JPH05311063A - Sealant composition - Google Patents

Abstract

PURPOSE:To obtain a sealant compsn. excellent in fast-setting properties by blending a polyether polymer having cross-linkable hydrolyzable silyl groups in the molecular terminals thereof with a given amt. of a specific titanium chelate compd. CONSTITUTION:A polymer having a polyether chain essentially as the main chain and cross-linkable hydrolyzable silyl groups in the molecular terminals thereof is prepd., e.g. by reacting an oxyalkylene polymer having etherified allylolefin groups in the molecular terminals thereof with a hydrosilicon compd. in the presence of a transition metal of the Group VIII. 100 pts.wt. polymer thus prepd. is blended with 0.1-10 pts.wt. titanium chelate compd. of formula I (R<1> and R<2> are each 1-10C alkyl; and R<3> and R<4> are each 1-8C alkyl), e.g. a compd. of formula II or III, as a curing catalyst to prepare a sealant compsn. This compsn. is low in toxicity and quickly curable into a rubbery material upon the reaction with moisture in air, and hence may suitably be used as a sealant.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a sealant composition which reacts with atmospheric moisture to cure into a rubber, and more particularly,
The present invention relates to a sealing material composition having excellent quick-hardening property.

[0002]

2. Description of the Related Art As a polymer which reacts with moisture in the atmosphere and hardens into a rubber, for example, JP-A-50-156599 is known.
In the publication, an oxyalkylene polymer having an ether type allyl olefin group at the terminal is represented by the general formula (II) in the presence of a Group VIII transition metal.

[0003]

[Chemical 2]

(In the formula, R ⁵ is a group selected from a monovalent hydrocarbon group and a halogenated monovalent hydrocarbon group, a
Is an integer of 0, 1 or 2, X is an atom or a group selected from a halogen atom, an alkoxy group, an acyloxy group and a ketoximate group) and is obtained by reacting with a hydrosilicon compound. Polyethers having silyl groups are disclosed.

In order to cure such a polymer with moisture in the atmosphere, a curing catalyst such as a metal salt is necessary because the curing is slow. For example, a catalyst such as dibutyltin dilaurate or dibutyltin diacetate is used as the catalyst. Dialkyltin fatty acid salt compounds, titanate compounds such as tetra-n-butyl titanate, amine compounds and the like are used. However, since titanate compounds, dialkyltin straight-chain fatty acid salt compounds and amine compounds generally have low catalytic activity, the use of these compounds slows the curing speed of the polymer and thus cannot be used for sealing materials and the like. .

[0006]

SUMMARY OF THE INVENTION The present invention has been made in view of the above drawbacks, and its object is to improve the curing rate of a polymer having a crosslinkable hydrolyzable silyl group at the terminal.
It is an object of the present invention to provide a sealing material composition which has been raised to a level usable for applications such as a sealing material.

[0007]

The sealant composition of the present invention comprises a polymer (a) 1 whose main chain is essentially a polyether and which has a crosslinkable hydrolyzable silyl group at its terminal.
00 parts by weight and 0.1 to 10 parts by weight of the titanium chelate compound (b) represented by the general formula (I) are contained, whereby the above object is achieved.

The present invention will be described in detail below. The polymer (a) used in the present invention has a main chain essentially of polyether and has a crosslinkable hydrolyzable silyl group at the terminal, and for example, an ether type allyl olefin group at the terminal. An oxyalkylene polymer having
Examples thereof include those obtained by reacting with a hydrosilicon compound represented by the general formula (I) in the presence of a Group II transition metal.

[0009]

[Chemical 3]

In the formula, R ⁵ is a group selected from a monovalent hydrocarbon group and a halogenated monovalent hydrocarbon group, and a is
An integer of 0, 1 or 2 and X each represent an atom or a group selected from a halogen atom, an alkoxy group, an acyloxy group and a ketoximate group.

As the above-mentioned polymer (a), a polymer whose main chain is polyoxypropylene is particularly preferable from the viewpoint of physical properties of a cured product, and a polymer whose hydrolyzable silyl group is an alkoxysilyl group is more preferable.

If the molecular weight of the polymer (a) is small, the elongation of the cured product will be insufficient, and if it is large, the viscosity will be too high, and the workability of the composition will be deteriorated. The range of 1,000 to 30,000 is preferable.

