JP3036385B2 - Curable composition - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a curable composition which is easily cured by being left or heated at room temperature, is excellent in solvent resistance, chemical resistance and heat resistance and gives a cured product having particularly large elongation. .

[0002]

2. Description of the Related Art Conventionally, fluorine-containing elastomer compositions have been used in various fields.

However, a cured product obtained from a conventionally marketed fluorine-containing elastomer composition may not have sufficient solvent resistance and chemical resistance in some cases.
A cured product having excellent chemical resistance is desired. Further, depending on the application, it is particularly desired that the cured rubber has a large elongation.

The present invention has been made in order to meet the above-mentioned demands, and mainly comprises a fluorinated amide compound and a fluorinated organohydrogensiloxane which are excellent in solvent resistance and chemical resistance and give a cured product having large elongation. It is intended to provide a curable composition as a component.

[0005]

Means for Solving the Problems and Actions The present inventors have conducted intensive studies to achieve the above object, and as a result, have found that a fluorine-containing amide compound represented by the following general formula (1) is represented by the following general formula (4). By blending the indicated fluorine-containing organohydrogensiloxane as a crosslinking agent and a chain extender, and adding a platinum group compound as a catalyst, it is easily cured at room temperature and has excellent solvent resistance, chemical resistance and heat resistance. In addition, the inventors have found that a curable composition giving a cured product having a large elongation can be obtained, and the present invention has been accomplished.

Accordingly, the present invention provides (A) a fluorine-containing amide compound represented by the following general formula (1), (B) a fluorine-containing organohydrogensiloxane having a hydrosilyl group represented by the following general formula (4), (C) A) a composition containing a catalytic amount of a platinum group compound, wherein the amount of the component (B) is such that the hydrosilyl group is 0.5 to 5 mol per 1 mol of the aliphatic unsaturated group in the composition; Curable composition characterized in that the amount is curable.

[0007]

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[0008]

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Hereinafter, the present invention will be described in more detail. The curable composition of the present invention comprises a fluorine-containing amide compound represented by the above formula (1) and a crosslinking agent or a chain extender represented by the above formula (4). It contains a fluorine-containing organohydrogensiloxane and a platinum group compound as a catalyst.

The first essential component [component (A)] of the first curable composition of the present invention is a fluorinated amide compound, and the fluorinated amide compound of component (A) is represented by the following general formula (1). As shown, it has at least two aliphatic unsaturated groups in the molecule.

[0011]

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Here, R ¹ in the above formula (1) is:
2 to 10 carbon atoms having an aliphatic unsaturated bond, particularly 2 to 8 carbon atoms
Preferred are monovalent hydrocarbon groups such as vinyl, allyl, propenyl, isopropenyl, butenyl,
Examples thereof include an alkenyl group such as a hexenyl group, a cycloalkenyl group such as a cyclohexyl group, and an aryl group substituted with an alkenyl group such as a styryl group.

Next, as R ² , a hydrogen atom or a carbon atom having 1 to 10 carbon atoms, especially a carbon atom having 1 to 10 carbon atoms, excluding an aliphatic unsaturated bond,
8 substituted or unsubstituted monovalent hydrocarbon groups are preferred, for example, methyl, ethyl, propyl, isopropyl, butyl, isobutyl, tert-butyl, pentyl, neopentyl, hexyl, Heptyl group,
Alkyl groups such as octyl group, nonyl group and decyl group; cycloalkyl groups such as cyclopentyl group, cyclohexyl group and cycloheptyl group; alkenyl groups such as vinyl group, allyl group, propenyl group, isopropenyl group, butenyl group and hexenyl group. , An aryl group such as a phenyl group, a tolyl group, a xylyl group, or a naphthyl group, an aralkyl group such as a benzyl group or a phenylethyl group, or a chloromethyl group in which part or all of the hydrogen atoms of these groups have been substituted with halogen atoms or the like. Chloropropyl group, trifluoropropyl group and the like.

In the above formula (1), Q ¹ is a group represented by the following formula (2) or (3).

