Curable compositions for silicone pressure sensitive adhesives

Abstract

A curable composition comprising: (A) a polydiorganosiloxane component comprising: (A1) greater than 3.1 wt% to 20 wt% of an aliphatically unsaturated polydiorganosiloxane polymer and (A3) a hydroxyl terminated polydiorganosiloxane gum of unit formula (A-III); (B) a polyorganosilicate resin component comprising (B1) an endcapped resin, (B2) > 18.53 wt% to 54.3 wt% of an unendcapped resin; wherein the weight ratio of the unendcapped resin (B2) to the endcapped resin (B1) is greater than 0.51 to 58.82; wherein component (A) and component (B) are present in amounts to provide a weight ratio of (B):(A) of 1.2:1 to less than 1.62:1; (C) a polyorganohydrogensiloxane present in an amount to provide a molar ratio of silicon-bonded hydrogen atoms to alkenyl groups of the curable composition of 5 to 50; (D) a hydrosilylation reaction catalyst in an amount sufficient to provide 1 ppm to 1000 ppm of platinum group metal; and (E) a condensation reaction catalyst; wherein the content of alkenyl groups in the curable composition is 0.017 wt% to 0.089 wt%; and wherein the wt% values are relative to the total weight of components (A), (B), (C), (D), and (E) unless otherwise specified.

Description

Technical Field

[0001] This invention relates to curable compositions and methods for preparing such curable compositions. Specifically, this invention relates to compositions that can be hydrosilylated and condensed to cure, which cure to form silicone pressure-sensitive adhesives. Background Technology

[0002] Protective films and carrier tapes are two major applications of silicone pressure-sensitive adhesives in the electronics manufacturing industry. Typically, during the manufacturing of electronic devices, various components of protective films and carrier tapes are laminated together with the adhesive to form multiple layers, and it is important that each layer adheres to the others and is not subjected to damage that could lead to component failure. These multiple layers typically include a protective film adhered to the adhesive used in the manufacture of the electronic device (e.g., graphite sheets, copper foil, or ultra-thin double-sided tape) to protect the adhesive from scratches and other damage during processing and / or transportation. It is desirable for such protective films to peel cleanly from the adhesive, leaving no residue identifiable to the end user of the electronic device. This typically requires the protective film to have low adhesion to the adhesive, such as an adhesion force of less than 10 grams per inch to stainless steel according to ASTM D3330. However, such low-adhesion silicone protective films may have the disadvantage of difficulty in forming rapid and strong adhesion to other layers when manufacturing consumer electronics.

[0003] Therefore, there is an industrial need for a silicone pressure-sensitive adhesive that can adhere to low-adhesion silicone protective films with the desired adhesive properties. Summary of the Invention

[0004] This invention provides a novel curable composition that can be cured to achieve high adhesion (i.e., ≥400 g / in) to a low-adhesion silicone protective film. "Low-adhesion silicone protective film" refers to a protective film having a low-adhesion silicone pressure-sensitive adhesive, which differs from the silicone pressure-sensitive adhesive of this invention and exhibits adhesion to stainless steel <10 g / in. Adhesion characteristics were measured according to ASTM D3330 using an AR 1500 adhesion / peel tester. The curable composition of this invention comprises a novel combination of aliphatic unsaturated polydiorganosiloxane polymers, hydroxyl-terminated polydiorganosiloxane adhesives, terminated polyorganosilicate resins, unterminated polyorganosilicate resins, polyorganohydrosiloxanes, hydrosilylation catalysts, and condensation catalysts. The curable composition of this invention is particularly suitable for forming silicone pressure-sensitive adhesives. This curable composition can be cured via both hydrosilylation and condensation reactions (i.e., hydrosilylation and condensation curable composition) to prepare a pressure-sensitive adhesive (also known as "hydrosilylation / condensation dual-curing PSA").

[0005] In a first aspect, the present invention is a curable composition comprising:

[0006] (A) A polydiorganosiloxane component, the polydiorganosiloxane component comprising:

[0007] (A1) Greater than 3.1% to 20% by weight of an aliphatic unsaturated polydiorganosiloxane polymer of formula (AI):

[0008] R M (3-c) R U c SiO-(R U R M SiO) a -(R M 2SiO) b -SiR U d R M (3-d) (AI)

[0009] Each R M Independently selected from groups consisting of monovalent hydrocarbon groups of 1 to 30 carbon atoms without aliphatic unsaturation and monovalent halohydrocarbon groups without aliphatic unsaturation; each R U Independently an alkenyl group; and the average of the subscripts a, b, c, and d such that a ≥ 0, b > 0, c is zero or 1, d is zero or 1, the number (a+b) is 100 to 2000, and the number (a+c+d) ≥ 2; and

[0010] (A3) Hydroxyl-terminated polydiorganosiloxane adhesives of unit formula (A-III):

[0011] {(HO)R M 2SiO 1 / 2}2(R M 2SiO 2 / 2 ) e (A-III)

[0012] Each R MIndependently selected from the group consisting of monovalent hydrocarbon groups of 1 to 30 carbon atoms without aliphatic unsaturation and monovalent halohydrocarbon groups without aliphatic unsaturation; and the subscript e having a value sufficient to impart 20 mils (0.51 mm) to 80 mils (2.03 mm) of plasticity to the hydroxyl-terminated polydiorganosiloxane resin (A3), wherein the plasticity is measured based on ASTM D926 by applying a 1 kg load to a 4.2 g spherical sample at 25 °C for 3 minutes, and the result is measured in thousandths of an inch (mil), and the procedure is based on ASTM D926; it is present in an amount providing a weight ratio of 0.89:1 to 9.33:1 of the hydroxyl-terminated polydiorganosiloxane resin (A3) to the aliphatic unsaturated polydiorganosiloxane polymer (A1);

[0013] (B) A polyorganosilicate resin component, the polyorganosilicate resin component comprising:

[0014] (B1) Unitary (BI) end-capping resin: (R M 3SiO 1 / 2 ) z (SiO 4 / 2 ) o Z f , where R M The group consists of monovalent hydrocarbon groups of 1 to 30 carbon atoms without aliphatic unsaturation and monovalent halohydrocarbon groups without aliphatic unsaturation, each Z being a hydrolyzable group, the subscript f being zero to a value sufficient to impart at most 2% hydrolyzable group content to the end-capping resin, and the subscripts z and o being such that o>1, z>4, and the quantity (o+z) having a number average molecular weight value sufficient to provide the end-capping resin with 500 g / mol to <7,000 g / mol;

[0015] (B2) More than 18.53% to 54.3% by weight of uncapped monomeric (B-II) resins: (R M 3SiO 1 / 2 ) z' (SiO 4 / 2 ) o' Z f' , where R M The uncapped resin is independently selected from a group consisting of monovalent hydrocarbon groups of 1 to 30 carbon atoms without aliphatic unsaturation and monovalent halohydrocarbon groups without aliphatic unsaturation, each Z being an independently hydrolyzable group, the subscript f' having a value sufficient to impart a hydrolyzable group content of greater than 3% to 10%, and the subscripts z' and o' having values ​​such that o'>1, z'>4, and the quantity (o'+z') having a number average molecular weight value sufficient to provide the uncapped resin with 500 g / mol to <7,000 g / mol;

[0016] The weight ratio of the uncapped resin (B2) to the capped resin (B1) is greater than 0.51 to 58.82.

[0017] The polydiorganosiloxane component (A) and the polyorganosilicate resin component (B) are present in an amount providing a weight ratio of (B) to (A) of 1.2:1 to less than 1.62:1;

[0018] (C) Monomeric (CI) polyorganohydrosiloxanes:

[0019] (R M 3SiO 1 / 2 ) p (R M 2SiO 2 / 2 ) q (R M SiO 3 / 2 ) r (SiO 4 / 2 ) s (R M HSiO 2 / 2 ) t (R M 2HSiO 1 / 2 ) u (CI),

[0020] Where R M As described above in formula (AI), and the values ​​of the subscripts p, q, r, s, t, and u are such that p ≥ 0, q ≥ 0, r ≥ 0, s ≥ 0, t ≥ 0, u ≥ 0, (t + u) ≥ 2, and the quantity (p + q + r + s + t + u) is sufficient to provide the polyorganohydrosiloxane with a degree of polymerization of 5 to 100; which provides the curable composition with an amount of 5 to 50 molar ratio of silicon-bonded hydrogen atoms to alkenyl groups;

[0021] (D) A hydrosilylation catalyst, wherein the amount of the hydrosilylation catalyst is sufficient to provide 1 ppm to 1000 ppm of platinum group metals; and

[0022] (E) Condensation reaction catalyst;

[0023] The content of alkenyl groups in the curable composition is in the range of 0.017% by weight to 0.089% by weight;

[0024] The weight percentage is relative to the combined weight of components (A), (B), (C), (D), and (E).

[0025] In a second aspect, the present invention is a method for preparing the curable composition of the first aspect. The method includes:

[0026] i) mix the hydroxyl-terminated polydiorganosiloxane adhesive (A3), the unterminated resin (B2), and the condensation reaction catalyst (E); and ii) further mix the resulting mixture obtained in step i) with the aliphatic unsaturated polydiorganosiloxane polymer (A1), the terminating resin (B1), the polyorganohydrosiloxane (C), and the hydrosilylation reaction catalyst (D); thereby forming the curable composition.

[0027] In a third aspect, the present invention is an adhesive article comprising a substrate and a silicone pressure-sensitive adhesive on at least one surface of the substrate, wherein the silicone pressure-sensitive adhesive is a cured product of the curable composition of the first aspect.

[0028] In a fourth aspect, the present invention is a method for preparing an adhesive article. The method includes: optionally (1) treating the surface of a substrate; (2) applying the curable composition of the first aspect to at least one surface of the substrate; and (3) curing the curable composition. Attached Figure Description

[0029] Figure 1 A partial cross-section of the adhesive article 100 is shown. The adhesive article comprises a pressure-sensitive adhesive 102 prepared by curing a curable composition described herein onto a surface 101 of a film substrate 101. The article 100 also includes a low-adhesion silicone protective film 200 adhered to the opposite surface of the pressure-sensitive adhesive 102. Detailed Implementation

[0030] When a test method number is not used to indicate a date, the test method refers to the most recent test method as of the priority date of this document. References to test methods include references to both the testing association and the test method number. The following test method abbreviations and designations apply to this document: ASTM refers to the ASTM International Association Method.

[0031] Products identified by their trade names refer to compositions available under those trade names as of the priority date of this document.

[0032] "And / or" means "and, or as an alternative." Unless otherwise specified, all ranges include the endpoints.

[0033] The “viscosity” of polydiorganosiloxanes (such as component (A1)) is measured at 25 degrees Celsius (°C) using the rotational viscometer method according to ASTM 1084, unless otherwise stated.

[0034] The “plasticity” of polydiorganosiloxane adhesive is measured based on ASTM D926 by applying a 1 kg load to a 4.2 g spherical sample at 25°C for 3 minutes, and the results are measured in thousandths of an inch (mil), and the procedure is based on ASTM D926 unless otherwise stated.

[0035] The chemical structures of polydiorganosiloxanes, polyorganosilicate resins, or polyorganohydrosiloxanes are determined by standard... 1 H, 13 C and 29 The determination was made using nuclear magnetic resonance (NMR) analysis of Si.

