JP2005068402A - Two-pack type polyurethane-based sealing material - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a two-pack type polyurethane-based sealing material capable of keeping enough time available for operation, without foaming while cured, and having excellent curing performance and durability, without having an adverse effect on the environment. <P>SOLUTION: This two-pack type polyurethane-based sealing material is composed of a base material (I) which comprises (A) an isocyanate-terminated prepolymer and a curing agent (II) which contains (B) a polyoxyalkylene ether and (C) an organotin compound (curing catalyst) in an amount of 0.1-6 pts.wt. (based on 100 pts.wt. of the polyoxyalkylene ether (B)), wherein (D) an organic carboxylic acid metal salt (curing adjustor) in an amount of 0.2-9 pts.wt. (based on 100 pts.wt. of the polyoxyalkylene ether (B)) is mixed into the curing agent (II). <P>COPYRIGHT: (C)2005,JPO&NCIPI

Description

  The present invention relates to a two-component polyurethane sealant used in the civil engineering / architecture field, automobile field, electrical / electronic field, and the like.

Conventionally, lead organic carboxylates have been widely used as curing catalysts in two-component polyurethane sealing materials comprising a base composed of an isocyanate group-terminated prepolymer and a curing agent containing a polyoxyalkylene ether.
However, this catalyst has insufficient curing performance and non-foaming properties (that is, the property that the sealing material does not generate gas during curing and does not foam), and since it contains lead, there are concerns about adverse effects on the environment and the human body. .
Therefore, bismuth organic carboxylate has been proposed as a curing catalyst in place of this lead organic carboxylate (see Patent Document 1), but the pot life and non-foaming performance of the sealing material are significantly different due to a slight change in the amount of catalyst. There is a problem that it is very difficult to balance in product design and handling is difficult.
In addition, when an organotin compound (curing catalyst) that is widely used in a one-component polyurethane system is used in a two-component polyurethane system, the isocyanate group in the base is the moisture content of the filler in the curing agent and the polyalkylene ether There is a big problem that it reacts preferentially over (curing component), resulting in the generation of gas and significant foaming.

JP 2001-89549 A

  The problem to be solved by the present invention is that the workable time (usable time) cannot be sufficiently secured in the two-component polyurethane-based sealing material, gas is generated during curing, foams and contains harmful metals. Problems such as adverse effects.

The inventors of the present invention have further studied earnestly about the curing catalyst, and when the organic carboxylic acid metal salt (curing modifier) is used in combination with the organic tin compound (curing catalyst), the workable time (potential time) can be sufficiently extended, And it discovered that the foaming during hardening was suppressed remarkably and came to complete this invention.
That is, the present invention provides the following 1. ~ 5. It consists of the following.
1. First, 1st invention is (A) base (I) which consists of isocyanate group terminal prepolymer, (B) polyoxyalkylene ether, and (C) organotin compound (curing catalyst) 0.1-6 mass parts And (B) a curing agent (II) containing (based on 100 parts by mass of polyoxyalkylene ether),
(D) Organic carboxylic acid metal salt (curing modifier) 0.2-9 parts by mass (however, (B) 100 parts by mass of polyoxyalkylene ether) is blended with curing agent (II). Is a two-component polyurethane sealing material.
(C) If the amount of the organic tin compound (curing catalyst) is less than 0.1 parts by mass, it is not preferable because sufficient curability cannot be imparted, and if it exceeds 6 parts by mass, the workable time is shortened. Moreover, the compounding quantity of (C) organotin compound becomes like this. More preferably, it is 0.15-5 mass parts.
(D) If the amount of the organic carboxylic acid metal salt (curing modifier) is less than 0.2 parts by mass, the non-foaming property becomes poor, and if it exceeds 9 parts by mass, the workable time is shortened. The amount of (D) the organic carboxylic acid metal salt is more preferably 0.25 to 8 parts by mass, particularly preferably 0.5 to 6 parts by mass.

