KR20230074529A - UV curable organic modified silicone composition and cured product - Google Patents

Abstract

(A) a polymer represented by formula (1), [wherein X is each independently a divalent group represented by formula (2), Y is each independently represented by any one of formulas (3) to (5) A monovalent group, Y' is a divalent group independently represented by formula (6) or (7), and m is an integer of 0 to 12.] (B) In one molecule, a hydrogen atom bonded to a terminal silicon atom and (C) a platinum group metal catalyst activated by _light with _a wavelength of 200 to 500 nm and represented by HRSiO _2/2 (wherein R represents an organic group). The ultraviolet-curable, organically-modified silicone composition having no ganohydrogensiloxane unit undergoes rapid curing by a hydrosilylation reaction after irradiation with ultraviolet rays, and provides a cured product with high hardness without requiring post-curing.

Description

UV curable organic modified silicone composition and cured product

The present invention relates to an ultraviolet curable organically modified silicone composition and a cured product thereof, and more specifically, to materials for optical devices or optical parts, insulating materials for electronic devices or electronic parts, coating materials, adhesives, and nanoimprint applications. It relates to an ultraviolet-curable, organically-modified silicone composition useful as a mold material, etc., and a cured product thereof.

Organically modified silicones such as alkylene-modified silicone and arylene-modified silicone have characteristics such as high hardness, high toughness, and high gas barrier compared to dimethyl silicone. Because of these characteristics, organic modified silicone is used as a coating material for electronic members and a sealing material for light emitting diodes.

On the other hand, organic modified silicone needs to be cured by an addition crosslinking reaction, and in order to obtain a cured product having sufficient hardness, it must be cured by heating at a high temperature such as 150°C for several hours. Therefore, there was a difficulty in that it could not be applied to applications in which the size of the device was large and it was difficult to put it into a curing furnace, or applications requiring low-temperature curing properties due to heat resistance of the device.

On the other hand, UV-curable addition-curable silicone uses an ultraviolet-activated platinum catalyst, and since crosslinking proceeds with ultraviolet irradiation as a starting point, curing at a relatively low temperature is possible. In addition, since there is no inhibition of oxygen curing, there is no need for a step of replacing the inside of the system with an inert gas during curing or equipment therefor.

Until now, it has been known that a composition containing an addition polymer of vinylnorbornene and bis(dimethylsilyl)benzene and an organohydrogenpolysiloxane can be applied as an ultraviolet active type addition curing material (Patent Document 1).

However, even in this material, the curability after ultraviolet irradiation is insufficient, and post-curing is required to obtain a cured product.

Japanese Unexamined Patent Publication No. 2019-108471

The present invention has been made in view of the above circumstances, and curing by a hydrosilylation reaction proceeds rapidly after ultraviolet irradiation, providing an ultraviolet curable organically modified silicone composition that provides a cured product of high hardness without requiring post-curing. intended to provide

As a result of intensive studies to solve the above problems, the inventors of the present invention have found that the following composition is rapidly cured after irradiation with ultraviolet rays to provide a cured product with excellent hardness, and completed the present invention.

That is, the present invention,

1. (A) Polymer represented by structural formula (1):

[Wherein, X is each independently a divalent group represented by the following structural formula (2), Y is each independently a monovalent group represented by any one of the following structural formulas (3) to (5), and Y' is each It is a divalent group independently represented by the following structural formula (6) or (7), and Me represents a methyl group. m is an integer from 0 to 12;

(In the formula, an asterisk (*) represents a bonding site with a silicon atom.)

(In formulas (3) to (7), an asterisk (*) represents a bonding site with a silicon atom, and the steric configuration of each asymmetric carbon may be either cis (exo) or trans (endo). )]

(B) an organosilicon compound having at least three hydrogen atoms bonded to terminal silicon atoms in one molecule; and

(C) A platinum group metal catalyst activated by light with a wavelength of 200 to 500 nm

contains,

Further, an ultraviolet curable organically modified silicone composition having no organohydrogensiloxane unit represented by HRSiO _{2 / 2} (wherein R represents an organic group);

2. The compound (B) component represented by the following formula (I), the addition reaction product of phenyltrivinylsilane and 1,4-bis (dimethylsilyl) benzene represented by the following formula (II), or The ultraviolet curable organically modified silicone composition of 1 containing both of them;

(In formula (II), n is an integer of 1 to 20.)

