JPH05271527A - Cold-curing composition - Google Patents

Abstract

PURPOSE:To obtain the subject composition having effectively improved curability, giving a cured material free from surface tackiness and having high surface strength and useful as a sealing material for building, etc., by compounding a curing catalyst to a main material composed of a specific silanemodified alkylene oxide polymer. CONSTITUTION:The objective cold-curing composition having effectively improved curability and giving a cured material free from surface tackiness and having high surface strength can be produced by compounding (A) a silane- modified alkylene oxide polymer containing at least one group of formula [R is H or lower alkyl R<1> to R<4> are H or (substituted) univalent hydrocarbon group; R<5> is (substituted}univalent hydrocarbon group; R<6> is bivalent organic group; (a) is integer of 1-3] in one molecule and produced by adding gamma-(acryloxypropyl)trimethoxysilane to a toluene solution of a polypropylene glycol having a molecular weight of 11,000 and molecular chain terminals blocked with the group of the formula OCH2CH2NH2 and reacting the components at 120 deg.C for 4hr with (B) a curing catalyst (e.g. dibutyltin dilaurate).

Description

Detailed Description of the Invention

[0001]

FIELD OF THE INVENTION The present invention relates to a room temperature curable composition containing a silane-modified alkylene oxide polymer as a main component.

[0002]

2. Description of the Related Art Various types of room temperature curable compositions containing a silane-modified alkylene oxide polymer as a main component are already known (for example, Japanese Patent Publication No. 61-1858).
No. 2, No. 61-29379, No. 61-18569,
60-57393, 61-36008, 62
No. 34763, No. 62-34764, etc.), all of these compositions form a siloxane bond in the presence of moisture and crosslink to form a cured product. A room temperature curable composition containing an alkylene oxide polymer having a silanol group introduced at the molecular end as a main material is also known (for example, Japanese Patent Publication Nos. 57-52368 and 58-1).
0430, 59-9579, 61-5482.
No. 63-52059, etc.), these compositions contain a silane compound having at least two hydrolyzable groups and crosslink in the presence of moisture to form a siloxane bond. And cure. The room temperature curable composition described above is mainly used as a sealing material for construction, but when it is used as a sealing material for joints, for example, an external force is applied due to environmental conditions such as temperature change, earthquake, vibration, and wind. In order to maintain the waterproof function even in the case of being exposed, the physical properties after curing are required to have a low modulus and a large elongation.

[0003]

However, the above room-temperature-curable composition has the drawback of poor surface curability when used as a building sealing material, and as a result, it adheres to the surface of the cured product. There are problems such as the feeling that remains forever and the surface strength of the cured product decreases. Therefore, an object of the present invention is to provide a room temperature curable composition containing a silane-modified alkylene oxide polymer having an improved curing property as a main material.

[0004]

According to the present invention, (A)
The following general formula (1),

[Chemical 2] [In the formula, R represents a hydrogen atom or a lower alkyl group,
R ^{1 to} R ⁴ may be the same or different and each is a hydrogen atom or an unsubstituted or substituted monovalent hydrocarbon group, and R ⁵ may be the same or different and may be an unsubstituted or substituted monovalent hydrocarbon group. Is a divalent hydrocarbon group, R ⁶ is a divalent organic group, and a is an integer of 1 to 3,
Provided is a room temperature curable composition comprising a silane-modified alkylene oxide polymer having at least one silane in one molecule, and (B) a curing catalyst.

(A) Silane-modified alkylene oxide polymerization
Body In the composition of the present invention, the silane-modified alkylene oxyto polymer used as the main material has at least one unit represented by the general formula (1) bonded to the main chain composed of alkylene oxy units. There is something. Here, as the alkyleneoxy unit constituting the main chain, for example, —CH ₂ CH ₂ O—, —CH ₂ CH (CH ₃ ) O—, —
_{CH 2 CH (C 2 H 5} ) O -, - (CH 2) 4 O- , etc. can be exemplified, of course, be they constitute two or more kinds in combination backbone. In the present invention, it is particularly desirable that the main chain be composed of —CH ₂ CH (CH ₃ ) O—. Further, the silane-modified alkylene oxide polymer has units other than the above-mentioned alkyleneoxy unit and the unit represented by the general formula (I).
For example, it may be contained within the range of 3 mol% or less. However, it is necessary that such a unit does not have an atomic group that inhibits the reaction for introducing the unit represented by the general formula (1) into the molecule, and a suitable example thereof is It is as follows.