上記基剤（Ｉ）の製造に用いるポリオキシプロピレンジオールとポリオキシプロピレントリオールの質量比は、最終的に得られるシーリング材としての物性（モジュラス、伸び等）や硬化性、非発泡性を考慮して適宜選択することができる。ポリオキシプロピレンジオールは水酸基を平均２つ有し、ポリオキシプロピレントリオールは水酸基を平均３つ有している。水酸基を平均３つ有しているポリオキシプロピレントリオールを多く配合すると、つまり上記平均官能基数（ｆ）を大きく設定すると非発泡性の効果が大きくなるが、最終硬化物のモジュラスは高くなる。一方、上記平均官能基数（ｆ）を小さく設定すると、最終硬化物のモジュラスを低くできるが非発泡性の効果は低くなる。従って、上記平均官能基数（ｆ）は２．２以上３．０以下が好ましい。平均官能基数（ｆ）を３．０より大きく設定すると、最終硬化物のモジュラスが建築用に用いる場合には高くなりすぎる。そのため、シーリング材の要求性能である被着体の動きへの追従が難しくなる。但し、この追従性が余り要求されない他の用途に関しては、この限りではない。
５．第５の発明は、（Ｃ）有機錫化合物（硬化触媒）が４価の有機錫化合物であることを特徴とする上記１〜４のいずれかに記載の２成分形ポリウレタン系シーリング材である。有機錫化合物が４価の有機錫化合物であると非発泡性の効果が大きくなり好ましい。 2. According to a second aspect of the present invention, in (1) the metal of the organic carboxylic acid metal salt is calcium. 2. The two-component polyurethane sealant described in 1. (D) It is preferable that the metal of the organic carboxylic acid metal salt is calcium since the non-foaming effect is increased.
3. Furthermore, the third invention is characterized in that (D) the carboxylic acid of the organic carboxylic acid metal salt is octylic acid. Or 2. 2. The two-component polyurethane sealant described in 1.
(D) It is preferable that the carboxylic acid of the organic carboxylic acid metal salt is octylic acid because stability during storage is improved. If it is naphthenic acid, the dispersibility during production is slightly inferior.
In particular, it is particularly preferable that the organic carboxylic acid metal salt (D) is calcium octylate because a non-foaming effect, stability during storage, and sufficient workable time can be imparted. When calcium naphthenate is used, the same effect as calcium octylate is obtained, but the dispersibility during production is slightly inferior.
4). 4th invention is characterized by the average functional group number (f) defined by the following formula | equation (1) of the base (I) consisting of an isocyanate group terminal prepolymer being 2.2 or more and 3.0 or less. The two-component polyurethane sealing material according to any one of the above 1 to 3. When the average number of functional groups (f) of the base (I) comprising the isocyanate group-terminated prepolymer is 2.2 or more, the effect of non-foaming property is increased, which is preferable.

The mass ratio of polyoxypropylene diol and polyoxypropylene triol used in the production of the base (I) is determined in consideration of physical properties (modulus, elongation, etc.), curability and non-foaming properties as a finally obtained sealing material. Can be selected as appropriate. Polyoxypropylene diol has an average of 2 hydroxyl groups, and polyoxypropylene triol has an average of 3 hydroxyl groups. If a large amount of polyoxypropylene triol having an average of 3 hydroxyl groups is blended, that is, if the average number of functional groups (f) is set large, the effect of non-foaming properties will be increased, but the modulus of the final cured product will be increased. On the other hand, when the average functional group number (f) is set small, the modulus of the final cured product can be lowered, but the non-foaming effect is lowered. Therefore, the average functional group number (f) is preferably 2.2 or more and 3.0 or less. If the average functional group number (f) is set to be larger than 3.0, the modulus of the final cured product becomes too high when used for construction. Therefore, it becomes difficult to follow the movement of the adherend, which is the required performance of the sealing material. However, this is not the case for other applications that do not require much followability.
5). A fifth invention is the two-component polyurethane sealant according to any one of the above 1 to 4, wherein the (C) organotin compound (curing catalyst) is a tetravalent organotin compound. It is preferable that the organic tin compound is a tetravalent organic tin compound because the non-foaming effect is increased.