[0036] "Adhesion" characteristics are determined using an AR 1500 adhesion / peel tester according to ASTM D3330, unless otherwise specified.

[0037] Unless otherwise stated, number-average molecular weight (Mn) refers to the number-average molecular weight measured using gel permeation chromatography (GPC), and weight-average molecular weight (Mw) refers to the weight-average molecular weight measured using GPC. For example, a GPC test method suitable for measuring Mn and Mw is disclosed in Reference Example 1, paragraph 31, of U.S. Patent 9,593,209.

[0038] The curable composition of the present invention comprises components (A), (B), (C), (D), and (E), as well as optional components described below. The curable composition comprises (A) a polydiorganosiloxane component (component (A)). The polydiorganosiloxane component (A) may comprise or consist of: (A1) an aliphatic unsaturated polydiorganosiloxane polymer (also referred to as "Vi polymer") and (A3) a hydroxyl-terminated polydiorganosiloxane adhesive (also referred to as "OH adhesive"), and optionally (A2) an aliphatic unsaturated polydiorganosiloxane adhesive (also referred to as "Vi adhesive").

[0039] The aliphatic unsaturated polydiorganosiloxane polymer (A1) (component (A1)) has the formula (AI):

[0040] R M (3-c) R U c SiO-(R U R M SiO) a -(R M 2SiO) b -SiR U d R M (3-d) (AI)

[0041] Each RM Independently selected groups consisting of monovalent hydrocarbon groups of 1 to 30 carbon atoms without aliphatic unsaturation and monovalent halohydrocarbon groups of 1 to 30 carbon atoms without aliphatic unsaturation, each R U Independently an alkenyl group, the average of the subscripts a, b, c, and d is such that a ≥ 0, b > 0, c is zero or 1, d is zero or 1, the number (a+b) is between 100 and 2000, and the number (a+c+d) ≥ 2. Used for R M Suitable monovalent hydrocarbon groups and monovalent halohydrocarbon groups are defined as follows. Each R M It can have 1 to 30 carbon atoms, and can be 1 to 12 carbon atoms, 1 to 10 carbon atoms, 1 to 6 carbon atoms, 1 to 4 carbon atoms, 1 to 2 carbon atoms, or even 1 carbon atom. Each R M It can be independently an alkyl group, an aryl group, or an aralkyl group as defined below. Ideally, each R M It is an alkyl or aryl group with 1 to 6 carbon atoms, such as a phenyl group. More ideally, each R M It is a methyl group. Each R U It can be an alkenyl group independently, as defined below. Each R U It can have 2 to 12 carbon atoms, 2 to 10 carbon atoms, 2 to 6 carbon atoms, 2 to 4 carbon atoms, or even 2 carbon atoms. Ideally, each R... U The components are independently selected from the group consisting of vinyl, allyl, and hexenyl groups. Alternatively, the amount (a+b) may have a value sufficient to impart a viscosity of 300 mPa·s to 100,000 mPa·s to the aliphatic unsaturated polydiorganosiloxane polymer, and may be 350 mPa·s to 90,000 mPa·s, 400 mPa·s to 80,000 mPa·s, or 450 mPa·s to 70,000 mPa·s. Ideally, the aliphatic unsaturated polydiorganosiloxane polymer (A1) has a viscosity of 450 mPa·s to 40,000 mPa·s. Alternatively, the quantity (a+b) may have a value of Mn sufficient to impart 5,000 g / mol to 100,000 g / mol, 10,000 g / mol to 100,000 g / mol, 11,000 g / mol to 90,000 g / mol, or 11,500 g / mol to 90,000 g / mol to the aliphatic unsaturated polydiorganosiloxane polymer, and ideally, the aliphatic unsaturated polydiorganosiloxane polymer has an Mn of 10,000 g / mol to 40,000 g / mol, as measured by GPC. Ideally, in formula (AI), each R M Alkyl groups, independently of 1 to 6 carbon atoms, such as methyl; each R UThe components are independently selected from the group consisting of vinyl, allyl, and hexenyl groups; and the quantity (a+b) has a value sufficient to impart a viscosity of 300 mPa·s to 100,000 mPa·s to the aliphatic unsaturated polydiorganosiloxane polymer.

[0042] “Alkyl” means a cyclic, branched, or unbranched saturated monovalent hydrocarbon group. Examples of alkyl groups include, but are not limited to, methyl, ethyl, propyl (e.g., isopropyl and / or n-propyl), butyl (e.g., isobutyl, n-butyl, tert-butyl, and / or sec-butyl), pentyl (e.g., isopentyl, neopentyl, and / or tert-pentyl), hexyl, heptyl, octyl, nonyl, and decyl, as well as branched alkyl groups having 6 or more carbon atoms; and cyclic alkyl groups, such as cyclopentyl and cyclohexyl. Alkyl groups have 1 to 12 carbon atoms and can have 1 to 10 carbon atoms, 1 to 6 carbon atoms, 1 to 4 carbon atoms, 1 to 2 carbon atoms, or even 1 carbon atom. “Aryl” means a cyclic, fully unsaturated hydrocarbon group. Examples of aryl groups include, but are not limited to, cyclopentadienyl, phenyl, anthracene, and naphthyl. Monocyclic aryl groups may have 5 to 9 carbon atoms, alternatively 6 to 7 carbon atoms, and alternatively 5 to 6 carbon atoms. Polycyclic aryl groups may have 10 to 17 carbon atoms, alternatively 10 to 14 carbon atoms, and alternatively 12 to 14 carbon atoms. "Aryl group" means an alkyl group having a side-chain aryl group and / or a terminal aryl group, or an aryl group having a side-chain alkyl group. Exemplary aryl groups include tolyl, xylyl, benzyl, phenethyl, phenylpropyl, and phenylbutyl.

[0043] "Alkenyl" refers to a branched or unbranched monovalent hydrocarbon group having one or more carbon-carbon double bonds. Examples of suitable alkenyl groups include vinyl, allyl, butenyl, pentenyl, hexenyl, and heptenyl (including branched and straight-chain isomers with 3 to 7 carbon atoms); and cyclohexenyl. Ideally, the alkenyl group is selected from the group consisting of vinyl, allyl, or hexenyl.

[0044] "Monovalent hydrocarbon group" refers to a monovalent group composed of hydrogen and carbon atoms. Monovalent hydrocarbon groups include alkyl, aralkyl, alkenyl, and cycloalkyl groups as defined above.

[0045] "Monovalent haloalkyl group" refers to a monovalent hydrocarbon group in which one or more hydrogen atoms bonded to a carbon atom have been formally replaced by halogen atoms. Haloalkyl groups include haloalkyl groups, halocarbocyclic groups, and haloalkenyl groups. Halogenated alkyl groups include fluorinated alkyl groups and fluorinated cycloalkyl groups, such as trifluoromethyl (CF3), fluoromethyl, trifluoroethyl, 2-fluoropropyl, 3,3,3-trifluoropropyl, 4,4,4-trifluorobutyl, 4,4,4,3,3-pentafluorobutyl, 5,5,5,4,4,3,3-heptafluoropentyl, 6,6,6,5,5,4,4,3,3-nonafluorohexyl, 8,8,8,7,7-pentafluorooctyl, 2,2-difluorocyclopropyl, 2,3-difluorocyclobutyl, 3,4-difluorocyclohexyl, and 3,4-difluoro-5-methylcycloheptyl; and chlorinated alkyl and chlorinated cycloalkyl groups, such as chloromethyl, 3-chloropropyl, 2,2-dichlorocyclopropyl, and 2,3-dichlorocyclopentyl. Halogenated alkenyl groups include chloroallyl.

[0046] Aliphatic unsaturated polydiorganosiloxane polymers (A1) may comprise a polydiorganosiloxane of formula (AI) or may be a combination of two or more polydiorganosiloxanes of formula (AI) that differ in one or more properties, such as viscosity, molecular weight, structure, siloxane units and sequence. Aliphatic unsaturated polydiorganosiloxane polymers suitable for use as component (A1) in curable compositions may comprise any combination of one or more of the following polydiorganosiloxanes: i) dimethylvinylsiloxy-terminated polydimethylsiloxane; ii) dimethylvinylsiloxy-terminated poly(dimethylsiloxane / methylphenylsiloxane); iii) dimethylvinylsiloxy-terminated poly(dimethylsiloxane / diphenylsiloxane); iv) phenyl, methyl, vinylsiloxy-terminated polydimethylsiloxane; v) dimethylhexenylsiloxy-terminated polydimethylsiloxane; iv) dimethylvinylsiloxy-terminated poly(dimethylsiloxane / methylhydrosiloxane); and vii) trimethylsiloxy-terminated poly(dimethylsiloxane / vinylmethylhydrosiloxane). Ideally, aliphatic unsaturated polydiorganosiloxane polymers are selected from the group consisting of: bis-vinyldimethylsiloxy-terminated polydimethylsiloxanes, bis-vinyldimethylsiloxy-terminated polydimethylsiloxanes, bis-vinyldimethylsiloxy-terminated polydimethylsiloxanes, dimethylvinylsiloxy-terminated poly(dimethylsiloxane / methylhydrosiloxane), trimethylsiloxy-terminated poly(dimethylsiloxane / vinylmethylhydrosiloxane), or mixtures thereof. Methods for preparing aliphatic unsaturated polydiorganosiloxanes (such as the hydrolysis and condensation of corresponding organohalosilanes or the equilibration of cyclic polydiorganosiloxanes) are well known in the art.

[0047] Aliphatic unsaturated polydiorganosiloxane polymers (A1) can be present at concentrations greater than 3.1 (>3.1) wt%, and can be 3.3 wt% or greater, 3.5 wt% or greater, 3.7 wt% or greater, 3.9 wt% or greater, 4.0 wt% or greater, 4.1 wt% or greater, 4.2 wt% or greater, 4.3 wt% or greater, 4.4 wt% or greater, 4.5 wt% or greater, 4.6 wt% or greater, 4.7 wt% or greater, 4.8 wt% or greater, 4.9 wt% or greater, or even 5% or greater, while typically present at concentrations of 20 wt% or less. The concentration of the aliphatic unsaturated polydiorganosiloxane polymer is 19.8% by weight or less, 19.5% by weight or less, 19.1% by weight or less, 18% by weight or less, 17% by weight or less, 16.4% by weight or less, 16% by weight or less, 15% by weight or less, 14% by weight or less, 11% by weight or less, 10% by weight or less, 9.1% by weight or less, 8% by weight or less, 5% by weight or less, or even 4.9% by weight or less, and ideally, the aliphatic unsaturated polydiorganosiloxane polymer is present at a concentration of 5% by weight to 16% by weight; based on the combined weight of components (A), (B), (C), (D) and (E).

[0048] Polydiorganosiloxane component (A) may or may not contain aliphatic unsaturated polydiorganosiloxane adhesive of formula (A-II) (component (A2)):

[0049] R M (3-c') R U c' SiO-(R U R M SiO) a' -(R M 2SiO) b' -SiR U d' R M (3-d') (A-II)

[0050] Each R M As described above in equation (AI), each R UAs stated above in Equation (AI), the average values ​​of subscripts a', b', c', and d' make a' ≥ 0, b' > 0, c' zero or 1, d' zero or 1, and (a' + c' + d) ≥ 2; and the quantity (a' + b') has a value sufficient to impart plasticity to (A-2) aliphatic unsaturated polydisiloxane resin from 20 mils (0.51 mm) to 80 mils (2.03 mm), 30 mils (0.76 mm) to 70 mils (1.78 mm), and 50 mils (1.27 mm) to 65 mils (1.65 mm), where plasticity is measured according to ASTM D926 (further details are provided above). Typically, the quantity (a' + b') can have a value > 2000, and can be 3000 or greater, 4000 or greater, or even 5000 or greater.

