia gas, aqueous ammonia, nitrogen compounds such as methylamine, trimethylamine, and triethylamine, and the like. Alternatively, the condensation reaction catalyst may be an acid, for example, organic acids such as acetic acid, benzoic acid, octanoic acid, and citric acid, and mineral acids such as hydrochloric acid, sulfuric acid, and phosphoric acid are suitable. Alternatively, the condensation reaction catalyst may be an acid catalyst, for example, an organic acid such as benzoic acid.

[0026] Suitable condensation reaction solvents are commercially available from a variety of sources, including Sigma Aldrich, Inc. (St. Louis, Missouri, USA) and Acros. The amount of catalyst will depend on a variety of factors, including the type of catalyst selected and the temperature of step (1), but may be from 0.1% to 0.5%, alternatively from 0.25% to 0.3%, based on the combined weight of the starting materials (P), (R), (C) and (N).

[0027] Step (4) in the above method is optional. After the condensation reaction product of the (P) polymer and the (R) resin is formed, the condensation reaction product may further include unreacted starting materials, solvent, and water as a by-product. In step (4), the condensation reaction product may be recovered, for example, by removing the solvent, water, and unreacted starting materials, for example, by distillation and / or stripping, optionally with heating and / or under reduced pressure.

[0028] Step (5) in the above method is optional. The reaction product after step (3) or step (4), if present, can be used to form a silicone pressure-sensitive adhesive composition. Alternatively, (X) a peroxide crosslinker can be added in step (5) to form a silicone pressure-sensitive adhesive composition that can cure faster than if the peroxide crosslinker is not present, as long as other conditions, such as temperature, are kept constant.

[0029] (X) Peroxide crosslinking agent The starting material (X) added when step (5) is present is a peroxide crosslinker. The peroxide crosslinking agent may be an organic peroxide or hydroperoxide, such as benzoyl peroxide; 4-monochlorobenzoyl peroxide; t-butyl peroctoate; t-butyl peroxybenzoate, tert-butyl peroxybenzoate, tert-butylcumyl peroxide, tert-butyl oxide 2,5-dimethyl-2,5-di-tert-butylperoxyhexane; 2,4-dichlorobenzoyl peroxide; di-tertbutylperoxy-diisopropylbenzene; 1,1-bis(tert-butylperoxy)-3,3,5-trimethylcyclohexane; 2,5-di-tert-butylperoxyhexane-3,2,5-dimethyl-2,5-bis(tert-butylperoxy)hexane; cumyl-tert-butyl peroxide; dicumyl peroxide; di-t-butyl peroxide; t-butyl hydroperoxide; cumene hydroperoxide; di-t-amyl peroxide, and combinations of two or more thereof. Furthermore, the diperoxide crosslinking agent may be used alone or in combination with other diperoxide crosslinking agents. Such diperoxide crosslinking agents include, but are not limited to, 1,4-bis-(t-butylperoxycarbo)cyclohexane; 1,2-di(t-butylperoxy)cyclohexane, and 2,5-di(t-butylperoxy)-3-hexyne. Peroxide crosslinking agents suitable for use as starting material (X) are known in the art and are commercially available from various sources, such as Sigma-Aldrich, Inc. (St. Louis, Missouri, USA).

[0030] Starting material (X) may include one peroxide crosslinker or may include a combination of two or more peroxide crosslinkers. The amount of starting material (X) added in step (5) will depend on various factors, including the type and amount of peroxide crosslinker selected and the selection of the (P) polymer and (R) resin, but the amount of peroxide crosslinker, if present, may be from 0.1% to 4% by weight, alternatively from 1% to 4% by weight, alternatively from 2% to 3% by weight, based on the combined weight of starting materials (P), (R), (C), and (S).

[0031] Step (6) in the methods described herein is optional. However, step (6) may be included in the method to improve adhesion of the silicone pressure sensitive adhesive to the backing substrate. Thus, the method of forming an adhesive article may optionally further comprise (6) treating the surface of the backing substrate prior to applying the silicone pressure sensitive adhesive composition. Treating the surface may be carried out by any convenient means, such as applying a primer or subjecting the surface to a corona discharge treatment, etching, or plasma treatment prior to applying the silicone pressure sensitive adhesive composition to the surface. Alternatively, treating the surface may comprise applying a primer to the surface of the backing substrate.

[0032] The step (7) of coating the silicone pressure-sensitive adhesive composition onto the surface of the backing substrate may be carried out by any convenient means, for example, the silicone pressure-sensitive adhesive composition may be applied by a gravure coater, a comma coater, an offset coater, an offset gravure coater, a roller coater, a reverse roller coater, an air knife coater, a slot die, or a curtain coater.

