JP3894099B2 - Flame retardant silicone rubber composition - Google Patents

Description

（式中、Ｒ¹は同一又は異なってもよく、水素原子又は炭素数１〜８の非置換１価炭化水素基、ｎは２〜４の整数、ｍは０又は１以上の整数を示す。）
を白金原子に対して分子内の窒素原子の比率で１〜２００倍モルになる量
（ｅ）有機過酸化物 ０．１〜１０重量部
を含有してなることを特徴とする難燃性シリコーンゴム組成物を提供する。
【０００７】
以下、本発明につき更に詳しく説明する。
本発明において、ベース成分として使用される（ａ）オルガノポリシロキサンは、下記平均組成式（１）
Ｒ_aＳｉＯ_(4-a)/2 …（１）
で示されるものである。
【０００８】
ここで、Ｒは、具体的には、メチル基、エチル基、プロピル基、ブチル基等のアルキル基、シクロヘキシル基等のシクロアルキル基、ビニル基、アリル基、ブテニル基、ヘキセニル基等のアルケニル基、フェニル基、トリル基等のアリール基、ベンジル基、フェニルエチル基等のアラルキル基、又はこれらの基の炭素原子に結合した水素原子の一部又は全部をハロゲン原子、シアノ基などで置換したクロロメチル基、トリフルオロプロピル基、シアノエチル基などから選択される同一又は異種の、好ましくは炭素数１〜１０、より好ましくは炭素数１〜８の非置換又は置換の１価炭化水素基を示す。これらの中でも、メチル基、フェニル基、ビニル基が好ましく、メチル基がＲの５０モル％以上、特に８０モル％以上であることが好ましい。Ｒは脂肪族不飽和基（アルケニル基）を含んでいなくともよいが、脂肪族不飽和基（アルケニル基）を少なくとも２個有していることが好ましい。この場合、Ｒ中の脂肪族不飽和基の含有量は０．００１〜２０モル％、特に０．０２５〜５モル％であることが好ましい。また、ａは１．９０〜２．０５の正数である。
【０００９】
上記式（１）のオルガノポリシロキサンは、基本的には直鎖状であることが好ましいが、分子構造の異なる１種又は２種以上の混合物であってもよい。更に、その平均重合度が１００〜２０，０００、特に３，０００〜１０，０００であることが好ましい。
【００１０】
本発明で用いる（ｂ）シリカ充填剤としては、シリコーンゴムに適度の硬さと引っ張り強さ等の機械的強度を向上させるために、比表面積が少なくとも５０ｍ²／ｇ以上、好ましくは１００〜４００ｍ²／ｇの補強性シリカが使用される。このようなシリカとしては、ヒュームドシリカ、焼成シリカ、沈降シリカ等が単独又は２種以上の組み合わせで用いられる。好ましくはヒュームドシリカである。また、これらのシリカは、鎖状オルガノポリシロキサン、環状オルガノポリシロキサン、ヘキサメチルジシラザン、ジクロルジメチルシラン等で表面処理したものでもよい。かかるシリカは、（ａ）成分のオルガノポリシロキサン１００重量部に対して５〜１００重量部、好ましくは１０〜５０重量部の割合で配合され、これより多く配合されても、また少なく配合されても、シリコーンゴムの加工性が悪くなってしまったり、十分な機械的強度が得られ難くなってしまう。
【００１１】
（ｃ）成分の白金化合物は、アルコール変性塩化白金酸、塩化白金酸とオレフィンとの錯体、塩化白金酸とジビニルテトラメチルシロキサンとの錯体等が挙げられる。
【００１２】
この白金化合物の配合量は、白金金属として（ａ）、（ｂ）成分の合計量に対し１〜５００ｐｐｍ、特に５〜２００ｐｐｍである。その量が少なすぎると難燃性に十分な効果を発揮せず、多すぎても効果の更なる向上はなく、経済的に不利となる。
【００１３】
（ｄ）成分のアミン化合物は、下記一般式（２）で示される。
【化４】

