JP2021167282A - Succinic anhydride group-containing cyclic organosiloxane, addition-curable silicone composition comprising that succinic anhydride group-containing cyclic organosiloxane, and use of them - Google Patents

Abstract

To provide: a cyclic organosiloxane that can be used as an adhesive aid for an addition-curable silicone composition to form a cured product with good appearance and excellent adhesion to various substrates; and an addition-curable silicone composition comprising the same.SOLUTION: The present invention relates to: a succinic anhydride group-containing cyclic organosiloxane represented by general formula (1), where the succinic anhydride group-containing cyclic organosiloxane has, in a molecule, one succinic anhydride group, one or more hydrogen atoms directly bonded to silicon atoms, and one or more hydrolyzable silyl groups; an addition-curable silicone composition which comprises the succinic anhydride group-containing cyclic organosiloxane; and adhesive aids and adhesives based on them.SELECTED DRAWING: None

Description

The present invention relates to a succinic anhydride group-containing cyclic organosiloxane, an addition-curable silicone composition containing the succinic anhydride group-containing cyclic organosiloxane, and their use.

The addition-curable silicone adhesive composition is cured by heating at room temperature or, if necessary, to exhibit adhesiveness to various adherends. Additive silicone is used as an adhesive and a potting agent for in-vehicle electronic components and the like. Further, in order to improve the adhesiveness to the base material, an adhesive aid is used. Patent Document 1 proposes an organosilicon compound containing a hydrosilyl group (hydrogen atom directly bonded to a silicon atom) and having bisphenol A as a skeleton as an adhesive aid for a fluorine-containing adhesive. Further, Patent Document 2 proposes a cyclic organosiloxane having a hydrolyzable silyl group and two or more succinic anhydride groups as an adhesion aid for the organosiloxane composition.

Japanese Unexamined Patent Publication No. 2002-114793 Japanese Unexamined Patent Publication No. 2013-32498

There is an increasing demand for adhering metals such as aluminum and aluminum die casts and engineering plastics such as PPS, PBT and PET with an addition curable silicone adhesive composition. According to the findings of the present inventors, the adhesive aids described in Patent Documents 1 and 2 did not have a sufficient function as an adhesive auxiliary agent. That is, the silicone composition containing the adhesive aid described in Patent Documents 1 and 2 has a problem that the adhesiveness to various engineering plastics including PPS and metals is not sufficient.

An object of the present invention is to provide a cyclic organosiloxane that has excellent adhesiveness to various substrates and functions as an adhesive-imparting agent that gives a cured product having a good appearance. Another object of the present invention is to provide an addition-curable silicone composition containing the cyclic organosiloxane, which has excellent adhesiveness to various substrates and gives a cured product having a good appearance.

（式中、
Ｒ^１は、独立して、フッ素原子を含有しない１価の炭化水素基であり、
Ｒ^２は、独立して、炭素数２〜１０の２価の炭化水素基であり、
Ｒ^３は、独立して、Ｒ^２と同義であるか、下記一般式（２）で示される基：

であり、ここで、
Ｑ^１は、ｄで括られたシロキサン単位中のケイ素原子とエステル結合との間に２個以上の炭素原子を有する炭素鎖を形成する、直鎖状又は分岐状のアルキレン基を表し、
Ｑ^２は、酸素原子とＳｉＲ^４ _３−ｎ（ＯＲ^５）_ｎとの間に３個以上の炭素原子を有する炭素鎖を形成する、直鎖状又は分岐状のアルキレン基を表し、
Ｒ^４及びＲ^５は、それぞれ独立して、炭素原子数１〜４のアルキル基であり、
ｎは、１〜３の整数であり、
ａは、０又は１以上の整数であり、
ｂは、１以上の整数であり、
ｃは、１の整数であり、
ｄは、１以上の整数である）
［２］ａ＋ｂ＋ｃ＋ｄが３〜８の整数である、［１］の無水コハク酸基含有環状オルガノシロキサン。
［３］［１］又は［２］の無水コハク酸基含有環状オルガノシロキサンを用いた、接着助剤。
［４］（Ａ）ケイ素原子に結合したアルケニル基を、分子中に２個以上有するポリオルガノシロキサン；
（Ｃ）白金系触媒；及び
（Ｄ）［１］又は［２］の無水コハク酸基含有環状オルガノシロキサン；
を含み、任意として、（Ｂ）ケイ素原子に直接結合した水素原子を、分子中に３個以上有するポリオルガノハイドロジェンシロキサンを含む、付加硬化型シリコーン組成物。
［５］［４］の付加硬化型シリコーン組成物を用いた、接着剤。 The present invention relates to the following [1] to [5].
[1] A cyclic organosiloxane containing a succinic anhydride group represented by the following general formula (1).

(During the ceremony,
R ¹ is an independently monovalent hydrocarbon group that does not contain a fluorine atom.
R ² is independently a divalent hydrocarbon group having 2 to 10 carbon atoms.
R ³ is independently ^{synonymous with R 2} , or is a group represented by the following general formula (2):

And here,
Q ¹ is, to form a carbon chain having 2 or more carbon atoms between the silicon atom and an ester bond in enclosed siloxane units in d, represents a linear or branched alkylene group,
Q ² is, to form a carbon chain having 3 or more carbon atoms between the oxygen atom and _{^{SiR 4 3-n (OR 5}} ) n, represents a linear or branched alkylene group,
R ⁴ and R ⁵ are independently alkyl groups having 1 to 4 carbon atoms.
n is an integer from 1 to 3 and
a is an integer of 0 or 1 or more,
b is an integer greater than or equal to 1 and
c is an integer of 1
d is an integer greater than or equal to 1)
[2] The cyclic organosiloxane containing a succinic anhydride group according to [1], wherein a + b + c + d is an integer of 3 to 8.
[3] An adhesion aid using the succinic anhydride group-containing cyclic organosiloxane of [1] or [2].
[4] (A) A polyorganosiloxane having two or more alkenyl groups bonded to a silicon atom in the molecule;
(C) Platinum-based catalyst; and (D) Succinic anhydride group-containing cyclic organosiloxane of (D) [1] or [2];
(B) An addition-curable silicone composition comprising a polyorganohydrogensiloxane having three or more hydrogen atoms directly bonded to a silicon atom in the molecule.
[5] An adhesive using the addition-curable silicone composition of [4].

INDUSTRIAL APPLICABILITY The present invention provides a cyclic organosiloxane that has excellent adhesiveness to various substrates and functions as an adhesive-imparting agent that gives a cured product having a good appearance. Further, the present invention provides an addition-curable silicone composition containing the cyclic organosiloxane and having excellent adhesiveness to various substrates.

[Definition of terms]
The structural unit of the siloxane compound may be described by the following abbreviations (hereinafter, these structural units may be referred to as "M unit", " ^DH unit", etc.).
M : Si (CH ₃ ) ₃ O _1/2
^MH : SiH (CH ₃ ) ₂ O _1/2
M ^Vi : Si (CH = CH ₂ ) (CH ₃ ) ₂ O _1/2
D : Si (CH ₃ ) ₂ O _2/2
^DH : SiH (CH ₃ ) O _2/2
D ^Vi : Si (CH = CH ₂ ) (CH ₃ ) O _2/2
T : Si (CH ₃ ) O _3/2
Q : SiO _4/2 (tetrafunctional)

In the present specification, specific examples of the groups are as follows.
Examples of the monovalent hydrocarbon group include an alkyl group, a cycloalkyl group, an aryl group, an aralkyl group and an alkenyl group. Examples of the monovalent hydrocarbon group having no aliphatic unsaturated bond include the above-mentioned monovalent hydrocarbon group other than the alkenyl group.

The alkyl group is a linear or branched group having 1 to 18 carbon atoms, and is a methyl group, an ethyl group, a propyl group, a butyl group, a pentyl group, a hexyl group, an octyl group, a decyl group, a dodecyl group or a hexadecyl group. And octadecyl group and the like.
The cycloalkyl group is a monocyclic or polycyclic group having 3 to 20 carbon atoms, and examples thereof include a cyclopentyl group and a cyclohexyl group.
The aryl group is an aromatic group containing a monocyclic or polycyclic group having 6 to 20 carbon atoms, and examples thereof include a phenyl group and a naphthyl group.
The aralkyl group is an alkyl group substituted with an aryl group, and examples thereof include a 2-phenylethyl group and a 2-phenylpropyl group.
The alkenyl group is a linear or branched group having 2 to 6 carbon atoms, and examples thereof include a vinyl group, an allyl group, a 3-butenyl group and a 5-hexenyl group.
The monovalent hydrocarbon group may be unsubstituted or substituted with a substituent. Examples of the substituent include halogen atoms such as fluorine, chlorine and bromine; cyano groups and the like. Examples of the monovalent hydrocarbon group substituted with a halogen atom include a chloromethyl group, a chlorophenyl group, a 3,3,3-trifluoropropyl group and the like. Examples of the monovalent hydrocarbon group substituted with the cyano group include a 2-cyanoethyl group and the like.