[0051] Aliphatic unsaturated polydiorganosiloxane adhesives are known in the art and can be prepared by methods such as hydrolysis and condensation of corresponding organohalosilanes or equilibration of cyclic polydiorganosiloxanes. Aliphatic unsaturated polydiorganosiloxane adhesives (A2) may comprise a combination of two or more polydiorganosiloxane adhesives of different unit formulas (A-II) in terms of one or more properties, such as plasticity, structure, siloxane units, and sequence. Suitable aliphatic unsaturated polydiorganosiloxane adhesives used as component (A2) in a curable composition may include any combination of one or more of the following polydiorganosiloxane adhesives:

[0052] i) Dimethylvinylsiloxy-terminated polydimethylsiloxane

[0053] ii) Dimethylvinylsiloxy-terminated poly(dimethylsiloxane / methylphenyl)siloxane,

[0054] iii) Dimethylvinylsiloxy-terminated poly(dimethylsiloxane / diphenyl)siloxane,

[0055] iv) Phenyl, methyl, vinyl-siloxy-terminated polydimethylsiloxanes

[0056] v) Dimethylhexenylsiloxy-terminated polydimethylsiloxane

[0057] vi) Dimethylhexenylsiloxy-terminated poly(dimethylsiloxane / methylphenyl)siloxanes, and

[0058] vii) Dimethylvinylsiloxy-terminated poly(dimethylsiloxane / diphenyl)siloxane.

[0059] Ideally, the polydiorganosiloxane adhesive is selected from the group consisting of: i) dimethylvinylsiloxy-terminated polydimethylsiloxane; v) dimethylhexenylsiloxy-terminated polydimethylsiloxane; or mixtures thereof.

[0060] Based on the combined weights of components (A), (B), (C), (D), and (E), aliphatic unsaturated polydiorganosiloxane adhesive (A2) can be present at a concentration of zero or greater, and can be greater than zero (>0), while typically present at a concentration of 7% by weight or less, and can be 6% by weight or less, 5% by weight or less, 3% by weight or less, 1.1% by weight or less, 1% by weight or less, or even 0.1% by weight or less. Alternatively, based on the combined weights of components (A), (B), (C), (D), and (E), the aliphatic unsaturated polydiorganosiloxane adhesive (A2) can be present in an amount of >3.1 wt% of the total concentration of the aliphatic unsaturated polydiorganosiloxane polymer (A1) and the aliphatic unsaturated polydiorganosiloxane adhesive (A2), and can be 3.3 wt% or greater, 3.5 wt% or greater, 3.7 wt% or greater, 3.9 wt% or greater, 4.0 wt% or greater, 4.1 wt% or greater, 4.2 wt% or greater, 4.3 wt% or greater, 4.4 wt% or greater, 4 0.5% by weight or more, 4.6% by weight or more, 4.7% by weight or more, 4.8% by weight or more, or even 4.9% by weight or more, while typically 20% by weight or less, and may be 19.8% by weight or less, 19.5% by weight or less, 19.1% by weight or less, 18% by weight or less, 17% by weight or less, 16.4% by weight or less, 15% by weight or less, 14% by weight or less, 11% by weight or less, 10% by weight or less, 9.1% by weight or less, 8% by weight or less, 5% by weight or less, or even 4.9% by weight or less.

[0061] Polydiorganosiloxane component (A) also contains hydroxyl-terminated polydiorganosiloxane adhesives of unit formula (A3) (“OH adhesives”, component (A3)):

[0062] {(HO)R M 2SiO 1 / 2}2(R M 2SiO 2 / 2 ) e (A-III)

[0063] Each R MAs described above in formula (AI); and the subscript e has a value sufficient to impart 20 mils (0.51 mm) to 80 mils (2.03 mm) of plasticity to the (A3) hydroxyl-terminated polydisiloxane, and may be 30 mils (0.76 mm) or greater, 50 mils (1.27 mm) or greater, or even 53 mils (1.27 mm) or greater, while may be 70 mils (1.78 mm) or less, 65 mils (1.65 mm) or less, or even 60 mils (1.65 mm) or less; wherein the plasticity is measured according to ASTM D926 (further details are provided above). Alternatively, the subscript e may have a value of Mn (as measured by GPC) sufficient to impart ≥200,000 g / mol of Mn to the hydroxyl-terminated polydisiloxane. Ideally, in unit formulas (A-III), each R M Independently an alkyl group with 1 to 6 carbon atoms, such as methyl; and each R U Independently selected from the group consisting of vinyl, allyl, and hexenyl, and the subscript e is sufficient to provide the hydroxyl-terminated polydiorganosiloxane adhesive with plasticity of 30 mils (0.76 mm) to 70 mils (1.78 mm).

[0064] Hydroxyl-terminated polydiorganosiloxane adhesives suitable for use in this invention are known in the art and can be prepared by methods such as hydrolysis and condensation of corresponding organohalosilanes or equilibration of cyclic polydiorganosiloxanes. The hydroxyl-terminated polydiorganosiloxane adhesive (A3) may comprise a single-unit polydiorganosiloxane adhesive (A-III) or a combination of two or more such polydiorganosiloxane adhesives differing in properties such as plasticity, structure, and sequence. Suitable hydroxyl-terminated polydiorganosiloxane adhesives used as component (A3) may comprise any combination of one or more of the following polydiorganosiloxanes: i) di-hydroxyl-terminated polydimethylsiloxane; ii) di-hydroxyl-terminated poly(dimethylsiloxane / methylphenylsiloxane); iii) di-hydroxyl-terminated poly(dimethylsiloxane / diphenylsiloxane); and iv) phenyl, methyl, hydroxy-methoxyloxy-terminated polydimethylsiloxane. Ideally, the hydroxyl-terminated polydimethylsiloxane adhesive (A3) comprises di-hydroxyl-terminated polydimethylsiloxane.

[0065] The hydroxyl-terminated polydiorganosiloxane adhesive (A3) is present in the curable composition at a concentration of 17.67% by weight or greater, and may be 18% by weight or greater, 19% by weight or greater, 20% by weight or greater, 21% by weight or greater, 22% by weight or greater, 22.5% by weight or greater, 23% by weight or greater, 23.5% by weight or greater, 24% by weight or greater, or even 24.5% by greater, while typically 36.2% by weight or less, and may be 36% by weight or less, 35.5% by weight or less, 35.1% by weight or more. Small, 35% by weight or less, 34.6% by weight or less, 34.5% by weight or less, 34% by weight or less, 33.5% by weight or less, 33% by weight or less, 32.5% by weight or less, 32% by weight or less, 31.5% by weight or less, 31% by weight or less, 30% by weight or less, or even 29.5% by weight or less, and ideally, 17.67% by weight to 36.2% by weight, and more ideally, 20% by weight to 30% by weight; based on the combined weight of components (A), (B), (C), (D) and (E).

[0066] Aliphatic unsaturated polydiorganosiloxane polymer (A1) and hydroxyl-terminated polydiorganosiloxane adhesive (A3) are present in an amount such that the weight ratio of the hydroxyl-terminated polydiorganosiloxane adhesive (A3) to the aliphatic unsaturated polydiorganosiloxane polymer (A1) (“A3:A1 ratio”) can be 0.89:1 or higher, and can be 1:1 or higher, 1.1:1 or higher, 1.2:1 or higher, 1.3:1 or higher, 1.5:1 or higher, 1.8:1 or higher, 2.0 The ratios are 1 or higher, 2.5 or higher, 3.0 or higher, 3.5 or higher, or even 7.2 or higher, while typically 9.33 or lower, and can be 9.0 or lower, 8.5 or lower, 8.0 or lower, 7.5 or lower, 7.3 or lower, 6 or lower, 5 or lower, 4.0 or lower, or even 3.6 or lower, and ideally, the A3:A1 ratio is in the range of 1:1 to 5:1.

[0067] The curable composition further comprises (B) a polyorganosilicon resin component (component (B)), which comprises or consists of (B1) a capped resin and (B2) an uncapped resin. The polyorganosilicon resin comprises formula R M 3SiO 1 / 2 The single functional unit (“M” unit) and the formula SiO 4 / 2 The tetrafunctional silicate unit (“Q” unit), wherein each R M As described above in Equation (AI). For example, at least one-third or at least two-thirds of RM The group is an alkyl group, such as a methyl group. The M unit can be obtained through (Me3SiO). 1 / 2 ) and (Me2PhSiO 1 / 2 For example, where Me represents methyl and Ph represents phenyl. Polyorganosilicon resins are soluble in solvents such as liquid hydrocarbons, such as benzene, toluene, xylene and heptane; or liquid organosilicon compounds, such as low-viscosity linear and cyclic polydiorganosiloxanes.

[0068] During preparation, the polyorganosilicate resin comprises the aforementioned M and Q units, and the polyorganosiloxane further comprises units having silicon-bonded hydroxyl groups and may contain the formula Si(OSiR). M 3)4 neopentylmer, in which R M As mentioned above, for example, neopentyl alcohols can be tetra(trimethylsiloxy)silanes. 29 Si NMR spectroscopy can be used to measure the hydroxyl (OH) content and molar ratio of M and Q units, where the ratio is expressed as {M(resin)} / {Q(resin)}, excluding M and Q units from the neopentyl polymer. The “M:Q ratio” represents the molar ratio of the total number of triorganosilyl groups (M units) in the resin portion of the polyorganosilicate resin to the total number of silicate groups (Q units) in the resin portion. The M:Q ratio can be from 0.5:1 to 1.5:1.

[0069] The Mn content of polyorganosilicate resins depends on a variety of factors, including the presence of R. M The type of hydrocarbon group indicated. When the peak representing the neopentyl polymer is excluded from the measurement results, the Mn of the polyorganosilicate resin refers to the number-average molecular weight measured using GPC. The Mn of the polyorganosilicate resin is from 500 g / mol to 5,000 g / mol, and can be from 2,500 g / mol to 5,000 g / mol, 2,700 g / mol to 4,900 g / mol, or 2,700 g / mol to 4,700 g / mol. A GPC test method suitable for measuring Mn is disclosed in Reference Example 1, paragraph 31, of U.S. Patent 9,593,209.

[0070] U.S. Patent 8,580,073, column 3, lines 5 through 4, line 31, and U.S. Patent Publication 2016 / 0376482, paragraphs

[0023] through

[0026] , are hereby disclosed by reference and are suitable polyorganosilicate resins for use in the hydrosilylation-curable compositions described herein. Polyorganosilicate resins can be prepared by any suitable method, such as co-hydrolysis of the corresponding silane or by silica hydrosol end-capping methods. Polyorganosilicate resins can be prepared by silica hydrosol end-capping methods, such as those disclosed in U.S. Patent 2,676,182 to Daudt et al.; U.S. Patent 4,611,042 to Rivers-Farrell et al.; and U.S. Patent 4,774,310 to Butler et al. The method described above by Daudt et al. involves reacting a silica hydrosol under acidic conditions with a hydrolyzable triorganosilane (such as trimethylchlorosilane), a siloxane (such as hexamethyldisiloxane), or a mixture thereof, and recovering the copolymer having M and Q units. The resulting copolymer typically contains 2% to 5% by weight hydroxyl groups.