（Ｒ¹は同一又は異なってもよく、水素原子又は炭素数１〜８の非置換１価炭化水素基、ｎは２〜４の整数、ｍは０又は１以上の整数を示す。）
【００１４】
ここで、Ｒ¹は水素原子又は炭素数１〜８、好ましくは水素原子、炭素数１〜２の非置換１価炭化水素基を示し、ｎは２〜４、好ましくは２又は３、特に好ましくは２であり、ｍは０又は１以上、好ましくは０〜５、特に好ましくは０〜３の整数である。
【００１５】
上記式（２）のアミン化合物は、その１種を単独で使用しても２種以上を組み合わせて用いるようにしてもよいが、上記式（２）の化合物の配合により、これらの分子内の窒素原子が白金原子を弱く被毒することにより白金を保護し、よってシリコーンゴムの難燃性を高めると考えられる。また、置換基Ｒ¹はより好ましくは水素原子であり、炭化水素基の場合、炭素数が３以上でかさ高くなると、白金への被毒作用が弱まり、難燃性への効果は少なくなるおそれがあるので、メチル基又はエチル基が好ましい。
代表例としては、エチレンジアミン、ジエチレントリアミン、トリエチレンテトラミン、テトラエチレンペンタミン、プロピレンジアミン、ジプロピレントリアミン、ブチレンジアミン、ジブチレントリアミンなどが挙げられ、ジエチレントリアミン、トリエチレンテトラミン、テトラエチレンペンタミン、ジプロピレントリアミンが好ましい。
【００１６】
上記（ｄ）成分の配合量は、白金原子に対して分子内の窒素原子の比率で１〜２００倍モルになる量であり、より好ましくは１０〜１００倍モルである。１倍モル未満だと難燃性の効果が十分でなく、また２００倍モルを超えると白金への被毒が強すぎてかえって難燃性を悪化させる。
【００１７】
（ｅ）成分の硬化剤としては、有機過酸化物が用いられる。
【００１８】
有機過酸化物としては、有機過酸化物硬化型シリコーンゴム組成物の架橋剤として用いられるいずれのものであってもよく、従来公知のものを使用することができる。例えば、ベンゾイルパーオキサイド、２，４−ジクロロベンゾイルパーオキサイド、ｐ−メチルベンゾイルパーオキサイド、ｏ−メチルベンゾイルパーオキサイド、２，４−ジクミルパーオキサイド、２，５−ジメチル−ビス（２，５−ｔ−ブチルパーオキシ）ヘキサン、ジ−ｔ−ブチルパーオキサイド、ｔ−ブチルパーベンゾエート、１，１−ビス（ｔ−ブチルパーオキシカルボキシ）ヘキサン等が挙げられるが、特にこれらに限定されるものではない。
【００１９】
なお、有機過酸化物の添加量は触媒量であり、硬化速度に応じて適宜選択すればよいが、通常は（ａ）成分１００重量部に対して０．１〜１０重量部、好ましくは０．２〜３重量部の範囲とすることができる。
【００２５】
また、本発明のシリコーンゴム組成物には、（ｆ）成分として、下記一般式（４）
【化５】