3. 1 or 2 of the ultraviolet curable organically modified silicone composition in which the component (C) contains a (η ⁵ -cyclopentadienyl)trialiphatic platinum compound or a bis(β-diketonato)platinum compound;

4. Cured product of the ultraviolet curable organically modified silicone composition of any one of 1 to 3

provides

According to the present invention, since an organically modified silicone resin cured product having sufficient hardness can be obtained in a short time, technical or production problems of conventional materials can be solved. Moreover, since hardening can be advanced at room temperature, it is applicable also to the base material with low heat resistance.

Accordingly, the ultraviolet curable organically modified silicone composition of the present invention is useful as a material for an optical device or optical component, an insulating material for an electronic device or electronic component, a coating material, an adhesive, or a mold material for nanoimprint applications.

Hereinafter, the present invention will be specifically described.

[1] (A) component

Component (A) in the ultraviolet curable silicone resin composition of the present invention is a polymer represented by the following structural formula (1).

In formula (1), X is each independently a divalent group represented by the following structural formula (2), Y is each independently a monovalent group represented by any one of the following structural formulas (3) to (5), and Y ' is a divalent group each independently represented by the following structural formula (6) or (7), and Me represents a methyl group (hereinafter the same).

(In the formula, an asterisk (*) represents a bonding site with a silicon atom.)

(In formulas (3) to (7), an asterisk (*) represents a bonding site with a silicon atom, and the steric configuration of each asymmetric carbon may be either cis (exo) or trans (endo). )

In addition, the divalent group represented by the structural formula (6) or (7) is not limited to the bonding direction as described above, and includes structures in which individual structures are rotated by 180° on the paper surface.

Moreover, although m is an integer of 0-12, Preferably it is 1-5. When m exceeds 12, it becomes a high-viscosity liquid at room temperature and handling becomes difficult.

The kinematic viscosity of component (A) is not particularly limited, but is preferably 1,000 to 100,000 mm ² /s, and more preferably 5,000 to 30,000 mm ² /s. In the present invention, the kinematic viscosity is a value at 23° C. measured by a Canon-Fenske viscometer (the same applies hereinafter).

Component (A) is, for example, an addition reaction product of (a): bis(dimethylsilyl)benzene and (b):vinylnorbornene, which can be prepared according to a known method (Japanese Patent Laid-Open No. 2005-133073, etc.) can

Component (a) is ortho-, meta-, or para-substituted bis(dimethylsilyl)benzene represented by the following structural formula (8), and a single structure may be used, or a mixture of two or more types of isomers may be used.

Component (b) is 5-vinylbicyclo[2.2.1]hepta-2-ene represented by the following structural formula (9), and a single structure may be used, or a mixture of two or more types of isomers may be used.

Component (A) of the present invention is, for example, 1 mole of component (b) having two addition-reactive carbon-carbon double bonds per molecule relative to 1 mole of component (a) having two SiH groups per molecule. It can be obtained by subjecting an excess amount of more than 10 moles or less, preferably more than 1 mole to 5 moles or less, by addition reaction in the presence of a hydrosilylation reaction catalyst.

A known catalyst can be used as the hydrosilylation reaction catalyst. For example, platinum-based catalysts such as carbon powder carrying platinum metal, platinum black, platinic chloride, chloroplatinic acid, reaction products of chloroplatinic acid and monohydric alcohol, complexes of chloroplatinic acid and olefins, and platinum bisacetoacetate ; Platinum group metal type catalysts, such as a palladium type catalyst and a rhodium type catalyst, etc. are mentioned. In addition, the addition reaction conditions, use of solvent, etc. are not particularly limited, and may be carried out under known conditions.

