KR20200075002A - 1-component curable silicone composition - Google Patents

Abstract

The present invention relates to a one-component curable silicone composition, comprising: (A) an organopolysiloxane having two or more silicon-bonded alkenyl groups per molecule; (B) an organohydrogenpolysiloxane having two or more silicon-bonded hydrogen atoms per molecule; (C) a platinum group metal-based hydrosilylation catalyst; (D) inhibitors of hydrosilylation reactions; And (E) acrylic and/or methacrylic compounds. The one-component curable silicone composition exhibits excellent storage stability, and can be cured at a relatively low temperature to form a cured product having excellent adhesion to various substrates.

Description

1-component curable silicone composition

Cross-reference to related applications

This application claims priority to U.S. Patent Application No. 62/587226 filed November 16, 2017 and all of its advantages, the content of which is incorporated herein by reference.

Technology field

The present invention relates to a one-component curable silicone composition capable of curing at a relatively low temperature to form a cured product having excellent adhesion to various substrates.

The hydrosilylation-curable silicone compositions form cured products with excellent properties such as weatherability and heat resistance, which harden particularly quickly by heating without generating by-products upon curing, so such compositions are used in electrical/electronic devices It is used as an adhesive, sealant or coating agent.

Examples of such curable silicone compositions include organopolysiloxanes having two or more silicon-bonded alkenyl groups per molecule, organohydrogenpolysiloxanes having two or more silicon-bonded hydrogen atoms per molecule, hydrosilylation reaction catalysts, allyl ester compounds , A curable silicone composition comprising a nitrile compound and an adhesion promoter (see Patent Document 1); Curable silicone composition comprising an organopolysiloxane having two or more alkenyl groups per molecule, an organopolysiloxane having two or more silicon-bonded hydrogen atoms per molecule, a hydrosilylation reaction catalyst, and an acid anhydride having a silicon-bonded alkoxy group ( Patent Document 2); And an organopolysiloxane having two or more alkenyl groups per molecule, an organopolysiloxane resin comprising R ₃ SiO _1/2 units and SiO _4/2 units at a molar ratio of R ₃ SiO _1/2 /SiO _4/2 of 0.6 to 1.0 Wherein each R is independently an aliphatic unsaturated-free C ₁ -C ₁₀ monovalent hydrocarbon group or a C ₂ -C ₆ alkenyl group), an organohydrogenpolysiloxane having 3 or more silicon-bonded hydrogen atoms per molecule And a curable silicone composition comprising a platinum group metal-based catalyst (see Patent Document 3).

Such a curable silicone composition is provided in two components divided into an organopolysiloxane having silicon-bonded hydrogen atoms and a hydrosilylation reaction catalyst to ensure storage stability. For use, the two ingredients must be uniformly mixed. As a result, if the mixing ratio of the two components should be changed or if the two components are not sufficiently mixed, the original performance will not be sufficiently exhibited.

On the other hand, in general, such a curable silicone composition is cured at a high temperature such as 100° C. or higher so as to cure sufficiently to form a cured product having excellent adhesion to a substrate. Therefore, the curable silicone composition cannot be cured sufficiently at a low temperature such as 80° C. or less, and even if cured, the cured product cannot sufficiently adhere to the substrate.

Therefore, even if the curable silicone composition described in each of Patent Documents 1 to 3 is in a one-component form, it is difficult to achieve excellent adhesion of a cured product to various substrates and excellent storage stability in a one-component form.

Patent Document 1: Japanese Patent Application Publication No. 2009-221312 A Patent Document 3: US Patent Application Publication No. 2012/0309921 A1 Patent Document 3: US Patent Application Publication No. 2016/0053148 A1

An object of the present invention is to provide a one-component curable silicone composition that forms a cured product that exhibits excellent storage stability and exhibits excellent adhesion to various substrates by curing at relatively low temperatures.