Examples of the monovalent hydrocarbon group containing no fluorine atom include the above-mentioned monovalent hydrocarbon group which is unsubstituted or substituted with the above-mentioned substituent (excluding the fluorine atom).

The divalent hydrocarbon group is a group obtained by removing a hydrogen atom from the above-mentioned monovalent hydrocarbon group, and examples thereof include an alkylene group, a cycloalkylene group, an arylene group, an aralkylene group and an alkenylene group.
The alkylene group is a linear or branched group having 1 to 18 carbon atoms, and examples thereof include a methylene group, an ethylene group, a trimethylene group, a 2-methylethylene group and a tetramethylene group.
The divalent hydrocarbon group may be unsubstituted or substituted with the above-mentioned substituent, but preferably does not contain a fluorine atom.

（式中、Ｒ^１、Ｒ^２、Ｒ^３、Ｒ^４、Ｒ^５、ａ、ｂ、ｃ、ｄ及びｎは、前記したとおりである） [Succinic anhydride group-containing cyclic organosiloxane]
The succinic anhydride group-containing cyclic organosiloxane (hereinafter, also referred to as “cyclic organosiloxane”) is represented by the following general formula (1).

(In the formula, R ¹ , R ² , R ³ , R ⁴ , R ⁵ , a, b, c, d and n are as described above).

The succinic anhydride group-containing cyclic organosiloxane has an addition-curable silicone composition that gives a cured product having excellent adhesion to various substrates and a good appearance, particularly under curing conditions of 150 ° C. for 1 hour or 100 ° C. for 2 hours. Functions as an adhesive enhancer for objects. In addition, the succinic anhydride group-containing cyclic organosiloxane functions as an adhesive imparting agent that gives a cured product having a good appearance, particularly under curing conditions of 150 ° C. for 1 hour. That is, the cured product of the addition-curable silicone composition containing an adhesion aid composed of a cyclic organosiloxane containing a succinic anhydride group has a smooth surface and no liquid oozing on the surface. In addition, the succinic anhydride group-containing cyclic organosiloxane also functions as an adhesive imparting agent that gives a cured product having a good appearance even after heating. That is, it has an appearance in which yellowing is suppressed even when a cured product of an addition-curable silicone composition containing an adhesion aid composed of a cyclic organosiloxane containing a succinic anhydride group is further heated.

The succinic anhydride group-containing cyclic organosiloxane may be a random copolymer, a block copolymer, or a combination thereof. In the formula (1), a to d indicate the number in which each unit defined by a to d exists. In the formula (1), the units defined by a to d may be the same or different.

R ¹ is independently a monovalent hydrocarbon group containing no fluorine atom. R ¹ is preferably an alkyl group containing no fluorine atom, more preferably an unsubstituted alkyl group, further preferably an unsubstituted alkyl group having 1 to 4 carbon atoms, and a methyl group. Is particularly preferable.

R ² is independently a divalent hydrocarbon group having 2 to 10 carbon atoms. R ² is preferably an alkylene group, an ethylene group, a trimethylene group, particularly preferably a 2-methylethylene group.

Ｑ^１は、ｄで括られたシロキサン単位中のケイ素原子とエステル結合との間に２個以上の炭素原子を有する炭素鎖を形成する、直鎖状又は分岐状のアルキレン基を表し、Ｑ^２は、酸素原子とＳｉＲ^４ _３−ｎ（ＯＲ^５）_ｎとの間に３個以上の炭素原子を有する炭素鎖を形成する、直鎖状又は分岐状のアルキレン基を表す。 R ³ is ^{synonymous with R 2} or is a group represented by the following general formula (2).

Q ¹ represents a linear or branched alkylene group that forms a carbon chain having two or more carbon atoms between a silicon atom and an ester bond in a siloxane unit enclosed in d, and Q ² forms a carbon chain having 3 or more carbon atoms between the oxygen atom and _{^{SiR 4 3-n (oR 5}} ) n, represents a linear or branched alkylene group.

Q ¹ is, in view synthesis and handling are easy, ethylene group _(-CH 2 CH ₂ -) and 2-methylethylene group _{(-CH 2 CH (CH 3)} -) is preferred. Q ² is preferably _{a trimethylene group (-CH 2} CH ₂ CH _2- ) because it is easy to synthesize and handle.

R ⁴ and R ⁵ are independently alkyl groups having 1 to 4 carbon atoms. R ⁴ is preferably a methyl group and an ethyl group, and particularly preferably a methyl group, from the viewpoint of easy synthesis. R ⁵ is preferably a methyl group or an ethyl group, and particularly preferably a methyl group, from the viewpoint of giving good adhesiveness and easily volatilizing the alcohol generated by hydrolysis.

R ³ is ^{preferably synonymous with R 2,} and is particularly preferably an alkylene group. When R ³ is the preferred option, the polyorganosiloxane having an unsaturated group contained in the silicone composition is a hydrogen atom directly bonded to a silicon atom when used as an adhesion aid for the addition-curable silicone composition. Addition reaction to silicon becomes easy.

n is an integer of 1 to 3. n is preferably an integer of 2 to 3 from the viewpoint of providing good adhesiveness.

a is an integer of 0 or 1 or more. a is preferably an integer of 0 or 1-3, and particularly preferably an integer of 0 or 1-2, from the viewpoint of easy synthesis and handling.

b is an integer of 1 or more. When b is an integer of 1 or more, the succinic anhydride group-containing cyclic organosiloxane has a hydrosilyl group (hydrogen atom directly bonded to a silicon atom) involved in the addition reaction. b is 1 to 5 from the point that it acts as a bridge between the silicone composition and various members to be bonded as a component that imparts adhesiveness, and in some cases, the cyclic organosiloxane component alone serves as a cross-linking point of the silicone composition. It is preferable that it is an integer of 1, and it is particularly preferable that it is an integer of 1 to 3. When b is 0, there is no bridging effect and the adhesiveness is poor. That is, such a contained cyclic organosiloxane is inferior in function as an adhesive aid. On the other hand, in the silicone composition containing the cyclic organosiloxane containing a succinic anhydride group in which b is an integer of 5 or less, a cured product having excellent rubber elasticity can be obtained.

c is an integer of 1. When c is an integer of 1, the cyclic organosiloxane contains a succinic anhydride group. When c is an integer of 2 or more, the number of succinic anhydride groups becomes too large, so that the compatibility with the silicone composition deteriorates and the storage stability due to separation or the like deteriorates, and the content of such succinic anhydride groups The silicone composition containing the cyclic organosiloxane gives a cured product having poor adhesiveness to various substrates. That is, such a contained cyclic organosiloxane is inferior in function as an adhesive aid.

d is an integer of 1 or more. When d is an integer of 1 or more, the succinic anhydride group-containing cyclic organosiloxane has a hydrolyzable silyl group involved in the hydrolysis reaction. d is preferably an integer of 1 to 5, and particularly preferably an integer of 1 to 3, from the viewpoint of imparting adhesiveness to inorganic members such as metals and ceramics. As the silicone composition containing the cyclic organosiloxane containing a succinic anhydride group in which d is in the above range, a cured product having an appropriate hardness can be obtained. In addition, it has good compatibility with the silicone composition, is less likely to separate, and has excellent storage stability.

Further, a + b + c + d is an integer of 3 or more. When a + b + c + d is an integer of 3 or more, the main skeleton becomes a cyclic organosiloxane. a + b + c + d is preferably an integer of 3 to 8 and particularly preferably an integer of 3 to 6 from the viewpoint of easy synthesis. That is, when a + b + c + d is an integer of 3 or more, it is easy to synthesize the ring body of _{D a} D ^H _{8-a which can be a raw material.} When a + b + c + d is an integer of 8 or less, when isolating D ^aDH _{8-a which can be a} raw material, the target product (D) is selected from a mixture such as a cyclic product (7-membered ring or 9-membered ring) close to this. it becomes easy to separate and purify _a D ^H _8-a). Thereby, a cyclic organosiloxane having high purity can be obtained.

(Use of cyclic organosiloxane containing succinic anhydride group)
The succinic anhydride group-containing cyclic organosiloxane can be used as an adhesion aid for improving the adhesiveness of the addition-curable silicone composition. Such an addition-curable silicone composition will be described later.