[0071] Intermediates used in the preparation of polyorganosilicate resins can be triorganosilanes and silanes having four hydrolyzable substituents or alkali metal silicates. Triorganosilanes can have the formula R M 3SiX 1 , where R M As described above and X 1 The substituents represent hydrolyzable groups such as halogen, alkoxy, acyloxy, hydroxyl, oxime, or ketoxime; alternatively, halogen, alkoxy, or hydroxyl. Silanes having four hydrolyzable substituents may have the formula SiX. 2 4, where each X 2 It can be halogenated, alkoxylated, or hydroxylated. Suitable alkali metal silicates include sodium silicate.

[0072] The polyorganosilicate resins prepared as described above typically contain silicon-bonded hydroxyl groups, for example, those of the formula HOSi. 3 / 2 and / or HOR M 2SiO 1 / 2The uncapped resin (B2) contains silicon-bonded hydroxyl groups (also referred to as "silanol groups"), as measured by NMR spectroscopy. For some applications, it may be desirable for the amount of silicon-bonded hydroxyl groups to be ≤2%, forming a capped resin (B1), alternatively <0.7%, alternatively less than 0.3%, alternatively less than 1%, and alternatively 0.3% to 2%. The silicon-bonded hydroxyl groups formed during the preparation of the polyorganosilicate resin can be converted into trialkylsiloxane groups or different hydrolyzable groups by reacting the organosilicon resin with a silane, disiloxane, or disilazane containing suitable end groups in a process called capping. The silane containing the hydrolyzable groups can be added in excess molar amounts required to react with the silicon-bonded hydroxyl groups on the polyorganosilicate resin.

[0073] When the polyorganosilicate resin is the end-capping resin, the end-capping resin may contain 2% or less, and may be 0.7% or less, or 0.3% or less, and may be 0.3% to 0.8% of HOSiO 3 / 2 and / or HOR M 2SiO 1 / 2 The unit represented, where R M As described above, the concentration of silanol groups present in polyorganosiloxanes can be determined using NMR spectroscopy as described above.

[0074] End-capping resin (B1) (also referred to as "end-capping MQ resin", component (B1)) may have a unit formula (BI): (R M 3SiO 1 / 2 ) z (SiO 4 / 2 ) o Z f , where each R MAs described above in formula (AI); each Z is independently a hydrolyzable group, which may be selected from the group consisting of alkoxy, hydroxyl, or combinations thereof; and the values ​​of the subscripts z and o are such that o > 1, z > 4, and the quantity (o + z) has a value sufficient to provide the end-capping resin with 500 g / mol to <7,000 g / mol of Mn, and may be 500 g / mol or greater, 1,000 g / mol or greater, or even 2,900 g / mol or greater, while being less than 7,000 g / mol, and may be 5,000 g / mol. 1 or less, 4,700 g / mol or less, or even 4,100 g / mol or less; and the subscript f has a value sufficient to impart a hydrolyzable group content of zero to 2% to the end-capped resin, and may be zero or more, 0.3% or more, 0.7% or more, or even 0.8% or more, while being 2% or less, 1.9% or less, 1.8% or less, 1.7% or less, 1.6% or less, 1.5% or less, 1.4% or less, 1.3% or less, 1.2% or less, 1.1% or less, or even 1% or less. The percentage of hydrolyzable groups in the resin of the present invention refers to the weight percentage of hydrolyzable groups relative to the weight of the resin, as determined by Fourier Transform Infrared (FTIR) spectroscopy. Typically, each Z is a hydroxyl group (OH).

[0075] Based on the combined weight of components (A), (B), (C), (D), and (E), the end-capping resin (B1) may be present at a concentration of 0.9% by weight or greater, and may be 1% by weight or greater, 5% by weight or greater, 10% by weight or greater, 15% by weight or greater, 20% by weight or greater, 25% by weight or greater, 27% by weight or greater, 29% by weight or greater, or even 30% by weight or greater, while typically 35.9% by weight or less, and may be 35% by weight or less, 34% by weight or less, 33% by weight or less, 32% by weight or less, 31% by weight or less, or even 30.5% by weight or less.

[0076] Uncapped resin (B2) (“uncapped MQ resin”, component (B2)) may have a unitary formula (B-II): (R M 3SiO 1 / 2 ) z' (SiO 4 / 2 ) o' Z f' (B-II), where each R MAs described above in formula (AI), each Z is, for example, a hydroxyl group, and the values ​​of the subscripts z' and o' are such that o'>1, z'>4, and the quantity (o'+z') has a value sufficient to impart 500 g / mol to <7,000 g / mol of Mn to the uncapped resin, and can be 500 g / mol or more, 1,000 g / mol or more, 2,700 g / mol or more, or even 2,900 g / mol or more, while typically Less than 7,000 g / mol, and may be 5,000 g / mol or less, 4,700 g / mol or less, or even 4,300 g / mol or less; and the subscript f' has a value sufficient to impart a hydrolyzable group content greater than 3% (i.e., >3%) to the uncapped resin, and may be 3.1% or more, 3.2% or more, or even 3.4% or more, while typically 10% or less, and may be 5% or less, or even 4% or less. Ideally, in the unit formula (B-II), each R M It is an independently chosen alkyl group of 1 to 6 carbon atoms, such as methyl, each Z being OH, and the number (z+o) having a value of Mn sufficient to provide 2,900 g / mol to 5,000 g / mol for the uncapped resin.

[0077] Based on the combined weight of components (A), (B), (C), (D), and (E), the uncapped resin (B2) may be present in an amount greater than 18.53 wt% (>18.53 wt%), and may be 18.8 wt% or more, 19.0 wt% or more, 19.2 wt% or more, 19.5 wt% or more, 19.9 wt% or more, 22 wt% or more, 24 wt% or more, 24.5 wt% or more, 25 wt% or more, 28 wt% or more, 30 wt% or more, or even 32 wt% or more, while typically being 54.3 wt% or less, and may be 54 wt% or less, 53 wt% or less, 52 wt% or less, 51 wt% or less, 50 wt% or less, 49 wt% or less, 48 ​​wt% or less, 47 wt% or less, 46.5 wt% or less, or even 46.3 wt% or less.

[0078] The amount of capped and uncapped resin in the polyorganosilicate resin component may be sufficient to provide a weight ratio of uncapped resin (B2) to capped resin (B1) greater than 0.51 (>0.51), i.e., (B2):(B1) ratio, and may be 0.55 or higher, 0.6 or higher, 0.7 or higher, 0.8 or higher, 1.0 or higher, 1.2 or higher, 1.3 or higher, 1.4 or higher, 1.8 or higher, 2.0 or higher, or even 2.2 or higher, while typically 58.82 or lower, and may be 40 or lower, 30 or lower, 20 or lower, 10 or lower, 5 or lower, 4.9 or lower, or even 4.85 or lower, and ideally, the (B2):(B1) ratio is 0.55 to 5, and more ideally 0.8 to 5.0.

[0079] The polydiorganosiloxane component (A) and the polyorganosilicate resin component (B) may be present in the curable composition in an amount sufficient to provide a weight ratio of polyorganosilicate resin component (B) to polydiorganosiloxane component (A) of 1.2:1 or higher, i.e., a (B):(A) ratio or an R / P ratio, and this weight ratio may be 1.25:1 or higher, 1.28:1 or higher, 1.29:1 or higher, 1.30:1 or higher, 1.31:1 or higher, or even 1.4:1 or higher. While typically less than 1.62:1 (<1.62:1), and can be 1.60:1 or lower, 1.58:1 or lower, 1.56:1 or lower, 1.54:1 or lower, 1.53:1 or lower, 1.52:1 or lower, 1.50:1 or lower, 1.49:1 or lower, 1.45:1 or lower, 1.44:1 or lower, 1.42:1 or lower, or even 1.4:1 or lower, and ideally, the R / P ratio is 1.2:1 to 1.5:1. For example, the above R / P ratio can be the ratio of the combined weight of components (B1) and (B2) to the combined weight of components (A1) and (A3) and (A2) (if present).

[0080] The curable composition of the present invention further comprises (C) a polyorganohydrosiloxane (“SiH crosslinking agent”, component (C)). The polyorganohydrosiloxane acts as a crosslinking agent in the curable composition. Each molecule of the polyorganohydrosiloxane may have two or more, or at least three, silicon-bonded hydrogen atoms.

[0081] Polyorganohydrosiloxanes may contain the unit formula (CI):

[0082] (R M 3SiO 1 / 2 ) p (R M 2SiO 2 / 2 ) q (R M SiO3 / 2 ) r (SiO 4 / 2 ) s (R M HSiO 2 / 2 ) t (R M 2HSiO 1 / 2 ) u (CI), where R M As described above in formula (AI), and the values ​​of the subscripts p, q, r, s, t, and u such that p ≥ 0, q ≥ 0, r ≥ 0, s ≥ 0, t ≥ 0, u ≥ 0, (t + u) ≥ 2, and the quantity (p + q + r + s + t + u) is sufficient to provide a degree of polymerization of 5 to 100 or 10 to 60 for the polyorganohydrosiloxane. The degree of polymerization can be determined based on the chemical structure and / or Mn of the polyorganohydrosiloxane. Alternatively, the polyorganohydrosiloxane may comprise a unit formula (C-2):

[0083] (R M 3SiO 1 / 2 )2(R M 2SiO 2 / 2 ) aa (R M HSiO 2 / 2 ) bb (C-2),

[0084] Each R M The groups consisting of methyl and phenyl groups are selected independently, with subscripts aa ranging from 0 to 30 and subscripts bb ranging from 5 to 50.

[0085] Alternatively, the polyorganohydrosiloxane is a polyorganohydrosiloxane of formula (C-3), formula (C-4), or both (C-3) and (C-4):

[0086] R M 3SiO(R M 2SiO) g (R M HSiO) h SiR M 3 (C-3),

[0087] R M 2HSiO(R M 2SiO) i (R M HSiO) j SiR M 2H (C-4).

[0088] In equations (C-3) and (C-4) above, R MAs described above. Subscript g has an average value from 0 to 2000, subscript h has an average value from 2 to 2000, subscript i has an average value from 0 to 2000, and subscript j has an average value from 0 to 2000.

[0089] The polyorganohydrosiloxane (C) may contain 0.5% to 2% or 0.6% to 1.5% silicon-bonded hydrogen content, wherein the silicon-bonded hydrogen (SiH) content (“SiH content”) refers to the weight percentage of silicon-bonded hydrogen relative to the weight of the polyorganohydrosiloxane and can be determined using Fourier transform infrared (FTIR) spectroscopy.

[0090] Suitable polyorganohydrosiloxanes used as component (C) may include any one or more of the following polyorganohydrosiloxanes in any combination: i) bis-dimethylsiloxy-terminated poly(dimethyl / methylhydro)siloxane; ii) bis-dimethylsiloxy-terminated polymethylhydrosiloxane; iii) bis-trimethylsiloxy-terminated poly(dimethyl / methylhydro)siloxane; and iv) bis-trimethylsiloxy-terminated polymethylhydrosiloxane.

