JPH11279253A - Curing composition - Google Patents

Abstract

PROBLEM TO BE SOLVED: To obtain a curing composition excellent in stain resistance and not causing deterioration in properties of the composition with time. SOLUTION: This polyurethane-based curing composition contains a polyether compound A of the formula Z- (R<1> O)n R<2> }m [(m) is 1-6; (n) is 4-150; Z is a residue of alcohols, phenols or amines, having a valence of (m); R<1> is a 1-24C alkylene or a substituted alkylene; R<2> is a monovalent hydrocarbon group] as a plasticizer, doesn't cause the bleedout of the plasticizer, and is improved in stain resistance in the surface of a cured product and is improved in resistance to deterioration in properties with time.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

[0001] The present invention relates to a polyurethane-based curable composition. More specifically, the present invention relates to a polyurethane-based curable composition in which the dissolution (bleed-out) of a plasticizer from a cured product is small, the stain resistance of the cured product, and the deterioration of physical properties over time are improved.

[0002]

2. Description of the Related Art Polyurethane-based curable compositions are cured at room temperature, and the cured products have good rubber elasticity.
It is used as a waterproofing material, flooring material, sealing material and the like. Such a polyurethane-based curable composition usually contains a plasticizer for the purpose of imparting flexibility.
Conventionally, phthalic acid esters such as dioctyl phthalate (DOP) and dibutyl phthalate, fatty acid esters such as dioctyl adipate, and chlorinated paraffins have been used as this type of plasticizer.

[0003]

However, when a polyurethane-based curable composition using these low-molecular plasticizers is used, for example, as a sealing material, the plasticizer dissolves on the surface of the cured product, that is, bleeds out. Is inevitable,
Stickiness occurs on the surface of the cured product, causing dirt due to adhesion of dust and the like. In addition, when a coating is applied to the surface of the cured product, the bleed-out plasticizer softens and peels off the coating film, thereby significantly impairing the appearance of the cured product. Furthermore, the plasticizer bleeds out to lose the flexibility of the cured product, and there is a problem that cracks are generated particularly when used in applications where the cured product is exposed to sunlight outdoors. For the purpose of improving the problems caused by the bleed-out of these plasticizers, urethane sealant compositions using a polyester plasticizer synthesized from a polyether polyol and a dibasic acid have been proposed (Japanese Patent Publication No. 6-23379). No.). However, this is inferior in compatibility between the polyurethane as the main component and the plasticizer, cannot suppress the bleed-out of the plasticizer, and does not have sufficient stain resistance and flexibility.

[0004]

Means for Solving the Problems The inventors of the present invention have conducted intensive studies to solve the above-mentioned problems, and as a result, the use of a polyether compound having a specific chemical structure as a plasticizer in a polyurethane-based curable composition has led to curing. It has been found that the bleed-out of the plasticizer from the product does not occur, and the stain resistance of the cured product and the decrease in flexibility over time are improved. That is, the present invention is a polyurethane-based curable composition containing a polyether compound (A) represented by the following general formula (1) as a plasticizer. Z-｛(R ¹ O) _n R ² ｝ _m (1) (where m is a number of 1 to 6, n is a number of 4 to 150, and Z is m
R ¹ represents an alkylene group or substituted alkylene group having 1 to 24 carbon atoms, and R ² represents a monovalent hydrocarbon group. )

[0005]

DESCRIPTION OF THE PREFERRED EMBODIMENTS In the general formula (1) representing the polyether compound (A) used in the present invention, Z represents an m-valent (m is a number of 1 to 6) alcohols, phenols or amines. Residue.

