JP3865082B2 - Siloxane compound and process for producing the same - Google Patents

Description

〔ただし、式中のＲは炭素数１〜６のアルキル基、炭素数６〜１２のアリ−ル基、炭素数７〜１３のアラルキル基または炭素数７〜１３のアルカリ−ル基、Ｒ₁ は水素または炭素数１〜６のアルキル基、Ｒ₂ はカルボニル基、炭素数１〜６の分岐状もしくは線状アルキレン基または炭素数１〜６の分岐状もしくは線状オキシアルキレン基であり、Ｒ₂ がアルキレン基である場合にＲ₁ は水素、Ｒ₂ がオキシアルキレン基またはカルボニル基の場合にＲ₁ は炭素数１〜６のアルキル基、Ｒ₃ は炭素数１〜６のアルキル基または炭素数６〜１２のアリ−ル基、ａは０〜２の整数、ｂは０〜１の整数、ｃは０〜２０の整数、Ｑは下記一般式（Ｂ）
【化４】

（Ｒは上記と同じであり、Ｒ₄ は炭素数２〜１０の線状または分岐状アルキレン、f は１〜１００の整数）を意味する。〕
【０００６】
（２）両末端にヒドロシリル基を有するシロキサン化合物にアルケニルシランおよびアルケニルシロキサンを貴金属触媒の存在下に反応させる(1) 記載のシロキサン化合物の製造方法。
（３）両末端にアルケニル基を有するシロキサン化合物にヒドリドシロキサンおよびヒドリドシランを貴金属触媒の存在下に反応させる(1) 記載のシロキサン化合物の製造方法。
【０００７】
本発明の一般式（Ａ）で表されるシロキサン化合物は、下記反応式（Ｉ）で示されるように、両末端にヒドロシリル基を有するシロキサン化合物(i) とアルケニルシラン(ii)およびアルケニルシロキサン(iii) とを貴金属触媒の存在下にヒドロシリル化反応を行うことにより得られることができる。
【０００８】
【化５】

（ただし、式中のＲ、Ｒ₁ 、Ｒ₂ 、Ｒ₃ 、Ｒ₄ 、ａ、ｂ、ｃ、ｆおよびＱは一般式（Ａ）と同じであり、またＹはアルケニル基を意味する。）
【０００９】
反応式（Ｉ）に用いられる両末端にヒドロシリル基を有する化合物(i) としては、例えば、
【化６】

（式中のｈは２〜１００の整数、ｊ、ｋは１〜５０の整数を表す）が挙げられるが、これらに限定されるものではない。
【００１０】
反応式（Ｉ）に用いられるアルケニルシラン(ii)としては、例えば
ＣＨ₂ ＝ＣＨＳi(ＯＣＨ₃)₃
ＣＨ₂ ＝ＣＨＳi ＣＨ₃(ＯＣＨ₃)₂
ＣＨ₂ ＝ＣＨＳi(ＣＨ₃)₂ ＯＣＨ₃
ＣＨ₂ ＝ＣＨＳi(ＯＣＨ₂ ＣＨ₃)₃
ＣＨ₂ ＝ＣＨＳi ＣＨ₃(ＯＣＨ₂ ＣＨ₃)₂
ＣＨ₂ ＝ＣＨＳi(ＣＨ₃)₂ ＯＣＨ₂ ＣＨ₃
ＣＨ₂ ＝ＣＨＳi(ＯＣＨ₂ ＣＨ₃)₃
ＣＨ₂ ＝ＣＣＨ₃ Ｓi ＣＨ₃(ＯＣＨ₃)₂
ＣＨ₂ ＝ＣＨＣＨ₂ Ｓi(ＯＣＨ₃)₃
ＣＨ₂ ＝ＣＨＣＨ₂ Ｓi(ＯＣＨ₂ ＣＨ₃)₃
ＣＨ₂ ＝ＣＣＨ₃ ＣＨ₂ Ｓi(ＯＣＨ₂ ＣＨ₃)₃
ＣＨ₂ ＝ＣＨＳi(ＯＰｒ-i)₃
【００１１】
【化７】