[0091] Methods for preparing polyorganohydrosiloxanes, such as the hydrolysis and condensation of organohydrohalosilanes, are well known in the art, for example, see U.S. Patent 3,957,713 to Jeram et al. and U.S. Patent 4,329,273 to Hardman et al. Polyorganohydrosiloxanes can also be prepared as described, for example, in U.S. Patent 2,823,218 to Speier et al., which discloses organohydrosiloxane oligomers and linear polymers, such as 1,1,1,3,3-pentamethyldisiloxane; bis-trimethylsiloxy-terminated polymethylhydrosiloxane homopolymers; bis-trimethylsiloxy-terminated poly(dimethyl / methylhydro)siloxane copolymers; and cyclic polymethylhydrosiloxanes. Polyorganohydrosiloxanes are also commercially available, for example, those from Gelest, Inc., Morrisville, Pennsylvania, USA, such as HMS-H271, HMS-071, HMS-993, HMS-301, HMS-301R, HMS-031, HMS-991, HMS-992, HMS-993, HMS-082, HMS-151, HMS-013, HMS-053, HAM-301, HPM-502, and HMS-HM271.

[0092] Typically, based on the combined weight of components (A), (B), (C), (D), and (E), the amount of polyorganohydrosiloxane in the curable composition may be 0.1% by weight or more, and may be 0.25% by weight or more, and may be 0.3% by weight or more, or even 0.4% by weight or more, while typically 10.0% by weight or less, and may be 5% by weight or less, 4.8% by weight or less, 4.5% by weight or less, 4.2% by weight or less, 4.1% by weight or less, 4.04% by weight or less, or even 1% by weight or less.

[0093] When relying on hydrosilylation curing processes, the ratio of silicon-bonded hydrogen to alkenyl groups in the curable composition is important. Generally, this is determined by calculating the total weight % of alkenyl groups (e.g., vinyl groups) [V] in the composition and the total weight % of silicon-bonded hydrogen [H] in the composition, and assuming the molecular weight of hydrogen is 1 and the molecular weight of vinyl is 27, the molar ratio of silicon-bonded hydrogen to vinyl is 27[H] / [V]. The aliphatic unsaturated polydiorganosiloxane component and the polyorganohydrosiloxane (C) may be sufficient to provide a curable composition in which the molar ratio of silicon-bonded hydrogen atoms to alkenyl groups is present in the curable composition of 5 or higher, 5.1 or higher, 5.5 or higher, 5.8 or higher, 6.1 or higher, 6.5 or higher, 6.8 or higher, 9 or higher, 10 or higher, 11 or higher, 12 or higher, 13 or higher, or even 14 or higher, while typically being 50 or lower, and may be 35.2 or lower, 35 or lower, 34 or lower, 30 or lower, 25 or lower, 22.5 or lower, 22 or lower, 15 or lower, or even 14.9 or lower, and ideally 10 to 30.

[0094] Based on the combined weights of components (A), (B), (C), (D), and (E), the components in the curable compositions of the present invention are present in amounts providing 0.017 wt% or more of alkenyl groups (e.g., vinyl groups) for the curable composition, and may be 0.020 wt% or more, 0.022 wt% or more, while typically 0.089 wt% or less, and may be 0.085 wt% or less, 0.08 wt% or less, 0.075 wt% or less, 0.07 wt% or less, 0.06 wt% or less, 0.05 wt% or less, 0.045 wt% or less, 0.041 wt% or less, 0.03 wt% or less, or even 0.022 wt% or less, and ideally 0.03 wt% to 0.08 wt%. The content of alkenyl groups (e.g., vinyl content) can be determined by... 29 Si NMR determination.

[0095] The curable composition of the present invention further comprises (D) a hydrosilylation catalyst (component (D)). Hydrosilylation catalysts are known in the art and are commercially available. Hydrosilylation catalysts include platinum group metal catalysts. Such hydrosilylation catalysts can be (D-1) metals selected from: platinum, rhodium, ruthenium, palladium, osmium, and iridium; alternatively, platinum, ruthenium, and iridium; and ideally, the metal is platinum. Alternatively, the hydrosilylation catalyst can be a compound of such metals (D-2), such as tris(triphenylphosphine)rhodium(I) chloride (Wilkinson's Catalyst), rhodium diphosphine chelates such as [1,2-bis(diphenylphosphine)ethane]dichlorodirhodium or [1,2-bis(diethylphosphine)ethane]dichlorodirhodium, chloroplatinic acid (Speier catalyst), chloroplatinic acid hexahydrate, or platinum dichloride. Alternatively, the hydrosilylation catalyst may be a (D-3) complex of a platinum group metal compound and an alkenyl-functionalized organopolysiloxane oligomer, or (D-4) a platinum group metal compound microencapsulated in a matrix or core-shell structure. Complexes of platinum with alkenyl-functionalized organopolysiloxane oligomers include complexes of 1,3-divinyl-1,1,3,3-tetramethyldisiloxane and platinum (Karstedt catalyst). Alternatively, the hydrosilylation catalyst may comprise a (D-5) complex microencapsulated in a resin matrix. Exemplary hydrosilylation catalysts are described in U.S. Patents 2,823,218 to Speier, 3,159,601 to Ashby, 3,220,972 to Lamoreaux, 3,296,291 to Chalk et al., 3,419,593 to Willing, 3,516,946 to Modic, and 3,715,334 to Karstedt. U.S. Patent 3,814,730; U.S. Patent 3,928,629 to Chandra; U.S. Patent 3,989,668 to Lee et al.; U.S. Patent 4,766,176 to Lee et al.; U.S. Patent 4,784,879 to Lee et al.; U.S. Patent 5,017,654 to Togashi; U.S. Patent 5,036,117 to Chung et al.; and U.S. Patent 5,175,325 to Brow; and EP 0 347 895A to Togashi et al. are described. Hydrosilylation catalysts are commercially available, for example, SYL-OFF. TMThe 4000 catalyst, SYL-OFF 4500 catalyst, and SYL-OFF 2700 catalyst are available from Dow Silicones Corporation (SYL-OFF is a trademark of Dow Silicones Corporation).

[0096] The amount of hydrosilylation catalyst used will depend on various factors, including the selection of polyorganohydrosiloxanes and aliphatic unsaturated polydiorganosiloxanes, the content of their respective silicon-bonded hydrogen atoms (SiH) and aliphatic unsaturation, and the content of platinum group metals in the selected catalyst. For example, based on the combined weight of components (A), (B), (C), (D), and (E), the amount of hydrosilylation catalyst is sufficient to catalyze the hydrosilylation reaction of SiH with aliphatic unsaturation. Alternatively, the amount of catalyst is sufficient to provide 1 part per million parts (ppm) or more, and may be 5 ppm or more, 10 ppm or more, 20 ppm or more, or even 30 ppm or more, while typically 1,000 ppm or less, and may be 500 ppm or less, 300 ppm or less, 130 ppm or less, or even 100 ppm or less of platinum group metals. Alternatively, when the hydrosilylation catalyst comprises a platinum-organosiloxane complex, the amount of the hydrosilylation catalyst may be from 0.01 wt% to 5 wt%, from 0.1 wt% to 4.0 wt%, from 0.3 wt% to 3.0 wt%, or from 0.4 wt% to 2.0 wt%, based on the combined weight of components (A), (B), (C), (D), and (E).

[0097] The curable compositions of the present invention may contain or not contain (E) a condensation reaction catalyst (component (E)). Condensation reaction catalysts are known in the art and are commercially available, such as those described in US20210277187A1. Specific examples of suitable condensation reaction catalysts include benzoic acid, acetic acid, propionic acid, citric acid, or mixtures thereof. The condensation catalyst is present in an amount sufficient to catalyze the condensation reaction of hydroxyl groups in the hydroxyl-terminated polydiorganosiloxane gum and the unterminated MQ resin. For example, based on the combined weight of components (A), (B), (C), (D), and (E), the condensation catalyst may be present at a concentration of 0.001 wt% or greater, and may be 0.01 wt% or greater, 0.03 wt% or greater, 0.05 wt% or greater, 0.08 wt% or greater, 0.09 wt% or greater, or even 0.10 wt% or greater, while typically 0.5 wt% or less, and may be 0.25 wt% or less, 0.20 wt% or less, 0.15 wt% or less, 0.13 wt% or less, 0.12 wt% or less, or even 0.11 wt% or less.

[0098] Ideally, based on the combined weight of components (A), (B), (C), (D), and (E), the curable composition of the present invention comprises 5% to 16% by weight of an aliphatic unsaturated polydiorganosiloxane polymer (A1) and 20% to 30% by weight of a hydroxyl-terminated polydiorganosiloxane adhesive (A3), wherein the content of vinyl groups (“Vi content”) in the curable composition is 0.03% to 0.08% by weight, the (B2):(B1) ratio is 0.55 to 5, and the molar ratio of silicon-bonded hydrogen atoms to vinyl groups is 10 to 30; and more ideally, the (A3):(A1) ratio is 1 to 5, and / or the R / P ratio is 1.2 to 1.5.

[0099] The curable compositions of the present invention may contain or exclude (F) a hydrosilylation reaction inhibitor (component (F)), which can be used to alter the rate of the hydrosilylation reaction compared to the reaction rate of the same composition omitting the inhibitor. Examples of suitable inhibitors include alkynols, such as 2-methyl-3-butyn-2-ol, dimethylhexynol, 3,5-dimethyl-1-hexyn-3-ol, 1-butyn-3-ol, 1-propyn-3-ol, 2-methyl-3-butyn-2-ol, 3-methyl-1-butyn-3-ol, 3-methyl-1-pentyn-3-ol, 3-phenyl-1-butyn-3-ol, 4-ethyl-1-octyyn-3-ol, 3,5-dimethyl-1-hexyn-3-ol, and 1-ethynyl-1-cyclohexanol (ETCH); silylated alkynols, such as silylated alkynols prepared by methods known in the art, for example, U.S. Patent 6,677,407 to Bilgrien et al. discloses silylating alkynols by reacting the alkynols described above with a chlorosilane in the presence of an acid acceptor; and cycloalkenylsiloxanes. Methylvinylsiloxanes, such as methylvinylsiloxanes exemplified by 1,3,5,7-tetramethyl-1,3,5,7-tetravinylcyclotetrasiloxane and 1,3,5,7-tetramethyl-1,3,5,7-tetrahexenylcyclotetrasiloxane; enyne compounds, such as 3-methyl-3-penten-1-yne and 3,5-dimethyl-3-hexen-1-yne; triazoles, such as benzotriazoles; phosphines; thiols; hydrazides; amines, such as tetramethylethylenediamine, 3-dimethylamino-1-propyne, n-methylpropynylamine, propynylamine, and 1-ethynylcyclohexylamine; fumarates, including dialkyl fumarates (such as diethyl fumarate), dialenyl fumarates (such as diallyl fumarate, dialkoxyalkyl fumarate); maleate esters, such as diallyl maleate and diethyl maleate; nitriles; ethers; or mixtures thereof. Ideally, the inhibitor is ETCH. Based on the combined weight of components (A), (B), (C), (D), and (E), the inhibitor can be present at a concentration of zero or greater, and can be greater than zero, 0.001 wt% or greater, 0.01 wt% or greater, 0.02 wt% or greater, 0.04 wt% or greater, 0.05 wt% or greater, or even 0.1 wt% or greater, while typically 5 wt% or less, and can be 1 wt% or less, 0.5 wt% or less, 0.3 wt% or less, or even 0.25 wt% or less, and can be from 0.001 wt% to 5 wt%.