[0033] In the methods described herein, steps (7)-(9) may be carried out via wet casting or dry casting, in which the silicone pressure sensitive adhesive layer may be durably adhered to a backing substrate, such as a polymeric film and / or foam, as described below.

[0034] The backing substrate can be any material that can withstand the curing conditions used in step (9) to cure the silicone pressure sensitive adhesive composition to form a silicone pressure sensitive adhesive on the surface of the backing substrate. For example, any backing substrate that can withstand heat treatment at a temperature of 120° C. or higher, or even 150° C. or higher, is suitable. Examples of materials suitable for such backing substrates include polymeric films and / or foams, which can include polyimide (PI), polyetheretherketone (PEEK), polyethylenenaphthalate (PEN), liquid crystal polyarylate, polyamideimide (PAI), polyethersulfide (PES), polyethyleneterephthalate (PET), polycarbonate (PC), polymethylmethacrylate (PMMA), thermoplastic polyurethane (TPU), thermoplastic elastomer (TPE), polyethylene (PE), or polypropylene (PP). Alternatively, the backing substrate can be glass. Alternatively, the backing substrate can be a release liner, for example when the silicone pressure sensitive adhesive is used in a dry casting process. The thickness of the backing substrate is not critical. However, the thickness may be from 5 μm to 300 μm, alternatively from 10 μm to 200 μm. Alternatively, the backing substrate used in step (7) may be selected from the group consisting of PE, PU, ​​TPE, and TPU.

[0035] Step (8) of the method includes drying the silicone pressure sensitive adhesive composition. Drying may be accomplished by any convenient means, such as heating at a temperature and for a time sufficient to evaporate all or a portion of the solvent, but insufficient to completely cure the silicone pressure sensitive adhesive composition. For example, drying may be accomplished by heating at a temperature of from 50° C. to 120° C., alternatively from 70° C. to 100° C., alternatively from 70° C. to 80° C., for a time sufficient to remove all or a portion of the solvent (e.g., from 30 seconds to 1 hour, alternatively from 1 minute to 5 minutes).

[0036] After drying, the method further includes a step (9) of curing the silicone pressure sensitive adhesive composition to form a laminate article comprising a silicone pressure sensitive adhesive layer having a surface adhered to a surface of a backing substrate, the silicone pressure sensitive adhesive layer further comprising an opposing surface opposite the surface of the backing substrate.

[0037] Curing of the pressure sensitive adhesive composition in step (9) may be carried out by heating at a temperature of 80°C to 200°C, alternatively 90°C to 210°C, alternatively 150°C to 205°C, alternatively 180°C to 205°C for a time sufficient to cure the pressure sensitive adhesive composition (e.g., 30 seconds to 1 hour, alternatively 1 to 5 minutes). If a faster cure rate or a lower process oven temperature is required, the amount of (X) peroxide crosslinker may be increased. This results in a silicone pressure sensitive adhesive formed on the surface of the backing substrate. Curing may be carried out by placing the coated backing substrate in an oven. The amount of silicone pressure sensitive adhesive composition coated on the backing substrate will depend on the particular application, but the amount may be sufficient to provide a silicone pressure sensitive adhesive having a thickness of 5 micrometers to 100 micrometers after curing.

[0038] The methods described herein may optionally further include additional steps after step (9). The additional steps may include, for example, applying a removable release liner to the opposing surface of the silicone pressure-sensitive adhesive layer opposite the backing substrate to protect the silicone pressure-sensitive adhesive prior to use (e.g., when the backing substrate is a polymeric film and / or foam, or glass). The release liner may be applied before, during, or after curing the silicone pressure-sensitive adhesive composition, or after curing.

[0039] The silicone pressure sensitive adhesive prepared in step (9) adheres to a fluorosilicone rubber article or a silicone foam article, or both. Without being bound by theory, it is believed that the silicone pressure sensitive adhesive prepared in step (9) may have an adhesion to fluorosilicone rubber of >400 gf / in, alternatively at least 900 gf / in, alternatively at least 1,000 gf / in, while the adhesion may be up to 1,100 gf / in, alternatively up to 1,000 gf / in, alternatively up to 950 gf / in, when tested according to the peel adhesion test method described in the Examples section below. Without being bound by theory, it is believed that the silicone pressure sensitive adhesive prepared in step (9) may have an adhesion to silicone foam of >300 gf / in, alternatively >350 gf / in, alternatively >375 gf / in, while the adhesion may be up to 550 gf / in, alternatively up to 510 gf / in, alternatively up to 475 gf / in, when tested according to the Peel Adhesion Test Method described in the Examples below.

[0040] Although treatment of the article is not required for this adhesion, the method may optionally further include a step (10) of treating the surface of the article, which may promote and / or improve adhesion of the silicone pressure sensitive adhesive to the surface of the article. Treating the surface of the article may be carried out by any convenient means, such as, for example, cleaning the surface of the article with an alcohol, such as isopropanol, or any of the surface treatments described above in step (6).