（式中、Ｒ²は同一又は異なってもよく、メチル基、ビニル基又はフェニル基、ｋは１〜５０、好ましくは１〜３０の整数を示す。）
で表される化合物を配合することが好ましい。これにより、組成物の加工性が著しく向上すると共に、各成分の分散性が向上する。（ｆ）成分は（ａ）成分１００重量部に対し、０．１〜２０重量部、特に０．５〜１０重量部配合することが好ましい。
【００２６】
なお、本発明のシリコーンゴム組成物には、必要に応じ、ヒュームド酸化チタン等の難燃剤、炭酸カルシウムのような充填剤、補強剤となるシリコーン系のレジン、カーボンブラック、導電性亜鉛華、金属粉等の導電剤、アセチレン化合物、リン化合物、ニトリル化合物、カルボキシレート、錫化合物、水銀化合物、硫黄化合物等のヒドロシリル化反応制御剤、酸化鉄、酸化セリウムのような耐熱剤、ジメチルシリコーンオイル等の内部離型剤、接着性付与剤、チクソ性付与剤等を本発明の効果を損なわない範囲で任意に配合することができる。
【００２７】
本発明のシリコーンゴム組成物の製造方法は、特に制限されないが、（ａ）〜（ｃ）成分を公知の方法でコンパウンドした後に、ローラーミルやバンバリーミキサー等で（ｄ）成分を混練り添加する方法などを採用することができる。また、（ｄ）成分をシリコーンオイル、アルコール等で希釈したものを添加してもよい。その後、任意の加硫剤成分を添加し、公知の方法で加熱硬化すればよい。
【００２８】
このようにして得られたシリコーンゴム組成物は、射出成形、注型成形、金型加圧成形、押出成形などの種々の成形法によって必要とされるシリコーンゴムに成形することができる。
【００２９】
なお、硬化条件は適宜調整することができるが、８０〜２００℃、好ましくは１００〜１８０℃で、５秒〜６０分、好ましくは２０秒〜３０分程度とすることが好適である。
【００３０】
このようにして得られるシリコーンゴム硬化物は、良好な難燃性を有するために建築部材、電線材、電気部品等に好適である。
【００３１】
【実施例】
以下、実施例及び比較例を示し、本発明を具体的に説明するが、本発明は下記の実施例に制限されるものではない。なお、下記例で部は重量部を示す。
【００３２】
［実施例１，２、比較例１，２］
（ａ）成分のポリオルガノシロキサンとして、（ＣＨ₃）₂ＳｉＯ単位９９．８５モル％、（ＣＨ₃）（ＣＨ₂＝ＣＨ）ＳｉＯ単位０．１５モル％からなり、分子鎖末端が（ＣＨ₂＝ＣＨ）（ＣＨ₃）₂ＳｉＯ単位で封鎖された重合度が約７０００のメチルビニルポリシロキサン生ゴムを使用し、このメチルビニルポリシロキサン生ゴム１００部、比表面積が２００ｍ²／ｇのヒュームドシリカ２５部、分散剤として分子鎖末端に水酸基を含有するジメチルポリシロキサン（重合度１０）１部及び分子両末端に水酸基を含有するメチルビニルポリシロキサン（重合度１５、全有機基に対するビニル基含有量５モル％）３部をニーダー中で均一に混合し、１５０℃で２時間熱処理を行った。このコンパウンドに難燃助剤として四酸化三鉄ＫＮ３２０（戸田工業（株）製）３部及び酸化チタンＰ−２５（日本アエロジル（株）製）２部及び結晶性シリカクリスタライトＶＸＳ（（株）龍森製）４０部、更にエタノール変性塩化白金酸（白金含有量２ｗｔ％）を０．１部、２本ロールにて添加してベース（１）を得た。
【００３３】
次に、ジエチレントリアミン及びトリエチレンテトラミンの１０ｗｔ％エタノール溶液を作製し、上記で作製したシリコーンベース（１）１００部にそれぞれ０．０８部及び０．１部をロールにて添加した［実施例１，２］。
【００３４】
比較例として、ベース（１）にエタノールを０．１部添加し［比較例１］、更にベンゾトリアゾールの１０ｗｔ％エタノール溶液を０．０８部添加したもの［比較例２］を用意した。
【００３５】
これらの組成物に、それぞれ２，５−ビス（ｔ−ブチルパーオキシ）−２，５−ジメチルヘキサン０．５部を加えた後、１７０℃×１０分間、プレスキュアした後、２００℃×２４０分間アフターキュアして０．８ｍｍ厚のシート状の成形物を得た。このシートに関してＵＬ９４にて定められた方法で難燃秒数を計測した。
【００３６】
【表１】

【００３７】
［実施例３、比較例３，４］
ジプロピレントリアミンをエタノールにて１０ｗｔ％溶液とした。この溶液を実施例１のベース１００部に対して、それぞれ０．００１部［比較例３］、０．０９７部［実施例３］、０．９６６部［比較例４］添加した。
【００３８】
【表２】