The one-component curable silicone composition of the present invention,

(A) an organopolysiloxane having two or more silicon-bonded alkenyl groups per molecule;

(B) an organohydrogenpolysiloxane having two or more silicon-bonded hydrogen atoms per molecule, the content of silicon-bonded hydrogen atoms being at least 1% by mass of component (B), and silicon-bonding in component (B) The organohydrogenpolysiloxane in an amount such that the content of the hydrogen atom is 0.1 to 10 mol per mol of the silicon-bonded alkenyl group in component (A);

(C) a platinum group metal-based hydrosilylation catalyst, wherein the platinum group metal-based hydrosilylation catalyst in an amount of 1 to 200 ppm of the platinum group metal in component (C) in mass units for the composition;

(D) a hydrosilylation reaction inhibitor in an amount of 0.1 to 1% by mass of the composition; And

(E) acrylic and/or methacrylic compounds in an amount of 0.1 to 5% by mass of the composition.

Component (A) is preferably

(A-1) is a straight chain organopolysiloxane having two or more silicon-bonded alkenyl groups per molecule;

(A-2) An organopolysiloxane resin composed of R ¹ ₃ SiO _1/2 units and SiO _4/2 units, wherein the molar ratio of (R ¹ ₃ SiO _1/2 units)/(SiO _4/2 units) is 0.6 to 1.7 And each R ¹ represents a monovalent hydrocarbon group having 1 to 12 carbon atoms, but two or more R ¹ per molecule is an alkenyl group having 2 to 12 carbon atoms, the organopolysiloxane resin; or

It is a mixture of component (A-1) and component (A-2),

More preferably, it is a mixture of component (A-1) and component (A-2), and the content of component (A-1) is 10 mass% or more of the mixture of component (A-1) and component (A-2) to be.

Component (D) preferably comprises acetylene alcohol and unsaturated carboxylic esters.

Component (E) is preferably 3-methacryloxypropyl trimethoxysilane, 3-methacryloxypropyl triethoxysilane or methyl methacrylate.

The one-component curable silicone composition of the present invention is preferably an adhesive, sealant or coating agent for electrical/electronic devices.

The one-component curable silicone composition according to the present invention exhibits excellent storage stability and can form a cured product exhibiting excellent adhesion to various substrates by curing at relatively low temperatures.

<One-component curable silicone composition>

The one-component curable silicone composition according to the present invention includes the above components (A) to (E). Such a one-component curable silicone composition exhibits excellent storage stability and can form a cured product exhibiting excellent adhesion to a substrate contacted during curing by curing at low temperatures, such as 80° C. or less. Each of the ingredients will be described in detail below.

Component (A) is an organopolysiloxane having two or more silicon-bonded alkenyl groups per molecule. Examples of alkenyl groups include alkenyl groups having 2 to 12 carbon atoms, such as vinyl groups, allyl groups, butenyl groups, pentenyl groups, hexenyl groups, heptenyl groups, octenyl groups, nonenyl groups, de Senyl groups, undecenyl groups and dodecenyl groups are included, of which vinyl groups are preferred. In addition, examples of the group that binds to the silicon atom in addition to the alkenyl group in component (A) include alkyl groups having 1 to 12 carbon atoms, such as methyl group, ethyl group, propyl group, isopropyl group, butyl group, Isobutyl group, tert-butyl group, pentyl group, neopentyl group, hexyl group, cyclohexyl group, heptyl group, octyl group, nonyl group, decyl group, undecyl group, and dodecyl group; Aryl groups having 6 to 20 carbon atoms, such as phenyl groups, tolyl groups, xylyl groups, and naphthyl groups; Aralkyl groups having 7 to 20 carbon atoms, such as benzyl groups, phenethyl groups, and phenylpropyl groups; And groups in which some or all of the hydrogen atoms of these groups are substituted with halogen atoms such as fluorine atoms, chlorine atoms, or bromine atoms. Furthermore, the silicon atom in component (A) can have a small amount of hydroxyl or alkoxy groups, for example methoxy or ethoxy groups, within the scope of not impairing the object of the present invention.

