JPH1135819A - Moisture curing type one pack polyurethane resin sealing material composition and its production - Google Patents

Abstract

PROBLEM TO BE SOLVED: To obtain the subject sealing material composition excellent in storage stability and curing properties, by including a terminal isocyanate group- containing urethane prepolymer, an oxazolidine compound and two kinds of silyl esters different in function. SOLUTION: This composition comprises a terminal isocyanate group- containing urethane prepolymer, an oxazolidine compound of formula I (R<3> is a 2-6C alkylene; R<4> and R<5> are each H, a >=1C alkyl or the like; R<6> is a 2-6C alkylene or the like; R<7> is a group obtained by removing an isocyanate group from a polyisocyanate containing (q) isocyanate groups; (q) is 1-4), 0.1-20 pts.wt. based on 100 pts.wt. of the urethane prepolymer of a silyl ester compound of formula II (R<1> is a 10-20C hydrocarbon; (m) is 1-3) as a dehydrating agent and 0.01-10 pts.wt. of a silyl ester compound of formula III (R<2> is H or a 1-9C hydrocarbon; (n) is 1-3) as a latent quick curing agent.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

The present invention relates to a moisture-curable one-pack polyurethane resin sealing material composition having excellent storage stability and curability, and a method for producing the same.

[0002]

2. Description of the Related Art Conventionally, various polyurethane resin compositions have been used for sealing materials, joint materials, adhesives, paints, waterproof materials,
Widely used as flooring materials. Such a polyurethane resin composition is composed of a two-pack type resin composition composed of a polyol compound and an isocyanate compound, and a one-pack type resin composition that is cured by moisture in the air or moisture adsorbed by the compounded compound. Although a resin composition is known, in recent years, it is not necessary to adjust the mixing of the resin composition in on-site construction and the handling is easy.
The use of liquid polyurethane resin compositions is expanding. The cross-linking curing reaction of the moisture-curable one-component polyurethane resin composition (hereinafter, referred to as one-component urethane composition) starts from the surface of the construction site and proceeds to the inside. For this reason, it takes a long time from half a day to a whole day until the used composition is completely cured. Therefore, conventionally, tin or lead organometallic compounds such as stannas octoate and dibutyltin dilaurate, or tertiary amines such as triethylamine or triethylenediamine and N-methylmorpholine are used alone or in combination and cured. Time has been reduced. However, the one-pack type urethane composition to which such a curing catalyst has been added has a problem that although the curing time is shortened, the storage stability is reduced.

[0003] In order to solve these problems and to realize a one-pack type urethane composition having good curability and storage stability, a curing catalyst containing a small decrease in storage stability is used.
Various types of liquid urethane compositions and one-pack urethane compositions containing additives for improving storage stability have been proposed. For example, Japanese Patent Publication No. 4-11564 discloses a moisture-curable urethane sealing material obtained by adding and mixing a specific tin compound as a catalyst for promoting curing. Japanese Patent Application Laid-Open No. 4-59811 discloses a one-pack type urethane composition containing 0.05 to 5% by weight of bis (dimethylmorpholine) ethyl ether as a curing catalyst. Japanese Patent Application Laid-Open No. 4-149270 discloses a one-pack type urethane composition obtained by adding a halide of an alkaline earth metal, particularly calcium chloride, as an additive for improving storage stability. However, these conventional one-part urethane compositions do not always provide satisfactory storage stability. JP-A-7-138336
Japanese Patent Application Laid-Open Publication No. H11-175, discloses a one-pack type urethane composition comprising an oxazolidine compound, a silyl ester compound and a monoisocyanate compound. In this one-pack type urethane composition, the silyl ester compound acts as a crosslinking accelerator for promoting the polymerization of the oxazolidine compound and the urethane prepolymer, and the monoisocyanate compound acts as a water-trapping agent and a ring-opening oxazolidine compound scavenger in the system. This one-pack type urethane composition attempts to solve the problems of curability and storage stability, but the degree of the solution is not always sufficient.

[0004]

SUMMARY OF THE INVENTION An object of the present invention is to provide a moisture-curable one-pack polyurethane resin sealing material composition having excellent fast-curing properties and excellent storage stability, and a method for producing the same.