Organotin compounds such as dibutyltin dilaurate, dibutyltin diacetate, dibutyltin phthalate, dibutyltin diacetylacetonate, and dibutyltin maleate have been used as a curing catalyst for the above polyethers. The compounds are toxic, have relatively low catalytic activity, and must be used with cocatalysts such as amines.
A practical curing rate as a sealing material could not be obtained.

Therefore, in the present invention, by using the titanium chelate compound represented by the general formula (I) as a curing catalyst, a sealing material having relatively low toxicity and excellent curing characteristics can be obtained.

[0015]

[Chemical 4]

In the formula, R ¹ and R ² represent an alkyl group having 1 to 10 carbon atoms, and R ³ and R ⁴ represent an alkyl group having 1 to 8 carbon atoms.

Examples of the titanium chelate compound represented by the general formula (I) include the following compounds (III) to (IX).

[0018]

[Chemical 5]

[0019]

[Chemical 6]

[0020]

[Chemical 7]

[0021]

[Chemical 8]

[0022]

[Chemical 9]

[0023]

[Chemical 10]

[0024]

[Chemical 11]

In the present invention, when the compounding amount of the titanium chelate compound (b) is small, the curing rate is low,
If the amount is too large, the physical properties of the cured product are remarkably deteriorated. Therefore, 0.1 to 10 parts by weight of the titanium chelate compound (b) is added to 100 parts by weight of the polymer (a).

In the sealing material composition of the present invention, various fillers can be used for the purpose of modification, and examples thereof include calcium carbonate, magnesium carbonate, hydrous silicic acid, silicic acid anhydride, calcium silicate, silica and dioxide. One or a mixture of two or more of titanium, clay, talc, carbon black and the like may be added.

Further, a plasticizer may be added in order to enhance the elongation performance of the cured product of the sealant composition and to reduce the modulus. Examples of such plasticizers include phosphates such as tributyl phosphate and tricresyl phosphate; phthalates such as dioctyl phthalate; aliphatic monobasic esters such as glycerin monooleate; dibutyl adipate and dioctyl adipate. Aliphatic dibasic acid esters and the like can be used, and one kind or two or more kinds thereof can be used.

A pigment, an ultraviolet absorber, an antioxidant, a silane coupling agent and the like may be added to the composition of the present invention, if necessary.

[0029]

EXAMPLES The advantages of the present invention will be clarified by comparing the examples of the present invention with the comparative examples.

(Examples 1 and 2 and Comparative Examples 1 to 3) 1) Preparation of Sealing Material Composition As a polymer (a) whose main chain is essentially polyether and which has a hydrolyzable silyl group at the terminal. , Using "Cyryl 5A03" (molecular weight: 8500) manufactured by Kanebuchi Chemical Co.,
The predetermined amounts of the components shown in Table 1 were blended by the following method. The blending method of each component is to uniformly knead the polymer (a), dioctyl phthalate as a plasticizer, and calcium carbonate and titanium oxide that have been pre-dried at 120 ° C. for 2 hours in a sealed mixer, and further mix the remaining components. In addition, the mixture was kneaded uniformly to obtain a sealing material composition.

2) Measurement of physical properties of sealant composition (1) Tack-free time Measurement was carried out at 23 ° C. and 65% RH in accordance with JIS A5758, and the results are shown in Table 1.

(2) Tensile Strength of Cured Product A sheet having a thickness of 2 mm was prepared from the sealing material composition prepared in 1) and aged at 23 ° C. and 65% RH for 1 week, and then JIS K6301 (Dumbbell No. 3, Tensile speed 50
mm / min) and the results are shown in Table 1.
It was shown to.

[0033]

[Table 1]

[0034]

According to the present invention, by adding a titanium chelate compound to a base resin of a polymer whose main chain is essentially a polyether and which has a crosslinkable hydrolyzable silyl group at its terminal, Provided is a sealant composition having a curing rate increased to a level at which it can be used for applications such as a sealant.

Claims (1)

[Claims] 1. A titanium chelate compound represented by the general formula (I), wherein 100 parts by weight of a polymer (a) whose main chain is essentially a polyether, and which has a crosslinkable hydrolyzable silyl group at its terminal. (B) A sealant composition comprising 0.1 to 10 parts by weight. [Chemical 1] (In the formula, R ¹ and R ² are alkyl groups having 1 to 10 carbon atoms,
R ³ and R ⁴ each represent an alkyl group having 1 to 8 carbon atoms. )