JPH07331093A - Curable composition - Google Patents

Abstract

PURPOSE:To obtain a curable composition having been dealt with the lack in the adhesion durability in the form of a coating/sealing composition, by incorporating specific silicon compounds in a reactive silyl group-bearing rubber- based organic polymer. CONSTITUTION:This curable composition essentially comprises (A) a rubber- based organic polymer containing in one molecule at least one reactive silyl group (pref. with a molecular weight of 100-50000) (B) a silicon compound having both nitrogen atom and reactive silyl group (e.g. an amino group-bearing alkoxysilane compound) and (C) another silicon compound having both reactive silyl group and at least two epoxy groups (e.g. a condensate of a polyalkoxysilane and an epoxy group-bearing alkoxysilane).

Description

Detailed Description of the Invention

[0001]

FIELD OF THE INVENTION This invention relates to a modified curable composition, and more particularly to a curable composition having remarkably excellent adhesive durability.

[0002]

2. Description of the Related Art Rubber-based organic polymers having at least one reactive silyl group in the molecule have been used in applications such as coating compositions and sealing compositions by taking advantage of the fact that a cured product has rubber elasticity. However, especially for applications such as sealing materials and adhesives, the adhesion durability of the cured product was insufficient depending on the type of base material and the use conditions.

[0003]

SUMMARY OF THE INVENTION An object of the present invention is to solve the above-mentioned drawbacks and to provide a curable composition whose cured product has remarkably excellent adhesion durability.

[0004]

The present invention provides (A) a rubber-based organic polymer containing at least one reactive silyl group in the molecule, and (B) at least one nitrogen atom in the molecule. Curable composition containing as an essential component a silicon compound containing one reactive silyl group, and (C) a silicon compound containing at least two epoxy groups and at least one reactive silyl group in the molecule. It is a thing.

The rubber-based organic polymer used in the present invention and containing at least one reactive silyl group in the molecule is a polyether-based polymer, polyester-based polymer,
A derivative such as a polyisobutylene polymer, a polychloroprene polymer, or a polybutadiene polymer is preferable, and a derivative of a polyether polymer is particularly preferable. Polyethers containing at least one reactive silyl group in the molecule are described in JP-A-3-4782.
5, JP-A-3-72527, JP-A-3-4
It is described in detail in Japanese Patent Laid-Open No. 3449 and Japanese Patent Laid-Open No. 3-79627.

(A) The reactive silyl group contained in the rubber-based organic polymer having at least one reactive silyl group in the molecule means a moisture content such as silanol group and hydrolyzable silyl group. A compound capable of causing a condensation reaction with a curing agent or the like to accelerate the increase in the molecular weight of the organic polymer, which is represented by Chemical Formula 1.

[0007]

## STR1 ## _{^{X 1 3-m -Si (R}} 1 m) - wherein R ¹ is a monovalent hydrocarbon group or halogenated hydrocarbon group, X ¹ is a hydroxyl group, a halogen atom, an alkoxy group, an acyloxy group, an amide A hydrolyzable group such as a group, an amino group, an aminoxy group or a ketoximate group, and m is 0, 1 or 2.

The rubber-based organic polymer having such a reactive silyl group can be obtained by introducing a reactive silyl group into the rubber-based organic polymer, for example, by the following methods (a) and (b). However, the method is not limited to these methods.

(A) A specific organic silicon compound having at least one, preferably only one isocyanate group and at least one hydrolyzable silyl group in the molecule as shown in Chemical formula 2 is added to a rubber-based organic compound. React with the terminal hydroxyl groups of the polymer.

[0010]

Embedded image X ¹ _3-m —Si (R ¹ _m ) —R ² —NCO where R ¹ , X ¹ and m are the same as defined above, R ² is a divalent hydrocarbon group or a halogenated hydrocarbon group. .

