JP3301135B2 - Radiation-curable adhesive organopolysiloxane 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 radiation-curable adhesive organopolysiloxane composition and, more particularly, to a radiation-curable organopolysiloxane composition having excellent adhesion to a plastic substrate and excellent curability in deep areas.

[0002]

2. Description of the Related Art In recent years, a large number of silicone compositions which cure to a rubbery state in a short time by radiation have been reported. For example, Japanese Patent Application Laid-Open No. 61-145227 describes a product obtained by adding an acrylate or methacrylate containing an isocyanate group to an organopolysiloxane having an amino group at the molecular terminal. However, such an oligomer alone has insufficient adhesiveness, and in particular, P
What satisfy | fills the adhesiveness with respect to engineering plastics, such as BT and PPS, is not yet known. In addition, there has been conventionally known a composition in which a radiation-curable monomer is used in combination with a radiation-curable oligomer to improve the adhesiveness, but this is not satisfactory in its performance. An object of the present invention is to solve the problems of the prior art, and at the same time as curing, a radiation-curable organopolypropylene having good adhesion to various engineering plastics as well as inorganic materials such as glass and glass, and deep curing. It is to provide a siloxane.

[0003]

Of the present invention SUMMARY OF] (a) a curable organopolysiloxane 100 parts by weight of the following with the radiation-curable adhesive polyorganosiloxane compositions both ends of the molecule a (meth) acrylic group, (b ) (Meth) acrylic acid
0.1 to 10 parts by weight; (c) 0.1 to 50 parts by weight of the following (meth) acrylate;
It is characterized by comprising from 0.1 to 10 parts by weight.

[0004] Te present invention smell, a "(meth) acrylic"
The term is a generic term for “acryl” and “methacryl”.

[0005] The main component of the composition of the present invention is a curable organopolysiloxane having (meth) acrylic groups at both molecular terminals. Usually, an organopolysiloxane having amino groups at both molecular terminals has an isocyanate group-containing (meth) group. It can be easily obtained by reacting acrylate or (meth) acrylic anhydride.

In the above, the organopolysiloxane having an amino group at both molecular terminals is not particularly limited, and any known one can be used as appropriate. Usually, a polysiloxane represented by the following general formula is used.

[0007]

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Here, R ₁ R ₄ is a divalent hydrocarbon group, wherein R ₂ and R ₃ are alkyl groups such as methyl group, ethyl group and propyl group, cycloalkyl groups such as cyclohexyl group, vinyl group and allyl. An alkenyl group such as a group, an aryl group such as a phenyl group or a tolyl group, a trifluoropropyl group in which part or all of the hydrogen atoms bonded to the carbon atoms of these groups have been substituted with a halogen atom, a cyano group, or the like; The same or different, substituted or unsubstituted monovalent hydrocarbon groups selected from a group, a cyanomethyl group and the like, R ₅ is a hydrogen atom or a monovalent hydrocarbon group, m is an integer of 0 to 4, n is 50 to 100
It indicates an integer of 00.

Specific examples of the isocyanate group-containing (meth) acrylate to be added to both terminal amino groups of the polysiloxane are methacryloyl isocyanate,
-Isocyanate ethyl methacrylate, isopropenyl-2,2-dimethylbenzyl isocyanate, and two isocyanate groups such as 2,4-tolylene diisocyanate, 2,6-tolylene diisocyanate, 1,5-naphthalene diisocyanate, and isophorone diisocyanate. There is an isocyanate group-containing (meth) acrylate obtained by reacting the compound having the above with a (meth) acrylate having a hydroxyl group such as 2-hydroxyethyl methacrylate or 2-hydroxypropyl methacrylate.

[0010] The addition reaction is usually carried out by mixing the amino group-containing organopolysiloxane with the amino group in such an amount that the isocyanate group sufficiently reacts with the amino group. Usually, 2 mol or more of the latter is added to 1 mol of the former, and the reaction is carried out under slight heating such as around 50 ° C.

The (meth) acrylic anhydride is also usually reacted with an amino group in an equimolar amount in the same manner as the above isocyanate compound. The reaction is carried out under a slight heating of about 50 ° C., and in some cases, N-methylimidazole or the like may be used as a catalyst.

Specific examples of the compound synthesized by the above reaction include compounds as exemplified by the following formula.

[0013]

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The organopolysiloxane thus obtained is excellent in adhesiveness and curability in the deep part, and its characteristics are further improved by combination with the following components.

First, as a photopolymerization catalyst, dimethoxyacetophenone, 1-hydroxycyclohexylphenylketone, diethoxyacetophenone, fusetophenone, propiophenone, benzophenone, xanthol, fluorein, benzaldehyde, anthraquinone, triphenylamine, carbazole, Methylacetophenone, 4-methylacetophenone, 3-bentylacetophenone, 4-methoxyacetophenone, 3-bromoacetophenone, p-diacetylbenzene, 3-methoxybenzophenone, 4-allylacetophenone, 4-methylbenzophenone, 4-chloro-4-benzyl Benzophenone, 3-chloroxantone, 3,9-dichloroxantone, 3-chloro8-nonylxantone, benzoin, benzoinmethone Ether, benzoin butyl ether, bis (4-dimethylaminophenyl) ketone, benzyl methoxy ketal, 2-chlorothioxanthone tones and the like. The addition amount of the photopolymerization catalyst is only required to slightly sensitize the system.
It is sufficient to use 0.01 to 10 parts by weight, preferably 0.1 to 10 parts by weight, per 100 parts by weight.

