JP2531516B2 - Sealing material - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION (Industrial field of application) The present invention relates to seals in joints of structures, gaps of screw joints, window glass of automobiles, and fittings around sashes, and joints for concrete spantion, concrete. The present invention relates to a sealing material used for repairing cracked portions of the material and jointing of the sealing material.

(Prior Art) As a sealant to be applied to a joint portion of a conventional structure and a sealant used to repair the seal portion, for example, a silicone-based, polysulfide-based, polyurethane-based, modified silicone-based, acrylic urethane-based, epoxy-based solvent-free solvent is used. There are reaction effect type elastic sealing materials, acrylic type, SSB type and butyl rubber type emulsion type or solvent type sealing materials.

Further, as the non-curing type sealing material, there are butyl rubber type, silicone mastic type, glass putty and the like, and a molded butyl sealing material is also used as a fixed gasket.

(Problems to be solved by the invention) By the way, the conventionally used solventless reaction-curable elastic sealing material is separated from the interface when stress is concentrated on the adhesive surface and fatigue accumulates due to expansion and contraction over many years. Poor waterproofness due to the possibility of leaking water.

Further, the emulsion type or solvent type sealing material is liable to contract and crack during curing, and has poor elasticity after curing, and its followability is not good.

Further, since the non-curing type sealing material does not have elasticity, no stress is applied to the adhesive interface, and the interface peeling is small, but the followability is poor. If the sealing material does not have sufficient followability with respect to the adhered surface as described above, after the sealing material is applied to joints and the like, when the joints expand and contract due to aging and the like, cracks and gaps occur, and the sealing material is kept constant. It becomes impossible to maintain the airtightness and waterproofness.

Further, the regular butyl sealing material has a problem that the property changes severely with temperature, the adhesiveness decreases due to the temperature change, and the sealing material cannot be applied efficiently.

(Means for Solving the Problems) In order to solve the above problems, the adhesive sealing material which is the component A of the present invention has a viscosity at 25 ° C. of 500 to 500.
It contains 100 parts by weight of organopolysiloxane of 000 cst, 5 to 400 parts by weight of inorganic filler, and 0.1 to 20 parts by weight of polyisobutylene. It has excellent adhesion and followability to the adherend and changes in properties with temperature. It is improved so as to be small, and further, the waterproofness and airtightness of the structure and the like when it is filled in the joints and the like of the structure are improved, and the efficiency of the coating work is improved.

The organopolysiloxane contained in the adhesive sealing material which is the component A of the present invention has the following general formula: A siloxane bond having a skeleton represented by and having both terminal ends blocked with hydroxyl groups is used. Here, in the above formula, R ¹ and R ² are each a monovalent carbon atom such as a methyl group, an ethyl group, a propyl group, a phenyl group, or a trifluoropropyl group in which a part of these is substituted with a halogen atom. The same type (for example, dimethylpolysiloxane) composed of hydrogen groups or different types of groups. N is a positive integer representing the degree of polymerization and has a viscosity at 25 ° C of 500 to 500000 cst,
Preferably 3000 to 50000 cst is used. In this case, if the viscosity is lower than 500 cst, it is not possible to suppress the separation caused by further blending polyisobutylene with this organopolysiloxane, so a uniform composition may not be obtained, and if it exceeds 500000 cst, the kneading work Efficiency may decrease.

Next, an inorganic filler is added to improve the compatibility between the above-mentioned organopolysiloxane and polyisobutylene and to uniformly mix them. Examples of the inorganic filler include fumed silica, wet silica, calcium carbonate,
Talc, clay, kaolin, asbestos, glass fiber,
Alumina and the like can be used, and these can be used alone or as a mixture of two or more kinds. The blending amount of this inorganic filler can be appropriately selected so that the separation of the organopolysiloxane and the polyisobutylene can be suppressed, and the amount is too large to make stirring impossible. Depending on the type of filler, for example, when a fine substance such as fumed silica is used, it is preferably about 5 to 20 parts by weight with respect to 100 parts by weight of organopolysiloxane, and a coarse substance such as ground calcium carbonate. When used, it is preferably about 100 to 400 parts by weight.

Polyisobutylene is contained in order to give excellent adhesiveness and followability to the adhesive sealing material. And m is an integer of 10 or more and represents the degree of polymerization.

As a specific example of this polyisobutylene, the average molecular weight is about 4000 ~ 6000 at room temperature has a semi-liquid to peripheral rubber-like shape, Vistaneck LM-MS-LC (Exxon Chemical Co., trade name), Vistanec LM-MS-LC (trade name, manufactured by Exxon Chemical Co., Ltd.) and the like can be mentioned.

