JPH0649363A - Room-temperature-curable organopolysiloxane composition - Google Patents

Abstract

PURPOSE:To provide a room-temperature-curable composition which is excellent in rapid curability, depth curability and workability and can give a cured product excellent in rubbery properties. CONSTITUTION:The composition comprises an organopolysiloxane terminated with a hydrolyzable silyl group, an epoxy compound, an organic carbonyl compound, an organic amino compound and a curing catalyst for the above organopolysiloxane.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention is used as a sealing material for buildings, a coating material, a sealing material for electric and electronic parts, a potting material, a fiber treating agent, an adhesive for automobiles, constructions, electric / electronics, etc. Useful room temperature curable organopolysiloxane compositions.

[0002]

2. Description of the Related Art Condensation-curable room-temperature-curable organopolysiloxane compositions are used as adhesives for parts where seismic properties are required, for example, in the fields of electric / electronic and building materials. In such applications, the curing speed is fast,
It is required that the adhesive be strong and that the cured product be an elastic body.

As a condensation-curing room-temperature-curing organopolysiloxane composition, a one-pack type composition has been conventionally used in which the amount of the crosslinking agent is reduced as much as possible and the rate of crosslinking is improved by hydrolysis of the hydrolyzable group. A two-pack type in which a crosslinking agent and a curing agent are separately packaged is known. However, the former has a high curing rate from the surface but requires a considerable amount of time for deep curing, and the latter is excellent in deep curing, but the volume ratio or weight ratio for mixing the two liquids is not 1: 1. Therefore, there is a drawback that the workability of weighing and mixing is poor and it is difficult to adapt to an automatic mixer. In addition, the two-pack type has a narrow range of crosslinker and curing agent, which is necessary to completely cure it to the deep part, so the addition amount is strictly controlled, or water is added as the deep part curing agent. It was necessary to do.

[0004]

SUMMARY OF THE INVENTION Therefore, an object of the present invention is to provide a room temperature curable composition which is excellent in fast curability, deep curability and workability.

[0005]

The present invention provides a curable organopolysiloxane composition containing a hydrolyzable silyl group-containing organopolysiloxane and an epoxy compound as main components, the former hydrolyzable silyl group-containing organopolysiloxane. By generating water necessary for crosslinking and curing the siloxane in the composition by reacting an organic compound having a carbonyl group with an organic compound having a primary amino group,
The above problems have been solved.

That is, according to the present invention, (A) an organopolysiloxane having a molecular chain end blocked with a hydrolyzable silyl group, (B) an epoxy compound, (C) an organic compound having a carbonyl group, (D) An organic compound having an amino group, and (E)
A room temperature curable composition comprising a curing catalyst of component (A) is provided.

(A) Hydrolyzable silyl group-containing organopolysiloxane This organopolysiloxane has a molecular chain terminal blocked with a hydrolyzable silyl group and is the main component of the composition of the present invention. Examples of the organopolysiloxane include those represented by the general formula (1):

[Chemical 1] (In the formula, R ¹ , R ² and R ³ may be the same or different, alkyl groups such as methyl group, ethyl group and propyl group, cycloalkyl groups such as cyclohexyl group, alkenyl groups such as vinyl group and allyl group, It represents a substituted or unsubstituted monovalent hydrocarbon group such as an aryl group such as a phenyl group and a tolyl group, or a hydrogen atom of these groups partially substituted with a halogen atom, and X represents isopropenyl. Alkenyloxy groups such as oxy group and isobutenyloxy group; ketoxime groups such as dimethylketoxime group and methylethylketoxime group; alkoxy groups such as methoxy group, ethoxy group, butoxy group; acyloxy groups such as acetoxy group; N-butyl Amino group, amino group such as N, N-diethylamino group; Aminoxy group such as N, N-diethylaminoxy group; N- An amide group such as a methylacetamide group; a hydrolyzable group selected from a carboxyl group and the like, 1 and m may be the same or different, each represents an integer of 0 to 2, and n is an integer of 10 or more.) It is shown by. When there are a plurality of hydrolyzable groups at the terminal of the molecule, those hydrolyzable groups may be the same or different.

Among the organopolysiloxanes represented by the general formula (1), those containing an alkenyloxy group as X are preferable in that the ketone as the component (C) is produced by hydrolysis and subsequent condensation. This makes the component (C)
It is possible to reduce the amount of addition of and to control the amount of condensate formed during hydrolysis. The viscosity of the organopolysiloxane of the component (A) is preferably 25 to 1,000,000 cSt at 25 ° C, more preferably
It is 1,000 to 100,000 cSt.