As these alcohols, for example,
Monohydric alcohols such as methanol, butanol, lauryl alcohol, isopropyl alcohol, cyclohexanol, allyl alcohol, oleyl alcohol, and benzyl alcohol; ethylene glycol, propylene glycol, 1,3-butylene glycol, 1,4-butanediol, 1,6 -Hexanediol, 3-methylpentanediol, diethylene glycol, neopentyl glycol, 1,4-bis (hydroxymethyl) cyclohexane, 1,4-bis (hydroxyethyl) benzene,
2,2-bis (4,4'-hydroxycyclohexyl)
Dihydric alcohols such as propane; trihydric alcohols such as glycerin and trimethylolpropane; pentaerythritol, diglycerin, α-methylglucoside, sorbitol, xylit, mannitol, dipentaerythritol, gluco- 4-6 such as sugar, fructose and sucrose
Valent alcohol.

Examples of the phenols include monohydric phenols such as phenol and cresol; polyphenols such as pyrogallol, catechol and hydroquinone; and bisphenols such as bisphenol A, bisphenol F and bisphenol S.

As amines, monoamines such as alkylamines having 1 to 20 carbon atoms (such as butylamine) and aniline; aliphatic polyamines such as ethylenediamine, trimethylenediamine and hexamethylenediamine;
Heterocyclic polyamines such as piperazine and N-aminoethylpiperazine; alicyclic polyamines such as dicyclohexylmethanediamine and isophoronediamine; phenylenediamine, tolylenediamine, diethyltolylenediamine, xylylenediamine, diphenylmethanediamine;
Aromatic polyamines such as diphenyletherdiamine and polyphenylmethanepolyamine; and monoethanolamine, diethanolamine, triethanolamine,
And alkanolamines such as triisopropanolamine.

Of these, preferred are monohydric alcohols and dihydric phenols, more preferably monohydric alcohols having 1 to 6 carbon atoms or bisphenol A.

In the general formula (1) representing the polyether compound (A) used in the present invention, R ¹ has 1 to ¹ carbon atoms.
24 alkylene groups or substituted alkylene groups. These alkylene groups or substituted alkylene groups are usually formed by adding a cyclic ether compound to alcohols, phenols or amines. Examples of the cyclic ether compound for deriving R ¹ include ethylene oxide (EO), propylene oxide (PO), 1,2-
Alternatively, 2,3-butylene oxide, tetrahydrofuran (THF), styrene oxide, α-olefin oxide, epichlorohydrin, 1,3-dioxolan, allyl glycidyl ether, butyl glycidyl ether and the like can be mentioned. These cyclic ether compounds may be used alone or in combination of two or more kinds. In the latter case, block addition, random addition or a mixed system of both may be used. Among these cyclic ether compounds, preferred are PO alone, THF alone, a combination of PO and EO, PO
And / or a combination of EO and THF (in the case of a combination, random, block or a mixture of both), particularly preferably PO alone.

The addition of the cyclic ether compound to the alcohols, phenols or amines can be carried out by a conventional method, without a catalyst or in the presence of a catalyst (alkali catalyst, amine catalyst, acidic catalyst) (particularly AO). (In the latter stage of the addition) in normal or elevated pressure in one or more stages.

In the general formula (1) representing the polyether compound (A) used in the present invention, R ² is a monovalent hydrocarbon group. Examples of these monovalent hydrocarbon groups include alkyl groups such as methyl, ethyl, n-butyl, lauryl and isopropyl; alkenyl groups such as vinyl, allyl and oleyl; and aryl groups such as phenyl and benzyl. Preferred among these monovalent hydrocarbon groups are alkyl groups, and particularly preferred are monovalent alkyl groups having 1 to 4 carbon atoms such as methyl and butyl.

In the general formula (1) representing the polyether compound (A) used in the present invention, m is usually from 1 to 6
Is the number of Preferably m is 1 to 5, particularly preferably 1
~ 3. When m exceeds 6, the viscosity of the plasticizer increases, and the workability during handling deteriorates.