  According to the present invention, it is possible to provide a two-component polyurethane sealant that can secure a sufficient workable time, does not foam during curing, has excellent curing performance, and does not adversely affect the environment.

The mass ratio of polyoxypropylene diol and polyoxypropylene triol is added to a urethane polymerization apparatus equipped with a stirrer, heating apparatus, vacuum dehydration apparatus, and nitrogen stream apparatus of (A) isocyanate group-terminated prepolymer as base (I). Charge as 0-10 / 10-0. After dehydration under reduced pressure at 120 ° C., nitrogen substitution was performed, and after cooling to about 50 ° C. under a nitrogen stream and adding a polyisocyanate compound calculated so that the NCO / OH ratio was 1.60 to 2.00, 80 to If it reacts at 100 degreeC for about 4 to 8 hours, and the isocyanate content rate of a design value is reached, after cooling as a reaction end point, it stores in a closed container, purging with nitrogen.
At this time, a small amount of a polymerization catalyst such as dibutyltin dilaurate (DBTDL) may be blended at an arbitrary stage.
Moreover, polyoxypropylene diol and polyoxypropylene triol may be mixed in advance and simultaneously act with polyisocyanate, or may be allowed to act stepwise.
You may use polyoxyalkylene tetraol etc. which are more multifunctional.

  The polyisocyanate compound will be further described. Conventionally known compounds can be widely used. For example, 2,4-toluene diisocyanate, 2,6-toluene diisocyanate, 4,4′-diphenylmethane diisocyanate, 2,4′-diphenylmethane. Diisocyanate, phenylene diisocyanate, polyphenylmethane diisocyanate, xylylene diisocyanate, naphthalene diisocyanate and their hydrogenated compounds, hexamethylene diisocyanate, isophorone diisocyanate, 1,3-bisisocyanate cyclohexane, triphenylmethane diisocyanate, cyclohexyl diisocyanate, tetramethylxylylene Examples thereof include range isocyanate and norbornane diisocyanate. These polyisocyanates are used alone or in combination of two or more. Among these polyisocyanates, isomer mixtures of 2,4-toluene diisocyanate and 2,6-toluene diisocyanate, isomer mixtures of 4,4′-diphenylmethane diisocyanate and 2,4′-diphenylmethane diisocyanate, xylylene diisocyanate, isophorone diisocyanate Hydrogenated xylylene diisocyanate, hydrogenated diphenylmethane diisocyanate and the like are preferable, and among these polyisocyanates, isomer mixtures of 2,4-toluene diisocyanate and 2,6-toluene diisocyanate are particularly preferable.

Concerning Preparation of Curing Agent (II) (B) Polyoxyalkylene ether (hereinafter sometimes referred to as polyol) is different from (A) isocyanate group-terminated prepolymer (hereinafter sometimes referred to as prepolymer) and is dependent on moisture. Since there is no influence, a polyol or mixed polyol is charged into a processing pot capable of kneading and processing a sealed high-viscosity product, and (C) an organic tin compound (curing catalyst), (D) an organic carboxylic acid metal salt (curing modifier) , An amine curing catalyst, an inorganic filler such as calcium carbonate, a viscosity improver such as anhydrous silica and amide wax, a colorant, an anti-aging agent, and a dehydrating agent such as quicklime are mixed and mixed uniformly.
In addition, when viscosity adjustment is required, high-boiling solvents such as plasticizers such as DOA, N-methyl-2-pyrrolidone, aliphatic hydrocarbons and aromatic hydrocarbons, dibasic acid esters, etc., are only used as curing agents. It can mix | blend with a base instead.
In addition, if it further demonstrates about the polyol used for base (I) and hardening | curing agent (II), a conventionally well-known thing can be used widely, for example, polyoxyalkylene ether, polyester polyols, polybutadiene polyols, for example. Acrylic polyols, polycarbonate polyols, castor oil-based polyols, low molecular weight diols, trimethylolpropane, glycerin, sorbitol, mannitol and the like can be used. Polyoxyalkylene ether is particularly preferable. Specific examples include polypropylene glycol, polyethylene glycol, polyethylene propylene glycol, and polytetramethylene glycol.