[Chemical 3]

[Chemical 4]

[Chemical 5]

[Chemical 6]

In the above general formula (1), R is a hydrogen atom or a lower alkyl group, and the lower alkyl group is a group having 4 or less carbon atoms such as a methyl group, an ethyl group, a propyl group and a butyl group. It can be illustrated. The most preferable one as R is a hydrogen atom. Also R ¹ ~
R ⁴ is a hydrogen atom or an unsubstituted or substituted monovalent hydrocarbon group, and examples of the monovalent hydrocarbon group include an alkyl group such as a methyl group, an ethyl group, a propyl group and a butyl group; a cyclohexyl group. A cycloalkyl group such as; an alkenyl group such as a vinyl group or an allyl group; an aryl group such as a phenyl group or a tolyl group; an aralkyl group such as a benzyl group or a phenylethyl group; and a part or all of hydrogen atoms of these groups. Groups substituted with halogen atoms, alkoxy groups, etc., such as chloromethyl group, 3,3,3-trifluoropropyl group, methoxyethyl group, ethoxyethyl group, etc .;
And the number of carbon atoms is 1 to 10, especially 1
The thing of -6 is preferable. In the present invention, most preferably, R ¹ and R ² are hydrogen atoms, R ³ is a hydrogen atom or a methyl group, and R ⁴ is a hydrogen atom, an alkyl group or an alkoxy-substituted alkyl group. ..

Further, R ⁵ is an unsubstituted or substituted monovalent hydrocarbon group, and specific examples thereof include the same groups as the monovalent hydrocarbon groups mentioned above for R ^{1 to} R ^4. .. In the present invention, most preferable ones as R ⁵ are an alkyl group, an alkenyl group and an aryl group. R ⁶ is a divalent organic group, and examples thereof include alkylene groups such as methylene group, ethylene group, propylene group, methylethylene group, tetramethylene group, hexamethylene group, and arylene groups such as phenylene group and tolylene group. And is most preferably an alkylene group having 1 to 3 carbon atoms. Further, a is an integer of 1 to 3,
As understood from the numerical value of a, the unit represented by the general formula (I) always includes _a —Si (OR) _a group, and this group serves as a crosslinkable group in the presence of water. It acts to cause a hydrolysis-polycondensation reaction to form a cured product.

In the present invention, specific examples of the unit represented by the general formula (1) are as follows, although not limited thereto.

[Chemical 7] [In the above formula, Ph represents a phenyl group. ]

In the above-mentioned silane-modified alkylene oxide polymer, the unit represented by the general formula (1) is contained in at least one unit, particularly 2 to 3 units, in one molecule, and such a unit should be introduced. As a result, the curability is improved.
The molecular chain form of the silane-modified alkylene oxide polymer may be linear, branched, cyclic, or a structure in which these are combined, and the molecular weight thereof is not particularly limited, but generally 2, It is preferably in the range of 000 to 12,000.

Further, the silane-modified alkylene oxide polymer includes an alkylene oxide polymer having a molecular chain terminal blocked with an amino group-containing organic group, and the following general formula (2):

[Chemical 8] [Wherein R ^{1 to} R ⁶ and a are as described above] are synthesized by reacting with a silane compound corresponding to the unit of the general formula (1). That is, the amino group at the molecular end of the alkylene oxide polymer reacts with the α, β-unsaturated carboxyl group in the silane compound, and the unit represented by the general formula (1) is an alkylene oxide polymer chain. Will be introduced to. The reaction can be carried out in the absence of a solvent, or can be carried out using a suitable organic solvent such as toluene or xylene. Further, in the reaction, if necessary, HgCl ₂ , Hg (OAc) ₂ , RhCl ₃ , T
It can also be carried out using a catalyst such as 1 (OAc) ₃ . Further, it is desirable to use the silane compound such that the α, β-unsaturated carboxyl group in the silane compound is 1 to 10 times the mole of the amino group. The reaction temperature is 0 to
It is preferably in the range of 150 ° C.