[0015]

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R ² in the above formula (2) is the same as described above, and R ³ is not particularly limited as long as it is a substituted or unsubstituted divalent hydrocarbon group. ~
Preferred are hydrocarbon groups of 10, specifically methylene group, ethylene group, propylene group, methylethylene group, butylene group, alkylene group such as hexamethylene group, cycloalkylene group such as cyclohexylene group, phenylene group,
Examples include an arylene group such as a tolylene group and a xylylene group, a group in which part or all of the hydrogen atoms of these groups are substituted with a halogen atom, or a combination of these substituted or unsubstituted alkylene groups and arylene groups. .

R ³ may contain one or more of oxygen, nitrogen and silicon atoms in the course of the bond.

In this case, the oxygen atom is interposed as -O-, and the nitrogen atom is interposed as -NR'- (R 'is a hydrogen atom or an alkyl or aryl group having 1 to 8, especially 1 to 6 carbon atoms). And a silicon atom can be interposed as a group containing a linear or cyclic organosiloxane or an organosilylene group as shown below.

[0019]

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Examples of such groups include the following groups.

[0021]

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Further, as R ⁴ and R ⁵ in the above formula (3), a substituted or unsubstituted divalent hydrocarbon group having 1 to 10, especially 2 to 6, carbon atoms is preferable. Methylene group,
An alkylene group such as an ethylene group, a propylene group, a methylethylene group, a butylene group, and a hexamethylene group; a cycloalkylene group such as a cyclohexylene group; or a group in which some or all of the hydrogen atoms of these groups have been substituted with halogen atoms or the like. And the like.

Specific examples of Q ¹ in the formula (1) represented by the above formula (2) or (3) include the following groups. In the following chemical formula, Me is a methyl group, P
h represents a phenyl group.

[0024]

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In the formula (1), Rf ¹ is a divalent perfluoroalkylene group or a divalent perfluoropolyether group, and particularly, as the divalent perfluoroalkylene group, is -C _m F _2m- = 1 to 10, preferably 2 to 6), and the divalent perfluoropolyether group is preferably a group represented by the following formula.

[0026]

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Specific examples of Rf ¹ include the following.

[0028]

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In the above formula (1), a is an integer of 0 or more. Therefore, the fluorine-containing amide compound of the formula (1) contains a divalent perfluoroalkylene group or a divalent perfluoropolyether group in one molecule. Wherein a is preferably an integer of 0 to 10, especially 0,
1, 2, 3, 4, 5, and 6 are exemplified.

In the present invention, as the fluorine-containing amide compound as the component (A), a low-viscosity polymer having a viscosity (25 ° C., the same applies hereinafter) of several tens cs to a solid raw rubber-like polymer can be used. From the viewpoint of ease of handling, for example, a raw rubber-like polymer is used for hot vulcanized rubber, and a viscosity of 100 to 100000 is used for liquid rubber.
Polymers of the order of cs are preferably used. If the viscosity is too low, the resulting cured product will have a low elongation as an elastomer, and may not have balanced physical properties.

The fluorine-containing amide compound of the above formula (1) is
It can be obtained by the following method. That is, the fluorine-containing amide compound in which a is 0 in the formula (1) is
For example, it is synthesized by reacting a compound having an acid fluoride group at both terminals represented by the following general formula (i) with a secondary amine compound represented by the following general formula (ii) in the presence of an acid acceptor such as trimethylamine. can do.

[0032]

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Further, the fluorine-containing amide compound in which a is an integer of 1 or more in the above formula (1) is, for example, a compound having an acid fluoride group at both terminals shown in the above formula (i) and the following general formula (iii) ^{H-Q 1 -H ...... (iii} ) (Q 1 in. which indicates the same meaning as above) is reacted in the presence of an acid acceptor with a compound represented by represented by further above formula (ii) two It can be synthesized by reacting a secondary amine compound.

In this case, the ratio of the charged amounts of the compound having an acid fluoride group at both terminals of the formula (i) and the secondary amine compound of the formula (ii) is not particularly limited, but is calculated in terms of mol. The ratio (b) / (a) between the charged amount (a) of the compound of formula (i) and the charged amount (b) of the compound of formula (ii) is 2 to 1
It is preferably 0, especially 2 to 5 mol / mol.