[0005]

That is, the present invention provides: 1) a urethane prepolymer having a terminal isocyanate group, 2) an oxazolidine compound, and 3) a compound having a silyl ester group represented by the formula (1). For 100 parts by weight of the urethane prepolymer,
0.1 to 20 parts by weight, and 4) a compound having a silyl ester group represented by the formula (2) based on 100 parts by weight of the urethane prepolymer.
A moisture-curable one-pack polyurethane resin sealing material composition containing 0.01 to 10 parts by weight.

Embedded image (In Formula (1), R ¹ represents a hydrocarbon group having 10 to 20 carbon atoms, and m represents an integer of 1 to 3. In Formula (2), R ² represents a hydrogen atom or a carbon atom having 1 to 9 carbon atoms. Wherein n is 1 to
Represents an integer of 3. )

Further, the present invention provides: 1) a reaction product of a urethane prepolymer having a terminal isocyanate group and an oxazolidine compound; and 2) a compound having a silyl ester group represented by the above formula (1). 0.1 to 20 parts by weight with respect to 100 parts by weight of the polymer; 3) 0.01 to 10 parts by weight of the compound having a silyl ester group represented by the formula (2) with respect to 100 parts by weight of the urethane prepolymer. Curable one-pack polyurethane resin sealing material composition comprising:

Further, the present invention provides a compound having a silyl ester group represented by the above formula (2) after blending a compound having a silyl ester group represented by the above formula (1) to remove water in the blending system. Provided is a method for producing a moisture-curable one-pack polyurethane resin sealing material composition, characterized by incorporating a compound.

[0008]

DESCRIPTION OF THE PREFERRED EMBODIMENTS The present invention will be described below in detail.
The moisture-curable one-pack polyurethane resin sealing material composition of the present invention (hereinafter referred to as the composition of the present invention) contains two types of silyl ester compounds having different functions in addition to the urethane prepolymer and the oxazolidine compound. Features. Further, the method for producing the composition of the present invention comprises mixing two types of silyl ester compounds having different functions at different timings, that is, mixing a silyl ester compound which releases a carboxylic acid having a long carbon chain by hydrolysis. First, after removing water in the system to enhance storage stability, then, as a latent fast curing catalyst for the oxazolidine compound, which is a latent fast curing agent, a silyl ester compound that releases a carboxylic acid having a short carbon chain by hydrolysis. To form a composition. The silyl ester compound which releases a carboxylic acid having a short carbon chain by this hydrolysis promotes a curing reaction when the composition is cured.

The urethane prepolymer having a terminal isocyanate group used in the present invention means that the isocyanate group part forms a urethane bond due to the presence of water.
It is a compound that becomes a polymer by crosslinking and curing, and is a reaction product of a polyhydroxyl compound and a polyisocyanate compound.

The urethane prepolymer having a terminal isocyanate group used in the present invention may be any urethane prepolymer produced from a polyol which is a kind of polyhydroxyl compound and polyisocyanate, and is not particularly limited.

The polyol is a general term for alcohols in which a plurality of hydrogens of a hydrocarbon are substituted with hydroxyl groups. For example, one or more alkylene oxides such as ethylene oxide, propylene oxide, butylene oxide and tetrahydrofuran are used. A product obtained by addition polymerization of a compound having two or more active hydrogens. Here, examples of the compound having two or more active hydrogens include polyhydric alcohols, amines, alkanolamines, and polyhydric phenols. As polyhydric alcohols, ethylene glycol, propylene glycol, butanediol, diethylene glycol, glycerin, hexanetriol, trimethylolpropane, pentaerythritol, etc., and as amines, ethylenediamine, hexamethylenediamine, etc., alkanolamines Examples thereof include ethanolamine and propanolamine, and examples of the polyhydric phenols include resorcinol and bisphenols.

Specifically, polyolefin polyols such as polytetramethylene glycol, polyethylene glycol, polypropylene glycol, polyoxypropylene glycol, polyoxybutylene glycol polyether polyol, polybutadiene polyol, polyisoprene polyol, and other adipate polyols; Lactone-based polyols, polyester-based polyols such as castor oil, and the like are preferable, and these polyols can be used in combination as necessary. These compounds may be used alone or in combination of two or more, but the weight average molecular weight is preferably about 100 to 10,000, more preferably about 500 to 7000.