Next, the (meth) acrylic acid added to the present composition improves the photocurability of the composition and, in particular, metal,
It is an essential component for imparting adhesion to glass and the like. If the addition amount is too small, the adhesiveness is not sufficiently exhibited, and if it is too large, there is a problem of toxicity and the like, and 0.1 to 10 parts by weight is used per 100 parts by weight of the organopolysiloxane.

Next, the (meth) acrylic acid ester added to the present invention not only lowers the viscosity of the composition, but also improves the mechanical strength, but is particularly excellent in adhesion to a plastic substrate. It is an essential component for imparting properties. In the present invention, (meth) acrylic acid ester having such a function is tetrahydrofurfuryl (meth) acrylate, cyclohexyl (meth) acrylate, 2-ethylhexyl (meth) acrylate, glycidyl (meth) acrylate, lauryl (meth) acryle.
, Neopentyl glycol di (meth) acrylate, dicyclopentenyl (meth) acrylate, dicyclopentenyloxyethyl (meth) acrylate and tricyclo (5,2,1,0,2,6) decanyl (meth)
(Meth) acrylic selected from the group consisting of acrylates
Use acid esters. If the added amount is too small, the adhesiveness is not sufficient, and if the added amount is too large, there is a problem that heat resistance and the like are reduced. Organopolysiloxane 100
0.1 to 50 parts by weight, preferably 1 to 20 parts by weight
Parts by weight.

In the present invention, if necessary, various additives,
For example, various inorganic fillers such as fumed silica for the purpose of improving mechanical properties, thixotropy-imparting agents such as polyethylene glycol and its derivatives, pigments, dyes, antioxidants, antioxidants, antimony oxide, and flame retardants such as paraffin chloride. , Boron nitride, aluminum oxide and other thermal conductivity improvers, and various additives such as rust preventives may be used in combination.

[0019]

Synthesis Example 1 0.84 g of 2-isocyanatoethyl methacrylate was added to 100 g of dimethylpolysiloxane having a viscosity of 8800 cP at 25 ° C. and both terminals of which are 3-aminopropyldimethylsilyl groups at 25 ° C., and mixed at room temperature for 10 minutes to obtain a radiation-curable composition. A product (P-1) was obtained.

[0020]

[Synthesis Example 2] 100 g of dimethylpolysiloxane having a viscosity of 8800 cP at 25 ° C. and having 3-aminopropyldimethylsilyl groups at both molecular ends was added to 100 g of methacrylic anhydride.
8 g was added and mixed at room temperature for 10 minutes to obtain a radiation-curable composition (P-2).

[0021]

[Synthesis Example 3] Both ends of molecule are blocked with silanol 25
Viscosity at 100 ° C in 100 g of dimethylpolysiloxane
Methacryloxypropyldimethylchlorosilane 1.1
g, 0.1 g of triethylamine as a catalyst, 100
The reaction was carried out at a temperature of 3 ° C. for 3 hours to obtain a radiation-curable composition (P-3).

[0022]

Examples 1 to 4 and Comparative Example 1 Table 1 shows the results obtained by blending various compounds with the above-mentioned polysiloxanes (P-1, P-2, P-3) and examining the adhesion and physical properties. However, the silica in the table is Nippon Aerosil Esilil R-972,
The photoinitiator is diethoxyacetophenone, M1 is tetrahydrofurfuryl methacrylate, and M2 is lauryl methacrylate. At the time of curing, ultraviolet rays were irradiated at 150 mw / cm ² × 30 seconds with a 4 kW high-pressure mercury lamp.

[0023]

[Table 1]

[0024]

The composition of the present invention can be cured to a deep portion in a short time by irradiating ultraviolet rays, and can adhere well to metals, glass and various engineering plastics, and can be used for adhesives, sealing agents, and casting. Can be used usefully.

Continuation of front page (58) Field surveyed (Int. Cl. ⁷ , DB name) C08F 290/00-290/14 C08F 299/00-299/08 C09J 1/00-201/10 C09K 3/10

Claims (1)

(57) [Claims] (1) An amino acid having amino groups at both ends of the molecule.
Luganopolysiloxane containing isocyanate groups (meta)
Reacts acrylate or (meth) acrylic anhydride
Has (meth) acrylic groups at both ends of the molecule
100 parts by weight of a curable organopolysiloxane, (b)
0.1 to 10 parts by weight of (meth) acrylic acid, (c) tetra
Hydrofurfuryl (meth) acrylate, cyclohexyl
(Meth) acrylate, 2-ethylhexyl (meth)
Acrylate, glycidyl (meth) acrylate, lau
Ril (meth) acrylate, neopentyl glycol di
(Meth) acrylate, dicyclopentenyl (meth) a
Acrylate, dicyclopentenyloxyethyl (meth)
Acrylate and tricyclo (5,2,1,0,2,
6) selected from the group consisting of decanyl (meth) acrylate
0.1 to 50 parts by weight of (meth) acrylic acid ester
And (d) a radiation curable adhesive organopolysiloxane composition comprising 0.01 to 10 parts by weight of a photoinitiator.