【００３９】
【発明の効果】
本発明によれば、シリコーンゴム組成物に白金化合物と特定のアミン化合物を添加混合することにより、優れた難燃性を持った硬化物（シリコーンゴム）を与えるシリコーンゴム組成物を得ることが出来る。[0001]
BACKGROUND OF THE INVENTION
The present invention relates to a flame retardant silicone rubber composition which gives a cured product (silicone rubber) having improved flame retardancy and can be suitably used in the fields of electrical, electronic parts, automobile parts and the like.
[0002]
[Prior art]
Silicone rubber has advantages such as heat resistance, weather resistance, durability, releasability, electrical characteristics, etc., so it has been processed into various shapes from the past and has been processed into electrical / electronic related parts, automobile parts, OA, equipment. It is used in various fields such as parts and building materials. In this case, various additives are added to the silicone rubber to impart flame retardancy. As a method for imparting flame retardancy to such a silicone rubber composition, a platinum compound is generally used as a flame retardant. However, platinum compounds alone are not sufficient, and various auxiliaries are considered. For example, carbon black is mentioned in US Pat. No. 3,652,488, and titanium oxide is mentioned in US Pat. No. 3,635,874. Japanese Patent Publication No. 51-24301 uses a method of adding black bengara (FeO) _x (FeO ₃ ) _y , and black bengara (Fe ₃ O ₄ ) is particularly effective. However, these methods have the disadvantages that the compound has to be colored and that the difficulty changes with time. Japanese Patent Publication No. 53-16019 proposes blending a triazole compound such as benzotriazole, but the flame retardancy is not sufficient.
[0003]
[Patent Document 1]
US Pat. No. 3,652,488 [Patent Document 2]
US Pat. No. 3,635,874 [Patent Document 3]
Japanese Patent Publication No. 51-24301 [Patent Document 4]
Japanese Patent Publication No. 53-16019 [0004]
[Problems to be solved by the invention]
This invention is made | formed in view of the said situation, and it aims at providing the silicone rubber composition which gives the hardened | cured material which has the outstanding flame retardance.
[0005]
Means for Solving the Problem and Embodiment of the Invention
As a result of intensive studies to achieve the above object, the present inventors have found that flame retardancy can be greatly improved by using an amine compound represented by the following general formula (2) in combination with a platinum compound. The present invention has been made.
[0006]
Therefore, the present invention
(A) The following average composition formula (1)
R _a SiO _{(4-a) / 2} (1)
(In the formula, R is the same or different unsubstituted or substituted monovalent hydrocarbon group, and a is a positive number of 1.90 to 2.05.)
100 parts by weight of an organopolysiloxane represented in (b) reinforcing silica having a specific surface area of at least 50 m ² / g
5 to 100 parts by weight (c) Platinum compound in an amount of 1 to 500 ppm of platinum in terms of platinum amount (a) and (b) in terms of platinum amount (d) The following general formula (2) One or more selected from amine compounds