(Method for producing cyclic organosiloxane containing succinic anhydride group)
The succinic anhydride group-containing cyclic organosiloxane can be prepared by using a method known to those skilled in the art or a similar method. Specific examples of the succinic anhydride group-containing cyclic organosiloxane include a cyclic siloxane having three or more hydrogen atoms directly bonded to a silicon atom and an unsaturated bond such as vinyltrimethoxysilane or 3-methacryloxypropyltrimethoxysilane. A method for obtaining a siloxane having a structure represented by the general formula (1) by reacting with an alkoxysilane having a siloxane and then reacting with a succinic anhydride having an unsaturated bond, or a hydrogen atom directly bonded to a silicon atom. Reacting a cyclic siloxane having three or more with an succinic anhydride having an unsaturated bond, and then reacting with an alkoxysilane having an unsaturated bond such as vinyltrimethoxysilane or 3-methacryloxypropyltrimethoxysilane. Then, a method of obtaining a siloxane having a structure represented by the general formula (1) can be mentioned. Those skilled in the art can appropriately select the reaction conditions, purification method, and the like. From the viewpoint that a high-purity product can be easily obtained, it is a 4-membered ring from the viewpoint that it is easy to synthesize and purify a cyclic body containing a hydrogen atom directly bonded to a silicon atom, which is a raw material, and is directly attached to a silicon atom. Anhydrous succinic acid using a cyclic siloxane having three bonded hydrogen atoms, where a is 1 and a + b + c + d is 4, or a using a cyclic siloxane having four is 0 and a + b + c + d is 4. A method for producing a group-containing cyclic organosiloxane is preferable.

[Additionally curable silicone composition]
The addition-curable silicone composition (hereinafter, also simply referred to as “silicone composition”) contains the above-mentioned succinic anhydride group-containing cyclic organosiloxane. Since the silicone composition contains a succinic anhydride group-containing cyclic organosiloxane, various substrates, especially metals (aluminum, aluminum die cast, etc.), and engineering plastics (polybutylene terephthalate resin (PBT resin), polyphenylene sulfide resin (PPS)). Excellent adhesiveness to (resin), polyethylene terephthalate resin (PET resin), etc.) can be achieved.

The silicone composition is not particularly limited as long as it is a silicone composition capable of forming a crosslinked structure by utilizing an addition reaction between an alkenyl group bonded to a silicon atom and a hydrogen atom directly bonded to a silicon atom. Specifically, the silicone composition contains the following components:
(A) Polyorganosiloxane having two or more alkenyl groups bonded to a silicon atom in the molecule;
(C) Platinum-based catalyst; and (D) Succinic anhydride group-containing cyclic organosiloxane;
(B) A polyorganohydrogensiloxane having three or more hydrogen atoms directly bonded to a silicon atom in the molecule (excluding the component (D)) is included.

In the present specification, "(A) a polyorganosiloxane having two or more alkenyl groups bonded to a silicon atom in a molecule" is also referred to as "(A) component". The same applies to "(C) platinum-based catalyst" and the like.

In a silicone composition containing a component (A), a component (C) and a component (D), and optionally a component (B), the number of hydrosilyl groups (that is, b) and the component (A) contained in the component (D). Depending on the number of alkenyl groups contained in the silicone composition, an addition-curable silicone composition can be obtained. Specifically, it is as follows.
(I) When the number of alkenyl groups contained in the component (A) is two or more, the silicone composition can further contain the component (B) to obtain an addition-curable silicone composition. In this case, the value of b in the component (D) can be 1 or more.
(Ii) When the number of alkenyl groups contained in the component (A) exceeds 2, the addition-curable silicone composition can be obtained by including the component (D) in which the value of b is 2 or more. .. In this case, the silicone composition may further contain the component (B) and may further contain the component (D) having a value of b of 1.
(Iii) When the number of alkenyl groups contained in the component (A) is 2, the addition-curable silicone composition can be obtained by including the component (D) in which the value of b is 3 or more. .. In this case, the silicone composition may further contain the component (B) and may further contain the component (D) having a value of b of 1 or 2.
Examples of such a silicone composition include the following first, second or third silicone compositions.

(First Silicone Composition)
The first silicone composition comprises a succinic anhydride group-containing cyclic organosiloxane in which b is an integer of 1. In this case, the first silicone composition has (A1) a polyorganosiloxane having two or more alkenyl groups bonded to a silicon atom in the molecule; (B) a hydrogen atom directly bonded to the silicon atom in the molecule. It contains a polyorganohydrogensiloxane having three or more; (C) a platinum-based catalyst; and (D1) a cyclic organosiloxane containing a succinic anhydride group in which b is an integer of 1.

In the first silicone composition, since the component (B) has three or more hydrogen atoms directly bonded to the silicon atom in the molecule, even if b in the component (D1) is an integer of 1, (A1). A cured product can be formed by the cross-linking reaction of the component and the component (B). The first silicone composition may contain (D) a succinic anhydride group-containing cyclic organosiloxane in which b is an integer of 2 or more.

(Second Silicone Composition)
The second silicone composition comprises a succinic anhydride group-containing cyclic organosiloxane in which b is an integer of 2. In this case, the second silicone composition contains (A2) a polyorganosiloxane having more than two alkenyl groups bonded to a silicon atom in the molecule; (C) a platinum-based catalyst; and (D2) b. Includes a succinic anhydride group-containing cyclic organosiloxane, which is an integer of 2.

In the second silicone composition, the number of alkenyl groups bonded to the silicon atom in the component (A2) exceeds two in the molecule. Therefore, even if b is an integer of 2, the cured product is subjected to the cross-linking reaction. Can be formed. The second silicone composition may further contain (D) a succinic anhydride group-containing cyclic organosiloxane in which b is an integer of 1 or 3 or more. Further, the second silicone composition may further contain (B) a polyorganohydrogensiloxane having three or more hydrogen atoms directly bonded to a silicon atom in the molecule.

(Third Silicone Composition)
The third silicone composition comprises a succinic anhydride group-containing cyclic organosiloxane in which b is an integer greater than or equal to 3. In this case, the third silicone composition has (A1) a polyorganosiloxane having two or more alkenyl groups bonded to a silicon atom in the molecule; (C) a platinum-based catalyst; and (D3) b having three or more. Includes an integer succinic anhydride group-containing cyclic organosiloxane.

In the third silicone composition, since the number of hydrogen atoms directly bonded to the silicon atoms in the component (D3) is 3 or more in the molecule, the cross-linking reaction of the components (A1) and (D3) causes the third silicone composition to undergo a cross-linking reaction. A cured product can be formed. The third silicone composition may contain (D) a succinic anhydride group-containing cyclic organosiloxane in which b is 1 or 2. Further, the third silicone composition may contain (B) a polyorganohydrogensiloxane having three or more hydrogen atoms directly bonded to a silicon atom in the molecule.

The components contained in the first, second or third silicone composition are as follows.

<(A1) Polyorganosiloxane having two or more alkenyl groups bonded to a silicon atom in the molecule>
(A1) A polyorganosiloxane having two or more alkenyl groups bonded to a silicon atom in the molecule (hereinafter, also referred to as “(A1) alkenyl group-containing polyorganosiloxane”) is a base polymer in a silicone composition. It is an ingredient. A network structure is formed in the cured product of the silicone composition by an addition reaction between the alkenyl group of the component (A1) and the hydrosilyl group (hydrogen atom directly bonded to the silicon atom) of the component (B) or the component (D). .. The component (A1) is not particularly limited as long as it can form the network structure together with the component (B) and / or the component (D). The component (A) is typically represented by the general formula (I) :.
(R ¹¹ ) _e (R ¹² ) _f SiO _{(4-ef) / 2} (I)
(During the ceremony,
R ¹¹ is an alkenyl group and
R ¹² is a monovalent hydrocarbon group having no aliphatic unsaturated bond.
e is an integer from 1 to 3 and
f is an integer from 0 to 2, where e + f is 1 to 3)
The molecule has two or more alkenyl group-containing siloxane units represented by. The number of alkenyl groups bonded to the silicon atom in (A1) is preferably 2 to 100, more preferably 2 to 50 in the molecule.

R ¹¹ is preferably a vinyl group from the viewpoint of easy synthesis and the fluidity of the silicone composition before curing. e is preferably 1 from the viewpoint of easy synthesis. R ¹² is preferably a methyl group or a phenyl group, preferably a methyl group, because it is easy to synthesize and has an excellent balance of properties such as mechanical strength and fluidity before curing. Especially preferable. Further, when the silicone composition before curing is applied to a base material, a polyorganosiloxane having only a methyl group and a polysiloxane having a phenyl group and a methyl group should be used in combination from the viewpoint of controlling the fluidity and thixo property. Can be done.

Examples of the organic group bonded to the silicon atom of the other siloxane unit in the component (A1) include a monovalent hydrocarbon group having no aliphatic unsaturated bond. The organic groups, from the same reason as the R ^12, preferably a methyl group or a phenyl group, and particularly preferably a methyl group.

R ¹¹ may be present at either the end or the middle of the molecular chain of the component (A1), or may be present at both of them.

The siloxane skeleton of the component (A1) can be linear or branched. That is, the component (A) can be (A1-1) linear polyorganosiloxane or (A1-2) branched polyorganosiloxane.