等が挙げられるが、これらのうち、ＣＨ₂ ＝ＣＨＳi(ＯＣＨ₃)₃ 、ＣＨ₂ ＝ＣＨＳi(ＯＣＨ₂ ＣＨ₃)₃ が好ましい。
【００１２】
反応式（Ｉ）に用いられるアルケニルシロキサン(iii) としては、例えば、
ＣＨ₂ ＝ＣＨＳｉＣＨ₃ ＯＳi(ＣＨ₃)_{3 2}
ＣＨ₂ ＝ＣＨＳi ＯＳi(ＣＨ₃)_{3 3}
ＣＨ₂ ＝ＣＨＣＨ₂ Ｓi ＯＳi(ＣＨ₃)_{3 3}
【化８】

（ただし、式中のｃは一般式（Ａ）と同じである) が挙げられ、これらのうち好ましいのは、
【００１３】
【化９】

である。
【００１４】
前記反応式（Ｉ）において、両末端にヒドロシリル基を有するシロキサン化合物(i) に付加させるアルケニルシラン(ii)およびアルケニルシロキサン(iii) は、どちらを先に付加させても特に不具合はないが、蒸留精製が必要とされる場合には、その中間体の沸点において、より有利な順序が存在する場合もあり、適宜選定するのが好ましい。
【００１５】
また本発明の一般式（Ａ）で表されるシロキサン化合物は、下記反応式（II）で示されるように、両末端にアルケニルシリル基を有するシロキサン化合物(iv)とヒドリドシラン(v) およびヒドリドシロキサン(vi)とを貴金属触媒の存在下にヒドロシリル化反応を行うことにより得られることができる。
【００１６】
反応式（II）：
【化１０】

（ただし、式中のＲ、Ｒ₁ 、Ｒ₂ 、Ｒ₃ 、Ｒ₄ 、ａ、ｂ、ｃ、ｆおよびＱは一般式（Ａ）であり、またＹはアルケニル基を意味する。）
【００１７】
反応式（II）に用いられる両末端アルケニル基を有するシロキサン化合物(iv)としては上記した両末端にヒドロシリル基を有するシロキサン化合物(i) のＨをアルケニル基で置換したものを挙げることができる。またヒドリドシラン(v) としては上記したアルケニルシラン(ii)のアルケニル基をＨで置換したものを挙げることができる。またヒドリドシロキサン(vi)としては上記したアルケニルシロキサン(iii) のアルケニル基をＨで置換したものを挙げることができる。
【００１８】
反応式（Ｉ）および反応式（II）におけるヒドロシリル化反応は、貴金属触媒、特に白金触媒の存在下に円滑に進行する。白金触媒のうちでも、例えば塩化白金酸のイソプロピルアルコール溶液、１，２−ジビニルテトラメチルジシロキサン白金等が好ましく用いられる。
ヒドロシリル化反応は公知の条件で行うことができる。溶媒としては一般的なトルエン、ヘキサン等の有機溶剤を使用することもできるが、無溶媒でも特に不都合はない。反応温度は０〜２００℃が好ましく、より好適には３０〜１２０℃である。反応による発熱が大きい場合には、どちらか一方の原料を滴下することが好ましい。
ヒドロシリル化反応において、反応式（Ｉ）による場合には
【００１９】
【化１１】

【００２０】
反応式（II）による場合には
【化１２】

【００２１】
を中間体として経由するが、これら中間体は蒸留後次の反応に用いてもよく、また蒸留せずに反応粗液のまま次の反応に用いてもよい。
本発明のシロキサン化合物は、単独でまたは２種以上を併用することができ、例えば、プラスチック、金属、セラミック等の基材や線材上に造膜することにより、基材との密着性を向上させ、基材に防汚性や撥水性を付与することができる。
【００２２】
【発明の実施の形態】
以下、本発明を実施例により詳細に説明する。なお、例中の％は特に限定しない限り、重量％を意味する。
【実施例】
実施例１
（１）テトラメチルジシロキサンとビニルトリメトキシシランのヒドロシリル化反応
攪拌機、冷却管、温度計および滴下ロ−トを取り付けた５００ｍｌの四つ口フラスコに、テトラメチルジシロキサン２００ｇ（１．４９モル）を入れ、６０℃に昇温した。次いでビニルトリメトキシシラン２２０．７ｇ（１．４９モル）に、白金−ジビニルテトラメチルジシロキサン錯体の３％キシレン溶液７０μｌを添加した混合物を２００分かけて滴下し、滴下終了後７０℃以上で３０分攪拌を続けた後、冷却した。得られた生成物は、ＧＣ分析により下記（ａ）および（ｂ）の構造を有するものの混合体であり、目的生成物が６３％得られたことが確認された。
【００２３】
【化１３】