Examples of the molecular structure of component (A) include a straight chain structure, a partially branched straight chain structure, a branched chain structure, a cyclic structure, and a three-dimensional reticular structure. Component (A) may be one organopolysiloxane having such a molecular structure, or may be a mixture of two or more organopolysiloxanes having such a molecular structure.

Such component (A) is preferably (A-1) a straight chain organopolysiloxane; (A-2) organopolysiloxane resin; Or a mixture of component (A-1) and component (A-2).

Examples of such component (A-1) include dimethylpolysiloxane capped with dimethylvinylsiloxy groups at both molecular ends, dimethylsiloxane-methylvinylsiloxane copolymer capped with dimethylvinylsiloxy groups at both molecular ends, both molecules Dimethylsiloxane-methylphenylsiloxane copolymer capped with dimethylvinylsiloxy groups at the ends, methylphenylpolysiloxane capped with dimethylvinylsiloxy groups at both molecular ends, dimethylsiloxane-methyl capped with trimethylsiloxy groups at both molecular ends Vinylsiloxane copolymer, dimethylsiloxane-methylvinylsiloxane-methylphenylsiloxane copolymer capped with trimethylsiloxy groups at both molecular ends, dimethylpolysiloxane capped with dimethylvinylsiloxy groups at both molecular ends and die at one molecular end A mixture of dimethylpolysiloxane capped with methylvinylsiloxy groups and with dimethylhydroxysiloxy groups at the other molecular ends, dimethylpolysiloxane capped with dimethylvinylsiloxy groups at both molecular ends and dimethylhydroxysiloxane at both molecular ends. Mixtures of dimethylpolysiloxane capped with time groups, and mixtures of two or more thereof.

Component (A-2) is an organopolysiloxane resin composed of R ¹ ₃ SiO _1/2 units and SiO _4/2 units. In the above formula, each R ¹ represents a monovalent hydrocarbon group having 1 to 12 carbon atoms. The monovalent hydrocarbon group is a methyl group, ethyl group, propyl group, or similar alkyl group; Vinyl groups, allyl groups, butenyl groups, pentenyl groups, hexenyl groups, or similar alkenyl groups; Phenyl group, tolyl group, xylyl group, or similar aryl group; Benzyl groups, phenethyl groups, or similar aralkyl groups; And 3-chloropropyl groups, 3,3,3-trifluoropropyl groups, or similar halogenated alkyl groups. However, two or more R ¹ per molecule is an alkenyl group. Component (A-2) can have residual silanol groups resulting from hydrolysis of the reactive silane used to prepare component (A-2).

The molar ratio of R ¹ ₃ SiO _1/2 units to SiO _4/2 units in component (A-2) is within the range of 0.6 to 1.7, preferably within the range of 0.6 to 1.5. This is because when the molar ratio is more than the lower limit of the above-mentioned range, solubility of other components of this component is improved, and when the molar ratio is less than or equal to the upper limit of the above-mentioned range, the mechanical properties of the cured product are improved.

When a mixture of component (A-1) and component (A-2) is used as component (A), the content of component (A-1) is preferably a component ( It is 10 mass% or more or 40 mass% or more of the total amount of A-1) and component (A-2). In addition, the content of the component (A-1) is preferably 90% by mass or less of the total amount of the component (A-1) and the component (A-2) from the viewpoint of excellent mechanical properties of the cured product.

Component (B) is an organohydrogenpolysiloxane having two or more silicon-bonded hydrogen atoms per molecule, wherein the content of silicon-bonded hydrogen atoms is at least 1% by mass of this component. This is because when the content of the silicon-bonded hydrogen atom is more than the lower limit of the above-mentioned range, the curability of the present composition is improved. Examples of groups that bind to silicon atoms other than hydrogen atoms in component (B) include alkyl groups having 1 to 12 carbon atoms, such as methyl groups, ethyl groups, propyl groups, isopropyl groups, butyl groups, isobutyl groups , tert-butyl group, pentyl group, neopentyl group, hexyl group, cyclohexyl group, heptyl group, octyl group, nonyl group, decyl group, undecyl group, and dodecyl group; Aryl groups having 6 to 20 carbon atoms, such as phenyl groups, tolyl groups, xylyl groups, and naphthyl groups; Aralkyl groups having 7 to 20 carbon atoms, such as benzyl groups, phenethyl groups, and phenylpropyl groups; And groups in which some or all of the hydrogen atoms of these groups are substituted with halogen atoms such as fluorine atoms, chlorine atoms, or bromine atoms. Furthermore, the silicon atom in component (B) can have a small amount of hydroxyl or alkoxy groups, for example methoxy or ethoxy groups, within the scope of not impairing the object of the present invention.