(A1-1) Examples of the linear polyorganosiloxane, both terminals blocked with _R 3 _{SiO 1/2} units, linear polyorganosiloxane intermediate unit is ^R ₁₂ 2 _{SiO 2/2} units (wherein R is R ¹¹ or R ¹² , R ¹¹ is an alkenyl group, R ¹² is a monovalent hydrocarbon group having no aliphatic unsaturated bond, and two or more Rs in the molecule. ¹¹ ). (A1-1) _R 3 _{SiO 1/2} units in ^component, R ¹¹ _R 12 _{2 SiO 1/2} ^units, that _R 11 is ² R 12 _{SiO 1/2} units or ^R ₁₁ 3 _{SiO 1/2} units It is preferable, and it is particularly preferable that it is ^{R 11} R ¹² ₂ SiO _{1/2 unit.}

(A1-2) The branched polyorganosiloxane includes SiO _4/2 units and R ₃ SiO _{1/2 units as essential units, and R 2} SiO _2/2 units and / or RSiO as arbitrary units. _Examples include branched polyorganosiloxanes containing 3/2 units. Here, R is R ¹¹ or R ¹² , and in R, two or more per molecule is R ¹¹ . As a crosslinking point in the curing reaction, in R, at least three of R per molecule is R ^11, is preferably the remainder is R ^12. From the viewpoint that the cured product of the silicone composition has excellent mechanical strength, _{the ratio of R 3} SiO _1/2 unit to SiO _4/2 unit is in the range of 1: 0.8 to 1: 3 as a molar ratio. A semi-solid resinous material that is solid or viscous at room temperature is preferable.

In the component (A1-2), R ¹¹ may exist as R of _{R 3} SiO _1/2 unit, or may exist as R of _{R 2} SiO unit or RSiO _{3/2 unit.}

The viscosity of the component (A1) is preferably 0.1 to 500 Pa · s, more preferably 0.3 to 300 Pa · s, and preferably 0.5 to 200 Pa · s at 23 ° C. Especially preferable. When the viscosity of the component (A1) is in the above range, the adhesiveness to various substrates can be efficiently enhanced, and the uncured silicone composition exhibits good fluidity and is cast. It exhibits excellent workability during potting and potting, and the cured product of the silicone composition exhibits excellent mechanical strength and moderate elasticity and hardness. Further, the viscosity of the component (A1) is preferably high from the viewpoint of further enhancing the adhesiveness even at room temperature. Here, when the component (A1) is a combination of two or more kinds, the viscosity of the component (A1) means the viscosity of the mixed alkenyl group-containing polyorganosiloxane. In the present specification, the viscosity is a value measured under the condition of 23 ° C. by appropriately setting the spindle number and the rotation speed using a rotational viscometer in accordance with JIS K 6249.

The component (A1) may be one kind or a combination of two or more kinds. For example, the component (A1) may be two or more (A1-1) linear alkenyl group-containing polyorganosiloxanes, or one or more (A1-1) linear alkenyl group-containing poly. It may be a mixture of an organosiloxane and one or more (A1-2) branched alkenyl group-containing polyorganosiloxanes.

As the component (A1), both ends are blocked with ^R 11 ^R ₁₂ 2 _{SiO 1/2} units, the intermediate unit is ^R ₁₂ 2 _{SiO 2/2} units, a viscosity at 23 ℃, 0.1~500Pa · Linear polyorganosiloxane s (in each of the above formulas, R is R ¹¹ or R ¹² , R ¹¹ is an alkenyl group, and R ¹² is a monovalent monovalent without an aliphatic unsaturated bond. a hydrocarbon group, and containing two or more ^{R 11)} in the molecule, and a _{SiO 4/2} units and _R 3 _{SiO 1/2} units as essential units, and _R 2 SiO as arbitrary units _A branched polyorganosiloxane containing 2/2 units and _3/2 units of RSiO (R is R ¹¹ or R ¹² , but at least 3 Rs per molecule in R are R 11 and the remainder is ^{R 11.} is preferably a combination of an R ¹² is). Further, the component (A1) ^{is particularly a linear polyorganosiloxane in which both ends are closed with M vi} units (dimethylvinylsiloxane units) and the intermediate unit is only D units (dimethylsiloxane units). preferable.

The component (A1) is not a component corresponding to the component (D). The component (A) preferably has no adhesion-imparting functional group other than the alkenyl group bonded to silicon. Further, it is particularly preferable that the component (A1) does not have one or more groups selected from an epoxy group, an alkoxy group bonded to silicon, and a hydrogen atom bonded to silicon.

<(A2) Polyorganosiloxane having more than two alkenyl groups bonded to silicon atoms in the molecule>
(A2) Polyorganosiloxane having more than two alkenyl groups bonded to silicon atoms in the molecule has more than two alkenyl groups bonded to silicon atoms in the molecule, except that it has more than two alkenyl groups in the molecule. The components (A1) including the preferred ones are as described above. The component (A2) is a mixture of a polyorganosiloxane having three or more alkenyl groups bonded to a silicon atom in the molecule and a polyorganosiloxane having two alkenyl groups bonded to a silicon atom in the molecule. May be good.

<(B) Polyorganohydrogensiloxane having 3 or more hydrogen atoms directly bonded to silicon atoms in the molecule>
(B) A polyorganohydrogensiloxane having three or more hydrogen atoms directly bonded to a silicon atom in the molecule (excluding the component (D)) (hereinafter, also referred to as "(B) polyorganohydrogensiloxane"). ) Is not particularly limited as long as it functions as a cross-linking agent for the component (A).

The component (B) is typically represented by the general formula (II) :.
(R ¹³ ) _g H _h SiO _{(4-g-h) / 2} (II)
(During the ceremony,
R ¹³ is a monovalent hydrocarbon group having no aliphatic unsaturated bond.
g is an integer from 0 to 2
h is an integer of 1-3, where g + h is an integer of 1-3)
It has 3 or more units in the molecule indicated by.

R ¹³ is preferably a methyl group from the viewpoint of easy synthesis. Further, h is preferably 1 from the viewpoint of easy synthesis.

The component (B) preferably has three or more siloxane units from the viewpoint of easy synthesis. Further, the number of siloxane units of the component (B) is preferably 6 to 200 because it does not volatilize even when heated to the curing temperature, has excellent fluidity, and is easily mixed with the component (A). , 10 to 150 are particularly preferable.

The siloxane skeleton in the component (B) may be linear, branched or cyclic, and is preferably linear.

Component (B), (B1) both ends, each ^{independently,} is closed by _R 14 _{3 SiO 1/2} units, an intermediate unit consists only of ^R ₁₄ 2 _{SiO 2/2} units, linear polyorgano Hydrogen siloxane and polyorganohydrogen siloxane ^{consisting of only (B2) R 14} ₃ SiO _1/2 unit and SiO _4/2 unit (In each of the above formulas, R ¹⁴ is independently a hydrogen atom or a hydrogen atom or is a monovalent hydrocarbon group having no aliphatic unsaturated bonds, provided, however, that R ^14, preferably at least three are hydrogen atoms). (B1) in the case of components and component ^(B2), examples of _R 14 _{3 SiO 1/2} ^units, include _HR 15 _{2 SiO 1/2} units and ^R ₁₅ 3 _{SiO 1/2} ^units, _R 14 2 SiO _{2 /} the ₂ ^units, HR 15 _{SiO 2/2} units and ^R ₁₅ 2 _{SiO 2/2} units (in the above ^{formulas, R 15} is a monovalent hydrocarbon group having no aliphatic unsaturated bond) Can be mentioned. In the case of the component (B1), the hydrogen atom bonded to the silicon atom may be present at the terminal or in the intermediate unit, but is preferably present in the intermediate unit.

As the component (B), (B1-1) a linear polymethylhydrogensiloxane in which both ends are closed with M units (trimethylsiloxane units) and the intermediate unit is ^{only DH} units (methylhydrogensiloxane units). , (B1-2) Both ends are closed with M units (trimethylsiloxane units), and the intermediate units ^{consist only of D units (dimethylsiloxane units) and DH} units (methylhydrogensiloxane units), and 1 mol of dimethylsiloxane units. On the other hand, linear polymethylhydrogensiloxane having a methylhydrogensiloxane unit of 0.1 to 3.0 mol, (B1-3) both ends are ^{closed with MH} units (dimethylhydrogensiloxane units). , linear polymethyl hydrogen siloxane intermediate unit consists only of D ^H units (methylhydrogensiloxane units), it is closed by (B1-4) both terminals M ^H units (dimethyl siloxane units), the intermediate unit Is composed of only D unit (dimethylsiloxane unit) and ^DH unit (methylhydrogensiloxane unit), and the methylhydrogensiloxane unit is 0.1 to 3.0 mol with respect to 1 mol of dimethylsiloxane unit. More preferably, polymethylhydrogensiloxane and polymethylhydrogensiloxane consisting of only (B2-1) ^MH units (dimethylhydrogensiloxane units) and Q units (SiO _{2/2 units).} Further, it is particularly preferable that the component (B) contains the component (B-1) and / or the component (B-2).
The component (B) may be one kind or a combination of two or more kinds.

It is preferable that the component (B) is not a component corresponding to the component (D) and does not have a succinic anhydride group. In addition, the component (B) does not have an ester bond and / or has one or more groups selected from an aliphatic unsaturated hydrocarbon group, an epoxy group and an alkoxy group bonded to a silicon atom. It is preferable that there is no such thing.

