JPH08311330A - Room temperature-curable composition - Google Patents

Abstract

PURPOSE: To obtain the subject composition having excellent durability to inva sion of rain water or temperature variation, etc., after curing, comprising a specific proportions of an organopolymer having a reactive silicon, a curing catalyst and cement. CONSTITUTION: This composition comprises (A) 100 pts.wt. of an organopolymer containing a reactive silicon, (B) 0.5-5 pts.wt. of a curing catalyst (e.g.; alkyltitanate) and (C) 10-150 pts.wt. of cement (e.g.; dolomite.plaster). The molecular weight of the component A is preferably 500-50000. In the case where the objective composition is preferably a liquid from the viewpoint of handling, the molecular weight of the component A is preferably 1000-20000. The composition may be blended as necessary with a dehydrating agent such as vinyl methoxysilane or an adhesion-imparting agent such as γ-aminopropyl triethoxysilane. Furthermore, an inorganic granular material such ass silica or an inorganic fibrous material such as sepiolite may be used for the purpose of reinforcing or imparting a thixotropy.

Description

Detailed Description of the Invention

[0001]

FIELD OF THE INVENTION This invention relates to room temperature curable compositions.

[0002]

2. Description of the Related Art An organic polymer containing a reactive silicon group reacts with atmospheric humidity at room temperature to be cured into a rubber-like substance having excellent flexibility and impact resistance. Widely used as materials, elastic adhesives, etc. In a sealing work for protecting joints of a building material with a sealing material, a spatula finish is performed after the sealing material is filled and before the sealing material is cured in order to smooth the surface. In this case, since the spatula finish becomes difficult when the sealing material hardens, the slower the sealing material cures, the better the workability. On the other hand, on the other hand, the point that it can respond to the movement of the joint and the contamination of the surface by the adhesion of dust Therefore, it is desired that the sealing material be cured as quickly as possible.

JP-A-3-294355 discloses that a room-temperature-curable composition comprising a polyalkylene ether, an organic silicon compound, a filler and a silanol catalyst is useful as a sealing material, an elastic adhesive or the like. Has been done.

When such a room temperature curable composition is used as a sealing material, an elastic adhesive, etc., it is exposed to the outdoor environment even after curing, and the adhesive strength is lowered due to the infiltration of rainwater, temperature change, etc. However, the durability was not sufficient.

[0005]

SUMMARY OF THE INVENTION In view of the above, it is an object of the present invention to provide a room temperature curable composition having good durability against infiltration of rainwater after curing, temperature change and the like.

[0006]

DISCLOSURE OF THE INVENTION The gist of the present invention is to provide a room temperature curable composition containing an organic polymer 1 containing a reactive silicon group.
It is composed of 100 parts by weight, 0.5 to 5 parts by weight of a curing catalyst, and 10 to 150 parts by weight of cement.

The organic polymer containing a reactive silicon group used in the present invention is not particularly limited, and for example, the following general formula --RO-- (wherein R is a carbon number of 2 to 4) is used. A divalent alkylene group), which is a graft unit obtained by polymerizing a vinyl monomer such as acrylate ester, styrene, acrylonitrile or vinyl acetate in the presence of a polyether such as polypropylene oxide. Polymers or copolymers such as polymers; polyacrylic acid alkyl ester or acrylic acid alkyl ester containing 50% or more of acrylic acid alkyl ester and vinyl acetate,
Examples thereof include copolymers with acrylonitrile, styrene, ethylene and the like. These may be used alone or in combination of two or more.

In the present specification, the reactive silicon means a silicon atom-containing group to which a hydroxyl group or a hydrolyzable group is bonded and which can form a siloxane bond by a silanol condensation reaction. The hydrolyzable group is not particularly limited, and examples thereof include alkoxy groups having mild reactivity such as methoxy group and ethoxy group.

The molecular weight of the organic polymer having a reactive silicon group is preferably 500 to 50,000. When the room temperature curable composition is preferably liquid in terms of handling, the molecular weight is preferably 1,000 to 20,000.

The curing catalyst used in the present invention is not particularly limited, and examples thereof include alkyl titanates, organosilicon titanates, tin octylates, dibutyltin dilaurates, dibutyltin malates, dibutyltin phthalates, and other carboxylic acids. Examples thereof include acid metal salts; amine salts such as dibutylamine-2-ethylhexoate; and other known silanol condensation catalysts such as acidic catalysts and basic catalysts. These may be used alone or in combination of two or more.

The amount of the curing catalyst added is 0.5 with respect to 100 parts by weight of the organic polymer containing a reactive silicon group.
~ 5 parts by weight. If it is less than 0.5 parts by weight, a sufficient effect of accelerating the curing cannot be obtained, and if it exceeds 5 parts by weight, the catalytic effect is not improved and a diluting action is exerted, so that it is limited to the above range.

The cement used in the present invention is not particularly limited, and examples thereof include air-hardening cements such as dolomite plaster, keens cement and magnesia cement;
Roman cement, natural cement, Portland cement, alumina cement, blast furnace cement, silica cement, fly ash cement, masonry cement, expansive cement, hydraulic cement such as colored cement; special cement such as acid resistant cement Can be mentioned. These may be used alone or in combination of two or more.

The cement is added in an amount of 10 to 100 parts by weight of the organic polymer containing the reactive silicon group.
It is 150 parts by weight. If the amount is less than 10 parts by weight, water that permeates into the room temperature curable composition from the adherend and the outside cannot be sufficiently absorbed, and therefore, sufficient effect for improving the adhesion durability cannot be obtained. When it exceeds, the cement is hardened by the absorbed water, the flexibility of the room temperature curable composition is impaired, and the rubber elasticity which is a characteristic of the sealing material, the elastic adhesive and the like is lost, so the content is limited to the above range.

