JPH10121031A - Sealant composition - Google Patents

Abstract

PROBLEM TO BE SOLVED: To obtain a sealant composition having a long pot life, reduced in foaming and giving a cured product having good properties by mixing a polymer having at least two thiol groups with a curing catalyst comprising a tert. amine, etc., an isocyanate compound and an acid phosphoric ester. SOLUTION: This composition comprises a polymer (A) having at least two thiol groups in the molecule, a compound (B) having at least two isocyanate groups in the molecule, a curing catalyst (C) comprising a tert. amine and/or an organometallic compound and an acid phosphoric ester (D) as a cure retardant. Component A is particularly desirably a thiol-terminated polysulfide or polysulfide polyether polymer having a number-average molecular weight of 500/800-50,000. Component B is desirably a urethane prepolymer obtained from an organic polyisocyanate and an active hydrogen compound. Component D is desirably an alkyl acid phosphate having 500KOHmg/g or below. This composition has a long pot life even under high-temperature high-humidity conditions and can give a good cured product.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a sealant composition, and more particularly to a sealant composition which can be cured after a sufficient pot life after mixing a main agent and a curing agent, and exhibit good physical properties.
The present invention also relates to a sealing material composition suitable for use in a wide range of temperature and humidity to give a cured product with less foaming.

[0002]

2. Description of the Related Art A polymer containing two or more thiol groups in one molecule is easily cured when mixed with an oxidizing agent, and the thiol group easily reacts with an epoxy group, an isocyanate group or the like to increase the molecular weight. From sealing materials, paints,
Widely used for adhesives.

Examples of such a thiol group-containing polymer include a polysulfide polymer described in US Pat. No. 2,466,963 and a polysulfide polyether polymer described in JP-A-4-363325.

In Japanese Patent Application Laid-Open No. 52-125563, the above-mentioned polysulfide polymer is used.
No. 121 proposes a curable composition suitable for a sealing material, which is obtained by curing the polysulfide polyether polymer with an isocyanate compound, has less foaming, has good weather resistance, and can easily obtain a white cured product. Was done.

[0005]

However, a composition comprising such a polymer containing a thiol group and a tertiary amine and / or an organometallic catalyst is prepared, and two or more compounds are formed in one molecule.
When a compound having two or more isocyanate groups is cured under high temperature and high humidity, or cured after storage under high temperature and high humidity, the working life is often shortened and the workability may be deteriorated. Was. Further, in such a case, when an organic acid which is a curing retarder is used and the amount thereof is increased, there is a problem that the physical properties of the cured product are reduced and foaming is increased.

Accordingly, an object of the present invention is to provide a high-temperature, high-humidity
It is another object of the present invention to provide a sealing material composition that has a long pot life, a short rise in curing, and little foaming even after storage under high temperature and high humidity, and a cured product that expresses a sufficient modulus with good reproducibility is obtained. .

[0007]

As a result of intensive studies in view of the above-mentioned object, the present inventors have found that a polymer comprising a polymer having two or more thiol groups in a molecule and a tertiary amine and / or an organometallic catalyst is used. When the composition is stored under high temperature and high humidity or under high temperature and high humidity, and then cured with a compound having two or more isocyanate groups in a molecule, a predetermined amount of an acidic phosphate ester is added as a curing retarder. As a result, it has been found that a sufficient pot life can be ensured, foaming is small, and good cured physical properties can be obtained. That is, the sealing material composition of the present invention comprises (a) a polymer having two or more thiol groups in a molecule, (b) a compound having two or more isocyanate groups in a molecule, (c) ( 1) a curing catalyst comprising a tertiary amine and / or (2) an organic metal; and (d) a sealing material composition containing an acidic phosphate compound as a curing retarder.