Examples of the molecular structure of component (B) include straight chain, partially branched straight chain, branched chain, cyclic, and three-dimensional network structures, and the molecular structure is preferably a partially branched straight chain, branched chain, or three-dimensional network structure to be.

Examples of such component (B) include methylhydrogenpolysiloxane capped with trimethylsiloxy groups at both molecular ends, dimethylsiloxane-methylhydrogensiloxane copolymer capped with trimethylsiloxy groups at both molecular ends, at both molecular ends Dimethylpolysiloxane capped with dimethylhydrogensiloxy groups, dimethylsiloxane-methylhydrogensiloxane copolymer capped with dimethylhydrogensiloxy groups at both molecular ends, methylhydro capped with trimethylsiloxy groups at both molecular ends Gensiloxane-diphenylsiloxane copolymer, methylhydrogensiloxane-diphenylsiloxane-dimethylsiloxane copolymer capped with trimethylsiloxy groups at both molecular ends, (CH ₃ ) ₂ HSiO _1/2 units and SiO _4/2 Copolymers consisting of units, (CH ₃ ) ₂ HSiO _1/2 units, SiO _4/2 units and (C ₆ H ₅ )SiO _3/2 units, and mixtures of two or more thereof.

The content of component (B) is such that the content of silicon-bonded hydrogen atoms in this component is 0.1 to 10 moles, preferably 0.5 to 5 moles per mole of silicon-bonded alkenyl groups in component (A). This is because the mechanical properties of the cured product are excellent when the content of the component (B) is less than or equal to the upper limit of the above-mentioned range, whereas the curability of the composition is excellent when the content of the component (B) is more than or equal to the lower limit of the above-mentioned range.

Component (C) is a platinum group metal-based hydrosilylation catalyst used to accelerate curing of the composition. Examples of component (C) include platinum group element catalysts and platinum group element compound catalysts, and specific examples include platinum-based catalysts, rhodium-based catalysts, palladium-based catalysts, and combinations of two or more thereof. In particular, platinum-based catalysts are preferred in that curing of the composition can be dramatically accelerated. Examples of these platinum-based catalysts include micronized platinum; Platinum black; Chloroplatinic acid, alcohol-modified chloroplatinic acid; Chloroplatinic acid/diolefin complex; Platinum/olefin complexes; Platinum/carbonyl complexes such as platinum bis (acetoacetate), and platinum bis (acetylacetonate); Chloroplatinic acid/alkenylsiloxane complexes, such as chloroplatinic acid/divinyltetramethyl disiloxane complex, and chloroplatinic acid/tetravinyl tetramethyl cyclotetrasiloxane complex; Platinum/alkenylsiloxane complexes, such as platinum/divinyltetramethyl disiloxane complexes, and platinum/tetravinyl tetramethyl cyclotetrasiloxane complexes; A complex of chloroplatinic acid and acetylene alcohol; And mixtures of two or more thereof. In particular, platinum-alkenylsiloxane complexes are preferred in that curing of the composition can be accelerated.

Examples of alkenylsiloxanes used in platinum-alkenylsiloxane complexes include 1,3-divinyl-1,1,3,3-tetramethyldisiloxane, 1,3,5,7-tetramethyl-1,3, 5,7-tetravinylcyclotetrasiloxane, alkenylsiloxane oligomers (some of the methyl groups of these alkenylsiloxanes are substituted with ethyl groups, phenyl groups, etc.), and alkenylsiloxane oligomers (the vinyl groups of these alkenylsiloxanes are allyl Group, hexenyl group, and the like). In particular, 1,3-divinyl-1,1,3,3-tetramethyldisiloxane is preferred from the viewpoint of good stability of the resulting platinum-alkenylsiloxane complex.

