JP2612796B2 - Polysulfide composition - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

The present invention relates to a polysulfide composition for a sealing material. More specifically, the present invention relates to a polysulfide composition that can prevent the occurrence of crater-like avatars without being greatly affected by application conditions when curing a sealing material.

[0002]

2. Description of the Related Art Conventionally, a two-pack type polysulfide-based sealing material has been used as a sealing material for building and industrial use because it has excellent weather resistance and durability and also adheres well to various building members by using a primer. Widely used. However, this two-pack type polysulfide-based sealing material is used for joints that are not painted because the stains adhere to the joint surface due to the migration of the plasticizer even if the paint is applied to the joints after casting on the joints and the joints become dirty. Often. In addition, when the two liquids are mixed and poured into the joint, air bubbles are mixed in, and the sealing material exposes the joint, so that the sealing material is cast into the joint, and as the curing of the sealing material proceeds, a crater-like avatar is formed on the surface. It has the disadvantage that it occurs and, when viewed, significantly impairs aesthetics. In order to solve this problem, conventionally, when mixing the above-mentioned base and curing agent, a special construction method such as performing vacuum defoaming and minimizing embracing foam has been performed. However, it was difficult to completely eliminate crater-like avatars by this method. Or, to improve this difficulty,
Research and development of modification of the surface of polysulfide-based sealing materials have been carried out, and for example, Japanese Patent Application Laid-Open No. 64-159 discloses a method in which phenylhydrazine and sodium perborate are added to and mixed with the sealing material. In the case of phenylhydrazine, the effect is exhibited at a temperature of 20 ° C. or higher, but on the other hand, the effect is insufficient at temperatures lower than that, and in the case of sodium perborate, it is easily affected by humidity. However, under high humidity conditions, the effect is insufficient.

[0003]

SUMMARY OF THE INVENTION The present invention is an improvement on the above-mentioned problems of the conventional polysulfide-based sealing material, and the object thereof is to implement a special construction method such as vacuum defoaming. Prevents the occurrence of crater-like avatars that occur during curing regardless of the application conditions such as temperature and humidity, and does not impair the appearance or appearance of the surface, and possesses the excellent properties of polysulfide-based sealing materials To provide a polysulfide composition.

[0004]

The polysulfide composition of the present invention comprises a base containing liquid polysulfide as a main component and a curing agent containing lead dioxide as a main component. And at least one material selected from zeolite and activated alumina is contained in an amount of 0.2 to 36.0% by weight based on the liquid polysulfide. When the joint is filled with the polysulfide composition, a special construction method such as vacuum defoaming is not required, and the construction can be performed by a usual method to be a sealing material for preventing generation of crater-like avatars.

Hereinafter, the configuration of the present invention will be described in detail. (1) Liquid polysulfide A polymer having a reactive mercapto group at the terminal. This compound is represented by the following general formula, and the average value of _x is 1.5 to 2.5.
And _n is 2-45. R is a divalent aliphatic group, and an oxygen atom can be interposed between carbon atoms. ).

[0006]

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R is, for example, an ethylene group, a propylene group,
Butylene group, diethyleneoxy group, dipropyleneoxy group, dibutyleneoxy group, diethylenemethylenedioxy group, dipropylenemethylenedioxy group, dibutylenemethylenedioxy group and the like. Further, the molecular weight of the liquid polysulfide polymer is preferably 200 to 20,000, more preferably 500 to 8,000. As a method for producing a sealing material for this liquid polysulfide,
Various additives such as a filler, a plasticizer, a colorant, a reaction modifier, and an adhesion-imparting agent are blended. Fillers include, for example, reinforcing fillers such as fumed silica, precipitated silica, non-reinforcing fillers such as heavy calcium carbonate, light calcium carbonate, and microballoons. Examples of the plasticizer include phthalate esters such as butylbenzyl phthalate,
Phosphate esters such as tricresyl phosphate and chlorinated paraffins having a chlorination rate of 50% or more are available. Examples of the coloring agent include carbon black and titanium oxide.
In addition, a reaction modifier such as stearic acid and an adhesion-imparting agent such as a phenol resin can be added.

(2) Lead dioxide A curing agent for the above liquid polysulfide polymer. This lead dioxide is usually not kneaded as a powder, but is made into a paste using an appropriate diluent, for example, chlorinated paraffin, and is compounded. At that time, stearic acid or the like, which is a reaction modifier, can be blended. The compounding amount is liquid polysulfide 10
It is used in the range of 2 to 30 parts by weight per 0 parts by weight. If it is less than 2 parts by weight, it may not be cured sufficiently, and may not satisfy the performance required for the rubber-like elastic body. On the other hand, when the amount exceeds 30 parts by weight, the cured physical properties are reduced, which is economically problematic, and thus is not preferred.

[0009] (3) the matrix modifier (zeolites, activated alumina) as the matrix modifier for use in the present invention such as zeolites _{(MeO · Al 2 O 3 ·} mSiO 2 · n H 2 O, Me:
Examples of the metal ions include natural zeolites and synthetic zeolites. Among these, the particle size is 0.5 to 15 μm.
m, and a synthetic zeolite having an effective pore diameter of 3 to 10 ° is most preferable. The activated alumina (composition mainly composed of γ-alumina) preferably has a particle diameter of 0.2 to 200 μm (preferably 0.2 to 10 μm). It is preferable that these base improvers themselves have a sufficient dehydration mechanism and have the necessary conditions, or are substantially porous, or can be used in combination with a porous inorganic filler or the like. Those that act on the transfer and dispersion of bubbles are preferred. Although base and curing agent composed mainly of lead dioxide as a main component a liquid polysulfide is usually stored separately, the zeolite is a foundation improvement agent of the third component, activated alumina base, curing agent Any of them can be blended. Further, it can be added when the base material and the curing curing agent are blended. Further, the amount used is in the range of 0.2 to 36.0 parts by weight, preferably 1.5 to 19.5 parts by weight, based on 100 parts by weight of the liquid polysulfide.
If the amount is less than 0.2 parts by weight, it is not possible to prevent the occurrence of avatar-like craters. Is easily foamed and is disadvantageous economically.