As the organotin compound (C) in the present invention, conventionally known organotin compounds can be used as curing catalysts for silicone, modified silicone, polyurethane and the like. For example, tin octylate, tin naphthenate, tin stearate as divalent organic tin compounds, dibutyltin dioctoate, dibutyltin dilaurate, dioctyltin diversate, dibutyltin bistriethoxysilicate, dibutyltin dioleyl as divalent organic tin compounds Malate, dibutyltin diacetate, 1,1,3,3-tetrabutyl-1,3-dilauryloxycarbonyl-distannoxane, dibutyltinoxybisethoxysilicate, dibutyltin oxide, reaction of dibutyltin oxide with phthalate Products, a reaction product of dibutyltin oxide and maleic acid diester, and divalent tin diacetylacetonate as a hexavalent organic tin compound. These catalysts may be used alone or in combination of two or more.
Examples of the organic carboxylic acid metal salt (D) in the present invention include metal salts such as octylic acid, neodecanoic acid, and naphthenic acid. In particular, octeric acid metal salts have good dispersibility during production, and octylic acid calcium salts have good stability during storage. Since an organic carboxylic acid metal salt alone cannot be expected to be effective as a curing catalyst, it must be used in combination with an organotin compound as a curing catalyst. The organic carboxylic acid metal salt is usually diluted with a solvent such as mineral spirit.

Preparation ratio of two-component polyurethane sealant composition (A) The blending ratio of prepolymer and curing agent (II) is the number of isocyanate groups calculated from the isocyanate content of (A) prepolymer. The number of hydroxyl groups is calculated from the hydroxyl group content of the (B) polyol component in the curing agent (II), and the ratio (NCO / OH ratio) is 0.90 to 1.30, preferably 1.05 to 1. Each blending amount is determined to be in a range of .25.
The base (I) (A) prepolymer and curing agent (II) are uniformly mixed at a construction site, construction site, or the like by a sealing material mixer and filled in various joints.
The sealing material is painted with various paints for the purpose of hiding joints, improving cosmetics and protecting the sealing material if necessary after curing.

The non-foaming property, curability, workability (workable time), and durability of the two-component polyurethane sealants prepared in the following examples and comparative examples were investigated and evaluated by the following test methods.
"Test method"
Non-foamable (A) prepolymer base and curing agent were mixed at a ratio of 1: 4 (mass ratio, base / curing agent NCO / OH ratio = 1.06), immediately 15 mm in diameter and 50 mm in height. After filling the cylindrical plastic container with the bottom so that bubbles do not enter and smoothing it, it was cured in an oven at 50 ° C. for 24 hours and then taken out.
The height at which the cured product expanded from the container was measured, and the amount of foaming was calculated by the following equation.
Foaming ratio = raised height (mm) / 50 (mm) x 100 (%)
When this value is large, there is a possibility that the sealing material filled in the actual joint may rise and swell from the joint, and it is preferable that this value is as low as possible. In addition, this test method is a test under a very severe condition where the filling volume of the sealing material is small and the curing conditions are as high as 50 ° C., and the results can be understood in a short period of time.
In order to prevent blistering when an actual joint is filled with a sealing material, the foaming ratio calculated by this test method needs to be smaller than 10%. That is, if the foaming ratio is 10% or more, blistering may occur, and if it is smaller than 10%, there is no problem of blistering.
Therefore, evaluation of non-foaming property was performed as follows.
Foaming ratio less than 10% ...
Foaming ratio 10% or more

Curing (A) Prepolymer base and curing agent are allowed to stand in a constant temperature room at 23 ° C. overnight to adjust the temperature, and then the base and curing agent are weighed and mixed at a ratio of 1: 4 in the constant temperature room at 23 ° C. Then, a sheet having a thickness of 10 mm was prepared, and the cured state after 1 day was examined by finger touch at 23 ° C. and 55% RH, and the evaluation of curability was as follows.
Fully exhibiting rubber elasticity ...
Slightly plastic deformation ...
Those that do not recover due to plastic deformation ...