In order to improve the stability of platinum-alkenylsiloxane complexes, these platinum-alkenylsiloxane complexes may be alkenylsiloxane oligomers, for example 1,3-divinyl-1,1,3,3-tetramethyldisiloxane, 1 ,3-diallyl-1,1,3,3-tetramethyldisiloxane, 1,3-divinyl-1,3-dimethyl-1,3-diphenyldisiloxane, 1,3-divinyl-1 ,1,3,3-tetraphenyldisiloxane, or 1,3,5,7-tetramethyl-1,3,5,7-tetravinylcyclotetrasiloxane or organosiloxane oligomers, such as dimethylsiloxane oligomers It is preferable to dissolve, and it is particularly preferable to dissolve the complex in an alkenylsiloxane oligomer.

The content of component (C) is the amount in which the platinum group metal in this component is 1 to 200 ppm in mass units for this composition. Specifically, this content is such that the content of the platinum group metal in component (C) is preferably in the range of 0.01 to 150 ppm, in the range of 0.01 to 100 ppm, or in the range of 0.1 to 100 ppm in mass units for the composition. It is a sheep. This is because the colorability of the cured product is suppressed when the content of the component (C) is excellent in the curability of the composition when the content of the component (C) is higher than or equal to the lower limit of the aforementioned range.

To extend the pot life at ambient temperature and improve storage stability, component (D) is a hydrosilylation reaction inhibitor. Examples of component (D) include acetylene alcohol, such as 1-ethynyl-cyclohexane-1-ol, 2-methyl-3-butyn-2-ol, 2-phenyl-3-butyn-2-ol, 2-e Thynyl-isopropan-2-ol, 2-ethynyl-butan-2-ol and 3,5-dimethyl-1-hexyn-3-ol; Silylated acetylene alcohols, such as trimethyl (3,5-dimethyl-1-hexyn-3-oxy) silane, dimethyl bis(3-methyl-1-butyne-oxy) silane, methylvinyl bis(3-methyl- 1-butyn-3-oxy) silane and ((1,1-dimethyl-2-propynyl)oxy)trimethylsilane; Unsaturated carboxylic acid esters such as diallyl maleate, dimethyl maleate, diethyl fumarate, diallyl fumarate and bis(2-methoxy-1-methylethyl) maleate, mono-octylmaleate, mono- Isooctylmaleate, mono-allyl maleate, mono-methyl maleate, mono-ethyl fumarate, mono-allyl fumarate and 2-methoxy-1-methylethyl maleate; En-phosphorus compounds, such as 2-isobutyl-1-butene-3-yne, 3,5-dimethyl-3-hexene-1-yne, 3-methyl-3-pentene-1-yne, 3-methyl- 3-hexene-1-yne, 1-ethynyl cyclohexene, 3-ethyl-3-butene-1-yne and 3-phenyl-3-butene-1-yne; And mixtures of two or more thereof. In particular, a mixture of acetylene alcohol and unsaturated carboxylic acid ester is preferred to prevent surface wrinkles from forming on the cured product.

The content of component (D) is in the amount of 0.1 to 1000 ppm of this component in mass units for this composition. Specifically, this content is preferably an amount of 1 to 1000 ppm or 10 to 500 ppm of this component in mass units for the composition. This is because the storage stability of the present composition is excellent when the content of the component (D) is more than the lower limit of the above-mentioned range, while the curability at low temperature of the composition is excellent when the content of the component (D) is less than or equal to the upper limit of the above-mentioned range. to be.