<(C) Platinum-based catalyst>
The platinum-based catalyst (C) is a catalyst for accelerating the addition reaction between the alkenyl group and the hydrosilyl group in the silicone composition.

As the component (C), platinum chloride acid, a reaction product of platinum chloride acid and alcohol (for example, a catalyst of Lamorrow (platinum-octanol complex, US Pat. No. 3220972)), platinum-olefin complex, platinum-vinyl. Examples thereof include platinum compounds such as siloxane complexes, platinum-ketone complexes, and platinum-phosphine complexes. Of these, the reaction product of chloroplatinic acid and alcohol and the platinum-vinylsiloxane complex are preferable from the viewpoint of good catalytic activity, and are appropriately selected according to the purpose of use.
The component (C) may be one kind or a combination of two or more kinds.

<(D) Succinic anhydride group-containing cyclic organosiloxane>
The cyclic organosiloxane (D) containing a succinic anhydride group includes the following (D1), (D2) and (D3) depending on the number of b.
(D1) b is an integer of 1, succinic anhydride group-containing cyclic organosiloxane (D2) b is an integer of 2, and succinic anhydride group-containing cyclic organosiloxane (D3) b is an integer of 3 or more. The succinic anhydride group-containing cyclic organosiloxane (D1) component, (D2) and (D3) components are as described above, including preferred embodiments, except that the number of b is different. The component (D) may be one kind or a combination of two or more kinds, respectively.

<(E) Further ingredients>
The silicone composition may contain (E) additional components other than the components (A) to (D) as long as the effects of the present invention are not impaired. Examples of such a component include (E1) an inorganic filler, (E2) a reaction inhibitor, and (E3) various additives. (E) The additional components may be one kind or a combination of two or more kinds, respectively.

<< (E1) Inorganic Filler >>
The inclusion of the (E1) inorganic filler in the silicone composition imparts high mechanical strength to the cured product of the silicone composition. (E1) Inorganic fillers include reinforcing fillers such as fumigant silica, calcined silica, silica aerogel, precipitated silica, and fumigant titanium oxide; as well as siliceous soil, ground silica, aluminum oxide, zinc oxide, titanium oxide, etc. Non-reinforcing fillers such as alminosilicic acid, calcium carbonate, calcium carbonate, magnesium carbonate, zinc carbonate, calcium silicate, talc, and ferric oxide are required for extrusion workability and cured products of silicone compositions. It is selected according to the physical properties to be used. As the (E1) inorganic filler, a reinforcing filler is preferable, silica such as fuming silica, calcined silica, silica airgel and precipitated silica is more preferable, and fuming silica is particularly preferable.

(E1) if the inorganic filler is fumed silica, BET specific surface area of the inorganic filler is preferably 50 to 500 m ² / g, more preferably 80~400m ² / g, 100~300m ² / It is particularly preferable that it is g.

(E1) The inorganic filler may be treated with a surface treatment agent. Examples of such a surface treatment agent include organoalkoxysilane, organohalosilane, siloxane oligomers, and organosilazane.

<< (E2) Reaction Inhibitor >>
(E2) The reaction inhibitor is a component that suppresses the curing reaction rate of the silicone composition and contributes to the workability of handling and the improvement of the balance between the development of adhesiveness and the curing rate. (E2) The reaction inhibitor has an aliphatic unsaturated hydrocarbon group such as triallyl isocyanurate, diallyl methyl isocyanurate, diallyl ethyl isocyanurate, tributenyl isocyanurate and diallylphenyl isocyanurate, and has a silicon atom. Isocyanurates having no alkoxy group bonded to; organic compounds having a polar group in the molecule such as diallyl maleate; acetylene alcohols such as 3,5-dimethyl-1-hexin-3-ol and derivatives thereof, etc. Organic compounds having an unsaturated bond of the above; and the like.

<< (E3) Various additives >>
Depending on the purpose, the silicone composition further comprises (E3-1) an adhesive-imparting agent, (E3-2) a polyorganohydrogensiloxane having two hydrogen atoms directly bonded to a silicon atom, an organic solvent, and an inorganic pigment. (E3) Various additives such as organic pigments, thixotropy-imparting agents, viscosity modifiers for improving extrusion workability, ultraviolet inhibitors, antifungal agents, heat resistance improvers, flame retardant agents, etc. Can be done. (E3) The various additives may be one kind or a combination of two or more kinds, respectively.

(E3-1) The adhesiveness-imparting agent is selected from an aliphatic unsaturated hydrocarbon group, an epoxy group, a polar group such as a carbonyl group or an isocyanul group, an alkoxy group bonded to a silicon atom, and a hydrogen atom directly bonded to a silicon atom. It has two or more adhesive-imparting functional groups. The component (E3-1) is a component that imparts adhesiveness to various substrates to the composition, and can be appropriately selected from known adhesiveness-imparting agents applicable to the silicone composition. However, the (E3-1) adhesive-imparting agent is not a component (A) to a component (D), a component (E2), or a component (E3-2) described later.

(E3-2) The polyorganohydrogensiloxane having two hydrogen atoms directly bonded to the silicon atom is as described above in the component (B) except that there are two hydrogen atoms directly bonded to the silicon atom. be. As the component (E3-2), a linear polymethylhydrogensiloxane in which both ends are ^{closed with MH} units (dimethylhydrogensiloxane units) and the intermediate unit is only D units (dimethylsiloxane units) is preferable. The component (E3-2) is not a component corresponding to the component (D), and preferably does not have a succinic anhydride group. Further, the component (E3-2) contains one or more groups having no ester bond and / or selected from an aliphatic unsaturated hydrocarbon group, an epoxy group and an alkoxy group bonded to a silicon atom. It is preferable not to have it.

[Content]
The content of each component in the silicone composition is preferably as follows.
The content of the component (B) and (D) component is not particularly limited as long as it is an amount such as silicone composition cures, to the number Vi _A of alkenyl groups of the component (A), (B) component silicon atoms and the number _{H B} of hydrogen atoms directly bonded to the component (D) ratio of the total number _{H D} of hydrogen atoms bonded directly to silicon atoms _{{(H B + H D)} / Vi a} is 0.1 or more An amount of less than 10 is preferable, an amount of 0.2 to 8.0 is more preferable, and an amount of 0.3 to 5.0 is particularly preferable. In the composition _{{(H B + H D)} / Vi A} is, if it is 0.1 or more, the mechanical strength of the cured product excellent, is less than 10, to improve the adhesion to various members of the composition .. In the case where the silicone composition is free of component _{(B), {(H B + H D} ) / Vi A} is the _(H D / Vi _A).

The content of component (D), in addition to being a range satisfying the above _{{(H B + H D)} / Vi A}, with respect to 100 parts by weight of component (A), 0.1 It is more preferably 20 parts by mass, further preferably 0.5 to 10 parts by mass, and particularly preferably 1 to 5 parts by mass. When the content of the component (D) is 0.1 parts by mass or more with respect to 100 parts by mass of the component (A), the adhesiveness to various members is further enhanced, and when it is 20 parts by mass or less, the adhesiveness is efficient. And heat resistance can be improved.

The content of the component (C) is a catalytic amount with respect to the total amount of the silicone composition. Specifically, the content of the component (C) is preferably 0.1 to 1,000 mass ppm in terms of platinum metal atoms with respect to 100 parts by mass of the total composition, and is 0.5 to 200 mass ppm. It is particularly preferably mass ppm. When the content of the component (C) is in the above range, the curability is sufficient.

The content of the inorganic filler (E1) is preferably 0.1 to 60 parts by mass, particularly preferably 1 to 45 parts by mass with respect to 100 parts by mass of the component (A). With such a content, extrusion workability is excellent, and the obtained cured product is excellent in mechanical strength. The content of the surface treatment agent can be appropriately determined according to the specific surface area of the (E1) inorganic filler and the degree of surface treatment.

The content of the reaction inhibitor (E2) is preferably 0.001 to 20 parts by mass, particularly preferably 0.01 to 10 parts by mass with respect to 100 parts by mass of the component (A). Within such a range, the effect of the reaction inhibitor can be efficiently exerted.
The content of the component (E1) and the component (E) other than the component (E2) is not particularly limited as long as the purpose of use of the silicone composition is not impaired.

(Manufacturing method of silicone composition)
The silicone composition contains essential components (A), (C), (D), and optional components (B) and / or (E) in a universal kneader, kneader, or the like. It can be produced by uniformly kneading by a mixing means.

(Preferable embodiment of composition)
For stable long-term storage, the component (B) and the component (D) should be appropriately distributed and stored in two or more containers so that the component (C) is in a separate container. , May be mixed and used immediately before use.

(Use of silicone composition)
Since the silicone composition is excellent in adhesiveness to various substrates, it can be used as an adhesive to various substrates.