[0100] The curable compositions of the present invention may or may not contain a (G) fixing additive (component (G)). Suitable fixing additives for component (G) include silane coupling agents such as methyltrimethoxysilane, vinyltrimethoxysilane, allyltrimethoxysilane, 3-methacryloyloxypropyltrimethoxysilane, 3-aminopropyltrimethoxysilane, N-(2-aminoethyl)-3-aminopropyltrimethoxysilane, bis(trimethoxysilyl)propane and bis(trimethoxysilyl)hexane; and mixtures or reaction mixtures of said silane coupling agents. Alternatively, the fixative additive may be tetramethoxysilane, tetraethoxysilane, dimethyldimethoxysilane, methylphenyldimethoxysilane, methylphenyldiethoxysilane, phenyltrimethoxysilane, methyltrimethoxysilane, methyltriethoxysilane, vinyltriethoxysilane, allyltriethoxysilane, 3-glycidoxypropyltrimethoxysilane, 3-glycidoxypropyltriethoxysilane, or 3-methacryloyloxypropyltrimethoxysilane.

[0101] Other examples of suitable immobilization additives include reaction products of vinylalkoxysilanes with epoxy-functionalized alkoxysilanes; reaction products of vinylacetoxysilanes with epoxy-functionalized alkoxysilanes; and combinations of polyorganosiloxanes having at least one aliphatic unsaturated hydrocarbon group and at least one hydrolyzable group per molecule with epoxy-functionalized alkoxysilanes (e.g., physical blends and / or reaction products) (e.g., combinations of hydroxyl-terminated vinyl-functionalized polydimethylsiloxanes with glycidoxypropyltrimethoxysilane).

[0102] Exemplary fixative additives are known in the art, such as those in U.S. Patent 9,562,149, U.S. Patent Application Publication No. 2003 / 0088042, U.S. Patent Application Publication No. 2004 / 0254274, U.S. Patent Application Publication No. 2005 / 0038188, U.S. Patent Publication No. 2012 / 0328863, paragraph

[0091] , and U.S. Patent Publication No. 2017 / 0233612, paragraph

[0041] ; and European Patent 0 556 023. Fixative additives are commercially available. For example, SYL-OFF. TM 9250, SYL-OFF9176, SYL-OFF 297, and SYL-OFF 397 are available from Dow Silicones Corporation, Midland, Michigan, USA. Other exemplary immobilizing additives include (G-1) vinyltriacetoxysilane, (G-2) glycidoxypropyltrimethoxysilane, and (G-3) combinations of (G-1) and (G-2). This combination (G-3) may be a mixture and / or a reaction product.

[0103] The amount of the fixing additive depends on various factors, including the type of substrate on which the curable composition will be applied. For example, based on the combined weight of components (A), (B), (C), (D), and (E), the fixing additive (G) can be present at a concentration of zero or greater, and can be 0.01% by weight or greater, 0.1% by weight or greater, 0.5% by weight or greater, or even 0.6% by weight or greater, while typically 5% by weight or less, and can be 4% by weight or less, 3% by weight or less, 2% by weight or less, 1.5% by weight or less, or even 1% by weight or less, and can be from 0.01% by weight to 5% by weight.

[0104] The curable composition may or may not contain an olefin reactive diluent (component (H)). The olefin reactive diluent (also referred to as "reactive diluent") comprises a hydrocarbon compound having 8 to 18 carbon atoms per molecule and at least one aliphatic unsaturation. The olefin reactive diluent may be linear. The reactive diluent may contain 12 to 16 carbon atoms or 14 to 16 carbon atoms. The reactive diluent may be linear or branched. The aliphatic unsaturation may be side-chain or terminal. A suitable reactive diluent for component (H) may be any combination of one or more of the following: (H-1) n-dodecene; (H-2) n-tetradecene; (H-3) n-hexadecene; (H-4) n-octadecene; (H-5) any branched isomer of any of (H-1), (H-2), (H-3) and / or (H-4); and (H-6) a combination of two or more of (H-1), (H-2), (H-3), (H-4) and / or (H-5). The reactive diluent may have a double bond at the terminal position. Ideally, the reactive diluent is selected from n-tetradecene, n-hexadecene, or mixtures thereof. Based on the combined weight of components (A), (B), (C), (D), and (E), the amount of the olefinic reactive diluent may be zero or more, and may be greater than zero, 0.5% or more, 0.7% or more, 1% or more, 1.2% or more, 1.5% or more, 1.75% or more, or even 1.9% or more, while typically less than 10%, and may be 8% or less, 6% or less, 4% or less, 2% or less, or even 1.8% or less.

[0105] The curable composition may or may not contain (I) a solvent (component (I)). The solvent may be an organic solvent, such as a hydrocarbon, ketone, acetate, ether, and / or a cyclic siloxane with an average degree of polymerization of 3 to 10. Suitable hydrocarbons for use as solvents may be aromatic hydrocarbons, such as benzene, toluene, or xylene; aliphatic hydrocarbons, such as hexane, heptane, octane, or isoparaffins; or combinations thereof. Ideally, the solvent may be a glycol ether, such as propylene glycol methyl ether, dipropylene glycol methyl ether, or propylene glycol n-butyl ether. Suitable ketones include acetone, methyl ethyl ketone, or methyl isobutyl ketone. Suitable acetates include ethyl acetate or isobutyl acetate. Suitable ethers include diisopropyl ether or 1,4-dioxolane. Suitable cyclic siloxanes having a degree of polymerization of 3 to 10, or 3 to 6, include hexamethylcyclotrisiloxane, octamethylcyclotetrasiloxane, and / or decamethylcyclopentasiloxane. Ideally, the solvent can be selected from benzene, toluene, xylene, heptane, ethylbenzene, ethyl acetate, or a combination of two or more of them.

[0106] The amount of solvent will depend on a variety of factors, including the type of solvent selected and the amount and type of other components chosen for the curable composition. However, based on the combined weight of all components in the curable composition, the amount of solvent can range from 0% to 90%, and can be 0% to 70%, 20% to 70%, or 30% to 70%. Solvents can be added during the preparation of the curable composition, for example, to aid in mixing and delivery of one or more of the aforementioned components. All or part of the solvent can be added together with one or more of the other components. For example, the polyorganosilicate resin can be dissolved in a solvent first, and then combined with other components in the curable composition. All or part of the solvent can optionally be removed after the preparation of the curable composition, such that the resulting curable composition will be solvent-free, i.e., will contain no solvent, or may contain trace amounts of residual solvent from the delivery of the components in the curable composition.

[0107] The curable compositions of the present invention may include or exclude a neutralizing agent (component (J)) that can be used to accelerate the condensation reaction. Suitable neutralizing agents may include silyl phosphonates, silyl phosphates, or mixtures thereof. Exemplary neutralizing agents are bis(trimethylsilyl)phosphonates, such as bis(trimethylsilyl)vinylphosphonate, bis(trimethylsilyl)phosphate, or mixtures thereof. Based on the combined weight of components (A), (B), (C), (D), and (E), the concentration of the neutralizing agent may be zero or more, and may be greater than zero, 0.001 wt% to 0.020 wt%, 0.005 wt% to 0.019 wt%, 0.01 wt% to 0.018 wt%, or 0.012 wt% to 0.017 wt%.

[0108] The present invention also relates to a method for preparing the curable composition described above. The method may include the following steps: step i) mixing a hydroxyl-terminated polydiorganosiloxane adhesive (A3), an unterminated resin (B2), and a condensation reaction catalyst (E); thereby forming a mixture, i.e., a condensation-curable formulation; and step ii) further mixing the resulting mixture obtained in step i) with an aliphatic unsaturated polydiorganosiloxane polymer (A1), a terminating resin (B1), a SiH crosslinking agent (C), and a hydrosilylation reaction catalyst (D). Optional components, such as a hydrosilylation reaction inhibitor (F), a fixing additive (G), an olefinic reactive diluent (H), a solvent (I), and / or a neutralizing agent (J), may be added in steps i), ii), or both i) and ii).

[0109] In step i) of this method, optional components, such as solvent (I) and neutralizing agent (J) (if present), are typically added before the addition of the condensation reaction catalyst (E). Step i) for example, for preparing a condensation-curable formulation, can be carried out by blending, for example, a hydroxyl-terminated polydiorganosiloxane resin (A3) and an unterminated resin (B2) at room temperature or elevated temperatures, such as 125°C to 155°C, with optional solvent (I) and / or neutralizing agent (J), followed by the addition of the condensation reaction catalyst (E), and then heating at a temperature that causes partial condensation reaction to occur, such as 125°C to 155°C or 145°C to 155°C, for 30 seconds to 30 hours. Alternatively, step i) can be carried out by a cold blending method, which involves mixing a hydroxyl-terminated polydiorganosiloxane resin (A3) and an unterminated resin (B2) with optional solvent at room temperature, followed by the addition of the condensation reaction catalyst.

[0110] After completing step i), the remaining components (i.e., the hydrosilylation-curable formulation) of the curable composition comprising the aliphatic unsaturated polydiorganosiloxane polymer (A1), the end-capping resin (B1), the SiH crosslinking agent (C), and the hydrosilylation catalyst (D) are further mixed with the mixture from step i) to form the curable composition of the present invention. Ideally, in step ii), the aliphatic unsaturated polydiorganosiloxane polymer (A1) and the end-capping resin (B1) are first mixed with the mixture obtained from step i), followed by the addition of the SiH crosslinking agent (C), and then the addition of the hydrosilylation catalyst (D). Ideally, other optional components, such as inhibitors, fixative additives, olefin reactive diluents, and solvents, may be added before the addition of the SiH crosslinking agent. Inhibitors may be added before the hydrosilylation catalyst. The mixing in steps i) and ii) of the method for preparing the curable composition can be carried out at room temperature for a sufficient time until homogeneous by conventional means.

[0111] The curable compositions described above, or curable compositions prepared by the methods described above, are suitable for forming silicone pressure-sensitive adhesives containing cured products of the curable compositions, i.e., pressure-sensitive adhesives formed by simultaneously curing the curable compositions via hydrosilylation and condensation reactions. The curable compositions of the present invention are hydrosilylation and condensation reaction curable compositions.

[0112] The present invention also relates to an adhesive article comprising a silicone pressure-sensitive adhesive residing on at least one surface of a substrate. The adhesive article can be prepared by a method comprising: (i) applying a curable composition to at least one surface of the substrate; and (ii) curing the curable composition to form a silicone pressure-sensitive adhesive (also referred to as “cured PSA”) on the surface of the substrate, thereby forming the adhesive article. The curable composition can be applied to both surfaces of the substrate. The application of the curable composition to the substrate can be carried out by any convenient means, such as a gravure coating machine, a corner roller coating machine, an offset coating machine, an offset-gravure coating machine, a roller coating machine, a reverse roller coating machine, an air knife coating machine, a slot die coating machine, or a curtain coating machine. The substrate can be any material capable of withstanding the curing conditions (described below) for curing the curable composition to form a silicone pressure-sensitive adhesive on the substrate. For example, any substrate capable of withstanding heat treatment at a temperature equal to or greater than 120 degrees Celsius (°C), optionally 150°C, is suitable. Examples of materials suitable for such substrates include polymer films and / or foams that may consist of: polyimide (PI), polyetheretherketone (PEEK), polyethylene naphthalate (PEN), liquid crystal polyacrylate, polyamide-imide (PAI), polyether sulfide (PES), polyethylene terephthalate (PET), polycarbonate (PC), polymethyl methacrylate (PMMA), thermoplastic polyurethane (TPU), thermoplastic elastomer (TPE), polyethylene (PE), or polypropylene (PP). The thickness of the substrate is not critical; however, it can range from 5 micrometers (μm) to 300 μm, alternatively from 10 μm to 200 μm. Ideally, the substrate is selected from the group consisting of PET, PE, PU, ​​PI, TPE, and TPU.