Component (E) is an acrylic and/or methacrylic compound to improve adhesion to various substrates that the composition will come into contact with during curing at low temperatures. Examples of such component (E) include silane compounds containing acrylic and/or methacryl groups, such as 3-methacryloxypropyl trimethoxysilane, 3-methacryloxypropyl methyldimethoxysilane, 3-methacryloxypropyl Triethoxysilane; And acrylic and/or methacryl monomers such as methyl acrylate, ethyl acrylate, methyl methacrylate. Particularly, 3-methacryloxypropyl trimethoxysilane, 3-methacryloxypropyl triethoxysilane and methyl methacrylate are preferable in terms of excellent adhesion to various engineering plastics.

The content of component (E) is in the amount of 0.1 to 5 mass% of the composition, preferably in the range of 0.1 to 3 mass% or 0.5 to 3 mass% of the composition. This is because the adhesiveness of the cured product is excellent when the content of the component (E) is more than the lower limit of the above-mentioned range, whereas the curability at low temperature of the composition is excellent when the content of the component (E) is less than or equal to the upper limit of the above-mentioned range. .

Typical additives include, but are not limited to, fillers, pigments, dyes, flame retardants, and heat and/or ultraviolet light stabilizers to improve the physical properties of the cured product.

The one-component curable silicone composition of the present invention can be prepared by combining all components at ambient temperature. Any mixing technique and apparatus described in the prior art can be used for this purpose. The specific device used will be determined by the viscosity of the final curable composition and ingredients. In order to avoid premature curing, it may be desirable to cool the ingredients during mixing.

The one-component curable silicone composition of the present invention is particularly useful as an adhesive, sealant or coating agent for electric/electronic devices sensitive to heating.

Example

Now, the one-component curable silicone composition of the present invention will be described using Examples and Comparative Examples. In the formula, Me and Vi represent a methyl group and a vinyl group, respectively. Note that the viscosity is a value obtained at 25°C. The properties of the one-component curable silicone composition were evaluated as follows.

<viscosity>

Viscosity is measured using a rotary viscometer, such as a Brookfield synchro-lectric viscometer or Wells-Brookfield 52 cone/plate viscometer. Since virtually all measured materials are virtually non-Newtonian, no correlation should be expected between results obtained using different spindles (cones) or velocities. Results are generally reported in centipoise. Viscosity was measured at 0.5 and 5.0 rpm for 2 minutes. This method is based on ASTM D 4287 for cones/plates.

<Curing conditions>

Curing conditions for the low temperature curable silicone adhesive are basically applied by using 80° C. for 1 hour in an oven.

<DSC Tc>

Differential Scanning Calorimetry (DSC) is a technique for studying the thermal behavior of materials when they undergo physical and chemical changes during heating or cooling or in isothermal mode. The results are reported in the form of an annotated thermogram with features identified by the analyst. For DSC instruments, the amount of heat flow or enthalpy change associated with the transition can be measured through calibration with different acceptable sources.

<Hardness of hardened product>

A 6 mm thick cured product was obtained by curing the low temperature-curable silicone composition at 80° C. in an oven for 1 hour. Subsequently, the hardness of the cured product was measured using Shore A hardness according to ASTM D 2240 "Standard Test Method for Rubber Property-Durometer Hardness".

<MDR>

The rheological and curing properties of the vulcanized elastomeric material are determined using a Monsanto moving die rheometer. The torque required for the lower die to vibrate through a small arc is measured. The displaced torque s'increases as the elastomer vulcanizes and is automatically plotted and/or calculated as pound-inch versus time through pre-set computerized conditions. The curve is a function of the test temperature and the characteristics of the cured and uncured elastomer, plasticity, scorch time, durometer, cure rate and modulus. The device can also measure non-displaced torque (s") (loss modulus) and calculate the tan delta (r's/s' ratio). The temperature setting for MDR measurement was applied at 80° C. for 1 hour, and observation of the curing curve was confirmed hourly. This method is based on ASTM D 5289-92.