(In the formula, R ¹ is may be the same or different, unsubstituted monovalent hydrocarbon group hydrogen atom or a C1-8, n represents an integer from 2 to 4, m a is 0 or an integer of 1 or more. )
And (e) 0.1 to 10 parts by weight of an organic peroxide in an amount of 1 to 200 moles in terms of the ratio of nitrogen atoms in the molecule to platinum atoms. A flame retardant silicone rubber composition is provided.
[0007]
Hereinafter, the present invention will be described in more detail.
In the present invention, the organopolysiloxane (a) used as the base component has the following average composition formula (1)
R _a SiO _{(4-a) / 2} (1)
It is shown by.
[0008]
Here, R is specifically an alkyl group such as a methyl group, an ethyl group, a propyl group or a butyl group, a cycloalkyl group such as a cyclohexyl group, an alkenyl group such as a vinyl group, an allyl group, a butenyl group or a hexenyl group. A phenyl group, an aryl group such as a tolyl group, an aralkyl group such as a benzyl group or a phenylethyl group, or a chloro group in which some or all of the hydrogen atoms bonded to the carbon atoms of these groups are substituted with a halogen atom, a cyano group, or the like. An unsubstituted or substituted monovalent hydrocarbon group having the same or different, preferably 1 to 10 carbon atoms, more preferably 1 to 8 carbon atoms, selected from a methyl group, a trifluoropropyl group, a cyanoethyl group and the like is shown. Of these, methyl group, phenyl group, vinyl group are preferable, methyl group is more than 50 mol% of R, is preferably in particular 80 mol% or more. R may not contain an aliphatic unsaturated group (alkenyl group), but preferably has at least two aliphatic unsaturated groups (alkenyl groups). In this case, the content of the aliphatic unsaturated group in R is preferably 0.001 to 20 mol%, particularly preferably 0.025 to 5 mol%. Moreover, a is a positive number of 1.90 to 2.05.
[0009]
The organopolysiloxane of the above formula (1) is basically preferably linear, but may be one or a mixture of two or more having different molecular structures. Further, the average degree of polymerization is preferably 100 to 20,000, particularly 3,000 to 10,000.
[0010]
The (b) a silica filler used in the present invention, in order to improve the mechanical strength of the strength such as tensile and hardness of moderate to silicone rubber, the specific surface area of at least 50 m ² / g or more, preferably 100 to 400 m ² / G reinforcing silica is used. As such silica, fumed silica, calcined silica, precipitated silica, or the like is used alone or in combination of two or more. Fumed silica is preferred. These silicas may be surface-treated with chain organopolysiloxane, cyclic organopolysiloxane, hexamethyldisilazane, dichlorodimethylsilane or the like. Such silica is blended in a proportion of 5 to 100 parts by weight, preferably 10 to 50 parts by weight, based on 100 parts by weight of the organopolysiloxane of component (a), and even if blended more than this, it is blended in a small amount. However, the processability of the silicone rubber is deteriorated, and it is difficult to obtain sufficient mechanical strength.
[0011]
Examples of the platinum compound as component (c) include alcohol-modified chloroplatinic acid, a complex of chloroplatinic acid and olefin, a complex of chloroplatinic acid and divinyltetramethylsiloxane, and the like.
[0012]
The compounding quantity of this platinum compound is 1-500 ppm with respect to the total amount of (a) and (b) component as a platinum metal, especially 5-200 ppm. If the amount is too small, a sufficient effect on flame retardancy will not be exhibited. If the amount is too large, the effect will not be further improved, which is economically disadvantageous.
[0013]
The amine compound as component (d) is represented by the following general formula (2).
[Formula 4]