[0041] The article may include a fluorosilicone rubber or a silicone foam. The fluorosilicone rubber article is not particularly limited. The fluorosilicone rubber article may have a durometer Shore A of 30 to 60, as measured by ASTM D2240. Fluorosilicone rubber (F-LSR) is known in the art and may be made by known methods, such as those disclosed in U.S. Pat. No. 4,857,564 to Maxson, U.S. Pat. No. 4,882,368 to Koch et al., U.S. Pat. No. 5,171,773 to Koch et al., U.S. Pat. No. 5,824,736 to Koch et al., and JP 2017-0267829 to Drake et al. Alternatively, the fluorosilicone rubber article may be selected based on the desired end use of the laminate prepared herein. Exemplary fluorosilicone rubber (F-LSR) are known in the art and are commercially available. For example, F-LSR includes SILASTIC™ brand F-LSR available from DSC. These include SILASTIC™ FL 30-9201, SILASTIC™ FL 40-9201, and SILASTIC™ FL 60-9201, which are fluorosilicone liquid silicone rubbers having a durometer Shore A value of 30-60.

[0042] Alternatively, the article may include a silicone foam. The silicone foam may have a durometer Shore 00 value of 10 to 70. The silicone foam may have a hardness of 0.03 g / cm 3 ~1.5g / cm 3The silicone foam may have a density of 100-150 psi. The silicone foam may have a compression of 1-100 psi. The silicone foam may have a tensile strength of 1-300 psi. Silicone foams, such as open-cell silicone foams, are known in the art and are commercially available. For example, articles containing silicone foams are available from McMaster-Carr (Elmhurst, Illinois, USA). These include McMaster-Carr product names 1652N101-129, 5025T171-176, 181-186, and 191-196, and 87485K212-216, 221-226, and 231-236. Silicone foams may be prepared by known methods, such as those disclosed in Bauman et al., U.S. Pat. No. 5,252,627, Koch et al., U.S. Pat. No. 5,330724, Koch et al., U.S. Pat. No. 5,683,527, and Chung et al., U.S. Pat. No. 5,744,507.

[0043] The method described herein further comprises step (11) of adhering the counter surface of the silicone pressure sensitive adhesive described in step (9) to a surface of an article. Step (11) may be carried out by any convenient means, such as contacting the surface of the article with the counter surface of the silicone pressure sensitive adhesive and applying pressure. If a release liner is used to protect the counter surface of the silicone pressure sensitive adhesive, the release liner is removed prior to contacting the surface of the silicone rubber article with the counter surface of the silicone pressure sensitive adhesive. The resulting product prepared in step (11) is a laminate.

[0044] Alternatively, when dry casting is used in steps (7)-(9) above, the backing substrate includes a release liner. The release liner may be removed after step (9) to form the silicone pressure sensitive adhesive layer as a free-standing film. Alternatively, the release liner may be removed after step (11). When dry casting is performed, the method includes: Optionally, (12) treating a surface of a second article (i.e., a second fluorosilicone rubber article or a second silicone foam article); and (13) adhering the surface of the silicone pressure sensitive adhesive layer (exposed by removal of the release liner) to the surface of a second silicone rubber article.

[0045] The second article comprises a fluorosilicone rubber or a silicone foam, as described above for use in step (11). The second article may be the same as the article used in step (11). Alternatively, the second article may be different from the article used in step (11). In this case, the laminated article formed by the method has a silicone pressure sensitive adhesive layer sandwiched between the above-mentioned article and the second article.

[0046] FIG. 1 shows a partial cross-section of a laminate (100) prepared by the method described above. The laminate (100) comprises a silicone pressure sensitive adhesive (102) having a surface (102a) and an opposing surface (102b). The opposing surface (102b) of the silicone pressure sensitive adhesive (102) adheres to a surface (103a) of a fluorosilicone rubber article (103) with a peel adhesion of 400 gf / in as measured by the test method described in the Examples below. The silicone pressure sensitive agent (102) may have a thickness of 10 μm to 200 μm. The silicone pressure sensitive adhesive (102) adheres to a backing substrate (101) having a surface (101b). The surface (102a) of the silicone pressure sensitive adhesive (102) is in contact with the surface (101b) of the backing substrate (101). The backing substrate (101) may be selected from the group consisting of PE, PU, ​​TPU, and TPE and may have a thickness of 10 μm to 200 μm. The fluorosilicone rubber article (103) may be SILASTIC™ F-LSR as described above.