<Pot life>

Pot life is described as the time required for the system to double its viscosity after catalysis. This is considered normal available working time. This test is designed for any material that will cure at room temperature where viscosity measurements can be made. If a minimum time is specified,'pass/fail' results may be reported. The cure rate is described as the time required to reach the specified viscosity. The pot life index can be reported by dividing the defined final viscosity by the original viscosity. Other reporting modes can be defined. For pot life measurement, a Brookfield viscometer was used with 52 cone plates. This procedure is based on ASTM D 1824.

<surface wrinkle>

Surface wrinkles are identified by visible wrinkles on the cured adhesive samples, and curing conditions for the low temperature curable silicone adhesive are basically applied using 80° C. for 1 hour in an oven.

<overlapping shear strength>

The adhesion properties of the primer, adhesive and/or sealant are determined by measuring the amount of pull required to separate the double laminate by shearing. Results are reported in pounds per square inch, unless otherwise specified. The amount of adhesive or cohesive failure is assessed by inspection of the exposed surface of the substrate. This procedure is based on ASTM D 816. Overlap shear test specimens were prepared using an Al plate, and the samples were cured at 80° C. for 1 hour in an oven.

<Adhesive destruction mode-aggregation destruction>

The adhesion of the uncured or low-strength material to the substrate is determined by making a sandwich of the material between the two substrates, pulling the substrate apart by hand, and visually assessing the area of cohesive failure. Three configurations can be used to make a sandwich. The average of the three individual sandwiches is reported rounded up to 5%. Standard entries can be defined. 100% cohesive failure indicates good adhesion of the material. Percentage cohesive failure can be evaluated and reported.

<Examples 1 to 11 and Comparative Example 1>

The following components were uniformly mixed according to the composition (parts by mass) shown in Tables 1 to 3 to prepare a one-component curable silicone composition of Examples 1 to 11 and Comparative Example 1. In the formula, Vi represents a vinyl group and Me represents a methyl group. Moreover, in Tables 1 to 3, “SiH/Vi” represents the total moles of silicon-bonded hydrogen atoms in component (B) per mole of total vinyl groups in component (A) in a one-component curable silicone composition.

The following components were used as component (A).

Component (a-1): 74 mass% of dimethylpolysiloxane capped with dimethylvinylsiloxy groups having a viscosity of 40,000 mPa·s at both molecular ends and a vinyl group content of 0.09 mass%, and a vinyl group content of 1.89 mass% A mixture of 26 mass% of an organopolysiloxane resin represented by the following average unit formula (A) and having a vinyl group content of 0.56 mass%:

(A) (Me ₂ ViSiO _1/2 ) _0.05 (Me ₃ SiO _1/2 ) _0.47 (SiO _4/2 ) _0.48

Component (a-2): Dimethylpolysiloxane capped with dimethylvinylsiloxy groups having a viscosity of 10,000 mPa·s at both molecular ends and a vinyl group content of 0.14% by mass.

Component (a-3): Dimethylpolysiloxane capped with dimethylvinylsiloxy groups having a viscosity of 2,000 mPa·s at both molecular ends and a vinyl group content of 0.23% by mass.

The following components were used as component (B).

Component (b-1): methylhydrogenpolysiloxane capped with trimethylsiloxy groups having a viscosity of 20 mPa·s at both molecular ends and a silicon-bonded hydrogen atom content of 1.56% by mass.

The following components were used as component (C).

Component (c-1): 1,3-divinyl-1,1,3,3-tetramethyl disiloxane solution of platinum 1,3-divinyl-1,1,3,3-tetramethyldisiloxane complex (Platinum metal content = approximately 8,800 ppm).

The following components were used as component (D).

Component (d-1): 1-ethynyl-cyclohexane-1-ol

Component (d-2): Bis (2-methoxy-1-methylethyl) maleate

The following components were used as component (E).

Component (e-1): 3-methacryloxypropyl trimethoxysilane

Component (e-2): methyl methacrylate

Component (e-3): hydroxypropyl acrylate

Component (e-4): 2-hydroxyethyl methacrylate

Ingredient (e-5): glycidyl methacrylate

Component (e-6): 3-glycidoxypropyl trimethoxysilane

The following ingredients were used as optional ingredients.