When these isobutylenes are mixed with the organopolysiloxane, the mixture is heated to about 100 to 120 ° C to reduce the viscosity until it becomes a liquid and stirred and mixed, and then the above fillers are further stirred and mixed, and the mixture is allowed to reach room temperature. On cooling, a rubber-like sticky substance is obtained which does not separate. Further, in this case, as polyisobutylene, in particular, NC7000 (manufactured by NOF CORPORATION, trade name) (about 10 parts by weight of polyisobutylene based on 100 parts by weight of low-viscosity polybutene oil is preheated and mixed at room temperature. If a viscous liquid) is used, the composition can be stirred and mixed at room temperature, and the workability can be further improved.

The amount of polyisobutylene blended is organopolysiloxane.
It is from 0.1 to 20 parts by weight, preferably from 5 to 20 parts by weight, based on 100 parts by weight, and when it is 0.1 parts by weight or less, excellent rubber-like tackiness cannot be obtained. Further, in this case, when 20 parts by weight or more of polyisobutylene is blended, stirring work of the composition becomes difficult, and the temperature dependency of the obtained adhesive sealing material becomes large, so that the shape change due to temperature becomes severe, Under temperature conditions, the viscosity of the adhesive sealing material becomes too low, which may hinder the coating operation, which is not preferable. When NC7000 is used as the polyisobutylene, it may be added in an amount of 1 to 200 parts by weight based on 100 parts by weight of the organopolysiloxane.

The above components are uniformly stirred and mixed by a kneader or a planetary mixer, which is a high torque stirrer, to adjust the adhesive sealing material. In addition, the adhesive sealing material of the present invention may be filled in, for example, a tube-shaped container or a cartridge and stored, and may be directly applied to an adherend, or may be directly applied to a joint of a structure with a spatula or a trowel. Alternatively, it is also possible to further increase the viscosity of the adhesive sealing material and then form it into a tape using an extruder to use it as a fixed gasket. The molded sealing material may be an extrusion molded product having a sponge inside or a roll molded product having a reinforcing material inside, in addition to the above extrusion molded product.

When the adhesive sealing material which is the component A of the present invention is applied to an adherend, the surface of the adhesive sealing material has adhesiveness, so that the adhesive sealing material migrates due to contact with another structure or the like, dust or the like. Are easily adsorbed and easily contaminated. Therefore, the following method must be used in order to make the surface of the adhesive sealing material after adhesion non-adhesive.

After applying the adhesive sealing material to the adherend such as a joint, 100 parts by weight of an organosilicon compound having three or more hydrolyzable reactive groups in one molecule and a silanol condensation catalyst are formed on the surface of the adhesive sealing material. The surface is detackified by applying 1 to 20 parts by weight of the crosslinking agent composition which is the component B of the present invention to the surface.

In this method, 3 hydrolyzable reactive groups are included in one molecule.
The organosilicon compound having more than one acts as a crosslinking agent and a storage stabilizer for the organopolysiloxane having a hydrolysis-reactive hydroxyl group. Examples of the hydrolyzable reactive group constituting the organic silicon compound here include an alkoxy group, an aminoxy group, an alkenyloxy group, an acetoxy group, an acyloxy group, a heximate group, and an isocyanate group. Specifically, for example, MeSi (OMe) ₃ , ViSi (OMe) ₃ , Si (OMe) ₄ , PhSi (OMe) ₃ , MeSi (OEt) ₃ , Si (OEt) ₄ , MeSi (OAc) ₃ , MeSi (ONHEt) ₃ , MeSi ( NMe) ₃ , MeSi (NCo) ₃ , Etc. can be mentioned. In the above formula, Me is a methyl group,
Et represents an ethyl group, Ph represents a phenyl group, Ac represents an acetyl group, and Vi represents a vinyl group.

The silanol condensation catalyst used in this method also acts as a condensation reaction accelerating catalyst between the terminal hydrolysis-reactive silanol groups of the organopolysiloxane and the hydrolysis-reactive polyfunctional organosilicon compound contained in the crosslinking agent composition. By mixing an appropriate amount, the condensation reaction rate can be increased. Therefore, when the cross-linking agent composition of the component B is applied on the surface of the tacky sealing material which is the component A, the surface layer portion of the tacky sealing material is cured by the cross-linking agent composition, and the non-tacky rubber-like film is formed. Is formed. The silanol condensation catalyst is used in the range of 0 to 20 parts by weight with respect to 100 parts by weight of the hydrolyzable organosilicon compound. In this case,
If the blending ratio is low, the curing speed may be too low,
If it is more than 20 parts by weight, the curing rate will be too high to obtain a sufficient pot life during use, and the physical properties of the sealing material may be deteriorated. Further, in this case, when the hydrolyzable reactive group of the organosilicon compound is a strongly active group such as an amino group or an isocyanate group, the reaction proceeds sufficiently even without using the silanol condensation catalyst described above. In such a case, the silanol condensation catalyst may not be used.

