JPH05209088A - Curable composition - Google Patents

Abstract

PURPOSE:To obtain the subject composition improved in surface tackfreeness after curing by mixing a compound containing alkenyl group(s), a compound containing hydrosilyl groups, a hydrosilylation catalyst and a surface tack modifier. CONSTITUTION:100 pts.wt. total of a compound (A) which consists of a main chain comprising a polyether with a number-average molecular weight of 500 to 50,000 and has at least one alkenyl group in the molecule and a compound (B) which has at least two hydrosilyl groups in the molecule and a molecular weight of 500 to 50,000 is mixed with a hydrosilylation catalyst (C) in an amount of 10<-1> to 10<-8>mol per mol of the alkenyl group of component A and 0.1-50 pts.wt. surface tack modifier (D).

Description

Detailed Description of the Invention

[0001]

FIELD OF THE INVENTION The present invention relates to a curable composition. More specifically, (A) a compound having at least one alkenyl group in the molecule, (B) a compound having at least two hydrosilyl groups in the molecule, (C) a hydrosilylation catalyst, and (D) surface tack modification. The present invention relates to a curable composition containing an agent as a main component and having an improved surface tack after curing.

[0002]

2. Description of the Related Art Conventionally, curable compositions containing the above-mentioned components (A) to (C) as main components have fast curing properties at high temperatures, and are therefore considered to be expected to be used in various applications. ing. However, in many cases, this composition had a major drawback that tackiness (surface tack) remained on the surface after curing. In this way, if surface tack remains, when used for applications such as sealants, sealing materials, paints, heat-resistant masking tapes for printed circuit boards, etc. It is not preferred.

[0003]

SUMMARY OF THE INVENTION In view of the above situation, the present invention provides a curable composition in which surface tack does not remain after curing.

[0004]

That is, the present invention relates to a curable composition containing the following four components (A) to (D) as main components. (A) a compound having at least one alkenyl group in the molecule, (B) a compound having at least two hydrosilyl groups in the molecule, (C) a hydrosilylation catalyst, (D) a surface tack modifier.

There are no particular restrictions on the compound having at least one alkenyl group in the molecule, which is the component (A) of the present invention, and various compounds from low molecular weight compounds to organic polymers can be used. The alkenyl group is not particularly limited, but is of the formula (I)

[0006]

[Chemical 1]

An alkenyl group represented by the formula (wherein R ¹ is hydrogen or a methyl group) is preferable. To specifically describe the component (A), first, the formula (II)

[0008]

[Chemical 2]

(R ¹ is hydrogen or methyl, R ² is 1 to
Twenty divalent hydrocarbon groups may contain one or more ether bonds. R ³ is an aliphatic or aromatic organic group, and a is a positive integer. The compound which has the ether bond represented by these is mentioned. In formula (II), R ² has 1 to 20 carbon atoms.
The above divalent hydrocarbon group is represented by R ² , but R ² may contain one or more ether bonds. In particular,

[0010]

[Chemical 3]

And the like. Due to ease of synthesis
CH ₂ - is preferred. In formula (II), R ³ is an aromatic or aliphatic organic group. Specifically,

[0012]

[Chemical 4]

[0013]

[Chemical 5]

And the like. Of these, the following are preferred.

[0015]

[Chemical 6]

R ³ may be an organic polymer, and various kinds can be used. First, as the polyether polymer, for example, polyoxyethylene, polyoxypropylene, polyoxytetramethylene, polyoxyethylene-polyoxypropylene copolymer and the like are preferably used. Other polymers having a main chain skeleton include polyester polymers obtained by condensation of a dibasic acid such as adipic acid and glycol, or ring-opening polymerization of lactones,
Ethylene-propylene copolymer, polyisobutylene,
Copolymers of isobutylene and isoprene, etc., polychloroprene, polyisoprene, copolymers of isoprene and butadiene, acrylonitrile, styrene, etc., polybutadiene, copolymers of butadiene and styrene, acrylonitrile, etc., polyisoprene, polybutadiene, isoprene Alternatively, a polyolefin-based polymer obtained by hydrogenating a copolymer of butadiene and acrylonitrile, styrene, etc., polyacrylic acid ester obtained by radical polymerization of monomers such as ethyl acrylate, butyl acrylate, ethyl acrylate, butyl acrylate, etc. Polymerization of acrylic acid ester-based copolymers of vinyl acetate, acrylonitrile, methyl methacrylate, styrene, etc., and vinyl monomers in the organic polymer The resulting graft polymer, polysulfide polymer, nylon 6 by ring-opening polymerization of ε-caprolactam, nylon 66 by condensation polymerization of hexamethylenediamine and adipic acid, nylon 610 by condensation polymerization of hexamethylenediamine and sebacic acid, ε Polyamides such as nylon 11 by condensation polymerization of aminoundecanoic acid, nylon 12 by ring-opening polymerization of ε-aminolaurolactam, and polyamide polymers such as copolymerized nylon having two or more components among the above nylons, for example, bisphenol A Examples include polycarbonate-based polymers and diallyl phthalate-based polymers produced by condensation polymerization from carbonyl chloride. Then, the general formula (III)