As the polyisocyanate compound, various compounds used in the production of ordinary polyurethane resins can be used. Specifically, 2,4-tolylene diisocyanate or 2,6-tolylene diisocyanate, diphenylmethane-4,4-diisocyanate and modified products thereof, 1,5-naphthalenediisocyanate, tolidine diisocyanate And naphthalene, hexamethylene diisocyanate, isophorone diisocyanate, xylylene diisocyanate and the like. These polyisocyanate compounds may be used alone or in combination of two or more.

In the production of a urethane prepolymer having a terminal isocyanate group, the ratio of the polyhydroxyl compound to the polyisocyanate compound is such that the number of hydroxyl groups in the polyhydroxyl compound is one or less per isocyanate group in the polyisocyanate compound. The ratio is preferably 0.50 to 0.95. The production conditions for the urethane prepolymer may be the ordinary production conditions for the urethane prepolymer. That is, the above-mentioned hydroxyl compound and polyisocyanate compound are reacted at a reaction temperature of 50.
What is necessary is just to make it react under normal pressure at about 100 degreeC.

The oxazolidine compound used in the present invention is
It is a compound represented by the following formula (3) or (4).

[0016]

Embedded image

In the formula (3), R ³ is an alkylene group having 2 to 6 carbon atoms, more preferably an alkylene group having 2 carbon atoms. R ⁴ and R ⁵ are each independently a hydrogen atom, an alkyl group having 1 or more carbon atoms, an alicyclic alkyl group having 5 to 7 carbon atoms, or an aryl group having 6 to 10 carbon atoms. R ⁶ is an alkylene group having 2 to 6 carbon atoms or an alkylene group having 2 to 6 carbon atoms including a urethane bond, and is preferably an alkylene group having 1 to 5 carbon atoms having a urethane bond, or an aryl group. R ⁷ represents a group obtained by removing an isocyanate group from a polyisocyanate having q isocyanate groups,
It is preferable that the compound be a skeleton of the isocyanate compound. q is an integer of 1 to 4, and is preferably 2 or 3. In the formula (4), R ³ , R ⁴ , R ⁵ , R ⁶
Has the same meaning as R ³ , R ⁴ , R ⁵ and R ⁶ in the formula (3).
The oxazolidine compound used in the present invention may be a compound represented by the formula (3), a compound represented by the formula (4), or a combination of both.

The oxazolidine compound is hydrolyzed with water to form a secondary amine, causing a crosslinking reaction, and functions as a latent curing agent. Secondary amines react with isocyanate groups to form urea bonds. At this time, if a carboxylic acid having a short carbon chain is present in the system, hydrolysis of the oxazolidine compound is promoted, and the oxazolidine compound is promptly reacted with an isocyanate group to form a urea bond, thereby promoting a crosslinking reaction.
The timing of adding the oxazolidine compound may be at the time of synthesizing the urethane prepolymer, or at the time of synthesizing the composition of the present invention using the urethane prepolymer, the later-described silyl ester compound, or the like. But,
When the oxazolidine compound represented by the formula (4) is used, it is preferable to add the compound at the time of synthesizing the urethane prepolymer and react it with the urethane prepolymer.

The oxazolidine compound represented by the formula (4) can be produced by a usual method such as a method by a dehydration condensation reaction of an alkanolamine with a ketone or an aldehyde. The oxazolidine compound represented by the formula (3) can be produced, for example, by an addition reaction of the oxazolidine compound represented by the formula (4) with a polyisocyanate compound. The amount of the oxazolidine compound represented by the formula (3) is preferably 0.1 to 2 equivalents to the NCO equivalent of the urethane prepolymer. If the amount is less than 0.1 equivalent, the curing speed is low, and if it exceeds 2 equivalents, the storage stability is deteriorated. More preferably,
0.2-0.8 equivalents. The amount of the oxazolidine compound represented by the formula (4) is preferably 0.05 to 0.5 equivalent based on the NCO equivalent of the urethane prepolymer. If it is less than 0.05 equivalent, the curing speed is slow, and
Above the equivalent, it is stoichiometrically unsuitable.

The composition of the present invention is characterized by containing two kinds of silyl ester compounds having different functions. The two types of silyl ester compounds are a compound having a silyl ester group represented by the following formula (1) and a compound having a silyl ester group represented by the following formula (2).