In the general formula (1) representing the polyether compound (A) used in the present invention, n is usually 4 to 1
50, preferably 10 to 100, particularly preferably 15 to
70. When n is less than 4, the bleed out of the plasticizer becomes large, and the stain resistance and durability of the cured product become insufficient. If n exceeds 150, the viscosity of the plasticizer increases, and the workability during handling deteriorates.

The number average molecular weight of the polyether compound (A) used in the present invention is generally from 500 to 8,000, preferably from 1,000 to 6,000, particularly preferably from 2,000 to 2,000.
4000. If the number average molecular weight is less than 500, the bleed out of the plasticizer from the cured product tends to increase, and if it exceeds 8000, the viscosity of the curable composition increases, and the workability during handling tends to deteriorate. .

The polyurethane-based curable composition of the present invention comprises 1
Or two-pack type. The term "one-pack type" means that the terminal NCO group of the urethane prepolymer reacts with the moisture in the atmosphere after application and cures, and the term "two-pack type" means that the main agent containing the prepolymer having the terminal NCO and polyols during application. And curing by mixing with a curing agent containing
These curable compositions usually have a terminal NC in the case of a one-pack type.
An O-containing prepolymer, a plasticizer represented by the general formula (1), and a curing acceleration catalyst;
It comprises a main agent containing a prepolymer as a main component, a curing agent, a plasticizer represented by the general formula (1), and a curing agent mainly containing a curing acceleration catalyst. In the case of a two-pack type, a plasticizer represented by the general formula (1) may be blended with the main component.

The prepolymer containing terminal NCO used in the present invention is usually obtained by reacting a polyol with an excess of polyisocyanate. Examples of these polyols include active hydrogens such as ethylene glycol, propylene glycol, diethylene glycol, dipropylene glycol, 1,3-butanediol, bisphenol A, hydrogenated bisphenol A, glycerin, trimethylolpropane, pentaerythritol, and sorbitol. Compounds obtained by adding one or more of ethylene oxide, propylene oxide, butylene oxide, tetrahydrofuran, or the like to the compound (the polymerization mode when two or more are added may be random or block). If necessary, ethylene glycol, propylene glycol, diethylene glycol,
Polyhydric alcohols such as dipropylene glycol, 1,3-butanediol, hydrogenated bisphenol A, glycerin, trimethylolpropane, pentaerythritol and sorbitol may be added. These polyols are 2
It is also used as a curing agent in the case of a liquid type.

As the above-mentioned polyisocyanate, those conventionally used for producing polyurethane can be used. Such polyisocyanates include carbon numbers (NC
6 to 20 aromatic polyisocyanate, C2 to C18 aliphatic polyisocyanate, C4 to C15 alicyclic polyisocyanate,
C8 to C15 araliphatic polyisocyanates and modified products of these polyisocyanates (urethane group, carbodiimide group, allophanate group, urea group, buret group, uretdione group, uretoimine group, isocyanurate group, oxazolidone group-containing modification) And mixtures of two or more of these.

Specific examples of the aromatic polyisocyanate include 1,3- and / or 1,4-phenylene diisocyanate, 2,4- and / or 2,6-tolylene diisocyanate (TDI), crude TDI, ,
4'- and / or 4,4'-diphenylmethane diisocyanate (MDI), 4,4'-diisocyanatobiphenyl, 3,3'-dimethyl-4,4'-diisocyanatobiphenyl, 3,3'-dimethyl -4,4'-diisocyanatodiphenylmethane, crude MDI [crude diaminophenylmethane [condensation product of formaldehyde and aromatic amine (aniline) or a mixture thereof; diaminodiphenylmethane and a small amount (for example, 5 to 20% by weight)]
A mixture with a triamine or higher polyamine]: polyallyl polyisocyanate (PAPI)],
1,5-naphthylene diisocyanate, 4,4 ', 4 "
-Triphenylmethane triisocyanate, m- and p-isocyanatophenylsulfonyl isocyanate.