[0017]

[Chemical 7]

(R ¹ is hydrogen or a methyl group, R ² has 1 carbon atom
It is a divalent hydrocarbon group of -20 and may contain one or more ether bonds. R ⁴ is an aliphatic or aromatic organic group, and a is a positive integer. The compound which has an ester bond represented by these is mentioned. In formula (III), R ² is the same as R ² in formula (II). R ⁴ is an aromatic or aliphatic monovalent to tetravalent organic group. Specifically,

[0019]

[Chemical 8]

[0020]

[Chemical 9]

And the like. Of these, the following are preferred.

[0022]

[Chemical 10]

R ⁴ may be an organic polymer and has the formula (II)
All of the organic polymers exemplified as the ether compound of can be preferably used. Next, the general formula (IV)

[0024]

[Chemical 11]

(R ¹ is hydrogen or a methyl group, R ⁵ is an aliphatic or aromatic organic group, and a is a positive integer). In formula (IV), R ⁵ represents an aliphatic or aromatic organic group, and specifically,

[0026]

[Chemical 12]

[0027]

[Chemical 13]

R ⁵ may be an organic polymer and has the formula (II)
All of the organic polymers exemplified in the above description can be preferably used. Specific examples of the component (A) include general formula (V)

[0029]

[Chemical 14]

(R ¹ is hydrogen or methyl group, R ² is carbon number 1
It is a divalent hydrocarbon group of -20 and may contain one or more ether bonds. R ⁶ is an aliphatic or aromatic organic group, and a is a positive integer. The compound which has the carbonate bond represented by these is mentioned. Wherein, R ² is the same as R ² in formula (II). Also, as R ⁶ ,

[0031]

[Chemical 15]

[0032]

[Chemical 16]

[0033]

[Chemical 17]

And the like. Of these, the following are particularly preferable.

[0035]

[Chemical 18]

R ⁶ may be an organic polymer and has the formula (II)
All of the organic polymers exemplified in the above description can be preferably used. When an organic polymer is used as the component (A), the method for introducing an alkenyl group into the polymer is
Although various proposals can be made, they can be roughly classified into a method of introducing after polymerization and a method of introducing during polymerization.

As a method of introducing an alkenyl group after the polymerization, for example, a polymer having a functional group such as a hydroxyl group or an alkoxide group at the terminal, main chain or side chain, an active group reactive with the above functional group, By reacting an organic compound having an alkenyl group, the alkenyl group can be introduced into the terminal, main chain or side chain. Examples of the organic compound having an active group and an alkenyl group reactive with the above functional group include C ₃ -C ₂₀ unsaturated such as acrylic acid, methacrylic acid, vinyl acetic acid, acrylic acid chloride, and acrylic acid bromide. Fatty acids, acid halides,
Acid anhydrides, C ₃ -C ₂₀ unsaturated fatty acid-substituted carbonic acid halides such as allyl chloroformate, allyl bromoformate, allyl chloride, allyl bromide, vinyl (chloromethyl) benzene, allyl (chloromethyl) benzene, allyl (Bromomethyl) benzene, allyl (chloromethyl) ether, allyl (chloromethoxy) benzene, 1-butenyl (chloromethyl) ether, 1-hexenyl (chloromethoxy) benzene, allyloxy (chloromethyl) benzene and the like can be mentioned.