(B) As the epoxy compound component (B), known epoxy compounds can be used without particular limitation. For example, glycidyl ether-bisphenol A type epoxy resin, glycidyl ether-bisphenol F type epoxy resin, glycidyl ether-tetrabromobisphenol A type epoxy resin,
Novolac type epoxy resin, m-aminophenol type epoxy resin, diaminodiphenylmethane type epoxy resin, urethane modified epoxy resin, various alicyclic epoxy resins, various aliphatic epoxy resins, N, N-diglycidylaniline, triglycidyl isocyanurate, Polyalkylene glycol glycidyl ether, polysiloxane glycidyl ether, polysilane glycidyl ether, epoxy-modified siloxane compound (KF105, X-22-163A, X-
22-163B, X-22-163C, KF100T, KF101, X-22-169AS,
X-22-169B, KF102, KF103. Shin-Etsu Chemical Co., Ltd. product name) and the like. Among these, Epicote 828 and 82
7 (trade name of Yuka Shell Co., Ltd.), KF100T and KF102 (trade name of Shin-Etsu Chemical Co., Ltd.) are preferable. Further, in order to smoothly proceed the three-dimensional crosslinking and obtain a good cured product, it is preferable to contain at least two epoxy groups in the molecule.

This epoxy compound (B) is a component (A): a component (B) when the sum of the component (A) and the component (B) is 100 parts by weight.
Is preferably blended in the range of 1:99 to 99: 1, 8
The range of 0:20 to 50:50 parts by weight is more preferable.

(C) Carbonyl Group-Containing Organic Compound The organic compound having a carbonyl group (C═O) reacts with the organic compound having a primary amino group (NH ₂ group) of the component (D) to produce a deep curing agent. Produces water that acts as. Examples of such a carbonyl group-containing compound include ketones such as acetone, methyl ethyl ketone, acetophenone, and cyclohexanone, ethyl acetate, butyl acetate, methyl propionate, ethyl acrylate, esters such as butyrolactone, dimethylformamide, diethylacetamide, butyrolactam, and the like. Amides, carboxylic acids such as acetic acid, propionic acid and benzoic acid, silane coupling agents having a carbonyl group-containing site of these compounds as a functional group, various polymers and oligomers having a carbonyl group. Among these compounds, acetone and cyclohexanone are preferable.

The above carbonyl group-containing compounds may be used either individually or in combination of two or more. The blending amount of this component (C) in the composition is 0.001 to 100 parts by weight of the total of the above components (A) and (B).
The range of 1 mol is preferable, and the range of 0.01 to 0.1 mol is particularly preferable. If the compounding amount is too small, the composition does not exhibit sufficient deep-curing property at the time of curing, and if it is too large, the elastic body obtained by curing the composition is softer than the appropriate amount and the strength is lowered. Becomes

(D) Primary amino group-containing organic compound The component (D) is a carbonyl group-containing organic compound as described above.
It has both the property of reacting with (C) to generate water which acts as a deep curing agent and the property of acting as a curing agent for the epoxy compound of component (B). Examples of the organic compound having a primary amino group include methylamine, ethylamine, butylamine, ethylenediamine, triethylenetetramine, alinine, primary amines such as 4,4′diaminodiphenyl ether, and γ-aminopropyltriethoxysilane. Amino group-containing organosilicon compounds such as silane coupling agents having a primary amino group as a functional group, aliphatic polyamines, primary amino group-containing alkylene oxide polymers, primary amino group-containing polysiloxanes, and the like. Examples thereof include polymers and oligomers having a primary amino group.

Of these, the amino group-containing organosilicon compound is preferable in that particularly good rubber elastic properties can be obtained. As an example of such an amino group-containing organic silicon compound, the basic skeleton is represented by the general formula (2):

[Chemical 2] (In each formula, R ⁶ is an alkyl group such as a methyl group or an ethyl group,
(Aryl group such as phenyl group, alkenyl group such as vinyl group and allyl group, alkoxy group such as trifluoropropyl group, methoxy group, ethoxy group and iropropoxy group, amino group, aminoxy group, acetoxy group, etc. are exemplified.) It is composed of one kind or two or more kinds of structures exemplified by the above, and has a primary amino group bonded to its basic skeleton through an appropriate linking group. The structure of the amino group-containing organosilicon compound may be linear, branched, cyclic, or a combination of these structures, and the molecular weight of these is not particularly limited. In particular,

[Chemical 3]

[Chemical 4] In addition to those represented by structural formulas such as KF393, KF859,
KF86, KF861, KF867, KF869, KF880, KF8002, KF800
Examples of commercially available products are trade names (Shin-Etsu Chemical products) of 4, KF8005, KF864, KF865, KF868, and KF8003.