As described above, when preparing component (A), component (b) is used in an excess molar amount relative to component (a), so component (A) has an addition reactivity derived from the structure of component (b) It has two carbon-carbon double bonds in one molecule.

In the case of using a component having addition reactive carbon-carbon double bonds as the component (B) described later, the addition reactive carbon-carbon double derived from component (A) occupies the entirety of the additional reactive carbon-carbon double bonds in the composition of the present invention. The bonding ratio is preferably 20 to 100 mol%, more preferably 40 to 100 mol%.

The said (A) component may be used individually by 1 type, and may be used in combination of 2 or more types.

[2] (B) component

Component (B) of the present invention is an organosilicon compound having at least three hydrogen atoms (hydrosilyl groups) bonded to terminal silicon atoms. Since such a terminal hydrosilyl group has high reactivity in the hydrosilylation reaction, formation of three-dimensional crosslinking proceeds rapidly, and a cured product having high hardness is provided.

In addition, component (B) is an organosilicon compound having no organohydrogensiloxane unit (D ^H unit) represented by HRSiO _{2 / 2} (wherein R represents an organic group), for example, the following formula ( The compound represented by I), the addition reaction product of phenyltrivinylsilane and 1,4-bis(dimethylsilyl)benzene represented by the following formula (II), the compound represented by the following formula (III), etc. there is.

(In formula (II), n is an integer of 1 to 20, preferably 1 to 10, and the broken line represents a bond.)

The kinematic viscosity of component (B) is not particularly limited, but is preferably 0.1 to 100,000 mm ² /s, more preferably 0.1 to 3,000 mm ² /s, still more preferably 0.5 to 500 mm ² /s.

The blending amount of component (B) is preferably 0.5 to 1.5 mol of hydrogen atoms bonded to silicon atoms per 1 mol of addition-reactive carbon-carbon double bonds of component (A) in the composition of the present invention, and is 0.8 to 1.5 mol. The amount used as 1.2 mol is more preferable.

The said (B) component may be used individually by 1 type, and may be used in combination of 2 or more types.

[3] (C) component

The platinum group metal catalyst for the hydrosilylation reaction of component (C) is inactive under light shading and is changed to an active platinum catalyst by irradiation with light having a wavelength of 200 to 500 nm, thereby reducing the addition reactive carbon-carbon double bonds in component (A) and (B) is a catalyst for accelerating a hydrosilylation reaction with silicon atom-bonded hydrogen atoms in component (B).

Specific examples of such component (C) include (η ⁵ -cyclopentadienyl) trialiphatic platinum compounds and derivatives thereof.

Particularly suitable among these are cyclopentadienyltrimethylplatinum complexes, methylcyclopentadienyltrimethylplatinum complexes, and derivatives thereof modified with a cyclopentadienyl group.

Further, bis(β-diketonato)platinum compounds are also exemplified as suitable examples of the component (C), and among these, bis(acetylacetonato)platinum compounds and their acetylacetonato group-modified derivatives are particularly suitable.

The compounding amount of component (C) is not limited as long as it is an amount that promotes curing (hydrosilylation reaction) of the composition, and the platinum group metal in the component is based on the total mass of component (A) and component (B) in the composition. It is preferably an amount in the range of 0.01 to 500 ppm in terms of atomic mass units, more preferably in the range of 0.05 to 100 ppm, still more preferably in the range of 0.01 to 50 ppm.

The said (C)component may be used individually by 1 type, and may be used in combination of 2 or more types.

[4] (D) component

In the composition of the present invention, when the composition is applied to a combination or substrate, a reaction control agent of component (D) may be added as necessary in order to prevent thickening or gelation before heating and curing.