(R ¹ may be the same or different, an unsubstituted monovalent hydrocarbon group hydrogen atom or a C1-8, n represents an integer of 2 to 4, m is 0 or an integer of 1 or more.)
[0014]
Here, R ¹ represents a hydrogen atom or an unsubstituted monovalent hydrocarbon group having 1 to 8 carbon atoms, preferably a hydrogen atom or 1 to 2 carbon atoms, and n is 2 to 4, preferably 2 or 3, particularly preferably. Is 2, and m is 0 or 1 or more, preferably 0 to 5, particularly preferably an integer of 0 to 3.
[0015]
The amine compound of the above formula (2) may be used alone or in combination of two or more thereof. However, depending on the compound of the above formula (2), It is thought that the nitrogen atom weakly poisons the platinum atom, thereby protecting the platinum and thus enhancing the flame retardancy of the silicone rubber. Further, the substituent R ¹ is more preferably a hydrogen atom, and in the case of a hydrocarbon group, if the carbon number is 3 or more, the poisoning action to platinum is weakened, and the effect on flame retardancy may be reduced. Therefore, a methyl group or an ethyl group is preferable.
Representative examples include ethylenediamine, diethylenetriamine, triethylenetetramine, tetraethylenepentamine, propylenediamine, dipropylenetriamine, butylenediamine, dibutylenetriamine, and the like, and diethylenetriamine, triethylenetetramine, tetraethylenepentamine, dipropylenetriamine. Is preferred.
[0016]
The blending amount of the component (d) is an amount that is 1 to 200 times mol, more preferably 10 to 100 times mol in terms of the ratio of nitrogen atoms in the molecule to platinum atoms. If it is less than 1 mol, the flame retardancy effect is not sufficient, and if it exceeds 200 mol, the poisoning to platinum is too strong, and the flame retardance is worsened.
[0017]
(E) The curing agent component, an organic peroxide is used.
[0018]
The organic peroxide may be any of those used as a crosslinking agent for organic peroxide-curable silicone rubber compositions, and conventionally known ones can be used. For example, benzoyl peroxide, 2,4-dichlorobenzoyl peroxide, p-methylbenzoyl peroxide, o-methylbenzoyl peroxide, 2,4-dicumyl peroxide, 2,5-dimethyl-bis (2,5- t-butylperoxy) hexane, di-t-butylperoxide, t-butylperbenzoate, 1,1-bis (t-butylperoxycarboxy) hexane, and the like, but are not particularly limited thereto. Absent.
[0019]
The addition amount of the organic peroxide is a catalyst amount and may be appropriately selected according to the curing rate. Usually, it is 0.1 to 10 parts by weight, preferably 0 with respect to 100 parts by weight of component (a). .2 to 3 parts by weight.
[0025]
Also, the silicone rubber composition of the present invention, as component (f), the following general formula (4)
[Chemical formula 5]

(Wherein, R ² may be the same or different, a methyl group, vinyl group or phenyl group, k is 1 to 50, preferably an integer of 1 to 30.)
It is preferable to mix | blend the compound represented by these. Thereby, the workability of the composition is remarkably improved and the dispersibility of each component is improved. (F) It is preferable to mix | blend 0.1-20 weight part with respect to 100 weight part of (a) component, especially 0.5-10 weight part.
[0026]
The silicone rubber composition of the present invention includes a flame retardant such as fumed titanium oxide, a filler such as calcium carbonate, a silicone resin that serves as a reinforcing agent, carbon black, conductive zinc white, metal Conductive agent such as powder, acetylene compound, phosphorus compound, nitrile compound, carboxylate, tin compound, mercury compound, sulfur compound and other hydrosilylation reaction control agent, iron oxide, heat resistant agent such as cerium oxide, dimethyl silicone oil, etc. An internal mold release agent, an adhesiveness imparting agent, a thixotropic property imparting agent and the like can be arbitrarily blended within a range not impairing the effects of the present invention.
[0027]
The method for producing the silicone rubber composition of the present invention is not particularly limited, but after the components (a) to (c) are compounded by a known method, the component (d) is kneaded and added using a roller mill or a Banbury mixer. A method etc. can be adopted. Moreover, you may add what diluted (d) component with silicone oil, alcohol, etc. FIG. Thereafter, an arbitrary vulcanizing agent component may be added and heat-cured by a known method.
[0028]
The silicone rubber composition thus obtained can be molded into the required silicone rubber by various molding methods such as injection molding, cast molding, mold pressure molding, and extrusion molding.
[0029]
In addition, although hardening conditions can be adjusted suitably, it is 80-200 degreeC, Preferably it is 100-180 degreeC, 5 seconds-60 minutes, Preferably it is about 20 seconds-30 minutes.
[0030]
The silicone rubber cured product thus obtained is suitable for building members, electric wire materials, electrical parts and the like because it has good flame retardancy.
[0031]
【Example】
EXAMPLES Hereinafter, although an Example and a comparative example are shown and this invention is demonstrated concretely, this invention is not restrict | limited to the following Example. In the following examples, parts indicate parts by weight.
[0032]
[Examples 1 and 2, Comparative Examples 1 and 2]
(A) as a component of the polyorganosiloxane, (CH _{3) 2} SiO units 99.85 _{mol%, (CH 3) (CH} 2 = CH) of SiO units 0.15 mol%, the molecular chain ends (CH ₂ = CH) (CH ₃ ) ₂ SiO united methyl vinyl polysiloxane raw rubber having a degree of polymerization of about 7000, 100 parts of this methyl vinyl polysiloxane raw rubber, fumed silica 25 having a specific surface area of 200 m ² / g 1 part of dimethylpolysiloxane containing a hydroxyl group at the molecular chain terminal as a dispersant (polymerization degree 10) and methylvinylpolysiloxane containing a hydroxyl group at both molecular terminals (polymerization degree 15, vinyl group content 5 relative to all organic groups) 3 parts by mole) was uniformly mixed in a kneader and heat-treated at 150 ° C. for 2 hours. As a flame retardant aid, 3 parts of triiron tetraoxide KN320 (manufactured by Toda Kogyo Co., Ltd.) and 2 parts of titanium oxide P-25 (manufactured by Nippon Aerosil Co., Ltd.) and crystalline silica crystallite VXS (Co., Ltd.) 40 parts of Tatsumori) and ethanol-modified chloroplatinic acid (platinum content 2 wt%) were added in 0.1 part by two rolls to obtain a base (1).
[0033]
Next, a 10 wt% ethanol solution of diethylenetriamine and triethylenetetramine was prepared, and 0.08 part and 0.1 part were added to each 100 parts of the silicone base (1) prepared above by a roll [Example 1, 2].
[0034]
As a comparative example, 0.1 part of ethanol was added to the base (1) [Comparative Example 1], and 0.08 part of a 10 wt% ethanol solution of benzotriazole was further added [Comparative Example 2].
[0035]
To each of these compositions, 0.5 parts of 2,5-bis (t-butylperoxy) -2,5-dimethylhexane was added, followed by press curing at 170 ° C. for 10 minutes, and then at 200 ° C. × 240. After curing for a minute, a 0.8 mm thick sheet-like molded product was obtained. With respect to this sheet, the number of flame retardant seconds was measured by a method defined in UL94.
[0036]
[Table 1]