[0021]

Embedded image

In the formula (1), R ¹ represents a hydrocarbon group having 10 to 20 carbon atoms, and m represents an integer of 1 to 3. In the formula (2), R
² is a hydrogen atom or a hydrocarbon group having 1 to 9 carbon atoms,
n represents an integer of 1 to 3. The silyl ester compound used in the present invention is a compound in which a siloxane bond (—Si—O—) contains Si.
An atom having a hydrocarbon group having 1 to 3 carbon atoms, and / or
It may be a polymer ester to which an alkyl ester group is bonded, or not a polymer but one Si atom.
It may be a hydrocarbon group having 1 to 3 carbon atoms or a monomer ester to which an alkyl ester group is bonded.

The silyl ester compound used in the present invention can be produced from a carboxylic acid and a silanol, but a commercially available silyl ester compound can also be used. For example, the compound having a silyl ester group represented by the formula (1) includes a silyl ester compound A represented by the following formula (5), and the compound having a silyl ester group represented by the following formula (2) includes A silyl ester compound B represented by the formula (6) and a silyl ester compound C represented by the following formula (7) (SZ6075, manufactured by Dow Corning Toray Co., Ltd.) can be exemplified. In the formula, the degree of polymerization p is represented by the formula (5):
The silyl ester compound B represented by the formula (6) is about 30 in both cases.

[0024]

Embedded image

The compound having a silyl ester group of the formula (1), for example, the silyl ester compound A is preferably used in the process of preparing the composition of the present invention, preferably at an early stage of compounding, for example, after synthesizing a urethane prepolymer. Before compounding other compounds, compounding the filler with the urethane prepolymer, before compounding other additives, or compounding the oxazolidine compound, the filler with the urethane prepolymer,
It is added before compounding other additives and functions as a dehydrating agent. That is, in the process of preparing the composition of the present invention, in the initial stage of blending various compounds, the blended silyl ester group of the formula (1) is formed by a very small amount of water present in the blending system. The ester bond of the compound having the compound is hydrolyzed, thereby removing water in the system. This improves the storage stability of the composition.
The carboxylic acid generated at this time is a carboxylic acid having 10 to 20 carbon atoms and a long carbon chain (referring to R ¹ in the formula (1)). A carboxylic acid having a long carbon chain has a low acidity and does not cause a reaction with an oxazolidine compound or an isocyanate group during long-term storage, so that storage stability is not adversely affected. Further, the carboxylic acid having a long carbon chain binds to the surface of a filler, for example, a calcium carbonate filler or the like incorporated in the composition, functions as a thixotropic agent, and gives the composition a good thixotropy. The compound having a silyl ester group of the formula (1), for example, the silyl ester compound A is compounded in an amount of 0.1 to 20 parts by weight, preferably 1 to 10 parts by weight based on 100 parts by weight of the urethane prepolymer. is there. The above range is preferable from the viewpoint of storage stability.

The compound having a group having a silyl ester group of the formula (2), for example, the silyl ester compound B, is preferably such that the compound having a silyl ester group of the formula (1) sufficiently removes water in the compounding system. Added after
For this reason, it exists in a compounding system in the form of an ester without being hydrolyzed, and is hydrolyzed by moisture in the air when the composition is used. The carboxylic acid generated at this time has 1 to 1 carbon atoms.
9 is a carboxylic acid having a short carbon chain (in the formula (2), R ² ). Carboxylic acids with short carbon chains have high acidity,
Activates oxazolidine compounds and isocyanate groups to promote hydrolysis and curing reactions. Therefore, the compound having a silyl ester group represented by the formula (2) functions as a latent fast-curing catalyst that imparts fast-curing properties without any adverse effect on the storage stability of the composition. The compound having a silyl ester group of the formula (2), for example, the silyl ester compound B is used in an amount of 0.01 to 10 parts by weight, preferably 0.1 to 5 parts by weight, based on 100 parts by weight of the urethane prepolymer.
Parts by weight. It is preferable that it is in the above range from the viewpoint of quick-curing properties.

The composition of the present invention contains a carbodiimide compound, a monoisocyanate compound, a filler, a plasticizer, an antioxidant, a pigment, a silane coupling agent, a dispersant, a solvent and the like in addition to the above essential compounds. You may.

The carbodiimide compound is contained in the compound incorporated in the system in the form of water of crystallization or the like, and acts to trap moisture that promotes crosslinking between isocyanate groups and ring-opening of the oxazolidine ring and accompanying crosslinking. This contributes to the improvement of storage stability.