Workability (workable time)
(A) The prepolymer base and curing agent are allowed to stand in a temperature-controlled room at 23 ° C. overnight to adjust the temperature, and then the base and curing agent are weighed and mixed in a ratio of 1: 4 in the temperature-controlled room at 23 ° C. After filling a cylindrical plastic container with a bottom of 50 mm in diameter and 50 mm in height so that bubbles do not enter and smoothing it, in the penetration meter for petroleum asphalt of JIS K 2207, needle + A needle having a total weight of 12.5 g was used, and this needle was allowed to fall freely for 5 seconds vertically over the sealing material filled in the container over time. As the base and curing agent react and cure progresses, the sealing material thickens, and the length of the needle that falls over time decreases. The workable time was measured as the time during which the length of the needle drop was 35 mm (that is, constant viscosity). If this measured time is 2 hours or more, the workability is good until the end of the work even at the actual site, and if it is shorter than 2 hours, the sealing material thickens in the middle of the work and the workability deteriorates. It becomes difficult to use. Therefore, the workability was evaluated as follows.
Measured time is more than 2 hours ...
The measured time is less than 2 hours ...
As the required performance of the durability sealant, it is required to follow the joint movement due to expansion and contraction due to temperature change and horizontal displacement during an earthquake, etc., and maintain the waterproof function. A 1439: 1997 Durability test (Category 8020). The test results were evaluated as follows depending on whether or not clear abnormalities such as “dissolution”, “swelling”, “cracking”, and “peeling from the adherend” occurred for the three test specimens.
There is no clear abnormality ...
Clear anomalies ...

[Example 1]
(Manufacture of base)
Bifunctional polypropylene glycol (average molecular weight 2000, average number of hydroxyl groups 2, trade name Actol P-21, manufactured by Mitsui Takeda Chemical Co., Ltd.) 500 g, trifunctional polypropylene glycol (average molecular weight 3000, average number of hydroxyl groups 3, trade name Actol) 400 g of P-31, manufactured by Mitsui Takeda Chemical Co., Ltd.) and 100 g of a bifunctional polypropylene glycol (average molecular weight 1000, average number of hydroxyl groups 2, trade name Actol P-22, manufactured by Mitsui Takeda Chemical Co., Ltd.) 100 g 171 g of toluene diisocyanate (trade name Cosmonate T-80, manufactured by Mitsui Takeda Chemical Co., Ltd.) was added and reacted at 80 ° C. for 4 hours, with an NCO content of 3.1% and an average functional group number (f) of 2.3. The base of the isocyanate group terminal urethane prepolymer (A) was obtained.
(Manufacture of curing agent)
200 g of trifunctional polypropylene glycol (average molecular weight 5000, average number of hydroxyl groups 3, trade name Actol 87-34) 100 g, bifunctional polypropylene glycol (average molecular weight 4000, average number of hydroxyl groups 2, trade name Actol P-28) 100 g, dioctyltin 3 g of diversate (curing catalyst), 2 g of calcium octylate (curing modifier), 300 g of colloidal calcium carbonate (trade name, Homocal DM, manufactured by Shiraishi Kogyo Co., Ltd.), heavy calcium carbonate (trade name, Softon BF100, Bihoku powdered 400 g (manufactured by Kogyo Co., Ltd.) was thoroughly mixed with a planetary mixer and then rolled, and vacuum degassed to obtain a curing agent.
Next, the base and the curing agent were mixed at a ratio of 1: 4 (mass ratio, base / curing agent NCO / OH ratio = 1.06), and non-foaming property, curability, and Workability (workable time) was examined.