【００２４】
得られた反応液を減圧蒸留し、目的生成物が９９％以上 (ＧＣ分析により確認) の純度で２１６ｇ得られた。
また、減圧蒸留において留分を分け、ａ：ｂ＝９１．６：５．６（ＧＣ％）のものと、ａ：ｂ＝５４．３：４４．４（ＧＣ％）のものを、それぞれ ¹Ｈ−ＮＭＲ分析（９０ＭＨZ ；溶媒ＣＤＣｌ3 ）し、生成物（ａ）および（ｂ）の構造を確認した。それぞれのＮＭＲチャ−トを図１および２に示した。またこれらの生成物のＧＣ−ＭＳ分析の結果は以下の通りであった。
【００２５】
生成物（ａ）
ＣＩ−ＭＳ
２８１＝［Ｍ−Ｈ］⁺
２６７＝［Ｍ−ＣＨ₃］⁺
２５１＝［Ｍ−ＯＣＨ₃］⁺
２０７＝［ＳiＭｅ₂ＣＨ₂ＣＨ₂Ｓi（ＯＣＨ₃）₃］⁺
生成物（ｂ）
ＣＩ−ＭＳ
２８１＝［Ｍ−Ｈ］⁺
２６７＝［Ｍ−ＣＨ₃］⁺
２５１＝［Ｍ−ＯＣＨ₃］⁺
２０７＝［ＳiＭｅ₂ＣＨ₂ＣＨ₂Ｓi（ＯＣＨ₃）₃］⁺
【００２６】
（２）トリス（トリメチルシロキシ）ビニルシランと実施例１で得られた生成物のヒドロシリル化反応によるシロキサン化合物の合成
攪拌機、冷却管、温度計および滴下ロ−トを取り付けた３００ｍｌ四つ口フラスコに、実施例１で得られた生成物（Ａ：Ｂ＝６８．１：３１．６ ＧＣ％）７０．６ｇ（０．２５モル）を入れて７０℃に昇温した。次いでＧＣ純度９９％のトリス（トリメチルシロキシ）ビニルシラン８０．５ｇ（０．２５モル）と白金−ジビニルテトラメチルジシロキサン錯体の３％イソプロピルアルコ−ル溶液１３μｌの混合液を８５分かけて滴下し滴下終了後７０℃で２００分攪拌し、冷却した。得られたシロキサン化合物は、 ¹Ｈ−ＮＭＲ分析の結果、下記（ｃ）および（ｄ）の構造をとる化合物の混合体であることが確認された。この混合体のＮＭＲチャートを図３に示した。またＧＣ分析により目的生成物が９４％の純度で得られたことが確認された。
【００２７】
【化１４】

【００２８】
【発明の効果】
本発明のシロキサン化合物は、水の存在下に容易に反応または縮合する部位と、撥水性、撥油性等を有する部位とを合わせもち、優れた基材との密着性よび防汚性と撥水性を有するため、このシロキサン化合物を基材上に造膜することにより、造膜と基材との密着性が向上し、かつ基材に防汚性や撥水性を付与することができる。
【図面の簡単な説明】
【図１】実施例１で得られた生成物（ａ）の ¹Ｈ−ＮＭＲ分析チャート図である。
【図２】実施例１で得られた生成物（ｂ）の ¹Ｈ−ＮＭＲ分析チャート図である。
【図３】実施例１で得られたシロキサン化合物の ¹Ｈ−ＮＭＲ分析チャート図である。[0001]
BACKGROUND OF THE INVENTION
The present invention relates to a siloxane compound and a method for producing the same, and more particularly to a novel siloxane compound having excellent adhesion to a substrate and excellent in antifouling properties and water repellency and a method for producing the same.
[0002]
[Prior art]
Conventionally, silane coupling agents have been used for surface treatment of metals, glass, resins, wood, concrete, and the like for the purpose of imparting antifouling properties and water repellency. For example, JP-A-2-99582 JP-A-2-70787, JP-A-2-16186, JP-A-1-290209 and the like mainly propose alkylsilanes. The effect of imparting water repellency by a coupling agent is useful, and various developments are underway. For example, Surface Science, 21 , 10, 48 (1983). Has proposed a fluoroalkyl group-substituted silane coupling agent capable of introducing not only an alkyl group but also other substituents to improve its performance. However, there are few studies to introduce other substituents, and development of a new surface treatment agent is desired.
[0003]
[Problems to be solved by the invention]
An object of the present invention is to provide excellent adhesion to a substrate and excellent antifouling properties and repellency, including a portion that easily reacts or condenses in the presence of water and a portion that has water repellency, oil repellency, and the like. It is an object of the present invention to provide a novel siloxane compound having water and a method for producing the same.
[0004]
[Means for Solving the Problems]
In view of the above problems, the present inventor has intensively studied paying attention to a trialkylsiloxy group as a substituent that imparts water repellency and antifouling properties. The present inventors have found that a novel siloxane compound having a site that adheres by chemical bonding and a trialkylsiloxy group having water repellency, oil repellency, and antifouling properties can be obtained.
[0005]
The invention claimed in the present invention is as follows.
(1) A siloxane compound represented by the following general formula (A).
[Chemical 3]