[0047] The silicone pressure sensitive adhesive composition may be used in the fabrication of the laminate (100) by wet casting. For example, the silicone pressure sensitive adhesive composition may be applied to the surface (101b) of the backing substrate (101) and cured to form the silicone pressure sensitive adhesive (102). Alternatively, the silicone pressure sensitive adhesive composition may be applied to the surface (103a) of the fluorosilicone rubber article (103) and cured to form the silicone pressure sensitive adhesive (102). Alternatively, the silicone pressure sensitive adhesive composition may be applied to the surface of a release liner and cured to form the silicone pressure sensitive adhesive (102). The surface (103a) of the fluorosilicone rubber article (103) may then be brought into contact with the opposing surface (102b) of the silicone pressure sensitive adhesive (102), and the surface (101b) of the backing substrate (101) may be brought into contact with the surface (102a) of the silicone pressure sensitive adhesive (102). Pressure may be applied to adhere the layers of backing substrate (101), silicone pressure sensitive adhesive (102), and fluorosilicone rubber article (103) together.

[0048] Alternatively, wet casting may be used to prepare a laminated article comprising a backing substrate comprising fluorosilicone rubber or silicone foam, a silicone pressure sensitive adhesive as described above, and optionally a (second) article comprising fluorosilicone rubber or silicone foam. In this method, the backing substrate may be the same or different fluorosilicone rubber article or silicone foam as the article used in step (11) described below. Alternatively, the backing substrate may comprise more than one component material, such as a mesh (which may be fabricated from a polymeric material as described above) impregnated with fluorosilicone rubber. This method for fabricating a laminated article includes: (1) under conditions for carrying out a condensation reaction, (P) a bis-hydroxyl terminated polydiorganosiloxane having a weight average molecular weight of 10,000 g / mol to <200,000 g / mol as measured by GPC; (R) a hydroxyl-functional polyorganosilicate resin having a weight average molecular weight of 4,000 g / mol to <10,000 g / mol as measured by GPC; (S) solvent, and Optionally, a starting material comprising (N) a neutralizing agent, combining starting materials (R) and (P) to form a reaction mixture, wherein the starting materials (R) and (P) are present in a weight ratio (R) / (P) of from 0.76 / 1 to 2.15 / 1; (2) adding (C) a condensation reaction catalyst to the reaction mixture to form a catalyzed reaction mixture; (3) heating the catalytic reaction mixture at a temperature >RT to 145°C to remove water, thereby producing a condensation reaction mixture comprising the condensation reaction product of (P) and (R); Optionally, (4) recovering the condensation reaction product of (P) and (R); and optionally, (5) adding up to 4 weight percent, based on the combined weight of (R) and (P), of (X) a peroxide crosslinker to form a silicone pressure sensitive adhesive composition; Optionally, (6) treating the surface of the backing substrate comprising a fluorosilicone rubber or a silicone foam; and (7) coating a surface of a backing substrate with a silicone pressure sensitive adhesive composition; (8) drying the silicone pressure sensitive adhesive composition; and (9) curing the silicone pressure sensitive adhesive composition to form a silicone pressure sensitive adhesive layer having a surface adhered to a surface of a backing substrate, the silicone pressure sensitive adhesive layer further comprising an opposing surface opposite the surface of the backing substrate. Optionally, (10) treating a surface of an article comprising fluorosilicone rubber or silicone foam; and (11) adhering an opposing surface of the silicone pressure sensitive adhesive to a surface of an article; and Includes.

[0049] FIG. 2 shows a partial cross-section of a laminated article (200) prepared by the method described above. The laminated article (200) comprises a silicone pressure sensitive (202) having a surface (202a) and an opposing surface (202b). The silicone pressure sensitive agent (202) may have a thickness of 10 μm to 200 μm. The silicone pressure sensitive agent (202) comprises a fluorosilicone rubber (201) and is adhered to a backing substrate having a surface (201b), the peel adhesion being greater than 400 gf / in as measured by the test method described in the Examples below. The surface (202a) of the silicone pressure sensitive agent (202) is in contact with the surface (201b) of the backing substrate (201). The backing substrate (201) may be a fluorosilicone rubber article as described above. Alternatively, the backing substrate (201) may comprise a mesh impregnated with a fluorosilicone rubber.