As a method of introducing an alkenyl group during polymerization, for example, in the case of producing by a radical polymerization method, a vinyl monomer having an alkenyl group having a low radical reactivity in a molecule such as allyl methacrylate and allyl acrylate, allyl mercaptan, etc. An alkenyl group can be introduced into the main chain or terminal of the polymer by using the radical chain transfer agent.

The alkenyl group-containing organic polymer may be linear or branched and has a molecular weight of 500 to 50,000.
Any of the above can be preferably used, but 1000 to 200
Particularly preferred is 00. The alkenyl group may be at the molecular end or in the molecule, but when a rubber-like cured product is prepared using the composition of the present invention, the effective network chain length becomes longer at the molecular end. Therefore, it is preferable.

The component (B) of the present invention, which is an organic compound having at least two hydrosilyl groups in the molecule, is not particularly limited, but if a group containing a hydrosilyl group is specifically exemplified,

[0041]

[Chemical 19]

A group containing two silicon atoms such as

[0043]

[Chemical 20]

(In the formula, R is a group selected from H, OSi (CH ₃ ) ₃ and an organic group having 1 to 10 carbon atoms, and each R may be the same or different. M and n are positive. Is an integer and 2
≦ m + n ≦ 50)

[0045]

[Chemical 21]

(Where R is the same as above, m is a positive integer,
n, p, and q are 0 or a positive integer, and 1 ≦ m + n + p
+ Q ≦ 50)

[0047]

[Chemical formula 22]

(Where R is the same as above, m is a positive integer,
n is 0 or a positive integer, and examples thereof include a group derived from various linear, branched or cyclic polyvalent hydrogen siloxanes represented by 2 ≦ m + n ≦ 50). Among the above various hydrosilyl groups, the molecular weight of the group constituting the hydrosilyl group is preferably 500 or less from the viewpoint that the compatibility of the hydrosilyl group-containing compound of the present invention with the component (A) is less likely to occur. In view of the reactivity of the hydrosilyl group, the following are preferable.

[0049]

[Chemical formula 23]

(Where p is a positive integer, q is 0 or a positive integer, and 2≤p + q≤4).

[0051]

[Chemical formula 24]

When two or more hydrosilyl group-containing groups are present in the same molecule, they may be the same or different. The total number of hydrosilyl groups contained in the component (B) may be at least 2 in one molecule, but is preferably 2 to 15 and particularly preferably 3 to 12. When the compound containing a hydrosilyl group of the present invention is mixed with a compound containing an alkenyl group (component (A)) in the presence of a hydrosilylation catalyst to cure by a hydrosilylation reaction, the number of hydrosilyl groups is 2 or more. If the amount is small, curing failure often occurs. Also,
When the number of the hydrosilyl groups exceeds 15, (B)
The stability of the components becomes poor, and in addition, a large amount of hydrosilyl groups remain in the cured product even after curing, causing voids and cracks. The hydrosilyl group-containing compound as the component (B) is not particularly limited, but various compounds ranging from low molecular weight compounds to polymers can be used. Illustrating specifically, the formula (VI)

[0053]

[Chemical 25]

[0054] (wherein, X is a group having at least one hydrosilyl group of ^{the, R 1, R 2, R} 3 is, R ¹ in Formula (II),
The same thing as R ² and R ³ can be used. ) A compound having an ether bond represented by the formula:

[0055]

[Chemical formula 26]

[0056] (wherein, X is a group having at least one hydrosilyl group of ^{the, R 1, R 2, R} 4 is, R ¹ in formula (III),
The same thing as R ² and R ⁴ can be used. ) A compound having an ester bond represented by the formula:

[0057]

[Chemical 27]

[0058] In (wherein, X is a group having at least one hydrosilyl group of the, R ^1, R ⁵ may be used as the same respectively as R ^1, R ⁵ in formula (IV).) Table A hydrocarbon-based compound of formula (IX)

[0059]

[Chemical 28]

[0060] (wherein, X is a group having at least one hydrosilyl group of ^{the, R 1, R 2, R} 6 is, R ¹ in Formula (V), at
The same ones as R ² and R ⁶ can be used. The compound which has a carbonate bond represented by these can be mentioned.