[In the formula, R is an alkyl group having 1 to 6 carbon atoms, an aryl group having 6 to 12 carbon atoms, an aralkyl group having 7 to 13 carbon atoms, or an alkali group having 7 to 13 carbon atoms, R _1; Is hydrogen or an alkyl group having 1 to 6 carbon atoms, R ₂ is a carbonyl group, a branched or linear alkylene group having 1 to 6 carbon atoms, or a branched or linear oxyalkylene group having 1 to 6 carbon atoms; ₂ R ₁ when it is an alkylene group of hydrogen, R ₁ if R ₂ is an oxyalkylene group or a carbonyl group is an alkyl group having 1 to 6 carbon atoms, R ₃ is 1 to 6 carbon atoms alkyl group or a C An aryl group of formulas 6 to 12, a is an integer of 0 to 2, b is an integer of 0 to 1, c is an integer of 0 to 20, and Q is the following general formula (B)
[Formula 4]

(R is the same as above, R ₄ is a linear or branched alkylene having 2 to 10 carbon atoms, and f is an integer of 1 to 100). ]
[0006]
(2) The method for producing a siloxane compound according to (1), wherein the siloxane compound having hydrosilyl groups at both ends is reacted with alkenylsilane and alkenylsiloxane in the presence of a noble metal catalyst.
(3) The method for producing a siloxane compound according to (1), wherein a siloxane compound having an alkenyl group at both ends is reacted with hydridosiloxane and hydridosilane in the presence of a noble metal catalyst.
[0007]
As shown in the following reaction formula (I), the siloxane compound represented by the general formula (A) of the present invention includes a siloxane compound (i) having hydrosilyl groups at both ends, an alkenylsilane (ii), and an alkenylsiloxane ( iii) can be obtained by performing a hydrosilylation reaction in the presence of a noble metal catalyst.
[0008]
[Chemical formula 5]

(However, R, R ₁ , R ₂ , R ₃ , R ₄ , a, b, c, f and Q in the formula are the same as those in the general formula (A), and Y means an alkenyl group.)
[0009]
Examples of the compound (i) having hydrosilyl groups at both ends used in the reaction formula (I) include:
[Chemical 6]

(Wherein h represents an integer of 2 to 100 and j and k represent an integer of 1 to 50), but are not limited thereto.
[0010]
Examples of the alkenylsilane (ii) used in the reaction formula (I) include CH ₂ ═CHSi (OCH ₃ ) _3.
CH ₂ = CHSi CH ₃ (OCH ₃ ) ₂
CH ₂ = CHSi (CH ₃ ) ₂ OCH ₃
CH ₂ = CHSi (OCH ₂ CH ₃ ) ₃
CH ₂ = CHSi CH ₃ (OCH ₂ CH ₃ ) ₂
CH ₂ = CHSi (CH ₃ ) ₂ OCH ₂ CH ₃
CH ₂ = CHSi (OCH ₂ CH ₃ ) ₃
CH ₂ = CCH ₃ Si CH ₃ (OCH ₃ ) ₂
CH ₂ = CHCH ₂ Si (OCH ₃ ) ₃
CH ₂ = CHCH ₂ Si (OCH ₂ CH ₃ ) ₃
CH ₂ = CCH ₃ CH ₂ Si (OCH ₂ CH ₃ ) ₃
CH ₂ = CHSi (OPr-i) ₃
[0011]
[Chemical 7]