Examples of this silanol condensation catalyst include dibutyltin dilaurate, dibutyltin acetate, dibutyltin dioctoate, organotin compounds such as dibutyltin oxide, lead ethyl octoate, titanium naphthenate, metal salts of organic carboxylic acids such as zinc stearate, and laurylamine. , Amines such as di-n-butylamine and hexylamine, and compounds such as organic titanate esters such as tetraisopropoxy titanate and tetraisobutoxy titanate, which are used alone or as a mixture of two or more kinds. be able to.

The crosslinker composition obtained by silanol condensation catalyst with an organosilicon compound having 3 or more hydrolyzable reactive groups in one molecule as described above is applied to the surface of an adhesive sealing material having rubber elasticity. To contact the surface of the adhesive sealing material, and form a non-adhesive rubbery film only on the surface of the adhesive sealing material to protect the surface of the adhesive sealing material.

(Example) An organopolysiloxane, a filler, and polyisobutylene were mixed in the mixing ratio shown in Table 1 to obtain an adhesive sealing material of Example 1. Silicone oils 1 and 2 in Table 1 are the following dimethylpolysiloxanes, respectively.

Silicone oil 1; Viscosity at 25 ° C is 5000 cst, both ends blocked with methyl groups.

Silicone oil 2; one having water distribution groups at both ends with a viscosity of 5000 cst at 25 ° C.

Silicone oil 3; viscosity at 25 ° C is 20000 cst, both ends blocked with methyl groups.

The adhesive sealant of Example 1 was prepared by using a double arm type kneader and polyisobutylene NC- in silicone oil at room temperature.
After adding 7000, the filler was added and the mixture was stirred for 1 hour for adjustment.

Comparative Examples 1-3 As shown in Table 2, Comparative Example 1 does not contain polyisobutylene, Comparative Example contains 0.2 parts by weight of NC7000, and Comparative Example 3 contains 30 parts by weight of LM-MS-LC. Example 3 except that
The sealing material was adjusted in the same manner as in.

The NC7000 used in Comparative Example 2 contains 10 parts by weight of polyisobutylene, when the total amount is 100 parts by weight.

Comparative Examples 4 to 5 A commercially available oily caulking material (manufactured by Sanyo Kogyo Co., Ltd., Three Coking C-300) is used as Comparative Example 4, and a commercially available silicone mastic type sealing material (Sealing 79, Shinetsu Silicone Co., Ltd.) is used as Comparative Example 5. Was used.

Next, with respect to the sealing materials obtained in Example 1 and Comparative Examples 1 to 5, the penetration, the adhesive force, and the followability were respectively 0 ° C. and
It was measured at 25 ° C and 50 ° C, and the weather resistance was observed with a sunshine weather meter. The results of these measurements and observations are shown in Tables 1 and 2.

(1) Measuring the degree of needle penetration With an applied load of 100 g, the needle penetration for 5 seconds at 0 ° C, 25
Measured to 0.1 mm at ℃ and 50 ℃.

(2) Measurement of adhesive strength 1.0mm x 51mm x 100mm test piece made of aluminum is coated with a sealing material to a thickness of 0.2mm on one side, and the surface is applied.
Press the 0.2 mm × 25 mm × 120 mm polyethylene film so that it does not contain air bubbles and bring it into close contact.
Based on SZ 0237, it was attached to a mounting jig used in the 90-degree peeling method of adhesive strength measurement, and this was pulled by a tensile strength tester at a speed of 300 mm / min, and the stress was measured.

(3) Speed of followability In accordance with JIS A 5758, a polyethylene foam is used as a backup material in a H-shaped block to fill the sealing material, and this is pulled by a tensile strength tester at a speed of 300 mm / min. The elongation at break was measured.

(4) Observation of weather resistance A concrete block with a size of 12 x 100 mm and a depth of 12 m
A groove of m was dug, the groove was filled with a sealing material, and exposed to a sunshine weather meter for 1000 hours, 1500 hours, and 2000 hours, and the surface state of the sealing material was observed at each time.

As shown in Table 1, the adhesive sealing material of Example 1 has a high penetration regardless of the temperature and has a wide temperature range in comparison with other sealing materials in a liquid state in spite of the liquid state. It has high adhesiveness and excellent followability, and
No abnormalities were observed in the observation of the sunshine weather meter from 1000 hours to 2000 hours.

