JPH10176110A - Organopolysiloxane composition - Google Patents

Abstract

PROBLEM TO BE SOLVED: To obtain an organopolysiloxane composition which is excellent in storage stability and can give a product improved in surface smoothness by mixing a specified diorganopolysiloxane with an organohyrogenpolysiloxane, a platinum group metal catalyst, an acetylene alcohol reaction inhibitor and an alkynyloxy-containing organopolysiloxane. SOLUTION: This composition comprises a diorganopolysiloxane (A) having at least two alkenyl groups in the molecule and having a viscosity of 10-1,000,000cSt at 25 deg.C, an organohydrogenpolysiloxane (B) having at least two Si-H bonds in the molecule, 0.01-500ppm, based on the total of components A and B, (in terms of the platinum group metal), of a platinum group metal catalyst (C), an acetylene alcohol reaction inhibitor (D) in an amount 1-10 times the weight of component C and having an alkynyl-containing organopolysiloxane (E) used in an amount 0.5-100 times the weight of component D and having at least two monovalent hydrocarbon groups each having a -C<=C- bond bonded to Si through O and a vapor pressure of 2mmHg or below at 120 deg.C.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

The present invention relates to an addition-curable organopolysiloxane composition.

[0002]

2. Description of the Related Art Conventionally, various types of reaction inhibitors have been proposed for use in addition-reaction-curable organopolysiloxane compositions. Among them, acetylene alcohols are among the inhibitors having the best storage stability. It is widely used because it is known and has an excellent reaction suppressing effect. However, since the organopolysiloxane composition containing this type of inhibitor cures from the surface, there is a drawback in that when a thick cured product is obtained, fine wrinkles and irregularities are generated on the surface of the cured product. For this reason, the above-mentioned composition has no internal strain in a coated composition such as a coating agent for a semiconductor device and requires a surface smoothness of a cured product (in particular, an image sensor, an LED, a laser diode, a photodiode) Etc. for optical devices)
May not be suitable for

As a countermeasure, Japanese Patent Publication No. 54-3774 discloses a -C bonded to a silicon atom via an oxygen atom.
A composition using an organopolysiloxane containing an alkynyloxy group having a C-bond has been proposed.
Although this composition has excellent surface smoothness of the cured product, it has poor storage stability as compared with the composition using the acetylene alcohol-based reaction inhibitor, and has a problem in long-term storage.

[0004]

SUMMARY OF THE INVENTION Accordingly, an object of the present invention is to provide an acetylene alcohol-based reaction inhibitor having an excellent reaction suppressing effect and an alkynyloxy group-containing organopolysiloxane having an excellent surface smoothness of a cured product by combining the same. It is an object of the present invention to provide an addition reaction-curable organopolysiloxane composition having excellent storage stability of a product and excellent surface smoothness of a cured product.

[0005]

The above objects can be attained by the following composition of the present invention and a cured product obtained by heating and curing this composition. (A) a diorganopolysiloxane containing at least two alkenyl groups per molecule; (B) an organohydrogenpolysiloxane containing at least two hydrogen atoms bonded to silicon atoms per molecule; (C) A platinum group metal-based catalyst, (D) an acetylene alcohol-based reaction inhibitor, and (E) —C≡C bonded to a silicon atom via an oxygen atom.
-An organopolysiloxane composition containing, as a main component, an alkynyloxy group-containing organopolysiloxane having at least one monovalent hydrocarbon group having a bond in one molecule and having a vapor pressure at 120 ° C of 2 mmHg or less.

[0006]

BEST MODE FOR CARRYING OUT THE INVENTION Hereinafter, the present invention will be described in detail. (A) Alkenyl-Group-Containing Diorganopolysiloxane The alkenyl-group-containing diorganopolysiloxane used in the composition of the present invention contains at least two alkenyl groups in one molecule, and usually has a main chain portion as a base. It is a linear structure composed of repeating diorganosiloxane units, and both ends of the molecular chain are blocked with a triorganosiloxy group, but the molecular structure may contain a branched structure. Or a ring. However, a linear diorganopolysiloxane is preferred from the viewpoint of physical properties such as mechanical strength of the cured product. The alkenyl group may be present only at both ends of the molecular chain, or may be present at both ends of the molecular chain and in the middle of the molecular chain. As a typical example of such an alkenyl group-containing diorganopolysiloxane, for example, the following general formula (1):

[0007]

Embedded image (Wherein, R ¹ is independently an unsubstituted or substituted monovalent hydrocarbon group containing no aliphatic unsaturated bond, X is an alkenyl group, n is an integer of 0 or 1 or more, and m is A diorganopolysiloxane represented by 0 or an integer of 1 or more).