Specific examples thereof include 3-methyl-1-butyn-3-ol, 3-methyl-1-pentyn-3-ol, 3,5-dimethyl-1-hexyn-3-ol, 1-ethynylcyclohexanol, Tinylmethyldecylcarbinol, 3-methyl-3-trimethylsiloxy-1-butyne, 3-methyl-3-trimethylsiloxy-1-pentyne, 3,5-dimethyl-3-trimethylsiloxy-1-hexyne, 1-ethynyl-1-trimethylsiloxycyclohexane, bis(2,2-dimethyl-3-butynoxy)dimethylsilane, 1,3,5,7-tetramethyl-1,3,5,7-tetra Vinyl cyclotetrasiloxane, 1,1,3,3-tetramethyl-1,3-divinyl disiloxane, etc. are mentioned.

Among these, 1-ethynylcyclohexanol, ethynylmethyldecylcarbinol, 3-methyl-1-butyn-3-ol, and bis(2,2-dimethyl-3-butynoxy)dimethylsilane are preferable.

The blending amount of component (D) is preferably 0.01 to 2.0 parts by mass, more preferably 0.01 to 0.1 parts by mass, based on 100 parts by mass in total of component (A) and component (B). If it is such a range, the effect of reaction control is fully exhibited.

Further, the ultraviolet curable organically modified silicone composition of the present invention is substantially free of organohydrogensiloxane units ( ^DH units) represented by HRSiO _{2 /2} (wherein R represents an organic group). Since such a side chain hydrosilyl group is inferior in reactivity to that of the terminal hydrosilyl group in the component (B), it may hinder the progress of the addition reaction.

[5] Other ingredients

The composition of the present invention may contain other components exemplified below, in addition to the above components (A) to (C) and component (D) used as needed, as long as the object of the present invention is not impaired.

For example, an adhesion imparting agent having a functional group group consisting of at least one alkenyl group, (meth)acrylic group, carbonyl group, epoxy group, alkoxysilyl group, and amide group in one molecule; thixotropic control agents such as fumed silica; reinforcing agents such as crystalline silica; antioxidants such as hindered phenols and hindered amines; light stabilizers; heat resistance improvers such as metal oxides and metal hydroxides; coloring agents such as titanium oxide; fillers imparting thermal conductivity, such as alumina and crystalline silica; Viscosity modifiers, such as non-reactive silicone oil which does not have a reactive functional group; conductivity imparting agents such as metal powder such as silver and gold; A pigment for coloring, a dye, etc. are mentioned.

The ultraviolet curable organically modified silicone composition of the present invention can be applied to various substrates and used as materials for optical devices or optical parts, insulating materials for electronic devices or electronic parts, coating materials, and mold materials for nanoimprint applications.

As the substrate, composite materials, metal members, plastic members, ceramic members, quartz glass, those used in the fields of coating, molding, bonding, and sealing of casings or members for electrical, electronic, and optical purposes can be used.

The composition of the present invention can also be used for a substrate activated by a known pretreatment step such as primer treatment, plasma treatment, excimer light treatment, or the like.

When curing the ultraviolet curable organically modified silicone composition of the present invention, a UV-LED lamp, a metal halide lamp, a mercury lamp, etc. may be used, and for light activation of the platinum catalyst, light having a wavelength of 200 to 500 nm, preferably 200 to 370 nm this is used

From the viewpoint of curing speed of the composition and preventing discoloration, the irradiation intensity is preferably 30 to 2,000 mW/cm ² , and the irradiation dose is preferably 3,000 to 100,000 mJ/cm ² . The temperature at the time of irradiation is preferably 10 to 60°C, and more preferably 20 to 40°C.

(Example)

Hereinafter, the present invention will be described in detail with examples and comparative examples, but the present invention is not limited to the following examples. In the following formula, Ph represents a phenyl group.

[Examples 1-3, Comparative Examples 1-4]

The following components (A) to (D) were mixed in the compounding amounts (parts by mass) shown in Table 1 to prepare an ultraviolet curable organically modified silicone composition.