[Comparative Example 1] to [Comparative Example 3]
In the production of the curing agent, a two-component polyurethane-based sealing material was prepared in the same manner as in Example 1 except that zinc octylate, potassium octylate, and magnesium naphthenate were used instead of calcium octylate as the curing modifier. Non-foaming property, curability, and workability (workable time) were examined.
[Comparative Example 4] to [Comparative Example 5]
In the production of the curing agent, a two-component polyurethane-based sealing material was prepared in the same manner as in Example 1 except that calcium octylate (curing modifier) or dioctyltin diversate (curing catalyst) was not blended. Property, curability, and workability (workable time) were examined.
[Example 2] to [Example 5]
In the production of the curing agent, a two-component polyurethane sealing material is prepared in the same manner as in Example 1 except that the amount of calcium octylate added is 0.8 to 24 parts by mass. And workability (workable time) was investigated.
[Example 6] to [Example 7]
A two-component polyurethane sealant was prepared in the same manner as in Example 1 except that 0.8 or 8 parts by mass of calcium naphthenate was added instead of calcium octylate, and non-foaming property, curability, and workability ( Workable time) was investigated.

[Comparative Example 6] to [Comparative Example 7]
In the production of the curing agent, a two-component polyurethane sealant was prepared in the same manner as in Example 1 except that the amount of calcium octylate added was 0.4 or 28 parts by mass. And workability (workable time) was investigated.
[Comparative Example 8] to [Comparative Example 9]
In the production of the curing agent, a two-component polyurethane sealant was prepared in the same manner as in Example 1 except that 1 or 10 parts by mass of octylic acid was used as a curing modifier instead of calcium octylate, and non-foaming property was produced. Then, the curability and workability (workable time) were examined.
[Example 8] to [Example 13]
In the production of the curing agent, instead of 3.0 parts by mass of dioctyltin diversate (curing catalyst), 3.0 parts by mass of other organic tin compounds (curing catalyst) in Table 3 were used, and the amount of calcium octylate added was Except for increasing the amount to 8 parts by mass, a two-component polyurethane sealant was prepared in the same manner as in Example 1, and the non-foaming property, curability, and workability (workable time) were examined.
[Example 14]
Example 1 except that 1.5 parts by mass of dioctyltin diversate (curing catalyst) and 1.5 parts by mass of tin octylate are combined and the amount of calcium octylate added is increased to 8 parts by mass. A two-component polyurethane sealant was prepared and examined for non-foaming properties, curability, and workability (workable time).