In the general formula (1), examples of the unsubstituted or substituted monovalent hydrocarbon group containing no aliphatic unsaturated bond represented by R ¹ include a methyl group, an ethyl group, a propyl group, an isopropyl group and a butyl group. , Isobutyl, tert-butyl, pentyl, neopentyl, hexyl, heptyl, octyl, nonyl, decyl. Alkyl groups such as dodecyl group; cycloalkyl groups such as cyclopentyl group, cyclohexyl group and cycloheptyl group; aryl groups such as phenyl group, tolyl group, xylyl group, naphthyl group and biphenylyl group; benzyl group, phenylethyl group; An aralkyl group such as a phenylpropyl group or a methylbenzyl group; and a group in which at least a part of a hydrogen atom bonded to a carbon atom of these groups is substituted with a halogen atom such as fluorine, chlorine, or bromine or a cyano group, for example, Chloromethyl group, 2-bromoethyl group, 3-chloropropyl group,
3,3,3-trifluoropropyl group, chlorophenyl group, fluorophenyl group, cyanoethyl group, 3,3
4,4,5,5,6,6,6-nonafluorohexyl group and the like.
0, particularly typical ones having 1 to 6 carbon atoms, preferably methyl, ethyl, propyl, chloromethyl, bromoethyl, 3,3,3-trifluoropropyl, 1 to 3 carbon atoms such as a cyanoethyl group
Or an unsubstituted or substituted alkyl group and an unsubstituted or substituted phenyl group such as a phenyl group, a chlorophenyl group and a fluorophenyl group.

In the general formula (1), examples of the alkenyl group for X include those having 2 to 8 carbon atoms such as vinyl, allyl, propenyl, isopropenyl, butenyl, hexenyl and cyclohexenyl. And lower alkenyl groups such as a vinyl group and an allyl group.

In the general formula (1), n is 0 or an integer of 1 or more, and m is 0 or an integer of 1 or more. And n
And m preferably satisfy 10 ≦ n + m ≦ 10,000, more preferably 50 ≦ n + m ≦ 2,000, and 0 ≦ m / (n + m) ≦ 0.2, particularly 0 ≦ m / (n +
m) is an integer satisfying ≦ 0.05.

The above alkenyl group-containing diorganopolysiloxane has a viscosity at 25 ° C. of 10 to 1,000.
0000 cSt, especially 100-500,000 cSt
Are preferred. The alkenyl group-containing diorganopolysiloxane of the present invention can be used alone or in combination of two or more.

(B) Organohydrogen polysiloxane
The organohydrogenpolysiloxane used in the composition of the present invention contains at least 2, preferably 3 or more hydrogen atoms (ie, SiH groups) bonded to silicon atoms in one molecule. It may be any of a chain-like, branched, cyclic, or three-dimensional network resinous material. Representative examples of such organohydrogenpolysiloxanes include, for example, the following average composition formula (2): H _a R ² _b SiO _{(4-ab) / 2} (wherein R ² is independently aliphatically unsaturated An unsubstituted or substituted monovalent hydrocarbon group containing no bond;
<A <2, 0.8 ≦ b ≦ 2, and 0.8 <a + b ≦ 3
And preferably 0.05 ≦ a ≦ 1, 1.5
≦ b ≦ 2 and 1.8 ≦ a + b ≦ 2.7. )).

In the composition formula (2), as the unsubstituted or substituted monovalent hydrocarbon group containing no aliphatic unsaturated bond of R ² , the same as those exemplified as R ^{1 in the} general formula (1) can be used. And a typical example is one having 1 carbon atom.
A lower alkyl group having 1 to 10 carbon atoms, particularly 1 to 7 carbon atoms, and preferably 1 to 3 carbon atoms such as a methyl group;
A phenyl group; and a 3,3,3-trifluoropropyl group. Examples of such organohydrogenpolysiloxanes include, for example, 1,1,3,3-tetramethyldisiloxane, 1,3,5,7-tetramethyltetracyclosiloxane, 1,3,5,7, Siloxane oligomers such as 8-pentamethylpentacyclosiloxane;
Trimethylsiloxy group-blocked methyl hydrogen polysiloxane with molecular chain at both ends, dimethylsiloxane / methyl hydrogen siloxane copolymer with molecular chain at both ends, methylhydrogenpolysiloxane with silanol group at both ends, molecular chain at both ends Silanol group-blocked dimethylsiloxane / methylhydrogensiloxane copolymer, molecular chain terminal dimethylhydrogensiloxy group-blocked dimethylpolysiloxane, molecular chain terminal dimethylhydrogensiloxy group-blocked methylhydrogenpolysiloxane, molecular chain terminal dimethylhydro Gensiloxy-blocked dimethylsiloxane / methylhydrogensiloxane copolymer, etc .; R ² (H) Si
O _1/2 unit and Si04 _{/ 2} unit, and optionally R ³
SiO _1/2 unit, R ² SiO _2/2 unit, R (H) SiO _2/2
Units, those (H) Si0 _3/2 units or RSi0 may include _3/2 units silicone resin (provided that Shikichu, R represents the same monovalent hydrocarbon radical unsubstituted or substituted exemplified for the aforementioned R ¹ ), And the following formula:

[0014]

Embedded image Are represented.