Specific examples of the amino group-containing organic group at the terminal of the molecular chain of the alkylene oxide polymer include, for example, --OCH ₂ CH ₂ NH ₂ , --OCH ₂ CH (CH ₃ ) N.
_{H 2, -OCH 2 CH 2 NH} (CH 3), - OOC-C
_{2 H 4 -CONH-C 2 H} 4 -NH 2, -OOC-C 2
H ₄ can be exemplified _{-CONH-C 2} H 4 -NH ₂ or the like. Two or more of these may be bonded to the molecular end of the alkylene oxide polymer.
Further, the molecular end of the alkylene oxide polymer is blocked with these amino group-containing organic groups by, for example, halogenating the hydroxy group of the hydroxy-containing alkylene oxide polymer using PBr ₅ or the like, and then reacting with ammonia or the like. be able to.

(B) Curing catalyst As the curing catalyst, for example, one similar to that used in a silicone resin composition that cures in the presence of moisture,
For example, a tin-based catalyst, a titanium-based catalyst or the like can be used. Specific examples of the tin catalyst include tin naphthenate, tin caprylate, dibutyltin diacetate, dibutyltin dioctate, dibutyltin dilaurate, dibutyltin dioleate, diphenyltin diacetate, dibityltin oxide, dibutyltin dimethoxide, dibutylbis (tributyltin diacetate. Examples thereof include ethoxysiloxy) tin and dibutyltinbenzylmalate. Specific examples of titanium-based catalysts include titanium such as tetraisopropoxy titanium, tetra-n-butoxy titanium, tetrabis (2-ethylhexoxy) titanium, dipropoxybis (acetylacetona) titanium, titanium isopropoxyoctylene glycol, and the like. Examples thereof include acid esters and titanium chelate compounds. The amount of these curing catalysts used may be a so-called catalytic amount,
For example, it is used in an amount of 0.1 to 10 parts by weight, particularly 0.5 to 5 parts by weight, per 100 parts by weight of the component (A).

In order to enhance the activity of the above curing catalyst,
A basic compound can also be used in combination as an auxiliary agent. Suitable examples of such basic compounds include octylamine,
Amines such as laurylamine, imidazoline, tetrahydropyrimidine, 1,8-diazabicyclo (5,4,4)
0) Examples include guanidyl group-containing silanes or siloxane compounds such as undecene-7 and guanidinepropyltris (trimethylsiloxy) silane, and partial hydrolysates thereof. These are generally 0.1 to 10 parts by weight, especially 0.5 to 100 parts by weight of the component (A).
Used in a proportion of up to 5 parts by weight.

Other Components From the viewpoint of ease of production, preservability when uncured and the like, a silane compound having a hydrolyzable group or a hydrolyzate thereof may be added to the composition of the present invention. . Specific examples thereof include alkoxysilanes such as methyltrimethoxysilane, methyltriethoxysilane, and tetramethoxysilane, methyltri (methylethylketoxime) silane,
Examples thereof include methyltripropenyloxysilane, methyltriacetoxysilane, organosilane in which the methyl group of these silane compounds is changed to a vinyl group, a phenyl group, a trifluoropropyl group, and a hydrolyzate thereof. Particularly preferred are alkoxysilanes such as methyltrimethoxysilane, methyltriethoxysilane and tetramethoxysilane, and partial hydrolysates thereof.

