JPH06104771B2 - Curable composition - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to a curable composition.

[Conventional technology]

Conventional curable compositions include those comprising (1) a functional silicon group-containing polyether, (2) a reaction product of an organotin compound such as dibutyltin oxide, and an ester compound such as dioctylphthalate.

[Problems to be solved by the invention]

 However, in this case, the curing speed is insufficient.

[Means for solving problems]

The present inventors have arrived at the present invention as a result of extensive studies aimed at obtaining a curable composition having an excellent curing rate.

That is, the present invention relates to (1) a reaction product of a polyether urethane prepolymer containing a terminal NCO group and an active hydrogen-containing silane coupling agent, and (2) a polyether compound having an active hydrogen capable of reacting with an NCO group at the terminal. And at least one functional silicon group-containing polyether compound (a) selected from the reaction products of NCO group-containing silane coupling agent and general formula (Wherein R ¹ and R ² are monovalent hydrocarbon groups, R ³ and R ⁴ are aryl groups or substituted aryl groups), and the curing is characterized by containing an organotin compound (b). It is a sex composition.

The organotin compound (b) in the present invention is shown.

In the general formula (1), the monovalent hydrocarbon group of R ₁ and R ₂ is a linear or branched alkyl group having 1 to 20 carbon atoms (eg, methyl, ethyl, hexyl, octyl group), aryl group ( and p-biphenylyl group), alkaryl group (alkenyl group having C _{1 to} C ₂₀ alkyl group such as nonylphenyl group), aralkyl group (benzyl group, phenylethyl group, etc.) and the like.

Of R ₁ and R _2, a C _1-8 alkyl group is preferable.

Examples of the aryl group of R ³ and R ⁴ include a biphenyl group, a phenyl group, and a naphthyl group.

Examples of the substituted aryl group include alkyl-substituted aryl groups (tolyl group, xylyl group, etc.), halogen-substituted aryl groups (chlorophenyl group, etc.), aralkyl-substituted aryl groups. And aryl groups substituted with a functional group containing a hetero atom (such as a nitrophenyl group). General formula (1)
Specific examples of the compound represented by are dibutyltin bis (o
-Phenyl phenoxide, dioctyl tin bis (o-
Phenylphenoxide), diethyltin bis (o-phenylphenoxide), dibutyltin diphenoxide,
Dibutyltin dinaphthooxide, dibutyltin bis (p-benzylphenoxide), dibutyltin ditriloxide, diphenyltin bis (p-nitrophenoxide),
Diphenyl tin bis (p-chlorophenoxide), and the like.

The functional silicon group-containing polyether compound (a) in the present invention includes (1) a reaction product of a terminal NCO group-containing polyether urethane prepolymer and an active hydrogen-containing silane coupling agent; (2) an NCO at the terminal. And a reaction product of a polyether compound having an active hydrogen capable of reacting with a group and an NCO group-containing silane coupling agent; and a mixture of two or more thereof.

In the reaction product of (1), examples of the prepolymer include a prepolymer from a polyether polyol and excess polyisocyanate.

Low molecular weight polyols such as polyether polyols (ethylene glycol, propylene glycol, 1,4-butanediol, glycerin, trimethylolpropane, hexanetriol, sorbitol, sucrose, etc.)
Or alkylene oxide (alkylene oxide having 2 to 4 carbon atoms such as ethylene oxide, propylene oxide, butylene oxide) adduct of amines (alkanolamine, aliphatic polyamine, etc.) (block or random in the case of two or more alkylene oxide adducts) And the ring-opening polymer of the above alkylene oxide, specifically polyethylene glycol, polypropylene glycol and polytetramethylene ether glycol. The average molecular weight of the polyether polyol is usually 62 to 12,000, preferably 200 to 8,000. OH value is usually 1
It is 0 to 1000, preferably 20 to 800.

As polyisocyanate, aliphatic polyisocyanate having 2 to 12 carbon atoms (excluding carbon in NCO group), 4 to 4 carbon atoms
15 alicyclic polyisocyanates, araliphatic polyisocyanates having 8 to 12 carbon atoms, aromatic polyisocyanates having 6 to 20 carbon atoms, and modified products of these polyisocyanates (carbodiimide group, uretdione group, uretoimine group, urea group) , A modified product containing a biuret group and / or an isocyanurate group, etc.) can be used. Such polyisocyanates include ethylene diisocyanate,
Tetramethylene diisocyanate, hexamethylene diisocyanate (HDI), dodecamethylene diisocyanate, 1,6,11-undecane triisocyanate, 2,2,4-trimethylhexane diisocyanate, lysine diisocyanate, 2,6-diisocyanate methyl caproate, bis ( 2-isocyanatoethyl) fumarate, bis (2
-Isocyanatoethyl) carbonate, 2-isocyanatoethyl-2,6-diisocyanate hexanoate;
Isophorone diisocyanate (IPDI), dicyclohexylmethane diisocyanate (hydrogenated MDI), cyclohexylene diisocyanate, methylcyclohexylene diisocyanate (hydrogenated TDI) bis (2-isocyanatoethyl) 4-cyclohexene-1,2-dicarboxylate;
Xylylene diisocyanate, dietine benzene diisocyanate; water-modified HDI, trimer of IPDI, etc .; tolylene diisocyanate (TDI), crude TDI, diphenylmethane diisocyanate (MDI), polyphenylmethane polyisocyanate (PAPI; crude MDI ), Modified MDI (carbodiimide modified, etc.), naphthylene diisocyanate; and mixtures of two or more of these. Of these, aliphatic diisocyanates and alicyclic diisocyanates are preferred from the viewpoint of weather resistance, and particularly preferred are hexamethylene diisocyanate, isophorone diisocyanate and hydrogenated MDI. TDI and MDI are preferred for applications where weatherability is not an issue.

Examples of the active hydrogen-containing silane coupling agent include compounds having an active hydrogen-containing group selected from the group consisting of a hydroxyl group, an amino group and a mercapto group, and a hydrolyzable silyl group selected from the group consisting of an alkoxysilyl group and a halosilyl group. To be

Specific examples include the following compounds.

(1) Silane coupling agent containing amino group: Aminoalkyltrialkoxysilane (γ-aminopropyltrimethoxysilane, γ-aminopropyltriethoxysilane, aminomethyltriethoxysilane, etc.); N
-(Aminoalkyl) aminoalkyltrialkoxysilane [N- (β-aminoethyl) aminomethyltrimethoxysilane, N- (β-aminoethyl) aminomethyltriethoxysilane, N- (β-aminoethyl) -γ- Aminopropyltrimethoxysilane, etc.]; aminoalkyl,
Alkyl dialkoxysilane (aminomethylmethyldiethoxysilane, γ-aminopropylmethyldiethoxysilane, etc.); N- (aminoalkyl) aminoalkylalkyldialkoxysilane [N- (β-aminoethyl)-
γ-aminopropylmethyldimethoxysilane, etc.]; and partial hydrolysates of compounds containing amino group-containing silane coupling agents and hydrolyzable silyl groups, such as amino group-containing silane coupling agents and hydrolyzable silyl groups To a compound containing (ethyl silicate, methyltrimethoxysilane, methyltriethoxysilane, etc.) and water and, if necessary, an acidic or alkaline catalyst,
Reaction products obtained by partial hydrolysis.

(2) Silane coupling agent containing mercapto group: Mercaptoalkylalkoxysilane (γ-mercaptopropyltrimethoxysilane etc.) and the like.

(3) Hydroxyl group-containing silane coupling agent: Amino group-containing silane coupling agent of (1) and a compound containing an epoxy group (ethylene oxide, butylene oxide, epichlorohydrin, epoxidized soybean oil, other Epicoat 828 manufactured by Shell Co., Ltd.) , Epicoat 1001, etc.); epoxy group-containing silane coupling agent [glycidoxyalkyltrialkoxysilane (γ-glycidoxypropyltrimethoxysilane, etc.); glycidoxyalkylalkyldialkoxysilane (γ-glycan) Cidoxypropylmethyldimethoxysilane etc.) and amines such as aliphatic amines (ethylamine, diethylamine, triethylamine, ethylenediamine, hexamethylenediamine, diethylenetriamine, triethylenetetramine, tetraethylene) Pentamine, etc.), aromatic amines (aniline, diphenylamines), alicyclic amines (cyclopentylamine, cyclohexylamine, etc.); alkanolamines (ethanolamines)
Reaction products with etc.

NCO from polyether polyols and polyisocyanates
In obtaining the terminal urethane prepolymer, the equivalent ratio of the NCO group of the polyisocyanate and the active hydrogen-containing group of the polyol and optionally other active hydrogen-containing compound is usually 1: 0.
9 to 1: 0.1 It is preferably 1: 0.8 to 1: 0.4. The average number of terminal NCO groups in the NCO-terminated urethane prepolymer is 2 to 6, preferably 2 to 4, and particularly preferably 2 per molecule.
~ 3 pieces. The average molecular weight of the NCO-terminated urethane prepolymer is usually 200 to 50,000, preferably 500 to 20,000. The free NCO group is usually 0.1 to 42% by weight, preferably 0.
It is 2 to 20% by weight, particularly preferably 0.4 to 8% by weight.
The equivalent weight is usually 100 to 25,000, preferably 210 to 10,000.

The amount of the silane coupling agent having active hydrogen is usually 0.25 to 1.5, preferably 0.8 to 1.2 in molar ratio with respect to the isocyanate group of the NCO-terminated urethane prepolymer. When the silane coupling agent is less than 0.25, the curing rate is slow and the physical properties after curing are weak, and when it exceeds 1.5, further improvement in the physical properties cannot be obtained and the chemical is wasted.

In the polyurethane forming reaction (urethane formation of polyether polyol and polyisocyanate, and reaction of these or prepolymer with silane coupling agent), the reaction temperature is usually 0 to 150 ° C, preferably 25 to 90 ° C. The reaction can be carried out in the presence of an organic solvent which is inert to the isocyanate group, if necessary. Examples of the organic solvent include aromatic hydrocarbons (toluene, xylene, etc.), ketones (methyl ethyl ketone, methyl isobutyl ketone, etc.), esters (ethyl acetate, n-butyl acetate, etc.), and mixtures of two or more thereof. If necessary, a catalyst such as a metal-based catalyst (dibutyltin dilaurate, stannas-2-ethylhexoate, iron-acetylacetonate, etc.) and an amine-based catalyst (triethylenediamine, N-methylmorpholine, etc.) should be used. The amount used is usually 0.005 to 0.2% by weight based on the polyurethane (or its drug). The end point of the reaction can be checked when the isocyanate group cannot be detected by infrared analysis (~ 2,250 cm ^-1 ~).

In the reaction product of (2), the polyether compound having active hydrogen capable of reacting with the NCO group at the terminal is (1)
And a prepolymer from the polyether polyol described in the item (1) and an excess amount of the polyether polyol and the polyisocyanate described in the item (1).

The NCO group-containing silane coupling agent is not particularly limited as long as it has an NCO group and a silyl group. Isocyanate alkylalkoxysilanes such as γ-isocyanatopropyltriethoxysilane, γ-isocyanatopropylmethyldiethoxysilane, γ-isocyanatopropyltrimethoxysilane, and γ-isocyanatopropylmethyldimethoxysilane.

The amount of the NCO group-containing silane coupling agent is usually 0.25 to 1.5, preferably 0.8 to 1.2 in molar ratio with respect to the OH of the polyether polyol.

The conditions and method of the urethane forming reaction (reaction of polyether polyol, NCO group-containing silane coupling agent and polyisocyanate) may be the same as the polyurethane forming reaction of (1).

The average molecular weight of the functional silicon group-containing polyether compound (a) thus obtained is usually 300 to 45,000, preferably 600 to 25,000.

In the composition of the present invention, the weight ratio of the polyether compound (a) and the organic tin (b) is usually 100: 0.01 to 10, preferably
It is 100: 0.05-5. If (b) is less than 0.01, the curing rate will be low, and if it exceeds 10, durability such as weather resistance will be poor.

In addition to (a) and (b), the composition of the present invention may contain a filler, a plasticizer, an additive, an amine compound and the like.

As the filler, ultra-fine powdered calcium carbonate surface-treated with higher fatty acids, clay, talc, titanium oxide,
Examples include silica, aluminum silicate, and carbon black.

Examples of the plasticizer include dioctyl phthalate, dioctyl adipate, and chlorinated paraffin.

As additives, anti-sagging agents (hydrogenated castor oil, colloidal silica, organic bentonite, etc.), anti-aging agents (ultraviolet absorbers, radical chain inhibitors, peroxide decomposers, etc.), adhesion promoters (petroleum resin) , Silane coupling agents, etc.) and colorants are used alone or in combination of two or more.

As the amine compound, triethylenediamine, N, N, N ',
N'tetramethylethylenediamine, octylamine, etc. are used.

The amounts of these other ingredients are usually 10 based on the weight of the composition.
It is at most 00%, preferably at most 600%.

The composition of the present invention includes various inorganic materials (iron, tin plate, galvanized iron, aluminum, zinc steel plate, glass, roof tile, slate, concrete, tile, etc.) and organic materials (wood, paper, cellophane, plastic, organic paint, etc.). It can be applied to a substrate.

As an application method, a usual method, for example, a coating method such as a brush or a fray, and a method of extruding and caulking after filling the cartridge with a cartridge rifle or the like can be mentioned.

The composition of the present invention is usually curable by moisture at a temperature of -30 ° C to + 150 ° C and a humidity of 5 to 100%. The tack-free time of the composition is usually 10 seconds to 3 hours.

〔Example〕

The present invention will be further described below with reference to examples, but the present invention is not limited thereto. The following parts indicate parts by weight.

Example 1 Production of Polyether Compound 4000 parts of polypropylene glycol having an average molecular weight of 4000 and 333 parts of isophorone diisocyanate were reacted in an oil bath at 130 ° C. for 10 hours to obtain a urethane prepolymer having an NCO content of 0.96% by weight.

The urethane prepolymer was cooled to 50 ° C. and 161.4 parts of γ-aminopropylmethyldimethoxysilane was added dropwise to react until the NCO group disappeared to obtain a polyether compound having a functional silicon group. Kneading 100 parts of the polyether compound, 140 parts of surface-treated calcium carbonate, 20 parts of titanium oxide, 40 parts of dioctyl phthalate (DOP) and 1 part of an antioxidant (Irganox 565: Ciba Geigy) in a substantially water-free system. Then, 1 part of dibutyltin bis (o-phenylphenoxide) was added thereto and uniformly kneaded to obtain a curable composition.

The surface tack-free time of this curable composition is 23 ° C 60% RH
It was kept under constant temperature and humidity for 20 minutes.

Example 2 As in Example 1, a polyether compound, a filler, a plasticizer and an additive were added and the mixture was kneaded in a system substantially free of water, and then 1 part of dioctyltin bis (o-phenylphenoxide) was added. The mixture was kneaded uniformly and a curable composition was obtained.

The surface tack-free time of this curable composition is 23 ° C 60% RH
It took 25 minutes under constant temperature and humidity.

Example 3 As in Example 1, a polyether compound, a filler, a plasticizer and an additive were added, and the mixture was kneaded in a system substantially free of water, and then 1 part of dibutyltin diphenoxide was added and uniformly kneaded to obtain a curability. A composition was obtained. The surface tack-free time of this curable composition was 25 minutes under constant temperature and humidity of 23 ° C. and 60% RH.

Comparative Example 1 As in Example 1, a polyether compound, a filler, a plasticizer and an additive were added, and the mixture was kneaded in a system substantially free of water. Then, 1 part of dibutyltin dilaurate was added and uniformly kneaded to obtain a cured composition. Obtained.

The surface tack-free time of this curable composition is 23 ℃, 60% R
It was kept under constant temperature and humidity for 12 hours.

〔The invention's effect〕

The composition of the present invention has an excellent curing rate. In addition, since the composition of the present invention has a good curing balance, it is possible to obtain an elastic body having a good permanent set as well as an internal curability and a thin film curability.

The composition of the present invention is cured by moisture in the air to give a cured product having high tensile strength and elongation, and the cured product has excellent physical properties.
Also, the durability of the cured product (weather resistance, water resistance, heat resistance, etc.)
Is good.

The composition of the present invention having the above-mentioned effects is useful for applications of elastic sealants, paints, cast elastomers and adhesives.

Claims (2)

[Claims] 1. A reaction product of (1) a polyether-based urethane prepolymer containing a terminal NCO group and an active hydrogen-containing silane coupling agent, and (2) a polyether compound having an active hydrogen capable of reacting with an NCO group at the terminal. And at least one functional silicon group-containing polyether compound (a) selected from the reaction products of NCO group-containing silane coupling agent and general formula (In the formula, R1 and R2 are monovalent hydrocarbon groups, and R3 and R4 are aryl groups or substituted aryl groups.) A curable composition containing an organotin compound (b). 2. The composition according to claim 1, wherein the weight ratio of (a) and (b) is 100: 0.01-10.