[0010]

According to the present invention, zeolite,
Only when at least one material improving agent selected from activated alumina is blended into a sealing material containing liquid polysulfide as a main component, it works to prevent the generation of crater-like avatars. Furthermore, according to the polysulfide composition of the present invention, the effect of preventing avatar-like craters is not largely affected by construction conditions such as temperature and humidity. In addition, the anti-crater effect is zeolite,
By the dehydration function that activated alumina has as an attribute, the water in the sealing material, and the water generated by the reaction between liquid polysulfide and lead dioxide are adsorbed, and at the same time, the dispersion of bubbles in the sealing material and the suppression of migration can be suppressed. It is considered to be expressed. In particular, whether the base improver itself has sufficient or necessary porosity in conjunction with the dehydration function,
Alternatively, when a porous filler or the like can be used in combination, the porosity allows moisture to be adsorbed in the pores in a closed state, and the synergistic effect of the dehydration function and the porosity further enhances the moisture adsorbing power. It works so that the contact between the moisture and the bubbles can be suppressed.

[0011]

As described above, according to the present invention, excellent workability, rubber elasticity, adhesiveness, weather resistance, etc. of the polysulfide-based sealing material are not affected by the working conditions such as temperature and humidity, and the use conditions. Of the sealing material can be prevented, and the appearance and aesthetics of the surface of the sealing material can be sealed well without impairing the properties of the sealing material.

EXAMPLES Hereinafter, the present invention will be described in more detail with reference to Examples and Comparative Examples. The parts are parts by weight, and the test methods for the performance of the sealing material shown in Examples are as follows. (1) Viscosity Using a HBF viscometer and setting the rotation speed to 10 times / minute,
The viscosity of the sample sealing material at each temperature (5, 20, 35 ° C.) was measured. (2) Tensile adhesion test A test body was prepared by a test method according to JIS A5758, and a tensile test was performed after standard curing. In addition, the adhesive performance
The 50% tensile stress, the maximum tensile stress, the elongation at break, and the rupture situation were used as scales. (3) Method of evaluating the surface of the sealing material The sealing material which was kneaded open at normal pressure for 10 minutes was poured into joints (width 30 mm, depth 15 mm, length 1 m) inevitably containing air bubbles, and a spatula was used. Finished.
After standing at a temperature of 20 ° C. and a humidity of 65% for 7 days, the appearance of the surface of the sealing material was visually inspected, and the number of crater-shaped avatars generated on the surface was examined. The crater-shaped avatar means one having a diameter of 2 mm or more.

Examples 1 and 2 As shown in Table 1, the polysulfide polymer LP-55 (manufactured by Toray Thiokol Co.) was added with a plasticizer,
A colorant, a filler and the like were added and kneaded to obtain 317.2 parts of a base mainly composed of a liquid polysulfide polymer.

[0014]

[Table 1]

As shown in Table 2, the curing agent was prepared by adding a diluent to lead dioxide to obtain 32.3 parts.

[0016]

[Table 2]

The above-mentioned bases and curing agents have particle sizes of 1 to 3 shown in Table 3.
6.5 parts of an A-type synthetic zeolite having an effective pore diameter of 4 μm and / or activated alumina having a particle diameter of 1 to 10 μm were added and mixed to obtain a polysulfide composition of the present invention.

[0018]

[Table 3]

The performance of this sealing material was tested as described above. As a result, the viscosity at each temperature (5, 20, 35 ° C.)
There was no difference as compared with the following comparative examples, the workability was maintained, and the adhesiveness was almost the same. Furthermore, the number of crater-shaped avatars was as small as 1, 3 when zeolite and activated alumina were used, respectively. Example 4 Except that activated alumina having a particle diameter of 10 to 100 μm shown in Table 3 was used and the addition amount was 3.3 parts, Examples 1 to 2 were used.
The sealing material of the present invention was obtained in the same manner as described above. Using this sealing material, the viscosity, the adhesion test, and the evaluation of the surface of the sealing material were performed in the same manner as in the above Examples. As a result, there was no difference in viscosity and adhesiveness as compared with the following comparative examples, and the number of crater-like avatars was as small as 5 as obtained. Example 6 The temperature and humidity of the method for evaluating the surface of the sealing material described above were changed to 5 ° C., 45%, 35 ° C., 7 other than 20 ° C. and 65%.
A sealing material of the present invention was obtained in the same manner as in Example 1 except that each evaluation was performed at 0%. Using this sealing material, the surface of the sealing material was evaluated. as a result,
As for the number of crater-shaped avatars, a small value of 1, 3 was obtained at each of 5, 35 ° C. Comparative Example As shown in Table 3, the same operation as in Example 1 was performed without adding any of the above zeolite and activated alumina to obtain a comparative sealing material. The number of crater-shaped avatars of this sealing material was 30, and the appearance of the sealing material was poor.

Claims (1)

(57) [Claims] 1. A base comprising liquid polysulfide as a main component and a curing agent comprising lead dioxide as a main component, wherein the base and / or the curing agent contain zeolite or activated alumina .
A polysulfide composition comprising 0.2 to 36.0% by weight of at least one material improving agent selected from the group consisting of liquid polysulfide.