The room temperature curable composition of the present invention may contain various additives conventionally used in this type of composition. For example, a filler may be added, if necessary, for the purpose of reinforcing or increasing the amount. Such fillers include fumed silica, pyrogenic silica,
Finely powdered silica such as precipitated silica, ground silica, fused silica powder; metal oxides such as diatomaceous earth, iron oxide, zinc oxide, titanium oxide, barium oxide, magnesium oxide; metal carbonates such as calcium carbonate, magnesium carbonate, zinc carbonate Examples thereof include salts; metal hydroxides such as cerium hydroxide and aluminum hydroxide; glass fibers, glass wool, carbon black, finely powdered mica, asbestos; and those whose surfaces are hydrophobized with silane or the like. ..
Other additives include thixotropic agents such as polyethylene glycol and its derivatives; pigments; dyes; antioxidants; antioxidants; antistatic agents; flame retardants such as antimony oxide and paraffin chloride; boron nitride, aluminum oxide. Thermal conductivity improver, plasticizer, anti-sagging agent, etc.
Examples thereof include antifouling agents, antiseptics, bactericides, antifungal agents, and adhesiveness-imparting agents. Especially as an adhesion promoter,
Organosilicon compounds having a reactive organic group such as an amino group, an epoxy group and a mercapto group are suitable. Additives other than the components (A) and (B), which are used as necessary, are used in an amount within the range where the object of the present invention of improving curability is not impaired.

Room- Temperature Curable Resin Composition The composition of the present invention is easily prepared by uniformly mixing the above-mentioned components, and is easily cured under room temperature conditions in the presence of moisture to give a rubber elastic body. To form a cured product of. This composition is a building sealant, coating agent,
It is useful as a sealant for electric / electronic parts, potting agent, and surface treatment agent for fibers. In order to apply this composition to a suitable substrate, it may be diluted with a hydrocarbon solvent such as toluene, xylene or petroleum ether, or a solvent such as ketones or esters before use.

[0017]

EXAMPLES Synthesis Example 1 As polypropylene glycol, the end of the molecular chain is -OC.
H ₂ CH ₂ NH ₂ blocked molecular weight 11,000 is used. In a toluene solution of the polypropylene glycol (100 g) dehydrated by heating under reflux, γ-
(Acryloxypropyl) trimethoxysilane (10g)
Was added and reacted at 120 ° C. for 4 hours. After the reaction,
The volatile component in the reaction solution was removed under heating and reduced pressure to obtain a viscous liquid (109 g) having a transparent feeling (yield 99%). The molecular weight of the obtained product was 12,000. In addition, a form in which the acryloyl group of γ- (acryloxypropyl) trimethoxysilane is stoichiometrically added to the amino group at the end of polypropylene glycol by NMR analysis, IR analysis, and Si-OCH ₃ group content measurement analysis by alkali decomposition method. It was confirmed that they are bound together.

Synthesis Example 2 Synthesis Example 1 except that γ- (methacryloxypropyl) trimethoxysilane (11 g) was used in place of γ- (acryloxypropyl) trimethoxysilane (10 g) in Synthesis Example 1. In the same manner, a transparent viscous liquid (109 g) was obtained (yield 99%). The molecular weight of the obtained product was 12,000. Further, by the same analysis as in Synthesis Example 1, it was confirmed that the methacryloyl group of γ- (methacryloxypropyl) trimethoxysilane was bound to the amino group at the end of polypropylene glycol in a stoichiometric manner.

Synthesis Example 3 The end of the molecular chain is blocked with —OCH ₂ CH (CH ₃ ) NH ₂ and the following formula (3) is contained in the main chain.

[Chemical 9] A viscous liquid having a transparent feeling (108 g) was obtained in the same manner as in Synthesis Example 1 except that polypropylene glycol having three units represented by and having a molecular weight of 11,000 was used (yield 98%). The molecular weight of the obtained product is 12,000.
It was 0. Further, by the same analysis as in Synthesis Example 1, γ-
It was confirmed that the acryloyl group of (acryloxypropyl) trimethoxysilane was bound to the amino group at the end of polypropylene glycol in a stoichiometrically added form.

Synthesis Example 4 A transparent viscous liquid (109 g) was obtained in the same manner as in Synthesis Example 2 except that the polypropylene glycol used in Synthesis Example 3 was used (yield 99%). .. The molecular weight of the obtained product was 12,000. Further, by the same analysis as in Synthesis Example 1, it was confirmed that the methacryloyl group of γ- (methacryloxypropyl) trimethoxysilane was bound to the amino group at the end of polypropylene glycol in a stoichiometric manner.