The following compounds can be shown as specific organic silicon compounds. (C ₂ H ₅ O) ₃ Si (CH
₂ ) ₃ NCO, (CH ₃ O) ₃ Si (CH ₂ ) ₃ NC
_{O, (CH 3 O) 2} (CH 3) Si (CH 2) 3 NC
_{O, (CH 3 O) 3} SiNCO, (CH 3 O) 2 Si
(NCO) ₂ .

(B) A terminal unsaturated group obtained by reacting a terminal unsaturated group-containing isocyanate compound or a terminal unsaturated group-containing halogen compound with a terminal hydroxyl group of a rubber-based organic polymer and a hydrosilicone represented by Chemical Formula 3 Compound
React in the presence of a Group VIII transition metal. Alternatively, the terminal unsaturated group of the polyether compound derived from the initiator is reacted with the hydrosilicon compound represented by Chemical formula 3 in the presence of a Group VIII transition metal.

[0013]

## STR00003 ## X ¹ _3-m --Si (R ¹ _m ) H In the formula, R ¹ , X ¹ and m are the same as defined above.

Specific examples include allyl isocyanate as the terminal unsaturated group-containing isocyanate compound and allyl chloride as the terminal unsaturated group-containing halogen compound.
In addition to the above methods, the methods described in JP-A-5-194678 and the like can be mentioned.

The rubber-based organic polymer (A) used in the present invention thus obtained has a molecular weight of 100 to 50,000.
Is preferred, and 4000-30000 is particularly preferred.

In the present invention, the silicon compound (B) containing at least one nitrogen atom and at least one reactive silyl group in the molecule is an amino group-containing alkoxysilane compound, an epoxy group-containing alkoxysilane compound or Examples thereof include a reaction product of a methacryloxysilane compound and an amino group-containing alkoxysilane compound, or an alkoxysilane compound having a group capable of forming an amino group by moisture. Specific examples include the following compounds.

Amino group-containing alkoxysilane compound; 3
-Aminopropyltrimethoxysilane, 3- (2-aminoethyl) aminopropyltrimethoxysilane, 3-
Examples include (2-aminoethyl) aminopropylmethyldimethoxysilane and 1,4-di (triethoxysilylpropyl) ethylenediamine.

Reaction product of the above-mentioned amino group-containing alkoxysilane and epoxy group-containing alkoxysilane compound; as the epoxy group-containing alkoxysilane compound, 3-glycidoxypropyltrimethoxysilane, 3-glycidoxypropylmethyldimethoxysilane, 3 -Glycidoxypropyltriethoxysilane, 3-glycidoxypropylmethyldimethoxysilane, 3-glycidoxymethylisopropenyloxysilane, 2- (3,4-epoxycyclohexyl) ethyltrimethoxysilane, 2- (3,3 4-
Epoxycyclohexyl) ethylmethyltrimethoxysilane, 5,6-epoxyhexyltrimethoxysilane,
9,10-Epoxyoctyltrimethoxysilane, N-
Examples thereof include glycidyl-N, N-di (trimethoxysilylpropyl) amine and N-glycidyl-N, N-di (methyldimethoxysilylpropyl) amine.

Reaction product of the above-mentioned amino group-containing alkoxysilane and methacryloxysilane compound; as the methacryloxysilane compound, 3-methacryloxypropyltrimethoxysilane, 3-methacryloxypropylmethyldimethoxysilane, 3-methacryloxypropyltriethoxy. Examples thereof include silane, 11-methacryloxyundecyltrimethoxysilane, and 3- (2-methacryloxyethyl) oxypropyltrimethoxysilane.

Alkoxysilane compounds having a functional group capable of generating an amino group by moisture; examples of the functional group capable of generating an amino group by moisture include ketimine and silazane. Examples of such compounds include compounds represented by the following chemical formula 4, chemical formula 5, chemical formula 6, and chemical formula 7.