Of these, CH ₂ ═CHSi (OCH ₃ ) ₃ and CH ₂ ═CHSi (OCH ₂ CH ₃ ) ₃ are preferable.
[0012]
Examples of the alkenylsiloxane (iii) used in the reaction formula (I) include:
CH ₂ = CHSiCH ₃ OSi (CH ₃ ) _{3 2}
CH ₂ = CHSi OSi (CH ₃ ) _{3 3}
CH ₂ = CHCH ₂ Si OSi (CH ₃ ) _{3 3}
[Chemical 8]

(However, c in the formula is the same as in the general formula (A)). Among these, preferred is
[0013]
[Chemical 9]

It is.
[0014]
In the above reaction formula (I), the alkenylsilane (ii) and the alkenylsiloxane (iii) to be added to the siloxane compound (i) having hydrosilyl groups at both ends are not particularly defective regardless of which one is added first. When distillation purification is required, a more advantageous order may exist in the boiling point of the intermediate, and it is preferable to select appropriately.
[0015]
In addition, the siloxane compound represented by the general formula (A) of the present invention includes a siloxane compound (iv) having alkenylsilyl groups at both ends, hydridosilane (v), and hydride as represented by the following reaction formula (II): It can be obtained by subjecting siloxane (vi) to a hydrosilylation reaction in the presence of a noble metal catalyst.
[0016]
Reaction formula (II):
Embedded image

(In the formula, R, R ₁ , R ₂ , R ₃ , R ₄ , a, b, c, f and Q are the general formula (A), and Y means an alkenyl group.)
[0017]
Examples of the siloxane compound (iv) having both alkenyl groups used in the reaction formula (II) include those obtained by substituting H of the siloxane compound (i) having hydrosilyl groups at both ends with alkenyl groups. Examples of the hydridosilane (v) include those obtained by substituting the alkenyl group of the alkenylsilane (ii) with H. Examples of the hydridosiloxane (vi) include those obtained by substituting the alkenyl group of the alkenylsiloxane (iii) with H.
[0018]
The hydrosilylation reaction in the reaction formulas (I) and (II) proceeds smoothly in the presence of a noble metal catalyst, particularly a platinum catalyst. Among the platinum catalysts, for example, isopropyl alcohol solution of chloroplatinic acid, 1,2-divinyltetramethyldisiloxane platinum and the like are preferably used.
The hydrosilylation reaction can be performed under known conditions. A general organic solvent such as toluene or hexane can be used as the solvent, but there is no particular problem even if no solvent is used. The reaction temperature is preferably 0 to 200 ° C, more preferably 30 to 120 ° C. When the heat generated by the reaction is large, it is preferable to drop one of the raw materials.
In the hydrosilylation reaction, according to the reaction formula (I),
Embedded image

[0020]
In the case of reaction formula (II):

[0021]
These intermediates may be used in the next reaction after distillation, or may be used in the next reaction as the reaction crude liquid without distillation.
The siloxane compound of the present invention can be used alone or in combination of two or more. For example, by forming a film on a base material or wire such as plastic, metal, ceramic, etc., the adhesion to the base material is improved. Further, antifouling property and water repellency can be imparted to the substrate.
[0022]
DETAILED DESCRIPTION OF THE INVENTION
Hereinafter, the present invention will be described in detail with reference to examples. In the examples, “%” means “% by weight” unless otherwise specified.
【Example】
Example 1
(1) Tetramethyldisiloxane and vinyltrimethoxysilane hydrosilylation reaction stirrer, condenser, thermometer, and 500 ml four-necked flask equipped with a dropping funnel were charged with 200 g (1.49 mol) of tetramethyldisiloxane. The temperature was raised to 60 ° C. Next, a mixture obtained by adding 70 μl of a 3% xylene solution of a platinum-divinyltetramethyldisiloxane complex to 220.7 g (1.49 mol) of vinyltrimethoxysilane was added dropwise over 200 minutes. After stirring for a minute, it was cooled. The obtained product was a mixture of those having the following structures (a) and (b) by GC analysis, and it was confirmed that 63% of the desired product was obtained.
[0023]
Embedded image