[Example 15] to [Example 17]
In the production of the curing agent, the same as Example 1 except that the addition amount of dioctyltin diversate (curing catalyst) is 0.3, 5, 10 parts by mass and the addition amount of calcium octylate is increased to 8 parts by mass. Thus, a two-component polyurethane sealant was prepared and examined for non-foaming property, curability, and workability (workable time).
[Comparative Example 10] to [Comparative Example 11]
In the production of the curing agent, the same procedure as in Example 1 was carried out except that the addition amount of dioctyltin diversate (curing catalyst) was 0.1 and 20 parts by mass and the addition amount of calcium octylate was increased to 8 parts by mass. A two-component polyurethane sealant was prepared and examined for non-foaming properties, curability, and workability (workable time).
[Comparative Example 12] to [Comparative Example 14]
In the production of the curing agent, instead of using 3 parts by mass of dioctyltin diversate (curing catalyst) and 2 parts by mass of calcium octylate (curing modifier), 3 parts by mass of lead octylate or bismuth octylate (curing catalyst) ) A two-component polyurethane sealant was prepared in the same manner as in Example 1 except that only 2 to 3 parts by mass were used, and the non-foaming property, curability, and workability (workable time) were examined.
[Example 18] to [Example 20]
(A) Polyol (Actol P-22, Act) with the compounding amounts shown in Table 6 so that the average functional group number (f) of the base (I) comprising the isocyanate group-terminated prepolymer is 2.2 to 3.0. A two-component polyurethane-based sealing material was prepared in the same manner as in Example 1 except that Cole P-21 and Actol P-31) were charged and an isocyanate group-terminated prepolymer having an NCO content of 3.1% was produced. Non-foaming property, curability, and workability (workable time) were examined.
[Comparative Example 15]
(A) A polyol (Actol P-21) is charged at a blending amount shown in Table 6 so that the average number of functional groups (f) of the base (I) comprising the isocyanate group-terminated prepolymer is 2.0. A two-component polyurethane-based sealing material was prepared in the same manner as in Example 1 except that a 1% isocyanate group-terminated prepolymer was produced, and non-foaming property, curability, and workability (workable time) were obtained. Examined.
[Comparative Example 16]
(A) Polyol (Actol AE-305: tetrafunctional polypropylene glycol (Actol AE-305: tetrafunctional polypropylene glycol (A) with the compounding amount shown in Table 6 so that the average functional group number (f) of the base (I) comprising the isocyanate group-terminated prepolymer is 3.5) 2-component polyurethane in the same manner as in Example 1 except that an isocyanate group-terminated prepolymer having an average molecular weight of 500, an average number of hydroxyl groups of 4 and manufactured by Mitsui Takeda Chemical Co., Ltd.) was prepared. A system sealant was prepared and examined for non-foaming property, curability, workability (workable time), and durability.

The following Tables 1 to 6 show the blending ratios of the above Examples and Comparative Examples, and the non-foaming property, curability, and workability test results.
In addition, the additional description about Tables 1-6 is as follows.
(A) Details of Actol 87-34, Actol P-28, Actol P-22, Actol P-21, Actol P-31, Homocal DM, Softon BF100 are shown in Example 1. .
(B) Calcium octylate, zinc octylate, potassium octylate, and magnesium naphthenate are diluted with mineral spirit, hexylene glycol, white kerosene, etc., and blended into the curing agent. The amount added is indicated.
(C) In the parentheses in the evaluation column for non-foaming property and workability, specific numerical values of the foaming ratio and workable time are shown.
As is apparent from the results of Tables 1 to 6, the two-component polyurethane sealing material in which a specific amount of an organic tin compound (curing catalyst) and an organic carboxylic acid metal salt (curing modifier) is blended in the curing agent is It can be seen that this is an ideal sealing material that has good foamability and curability, has sufficient workable time, is excellent in durability, and has no fear of adverse effects on the environment or the human body.

  The two-component polyurethane sealant of the present invention is particularly advantageously used as a sealant in the fields of civil engineering / architecture, automobiles, and electric / electronics.

Claims (5)

(A) Base (I) comprising an isocyanate group-terminated prepolymer, (B) polyoxyalkylene ether and (C) organotin compound (curing catalyst) 0.1 to 6 parts by mass (provided that (B) polyoxy A curing agent (II) containing 100 parts by mass of an alkylene ether),
(D) Organic carboxylic acid metal salt (curing modifier) 0.2-9 parts by mass (however, (B) 100 parts by mass of polyoxyalkylene ether) is blended with curing agent (II). A two-component polyurethane sealing material. (D) The metal of the organic carboxylic acid metal salt is calcium, The two-component polyurethane sealing material according to claim 1. (D) The carboxylic acid of an organic carboxylic acid metal salt is octylic acid, The two-component polyurethane sealing material according to claim 1 or 2. (A) The number of average functional groups (f) defined by the following formula (1) of the base (I) composed of an isocyanate group-terminated prepolymer is 2.2 or more and 3.0 or less, Item 2. The two-component polyurethane sealing material according to any one of Items 1 to 3.

(C) The organic tin compound (curing catalyst) is a tetravalent organic tin compound, The two-component polyurethane-based sealing material according to any one of claims 1 to 4.