<Adhesion method>
The silicone composition shall be adhered to and cured on the object to be adhered by injection, dropping, casting, casting, extrusion from a container, etc., or by integral molding by transfer molding or injection molding. Therefore, it can be adhered to the object to be adhered at the same time. The curing conditions (that is, heating temperature and heating time) can be appropriately adjusted according to the heat resistant temperature of the member to which the silicone composition is applied. The heating temperature is preferably 80 to 180 ° C., more preferably 80 to 150 ° C., and particularly preferably more than 100 ° C. and 150 ° C. or lower, from the viewpoint of heat resistance and operability of the member to be bonded. .. From the viewpoint of the simplicity of the curing step, the heating time is preferably 1 minute to 24 hours, more preferably 1 minute to 12 hours, and particularly preferably 1 minute to 8 hours.

The material of the object to be bonded is not particularly limited, and is a metal such as aluminum, magnesium, nickel, iron, copper or an alloy thereof (for example, aluminum die cast), ABS (acrylonitrile butadiene styrene resin), polycarbonate resin, PBT. Examples thereof include polymers such as (polybutylene terephthalate resin) and PPS (polyphenylene sulfide resin).

(Use)
The composition can be used for mounting or sealing parts for automobiles and electric and electronic devices, for adhering semiconductors or general-purpose plastics, and the like. Specifically, the composition can be used as a sealing material, a potting material, or the like for automobile parts.

Hereinafter, the present invention will be described in more detail with reference to Examples and Comparative Examples. In these examples, parts indicate parts by mass and viscosities indicate viscosities at 23 ° C. The present invention is not limited to these examples.

(Ingredients used)
The components used in Examples and Comparative Examples are as follows.

(A) Mixture of alkenyl group-containing polyorganosiloxane A-1 and A-2 (amount of alkenyl group bonded to silicon atom 0.25 mmol / g). A-1: A-2 = 75:25 (weight ratio).
A-1: Both ends are ^{sealed in Mv} units, the intermediate unit consists of only D units, and the viscosity at 23 ° C is 100 Pa · s. Linear polymethylvinylsiloxane A-2: M units, ^Dvi units. and consists only Q units, branched polymethylvinylsiloxane molar units ratio represented by _M 6 ^D vi _{Q 8} (weight average molecular weight 5,000,1 average per molecule of about 5 vinyl groups)
The weight average molecular weight is a styrene-equivalent value measured by GPC (gel permeation chromatography). The device used to measure the weight average molecular weight is RI (Differential Refractometer) Model 2414 (Mobile Phase Toluene) manufactured by Japan Waters Corp.

(B) Polyorganohydrogensiloxane B: A linear polymethylhydrogensiloxane having both ends sealed in M units, intermediate units ^{consisting of only D units and DH} units, and a viscosity at 23 ° C. of 20 mPa · s. (Amount of hydrogen atom directly bonded to silicon atom 8.8 mmol / g)

(C) Platinum-based catalyst C: Platinum-octanol complex (complex having a platinum content of 4.0% by weight obtained by heating chloroplatinic acid with octanol)

(D) Succinic anhydride group-containing cyclic organosiloxane The succinic anhydride group-containing cyclic siloxane shown below was used. The molecular weights of the component (D) and the component (D') were determined based on the structural formula of the raw material.

[Example 1 of Synthesis Example]
Cyclic siloxane compound of (D-1) In a 300 ml flask equipped with a nitrogen gas introduction tube and a condenser, 23.5 g of toluene and 3- (trimethoxysilyl) propyl = 2-methyl-3- (2,4,6) 81.6 g (0.143 mol) of 8-pentamethylcyclotetrasiloxane-2-yl) propanoate and 0.05 g of an alumina-supported platinum catalyst were charged, and the temperature was raised to 120 ° C. with stirring under a nitrogen stream. 20 g (0.143 mol) of allyl succinic anhydride (manufactured by Tokyo Kasei) was added dropwise over about 30 minutes. The reaction was carried out at 120 ° C. for 10 hours to obtain a reaction solution. The obtained reaction solution was cooled to room temperature (23 ° C.), activated carbon was added to adsorb the alumina-supported platinum catalyst, and then the activated carbon was removed by filtration. Next, the obtained reaction solution was heated and stripped under reduced pressure to remove toluene to obtain 98 g of the desired cyclic siloxane compound. The yield was 97%. ^{1 As a result} of analysis by 1 H-NMR, it was confirmed that it was the target compound as follows.

[Example 2 of Synthesis]
Cyclic siloxane compound of (D-2) 113.3 g of toluene and 377.5 g (1.57 mol) of 2,4,6,8-tetramethyl-cyclotetrasiloxane in a 1 L flask equipped with a nitrogen gas introduction tube and a condenser. And 3.2 g of an alumina-supported platinum catalyst were charged, and the temperature was raised to 120 ° C. while stirring under a nitrogen stream. 155.1 g (1.046 mol) of vinyltrimethoxysilane was added dropwise over about 2 hours. The reaction was carried out at 120 ° C. for 2 hours to obtain a reaction solution. The obtained reaction solution was cooled to room temperature (23 ° C.), and the alumina-supported platinum catalyst was removed by filtration. The resulting reaction solution was heated and stripped under reduced pressure to remove toluene and unreacted components to give 352.5 g of reaction product. Next, the reaction product was distilled under reduced pressure to obtain a compound in which vinyltrimethoxysilane was added to 191.4 g of cyclic siloxane.

Next, in a 300 ml flask equipped with a nitrogen gas introduction tube and a condenser, 33.2 g (0.237 mol) of allylsuccinic anhydride (manufactured by Tokyo Kasei) and 92.1 g of a compound obtained by adding vinyltrimethoxysilane to the above cyclic siloxane. (0.237 mol) and 0.05 g of an alumina-supported platinum catalyst were charged, and the temperature was raised to 120 ° C. with stirring under a nitrogen stream. The reaction was carried out at 120 ° C. for 13 hours to obtain a reaction solution. The obtained reaction solution was cooled to room temperature (23 ° C.), activated carbon was added to adsorb the alumina-supported platinum catalyst, and then the activated carbon was removed by filtration to obtain 102.6 g of the target cyclic siloxane compound. .. The yield was 82%. ^{1 As a result} of analysis by 1 H-NMR, it was confirmed that it was the target compound as follows.

[Example 3 of Synthesis]
Cyclic siloxane compound of (D-3) In a 2 L flask equipped with a nitrogen gas introduction tube and a condenser, 133 g of toluene and 515.2 g (2.024 mol) of 2,2,4,6,8-pentamethyl-cyclotetrasiloxane were added. 4 g of an alumina-supported platinum catalyst was charged, and the temperature was raised to 120 ° C. while stirring under a nitrogen stream. 150 g (1.012 mol) of vinyltrimethoxysilane was added dropwise over about 2 hours. The reaction was carried out at 120 ° C. for 2 hours to obtain a reaction solution. The obtained reaction solution was cooled to room temperature (23 ° C.), and the alumina-supported platinum catalytic activity was removed by filtration. The resulting reaction solution was heated and stripped under reduced pressure to remove toluene and unreacted components to give 434.5 g of the reaction product. Next, the reaction product was distilled under reduced pressure to obtain a compound in which vinyltrimethoxysilane was added to 128.4 g of cyclic siloxane.

Next, in a 300 ml flask equipped with a nitrogen gas introduction tube and a condenser, 32.5 g (0.232 mol) of allylsuccinic anhydride (manufactured by Tokyo Kasei) and 93.4 g of a compound obtained by adding vinyltrimethoxysilane to the above cyclic siloxane. (0.232 mol) and 0.05 g of an alumina-supported platinum catalyst were charged, and the temperature was raised to 120 ° C. with stirring under a nitrogen stream. The reaction was carried out at 120 ° C. for 13 hours to obtain a reaction solution. The obtained reaction solution was cooled to room temperature (23 ° C.), activated carbon was added to adsorb the alumina-supported platinum catalyst, and then the activated carbon was removed by filtration to obtain 103.5 g of the target cyclic siloxane compound. .. The yield was 82%. ^{1 As a result} of analysis by 1 H-NMR, it was confirmed that it was the target compound as follows.

[Example 4 of Synthesis]
Cyclic siloxane compound of (D-4) 63.3 g of toluene and 288.3 g (1.2 mol) of 2,4,6,8-tetramethyl-cyclotetrasiloxane in a 500 mL flask equipped with a nitrogen gas introduction tube and a condenser. And 3 g of an alumina-supported platinum catalyst were charged, and the temperature was raised to 120 ° C. while stirring under a nitrogen stream. 28 g (0.2 mol) of allyl succinic anhydride (manufactured by Tokyo Kasei) was added dropwise over about 1 hour. The reaction was carried out at 120 ° C. for 16 hours to obtain a reaction solution. The obtained reaction solution was cooled to room temperature (23 ° C.), activated carbon was added to adsorb the alumina-supported platinum catalyst, and then the activated carbon was removed by filtration. The obtained reaction solution was heated and stripped under reduced pressure to remove toluene and unreacted components to obtain a compound in which 76.2 g of cyclic siloxane was added with allyl succinic anhydride.