[0008]

BEST MODE FOR CARRYING OUT THE INVENTION Hereinafter, the present invention will be described in detail. [1] Polymer having two or more thiol groups in a molecule Polymer having two or more thiol groups in a molecule used in the present invention (hereinafter, simply referred to as thiol group-containing polymer)
The polymer skeleton portion of polyether, polythioether, polyester, acrylic copolymer, urethane copolymer, polyacetal, polybutadiene, polyisoprene, polyolefin, polychloroprene, polysulfide and those having the structure of these copolymers are preferable. . Particularly, a polysulfide polymer having a polysulfide structure and a polysulfide polyether polymer are preferable. The position of the thiol group is not particularly limited, but is preferably located at the end of the molecular skeleton. (1) polysulfide polymer polysulfide polymer, in the main chain, _{(b) - (C 2 H 4 OC} n H 2n OC 2 H 4 -Sx) - ( where, n is an integer of 1 to 2, x is 1-5 of an integer. represented contain a structural unit, and the terminal in), _{(ii) -C 2 H 4 OC n H} 2n OC 2 H 4 -SH ( where, n is 1-2 Is an integer.).

Such a polysulfide polymer has fluidity at room temperature and has a number average molecular weight (Mn) of usually 10
0 to 200,000, preferably 400 to 50,
000. Preferred examples of such polysulfide polymers are described in U.S. Pat. No. 2,466,963. (2) polysulfide polyether polymer polysulfide polyether polymer, in the main chain (c) - (R ¹ O) m-(where, R ¹ is an alkylene group having 2 to 4 carbon atoms, m is 6
Indicates an integer of 200. A polyether moiety represented by), _{(d) - (C 2 H 4 OC} n H 2n OC 2 H 4 -S x) -,
And-(CH ₂ CH (OH) CH ₂ -S _x )-(where n is an integer of 1 to 2, and x is an integer of 1 to 5). and the terminal, _{(e) -C 2 H 4 OC n H} 2n OC 2 H 4 -SH and /
Or a compound having a thiol group represented by —CH ₂ CH (OH) CH ₂ —SH (where n is an integer of 1 to 2).

In this polysulfide polyether polymer, the polyether portion of (c) and the structural unit of (d) may be bonded in an arbitrary sequence, and the ratio thereof is-(R ¹ O ) M-component is 2-95
_{Wt%, - (C 2 H 4} OC n H 2n OC 2 H 4 -S X) -
Component is 3 to 70 _{wt%, - (CH 2 CH (} OH) CH 2
It is preferable that the amount of the component (S _X )-is 1 to 50% by weight.
The content of the polysulfide bond S _x is 1 to 60.
Preferably, it is weight%.

The number average molecular weight (Mn) of the polysulfide polyether polymer is usually from 600 to 200,0.
00, preferably 800 to 50,000.

Such a polysulfide polyether polymer can be produced, for example, by the method described in JP-A-4-363325. [2] Compound Having Two or More Isocyanate Groups in the Molecule The compound used in the present invention that contains two or more isocyanate groups in the molecule (hereinafter, simply referred to as an isocyanate group-containing compound) includes an organic polyisocyanate compound and / or Urethane prepolymers obtained by reacting an organic polyisocyanate compound with an active hydrogen-containing compound are preferred.

Specific examples of the organic polyisocyanate compound include tolylene diisocyanate, diphenylmethane diisocyanate, polymethylene polyphenyl isocyanate (crude MDI), xylylene diisocyanate, isophorone diisocyanate, and hexamethylene diisocyanate.

Examples of the active hydrogen-containing compound include a hydroxyl group-terminated polyester, a polyvalent polyalkylene ether, a hydroxyl group-terminated polyurethane polymer, an acrylic polyol obtained by introducing a hydroxyl group into an acrylic copolymer, a hydroxyl group-terminated polybutadiene, a polyvalent polythioether, a polyacetal. Aliphatic polyols, and alkanes including alkylene thiols having two or more SH groups, alkenes and aliphatic thiols, polysulfide polymers having terminal SH groups,
Diamines, including aromatic, aliphatic and heterocyclic diamines, and the like, and mixtures thereof.

As the urethane prepolymer, those obtained by reacting the above-mentioned active hydrogen-containing compound with an organic polyisocyanate compound under the condition of an excess of isocyanate compound can be used.