Specific examples of the aliphatic polyisocyanate include ethylene diisocyanate, tetramethylene diisocyanate, hexamethylene diisocyanate (H
DI), dodecamethylene diisocyanate, 1,6,1
1-undecane triisocyanate, 2,2,4-trimethylhexamethylene diisocyanate, lysine diisocyanate, 2,6-diisocyanatomethyl caproate, bis (2-isocyanatoethyl) fumarate, bis (2-isocyanatoethyl) carbonate And aliphatic polyisocyanates such as 2-isocyanatoethyl-2,6-diisocyanatohexanoate.

Specific examples of the alicyclic polyisocyanate include isophorone diisocyanate (IPDI), dicyclohexylmethane-4,4'-diisocyanate (hydrogenated MDI), cyclohexylene diisocyanate,
Methylcyclohexylene diisocyanate (hydrogenated TD
I), bis (2-isocyanatoethyl) -4-cyclohexene-1,2-dicarboxylate, 2,5- and / or 2,6-norbornane diisocyanate.

Specific examples of the araliphatic polyisocyanate include m- and / or p-xylylene diisocyanate (XDI), α, α, α ′, α′-tetramethylxylylene diisocyanate (TMXDI). Can be

The modified polyisocyanate includes modified MDI (urethane-modified MDI, carbodiimide-modified MDI, trihydrocarbyl phosphate-modified MD).
I), urethane-modified TDI, biuret-modified HDI, isocyanurate-modified HDI, isocyanurate-modified IP
Modified product of polyisocyanate such as DI and a mixture of two or more of these [for example, combined use of modified MDI and urethane-modified TDI (isocyanate-containing prepolymer)]
Is included.

In the curable composition of the present invention, the plasticizer represented by the general formula (1) is usually used in an amount of 15 to 100 parts by weight (hereinafter referred to as “parts by weight”) based on the NCO-containing prepolymer.
200 parts, preferably 50 to 150 parts, are used. If the amount of the plasticizer is less than 15 parts, the flexibility of the cured product is not sufficient, and if it exceeds 200 parts, the physical properties of the cured product are deteriorated.
Further, the amounts of other components used in the curable composition of the present invention may be appropriately set according to the purpose.

The plasticizer used in the present invention is a polyether compound represented by the general formula (1), but a plasticizer conventionally used may be used in combination as long as the effects of the present invention are not impaired. . Examples of these plasticizers include ester plasticizers [dibutyl phthalate, dioctyl phthalate, dioctyl adipate, polyethylene glycol (molecular weight: 200) diadipate, etc.]; tar plasticizers [tar, asphalt, etc.]; petroleum resin plasticizers Is mentioned.

As the curing accelerating catalyst used in the present invention, a metal catalyst such as a tin catalyst [trimethyltin laurate, trimethyltin hydroxide, dimethyltin dilaurate, dibutyltin diacetate, dibutyltin dilaurate, stannasoctoate, dibutyl Tin maleate, etc.], lead-based catalysts [lead oleate, 2-ethylhexanoate, lead naphthenate, lead octenoate, etc.], other metal catalysts [metal salts of naphthenate such as cobalt naphthenate, phenylmercuric propionic acid] Salt, etc.];
And amine catalysts such as triethylenediamine, tetramethylethylenediamine, tetramethylhexylenediamine, diazabicycloalkenes [1,8-diazabicyclo [5,4,0] undecene-7 [DBU (manufactured by San Apro, registered trademark)]) A dialkylaminoalkylamine [dimethylaminoethylamine, dimethylaminopropylamine, diethylaminopropylamine, dibutylaminoethylamine, dimethylaminooctylamine, dipropylaminopropylamine, etc.] or a heterocyclic aminoalkylamine [2- (1 -Aziridinyl) ethylamine, 4- (1-piperidinyl)-
2-hexylamine, etc.] and N-methylmorpholine, N-ethylmorpholine, triethylamine, diethylethanolamine, dimethylethanolamine, and the like; and a combination of two or more thereof. Is mentioned.