Next, in a 300 ml flask equipped with a nitrogen gas introduction tube and a condenser, 60 g of toluene, 76.2 g (0.2 mol) of the compound in which allylsuccinic anhydride was added to the above cyclic siloxane, and 1.2 g of an alumina-supported platinum catalyst were placed. The temperature was raised to 120 ° C. with stirring under a nitrogen stream. 59.3 g (0.4 mol) of vinyltrimethoxysilane was added dropwise over about 2 hours. The reaction was carried out at 120 ° C. for 5 hours to obtain a reaction solution. The obtained reaction solution was cooled to room temperature (23 ° C.), activated carbon was added to adsorb the alumina-supported platinum catalyst, and then the activated carbon was removed by filtration. Next, the obtained reaction solution was heated and stripped under reduced pressure to remove toluene to obtain 132.4 g of the desired cyclic siloxane compound. The yield was 98%. ^{1 As a result} of analysis by 1 H-NMR, it was confirmed that it was the target compound as follows.

(D') Compounds for comparison The compounds shown below were used. Here, (D'-5) used [3- (trimethoxysilyl) propyl] succinic anhydride manufactured by Tokyo Kasei.

[Comparative Synthesis Example 1]
Synthesis of (D'-1) In a 5 L flask equipped with a nitrogen gas introduction tube and a condenser, 440 g of toluene and 2,2,4,6,6,8-hexamethyl-cyclotetrasiloxane 1991.9 g (7.42 mol). , 17.7 g of an alumina-supported platinum catalyst was charged, and the temperature was raised to 120 ° C. while stirring under a nitrogen stream. 1100 g (7.42 mol) of vinyltrimethoxysilane was added dropwise over about 1 hour. The reaction was carried out at 120 ° C. for about 3 hours. The obtained reaction solution was cooled to room temperature (23 ° C.), and the alumina-supported platinum catalyst was removed by filtration. The obtained reaction solution was heated and stripped under reduced pressure to remove toluene and unreacted components. Next, the reaction product was distilled under reduced pressure to obtain 400 g of the desired cyclic siloxane compound. The yield was 13%. ^{1 As a result} of analysis by 1 H-NMR, it was confirmed that it was the target compound as follows.

[Comparative synthesis example 2]
Synthesis of (D'-2) In a 500 ml flask equipped with a nitrogen gas introduction tube and a condenser, 42 g of toluene, 190.7 g (0.749 mol) of 2,2,4,6,8-pentamethyl-cyclotetrasiloxane and alumina. 0.1 g of a supported platinum catalyst was charged, and the temperature was raised to 120 ° C. with stirring under a nitrogen stream. 17.5 g (0.125 mol) of allyl succinic anhydride (manufactured by Tokyo Kasei) was added dropwise over about 1 hour. Next, the reaction was carried out at 120 ° C. for 12 hours to obtain a reaction solution. The obtained reaction solution was cooled to room temperature (23 ° C.), activated carbon was added to adsorb the alumina-supported platinum catalyst, and then the activated carbon was removed by filtration. Next, the obtained reaction solution was heated and stripped under reduced pressure to remove toluene and unreacted components to obtain 50 g of a reaction product.

Next, 50 g of toluene, 68.3 g (0.461 mol) of vinyltrimethoxysilane, and 1.5 g of an alumina-supported platinum catalyst were placed in a 500 ml flask equipped with a nitrogen gas introduction tube and a condenser, and the mixture was stirred under a nitrogen stream. However, the temperature was raised to 120 ° C. 49.5 g (0.125 mol) of the above reaction product was added dropwise over about 2 hours. Next, the reaction was carried out at 120 ° C. for 10 hours to obtain a reaction solution. The obtained reaction solution was cooled to room temperature (23 ° C.), activated carbon was added to adsorb the alumina-supported platinum catalyst, and then the activated carbon was removed by filtration. The obtained reaction solution was heated and stripped under reduced pressure to remove toluene and unreacted components to obtain 84.8 g of the desired cyclic siloxane compound. The yield was 98%. ^{1 As a result} of analysis by 1 H-NMR, it was confirmed that it was the target compound as follows.

[Comparative Synthesis Example 3]
Synthesis of (D'-3) In a 300 ml flask equipped with a nitrogen gas introduction tube and a condenser, 39 g (0.162 mol) of 2,4,6,8-tetramethyl-cyclotetrasiloxane, 40 g of toluene and an alumina-supported platinum catalyst 1 g was charged and the temperature was raised to 120 ° C. while stirring under a nitrogen stream. 45.45 g (0.324 mol) of allyl succinic anhydride (manufactured by Tokyo Kasei) was added dropwise over about 1 hour. The reaction was carried out at 120 ° C. for about 5 hours. Further, 96.2 g (0.649 mol) of vinyltrimethoxysilane was added dropwise over about 3 hours. The reaction was carried out at 120 ° C. for 16 hours to obtain a reaction solution. The obtained reaction solution was cooled to room temperature (23 ° C.), activated carbon was added to adsorb the alumina-supported platinum catalyst, and then the activated carbon was removed by filtration. The obtained reaction solution was heated and stripped under reduced pressure to remove toluene and unreacted components to obtain 127.6 g of the desired cyclic siloxane compound. The yield was 96%. ^{1 As a result} of analysis by 1 H-NMR, it was confirmed that it was the target compound as follows.

[Comparative Synthesis Example 4]
Synthesis of (D'-4) In a 200 ml flask equipped with a nitrogen gas introduction tube and a condenser, 38.8 g (0.161 mol) of 2,4,6,8-tetramethyl-cyclotetrasiloxane and alumina-supported platinum catalyst 0 8.8 g was charged and the temperature was raised to 120 ° C. while stirring under a nitrogen stream. 23.9 g (0.161 mol) of vinyltrimethoxysilane was added dropwise over about 1 hour. Further, 45.2 g (0.322 mol) of allyl succinic anhydride (manufactured by Tokyo Kasei) was added dropwise over about 2 hours. The reaction was carried out at 120 ° C. for 24 hours to obtain a reaction solution. The obtained reaction solution was cooled to room temperature (23 ° C.), activated carbon was added to adsorb the alumina-supported platinum catalyst, and then the activated carbon was removed by filtration to obtain 64.3 g of the desired cyclic siloxane compound. rice field. The yield was 60%. ^{1 As a result} of analysis by 1 H-NMR, it was confirmed that it was the target compound as follows.

[Comparative Synthesis Example 5]
Synthesis of (D'-6) In a 200 ml flask equipped with a nitrogen gas introduction tube and a condenser, 41 g (0.17 mol) of 2,4,6,8-tetramethyl-cyclotetrasiloxane and 1,3-divinyl of platinum were added. -1,1,3,3-tetramethyldisiloxane complex was added so that the platinum metal content was 2.5 ppm, and the reaction was carried out with 10 g (0.032 mol) of bisphenol A bisallyl ether. The unreacted 2,4,6,8-tetramethylcyclotetrasiloxane was removed by stripping to give 21 g of the cyclic siloxane compound of interest. ^{1 As a result} of analysis by 1 H-NMR, it was confirmed that it was the target compound as follows.

(E1) Inorganic filler E1-1: Quartz powder (Crystalite VX-S, manufactured by Ryumori Co., Ltd.)

(E2) Reaction inhibitor E2-1: Triallyl isocyanurate E2-2: 3,5-dimethyl-1-hexyne-3-ol

Example 1
(1) Preparation of base polymer (1) With the composition shown in Table 1, (A) alkenyl group-containing polyorganosiloxane and (E1) inorganic filler (E1-1) were put into a universal kneader and depressurized at 150 ° C. It was stirred down for 3 hours. After cooling to room temperature (23 ° C.), (E2) reaction inhibitors (E2-1 and E2-2) and (C) platinum-based catalyst are added, and the mixture is stirred for 15 minutes to prepare the base polymer (1). bottom.
(2) Preparation of Additive-Curing Silicone Composition With the compositions shown in Tables 2 to 4, (B) polyorganohydrogensiloxane and / or (D) succinic anhydride group-containing cyclic organosiloxane are added to the base polymer (1). Alternatively, a compound for comparison (D') was added and stirred to prepare an addition-curable silicone composition.

（Ｃ）は、ベースポリマー中の白金量を１２ｐｐｍとなる量である。

(C) is an amount that makes the amount of platinum in the base polymer 12 ppm.

(Evaluation method)
<Hardness>
The addition-curable silicone composition is poured into a 6 mm-thick Teflon (registered trademark) coated mold, covered with a Teflon (registered trademark) coated metal lid, and placed in a hot air circulation dryer at 150 ° C. for 1 hour. After curing and cooling to room temperature (23 ° C.), measurement was performed in accordance with JIS K6249.

<Presence / absence of discoloration (yellow)>
The cured product used in the above "hardness" measurement is further heated at 150 ° C. for 72 hours in a hot air circulation type dryer, and the appearance (degree of yellowing) is observed. The presence and degree of discoloration (yellow) was evaluated.
◎: No change from the initial stage 〇: Slight yellowing was observed compared to the initial stage ×: Yellowing was clearly observed

<Surface condition>
The addition-curable silicone composition is poured into a 2 mm-thick Teflon (registered trademark) coated mold, cured at 150 ° C. for 1 hour in a hot air circulation dryer, cooled to room temperature (23 ° C.), and after 24 hours. , The surface condition was observed.
Good: The surface was smooth and there was no liquid oozing on the surface when palpated. Bleed: Liquid oozing was seen on the surface of the cured product.