The charged amount (a) of the compound of the formula (i) and the charged amount (c) of the compound of the formula (iii) are not particularly limited as long as (a) is not smaller than (c) in terms of mole. It is not limited. The repeating unit a in the formula (1) is
By adjusting (a) / (c), an appropriate value according to the purpose can be obtained. By increasing (a) / (c), a polymer having a relatively small molecular weight can be synthesized,
When the value of (a) / (c) approaches 1, a polymer having a large molecular weight can be synthesized.

The conditions for the above reaction are not particularly limited.
20 to 100 ° C for 1 to 8 hours, preferably 20 to 50 ° C
For 2 to 4 hours.

In the fluorinated amide compound of the formula (1), Q ^{1 in} which a silicon atom is interposed is a compound of the formula (ii) wherein R ¹ is an allyl group or the like. HR ² NCH ₂ CH =
Using a secondary amine compound having an aliphatic unsaturated group represented by CH ₂ or the like, the above-mentioned reaction yields, for example, the following general formula (i
It can be synthesized by synthesizing a compound having allyl groups at both ends represented by v) and reacting the compound with, for example, a compound represented by the following general formula (V) in the presence of an addition reaction catalyst.

[0038]

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[0039]

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In this reaction, the ratio of the charged amount of the compound of the formula (V) to the compound of the formula (V) and the compound having the allyl group at both terminals represented by the above formula (iv) is calculated as follows: (D) must be greater than the charge (e) of the compound of formula (V), but the ratio (d) / (e) is at most 2
It is. That is, 1 <(d) / (e) ≦ 2.

By increasing (d) / (e), a polymer having a relatively small molecular weight can be synthesized.
When the value of (d) / (e) approaches 1, a polymer having a large molecular weight can be synthesized.

[0042] In this case, the catalyst may be selected from the periodic table VI.
Group II elements or compounds thereof, such as chloroplatinic acid, alcohol-modified chloroplatinic acid (see U.S. Pat. No. 3,220,972), complexes of chloroplatinic acid with olefins (U.S. Pat.
No. 159601, No. 3159662, No. 3775
No. 452), platinum black or palladium is alumina,
Silica, carbon-supported carrier, rhodium-olefin complex, chlorotris (triphenylphosphine) rhodium (Wilkinson's catalyst), etc.
The addition amount can be a catalyst amount. The above complex is preferably used after being dissolved in an alcohol, ketone, ether or hydrocarbon solvent.

The conditions for the above reaction are 50 to 150.
C., preferably at 80 to 120.degree. C. for 2 to 4 hours.

Next, the second essential component [component (B)] of the first curable composition of the present invention is a fluorinated organohydrogensiloxane, which is used as a crosslinking agent and a chain extender for the fluorinated amide compound. It works. The fluorine-containing organohydrogensiloxane of the component (B) is represented by the following general formula (4).

[0045]

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Here, Rf ² is a divalent perfluoroalkylene group or a divalent perfluoropolyether group, and examples thereof include the same groups as Rf ¹ described above. R ² and R ³ have the same meaning as described above. Further, T represents a group represented by the following general formula (5).

[0047]

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In the above formula, R ⁶ is a substituted or unsubstituted monovalent hydrocarbon group and preferably has 1 to 10 carbon atoms, particularly 1 to 8 carbon atoms, and is the same as R ² in the formula (1). And a group other than an alkenyl group is preferable. Here, b is an integer of 2 to 4.

The following are examples of the fluorine-containing organohydrogensiloxane of the formula (4). One of these may be used alone, or two or more thereof may be used in combination.

[0050]

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The compounding amount of the above component (B) is based on 1 mole of the aliphatic unsaturated group such as vinyl group, allyl group and cycloalkenyl group contained in component (A). The amount of the hydrosilyl group, i.e., Si-H group, is preferably 0.5 to 5 mol, more preferably 1 to 2 mol. If the amount is less than 0.5 mol, the degree of crosslinking is insufficient, and if the amount is 5 mol or more, the chain length is prioritized and curing is insufficient, foaming, heat resistance, compression set properties and the like may be deteriorated. . The amount of the component (B) relative to the component (A) is usually in the range of 0.1 to 50 parts by weight based on 100 parts by weight of the component (A).