(A) component

A mixture of polymers in which m in the above Structural Formula (1) is 1 to 5 (content ratio of addition reactive carbon-carbon double bonds: 0.47 mol/100 g)

(B) component

(B-1) A compound represented by the following structural formula (I) (kinematic viscosity at 23°C: 1.8 mm ² /s, content of hydrogen atoms bonded to silicon atoms: 0.0092 mol/g)

(B-2) is an addition product of phenyltrivinylsilane and 1,4-bis(dimethylsilyl)benzene, and is a mixture of compounds represented by the following structural formulas (a) to (d) [(a):(b): (c): (d) = 55:25:10:15 (molar ratio), kinematic viscosity at 23°C: 30,000 mm ² /s, average content of hydrogen atoms bonded to silicon atoms: 0.0035 mol/g]

(n = 4 to 10, the broken line represents the bonding hand.)

(B-3) Compound represented by the following structural formula (Kinematic viscosity at 23°C: 21.4 mm ² /s, content of hydrogen atoms bonded to silicon atoms: 0.0069 mol/g)

(In the formula, the arrangement of each parenthesized siloxane unit is random, alternating, or block)

(B-4) A compound represented by the following structural formula (kinematic viscosity at 23°C: 65 mm ² /s, content of hydrogen atoms bonded to silicon atoms: 0.0116 mol/g)

(In the formula, the arrangement of each parenthesized siloxane unit is random, alternating, or block)

(C) component

A toluene solution of a methylcyclopentadienyltrimethylplatinum complex having a platinum element content of 0.5% by mass

(D) component

Bis(2,2-dimethyl-3-butynoxy)dimethylsilane

[Cure State of Composition]

8 g of each obtained composition was irradiated with ultraviolet rays at room temperature (23° C.) at an irradiation intensity of 100 mW/cm ² and a dose of 30,000 mJ/cm ² using a UV-LED lamp with a wavelength of 365 nm, and the composition immediately after irradiation was The cured state was judged by finger contact.

Further, the hardness of the cured product at 23°C was evaluated with a JIS durometer type durometer. The results are listed together in Table 1.

As shown in Table 1, it is understood that the compositions prepared in Examples 1 to 3 are rapidly cured after irradiation with ultraviolet light at 23°C to provide a cured product with high hardness.

On the other hand, in the compositions prepared in Comparative Examples 1 to 4, it is understood that curing does not proceed immediately after ultraviolet irradiation.

Claims (4)

(A) a polymer represented by the following structural formula (1):

[Wherein, X is each independently a divalent group represented by the following structural formula (2), Y is each independently a monovalent group represented by any one of the following structural formulas (3) to (5), and Y' is each It is a divalent group independently represented by the following structural formula (6) or (7), and Me represents a methyl group. m is an integer from 0 to 12;

(In the formula, an asterisk (*) represents a bonding site with a silicon atom.)

(In formulas (3) to (7), an asterisk (*) represents a bonding site with a silicon atom, and the steric configuration of each asymmetric carbon may be either cis (exo) or trans (endo). )]
(B) an organosilicon compound having at least three hydrogen atoms bonded to terminal silicon atoms in one molecule; and
(C) A platinum group metal catalyst activated by light with a wavelength of 200 to 500 nm
contains,
Further, an ultraviolet curable organically modified silicone composition having no organohydrogensiloxane unit represented by HRSiO _{2 / 2} (wherein R represents an organic group). The compound according to claim 1, wherein the component (B) is a compound represented by the following formula (I) or the addition of phenyltrivinylsilane and 1,4-bis(dimethylsilyl)benzene represented by the following formula (II) An ultraviolet curable organically modified silicone composition comprising a reaction product or both.

(In Formula (II), n is an integer from 1 to 20.) The ultraviolet curable organically modified silicone composition according to claim 1 or 2, wherein the component (C) contains a (η ⁵ -cyclopentadienyl)trialiphatic platinum compound or a bis(β-diketonato)platinum compound. A cured product of the ultraviolet curable organically modified silicone composition according to any one of claims 1 to 3.