Component (f-1): Carbon black powder (This carbon black powder was added as a master batch consisting of 50 mass% of this carbon black powder and 50 mass% of the above component (a-3).)

[Table 1]

[Table 2]

[Table 3]

<Example 13>

The one-component curable silicone composition prepared in Example 8 was cured on the substrate shown in Table 4 by heating at 80° C. for 30 minutes, and the adhesive properties were evaluated as follows.

<Adhesive properties>

The pull-off adhesion test can be one of the other adhesion test methods. The test method is described as follows. The procedure of the pull-off adhesion test is as follows. First, the prepared Teflon zig was placed on a metal substrate; Second, the potting adhesive material was filled into a 6 mm diameter Teflon hole, and then the adhesive material was cured in an oven at 80° C. for 1 hour. Third, the Teflon jig was removed from the substrate, and then a pull-off test was performed by manual measurement. The degree of adhesion performance was determined whether or not cohesive failure on the substrate (glass, Al, EMC, PCB, PET) was fully observed.

[Table 4]

Industrial availability

The one-component curable silicone composition of the present invention has excellent storage stability, does not need to be mixed before use, cures at a relatively low temperature, and forms a cured product that exhibits excellent adhesion to various substrates contacted during curing. Consequently, it is ideal as an adhesive, coating or sealant for electrical/electronic devices.

Many variations and other embodiments of the invention will be apparent to those skilled in the art, assisted by the teachings presented in the foregoing description. Therefore, it should be understood that the present invention is not limited to the specific embodiments disclosed, but variations and other embodiments are intended to be included within the scope of the appended claims.

Claims (6)

As a one-component curable silicone composition,
(A) an organopolysiloxane having two or more silicon-bonded alkenyl groups per molecule;
(B) an organohydrogenpolysiloxane having two or more silicon-bonded hydrogen atoms per molecule, the content of silicon-bonded hydrogen atoms being at least 1% by mass of component (B), and silicon-bonding in component (B) The organohydrogenpolysiloxane in an amount such that the content of the hydrogen atom is 0.1 to 10 mol per mol of the silicon-bonded alkenyl group in component (A);
(C) a platinum group metal-based hydrosilylation catalyst, wherein the platinum group metal-based hydrosilylation catalyst in an amount of 1 to 200 ppm of the platinum group metal in component (C) in mass units for the composition;
(D) an inhibitor of a hydrosilylation reaction in an amount of 0.1 to 1% by mass of the composition; And
(E) Acrylic and/or methacrylic compounds in an amount of 0.1 to 5% by mass of the composition.
Containing, one-component curable silicone composition. The component (A) according to claim 1,
(A-1) is a straight chain organopolysiloxane having two or more silicon-bonded alkenyl groups per molecule;
(A-2) An organopolysiloxane resin composed of R ¹ ₃ SiO _1/2 units and SiO _4/2 units, wherein the molar ratio of (R ¹ ₃ SiO _1/2 units)/(SiO _4/2 units) is 0.6 to 1.7 And each R ¹ represents a monovalent hydrocarbon group having 1 to 12 carbon atoms, but two or more R ¹ per molecule is an alkenyl group having 2 to 12 carbon atoms, the organopolysiloxane resin; or
A one-component curable silicone composition, which is a mixture of component (A-1) and component (A-2). The component (A) is a mixture of component (A-1) and component (A-2), and the content of component (A-1) is the component (A-1) and component (A-2). ), a one-component curable silicone composition of 10% by mass or more. The one-component curable silicone composition according to any one of claims 1 to 3, wherein component (D) comprises acetylene alcohol and an unsaturated carboxylic ester. The one-component curable according to any one of claims 1 to 4, wherein component (E) is 3-methacryloxypropyl trimethoxysilane, 3-methacryloxypropyl triethoxysilane or methyl methacrylate. Silicone composition. The one-component curable silicone composition according to any one of claims 1 to 5, wherein the composition is an adhesive for an electrical/electronic device, a sealant or a coating agent.