[0021]

R ³ R ⁴ C = N—R ⁵ —SiX ² _3-n (R ⁶ ) _{n In the} formula, R ³ , R ⁴ and R ⁶ are monovalent hydrocarbon groups or halogenated hydrocarbon groups, R ⁵ is a divalent organic group, X ² is a hydrolyzable group such as a hydroxyl group, a halogen atom, an alkoxy group, an acyloxy group, an amide group, an amino group, an aminoxy group or a ketoximate group, and n is 0, 1 or 2.

[0022]

(R ⁷ R ⁸ N) (R ⁹ R ¹⁰ N) C = N-R ^11-
SiX ² _3-n (R ¹² ) _{n In the} formula, R ⁷ , R ⁸ , R ⁹ , R ¹⁰ and R ¹² are monovalent hydrocarbon groups or halogenated hydrocarbon groups, R ¹¹ is a divalent organic group, X
² and n are the same as above.

[0023]

Embedded image R ¹³ R ¹⁴ C═N—R ¹⁵ —N (R ¹⁶ SiX
² _3-n (R ¹⁷ ) _n ) -R ¹⁸ -N = CR ¹⁹ R ^{20 In the} formula, (R ¹³ , R ¹⁴ , R ¹⁷ , R ¹⁹ , and R ²⁰ are monovalent hydrocarbon groups or halogen-valent hydrocarbon groups. , R ¹⁵ , R ¹⁶ and R ¹⁸ are 2
The valent organic group, X ² and n are the same as above.

[0024]

Embedded image R ²¹ R ²² R ²³ Si (R ²⁴ R ²⁵ R ²⁶ Si) N-R
^27- SiX ² _3-n (R ²⁸ ) _{n In the} formula, R ²¹ , R ²² , R ²³ , R ²⁴ , R ²⁵ , R ²⁶ and R ²⁸ are 1
Valent hydrocarbon group or halogenated hydrocarbon group, R ²⁷ is 2
The valent organic group, X ² and n are the same as above.

The compound represented by the chemical formula 4 is, for example, a ketone represented by R ³ R ⁴ C = O and H ₂ N-R ⁵
It can be produced by a reaction with an amino group-containing alkoxysilane compound represented by —SiX ² _3-n (R ⁶ ) _n . Also,
Epoxy group-containing silane compounds such as 3-glycidoxypropyltrimethoxysilane, halogen atom-containing silane compounds such as chloropropyltrimethoxysilane, or isocyanate group-containing silane compounds such as isocyanatepropyltrimethoxysilane, and R ³ R ⁴ C = NH
It can be similarly produced by a reaction with a ketimine represented by

The compound represented by the chemical formula 5 is, for example, a ketone represented by (R ⁷ R ⁸ N) (R ⁹ R ¹⁰ N) C═O and H ₂ NR ¹¹ -SiX ² _3-n ( It can be produced by a reaction with an amino group-containing alkoxysilane compound represented by R ¹² ) _n . Further, an epoxy group-containing silane compound such as 3-glycidoxypropyltrimethoxysilane, a halogen atom-containing silane compound such as chloropropyltrimethoxysilane, or an isocyanate group-containing silane compound such as isocyanatepropyltrimethoxysilane (R ⁷ It can be similarly produced by a reaction with a guanidine compound represented by R ⁸ N) (R ⁹ R ¹⁰ N) C═NH.

The compound represented by Chemical formula 6 is, for example, an epoxy group-containing silane compound such as 3-glycidoxypropyltrimethoxysilane, a halogen atom-containing silane compound such as chloropropyltrimethoxysilane, or isocyanate propyltrimethoxysilane. Isocyanate group-containing silane compounds such as methoxysilane and R ¹³ R ¹⁴ C =
May be prepared by the reaction of N-R ¹⁵ -NH-R ¹⁸ amino group-containing ketimines represented by -N = CR ¹⁹ R ^20.

