JPH11269451A - Polysulfide-type sealing material composition - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a polysulfide-type sealing material composition which can give a surface-tack-free cured product without detriment to the excellent performances (weather resistance, durability, reduced contamination of substrate, etc.), of a polysulfide type irrespectively of the curing environment. SOLUTION: There is provided a polysulfide-type sealing material composition containing the following base (A) and the following curing agent (B), wherein base A contains a liquid paraffin: (A) a base mainly consisting of a polysulfide ether polymer having at least two thiol groups in the molecule, and (B) a curing agent comprising a compound having at least two isocyanate groups in the molecule.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a polysulfide-based sealing material composition for forming an elastic sealant.

[0002]

2. Description of the Related Art Durability class 90 of JIS A 1439
In No. 30, three types of modified silicone sealant, polysulfide sealant, and acrylic urethane sealant are described as two-component elastic sealants. Among them, the polysulfide-based sealant has both excellent weather resistance and durability, and has an excellent advantage that contamination of a finish coating material is small when a paint finish is performed. Examples of such a polysulfide-based sealant include a polymer having two or more thiol groups in a molecule, a polyisocyanate compound having two or more isocyanate groups in one molecule, and a molecular sieve in which amines are occluded. A curable composition containing the composition has been proposed (JP-A-9-3153).

[0003]

However, the curable composition described in JP-A-9-3153 cannot sufficiently eliminate the residual tack on the surface of the cured product, and furthermore, the residual tack on the surface of the cured product. However, there is a problem that it is easily affected by the curing environment of the sealing material.

[0004] The present invention has been made in view of such circumstances, and while maintaining the excellent performance of a polysulfide-based material (weather resistance, durability, low contamination to a finish coating material, and the like),
An object of the present invention is to provide a polysulfide-based sealing material composition that can eliminate residual tack on the surface of a cured product without being affected by the curing environment of the sealing material.

[0005]

In order to achieve the above object, a polysulfide-based sealing material composition of the present invention comprises a polysulfide-based sealing material composition containing the following main component (A) and curing agent (B): Wherein the main agent (A) contains liquid paraffin. (A) A main ingredient mainly composed of a polysulfide ether polymer having two or more thiol groups in one molecule. (B) a curing agent comprising a compound having two or more isocyanate groups in one molecule.

That is, the inventor of the present invention has developed a cured product which is not affected by the curing environment of a sealing material while maintaining the excellent performance of a polysulfide-based material (weather resistance, durability, contamination to a finish coating material, etc.). Intensive research has been conducted to obtain a polysulfide-based sealing material composition capable of eliminating residual tack on the surface. As a result, as the main agent (A),
The present inventors have found that by using the above specific polysulfide ether polymer and liquid paraffin in combination, the liquid paraffin can suppress the stickiness of the surface after curing and achieve the intended purpose, and have reached the present invention.

The content ratio of the liquid paraffin is adjusted to the specific polysulfide ether polymer 10
By setting the content in the range of 3.5 to 20 parts by weight with respect to 0 parts by weight, the adhesiveness with the paint when performing the coating finish is excellent, the contamination to the finish coating material is small, and the adhesion to various adherends is reduced. The adhesiveness is further improved.

[0008]

Next, an embodiment of the present invention will be described.

[0009] The polysulfide-based sealing material composition of the present invention can be obtained by using a specific base material (A) and a curing agent (B).

The above-mentioned specific base agent (A) can be obtained by containing a specific polysulfide ether polymer as a main component and adding liquid paraffin thereto. In addition, that the above-mentioned specific polysulfide ether polymer is the main component means that the specific polysulfide ether polymer is the only reaction component in the whole main component (A).

The specific polysulfide ether polymer serving as a component of the main agent (A) has two or more thiol groups in one molecule. The position of the thiol group is not particularly limited, but is preferably located at the end of the molecular skeleton. Although it does not specifically limit as said specific polysulfide ether polymer, The polyether part represented by the following general formula (1) in a main chain, and the following general formula (2) and general formula ( 3) containing a structural unit represented by the formula (3), and
_{2 H 4 OCH 2 OC 2 H} 4 -SH and / or -CH
Those having ₂ CH (OH) thiol groups represented by CH ₂ -SH are particularly preferred. -(RO) _n -... (1) [In the formula (1), R represents an alkylene group having 2 to 4 carbon atoms, and n represents a positive number of 6 to 200. ] _{- (C 2 H 4 OCH 2} OC 2 H 4 -S x -) - ... (2) - _{[CH 2 CH (OH) CH 2} -S x - ] - ... (3) [Equation (2), ( In 3), x represents a positive number of 1 to 5. ]

In the polysulfide ether polymer, the polyether moiety represented by the general formula (1) and the structural units represented by the general formulas (2) and (3) are bonded in an arbitrary sequence. May be. The proportion is as follows: the polyether portion represented by the general formula (1) is 2 to 95% by weight, and the structural unit represented by the general formula (2) is 3 to 70% by weight. General formula (3)
Is preferably 1 to 50% by weight. The content of the polysulfide bond S _x is 1 to
Preferably it is 60% by weight.