If necessary, the room temperature curable composition of the present invention may contain a dehydrating agent, an adhesiveness-imparting agent or the like.

The dehydrating agent is not particularly limited, and examples thereof include vinylsilanes such as vinyltrimethoxysilane; orthoformate ester and the like. The organic polymer containing a reactive silicon group which is an essential component of the room temperature curable composition of the present invention, the curing reaction proceeds due to moisture,
A dehydrating agent is preferably added in order to prevent the compound from gelling before use due to a trace amount of water.

The adhesiveness imparting agent is not particularly limited, and examples thereof include aminosilanes such as (2-aminoethyl) aminopropyltrimethoxysilane and γ-aminopropyltriethoxysilane; γ-mercaptopropyltrimethoxysilane and the like. Mercaptosilanes; epoxysilanes such as γ-glycidoxypropyltrimethoxysilane and the like.

For the purpose of reinforcing and imparting thixotropy to the room temperature curable composition of the present invention, for example, calcium carbonate, magnesium carbonate, hydrous silicic acid, calcium silicate, silica,
Inorganic particles such as titanium dioxide, clay, talc; asbestos, wollastonite, sepiolite, slag fiber,
Inorganic fibrous substances such as zonotolite, potassium titanate, elestadite, gypsum fibers; hydrogenated castor oil, organic thixotropic agents such as fatty acid amide wax, inorganic minerals such as mica, kaolin and bentonite; glass balun, fly ash balun, silas balun You may use hollow filler etc.

In addition to the above, a plasticizer such as a phthalate ester; an antiaging agent such as a hindered amine type or a hindered phenol type; a pigment such as carbon black; an ultraviolet absorber or the like may be added.

[0019]

The present invention will be described in more detail below with reference to examples, but the present invention is not limited to these examples.

Preparation of Room Temperature Curable Compositions For Examples 1 to 5 and Comparative Examples 1 to 3, the respective raw materials were weighed at the weight ratios shown in Table 1 and uniformly kneaded in a sealed mixing stirrer to obtain room temperature curable compositions. The thing was prepared. The following evaluations were performed on the compositions of Examples 1 to 5 and Comparative Examples 1 to 3 prepared as described above.

Adhesiveness: According to JIS K 6852 (compressive shear adhesive strength test method for adhesives), using a porcelain mosaic tile and mortar as adherends, the room temperature curable composition prepared by the above-mentioned method was used. After coating so as to have a rate of 5 kg / m ² (bonding area 25 mm × 25 mm), both adherends were bonded together. This test body was aged in a constant temperature and humidity room at a temperature of 23 ° C. and a humidity of 65% for 14 days and then subjected to a compression shear test. Further, the cured test body was immersed in hot water at 90 ° C. for 1 month and vacuum dried at a temperature of 60 ° C. for 8 hours, and then the same compression shear test was performed.

Physical Properties of Cured Material The prepared room temperature curable composition was spread into a sheet having a thickness of 2 mm, cured and cured in a constant temperature and humidity room at a temperature of 23 ° C. and a humidity of 65% for 14 days, and then JIS K 6301 was used. According to (Physical test method for vulcanized rubber), tensile strength and elongation were measured with a No. 3 dumbbell shape. Moreover, the cured product was immersed in hot water at 90 ° C. for 1 month and vacuum-dried at a temperature of 60 ° C. for 8 hours, and then the tensile strength and the elongation were measured in the same manner. The results are shown in Table 1.

The contents of the raw materials of Examples 1 to 5 and Comparative Examples 1 to 3 are as follows. (1) Organic polymer containing reactive silicon group; (Kanefuchi Chemical Industry Co., Ltd., Cyryl SAT200) (2) Organic polymer containing reactive silicon group; (Kanebuchi Chemical Industry Co., Ltd., Cyryl (MAX447) (3) Colloidal calcium carbonate; (manufactured by Shiraishi Industry Co., Ltd., CC
R) (4) Hydrophobic silica; (Aerosil R202 manufactured by Nippon Aerosil Co., Ltd.) (5) Portland cement; (Chichibu Onoda Cement Co., Ltd.) (6) Alumina cement; (Asahi Glass Co., Ltd.) (7) γ- (2- (Aminoethyl) aminopropyltrimethoxysilane; (KBM603, manufactured by Shin-Etsu Silicone Co., Ltd.) (8) Vinyltrimethoxysilane; (KBM1003, manufactured by Shin-Etsu Silicone Co., Ltd.) (9) Curing catalyst for organic polymer containing reactive silicon group Dibutyltin diacetylacetonate (Nitostane U-220 manufactured by Nitto Kasei Co., Ltd.)

As is clear from Table 1, the room temperature curable compositions of Examples 1 to 5 of the present invention show good adhesiveness and adhesion durability, and the cured products have flexibility. On the other hand, the room temperature curable compositions of Comparative Examples 1 to 3 could not satisfy either or both of these physical properties.

[0025]

[Table 1]

[0026]

EFFECTS OF THE INVENTION Since the room temperature curable composition of the present invention has the above-mentioned constitution, it is possible to obtain a room temperature curable composition having good durability against infiltration of rainwater after curing, temperature change and the like. .

Claims (1)

[Claims] 1. An organic polymer 1 containing a reactive silicon group.
A room temperature curable composition comprising 00 parts by weight, 0.5 to 5 parts by weight of a curing catalyst, and 10 to 150 parts by weight of cement.