Further, the platinum group compound, which is the third essential component [component (C)] of the first curable composition of the present invention, undergoes an addition reaction between the above-mentioned fluorine-containing amide compound and the above-mentioned fluorine-containing organohydrogensiloxane ( Hydrosilylation) and acts as a curing accelerator. This platinum group compound is generally a compound of a noble metal and is expensive, so a platinum compound which is relatively easily available is often used.

Examples of the platinum compound include chloroplatinic acid or a complex of chloroplatinic acid with an olefin such as ethylene, a complex of alcohol or vinyl siloxane, platinum / silica, alumina or carbon. However, the present invention is not limited to this. Examples of platinum group compounds other than platinum compounds include rhodium, ruthenium, iridium,
Palladium compounds are also known, for example, RhCl
(PPh ₃ ) ₃ , RhCl (CO) (PPh ₃ ) ₂ , R
hCl (C ₂ H ₄ ) ₂ , Ru ₃ (CO) ₁₂ , IrCl
(CO) (PPh ₃ ) ₂ , Pd (PPh ₃ ) _{4 and the} like.

When these catalysts are used, when they are fixed catalysts, they can be used in solid form, but in order to obtain a more uniform cured product, chloroplatinic acid or a complex is appropriately dissolved in a solvent. It is preferable to use the compound obtained by compatibilizing the fluorinated amide compound as the first component.

The amount of the catalyst used is not particularly limited, and a desired curing rate can be obtained with the amount of the catalyst. However, in order to obtain an economical viewpoint or a good cured product, the curable composition must be used. The amount is preferably in the range of about 1 to 1000 ppm (in terms of platinum group), more preferably about 10 to 500 ppm (as described above), based on the total amount of the substance.

Various additives can be added to the curable composition of the present invention, if necessary, to enhance its practicality. Specifically, it contains CH ₂ ＣＨCH (R) SiO units (where R is a substituted or unsubstituted monovalent hydrocarbon group) added for the purpose of controlling the curing rate of the curable composition. Polysiloxane (Japanese Patent Publication No. 48-10947)
And acetylene compounds (US Patent No. 344).
No. 5420 and Japanese Patent Publication No. 54-3774), and an ionic compound of a heavy metal (US Pat. No. 353,264).
No. 9).

When these additives are added,
The blending amount of the fluorine-containing organohydrogensiloxane is determined in consideration of the blending amounts of these additives in addition to the component (A), and as described above, the vinyl group, allyl group, cycloalkenyl group in the total composition. It is necessary that 0.5 to 5 mol of Si—H groups be present per 1 mol of the aliphatic unsaturated group such as described above.

Further, the curable composition of the present invention has a reduced heat shrinkage during curing, a reduced coefficient of thermal expansion of an elastic material obtained by curing, a thermal stability, a weather resistance, a chemical resistance, and a flame retardant. A filler may be added for the purpose of improving the properties or mechanical strength or lowering the gas permeability, such as fumed silica, quartz powder, glass fiber, carbon, iron oxide, titanium oxide, and cerium oxide. Oxides, metal carbonates such as calcium carbonate, magnesium carbonate and the like can be mentioned, and if necessary, suitable pigments, dyes or antioxidants can be added.

The method for producing the curable composition of the present invention is not particularly limited, and it can be produced by kneading the above components. The produced curable composition can be cured at room temperature depending on the functional group of the fluorine-containing amide compound as the first essential component and the type of the catalyst as the third essential component.
It is preferable to cure at 0 ° C. for several minutes to several hours.

In using the curable composition of the present invention, the composition is dissolved in a suitable fluorine-based solvent, for example, meta-xylene hexafluoride, florinate, or the like at a desired concentration depending on the use and purpose. May be used.

[0061]

The curable composition of the present invention can be used for various uses. That is, the cured product obtained from the curable composition of the present invention has a very large elongation and a high fluorine content, so that it has excellent solvent resistance and chemical resistance, and has a low surface energy, so that it is released. It is excellent in water resistance and water repellency, and can be effectively used as a rubber material for automobiles, a tent film material, a sealant, a molded part, an extruded part, a coating material, a release agent, etc., which require oil resistance.

[0062]

EXAMPLES Hereinafter, the present invention will be described specifically with reference to Examples and Comparative Examples, but the present invention is not limited to the following Examples. In the following, Me indicates a methyl group and Ph indicates a phenyl group.