The average molecular weight of the above specific polysulfide ether polymer is preferably from 600 to 200,000, particularly preferably from 800 to 50,000.

The specific polysulfide ether polymer can be produced, for example, according to the method described in JP-A-4-363325.

The liquid paraffin constituting the main component (A) together with the above specific polysulfide ether polymer is a mixture of a liquid saturated hydrocarbon of extremely high purity, which belongs to a lubricating oil fraction in terms of boiling point, and is an alkylnaphthenic hydrocarbon. Means a mixture mainly composed of The liquid paraffin is obtained by subjecting crude oil to normal pressure and reduced pressure distillation, removing the gas, gasoline, kerosene, and diesel oil components, removing the engine oil fraction from the spindle oil, and extracting the solvent with liquid sulfurous acid, furfural, etc., or hydrogenating it. After removing some unsaturated components, aromatics and sulfur, etc., and then thoroughly treating with fuming sulfuric acid in several stages, alkali neutralization, alcohol extraction, etc. and finally active under vacuum It can be obtained by adsorption treatment with clay, activated alumina, silica gel or the like.

The content ratio of the liquid paraffin is preferably set in the range of 3.5 to 20 parts, more preferably 6 to 100 parts by weight (hereinafter abbreviated as "parts") of the specific polysulfide ether polymer. ~ 12 parts. That is, if the liquid paraffin content is less than 3.5 parts, the residual tack on the surface of the cured product tends to increase, and if it exceeds 20 parts, the adhesion to the paint when performing the coating finish is poor, and This is because the contamination of the coating material is large, and the adhesiveness to various adherends tends to be poor.

The average molecular weight of the liquid paraffin is 36
The range of 0 to 470 is preferable, and the average molecular weight is particularly preferably 400 to 450. That is, the average molecular weight is 36.
If it is less than 0, the liquid paraffin bleeds to the surface,
There is a risk of adverse effects such as contamination, and the average molecular weight is 4
If it exceeds 70, the residual tack on the surface of the cured product tends to increase. Preferable specific examples of the liquid paraffin include Smoyl P-230 (average molecular weight 412) and Smoyl P-Made manufactured by Matsumura Oil Research Institute.
260 (average molecular weight 424) and Smoyl P-300 (average molecular weight 447).
Is preferred.

As the curing agent (B) used together with the main agent (A), a compound having two or more isocyanate groups in one molecule is used. As the above compound,
There is no particular limitation, and examples thereof include an organic polyisocyanate compound, a urethane prepolymer obtained by reacting the above-mentioned organic polyisocyanate compound with an active hydrogen-containing compound, and the like, and these are used alone or in combination of two or more.

The organic polyisocyanate compound is not particularly restricted but includes, for example, tolylene diisocyanate, diphenylmethane diisocyanate, polymethylene polyphenyl isocyanate, xylylene diisocyanate, isophorone diisocyanate, hexamethylene diisocyanate and the like.

The active hydrogen-containing compound is not particularly limited, and may be, for example, a hydroxyl-terminated polyester, a polyvalent polyalkylene ether, a hydroxyl-terminated polyurethane polymer, an acrylic polyol having a hydroxyl group introduced into an acrylic copolymer, a hydroxyl-terminated polybutadiene, or a polybutadiene. Alkane, alkene, aliphatic thiol including polyvalent polythioether, polyacetal, aliphatic polyol, alkylene thiol having two or more isocyanate groups, polysulfide polymer having a thiol group at a terminal, aromatic, aliphatic,
Diamines including heterocyclic diamines, and mixtures thereof, and the like.

The average molecular weight of the urethane prepolymer obtained by reacting the above active hydrogen-containing compound with an organic polyisocyanate compound is preferably from 800 to 20,000,
Particularly preferably, it is 800 to 15,000.

The mixing ratio (solid weight ratio) of the main agent (A) and the curing agent (B) is preferably set in the range of A / B = 4/1 to 8/1, and particularly preferably. A / B =
5/1 to 7/1. That is, if the ratio of the main agent (A) exceeds 8, the curing failure tends to occur easily, and if the ratio of the main agent (A) is less than 4, foaming tends to occur. .

The polysulfide-based sealing material composition of the present invention comprises the above-mentioned main agent (A) and curing agent (B)
Can be prepared by blending and mixing by a known method. The polysulfide-based sealing material composition of the present invention contains the above-mentioned main agent (A) and curing agent (B).
In addition to the above, other components may be appropriately added, and examples thereof include a filler, a curing catalyst, a plasticizer, and a stabilizer.

The filler is not particularly limited and includes, for example, calcium carbonate, talc, clay, titanium oxide, silica and the like, and may be used alone or in combination of two or more.