In the present invention, if necessary, various additives such as fillers, antioxidants, ultraviolet absorbers, stabilizers such as antioxidants, solvents, coloring agents (dyes and pigments), flame retardants and bactericides are used. Can be blended. Examples of fillers include
Clay, calcium carbonate, barium sulfate, alumina, silica, carbon black, zinc oxide, calcium oxide,
Examples include lead dioxide, titanium oxide, diatomaceous earth, glass fibers and their crushed materials (such as cut glass, milled glass, and glass flakes), talc, and mica. Examples of the antioxidant include a hindered phenol-based antioxidant [Irganox 1010 (manufactured by Ciba-Geigy)] and a hindered amine-based antioxidant [Sanol LS770 (manufactured by Ciba-Geigy)]. Examples of the ultraviolet absorber include a triazole-based ultraviolet absorber [such as Tinuvin 320 (manufactured by Ciba-Geigy)] and a benzophenone-based ultraviolet absorber [such as Siasorb UV9 (manufactured by Cyanamid)].

The method for producing the curable composition of the present invention is not particularly limited. In the case of a one-pack type, preferably, the prepolymer containing terminal NCO, a plasticizer, a filler, and other additives are sufficiently removed under reduced pressure. After kneading, a curing catalyst is added (at this time, the curing catalyst may be dissolved in a solvent such as toluene), and the mixture is further sufficiently kneaded under reduced pressure. In the case of the two-pack type, a curing agent sufficiently mixed with a curing agent, a filler, a plasticizer, a curing accelerating catalyst and other additives,
It can be obtained by mixing the main component containing the contained prepolymer as a main component before construction.

[0029]

EXAMPLES The present invention will be further described below with reference to examples, but the present invention is not limited to these examples. In the following, parts and% indicate parts by mass and% by mass, respectively.

Production Example 1 Polypropylene glycol (number average molecular weight 2000) 3
0 parts and 60 parts of a propylene oxide adduct of trimethylolpropane (number-average molecular weight 4000) are placed in a reaction vessel, and dehydrated at 120 ° C. under a reduced pressure of 30 mmHg to reduce the water content to 0.03% or less. Then, it is cooled to 80 ° C.
I10 parts were charged into a reaction vessel and reacted at 80 ± 5 ° C. for 4 hours to obtain a prepolymer having a terminal NCO content of 1.9%.

Example 1 To 100 parts of the prepolymer of Production Example 1, 60 parts of dried calcium carbonate, 15 parts of dried titanium oxide, and a methyl etherified product of both ends of a propylene oxide adduct of bisphenol A as a plasticizer (number average molecular weight) 2000) 50
Parts, xylene 20 parts, hindered phenolic antioxidant (Irganox 1010, Nippon Ciba Geigy Co., Ltd.)
3 parts, triazole ultraviolet absorber (Tinuvin 32)
0, manufactured by Nippon Ciba Geigy Co., Ltd.)
Knead at normal pressure for 1 hour. Then, colloidal silica 10
At normal temperature, normal pressure for 30 minutes, normal temperature, 30 mmH
The mixture was kneaded under reduced pressure of 30 g for 30 minutes to obtain a one-part curable composition. Next, the composition was poured into a mold and cured at 20 ° C. for 7 days to obtain a cured product sheet having a thickness of 3 mm.

Example 2 The plasticizer of Example 1 was replaced with one terminal butyl ether of a random copolymer of ethylene oxide and propylene oxide,
The other terminal methyl ether compound (number average molecular weight 150
0, a one-part cured product and a cured product sheet were obtained in the same manner as in Example 1 except that the weight ratio of ethylene oxide / propylene oxide was changed to 2/8).

Comparative Example 1 Example 1 was repeated except that the plasticizer of Example 1 was replaced with a polyester plasticizer (polyester of adipic acid, polypropylene glycol (number average molecular weight 400) and 2-ethylhexanol; number average molecular weight 3000). As in 1
A liquid cured product and a cured product sheet were obtained.

Production Example 2 Polypropylene glycol (number average molecular weight 2000) 2
3 parts and 57 parts of a propylene oxide adduct of glycerin (number average molecular weight 5000) were placed in a reaction vessel,
Dehydrate under a reduced pressure of 30 mmHg to reduce the water content to 0.03% or less. Next, the mixture was cooled to 80 ° C., and 15.4 parts of MDI was charged into the reaction vessel and reacted at 80 ± 5 ° C. for 4 hours to obtain a prepolymer having a terminal NCO content of 2.6%.

Example 3 100 parts of prepolymer containing terminal NCO of Production Example 2, 80 parts of polypropylene glycol dimethyl ether (number average molecular weight 3000) as a plasticizer, 120 parts of surface-treated calcium carbonate, hindered phenolic antioxidant (Irganox) 1010, manufactured by Nippon Ciba Geigy Co., Ltd.)
Parts, 2 parts of a triazole-based ultraviolet absorber (Tinuvin 320, manufactured by Nippon Ciba Geigy Co., Ltd.), 3 parts of a curing accelerator (lead octoate), and 62 parts of a curing agent (polypropylene glycol, number average molecular weight 2000) in a planetary mixer. Then, the mixture was kneaded under reduced pressure for 30 minutes to obtain a two-part curable composition. Next, the composition was poured into a mold and cured at 20 ° C. for 7 days to obtain a cured product sheet having a thickness of 3 mm.

Example 4 A two-part cured product and a cured product sheet were obtained in the same manner as in Example 3 except that the plasticizer was changed to trimethyl ether of propylene oxide adduct of glycerin (several molecular weight: 4000).

Comparative Example 2 The procedure of Example 3 was repeated, except that DOP was used as the plasticizer.
A one-pack type cured product and a cured product sheet were obtained.

The cured sheets of Examples 1 to 4 and Comparative Examples 1 and 2 were tested for stain resistance, coating film softening property and weather resistance. (1) Stain resistance test The cured product sheet was left outdoors for one month, and the presence or absence of stains was visually checked. ○: No dirt, △: Slight dirt, ×: Large dirt

(2) Test for softening of paint film An acrylic emulsion paint was applied to the surface of the cured product sheet, dried at 20 ° C. for 7 days, left at 60 ° C. for 1 month, and palpated with a fingertip. Then, the presence or absence of softening was confirmed. ○: No softening of coating film, △: Slight softening, ×: Large softening

(3) Weather Resistance Test The cured product sheet was treated with a sunshine weatherometer (WEL).
-SUN-HCH type: Suga Test Machine Co., Ltd.)
The presence or absence of cracks on the sheet surface after 500 hours and 1000 hours of the cycle test was visually confirmed. ：: no cracks occurred, △: slight cracks occurred, ×: large cracks occurred

[0041]

[Table 1]

[0042]

Since the composition of the present invention has no bleed-out of the plasticizer, the cured product has a higher stain resistance, a higher coating film stability and a better crack resistance after aging as compared with the conventional polyurethane-based curable composition. It is a composition whose generation has been significantly improved. Due to the above effects, the composition of the present invention is useful as a paint, a waterproof material, a floor material, a sealing material, and the like.

Claims (2)

[Claims] 1. A polyurethane-based curable composition comprising a polyether compound (A) represented by the following general formula (1) as a plasticizer. Z-｛(R ¹ O) _n R ² ｝ _m (1) (where m is a number of 1 to 6, n is a number of 4 to 150, and Z is m
R ¹ represents an alkylene group or substituted alkylene group having 1 to 24 carbon atoms, and R ² represents a monovalent hydrocarbon group. ) 2. The polyurethane-based curable composition according to claim 1, wherein the number average molecular weight of the polyether compound (A) is from 500 to 8,000.