[Example 1, Comparative Examples 1 and 2] The following formula (A)
(Viscosity 3300 cs, average molecular weight 1
6000, 0.0124 mol / 100 g of vinyl group) 1
Specific surface area 2 treated with trimethylsiloxy group
After adding 10 g of fumed silica of 00 m ² / g, mixing and heat-treating, the mixture was mixed on a three-roll mill, and the crosslinking agents represented by the following formulas (B) to (D) were further added in the amounts shown in Table 1. And chloroplatinic acid is mixed with CH ₂ ＣＨCHSiMe ₂ OSiM
0.2 g of a toluene solution of a catalyst modified with e ₂ CH = CH ₂ (platinum concentration: 1.0% by weight) was added and mixed, and the composition I
~ III were prepared.

[0064]

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Each of the compositions I to III was defoamed under reduced pressure, placed in a rectangular frame having a thickness of 2 mm, evacuated again, and press-cured at 120 kg / cm ² and 150 ° C. for 20 minutes. A test piece is cut out from the cured sample, and JIS
When the physical properties were measured in accordance with K6301, the results shown in Table 1 were obtained.

[0066]

[Table 1]

Next, heat resistance, solvent swellability, chemical resistance, and low-temperature characteristics were measured using the test piece of the composition I. The results are shown in Tables 2, 3, 4 and 5.

[0068]

[Table 2]

[0069]

[Table 3]

[0070]

[Table 4]

[0071]

[Table 5]

Example 2 Crosslinking agent 1 used in Example 1
Is replaced with 6.0% of a crosslinking agent IV represented by the following formula (E).
Composition IV as in Example 1 except that parts by weight were used
It was created. A cured sheet was prepared in the same manner as in Example 1.

[0073]

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Next, when the rubber properties of this sheet were measured in accordance with JIS K6301, the following values were obtained.

Hardness (JIS-A) 44 Elongation (%) 530 Tensile strength (kgf / cm ² ) 29

Example 3, Comparative Example 3 Instead of the polymer of the formula (A) in Example 1, a polymer represented by the following formula (F) (viscosity 28600 cs, average molecular weight 28000,
Using 100 parts by weight of the vinyl group (0.007 mol / 100 g), 9.0 parts by weight of the crosslinking agent I of Example 1 or the crosslinking agent
Compositions V and VI were prepared in the same manner as in Example 1 except that 1.62 parts by weight of III was used, and a cured sheet was prepared.

[0077]

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A test piece of the obtained cured sheet was cut out,
When the physical properties were measured in the same manner as above, the results shown in Table 6 were obtained.

[0079]

[Table 6]

Example 4, Comparative Example 4 Instead of the polymer of the formula (A) in Example 1, a polymer represented by the following formula (G) (viscosity 13100 cs, average molecular weight 19200,
Using 100 parts by weight of the vinyl group (0.010 mol / 100 g), 4.8 parts by weight of the crosslinking agent I of Example 1 or the crosslinking agent
Compositions VII and VIII were prepared in the same manner as in Example 1 except that 0.95 part by weight of III was used, and a cured sheet was prepared.

[0081]

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A test piece of the obtained cured sheet was cut out,
When the physical properties were measured in the same manner as above, the results shown in Table 7 were obtained.

[0083]

[Table 7]

Reference Example 1 189.2 g (viscosity: 430 cs; 25 ° C.) of a compound having an acid fluoride group at both terminals represented by the following formula (H) was equipped with a stirring bar, a thermometer, a Dim funnel, and a dropping funnel. A 300 ml four-necked flask was charged, and a mixture of 9.6 g of allylaniline and 6.1 g of triethylamine was added to the mixture from a dropping funnel while stirring.
It was added dropwise at ° C.

[0085]

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After the dropwise addition, the reaction was carried out at 60 ° C. for 2 hours, and the reaction mixture was filtered under pressure to obtain a filtrate obtained at 120 ° C./3 m
Stripping under reduced pressure at mHg gave 190.1 g of a pale yellow transparent liquid compound.