Since the reactivity of the isocyanate group in the monoisocyanate compound is higher than that of the isocyanate group in the urethane prepolymer,
Acts as a water scavenger in the system. Also, commercially available oxazolidine compounds contain ring-opened compounds, which promote the cross-linking reaction between isocyanate groups of the urethane prepolymer and reduce storage stability. Must be removed from the system. The monoisocyanate compound also has a function of capturing such a ring-opened oxazolidine compound. As such a monoisocyanate compound, a commercially available product can be used, and examples thereof include Additive TI (manufactured by Bayer AG). The compounding amount of the monoisocyanate compound is preferably 0.1 to 10 parts by weight based on 100 parts by weight of the urethane prepolymer.
This is because if it is within the range, it is preferable from the viewpoint of curability and storage stability.

As the filler, surface-treated calcium carbonate, carbon black, clay, talc, titanium oxide,
Examples include quicklime, kaolin, zeolite, diatomaceous earth, vinyl chloride paste resin, glass balloons, and vinylidene chloride resin balloons. These fillers can be used alone or as a mixture.

Examples of the plasticizer include dioctyl phthalate (DOP), dibutyl phthalate (DBP), dilauryl phthalate (DLP), dibutyl benzyl phthalate (BBP), dioctyl adipate, diisodecyl adipate, trioctyl phosphate, and tris (chloroethyl). ) Phosphate, tris (dichloropropyl) phosphate, propylene glycol adipate polyester, butylene glycol adipate polyester, alkyl epoxystearate, epoxidized soybean oil and the like. These plasticizers can be used alone or as a mixture.

As antioxidants, butylhydroxytoluene (BHT), butylhydroxycyanisole (B
HA), diphenylamine, phenylenediamine, triphenyl phosphite and the like. As pigments, titanium dioxide, zinc oxide, ultramarine, red petals, lithbon,
Inorganic pigments such as lead, cadmium, iron, cobalt, aluminum, hydrochloride, and sulfate; and organic pigments such as azo pigments and copper phthalocyanine pigments. Examples of the solvent include aromatic hydrocarbon solvents such as xylene and toluene.

Next, a method for producing the moisture-curable one-pack polyurethane resin sealing material composition of the present invention will be described. The method for producing a moisture-curable one-pack polyurethane resin sealing material composition of the present invention is characterized by blending two kinds of silyl ester compounds having different functions at different timings. That is, in the method for producing the composition of the present invention, first, a polyhydroxyl compound and a polyisocyanate compound are reacted at a predetermined quantitative ratio to obtain a urethane prepolymer. When synthesizing urethane prepolymer, if necessary,
A plasticizer may be blended. Next, an oxazolidine compound represented by the formula (3) or (4) is added to the urethane prepolymer, and a compound having a silyl ester group represented by the formula (1) is blended. Alternatively, a predetermined amount of the oxazolidine compound represented by the formula (3) or (4) and a filler are mixed and reacted with the urethane prepolymer to obtain a urethane prepolymer mixture, and then the formula (1)
And a compound having a silyl ester group represented by The compound having a silyl ester group of the formula (1) is preferably added at an early stage of compounding the compound contained in the composition of the present invention. In the compound having a silyl ester group represented by the formula (1), the ester bond is hydrolyzed by water present in the system such as the surface of the compound to be blended, thereby removing the water in the system. . This improves the storage stability of the resulting composition. The carboxylic acid generated by hydrolysis of the compound having a silyl ester group represented by the formula (1) is a carboxylic acid having a long carbon chain. A carboxylic acid having a long carbon chain has a low acidity and does not react with an oxazolidine compound or an isocyanate group during long-term storage, and therefore does not deteriorate storage stability. Next, after adding other additives such as a solvent as necessary, a compound having a silyl ester group represented by the formula (2) is blended to obtain a sealing material composition. As described above, the oxazolidine compound may be added at the time of synthesizing the urethane prepolymer, or may be added at the time of adding other additives such as a solvent. However, when the oxazolidine compound is the compound represented by the formula (4), it is more preferable to mix the compound at the time of synthesizing the urethane prepolymer. The compound having a silyl ester group represented by the formula (2) is not hydrolyzed because the compound having the silyl ester group represented by the formula (1) is mixed after water in the system is removed.
It exists in the form of an ester and is hydrolyzed by moisture in the air when the sealing material composition is used. The carboxylic acid generated by hydrolysis of the compound having a silyl ester group represented by the formula (2) is a carboxylic acid having a short carbon chain. A carboxylic acid having a short carbon chain has a high acidity and reacts with an oxazolidine compound or an isocyanate group to promote a hydrolysis reaction and a crosslinking curing reaction. That is, the compound having a silyl ester group represented by the formula (2) functions as a latent rapid curing catalyst, and improves the curability of the obtained sealing material composition. In the production method of the present invention, each compound is preferably kneaded sufficiently under reduced pressure or an inert atmosphere, and uniformly dispersed to form a composition according to the timing of mixing the silyl ester compound.