[0037]
[Example 3, Comparative Examples 3 and 4]
Dipropylene triamine was made into a 10 wt% solution with ethanol. 0.001 part [Comparative Example 3], 0.097 part [Example 3], and 0.966 part [Comparative Example 4] were added to 100 parts of the base of Example 1, respectively.
[0038]
[Table 2]

[0039]
【The invention's effect】
According to the present invention, a silicone rubber composition that gives a cured product (silicone rubber) having excellent flame retardancy can be obtained by adding and mixing a platinum compound and a specific amine compound to the silicone rubber composition. .

Claims (3)

(A) The following average composition formula (1)
R _a SiO _{(4-a) / 2} (1)
(In the formula, R is the same or different unsubstituted or substituted monovalent hydrocarbon group, and a is a positive number of 1.90 to 2.05.)
100 parts by weight of the organopolysiloxane (b) Reinforcing silica having a specific surface area of at least 50 m ² / g
5 to 100 parts by weight (c) Platinum compound (d) in an amount that results in a platinum amount of 1 to 500 ppm relative to the total amount of components (a) and (b) in terms of platinum amount (d) represented by the following general formula (2) One or more selected from amine compounds

(In the formula, R ¹ is may be the same or different, unsubstituted monovalent hydrocarbon group hydrogen atom or a C1-8, n represents an integer from 2 to 4, m a is 0 or an integer of 1 or more. )
And (e) 0.1 to 10 parts by weight of an organic peroxide in an amount of 1 to 200 moles in terms of the ratio of nitrogen atoms in the molecule to platinum atoms. Flame retardant silicone rubber composition.   The flame retardant silicone rubber composition according to claim 1, wherein the component (d) is diethylenetriamine, triethylenetetramine, tetraethylenepentamine or dipropylenetriamine. The flame retardant silicone rubber composition according to claim 1 or 2, further comprising (f) 0.1 to 20 parts by weight of a compound represented by the following formula with respect to 100 parts by weight of the component (a). object.

(Wherein, R ² may be the same or different, a methyl group, vinyl group or phenyl group, k is an integer of 1 to 50.)