[0050] The silicone pressure sensitive adhesive composition may be used in the fabrication of a laminate article (200) by wet casting. For example, the silicone pressure sensitive adhesive composition may be applied to a surface (201b) of a backing substrate (201) and cured to form a silicone pressure sensitive adhesive (202). EXAMPLES

[0051] The following examples are provided to illustrate the invention to one of ordinary skill in the art and should not be construed as limiting the scope of the invention as set forth in the claims. The starting materials used in these examples are listed in Table 1. [Table 1]

[0052] In this Reference Example 1, the condensation reaction product (thickened resin) was prepared as follows: PDMS polymer, MQ resin, solvent, and neutralizer were combined in a three-neck flask at RT. The contents of the flask were stirred at 250 rpm for 20 minutes with a stainless steel stirring paddle in the center neck. The condensation catalyst was then added while stirring. Another neck was connected to a Dean-Stark trap, which was then connected to a condenser with tap water cooling capability. The last neck contained a thermometer and a nitrogen sweep adapter to close the system. Finally, the three-neck flask with the mixture inside was attached to a heating mantle with temperature control and heated to a reaction temperature of 145°C. The reaction was allowed to continue for 3 hours starting from the start of reflux. Following this procedure, thickened resins IE1-IE7 and CE1-CE5 and CE7-CE17 were prepared.

[0053] In this Reference Example 2, a comparative silicone pressure sensitive adhesive composition CE6 was prepared as follows: The starting materials were added to a dental mixer cup and mixed at 3500 rpm for 30 seconds until homogenous. This cold blend (comparative) PSA was used immediately in the coating / curing process.

[0054] In this Reference Example 3, a peroxide crosslinker was added to form a peroxide curable silicone pressure sensitive adhesive composition that was coated onto a backing substrate and cured as follows. For the peroxide curable silicone pressure sensitive adhesive compositions (IE1-IE7 and CE1-CE18), peroxide crosslinker (in toluene) and solvent 1 were added to each composition prepared as described in Reference Examples 1 and 2 above in a dental mixer cup to reach a solids level of 50% by weight and a peroxide crosslinker level of 2% by weight. The resulting samples were mixed at 3500 rpm for 30 minutes until homogenous. Each sample was prepared for application testing by coating onto a 2 mil thick polyester (PET) sheet using a 3 mil coating bar. Each sheet was then cured in an oven at 80°C for 2 minutes followed by 180°C for 2 minutes.

[0055] The starting materials and the amounts used to prepare each sample are shown in Tables 2, 4 and 6 below.

[0056] In this Reference Example 4, a fluorosilicone rubber substrate was prepared as follows.

[0057] Liquid fluorosilicone rubber (F-LSR) substrate was obtained from DSC, SILASTIC™ FL 40-9201 Part A and Part B were dispensed through a 1:1 ratio meter mix system feeding a static mixer that fed into an injection molding machine. The mixed material was poured into a 6 inch x 6 inch x 0.078 inch slab mold and cured at 280° F. for 30 seconds. The slab was removed after the mold was opened and allowed to cool to room temperature.

[0058] In this Reference Example 5, the adhesion of the pressure sensitive adhesive prepared according to Reference Example 3 to the fluorosilicone rubber prepared according to Reference Example 4 and to a commercial silicone foam was measured as follows:

[0059] Peel Adhesion: Peel adhesion (180°) was tested according to PSTC-101 standard. Silicone pressure sensitive adhesive coated on 2 mil polyester film (tape) was laminated onto a silicone rubber surface, typically after 1 day of curing. The silicone rubber surface was wiped with isopropyl alcohol to clean the surface and allowed to dry for 5 minutes under ambient conditions before the silicone pressure sensitive adhesive was laminated onto it. After lamination, a rubber-coated 2 kg roller was applied to the resulting article (5 times each before and after), and the article was allowed to rest at room temperature for 20 minutes of dwell time before peel adhesion testing. A TMI peel and adhesion tester was used to pull a 1 inch wide tape from a silicone rubber substrate at 12 inches / minute. The results of the adhesion test are shown in Tables 3, 5 and 7 below. In the tables, CE indicates a comparative example, and IE indicates an example of the present invention. [Table 2] [Table 3]

[0060] In Tables 2 and 3, thickened resins with different resin to polymer ratios were prepared. When polyorganosilicate resins and (liquid) polymers with Mw described herein were used in silicone pressure sensitive adhesive compositions, these compositions cured to form silicone pressure sensitive adhesives with adhesion to F-LSR >400 g / in and to silicone foam >300 g / in (all IE1-IE6). The highest adhesion silicone pressure sensitive adhesives were produced from compositions with R / P between 0.93 / 1 and 1.40 / 1 (IE2, IE3, and IE4). Silicone pressure sensitive adhesives produced from comparative compositions with R / P outside the range of 0.76 / 1 to 2.15 / 1 showed poor adhesion to both F-LSR and silicone foam (CE1, CE2). [Table 4] [Table 5]