In the present invention, the molar ratio (isocyanate group / thiol group) of the isocyanate group in the isocyanate group-containing compound to the thiol group in the thiol group-containing compound is 0.5 to 4.0, preferably 0.1 to 4.0. It mix | blends so that it may be set to 7-3.0. If the molar ratio is less than 0.5, the composition does not have a sufficiently high molecular weight, while if it exceeds 4.0, the cured product becomes hard and brittle, which is not preferable. [3] Tertiary amine, organometallic compound (1) Tertiary amine As the tertiary amine in the present invention, monoamines, diamines, triamines, polyamines, cyclic amines, alcohol amines, ether amines and the like are exemplified. Yes,
Specific examples include triethylamine, N, N-dimethylcyclohexylamine, N, N, N ′, N′-tetramethylethylenediamine, N, N, N ′, N′-tetramethylpropane-1,3-diamine, N , N, N ', N'
-Tetramethylhexane-1,6-diamine, N, N,
N ', N ", N" -pentamethyldiethylenetriamine, N, N, N', N ", N" -pentamethyldipropylenetriamine, tetramethylguanidine, N, N-dipolyoxyethylenestearylamine, N, N -Dipolyoxyethylene tallow alkylamine, triethylenediamine, N, N'-dimethylpiperazine, N-methyl-N '
-(2 dimethylamino) -ethylpiperazine, N-methylmorpholine, N-ethylmorpholine, N- (N ',
N'-dimethylaminoethyl) -morpholine, 1,2-
Dimethylimidazole, dimethylaminoethanol, dimethylaminoethoxyethanol, N, N, N'-trimethylaminoethylethanolamine, N-methyl-
N '-(2hydroxyethyl) -piperazine, N- (2
(Hydroxyethyl) -morpholine, bis- (2-dimethylaminoethyl) ether, ethylene glycol bis-
(3 dimethyl) -aminopropyl ether and the like.

Among them, N, N-dipolyoxyethylene alkylamine compounds are preferred because they have less residual tack of the cured product. Specific examples include N, N-dipolyoxyethylene stearylamine, N, N-dipolyoxyethylene tallow alkylamine, and the like. Two or more of these tertiary amines may be used. (2) Organometallic compound As the organometallic compound in the present invention, an organotin compound,
There are organic mercury compounds, organic lead compounds, etc.Specifically, tin octylate, dibutyltin diacetate, dibutyltin dilaurate, dibutyltin mercaptide, dibutyltin thiocarboxylate, dibutyltin maleate, dioctyltin mercaptide, dioctyltin thiocarboxylate Rate, phenylmercuric propionate, lead octenoate and the like. Among them, organotin compounds having little influence on discoloration and the like are preferable, and more preferably dialkyltin mercaptide and / or
Or dialkyltin dicarboxylates and / or dialkyltin bis (dicarboxylic acid monoalkyl ester) salts and / or
Or a dialkyltin (dicarboxylic acid) salt and the like.
Two or more of these organometallic compounds may be used.

The content of the curing catalyst (c) in the sealing material composition is determined according to (a) the polymer 10 having a thiol group.
0.001 to 5 parts by weight is preferable with respect to 0 parts by weight,
More preferably, it is 0.005 to 3 parts by weight. If the content is less than 0.001 part by weight, curing does not proceed, and if it exceeds 5 parts by weight, the pot life becomes short, which is not preferable. [4] Acidic phosphate ester As the acidic phosphate ester in the present invention, there are alkyl phosphates, phenyl phosphates, alkyl pyrophosphates and the like, and specific examples are monomethyl phosphate, dimethyl phosphate, monoisopropyl phosphate, diisopropyl phosphate. , Monobutyl phosphate, dibutyl phosphate, mono-2-
Ethylhexyl phosphate, di-2-ethylhexyl phosphate, monoisodecyl phosphate, diisodecyl phosphate, and alkyl acid phosphate, which is a mixture of these monoesters and diesters, monophenyl phosphate, diphenyl phosphate, phenyl acid phosphate, butyl pyrophosphate, which is a mixture thereof Is mentioned. Among them, 500 (KOH
mmg / g) or less, a monoalkyl phosphate, a dialkyl phosphate and / or an alkyl acid phosphate which is a mixture thereof is preferable because it has a moderate activity as a retardant, reacts with an isocyanate, and has a low tendency to lower the modulus. Specific examples include mono-2-ethylhexyl phosphate, di-2-ethylhexyl phosphate, 2-ethylhexyl acid phosphate, monoisodecyl phosphate, diisodecyl phosphate, and isodecyl acid phosphate.