<Shear adhesion strength>
For details of the test, JIS K 6249 was followed. After applying the silicone composition to one end of the test piece and spreading it uniformly, the other end of the test piece has an adhesive thickness of 1 mm, a width direction of 25 mm, and a length direction (overlap margin) of 10 mm. The parts were pasted together to obtain a test piece. Place the test piece in an oven that has been fixed with a jig and adjusted to the temperature of the curing conditions, and in a hot air circulation dryer under the conditions of "150 ° C for 1 hour" or "100 ° C for 2 hours". It was cured and cooled to room temperature (23 ° C.) to obtain a test piece. The test piece was measured with a tensile tester at a tensile speed of 10 mm / min and used as "tensile shear adhesive strength" (MPa).

<Coagulation fracture rate>
The cohesive fracture rate is the rate at which the silicone layer is fractured without peeling at the interface of the adherends facing each other in the shear adhesion strength test. The fact that the cohesive fracture rate is 100% indicates that the adhesive strength (adhesiveness) is sufficiently maintained. After measuring the shear adhesion strength according to the above description of "shear adhesion strength", the value obtained by dividing the area of the silicone layer adhered to various adherends by the coating area was defined as the cohesive fracture rate (area%).

<Adhesion test>
A silicone composition was applied to a predetermined member so as to have a thickness of 2 mm, and cured at 100 ° C. under curing conditions for 2 hours. A knife was made at the interface between the member and the cured silicone composition, and the member was pulled in the 180 degree direction. The adhesive state was confirmed, and the adhesiveness was evaluated according to the following criteria.
⊚: Aggregate fracture Δ: Aggregate fracture and interfacial delamination mixed ×: Interfacial delamination

The results are summarized in Table 2, Table 3 and Table 4. Incidentally, _{"(H B + H D) /} Vi A " in Table varies depending on the presence or absence of the component (B), (D) component and the component (D '). That is, in Example 1, _{"(H B + H D) /} Vi A " is _"H D / Vi _A". In such embodiment 2, _{"(H B + H D) /} Vi A " becomes _{"(H B + H D) /} Vi A ". In Comparative Example 1, _{"(H B + H D) /} Vi A " is _"H B / Vi _A". In Comparative Example 2, and the like, _{"(H B + H D) /} Vi A " becomes _{"(H B + H D ')} / Vi A ". Further, the value of "D unit (a)" in the component (D) and the component (D') means the number of D units per structural formula. The same applies to other groups.

The abbreviations in the table are as follows.
Aluminum: A1050P (JIS H 4000): Pure aluminum with an aluminum purity of 99.5% or more Diecast: ADC-12 (JIS H 5302: 2006): Al—Si—Cu alloy PBT: Polybutylene terephthalate resin ( Made of Polyplastics, Juranex 2002)
PPS: Polyphenylene sulfide resin (manufactured by Tosoh, Sustil GS-40%)

As is clear from Tables 2-4, the silicone compositions of Examples showed excellent adhesion to various substrates under curing conditions of 150 ° C. for 1 hour or 100 ° C. for 2 hours. Further, the silicone composition of the example gives a cured product having a good appearance under the curing conditions of 150 ° C. for 1 hour, and yellowing after further heating the cured product at 150 ° C. for 72 hours is suppressed. rice field. Further, the adhesive aid of the example was able to improve the adhesiveness to various substrates by curing the silicone composition under the curing conditions of 150 ° C. for 1 hour or 100 ° C. for 2 hours. In particular, the silicone composition containing the adhesion aid of the examples was particularly excellent in the cohesive failure rate with respect to PPS, aluminum and aluminum die casting under the curing conditions of 100 ° C. for 2 hours. Therefore, it can be seen that the succinic anhydride group-containing cyclic organosiloxane represented by the general formula (1) is excellent as an adhesion aid.

Comparing Examples 2 and 3 with Examples 4 and 5, when R ^{3 was R 2} which is an alkylene group, the adhesiveness to various substrates was better.
According to the comparison of Examples 2 to 7, when the content of the component (D) is small, the cured product cured under the condition of 150 ° C. for 1 hour is more yellowed after being further heated at 150 ° C. for 72 hours. It was suppressed and the appearance of the cured product after heating was also good.
Comparing Examples 1 to 6 with Example 7, when d was 1, the adhesive strength to PBT and PPS was more excellent, especially under the curing conditions of 100 ° C. for 2 hours.

On the other hand, since the compositions of Comparative Examples 1 to 7 do not contain the component (D), the compositions of Comparative Examples 1 to 7 have poor adhesiveness to various substrates or have a good appearance. I couldn't get it. In particular, the compositions of Comparative Examples 1 to 7 were inferior in the cohesive failure rate with respect to PPS, aluminum and aluminum die casting under the curing conditions of 100 ° C. for 2 hours.
The composition of Comparative Example 1 contains only the component (B) which is a cross-linking agent as a component having a hydrogen atom directly bonded to a silicon atom. Therefore, the composition of Comparative Example 1 was inferior in adhesiveness.
The composition of Comparative Example 2 contains a cyclic organosiloxane containing a hydrosilyl group and no succinic anhydride group as an adhesion aid. Therefore, the composition of Comparative Example 2 was inferior in adhesiveness.
The composition of Comparative Example 3 contains a succinic anhydride group-containing cyclic organosiloxane having no hydrosilyl group as an adhesion aid. Therefore, bleeding was confirmed in the cured product of the composition containing the adhesive aid of Comparative Example 3 under the curing conditions of 150 ° C. for 1 hour. Further, the cured product of the composition containing the adhesion aid of Comparative Example 3 was particularly inferior in shear adhesion strength under the curing conditions of 100 ° C. for 2 hours.
The composition of Comparative Example 4 contains a succinic anhydride group-containing cyclic organosiloxane having two succinic anhydride groups as an adhesion aid. Therefore, bleeding was confirmed in the cured product of the composition containing the adhesive aid of Comparative Example 4 under the curing conditions of 150 ° C. for 1 hour. The cured product of the composition containing the adhesion aid of Comparative Example 4 was particularly inferior in shear adhesive strength under the curing conditions of 100 ° C. for 2 hours.
The composition of Comparative Example 6 contains a succinic anhydride group-containing silane compound as an adhesion aid, which does not have a hydrosilyl group and does not have a cyclic siloxane structure. Therefore, bleeding was confirmed in the cured product of the composition containing the adhesive aid of Comparative Example 6. Further, the cured product of the composition containing the adhesive aid of Comparative Example 6 was inferior in adhesiveness to various substrates.
The composition of Comparative Example 7 contains an organosilicon compound containing a hydrosilyl group and having bisphenol A as a skeleton as an adhesion aid. Therefore, the cured product of the composition containing the adhesion aid of Comparative Example 7 was inferior in shear adhesion strength to various substrates (particularly aluminum).
Further, in the compositions of Comparative Examples 4 to 7, yellowing was remarkable after the cured product cured under the condition of 150 ° C. for 1 hour was further heated at 150 ° C. for 72 hours, and the cured product after heating was remarkable. The appearance was inferior.

Claims (5)

A cyclic organosiloxane containing a succinic anhydride group represented by the following general formula (1).

(During the ceremony,
R ¹ is an independently monovalent hydrocarbon group that does not contain a fluorine atom.
R ² is independently a divalent hydrocarbon group having 2 to 10 carbon atoms.
Is R ³ independently synonymous with ^{R 2?}

And here,
Q ¹ is, to form a carbon chain having 2 or more carbon atoms between the silicon atom and an ester bond in enclosed siloxane units in d, represents a linear or branched alkylene group,
Q ² is, to form a carbon chain having 3 or more carbon atoms between the oxygen atom and _{^{SiR 4 3-n (OR 5}} ) n, represents a linear or branched alkylene group,
R ⁴ and R ⁵ are independently alkyl groups having 1 to 4 carbon atoms.
n is an integer from 1 to 3 and
a is an integer of 0 or 1 or more,
b is an integer greater than or equal to 1 and
c is an integer of 1
d is an integer greater than or equal to 1) The succinic anhydride group-containing cyclic organosiloxane according to claim 1, wherein a + b + c + d is an integer of 3 to 8. An adhesive aid using the succinic anhydride group-containing cyclic organosiloxane according to claim 1 or 2. (A) Polyorganosiloxane having two or more alkenyl groups bonded to a silicon atom in the molecule;
(C) Platinum-based catalyst; and (D) Succinic anhydride group-containing cyclic organosiloxane according to claim 1 or 2.
(B) An addition-curable silicone composition comprising a polyorganohydrogensiloxane having three or more hydrogen atoms directly bonded to a silicon atom in the molecule. An adhesive using the addition-curable silicone composition according to claim 4.