[0024]
The obtained reaction solution was distilled under reduced pressure to obtain 216 g of a target product with a purity of 99% or more (confirmed by GC analysis).
Further, the fractions were separated by distillation under reduced pressure, and those having a: b = 91.6: 5.6 (GC%) and those having a: b = 54.3: 44.4 (GC%) were each ¹ 1 H-NMR analysis (90 MHz; solvent CDCl 3) confirmed the structure of products (a) and (b). The respective NMR charts are shown in FIGS. The results of GC-MS analysis of these products were as follows.
[0025]
Product (a)
CI-MS
281 = [M−H] ⁺
267 = [M-CH ₃ ] ⁺
251 = [M-OCH ₃ ] ⁺
207 = [SiMe ₂ CH ₂ CH ₂ Si (OCH ₃ ) ₃ ] ⁺
Product (b)
CI-MS
281 = [M−H] ⁺
267 = [M-CH ₃ ] ⁺
251 = [M-OCH ₃ ] ⁺
207 = [SiMe ₂ CH ₂ CH ₂ Si (OCH ₃ ) ₃ ] ⁺
[0026]
(2) Synthesis of a siloxane compound by hydrosilylation reaction of tris (trimethylsiloxy) vinylsilane and the product obtained in Example 1 70.6 g (0.25 mol) of the product obtained in Example 1 (A: B = 68.1: 31.6 GC%) was added, and the temperature was raised to 70 ° C. Next, a mixed solution of 80.5 g (0.25 mol) of tris (trimethylsiloxy) vinylsilane having a GC purity of 99% and 13 μl of a 3% isopropyl alcohol solution of platinum-divinyltetramethyldisiloxane complex was dropped over 85 minutes. After completion, the mixture was stirred at 70 ° C. for 200 minutes and cooled. As a result of ¹ H-NMR analysis, the obtained siloxane compound was confirmed to be a mixture of compounds having the following structures (c) and (d). The NMR chart of this mixture is shown in FIG. GC analysis confirmed that the desired product was obtained with a purity of 94%.
[0027]
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[0028]
【The invention's effect】
The siloxane compound of the present invention has a portion that easily reacts or condenses in the presence of water and a portion having water repellency, oil repellency, etc., and has excellent adhesion to the substrate and antifouling and water repellency. Therefore, by forming a film of this siloxane compound on the substrate, the adhesion between the film formation and the substrate can be improved, and antifouling properties and water repellency can be imparted to the substrate.
[Brief description of the drawings]
1 is a ¹ H-NMR analysis chart of a product (a) obtained in Example 1. FIG.
2 is a chart of ¹ H-NMR analysis of a product (b) obtained in Example 1. FIG.
3 is a ¹ H-NMR analysis chart of the siloxane compound obtained in Example 1. FIG.

Claims (3)

A siloxane compound represented by the following general formula (A):

[In the formula, R is an alkyl group having 1 to 6 carbon atoms, an aryl group having 6 to 12 carbon atoms, an aralkyl group having 7 to 13 carbon atoms, or an alkali group having 7 to 13 carbon atoms, R _1; Is hydrogen or an alkyl group having 1 to 6 carbon atoms, R ₂ is a carbonyl group, a branched or linear alkylene group having 1 to 6 carbon atoms, or a branched or linear oxyalkylene group having 1 to 6 carbon atoms; ₂ R ₁ when it is an alkylene group of hydrogen, R ₁ if R ₂ is an oxyalkylene group or a carbonyl group is an alkyl group having 1 to 6 carbon atoms, R ₃ is 1 to 6 carbon atoms alkyl group or a C An aryl group of formulas 6 to 12, a is an integer of 0 to 2, b is an integer of 0 to 1, c is an integer of 0 to 20, and Q is the following general formula (B)

(R is the same as above, R ₄ is a linear or branched alkylene having 2 to 10 carbon atoms, and f is an integer of 1 to 100). ] The method for producing a siloxane compound according to claim 1, wherein the siloxane compound having hydrosilyl groups at both ends is reacted with alkenylsilane and alkenylsiloxane in the presence of a noble metal catalyst. 2. The method for producing a siloxane compound according to claim 1, wherein a siloxane compound having alkenyl groups at both ends is reacted with hydridosiloxane and hydridosilane in the presence of a noble metal catalyst.

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