The silicon compound containing at least two epoxy groups and at least one reactive silyl group in the molecule (C) used in the present invention is a polyalkoxysilane or polyalkoxypolysiloxane compound and an epoxy group-containing alkoxy. Condensation reaction product with a silane compound,
Alternatively, a reaction product of a polyvalent amino group-containing alkoxysilane compound and a polyvalent epoxy group-containing compound can be used. In these cases, compounds having various structures or molecular weights can be obtained by adjusting the charging ratio of reaction raw materials and reaction conditions. Finally, at least two epoxy groups and at least one reaction in the molecule. A silyl group is included.

Examples of polyalkoxysilanes include tetramethoxysilane, tetraethoxysilane, methyldimethoxysilane, and methyldiethoxysilane.

Examples of the polyalkoxypolysiloxane compound include the reactive silyl group-containing polysiloxane represented by Chemical formula 8.

[0031]

Embedded image (R ²⁹ ) _3-t X ³ _t SiO- (SiX ³ _p (R ³⁰ ) _{2-p
^{O) q SiX 3 t (R}} 31) 3-t wherein R ^29, R ^30, R ³¹ represents a monovalent hydrocarbon group or halogenated hydrocarbon group. R ^{30 s} may all be the same or different. X ³ is a halogen atom, an alkoxy group, an acyloxy group, an amido group, an amino group, an aminoxy group, or a hydrolyzable group such as a ketoximate group, X ³
May all be the same or different. t is 0,
1, 2 or 3, p is 0, 1 or 2, q is 0 or 1
Greater than or equal to an integer. However, 2t + qp is 1 or more.

The compounds exemplified above can be used as the epoxy group-containing alkoxysilane compound.

As an example of a condensation reaction product of a reactive silyl group-containing polysiloxane and 3-glycidoxypropyltrimethoxysilane, a compound in which X ³ in Chemical Formula 8 is Chemical Formula 9 can be exemplified. .

[0034]

[Chemical 9]

Here, the ratio of the component (B) to the component (A) used is (A) / (B) = 100 / 0.0 by weight.
The range of 1 to 100/20 is preferable. The ratio of the component (C) to the component (A) is (A) / weight ratio.
The range of (C) = 100 / 0.01 to 100/20 is preferable.

In the curable composition of the present invention, a curing accelerating catalyst that accelerates the curing reaction of the reactive silyl group may be used in order to accelerate the curing with moisture. As the curing accelerating catalyst, a metal salt of a carboxylic acid such as alkyl titanate, organosilicon titanate, bismuth tris-2-ethylhexoate, tin octylate and dibutyltin dilaurate: dibutylamine-2-ethylhexanoate. Amine salts such as xoates, etc., as well as other acidic and basic catalysts may be used. Further, a dehydrating agent may be added to the curable composition of the present invention in order to further improve storage stability. As the dehydrating agent, a hydrolyzable organic silicon compound such as an alkyl orthoformate: vinyltrimethoxysilane or tetraethylsilicate: a hydrolyzable organic titanium compound may be used.

The curable composition of the present invention may further contain a filler, a plasticizer and the like, if necessary. Known fillers can be used as the filler, and specifically, fillers such as fumed silica, precipitated silica, silicic acid anhydride, hydrous silicic acid and carbon black, calcium carbonate, magnesium carbonate, diatomaceous earth, calcined Clay, clay, talc, titanium oxide, bentonite, organic bentonite, ferric oxide, zinc oxide, activated zinc white, filler such as hydrogenated castor oil and shirasu balloon, fibrous filler such as asbestos, glass fiber and filament Can be used.

As the plasticizer, known plasticizers can be used, and specifically, phthalic acid esters such as dioctyl phthalate, dibutyl phthalate and butylbenzyl phthalate;
Aliphatic carboxylic acid esters such as dioctyl adipate, diisodecyl succinate, dibutyl sebacate, butyl oleate; glycol esters such as pentaerythritol ester; phosphoric acid esters such as trioctyl phosphate, tricresyl phosphate; epoxidized soybean oil , Epoxy plasticizers such as benzyl epoxy stearate; chlorinated paraffins and the like can be used alone or as a mixture of two or more kinds.

The curable composition of the present invention may further contain various known additives. As the additive, an adhesiveness-imparting agent such as epoxysilane, mercaptosilane and epoxy resin, a pigment, various antiaging agents, an ultraviolet absorber and the like can be used.

The curable composition of the present invention cures at room temperature in the presence of moisture and can be used especially for elastic sealants and adhesives.

[Production Example 1] Propylene oxide was polymerized with a zinc hexacyanocobaltate catalyst using a diethylene glycol-propylene oxide adduct having a molecular weight of 1000 as an initiator to obtain polyoxypropylene diol having an average molecular weight of 10,000. Isocyanatopropylmethyldimethoxysilane was added to this to undergo a urethane reaction to convert hydroxyl groups at both ends into methyldimethoxysilyl groups, and an organic polymer having an average of 1.2 hydrolyzable silicon groups per molecule (A1). Got

[Production Example 2] Propylene oxide was polymerized with a zinc hexacyanocobaltate catalyst using a diethylene glycol-propylene oxide adduct having a molecular weight of 1000 as an initiator to obtain polyoxypropylene diol having an average molecular weight of 17,000, and the terminal hydroxyl group was allyloxy. After conversion into a group, methyldimethoxysilane was subjected to an addition reaction using chloroplatinic acid as a catalyst to obtain an organic polymer (A2) having an average of 1.6 hydrolyzable silicon groups per molecule.

[Production Example 3] Propylene oxide was polymerized with a zinc hexacyanocobaltate catalyst using a glycerin-propylene oxide adduct having a molecular weight of 1000 as an initiator to obtain polyoxypropylene triol having an average molecular weight of 15,000, and the terminal hydroxyl group was allyloxy. After conversion into a group, methyldimethoxysilane was subjected to an addition reaction using chloroplatinic acid as a catalyst to obtain an organic polymer (A3) having an average of 1.8 hydrolyzable silicon groups per molecule.

[Production Example 4] Polyoxypropylene diol having an average molecular weight of 4000 was reacted with bromochloromethane, and the terminal hydroxyl group was reacted with allyl chloride.
After the terminal allyloxy group was formed, methyldimethoxysilane was subjected to an addition reaction using chloroplatinic acid as a catalyst to obtain an organic polymer (A4). The average molecular weight of this organic polymer in terms of polyoxypropylene diol was 11,000.

[Preparation Example 5] 222.4 g (1.0%) of 3- (2-aminoethyl) aminopropyltrimethoxysilane
Glycidoxypropyltrimethoxysilane (118.2 g (0.5 mol)) was added to the reaction mixture, and the mixture was stirred in a glass reactor at 50 ° C. for 7 days under a N ₂ gas flow to carry out the reaction to carry out the reaction to obtain a nitrogen atom-containing silicon compound (B1). ) Got.

Production Example 6 222.4 g (1.0) of 3- (2-aminoethyl) aminopropyltrimethoxysilane
124.2 g (0.5 mol) of methacryloxypropyltrimethoxysilane was added to (mol mol), and the reaction was carried out by stirring in a glass reactor at 50 ° C. for 7 days under N ₂ gas flow and the nitrogen atom-containing silicon compound (B2). Got

[Production Example 7] 206.4 g of 3- (2-aminoethyl) aminopropylmethyldimethoxysilane
3-glycidoxypropyltrimethoxysilane (118.2 g, 0.5 mol) was added to (1.0 mol), and the mixture was stirred in a glass reactor at 50 ° C. for 7 days under N ₂ gas flow to carry out the reaction, and nitrogen was added. An atom-containing silicon compound (B3) was obtained.

[Production Example 8] A nitrogen atom-containing silicon compound (B4) was obtained by reacting 1,1,3,3-tetramethylguanidine and 3-glycidoxypropyltrimethoxysilane in an equimolar reaction.

[Production Example 9] 2,4,12,14-tetramethyl-5,8,11-triaza-4,11-pentadecadiene and 3-glycidoxypropyltrimethoxysilane were reacted in equimolar amounts. Silicon compound containing nitrogen atom (B
5) was obtained.

[Production Example 10] 2 mol of 3-glycidoxypropyltrimethoxysilane was subjected to a condensation reaction with 1 mol of tetramethoxysilane to obtain an epoxy group-containing silicon compound (C1) having two epoxy groups in the molecule. It was

[Production Example 11] 1 mol of 3-glycidoxypropyltrimethoxysilane was subjected to a condensation reaction with 1 mol of polymethoxypolysiloxane having a molecular weight of 500 (condensation product of tetramethoxysilane of 4 mol) to give an epoxy resin having M _w of 10,000. A group-containing silicon compound C2 was obtained. The epoxy group content of this compound was 1.6 meq / g and the methoxy group content was 12.5 meq / g.

[Examples and Comparative Examples] With respect to 100 parts by weight of the organic polymers (A1 to A4) shown in Production Examples 1 to 4,
100 parts by weight of calcium carbonate, 10 parts by weight of titanium oxide,
3 parts by weight of vinyltrimethoxysilane, 5 parts by weight of hydrogenated castor oil, 1 part by weight of a phenolic antioxidant, 1.0 part by weight of a nitrogen atom-containing silicon compound in Table 1, and an epoxy group-containing silicon compound of Table 2. 5 parts by weight and 1 part by weight of dibutyltin dilaurate were kneaded under the condition that moisture was not contained to obtain a room temperature curable composition.

These compositions were stable for a long time under a sealed condition, and when they were exposed to moisture, they started to cure immediately and changed into good rubber elastic bodies. The adhesiveness of each room temperature curable composition is shown in Tables 1 and 2.

Tensile shear strength (unit: kg / cm ² ) is J
The tensile shear strength was measured with an aluminum plate in accordance with IS-K6850. The initial adhesiveness is an evaluation of the tensile shear strength and the adhesive state after curing at 50 ° C and 60% humidity for 7 days, and the water-resistant adhesiveness is after curing at 50 ° C and 60% humidity for 7 days, then it is exposed to water at 20 ° C for 14 days. Immediately after immersion for a day, the tensile shear strength and the adhesion state were evaluated, and the adhesion state was evaluated by CF.
(Cohesive failure), AF (interfacial peeling).

[0055]

[Table 1]

[0056]

[Table 2]

[0057]

The curable composition of the present invention has the effect of giving a cured product having excellent adhesion durability.

Claims (4)

[Claims] 1. A rubber-based organic polymer containing (A) at least one reactive silyl group in the molecule, and (B) at least one nitrogen atom and at least one reactive silyl group in the molecule. A curable composition containing as an essential component a contained silicon compound and (C) a silicon compound containing at least two epoxy groups and at least one reactive silyl group in the molecule. 2. The curable composition according to claim 1, wherein the rubber-based organic polymer (A) having at least one reactive silyl group in the molecule is a derivative of a polyether-based polymer. 3. A silicon compound having at least one nitrogen atom and at least one reactive silyl group in the molecule (B) is an amino group-containing alkoxysilane compound, an epoxy group-containing alkoxysilane compound or methacryloxysilane. A reaction product of a compound and an amino group-containing alkoxysilane compound, or an alkoxysilane compound having a group capable of forming an amino group by moisture.
Or the curable composition of 2. 4. (C) A silicon compound containing at least two epoxy groups and at least one reactive silyl group in the molecule is a polyalkoxysilane or polyalkoxypolysiloxane compound and an epoxy group-containing alkoxysilane compound. The curable composition according to claim 1, which is a condensation reaction product of