The amount of the acidic phosphoric acid ester is 0.01 to 10 parts by weight based on 100 parts by weight of the polymer (a) having a thiol group. At 0.01 parts by weight or less, the effect as a retarder is small, and at 10 parts by weight or more, the effect of a decrease in the modulus of the sealant increases.

The addition method is as follows: (a) a polymer having a thiol group or a blend thereof, and (b) a compound having two or more isocyanate groups in a molecule,
When mixing and curing in the presence of the curing catalyst (c), a method of adding the mixture is preferable. If it is previously blended, the activity may be reduced due to the action with a filler or the like. In addition, when added, a plasticizer such as dioctyl phthalate or dihexyl phthalate, or a solution dissolved in an organic solvent such as toluene or xylene may be used. [5] Other Compounds (1) Filler The sealing material composition of the present invention further contains calcium carbonate, talc, and the like for the purpose of improving economy, workability when applying the composition, and physical properties after curing. , Clay, titanium oxide,
A filler such as silica can be added. (2) Plasticizer The composition of the present invention comprising (a) the above-mentioned polysulfide polyether polymer as a polymer having two or more thiol groups in a molecule and a compound having two or more isocyanate groups in a molecule is conventionally used. Dioctyl phthalate (DOP), diheptyl phthalate (D
Since cheap phthalic acid esters such as HP) are compatible, it is possible to mix these additives. In addition, a plasticizer such as chlorinated paraffin and hydrogenated terphenyl can be blended.

[0021]

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

[Synthesis Example 1] Bifunctional polypropylene glycol obtained by adding propylene oxide to propylene glycol (OH value: 56.4 mgKOH / g) 1
000 g, 107 g epichlorohydrin, 1.2
5 g of stannic chloride pentahydrate was charged into the reaction vessel,
Stirred at 90 ° C. for 3 hours. Further, after adding and mixing 1110 g of polysulfide polymer (trade name “Thiokol LP55” manufactured by Toray Thiokol Co., Ltd.), 89.9 g was mixed.
Of sodium hydrogen sulfide (purity 72.3%) at 80 ° C.
Stirred for hours. Thereafter, the salt was removed to obtain a pale yellow transparent polymer having a mercaptan content of 2.0% by weight and a viscosity of 80 poise (25 ° C.).

[Examples 1 to 3] The type and amount of the amine catalyst, the plasticizer, and the type shown in Table 1 were added to the polymer obtained in Synthesis Example 1.
The filler was blended to obtain a main ingredient. 67 parts by weight of a urethane prepolymer (4.0% by weight of isocyanate content) obtained by adding xylene diisocyanate to polypropylene glycol to 360 parts by weight of the main ingredient, Add the amount of (d) acidic phosphate and add
The mixture was uniformly mixed at a constant temperature for about 10 minutes.

The obtained mixture was 35 mm in height and 20 mm in inner diameter.
After pouring it into a mm ethylene cup and smoothing the surface,
JIS K while keeping in 20 ℃, humidity 60RH%
The penetration was measured every hour using the penetration tester used in -2207, and the time until it reached 300 was taken as the pot life. Further, JIS A-575 was used as an adherend using an aluminum plate treated with alumite sulfate using this mixture.
An H-type specimen was prepared by the method according to Example 8, and the tensile adhesion after the standard curing was measured in a room at 20 ° C. Further, the mixture was poured into a polyethylene cup having a height of 55 mm and an inner diameter of 20 mm, and the surface was smoothed.
After storing in RH% for 24 hours, the volume increase due to foaming was measured. Table 3 shows the results.

Comparative Example 1 As a comparative example, the same test as in Examples 1 to 3 was carried out, except that (d) the acidic phosphoric acid ester was not added. Table 3 shows the results.

Example 4 The same base material as in Examples 1 to 3 was stored in a thermostat at 50 ° C. for one month and then taken out.
The same test was performed. Table 3 shows the results.

Comparative Example 2 As a comparative example, the same test as in Example 4 was performed except that (d) the acidic phosphoric acid ester was not added.

Comparative Example 3 Examples 1 to 3 are comparative examples.
A similar test was conducted by adding 0.5 parts of stearic acid instead of the acidic phosphoric acid ester to the same base agent as in Example 1.