Therefore, the adhesive seal ring material of Example 1 is excellent in flexibility, does not change in shape due to temperature change, and is excellent in workability.
It was confirmed that it has excellent weather resistance as well as excellent airtightness and waterproofness.

On the other hand, it was confirmed that the composition of Comparative Example 1 containing no polyisobutylene and the composition of Comparative Example 2 containing a small amount of polyisobutylene (0.2 × 0.1 part by weight) were significantly inferior in adhesive strength and followability. Further, the composition of Comparative Example 3 containing a large amount of polyisobutylene in an amount exceeding the compounding ratio in the present invention (30 parts by weight), the penetration, the adhesive force and the followability varied depending on the temperature, and the followability was Inferior and 2000 in weather resistance test
Generation of cracks was confirmed over time. Further, with respect to the commercially available caulking material of Comparative Example 4, it was confirmed that the temperature dependency of the penetration was very high, the tackiness was very low, the followability was low, and the temperature dependency was high, and it was 1000 to 2000 in the weather resistance test.
The occurrence of cracks was confirmed by Hr. Furthermore, it was confirmed that the mastic type sealing material of Comparative Example 5 had poor penetration and tackiness.

Examples 2 to 5 The sealing material obtained in Example 1 was filled in the concrete grooves used for the weather resistance test, and the surface of the sealing material contained an organosilicon compound having three hydrolyzable reactive groups in one molecule and silanol. After the cross-linking agent compositions of Examples 2 to 5 in which the condensation catalysts were mixed in the mixing ratios shown in Table 2 were applied respectively, they were dried by touch and then left at room temperature for 7 days to obtain a surface-hardened layer. The thickness was measured. The second measurement result of the thickness of the surface hardened layer
Shown in the table.

Comparative Examples 6 to 7 As shown in Table 2, after filling the concrete material used in the weather resistance test with the sealing material obtained in Example 1, Comparative Example 6 was used.
As a composition comprising an organosilicon compound having two hydrolyzable reaction groups in one molecule instead of three and a silanol condensation catalyst, as Comparative Example 7 having three hydrolyzable reaction groups without adding a silanol condensation catalyst Only organosilicon compounds,
After each coating, each of them was dried by touching with the finger, and allowed to stand at room temperature for 7 days, and the thickness of the surface-cured layer was measured. Table 2 shows the measurement results of the thickness of the surface-hardened layer.

As shown in Table 2, 100 parts by weight of an organosilicon compound having 3 or more hydrolyzable reactive groups in one molecule on the surface of the sealing material obtained in Example 1 and 2 parts by weight of a silanol condensation reaction catalyst are crosslinked. Examples 2 to 5 formed by applying the agent composition
It was confirmed that the sealing material of (1) cures the surface layer portion of the adhesive layer very quickly and forms a non-adhesive cured layer on the surface layer portion.

On the other hand, in the case of blending an organosilicon compound having two hydrolyzable reactive groups in one molecule of Comparative Example 6 and as in Comparative Example 7, it has three hydrolyzable reactive groups without adding a silanol condensation catalyst. It was confirmed that even when only the organosilicon compound was applied to the surface of the adhesive sealing material obtained in Example 1, the surface of the sealing material was not sufficiently cured and a non-adhesive film was not formed.

(Effect of the invention) As described above, in the sealing material of the present invention, A
The adhesive sealant of the component is excellent in adhesive strength and followability,
In addition, since the property change due to temperature is extremely small, it adheres well to the adherend when it is filled into joints of structures, etc., and it also follows the expansion and contraction of the adherend due to changes in joints over time, etc. The waterproofness and waterproofness can be maintained. Furthermore, since the adhesive sealing material has excellent rubber-like adhesiveness over a wide temperature range, it maintains a constant viscosity even under working temperature conditions and improves the work efficiency of coating work.

Further, the cross-linking composition of the component B is applied to the surface of the adhesive sealing material applied to the structure or the like to form a non-adhesive rubber-like film, and the surface layer of the sealing material of the present invention is non-adhesive. By this, the contamination of the surface layer portion can be suppressed and the migration of the sealing material can be prevented.

Claims (1)

(57) [Claims] 1. (A) Viscosity at 25 ° C. is 500 to 50,000 cst
And an adhesive sealant containing 100 parts by weight of organopolysiloxane having both ends blocked by hydroxyl groups, 5 to 400 parts by weight of an inorganic filler, and 0.1 to 20 parts by weight of polyisobutylene, (B) in one molecule A cross-linking agent composition consisting of 100 parts by weight of an organosilicon compound having 3 or more hydrolyzable reactive groups and 20 parts by weight or less of a silanol condensation catalyst. A sealing material, which comprises applying a crosslinkable composition of component B to make the surface non-tacky.