The organohydrogenpolysiloxane used in the composition of the present invention can be obtained by a known method. For example, the following general formulas: R ² SiHCl ₂ and R ² ₂ SiHCl (wherein R ² is cohydrolysis of at least one chlorosilane selected from the a) same as, or the chlorosilanes with the following general formula: R ² ₃ SiHCl and R ^{₂ 2} SiHCl ² (wherein, R ² is as defined above) And at least one chlorosilane selected from the group consisting of chlorosilanes. Further, the organohydrogenpolysiloxane may be one obtained by equilibrating the polysiloxane obtained by co-hydrolysis in this manner. These organohydrogenpolysiloxanes can be used alone or in combination of two or more.

The amount of the component (B) used is such that the hydrogen atom in the organohydrogenpolysiloxane of the component (B) is usually 0.1 per mole of the alkenyl group in the alkenyl group-containing diorganopolysiloxane of the component (A). The amount is 5 to 4 mol, preferably 1 to 2.5 mol.

(C) Platinum Group Metal Catalyst The platinum group metal catalyst used in the present invention is an addition reaction between the alkenyl group of the component (A) and a hydrogen atom bonded to a silicon atom of the component (B), that is, It is a catalyst for accelerating the hydrosilylation reaction, and examples thereof include well-known catalysts conventionally used for the hydrosilylation reaction. Specific examples thereof include, for example, platinum group metals such as platinum (including platinum black), rhodium, and palladium; and H ₂ PtCl _4.
・ NH ₂ O, H ₂ PtCl ₆・ nH ₂ 0, NaHPtCl ₆
・ NH ₂ O, KHPtCl ₆・ nH ₂ O, Na ₂ PtCl ₆
· NH ₂ O, K ₂ PtCl ₄ · nH ₂ O, PtCl ₄ · nH ₂
Platinum chloride, chloroplatinic acid and chloroplatinate such as O, PtCl ₂ , Na ₂ HPtCl ₄ .nH ₂ O (where n is an integer of 0 to 6, preferably 0 or 6) Alcohol-modified chloroplatinic acid (US Pat. No. 3,220,972)
Complex; chloroplatinic acid and olefin (US Pat. Nos. 3,159,601 and 3,15)
9,662 and 3,775,452); platinum group metals such as platinum black and palladium supported on a carrier such as alumina, silica and carbon; Complexes: Chlorotris (triphenylphosphine) rhodium (Wilkinson's catalyst); complexes of platinum chloride, chloroplatinic acid or chloroplatinate with vinyl group-containing siloxane, particularly vinyl group-containing cyclic siloxane.

The amount of the component (C) used may be a so-called catalytic amount, and is usually 0.1 to 500 ppm, especially 0.1 to 500 ppm in terms of the weight of the platinum group metal relative to the total amount of the components (A) and (B). It may be about 5 to 200 ppm. (D) Acetylene alcohol-based reaction inhibitor The acetylene alcohol used as the reaction inhibitor of the composition of the present invention contains one or more —C≡C— groups and one or more —OH groups in one molecule. And a specific example thereof is 3-methyl-1-butyne-3-
All (trade name Olfin B, manufactured by Nissin Chemical Industry Co., Ltd.), 3
-Methyl-1-pentin-3-ol (trade name Orfin P, manufactured by Nissin Chemical Industry Co., Ltd.), 3,5-dimethyl-1-hexyn-3-ol (trade name Surfinol 61, manufactured by Nissin Chemical Industry Co., Ltd.) ), 1-ethyl-1-cyclohexanol (trade name ethynyl 50 as a toluene solution, manufactured by Nissin Chemical Industry Co., Ltd.) and the like. These can be used alone or in combination of two or more. The amount of the component (D) used is 1 to 100 times the weight of the component (C),
In particular, it may be about 5 to 50 times.

(E) alkynyloxy group-containing organopoi
The alkynyloxy group-containing organopolysiloxane used in the present invention is a monovalent hydrocarbon group having a —C≡C— bond bonded to a silicon atom via an oxygen atom (that is, an alkynyloxy group bonded to a silicon atom). Group) in one molecule and having a vapor pressure at 120 ° C. of 2 mmHg or less. The monovalent hydrocarbon group having an —C≡C— bond (alkynyloxy group) may be bonded to any silicon atom at the terminal of the molecular chain or in the molecular chain. Is preferably bonded to the silicon atom. Also,
In the alkynyloxy group, the -C は C- bond is preferably located at the terminal thereof (that is, has a -C≡CH structure). The monovalent substituent bonded to a silicon atom other than the above-mentioned alkynyloxy group in the organopolysiloxane of the component (E) may be the aforementioned R.
^{The same} unsubstituted or substituted monovalent hydrocarbon group as in 1 is mentioned. Further, this organopolysiloxane has Si in the molecule.
It may contain one or more H groups. Further, the organopolysiloxane of the component (E) may be structurally linear, branched, cyclic or three-dimensional network, and the number of silicon atoms in the molecule is usually 4 to 4. 2
00, preferably about 8 to 120. Specific examples of such component (E) include those represented by the following formula.

[0020]

Embedded image

Embedded image

[0021]

Embedded image

[0022]

Embedded image

Embedded image

The component (E) preferably has excellent compatibility with the components (A) and (B). If the component (E) is inferior in compatibility, it takes a long time to cure the composition, and the composition does not cure uniformly. Moreover, the cured product becomes turbid, hinders transparency, and causes partial curing failure. There is a disadvantage.

The alkynyloxy group-containing organopolysiloxane of the component (E) can be easily produced, for example, by the following method. That is, (CH ₃ ) (H) Si 0
Unit, (CH ₃ ) ₂ (H) SiO _1/2 unit, and HSiO
_After an alcohol having an acetylene bond is added to an organohydrogenpolysiloxane containing at least one of _3/2 units by a dehydrogenation reaction in a suitable solvent in the presence of an alkali alkoxide or an amine, this is added to an appropriate amount. Neutralize with various acids or halosilanes and then distill off the solvent and low boiling compounds. In this case, the mixing ratio of the organohydrogenpolysiloxane and the alcohol having an acetylene bond is such that the number of hydroxyl groups in the alcohol is at least one per hydrogen atom bonded to a silicon atom in the organohydrogenpolysiloxane. Ratio. In addition, the solvent and the low-boiling compound (particularly, having a boiling point of 2
When the compound (50 ° C. or lower) is distilled off, it is desirable to remove the compound as sufficiently as possible. If the distillation is insufficient, there is a disadvantage that the obtained compound is easily wrinkled. Examples of the alcohol having an acetylene bond that can be used here include the following compounds.

[0025]

Embedded image The alkynyloxy group-containing organopolysiloxane obtained by the above method can be used alone or in combination of two or more.

The amount of the alkynyloxy group-containing organopolysiloxane of the component (E) may be 0.5 to 100 times, preferably 1 to 50 times the weight of the component (D).

Other Additives Various known additives can be added to the composition of the present invention, if necessary. To reinforce the strength of the cured product obtained, for example, Si0 _{2 units, (CH 2 = CH) R} '2
SiO _0.5 units, R _'3 SiO _0.5 units (wherein, R' is a monovalent hydrocarbon group shown free of aliphatic unsaturated bonds) organopolysiloxane composed of resin structure (JP-B 38
-26771 and 45-9476). However, when such a vinyl group-containing organopolysiloxane resin is added, as specified in the component (B), the amount used is based on the amount of silicon based on one vinyl group bonded to silicon atoms in the entire composition. It is necessary to make the amount such that 0.5 to 4 hydrogen atoms are bonded to the atoms. Further, in order to improve the adhesiveness of the composition, an epoxy group-containing polysiloxane compound or an ester siloxane compound, that is, an organopolysiloxane in which all monovalent substituents bonded to a silicon atom other than a hydrogen atom and a hydroxyl group are alkoxy groups. Siloxane can be added.

Further, the composition of the present invention may have a reduced thermal shrinkage during curing, a reduced thermal expansion coefficient of an elastic body obtained by curing, a thermal stability, a weather resistance, a chemical resistance, a flame retardancy or a mechanical resistance. In order to improve the mechanical strength or lower the gas permeability,
Fillers may be added. Examples of the filler include metal oxides such as fumed silica, quartz powder, glass fiber, carbon black, alumina, iron oxide, and titanium oxide; and metal carbonates such as calcium carbonate and magnesium carbonate.

In addition, a suitable pigment may be used in the composition of the present invention.
Dyes or antioxidants can be added.

When the composition of the present invention is put to practical use, the composition can be used by dissolving or dispersing it in a desired concentration in an appropriate organic solvent such as toluene or quinylene depending on the use and purpose.

[0031]

The present invention will be described below in more detail with reference to Examples and Comparative Examples. Example 1 Dimethylpolysiloxane in which both ends of a molecular chain are blocked with a dimethylvinylsiloxy group (viscosity at 25 ° C .: 2,000
cSt) 100 parts by weight, 0.8 mol / l of SiH bond
3.0 g of methylhydrogenpolysiloxane containing 0.1 g of 0.1 g of a solution of octyl alcohol-modified chloroplatinic acid (platinum content: 0.5 wt%), 3-methyl-1-butyl-3-ol (Product name Olfille B)
0.1 parts by weight, and the following formula:

[0032]

Embedded image (In the formula, Me represents a methyl group, and n = 10.3, m
= 7.7) was sufficiently mixed with 0.5 part by weight of an alkynyloxy group-containing organopolysiloxane to prepare an organopolysiloxane composition. Table 1 shows the results of testing the storage stability and the cured state of this composition.

Storage stability The samples were placed in a 60 ° C. heater at 24, 48, 96, 144,
The time-dependent changes in viscosity of each of 192 and 240 when left to stand were measured by a BM-type rotational viscometer (manufactured by Tokyo Keiki). The measured viscosity values in Table 1 are based on Poise. Cured state A sample molded to a thickness of 2 mm was cured at 150 ° C. for 1 hour, and the surface condition of the cured product was visually observed. The hardness of the rubber was measured using a spring type hardness tester A type specified in JIS K6301. Measure using

Example 2 The amount of 3-methyl-1-butyl-3-ol was 0.0
An organopolysiloxane composition was prepared in the same manner as in Example 1 except that the amount was 25 parts by weight, and the storage stability and the cured state were similarly tested. Table 1 shows the results. Example 3 The amount of 3 -methyl-1-butyl-3-ol was 0.0
An organopolysiloxane composition was prepared in the same manner as in Example 1 except that the amount was 75 parts by weight and the amount of the alkynyloxy group-containing organopolysiloxane was 0.3 part by weight. Was tested. Table 1 shows the results. Example 4 In the same manner as in Example 1, except that 0.1 part by weight of 3-methyl-1-pent-3-ol was used instead of 0.1 part by weight of 3-methyl-1-butyl-3-ol. An organopolysiloxane composition was prepared, and the storage stability and the cured state were similarly observed. Table 1 shows the results. Example 5 Example 1 was repeated except that 0.1 part by weight of 3-methyl-1-butyl-3-ol was replaced by 0.2 part by weight of a 50% by weight solution of 1-ethyl-1-cyclohexanol in toluene. Organopolysiloxane compositions were prepared in the same manner and similarly tested for storage stability and cured state. Table 1 shows the results.
Shown in

Comparative Example 1 An organopolysiloxane composition was prepared in the same manner as in Example 1 except that the alkynyloxy group-containing organopolysiloxane was not used, and the storage stability and the cured state were similarly tested. Table 1 shows the results. Comparative Example 2 An organopolysiloxane composition was prepared in the same manner as in Example 1 except that 3-methyl-1-butyl-3-ol was not used, and the storage stability and the cured state were similarly tested. Table 1 shows the results. Comparative Example 3 The amount of 3 -methyl-1-butyl-3-ol was 0.0
An organopolysiloxane composition was prepared in the same manner as in Example 1 except that the content was 25 parts by weight and the alkynyloxy group-containing organopolysiloxane was not used, and the storage stability and the cured state were similarly tested. Table 1 shows the results.

[0036]

[Table 1]

[0037]

The addition-reaction-curable organopolysiloxane composition of the present invention has excellent storage stability and also has excellent surface smoothness of the cured film, and especially a coating agent for a semiconductor device requiring surface smoothness. Useful as

Claims (2)

[Claims] 1. A diorganopolysiloxane containing at least two alkenyl groups in one molecule, and B. an organohydrogenpolysiloxane containing at least two hydrogen atoms bonded to silicon atoms in one molecule. Siloxane, (C) a platinum group metal-based catalyst, (D) an acetylene alcohol-based reaction inhibitor, and (E) —C≡C bonded to a silicon atom via an oxygen atom.
-An organopolysiloxane composition containing, as a main component, an alkynyloxy group-containing organopolysiloxane having at least one monovalent hydrocarbon group having a bond in one molecule and having a vapor pressure at 120 ° C of 2 mmHg or less. 2. A cured product obtained by heating and curing the organopolysiloxane composition according to claim 1.