Example 5 A main agent was obtained by blending the polymer obtained in Synthesis Example 1 with the types and amounts of amine and organometallic catalysts, plasticizers and fillers shown in Table 1. This main agent 3
Urethane prepolymer obtained by adding xylene diisocyanate to polypropylene glycol to 90 parts by weight
(Isocyanate content: 4.0% by weight) 67 parts by weight and (d) acidic phosphate ester of the kind and amount shown in Table 2 were added and mixed at a constant temperature of 20 ° C. for about 10 minutes. After that, the same test as in Examples 1 to 3 was performed. Table 3 shows the results.

Comparative Example 4 As a comparative example, a similar test was carried out using the same base agent as in Example 5 except that (d) the acidic phosphoric acid ester was not added. Table 3 shows the results.

[0031]

[Table 1]

[0032]

[Table 2]

[0033]

[Table 3] As is clear from Table 3, the sealing material composition of the present invention can be cured after a sufficient pot life, exhibits good physical properties, and gives a cured product with less foaming.

[0034]

As described above in detail, the sealing material composition of the present invention is cured with an isocyanate compound by adding an acidic phosphate ester together with an amine and / or an organometallic catalyst to a polymer having a thiol group. In this case, in the case of curing after storage at high temperature and high humidity or after storage under high temperature and high humidity, sufficient pot life can be secured, foaming is small, and good cured physical properties can be obtained. Such sealant compositions are suitable for use over a wide temperature and humidity range.

Continuing from the front page (72) Inventor Yuki Echigoya 2-3 Chizukaigan, Ichihara-shi, Chiba Toraychikor Co., Ltd. Chiba Plant (72) Inventor Kazuhisa Sakae 2-3 Chizukaigan, Ichihara-shi, Chiba Toraychikor stock Inside the Chiba factory

Claims (7)

[Claims] (A) a polymer having two or more thiol groups in a molecule; (b) a compound having two or more isocyanate groups in a molecule; (c) (1) a tertiary amine; And / or (2) a sealing material composition containing a curing catalyst comprising an organic metal and (d) an acidic phosphate compound as a curing retarder. 2. The sealing material composition according to claim 1, wherein said (a) polymer having a thiol group has a molecular weight of 600 to 200,000. 3. The sealing material composition according to claim 1, wherein (a) the thiol group-containing polymer is (A)-(C ₂ H ₄ OC _n ) in the main chain. H _2n OC ₂ H ₄ -S _x )-(where n is an integer of 1 to 2, x is an integer of 1 to 5), and at the terminal, _{b) -C 2 H 4 OC n H} 2n OC 2 H 4 -SH ( where, n is represented by thio at some integer 1-2) - characterized in that it is a - polysulfide polymer having Le group. Sealant composition. 4. The sealing material composition according to claim 1, wherein (a) the thiol group-containing polymer is (C)-(R ¹ O) m- in the main chain. (However, R ¹ is an alkylene group having 2 to 4 carbon atoms, m is 6 to
Indicates an integer of 200. And ether moieties, (d) - - polyether represented _{by) (C 2 H 4 OC n} H 2n OC 2 H 4 -S X) -,
And _{- (CH 2 CH (OH)} CH 2 -S X) - ( where, n is 1-2 integer, x is an integer of 1-5.) Containing a structural unit represented by the and, at the end, _{(e) -C 2 H 4 OC n H} 2n OC 2 H 4 -SH and /
Or _{-CH 2 CH (OH) CH 2} -SH ( where, n is an integer of 1-2.) Thio represented by -
A sealing material composition, which is a polysulfide polyether polymer having a hydroxyl group. 5. The sealing material composition according to claim 1, wherein the acidic phosphate ester (d) is added in an amount of 0.1 to 100 parts by weight of the polymer (a) having a thiol group. A sealing material composition containing from 0.1 to 10% by weight. 6. The sealing material composition according to claim 1, wherein (b) an isocyanate group of a compound having two or more isocyanate groups in a molecule;
The molar ratio (isocyanate group / thiol group) to the thiol group in the polymer having the thiol group (a) is 0.5.
To 4.0. 7. The sealing material composition according to claim 1, wherein the acidic phosphate ester (d) is a monoalkyl phosphate and / or a monoalkyl phosphate having an acid value of 500 (KOH mmg / g) or less. A sealing material composition comprising a dialkyl phosphate and / or an alkyl acid phosphate which is a mixture thereof.