[0061] The data in Tables 2-5 show that when the R / P ratio was kept constant (0.93 / 1) by using resins with Mw that were too high (>10,000 g / mol) in Comparative Examples CE3, CE4, and CE 7-CE 9, or by using gums with Mw that were too high in Comparative Example CE5, the resulting silicone pressure sensitive adhesives exhibited poor adhesion to F-LSR and silicone foam compared to Example IE2. By using polyorganosilicate resins with Mw<10,000 g / mol in the compositions (IE2, IE3, and IE7), silicone pressure sensitive adhesives with good adhesion to both F-LSR and silicone foam were obtained. The low temperature blend PSA (CE6) exhibited very poor adhesion to F-LSR and silicone foam compared to the silicone pressure sensitive adhesives made from compositions containing thickened resin (IE2). [Table 6] [Table 7]

[0062] The data in Tables 6 and 7 show that the use of a polyorganosilicate resin with too high a molecular weight (>10,000 g / mol) in the comparative compositions resulted in pressure sensitive adhesives with poor adhesion to F-LSR and poor adhesion to silicone foam, with adhesive strengths to F-LSR of <200 gf / in and to silicone foam of <150 gf / in. [Table 8]

[0063] Under the conditions tested, the commercially available silicone PSAs exhibited poor adhesion to both F-LSR and silicone foam, <350 g / in to F-LSR and <300 g / in to silicone foam, as shown in Comparative Examples CE18 and CE19.

[0064] In this Example 6, samples of laminate articles were prepared by a method involving wet casting (Method 2) as follows: 1. Samples of silicone pressure sensitive adhesive compositions were prepared by mixing peroxide crosslinker (in toluene) and solvent 1 with each of composition IE4 and a commercial PSA (7406-VLO) (prepared as described above) in a dental mixer cup to reach a solids level of 50% by weight and a peroxide crosslinker level of 2% by weight. Each resulting sample was mixed at 3500 rpm for 30 seconds until homogenous. 2. Four substrates were prepared. Two were F-LSR prepared as described above in Reference Example 4. Two were silicone foam as described above. The surface of each substrate was cleaned by wiping with isopropyl alcohol and drying under ambient conditions for 5 minutes. 3. Each sample of the silicone pressure sensitive adhesive composition was coated onto the cleaned surface of a substrate using a 3 mil coating bar. Each coated substrate was then placed in an oven at 80° C. for 2 minutes, followed by 180° C. for 2 minutes to prepare a laminate of a (cured) silicone pressure sensitive adhesive layer on each sheet of substrate. 4. Four additional sheets of substrate were prepared, two of which were F-LSR and two of which were the silicone foam described above. The surface of each substrate was cleaned by wiping with isopropyl alcohol and allowing to dry under ambient conditions for 5 minutes. 5. One day after step 3, the surface of each silicone pressure sensitive adhesive layer was contacted with the cleaned surface of the substrate from step 4. Each resulting laminate had two F-LSR substrates with a silicone pressure sensitive adhesive between them, or two silicone foam substrates with a silicone pressure sensitive adhesive between them. A 2 kg rubber covered roller was applied to the resulting laminate (five strokes each), and the laminate was left at room temperature for a 20 minute dwell time before peel adhesion testing according to the PSTC-101 standard mentioned above (except that no polyester film was used as the backing substrate). A TMI peel and adhesion tester was used to pull the 1 inch wide tape from the substrate at 12 inches / minute. The peel adhesion test results are shown in Table 9 below. [Table 9]

[0065] The data in Table 9 show that silicone pressure sensitive adhesives prepared by the wet casting method, as described herein, have better adhesion to fluorosilicone rubber than commercially available silicone pressure sensitive adhesives applied to fluorosilicone rubber articles in the same manner.

[0066] In this Example 7, samples of laminate articles were prepared by a method involving dry casting (Method 3) as follows: 1. Two samples of silicone pressure sensitive adhesive compositions were prepared by mixing the peroxide crosslinker (in toluene) and solvent 1 with each of composition IE4 and a commercial PSA (7406-VLO) (prepared as described above) in a dental mixer cup to reach a solids level of 50% by weight and a peroxide crosslinker level of 2% by weight. Each resulting sample was mixed at 3500 rpm for 30 seconds until homogenous. 2. Each sample of the silicone pressure sensitive adhesive composition was coated onto a fluorosilicone release liner using a 3 mil coating bar. Each coated liner was then placed in an oven at 80° C. for 2 minutes, followed by 180° C. for 2 minutes to prepare a laminate of a (cured) silicone pressure sensitive adhesive layer on each fluorosilicone release liner. Each laminate was aged at room temperature for 1 day. 3. Four substrates were prepared. Two were F-LSR prepared as described above in Reference Example 4. Two were silicone foam as described above. The surface of each substrate was cleaned by wiping with isopropyl alcohol and drying under ambient conditions for 5 minutes. 4. A surface of each silicone pressure sensitive adhesive layer from Step 2 was contacted with the cleaned surface of each substrate from Step 3. 5. Four substrates were prepared. Two were F-LSR prepared as described above in Reference Example 4. Two were silicone foam as described above. The surface of each substrate was cleaned by wiping with isopropyl alcohol and drying under ambient conditions for 5 minutes. 6. One day after step 4, the fluorosilicone release liner was removed from each laminate and the exposed surface of each resulting silicone pressure sensitive adhesive layer was contacted with the cleaned surface of the substrate from step 5. Each resulting laminate had two F-LSR substrates with a silicone pressure sensitive adhesive between them or two silicone foam substrates with a silicone pressure sensitive adhesive between them. A 2 kg rubber covered roller was applied to the resulting laminate (five strokes each) and the laminate was left at room temperature for a 20 minute dwell time before peel adhesion testing according to the PSTC-101 standard mentioned above (except that no polyester film was used as the backing substrate). A 1 inch wide tape from the silicone rubber substrate was pulled at 12 inches / minute using a TMI peel and adhesion tester. The peel adhesion test results are shown in Table 10 below. [Table 10]