The obtained compound had a viscosity of 1192 cs (2
5 ° C.), specific gravity 1.841 (25 ° C.), refractive index 1.320
8 (25 ° C.). As a result of IR measurement of this compound, the following absorptions were recognized.

1100-1300 cm ⁻¹ ν _CF 1695 cm ⁻¹ ν _{C = O} 1600, 1500 cm ⁻¹ arom. When the amount of allyl group of this compound was measured, it was found to be 0.1%.
It was 31 mol / 100 g, and it was confirmed that the obtained compound was a polymer of an organic fluorine compound represented by the following structural formula (I).

[0089]

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[Reference Example 2] 76.9 g of a compound having an acid fluoride group at both terminals represented by the above formula (H) (viscosity:
430 cs; 25 ° C.) with a stirring rod, thermometer, Dimroth,
A 200 ml four-necked flask equipped with a dropping funnel was charged, and a mixture of 1.14 g of 2,5-dimethylpiperazine and 2.9 g of triethylamine was added dropwise at 20 ° C from the dropping funnel with stirring. After the dropwise addition, the reaction was carried out at 60 ° C. for 2 hours, after which 0.36 g of methylallylamine was added. Further, the reaction and post-treatment were carried out in the same manner as in Reference Example 1 to obtain 72.9 g of a pale yellow transparent liquid compound.

The obtained compound had a viscosity of 25200 cs
(25 ° C.). As a result of IR measurement of this compound,
The following absorptions were observed.

1100-1300 cm ⁻¹ ν _CF 1690 cm ⁻¹ ν _{C CO When the} amount of allyl groups of this compound was determined, it was found that
005 mol / 100 g, and it was confirmed that the obtained compound was a polymer of an organic fluorine compound represented by the following structural formula (J).

[0093]

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Reference Example 3 A compound 10 having an allyl group at both terminals represented by the following formula (K) was prepared in the same apparatus as in Reference Example 2.
0.0 g (viscosity: 1192 cs; 25 ° C.) and 50.0 g of meta-xylene hexafluoride were charged, heated to 90 ° C. with stirring, and 0.1 g of a 2% solution of chloroplatinic acid in isopropyl alcohol was added. Thereafter, 3.66 g of cyclotetrasiloxane represented by the following formula (L) was added dropwise from a dropping funnel, and a reaction was performed.

[0095]

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After the dropwise addition, the disappearance of cyclotetrasiloxane was confirmed by gas chromatography while aging. After cooling to room temperature, 1.5 g of activated carbon was added and the mixture was stirred for 2 hours. This was subjected to the same post-treatment as in Reference Example 1, whereby 99.2 g of a transparent liquid compound was obtained.

The obtained compound had a viscosity of 30700 cs
(25 ° C.). As a result of IR measurement of this compound,
The following absorptions were observed.

1100 to 1300 cm ⁻¹ ν _CF 1690 cm ⁻¹ ν _{C = O} 1600, 1500 cm ⁻¹ arom. Further, when the amount of allyl group of this compound was quantified, it was found to be 0.1%.
007 mol / 100 g, and it was confirmed that the obtained compound was a polymer of an organic fluorine compound represented by the following structural formula (M).

[0099]

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──────────────────────────────────────────────────続 き Continuing on the front page (72) Inventor Nobuyuki Kobayashi 1-10, Hitomi, Matsuida-cho, Usui-gun, Gunma Prefecture Shin-Etsu Chemical Co., Ltd. Silicone Electronics Materials Research Laboratory (56) References JP-A-6-256635 ( JP, A) JP-A-6-271765 (JP, A) JP-A-6-256500 (JP, A) (58) Fields investigated (Int. Cl. ⁷ , DB name) C08L 1/00-101/14 C08G 65/00-65/48 C08G 77/00-77/62 C08G 81/00-81/02

Claims (1)

(57) [Claims] (A) a fluorine-containing amide compound represented by the following general formula (1): (B) The following general formula (4) A composition comprising a hydrosilyl group-containing fluorinated organohydrogenpolysiloxane having the formula (C) and a catalytic amount of a platinum group compound, wherein the component (B) is contained in an amount of an aliphatic unsaturated group in the composition. The hydrosilyl group is contained in an amount of 0.1 to 1 mol.
A curable composition characterized in that the amount is 5 to 5 mol.