[0113] The curable composition can be cured by any conventional means, such as, for example, simultaneously via hydrosilylation and condensation, at a temperature depending on the coating line used (typically in the range of 100°C to 240°C, 110°C to 160°C, or 120°C to 150°C), for a duration sufficient to cure the curable composition. Ideally, curing can be carried out at 120°C to 160°C, and the curing time can be 1 second to 20 minutes, 2 seconds to 5 minutes, or 5 seconds to 2 minutes. The heating and curing steps described above can be carried out in an oven (e.g., an air-circulating oven or a tunnel oven), or by passing the coated film around a heated cylinder.

[0114] To improve the adhesion between the aforementioned silicone pressure-sensitive adhesive and the substrate, the method for preparing the adhesive article may optionally include treating the substrate before applying the curable composition. The substrate treatment may be carried out by any convenient means, such as applying a primer, or subjecting the substrate to corona discharge treatment, etching, or plasma treatment before applying the curable composition or silicone pressure-sensitive adhesive to the substrate.

[0115] The method of preparing the adhesive article may optionally further include (iii) applying a low-adhesion silicone protective film (“low-adhesion Si-PF”) to a silicone pressure-sensitive adhesive (obtained by curing the curable composition described above) opposite the substrate, for example, to protect the silicone pressure-sensitive adhesive before use of the adhesive article, such that the silicone pressure-sensitive adhesive is located between and in contact with the substrate and the low-adhesion silicone pressure-sensitive adhesive of the low-adhesion Si-PF (“low-adhesion PSA”). Low-adhesion Si-PF generally refers to a protective film comprising a second substrate and a low-adhesion Si-PSA, the second substrate being the same as or different from the substrate described above, the low-adhesion Si-PSA being different from the silicone pressure-sensitive adhesive of the present invention described above, and referring to a protective film having an adhesion strength of <10 g / in to stainless steel (SUS) as determined by an AR 1500 adhesion / peel tester according to ASTM D3330. Low-adhesion Si-PF can be directly laminated onto the silicone pressure-sensitive adhesive of the present invention during manufacturing processes (such as die-cut protection or masking protection applications in electronic applications). Low-adhesion Si-PSA in low-adhesion Si-PF can be prepared by curing: (a) a low-adhesion silicone PSA composition; or a mixture of (a) a low-adhesion silicone PSA composition and (b) a medium-to-high-adhesion silicone PSA composition, such that the resulting low-adhesion PSA has an adhesion to SUS of <10 g / in. "Low-adhesion silicone PSA composition" refers to a silicone PSA composition that provides a cured product with an adhesion to SUS of <10 g / in. "Medium-to-high-adhesion silicone PSA composition" refers to a silicone PSA composition that provides a cured product with an adhesion to SUS of >10 g / in. Suitable low-adhesion silicone PSA compositions may include, for example, DOWSIL. TM7626 adhesive, DOWSIL 7636 adhesive, DOWSIL 7646 adhesive, DOWSIL 7666 adhesive, DOWSIL 7647 adhesive, DOWSIL 7660 adhesive, DOWSIL 7645 adhesive, DOWSIL 7651 adhesive, or mixtures thereof. Suitable medium to high adhesion silicone PSA compositions may include, for example, DOWSIL 7652 adhesive, DOWSIL 7667 adhesive, DOWSIL 7657 adhesive, DOWSIL 7685 adhesive, DOWSIL 7663 adhesive, DOWSIL 7695 adhesive, DOWSIL 7687 adhesive, or mixtures thereof. The coating weight of the above-described low adhesion silicone PSA compositions or combinations thereof with one or more of the above-described medium to high adhesion silicone PSA compositions may be sufficient to provide a thickness of 1 μm to 100 μm, 5 μm to 50 μm, or 9 μm to 11 μm for the low adhesion Si-PSA.

[0116] The coating weight of the curable composition of the present invention is sufficient to provide a thickness of 1 μm to 100 μm, 5 μm to 50 μm, 10 μm to 20 μm, or 14 μm to 17 μm for cured PSA (i.e., silicone pressure-sensitive adhesive). The curable composition of the present invention can provide the silicone pressure-sensitive adhesive with desired adhesion properties, including, for example, adhesion to low-adhesion Si-PF ≥ 400 g / in after peeling at a speed of 300 mm / min at a 180° angle, after 20 minutes at room temperature or after aging the silicone pressure-sensitive adhesive on low-adhesion Si-PF at 70° and 80% relative humidity (RH) for 3 days; or adhesion to SUS ≥ 400 g / in (further details are provided in the peel adhesion test below). High adhesion makes the interface between the silicone pressure-sensitive adhesive and the substrate (adhesive) sufficiently strong to resist delamination after manufacturing processes (such as masking or protection).

[0117] Figure 1A partial cross-section of the adhesive article (100) is shown. The component (100) includes a silicone pressure-sensitive adhesive (Si-PSA) (102) having a surface (102a) and an opposite surface (102b). The Si-PSA (102) may be as described above for the silicone pressure-sensitive adhesive of the present invention. The opposite surface (102b) of the silicone pressure-sensitive adhesive (102) adheres to the surface (103a) of a low-adhesion silicone PSA (103) with an adhesion force of ≥400 g / in, as measured by the test methods described in the following examples. The Si-PSA (102) may have a thickness of 10 μm to 200 μm. The Si-PSA (102) adheres to a first substrate (101) having a surface (101a) and an opposite surface (101b). The surface (102a) of the Si-PSA (102) contacts the opposite surface (101b) of the first substrate (101). Si-PSA (102) is adhered to a low-adhesion Si-PSA (103) having a surface (103a) and an opposite surface (103b). The low-adhesion Si-PSA (103) may have a thickness of 10 μm to 200 μm. The opposite surface (102b) of Si-PSA (102) contacts the opposite surface (103b) of the low-adhesion Si-PSA (103). The low-adhesion Si-PSA (103) is adhered to a second substrate (104) having a surface (104a) and an opposite surface (104b). The surface (103b) of the low-adhesion Si-PSA (103) contacts the opposite surface (104a) of the second substrate (104). The low-adhesion silicone protective film (Si-PF) (200) is composed of the low-adhesion Si-PSA (103) and the second substrate (104). The low-adhesion Si-PF (200) may be as described above. As described above, the first substrate (101) and the second substrate (104) may be the same or different, and may each have a thickness of 10 μm to 200 μm independently.

[0118] Example

[0119] Some embodiments of the invention will now be described in the following examples, wherein all amounts, ratios, and percentages are by weight unless otherwise stated. Table 1 lists the materials of the curable compositions used in the samples described below. Note: “Vi” represents vinyl, “Me” represents methyl, and D represents Me₂SiO₂. 2 / 2 M OH The expression ((HO)Me2SiO) 1 / 2 The monofunctional siloxane unit of M; Vi Expression (Me2ViSiO) 1 / 2 DOWSIL monofunctional siloxane unit. TM SILASTIC TM and XIAMETERTM It is a trademark of Dow Silicones.

[0120] Table 1: Materials used as components in curable compositions

[0121]

[0122]

[0123]

[0124] *The adhesion of low-adhesion Si-PF to SUS is 1 g / in, as measured using an AR-1500 adhesion / glass tester according to ASTM D3330.

[0125] The formulations of the curable composition samples are shown in Tables 2 and 3, where the amount of each component is reported in grams (g). The curable compositions are prepared by the following steps:

[0126] Step 1): Prepare condensation-curable formulations by means of "cold blending" or "thickening". Prepare CE-A, CE-F, IE-7, and IE-8 by means of "thickening", and prepare other CE and IE by means of "cold blending" as described below.

[0127] "Thickening" method: Add (A3) OH glue, (B2) uncapped MQ resin, (I) solvent, and (J) neutralizer together to a 500 mL three-necked round-bottom reaction flask at room temperature. Stir the resulting mixture in the middle neck with a stainless steel stirrer at 250 rpm for 20 minutes, followed by the addition of (E) condensation reaction catalyst during stirring. Connect the other neck to a Dean-Stark trap, and then to a condenser with tap water cooling capability. The final neck includes a thermometer and a nitrogen purge adapter for shutting off the system. Finally, mount the three-necked flask containing the mixture to a temperature-controlled heating mantle to achieve a reaction temperature of 145°C. Allow the reaction to continue for 3 hours from reflux. Then, cool the resulting formulation to room temperature for later use.

[0128] "Cold blending" method: At room temperature, add (A3) OH glue, (B2) uncapped MQ resin, and (I) solvent together to a 500 mL three-necked round-bottom reaction flask and mix at 3500 rpm for 30 seconds until homogeneous. Then, add (E) condensation reaction catalyst and mix at 3500 rpm for 30 seconds until homogeneous. The resulting formulation is for later use.

[0129] Step 2): Add (A1)Vi polymer and (B1) end-capped MQ resin to the condensable curable formulation obtained from Step 1) above, and mix until homogeneous. Then, further add (F) inhibitor, (G) fixing additive, (H) olefinic reactive diluent and (I) solvent, and mix until homogeneous. Then, further add (C) SiH crosslinking agent, and mix until homogeneous, followed by (D) Pt catalyst, and mix in the same manner until homogeneous to obtain a curable composition sample. Mix the components in Step i) and Step ii) at 500 rpm at room temperature for 300 seconds.

[0130] The curable composition samples obtained above were applied to a 50 μm thick PET substrate. The thickness of this sample imparted a thickness of 15.5 μm ± 1.5 μm to the silicone pressure-sensitive adhesive (i.e., the cured product of the curable composition) after curing in an oven at 150°C for 2 minutes. After curing, the adhesive properties of the obtained tape samples were characterized according to the peel adhesion test described below. The characterization results are given in Tables 4 and 5 below.

[0131] Table 2: Examples of the Invention of Curable Compositions

[0132]

[0133] Table 3: Comparative Examples of Curable Compositions

[0134]

[0135] Data analysis and characterization

[0136] Peel adhesion test

[0137] Peel adhesion test was performed according to ASTM D3330.

[0138] The adhesion strength of each tape sample prepared as described above to the adhesive was tested. The adhesive was SUS and the low-adhesion Si-PF prepared above. Before use, the SUS plate was first cleaned with solvent. The tape samples obtained above were cut into 1-inch widths and then applied to the adhesive, such that the silicone pressure-sensitive adhesive came into contact with the adhesive by rolling it twice in each direction at a speed of 10 mm / s using a standard 2 kg test roller. Peel tests were performed using an AR-1500 adhesion / peel tester at a peel speed of 300 mm / min and an angle of 180°. During the peel test of the low-adhesion Si-PF adhesive, the low-adhesion Si-PF was peeled off the tape. When the peel test of the SUS adhesive was performed, the tape was peeled off the SUS. The unit is grams per inch (g / inch).