[0067] The data in Table 10 show that silicone pressure sensitive adhesives prepared by the wet casting method, as described herein, have better adhesion to fluorosilicone rubber than commercially available silicone pressure sensitive adhesives applied to fluorosilicone rubber articles in the same manner.

[0068] Definitions and Use of Terms All amounts, ratios and percentages are by weight unless otherwise indicated. The amounts of all starting materials in the composition total 100% by weight. The Summary and Abstract of the Invention are incorporated herein by reference. The articles "a", "an" and "the" each refer to one or more, unless otherwise indicated by the context of the specification. The singular includes the plural unless otherwise indicated. The terms "comprising" and its derivatives, such as "comprise" and "comprises", are used herein in their broadest sense to mean and include the notions "including", "include", "consist(ing) essentially of", and "consist(ing) of". The use of "for example", "eg", "such as", and "including" to list examples is not limited to only the examples listed. Thus, "for example" or "such as" means "for example, but not limited to" or "such as, but not limited to," and includes other similar or equivalent examples.

[0069] It is to be understood that the appended claims are not limited to the specific compounds, compositions, or methods described therein for purposes of describing the "Description of the Invention" and may vary among specific embodiments within the scope of the appended claims. With respect to any Markush group relied upon in this specification to describe particular features or aspects of various embodiments, different, special, and / or unexpected results may result from each element of the respective Markush group independent of all other Markush elements. Each element of the Markush group may be relied upon individually and / or in combination to provide adequate support for specific embodiments within the scope of the appended claims.

[0070] Abbreviations used herein are defined in Table 11. [Table 11]

[0071] The Mn, Mw, and molecular weight distribution of the polymer and condensation reaction product can be determined by GPC using an Agilent Technologies 1260 Infinity chromatograph and toluene as the solvent. The instrument is equipped with two PLgel Mixed C columns. Calibration was performed using polystyrene standards. Samples were prepared by dissolving the polymer in toluene (approximately 10 mg / mL) and then immediately analyzing the material by GPC (flow rate 1 mL / min and column temperature 45° C.).

[0072] The Mn, Mw, and molecular weight distribution of the resin can be determined by GPC using an Agilent Technologies 1260 Infinity chromatograph and ethyl acetate as the solvent. The instrument is equipped with two columns, an Agilent PLgel Mixed-D and a PLgel Mixed-E column. Calibration was performed using polystyrene standards. Samples were prepared by dissolving the polymer in toluene (approximately 20 mg / mL) and then immediately analyzing the material by GPC (flow rate 1 mL / min and column temperature 35° C.).

Claims

1. 1. A method of making a laminate, comprising: (1) Under conditions for carrying out a condensation reaction, (P) a bis-hydroxyl terminated polydiorganosiloxane having a weight average molecular weight of 10,000 g / mol to <200,000 g / mol as measured by GPC; (R) Hydroxyl-functional polyorganosilicate resins having a weight average molecular weight of 4,000 g / mol to <10,000 g / mol as measured by GPC (S) a solvent, and Optionally, (N) a neutralizing agent, combining starting materials (R) and (P) to form a reaction mixture, wherein the starting materials (R) and (P) are present in a weight ratio (R) / (P) of from 0.76 / 1 to 2.15 / 1; (2) adding (C) a condensation reaction catalyst to the reaction mixture to form a catalytic reaction mixture; (3) heating the catalyst reaction mixture at a temperature >RT to 145°C to remove water; optionally, (4) recovering the condensation reaction product of (P) and (R); optionally, (5) adding up to 4 wt. %, based on the combined weight of (R) and (P), of (X) a peroxide crosslinker to form a silicone pressure sensitive adhesive composition; Optionally, (6) treating the surface of the backing substrate; and (7) coating the surface of the backing substrate with the silicone pressure-sensitive adhesive composition; (8) drying the silicone pressure-sensitive adhesive composition; and (9) curing the silicone pressure-sensitive adhesive composition to form a silicone pressure-sensitive adhesive layer having a surface adhered to the surface of the backing substrate, the silicone pressure-sensitive adhesive layer further comprising an opposing surface opposite the surface of the backing substrate; Optionally, (10) treating the surface of the article comprising fluorosilicone rubber or silicone foam; (11) adhering the opposing surface of the silicone pressure sensitive adhesive to the surface of the article; A method comprising:

2. The starting material (P), the bis-hydroxyl terminated polydiorganosiloxane, is represented by the formula 【Chemistry 1】 (In the formula, each R １ are independently selected alkyl groups of 1 to 6 carbon atoms, and the subscript a represents the average number of difunctional siloxane units per molecule, where 250≦a≦3,000.

3. The starting material (R), the hydroxyl-functional polyorganosilicate resin, has the unit formula (R １ ３ SiO １／２ ) ｂ (SiO ４／２ ) ｃ (HO １／２ ) ｄ (In the formula, each R １ are independently selected alkyl groups of 1 to 6 carbon atoms; subscripts b and c represent the mole fractions of monofunctional and tetrafunctional units, respectively, with subscripts b and c having values ​​such that 0.4≦b≦0.5, 0.5≦c≦0.6, and the quantity (b+c)=1; subscript d represents the amount of hydroxyl groups in the resin, with subscript d having a value sufficient to provide the resin with a hydroxyl content of 2% to 5% by weight; and the polyorganosilicate resin has a weight average molecular weight of 5,000 g / mol to 9,000 g / mol.

4. Each R １ The method of claim 2, wherein is methyl.

5. 2. The method of claim 1, wherein (R) / (P) is from 0.93 / 1 to 1.40 / 1.

6. 10. The method of claim 1, wherein (N) the neutralizing agent is present and the neutralizing agent comprises a silyl phosphate.

7. (C) The method of claim 1, wherein the condensation reaction catalyst is an acid.

8. 10. The method of claim 1, wherein step (5) is present and (X) the peroxide crosslinker comprises benzoyl peroxide.

9. The method of claim 1 , wherein step (6) is present and step (6) comprises applying a primer to the surface of the backing substrate.

10. 10. The method of claim 1, wherein step (10) is present and step (10) comprises cleaning the surface of the article with alcohol.

11. 10. The method of claim 1, wherein in step (11), the article is a fluorosilicone rubber having a durometer of 30-60.

12. A laminate prepared by the method of any one of claims 1 to 11.

13. wherein the backing substrate in step (7) comprises a release liner, and the method further comprises: removing the release liner after step (9); Optionally, (12) treating the surface of a second article comprising fluorosilicone rubber or silicone foam; and 13. The method of claim 1, further comprising adhering the surface of the silicone pressure sensitive adhesive layer to the surface of the second article.

14. 1. A method of making a laminate, comprising: (1) Under conditions for carrying out a condensation reaction, (P) a bis-hydroxyl terminated polydiorganosiloxane having a weight average molecular weight of 10,000 g / mol to <200,000 g / mol as measured by GPC; (R) a hydroxyl-functional polyorganosilicate resin having a weight average molecular weight of 4,000 g / mol to <10,000 g / mol as measured by GPC; (S) a solvent, and Optionally, (N) a neutralizing agent, combining starting materials (R) and (P) to form a reaction mixture, wherein the starting materials (R) and (P) are present in a weight ratio (R) / (P) of from 0.76 / 1 to 2.15 / 1; (2) adding (C) a condensation reaction catalyst to the reaction mixture to form a catalytic reaction mixture; (3) heating the catalyst reaction mixture at a temperature >RT to 145°C to remove water, thereby producing a condensation reaction mixture comprising the condensation reaction product of (P) and (R); optionally, (4) recovering the condensation reaction product of (P) and (R); optionally, (5) adding up to 4 wt. %, based on the combined weight of (R) and (P), of (X) a peroxide crosslinker to form a silicone pressure sensitive adhesive composition; Optionally, (6) treating the surface of the backing substrate with a fluorosilicone rubber; and (7) coating the surface of the backing substrate with the silicone pressure-sensitive adhesive composition; (8) drying the silicone pressure-sensitive adhesive composition; and (9) curing the silicone pressure-sensitive adhesive composition to form a silicone pressure-sensitive adhesive layer having a surface adhered to the surface of the backing substrate, the silicone pressure-sensitive adhesive layer further comprising an opposing surface opposite the surface of the backing substrate.

15. Optionally, (10) treating the surface of the article to include fluorosilicone rubber; and 11. The method of claim 14, further comprising adhering the opposing surface of a silicone pressure sensitive adhesive to the surface of the article.

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