The above-mentioned amino group-containing organic compounds may be used alone or in combination of two or more. In particular, in consideration of the curing rate of the composition, a compound having one primary amino group in one molecule is used in combination with a compound having two or more primary amino groups in one molecule. preferable. The blending amount of this component (D) is preferably in the range of 0.01 to 200 parts by weight with respect to 100 parts by weight of the component (B). In particular, the curing rate of the composition, long-term storability in an uncured state, economical efficiency, etc. are taken into consideration. Then, the range of 5 to 50 parts by weight is preferable.

For the purpose of accelerating the curing of the epoxy compound as the component (B), it is possible to add a compound capable of curing the epoxy compound in addition to the above component (D), if necessary. . Specifically, primary amine-free compounds such as aliphatic polyamines, polyamide resins, dicyandiamide, imidazole tertiary amines, amino group-containing organosilicon compounds and the like, acid anhydride compounds, phenolic resins, mercaptan compounds , Dicyandiamide, Lewis acid complex compounds and the like. These may be used alone or in combination of two or more.

Of these, the amino group-containing organosilicon compound is particularly suitable for exhibiting rubber elasticity. An example of such an amino group-containing organosilicon compound is that the basic skeleton is composed of one kind or two or more kinds of structures exemplified by the above-mentioned general formula (2) and the like, and the primary amino group is directly attached to the basic skeleton. Or linked via a suitable linking group. The amino group is a primary amino group protected by a Schiff base, the second
It may be either a primary or tertiary amino group. The structure of the amino group-containing organosilicon compound may be linear, branched, cyclic, or a combination of these structures, and the molecular weight of these is not particularly limited.

The basic form of the amino group bonded to the above basic skeleton is, for example,

[Chemical 5] And the form of the piperidine group. These amino groups are bonded to the above-mentioned basic skeleton via a linking group which is alicyclic, aromatic, aliphatic or a combination thereof. Specifically preferred is

[Chemical 6]

[Chemical 7] Etc. can be illustrated. The compounding amount when adding a compound capable of curing these epoxy compounds, the component (B)
0.01 to 20 combined with the blending amount of component (D) per 100 parts by weight
The range of 0 parts by weight is preferable, and in consideration of the curing rate of the composition, long-term storage stability in an uncured state, economical efficiency, etc., it is 5 to 50.
A range of parts by weight is preferred.

(E) Hydrolyzable silyl group-containing organopoly
The curing catalyst component (E) for the siloxane (A) is a curing catalyst for the organopolysiloxane (A), and for example, tin-based catalysts and titanium-based catalysts can be used. Specifically, tin naphthenate, tin caprylate, tin oleate, dibutyltin diacetate, dibutyltin dioctate, dibutyltin dilaurate, dibutyltin dioleate, diphenyltin diacetate, dibutyltin oxide, dibutyltin dimethoxide, dibutylbis (triethoxysiloxy). ) Tin, organotin compounds such as dibutyltin benzyl malate, tetraisopropoxy titanium, tetra-n-butoxy titanium, tetrabis (2-ethylhexoxy) titanium, dipropoxybis (acetylacetonato) titanium,
Examples thereof include titanic acid esters such as titanium isopropoxyoctylene glycol and titanium chelate compounds.

Further, a basic compound may be used in combination in order to enhance the activity of the catalyst. Specifically, amines such as octylamine and laurylamine, imidazoline which is a cyclic amine, tetrahydropyrimidine, 1,8-diazabicyclo (5,4,0) undecene-7 and guanidinepropyltris (trimethylsiloxy) silane. Examples thereof include guanidyl group-containing silane compounds and partial hydrolysates thereof, and guanidyl group-containing siloxanes. This catalyst
The compounding amount of (E) is 0.1 to 10 with respect to 100 parts by weight of the component (A).
A range of 0.5 to 5 parts by weight is preferable, particularly considering the curing rate, long-term storage stability in an uncured state, and economical efficiency.

Other Components In addition to the components (A) to (E), various components can be added to the room temperature curable composition of the present invention, if necessary. For example, storage stabilizers such as methyltrimethoxysilane, methyltripropenoxysilane, vinyltributanoxime silane, and methyltriacetoxysilane, fumed silica, precipitated silica, aluminum oxide, quartz powder, carbon powder, talc and bentonite. Reinforcing agent, asbestos, fibrous filler such as glass fiber and organic fiber, coloring agent such as pigment and dye, heat resistance improving agent such as red iron oxide and cerium oxide, cold resistance improving agent, dehydrating agent, γ-glycidoxypropyl Examples thereof include an adhesion improver such as triethoxysilane, and a liquid reinforcing agent such as a reticulated polysiloxane composed of triorganosiloxy units and SiO ₂ units. These may be added in predetermined amounts as needed.

Preparation of Composition The composition of the present invention is a one-part composition by uniformly mixing the required amounts of each of the components (A) to (E) and optional components added as necessary in a dry atmosphere. Obtained as a mold room temperature curable composition. At this time, the component (C) or (D) is mixed in a microencapsulated state to give a one-pack type room temperature curable composition having improved storage stability. It is also possible to use a two-liquid type in which the two liquids are separately packaged and mixed at the time of use. In the case of the two-liquid type, it is easy to set the mixing ratio of the two liquids to 1: 1 and workability is good.

Uses This composition is, for example, a sealing material for buildings, a coating material, a sealing material for electric and electronic parts, a potting material, a fiber treating agent, an automobile, and a building from the viewpoint of its rapid curing property and deep curing property. It is useful as an adhesive for electric appliances and electric appliances.
In particular, it can be effectively used as an oil seal material for automobiles, which is required to have high rapid curability and deep curability in the manufacturing process, and a sealing material for electric and electronic, and a potting material, which have recently been required to rationalize the process.

[0024]

When the composition of the present invention is cured, the carbonyl group contained in the component (C) and the primary amino group contained in the component (D) are
The following formula:

[Chemical 8] And reacts to produce water, which is used as a deep-curing agent in the system to significantly improve the fast-curing property and the deep-curing property of the composition. this is,
In the case of packing two liquids and mixing them at the time of use, there is an advantage that it is easy to mix the two liquids in a ratio of 1: 1, and further, a component to be added to generate water, that is, Since both the organic compound having a C = O group and the organic compound having a primary amino group are easily available, they are excellent in practicality.

[0025]

EXAMPLES Examples of the present invention will be given below.

Examples 1 to 6; Comparative Examples 1 and 2 In each of the Examples and Comparative Examples, the viscosity (25%) was obtained by blocking both ends of the molecular chain with vinyldiisopropenyloxysilyl groups.
Dimethylpolysiloxane (polymer A) with a temperature of 20,000 cSt, dimethylpolysiloxane (polymer B) with a viscosity (25 ° C) of 8,000 cSt, with both ends of the molecular chain blocked with vinyldiisopropenyloxysilyl groups. Both ends of the chain were blocked with trimethoxysilyl groups, and the viscosity (25 ° C) was
A composition was prepared by mixing 8,000 cSt dimethylpolysiloxane (Polymer C) in the compounding ratio shown in Table 1 with the components shown in the table. Next, each of the obtained compositions was molded into a sheet having a thickness of 2 mm and then left in an atmosphere of 20 ° C. and 60% RH. After 24 hours, the physical properties of the obtained cured product,
That is, hardness, tensile strength and elongation were measured according to JIS-K-6301. The hardness was measured using a spring type hardness tester type A. The results obtained are shown in Table 1. Further, the deep-part curability was evaluated by placing the composition in a plastic container having a depth of 10 mm and measuring the deep-part cured thickness (thickness from the surface of the cured layer) after 2 hours.

[0027]

[Table 1]

[0028]

The composition of the present invention is excellent in quick-curing property, deep-curing property and workability, and the cured product obtained is also excellent in rubber physical properties.

Continuation of the front page (51) Int.Cl. ⁵ Identification number Internal reference number FI Technical display location C08K 5/54 5/56 (72) Inventor Masatoshi Arai 1-person, Hitomi Hitoshi, Matsuida-cho, Usui-gun, Gunma 10 Shin-Etsu Chemical Industry Silicone Electronic Materials Technology Laboratory

Claims (4)

[Claims] 1. An organopolysiloxane having (A) a molecular chain end blocked with a hydrolyzable silyl group, (B) an epoxy compound, (C) an organic compound having a carbonyl group, and (D) an organic compound having an amino group. And (E) a room temperature curable composition comprising the curing catalyst of component (A). 2. The composition according to claim 1, wherein the hydrolyzable silyl group of the component (A) produces a ketone by hydrolysis. 3. The composition according to claim 1, wherein the organic compound having an amino group as the component (D) is an organosilicon compound having two or more primary amino groups in one molecule. 4. A cured product obtained by curing the composition according to claim 1.