[0139] After the silicone pressure-sensitive adhesive was in contact with SUS at room temperature (RT, 25°C) for 20 minutes, the "adhesion to SUS (RT-20 minutes)" test was performed on the sample.

[0140] After the silicone pressure-sensitive adhesive was in contact with low-adhesion Si-PF for 20 minutes at RT, the "Adhesion to Si-PF (RT-20 minutes)" test was performed on the sample. After aging the sample at 70°C and 80% RH for 3 days, the "Aging Adhesion to Si-PF (70°C and 80% RH-3 days)" test was performed as above.

[0141] It is worth noting that some samples had silicone pressure-sensitive adhesives that were partially or completely transferred to the adhesive, and therefore they were reported as cohesive failure (“CF”), and some samples had adhesion values ​​that were too low to be detected under the aforementioned test conditions (i.e., below 1 g / cm² on the adhesion / peel tester). 2 (the detection limit), therefore they are reported as "NA (Not Applicable)".

[0142] Probe viscosity test

[0143] According to ASTM D2979, Polyken is used. TM The PT-1000 probe viscosity tester is used for probe testing.

[0144] Table 4 presents the characterization results for the IE samples. As shown in Table 4, all IE 1–9 curable compositions can be cured to form silicone pressure-sensitive adhesives with desired adhesive properties, including initial adhesion of ≥400 g / in to low-adhesion Si-PF after 20 minutes at RT and aged adhesion of ≥400 g / in to Si-PF after 3 days of aging at 70°C and 80% RH. Furthermore, IE 1 to 3, 5, and 7 to 9 samples also provided adhesion of ≥400 g / in to SUS.

[0145] Table 5 includes the characterization results for the CE samples. As shown in Table 5, CE-I (without Vi polymer or Vi glue), CE-A (Vi glue instead of Vi polymer), and CE-C (3.08 wt% Vi polymer) all resulted in CF during peeling from Si-PF. CE-D, containing 22.1 wt% Vi polymer and an OH glue:Vi polymer weight ratio of 0.74, resulted in adhesion to Si-PF of less than 400 g / in. CE-J, without OH glue and uncapped MQ resin, showed adhesion to Si-PF <400 g / in. CE-B, without OH glue, failed to achieve adhesion to Si-PF of 400 g / in or greater. CE-F, containing less uncapped MQ resin than claimed, and exhibiting undesirable low initial adhesion to Si-PF due to the undesirable low amount of uncapped MQ resin and / or a low uncapped / capped MQ resin ratio of 0.51, showed low adhesion to Si-PF. CE-E, without capped MQ resin, showed low adhesion to Si-PF. CE-G and CE-H samples, which have R / P ratios outside the claimed protection range, showed adhesion to Si-PF <400 g / in and cohesive failure, respectively.

[0146] Table 4: Characterization results of IE-1 to IE-9 samples

[0147]

[0148] The weight % value is relative to the total weight of components (A), (B), (C), (D), and (E).

[0149] Table 5: Characterization results of CE-A to CE-J samples

[0150]

[0151] The weight % value is relative to the total weight of components (A), (B), (C), (D), and (E).

Claims

1. A curable composition, said curable composition comprising: (A) A polydiorganosiloxane component, wherein the polydiorganosiloxane component comprises: (A1) Greater than 3.1% to 20% by weight of aliphatic unsaturated polydiorganosiloxane polymers of formula (AI): R M (3-c) R U c SiO-(R U R M SiO) a -(R M 2SiO) b -SiR U d R M (3-d) (A-I) Each R M Each R is independently selected from groups consisting of monovalent hydrocarbon groups of 1 to 30 carbon atoms without aliphatic unsaturation and monovalent halohydrocarbon groups without aliphatic unsaturation. U Independently an alkenyl group, and the average of the subscripts a, b, c, and d such that a ≥ 0, b > 0, c is zero or 1, d is zero or 1, the number (a + b) is from 100 to 2000, and the number (a + c + d) ≥ 2; and (A3) Hydroxyl-terminated polydiorganosiloxane adhesives of unit formula (A-III): {(HO)R M 2SiO 1 / 2 }2(R M 2SiO 2 / 2 ) e (A-III) Each R M Independently selected from the group consisting of monovalent hydrocarbon groups of 1 to 30 carbon atoms without aliphatic unsaturation and monovalent halohydrocarbon groups without aliphatic unsaturation; and the subscript e having a value sufficient to impart a plasticity of 20 mils (0.51 mm) to 80 mils (2.03 mm) to the hydroxyl-terminated polydiorganosiloxane adhesive (A3), wherein the plasticity is measured based on ASTM D926 by applying a 1 kg load to a 4.2 g spherical sample at 25 °C for 3 minutes, and the result is measured in thousandths of an inch (mil), and the procedure is based on ASTM D926; it is present in an amount providing a weight ratio of 0.89:1 to 9.33:1 of the hydroxyl-terminated polydiorganosiloxane adhesive (A3) to the aliphatic unsaturated polydiorganosiloxane polymer (A1); (B) A polyorganosilicate resin component, wherein the polyorganosilicate resin component comprises: (B1) Unitary (BI) end-capping resin: (R M 3SiO 1 / 2 ) z (SiO 4 / 2 ) o Z f , where each R M The group is independently selected from the group consisting of monovalent hydrocarbon groups of 1 to 30 carbon atoms without aliphatic unsaturation and monovalent halohydrocarbon groups without aliphatic unsaturation, each Z being independently a hydrolyzable group, the subscript f being zero to a value sufficient to impart at most 2% hydrolyzable group content to the end-capping resin, and the values ​​of the subscripts z and o such that o > 1, z > 4, and the quantity (o + z) having a number average molecular weight value sufficient to provide the end-capping resin with 500 g / mol to < 7,000 g / mol; (B2) More than 18.53% to 54.3% by weight of uncapped monomeric (B-II) resins: (R M 3SiO 1 / 2 ) z' (SiO 4 / 2 ) o' Z f' , where each R M The uncapped resin is independently selected from a group consisting of monovalent hydrocarbon groups of 1 to 30 carbon atoms without aliphatic unsaturation and monovalent halohydrocarbon groups without aliphatic unsaturation, each Z being an independently hydrolyzable group, the subscript f' having a value sufficient to impart a hydrolyzable group content greater than 3% to 10%, and the subscripts z' and o' having values ​​such that o' > 1, z' > 4, and the quantity (o' + z') having a number average molecular weight value sufficient to provide the uncapped resin with 500 g / mol to < 7,000 g / mol; The weight ratio of the uncapped resin (B2) to the capped resin (B1) is greater than 0.51 to 58.

82. The polydiorganosiloxane component (A) and the polyorganosilicate resin component (B) are present in an amount providing a weight ratio of the polyorganosilicate resin component (B) to the polydiorganosiloxane component (A) of 1.2:1 to less than 1.62:

1. (C) Monomeric (CI) polyorganohydrosiloxanes: (R M 3SiO 1 / 2 ) p (R M 2SiO 2 / 2 ) q (R M SiO 3 / 2 ) r (SiO 4 / 2 ) s (R M HSiO 2 / 2 ) t (R M 2HSiO 1 / 2 ) u (C-I), Each R M The polyorganohydrosiloxane is independently selected from the group consisting of monovalent hydrocarbon groups of 1 to 30 carbon atoms without aliphatic unsaturation and monovalent halohydrocarbon groups without aliphatic unsaturation; and the values ​​of the subscripts p, q, r, s, t, and u are such that p ≥ 0, q ≥ 0, r ≥ 0, s ≥ 0, t ≥ 0, u ≥ 0, (t + u) ≥ 2, and the quantity (p + q + r + s + t + u) is sufficient to provide the polyorganohydrosiloxane with a degree of polymerization of 5 to 100; it exists in an amount providing the curable composition with a molar ratio of 5 to 50 of silicon-bonded hydrogen atoms to alkenyl groups; (D) A hydrosilylation catalyst, said hydrosilylation catalyst being sufficient to provide 1 ppm to 1000 ppm of platinum group metals; and (E) Condensation reaction catalyst; The content of alkenyl groups in the curable composition is in the range of 0.017% by weight to 0.089% by weight; The weight percentage is relative to the combined weight of components (A), (B), (C), (D), and (E).

2. The curable composition according to claim 1, wherein the curable composition further comprises (F) 0.001 wt% to 5 wt% of a hydrosilylation reaction inhibitor and (G) 0.01 wt% to 5 wt% of a fixation additive or a mixture thereof, wherein the weight percentages are based on the combined weight of components (A), (B), (C), (D) and (E).

3. The curable composition according to claim 1, wherein, In equation (AI), each R M Alkyl groups independently selected from 1 to 6 carbon atoms; each R U Independently selected from the group consisting of vinyl, allyl, and hexenyl; and the quantity (a + b) is sufficient to impart 300 mPa to the aliphatic unsaturated polydiorganosiloxane polymer. 100,000 millipascals per second The viscosity value per second.

4. The curable composition according to claim 1, wherein, In the unitary form (A-III), each R M An alkyl group consisting independently of 1 to 6 carbon atoms; and the subscript e is sufficient to provide the hydroxyl-terminated polydiorganosiloxane adhesive with 30 mils (0.76 mm) to 70 mils (1.78 mm) of plasticity.

5. The curable composition according to claim 1, wherein, In the unitary form (B-II), each R M The alkyl groups are independently 1 to 6 carbon atoms, each Z being OH, and the number (z'+ o') is sufficient to provide the uncapped resin (B2) with a number-average molecular weight of 2,900 g / mol to 5,000 g / mol.

6. The curable composition according to claim 1, wherein the hydroxyl-terminated polydiorganosiloxane adhesive (A3) is present at a concentration of 17.67% by weight to 36.2% by weight based on the combined weight of components (A), (B), (C), (D) and (E).

7. The curable composition according to claim 1, wherein the polydiorganosiloxane component (A) comprises 5% to 16% by weight of the aliphatic unsaturated polydiorganosiloxane polymer (A1) and 20% to 30% by weight of the hydroxyl-terminated polydiorganosiloxane adhesive (A3), wherein the weight percentages are relative to the combined weight of components (A), (B), (C), (D), and (E); the content of vinyl groups in the curable composition is 0.03% to 0.08% by weight; the weight ratio of the unterminated resin (B2) to the terminated resin (B1) is 0.55 to 5; and the molar ratio of silicon-bonded hydrogen atoms to vinyl groups is 10 to 30.

8. A method for preparing a curable composition according to any one of claims 1 to 7, the method comprising: i) Mix the hydroxyl-terminated polydiorganosiloxane sealant (A3), the unterminated resin (B2), and the condensation reaction catalyst (E); as well as ii) Further mix the resulting mixture obtained from step i) with the aliphatic unsaturated polydiorganosiloxane polymer (A1), the end-capping resin (B1), the polyorganohydrosiloxane (C) and the hydrosilylation catalyst (D); thereby forming the curable composition.

9. An adhesive article comprising a substrate and a silicone pressure-sensitive adhesive on at least one surface of the substrate, wherein the silicone pressure-sensitive adhesive is a cured product of a curable composition according to any one of claims 1 to 7.

10. A method for preparing an adhesive article, the method comprising: Optionally (1) the surface of the substrate is treated. (2) Applying the curable composition according to any one of claims 1 to 7 to at least one surface of the substrate, and (3) Curing the curable composition.

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