[0021] Synthesis Example 5 molecular chain _{terminals, -OOC-C 6 H 4 -CONH} -C 2 H
_4- NH ₂ group (97%), -COOH group (2%) and-
A polypropylene glycol of 10,000 molecular weight blocked with OH groups (1%) is used. Γ- (Acryloxypropyl) trimethoxysilane (20 g) was added to a toluene solution of the polypropylene glycol (100 g) dehydrated by heating under reflux, and the mixture was reacted at 120 ° C. for 4 hours. After completion of the reaction, volatile components in the reaction solution are removed under heating and reduced pressure to give a transparent viscous liquid (116
g) was obtained (96% yield). The molecular weight of the obtained product was 12,000. Further, by the same analysis as in Synthesis Example 1, it was confirmed that the acryloyl group of γ- (acryloxypropyl) trimethoxysilane was bound to the amino group at the end of polypropylene glycol in a stoichiometric manner.

[0022] Synthesis Example 6 molecular chain _{terminals, -OOC-C 2 H 4 -CONH} -C 2 H
_4- A viscous liquid having a transparent feel was obtained in the same manner as in Synthesis Example 5 except that polypropylene glycol having a molecular weight of 10,000 and blocked with -NH ₂ groups (99%) and -COOH groups (1%) was used. 116 g) was obtained (96% yield). The molecular weight of the obtained product was 12,000. In addition, by the same analysis as in Synthesis Example 1, γ- (acryloxypropyl)
It was confirmed that the acryloyl group of trimethoxysilane was bound to the amino group at the terminal of polypropylene glycol in a stoichiometrically added form.

Examples 1 to 6 Each polymer (800 g) obtained in Synthesis Examples 1 to 6 was mixed with dioctyl phthalate (200 g) and precipitating calcium carbonate (1,000 g) using a triple roll to form a base. The compound was prepared. To this base compound (200 g), methyltrimethoxysilane 5 g dibutyltin dilaurate 1 g γ-aminopropyltriethoxysilane 1 g γ-guanidylpropyltrimethoxysilane 1 g was added and mixed well to form a one-pack type room temperature cure. A sex composition was prepared. This composition was molded into a sheet having a thickness of 2 mm, and then allowed to stand in an atmosphere of 20 ° C. and 60% RH for 7 days, and the physical properties of the obtained cured product were measured according to JIS K-6301 (hardness: , A type hardness spring type tester was used for measurement). Also, using this composition, JIS A-5
758 H-shaped blocks were made. Using glass as an adherend, the composition was cured at 23 ° C. and 55% RH for 7 days, and then at 30 ° C. for 7 days. This cured product was subjected to a tensile tester to measure 50% modulus, maximum tensile strength and maximum elongation. The results are shown in Table 1.
Shown in.

[0024]

[Table 1]

[0025]

EFFECTS OF THE INVENTION According to the present invention, the curability, which is a drawback of the curable composition using the conventional silane-modified alkylene oxide polymer, is effectively improved. The cured product obtained from the composition of the present invention does not show tackiness on the surface and has a high surface strength.

 ─────────────────────────────────────────────────── ─── Continuation of the front page (72) Masatoshi Arai, Masatoshi Arai, Hitomi, Matsuida-cho, Usui-gun, Gunma 10 Shin-Etsu Chemical Co., Ltd. Silicone Electronic Materials Research Laboratory

Claims (2)

[Claims] 1. (A) The following general formula (1): [In the formula, R is a hydrogen atom or a lower alkyl group, R ^{1 to} R ⁴ may be the same or different, and are a hydrogen atom or an unsubstituted or substituted monovalent hydrocarbon group, R ⁵ Which may be the same or different, are unsubstituted or substituted monovalent hydrocarbon groups, R ⁶ is a divalent organic group, and a is an integer of 1 to 3, A room temperature curable composition comprising a silane-modified alkylene oxide polymer having at least one group in one molecule, and (B) a curing catalyst. 2. A cured product obtained by curing the composition according to claim 1.