Since the composition of the present invention has the above constitution and is produced by the above production method, it is possible to achieve both storage stability and curability. Therefore, the composition of the present invention is suitable as a moisture-curable one-pack polyurethane resin sealing material.

[0035]

EXAMPLES The present invention will be described in more detail with reference to the following examples, but it should not be construed that the present invention is limited thereto.

(Production Example: Example 1) 500 parts by weight of polyoxypropylene triol having three hydroxyl groups and having an average molecular weight of 6000 (manufactured by Asahi Glass Co., Ltd.), and an average molecular weight of 300
740 parts by weight of polyoxypropylene diol and 536 parts by weight of dioctyl phthalate are placed in a reaction vessel.
Dehydration treatment was performed at 10 ° C. and 10 mmHg for 24 hours. Then, a mixture of 100 parts by weight of 2,4-tolylene diisocyanate and 2,6-tolylene diisocyanate (mixing ratio, 2,4-TDI: 2,6-TDI = 80: 2)
0) and stirred at 80 ° C. for 6 hours under a nitrogen atmosphere,
It was confirmed that the NCO group content was 1.06% by weight. 37 parts by weight of oxazolidine compound A (see the following formula (8)) was added to the reaction solution, and the mixture was stirred at 60 ° C. for 2 hours under a nitrogen atmosphere. 142.5 parts by weight of the obtained mixture of the urethane prepolymer and the oxazolidine compound (including 100 parts by weight of the urethane prepolymer, 2.7 parts by weight of the oxazolidine compound, and 40 parts by weight of dioctyl phthalate) were added to the surface-treated calcium carbonate (Maruo calcium 140
Parts by weight and 3.3 parts by weight of the silyl ester compound A represented by the formula (5) were added and kneaded under reduced pressure (10 mmHg or less) for 1 hour. Next, mineral spirit (manufactured by Nippon Oil Co., Ltd.) was added, and the mixture was stirred under reduced pressure for 10 minutes. Then, 1 part by weight of the silyl ester compound B represented by the formula (6) was added, and the mixture was stirred under reduced pressure for 10 minutes. After stirring, a polyurethane resin sealing material composition was obtained.

[0037]

Embedded image

Example 2 A composition was obtained in the same manner as in Example 1 except that 0.5 parts by weight of the silyl ester compound B was used. (Example 3) A composition was obtained in the same manner as in Example 1, except that 0.38 parts by weight of the silyl ester compound C represented by the formula (7) was used instead of the silyl ester compound B.

Comparative Example 1 A composition was obtained in the same manner as in Example 1, except that 0.1 parts by weight of 2-ethylhexanoic acid was used instead of the silyl ester compound B. (Comparative Example 2) A composition was obtained in the same manner as in Example 1 except that the silyl ester compound B was not blended. Comparative Example 3 A composition was obtained in the same manner as in Example 1 except that the silyl ester compound A was not blended.

The curability and storage stability of the compositions obtained in Examples and Comparative Examples were measured and evaluated by the following methods. (1) Tack free time (evaluation of curability) The composition was adhered to a polyethylene film under the conditions of 20 ° C. and a relative humidity of 60%, and the time until adhesion did not occur was measured. Tack free time. (2) Thixo Index (Evaluation of Storage Stability) BS Viscometer No. No. manufactured by Tokyo Keiki Co., Ltd. The initial viscosity and the viscosity after storage were measured at 20 ° C. and 1 rpm / 10 rpm using a 7 rotor. The viscosity after storage was measured after the composition was left in an atmosphere at 70 ° C. for 24 hours (hereinafter, also referred to as storage stability promotion test). The ratio (%) of the viscosity after storage to the initial viscosity was determined as the rate of change. (3) Evaluation From the values of tack free time and thixo index, storage stability and rapid curing property were evaluated. In the table, ○
Indicates that the respective properties were good, and x indicates that the properties were not good. Table 1 shows the results.