When an organic polymer is used as the component (B), the polymer may be linear or branched and has a molecular weight of 5
Any of 00 to 50000 can be preferably used,
Those of 500 to 20,000 are particularly preferable. The hydrosilyl group as the component (B) may be present at the molecular end or in the molecule, but when a rubber-like cured product is produced using the composition of the present invention, it is more effective at the molecular end. It is preferable because the network chain length becomes long. The method for producing the component (B) is not particularly limited, and any method may be used. For example,
(I) An organic compound having a Si-Cl group in the molecule is replaced with LiAlH ₄ , Na
By treating with a reducing agent such as BH ₄ , the Si--Cl group in the compound is converted into Si.
A method of reducing to —H group, (ii) a method of reacting an organic compound having a functional group X in the molecule with a compound having a functional group Y that reacts with the functional group in the molecule and a hydrosilyl group at the same time, (iii ) A method of selectively hydrosilylating a polyhydrosilane compound having at least two hydrosilyl groups with respect to an organic compound having an alkenyl group to leave a hydrosilyl group in the molecule of the compound after the reaction can be considered. Of these, the method (iii) is particularly preferable.

As the combination of the components (A) and (B), any combination can be used.
One or both of the component and the component (B) are preferably organic polymers, and among them, the component (A) is preferably a polypropylene oxide polymer. When both the component (A) and the component (B) are low molecular weight compounds, the resulting cured product has a high crosslink density and becomes brittle, which is not preferable as a curable composition for a heat-resistant masking tape for printed circuit boards.

Examples of the hydrosilylation catalyst which is the component (C) of the present invention include platinum simple substance, solid platinum supported on a carrier such as alumina, silica, carbon black, chloroplatinic acid, chloroplatinic acid and alcohol, Complexes with aldehydes, ketones, etc., platinum-olefin complexes {for example, Pt (CH ₂ = C
_{H 2) 2 (PPh 3)} 2 Pt (CH 2 = CH 2) 2 Cl 2}; platinum - vinylsiloxane complex {for _{example, Pt n (ViMe 2 SiOSiMe 2} Vi) m, Pt [(MeV
iSiO) ₄ ] _m }; platinum-phosphine complex {for example, Pt (PPh
_{3) 4,} Pt (PBu _{3) 4};} platinum - phosphite complex (e.g., Pt [P (OPh _{3] 4)} (in the formula, Me represents a methyl group, Bu a butyl group, Vi represents a vinyl group, Ph is A phenyl group, m and n are integers), dicarbonyldichloroplatinum, and Ashby U.S. Pat. Nos. 3,159,601 and 3,
159662, a platinum-hydrocarbon composite, as well as Lamoreaux U.S. Pat. No. 322.
Mention may also be made of the platinum alcoholate catalysts described in 0972. Additionally, the platinum chloride-olefin composites described in Modic US Pat. No. 3,516,946 are also useful in the present invention. Examples of catalysts other than platinum compounds include RhCl (PPh ₃ ) ₃ , RhC
l ₃ , RhlAl ₂ O ₃ , RuCl ₃ , IrCl ₃ , FeCl ₃ , AlCl ₃ , PdCl ₂・ 2H
₂ O, NiCl ₂ , TiCl _{4 and the} like. These catalysts may be used alone or in combination of two or more. From the viewpoint of catalytic activity, chloroplatinic acid, platinum-olefin complex, platinum-acetylacetonate complex and platinum-vinylsiloxane complex are preferable.

The catalyst amount is not particularly limited, but (A)
10 ^-1 to 10 ^-8 mo for ¹ mol of alkenyl group in the component
It is recommended to use in the range of l. Preferably 10 ^-3 to 10 ^-6
It is recommended to use it in the mol range. If it is less than 10 ^-8 mol, curing will not proceed sufficiently. Further, the hydrosilylation catalyst is generally expensive and corrosive, and since a large amount of hydrogen gas may be generated and the cured product may foam, 10 ^-1 mol
It is better not to use more. In the present invention, the curable composition uses a noble metal catalyst for an alkenyl group.
Since it cures by the addition reaction of Si-H group, the curing rate is very fast, which is convenient for line production.

When the hydrosilyl group-containing compound which is the component (B) is produced by the selective hydrosilylation described above, the hydrosilylation catalyst is contained in the component (B) even after the reaction, so that its stability is generally good. However, when left for a long period of time or when moisture is mixed, conversion of Si-H groups to Si-OH groups occurs, and phenomena such as viscosity increase and gelation are observed. Therefore, it is preferable to include a storage stability improver in the component (B). As such a compound, a compound containing an aliphatic unsaturated bond, an organic phosphorus compound, an organic sulfur compound, a nitrogen-containing compound, a tin compound, an organic peroxide and the like can be preferably used. In particular,
Benzothiazole, thiazole, dimethyl maleate, 2
-Pentenenitrile, 2,3-dichloropropene and the like are mentioned, and thiazole is particularly preferable in terms of compatibility of pot life / rapid curing property, but not limited thereto. The use amount of the storage stability improver can be selected almost arbitrarily as long as it is uniformly dispersed in the component (A) and the component (B), but with respect to 1 mol of the Si-H group-containing compound of the component (B), It is preferably used in the range of 10 ⁻⁶ to 10 ⁻¹ mol. This is because if it is less than 10 ^-6 mol, the storage stability of the component (B) is not sufficiently improved, and if it exceeds 10 ^-1 mol, curing is inhibited. The storage stability improvers may be used alone or in combination of two or more.

As the surface tack modifier which is the component (D) of the present invention, an ester compound containing an ester of an unsaturated higher fatty acid and an alcohol as a main component, or a crystalline oligomer having a molecular weight of 1,000 to 20,000 is used. These have the significant effect of eliminating the surface tack after curing of the composition. Specific examples of the ester compound include higher unsaturated fatty acids such as oleic acid, linoleic acid, linolenic acid, eleostearic acid, licanoic acid, ricinoleic acid and arachidonic acid, and monohydric alcohols such as methanol and ethanol, ethylene glycol. Dihydric alcohols such as propylene glycol and butylene glycol, trihydric alcohols such as trimethylolpropane, glycerin and trimethylolethane, tetrahydric alcohols such as pentaerythritol, and hexahydric alcohols such as sorbid,
There is an ester compound consisting of a reaction condensate with an alcohol selected from organic silicon compounds having a hydroxyl group via an organic group bonded to a silicon atom. as mentioned above,
The component (D) may be produced by subjecting an unsaturated higher fatty acid and an alcohol to a condensation reaction, but it is practically inexpensive, convenient, and most preferable as the component (D) of the unsaturated higher fatty acid and glycerin. Natural unsaturated fats and oils such as linseed oil, tung oil, soybean oil, castor oil, dehydrated castor oil, fish oil, hempseed oil, cottonseed oil, tall oil and the like containing triglyceryl ester which is an ester as a main component.

As specific examples of the oligomers, the main chain skeleton thereof has crystallinity such as polycaprolactone or polytetramethylene glycol and has a molecular weight of 1000 to 2000.
0 oligomers. The amount of the component (D) used is 0.1 parts by weight per 100 parts by weight of the components (A) + (B).
A range of 1 to 50 parts by weight is desirable. The reason for this is that if the amount of component (D) is less than 0.1 parts by weight, the effect of eliminating surface tack after curing is not sufficient, and if it is more than 50 parts by weight, the physical properties of the composition after curing are significantly reduced. is there.

The curable composition of the present invention may optionally contain
Fillers, antioxidants, ultraviolet absorbers, pigments, surfactants, plasticizers, silane coupling agents and the like may be added as appropriate. Specific examples of the filler include fine silica powder, calcium carbonate, clay, talc, titanium oxide, zinc oxide, diatomaceous earth, barium sulfate, and carbon black.

[0069]

EXAMPLES Next, the composition of the present invention will be specifically described by way of examples, but the present invention is not limited to these examples. Synthesis Example 1 According to the method disclosed in JP-A-53-134095,
A polyoxypropylene having an allyl type olefin group at the end was synthesized. Polyoxypropylene glycol having an average molecular weight of 3000 and powdered caustic soda were stirred at 60 ° C., and bromochloromethane was added to carry out a reaction to increase the molecular weight. Next, add allyl chloride to give 11
The end was allyl etherified at 0 ° C. This was treated with aluminum silicate to synthesize a purified terminal allyl etherified polyoxypropylene. The average molecular weight of this polyether is 7960, 92% of the end of the iodine value
Was an olefin group. The viscosity by E type viscosity system is 13
It was 0 poise (40 ° C.).

Synthesis Example 2 A 200 ml four-necked flask was equipped with a cooling tube with a three-way cock.
A pressure equalizing dropping funnel, a thermometer, a magnetic tip, and a glass stopper were attached. Cyclic polyhydrogen siloxane under N ₂ atmosphere

[0071]

[Chemical 29]

(LS 8600, manufactured by Shin-Etsu Chemical Co., Ltd.) 12.
03 g (50 mmol) and 20 ml of toluene were charged into the flask. 1.76 g of 1,9-decadiene (20 mmo
l), 20 μl of a chloroplatinic acid catalyst solution (a solution of 1 g of H ₂ PtCl ₆ .6H ₂ O dissolved in 1 g of ethanol and 9 g of 1,2-dimethoxyethane) dissolved in 30 ml of toluene was charged into a dropping funnel. The flask was placed in an oil bath at 50 ° C., and the toluene solution was dropped into the flask over 2 hours under N ₂ atmosphere. When the IR spectrum was measured at the time when the reaction was further continued at 50 ° C. for 1 hour after the completion of the dropping, the absorption of the olefin near 1640 cm ⁻¹ had completely disappeared, so the reaction was ended at this time. After the reaction, the toluene solution was added to a saturated aqueous solution of ammonium chloride (1
After washing with 00 ml × 2) and exchanged water (100 ml × 1), Na ₂ S
Dry with O ₄ . Na ₂ SO ₄ was removed by filtration, benzothiazole (13 μl, 0.12 mmol) was added, and the volatile matter was removed by evaporation, and then degassed under reduced pressure at 80 ° C. to obtain 9.11 g of a colorless transparent liquid. It was The hydrosilyl group in the hydrocarbon compound was confirmed as a strong absorption at 2170 cm ^-1 . In addition, the proton intensity ratio between the Si— H peak and Si— CH ₃ at 300 MHz NMR (measured value 0.2
16) and the calculated intensity ratio, the compound has an average structure of the following formula [n = 1 (MW = 998) 53%, n = 2 (MW = 1377) 47%] It was found to be a mixture. Based on this, the number of Si--H groups in the unit weight was calculated to be 0.769 mol / 100 g.

Examples 1 to 8 Organic polymer (component (A)) obtained in Synthesis Example 1, Si—H group-containing compound (Component (B)) obtained in Synthesis Example 2, hindered phenolic antioxidant (Irganox 1010 manufactured by Ciba Geigy), 1% chloroplatinic acid catalyst solution ((C) component), (1.0 g of H ₂ PtCl ₆ .6H ₂ O dissolved in 99 g of ethanol), thiazole, and surface tack modification The amount of the substance (component (D)) shown in Table 1 was measured, mixed well, and then degassed under reduced pressure. The defoamed composition was poured into a mold having a thickness of about 2 mm and cured in an oven at 130 ° C. for 10 minutes to prepare a sheet-shaped cured product. The surface of the obtained sheet was checked for surface tack by touching with fingers, and the results are shown in Table 1.

Comparative Example 1 The same procedure as in Example 1 was carried out except that the surface tack modifier was not used, and the results are also shown in Table 1.

[0075]

[Table 1]

[0076]

As is clear from the results shown in Table 1, the curable composition of the present invention significantly improves the surface tack after curing. Since the surface tack is greatly reduced, it is useful for a wide range of applications such as a sealing material, a sealing agent, a paint, a coating agent, a casting rubber and a heat-resistant masking tape for a printed circuit board.

─────────────────────────────────────────────────── ─── Continuation of the front page (51) Int.Cl. ⁵ Identification code Office reference number FI technical display location C09K 3/10 G 9159-4H

Claims (3)

[Claims] 1. A curable composition comprising the following four components (A) to (D) as main components; (A) a compound having at least one alkenyl group in the molecule, (B) at least 2 in the molecule. A compound having one hydrosilyl group, (C) a hydrosilylation catalyst, (D) a surface tack modifier. 2. The composition according to claim 1, further comprising a storage stability improver. 3. The compound having at least one alkenyl group in the molecule has a number average molecular weight of 500 to 50,000.
The composition according to claim 1, which is an oligomer composed of the polyether main chain.