The curing catalyst is not particularly limited.
For example, tertiary amine catalysts, metal catalysts and the like can be mentioned, and these can be used alone or in combination of two or more. Examples of the tertiary amine catalyst include triethylenediamine, triethylamine, tri-n-butylamine, pentamethyldiethylenetriamine, N, N-dimethylcyclohexylamine, N, N-dicyclohexylmethylamine, and tetramethyl-1,3-diaminopropane. Etc. are given,
Examples of the metal-based catalyst include dibutyltin diacetate, dibutyltin dilaurate, dibutyltin malate, and lead octylate.

The plasticizer is not particularly restricted but includes, for example, dioctyl phthalate, dibutyl phthalate and the like, and may be used alone or in combination of two or more.

The stabilizer is not particularly limited and includes, for example, oleyl alcohol, phosphites, vulcanization accelerators and the like, and may be used alone or in combination of two or more.

Next, examples will be described together with comparative examples.

[0029]

Examples 1 to 5 The components shown in Table 1 below were blended in the proportions shown in the table to prepare main ingredients. Next, the curing agents shown in Table 1 below were blended in the proportions shown in the same table, and mixed to prepare a target sealing material composition.

[0030]

[Table 1]

[0031]

Examples 6 to 9 The liquid paraffin in Example 1 was
Liquid paraffin having an average molecular weight shown in Table 2 below was used. Otherwise, in the same manner as in Example 1, the intended sealing material composition was prepared.

[0032]

[Table 2]

[0033]

Comparative Example 1 except that no liquid paraffin was used.
In the same manner as in the above, a sealing material composition was prepared.

Using the sealing material compositions of Examples 1 to 9 and the sealing material compositions of Comparative Examples thus obtained, a comparison of tensile adhesion, durability, weather resistance and tack was made according to the following criteria. An evaluation was performed. The results are shown in Tables 3 and 4 below.

[Tensile Adhesion] The above sealing material composition was used as an elastic sealant having a predetermined shape.
The tensile adhesive strength was measured according to 1439. The tester used for the measurement was RTM- manufactured by Orientec.
250.

[Durability] The cured elastic sealant was subjected to a durability test by a test method according to JIS A 1439, durability class 9030.

[Weather resistance]
The test piece was cast in a size of mm × 50 mm × 10 mm and cured at 20 ° C. for 7 days, and then at 50 ° C. for 7 days. The test piece was irradiated for 200 hours using a sunshine weather meter tester. For the evaluation of weather resistance, the surface of the test piece was visually observed to determine the presence or absence of deterioration.

[Tack] The above sealing material composition was added to 10
℃ 45% RH, 20 ℃ 60% RH, 30 ℃ 70%
Each was left under the condition of RH, and after 3 days, the tack on the surface was evaluated by finger touch. As a result, ◎ indicates that the finger does not stick at all and has no tack, も の indicates that the finger does not stick much, and has little tack, △ indicates that the finger slightly sticks, and △ indicates that the finger sticks or sticks considerably. Certain items were indicated as x.

[0039]

[Table 3]

[0040]

[Table 4]

From the results shown in Tables 3 and 4, from Example 1
The sealing material compositions of No. 9 to No. 9 have excellent tensile adhesion, durability and weather resistance, and can eliminate the residual tack on the surface of the cured product regardless of the curing environment. On the other hand, the sealing material composition of the comparative example has the same excellent tensile adhesiveness, durability and weather resistance as those of the examples, but has a large residual tack on the surface of the cured product, and furthermore has a hardening environment for the sealing material. You can see that it is easily influenced by

[0042]

As described above, the polysulfide-based sealing material composition of the present invention comprises a main agent (A) containing a specific polysulfide ether polymer as a main component and a compound having two or more isocyanate groups in one molecule. And the main agent (A) further contains liquid paraffin. Therefore, as a result of the liquid paraffin suppressing the stickiness of the surface after curing, there is no residual tack on the surface of the cured product, and the residual tack on the surface of the cured product can be eliminated without being affected by the curing environment of the sealing material. It has excellent effects. In addition, since the sealing material composition of the present invention uses the above-mentioned specific polysulfide ether polymer as a main component of the main agent (A), it has both excellent weather resistance and durability properties, and performs paint finishing. In this case, there is also an effect that contamination to the finish coating material is small.

Then, the content ratio of the liquid paraffin is adjusted to the specific polysulfide ether polymer 10
By setting the range of 3.5 to 20 parts with respect to 0 parts,
It is excellent in adhesion to paint when performing paint finishing, has less contamination to the finish coating material, and is more excellent in adhesion to various adherends.

Claims (2)

[Claims] 1. A polysulfide-based sealing material composition containing the following main component (A) and curing agent (B), wherein the main component (A) contains liquid paraffin. Sealant composition. (A) A main ingredient mainly composed of a polysulfide ether polymer having two or more thiol groups in one molecule. (B) a curing agent comprising a compound having two or more isocyanate groups in one molecule. 2. The polysulfide-based sealing material composition according to claim 1, wherein the content ratio of the liquid paraffin is in the range of 3.5 to 20 parts by weight based on 100 parts by weight of the polysulfide ether polymer.