[0041] In the table, the unit of the compound is part by weight. * 1, * 2: Due to the increase in viscosity, the viscosity after storage could not be measured. Therefore, the rate of change in viscosity could not be calculated.

Comparative Example 1 is an example in which silyl ester compound A and 2-ethylhexylic acid, which is a carboxylic acid having a short carbon chain, are blended. Initially showed good fast-curing properties, but during long-term storage, 2-ethylhexanoic acid activated the oxazolidine compound A or the isocyanate group of the urethane prepolymer, increasing the viscosity, making it unsuitable for use. As indicated by the accelerated storage stability test. Comparative Example 2 is an example in which only the silyl ester compound A was blended. Although the storage stability promotion test showed good storage stability, the initial tack-free time was 6 hours and 30 minutes because the silyl ester compound B functioning as a latent fast curing catalyst was not blended. Was too slow to be practical. Comparative Example 3 is an example in which only silyl ester compound B was blended. Initially showed good fast-curing properties, but since silyl ester compound A functioning as a dehydrating agent was not blended, silyl ester compound B was hydrolyzed during long-term storage, resulting in a short carboxylic acid having a carbon chain. It was shown by the storage stability promotion test that the oxazolidine compound and the isocyanate group of the urethane prepolymer were activated to increase the viscosity due to liberation. In addition, it did not contain stearic acid, which is a carboxylic acid having a long carbon chain functioning as a thixotropic agent, and thus had poor thixotropy. Examples 1, 2,
3 was prepared by mixing a silyl ester compound A functioning as a dehydrating agent and a thixotropic agent in the initial stage of compounding, and after sufficiently dehydrating, compounding a silyl ester compound B or a silyl ester compound C functioning as a latent fast curing catalyst. It showed that it had sufficient fast-curing property and good storage stability.

[0043]

The composition of the present invention has a short curing time and is excellent in storage stability. Therefore, the composition of the present invention cures quickly after casting, allows quick application of paints and the like, and is useful as a sealing material having good workability even after long-term storage. Further, according to the method for producing a composition of the present invention, it is possible to produce a composition having good curability without impairing storage stability.

Continued on the front page (51) Int.Cl. ⁶ Identification symbol FI C09K 3/10 C09K 3/10 D // C08G 18/22 C08G 18/22 18/30 18/30 Z

Claims (3)

[Claims] 1. An urethane prepolymer having a terminal isocyanate group, 2) an oxazolidine compound, and 3) a compound having a silyl ester group represented by the formula (1), based on 100 parts by weight of the urethane prepolymer.
0.1 to 20 parts by weight, and 4) a compound having a silyl ester group represented by the formula (2) based on 100 parts by weight of the urethane prepolymer.
A moisture-curable one-pack polyurethane resin sealing material composition containing 0.01 to 10 parts by weight. Embedded image (In Formula (1), R ¹ represents a hydrocarbon group having 10 to 20 carbon atoms, and m represents an integer of 1 to 3. In Formula (2), R ² represents a hydrogen atom or a carbon atom having 1 to 9 carbon atoms. Wherein n is 1 to
Represents an integer of 3. ) 2. A method comprising the steps of: 1) reacting a urethane prepolymer having a terminal isocyanate group with an oxazolidine compound; and 2) a compound having a silyl ester group represented by the formula (1) in 100 parts by weight of the urethane prepolymer. On the other hand,
0.1 to 20 parts by weight, and 3) a compound having a silyl ester group represented by the formula (2) based on 100 parts by weight of the urethane prepolymer.
A moisture-curable one-pack polyurethane resin sealing material composition containing 0.01 to 10 parts by weight. Embedded image (In Formula (1), R ¹ represents a hydrocarbon group having 10 to 20 carbon atoms, and m represents an integer of 1 to 3. In Formula (2), R ² represents a hydrogen atom or a carbon atom having 1 to 9 carbon atoms. Wherein n is 1 to
Represents an integer of 3. ) 3. A compound having a silyl ester group represented by the above formula (1) is blended with a compound having a silyl ester group represented by the above formula (2) after removing water in the blending system. The method for producing a moisture-curable one-pack polyurethane resin sealing material composition according to claim 1 or 2, wherein: