JP3080835B2 - Room temperature curable composition - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a composition which cures to a rubbery state by reacting with atmospheric moisture at room temperature, and more particularly to a room temperature curable composition useful as a sealing material or an elastic adhesive.

[0002]

2. Description of the Related Art As a polymer which cures to a rubbery state by reacting with atmospheric moisture, for example, as described in JP-B-61-18852, at least one polymer having a hydrolyzable silyl group is used. At one end, the backbone is essentially a propylene oxide polymer and has a molecular weight of 6,300-1
5,000. A composition in which calcium carbonate, a plasticizer, an organic thixotropic agent, and the like are blended with this polymer is used as a sealing material or an elastic adhesive.

[0003]

However, the above-described current composition has various disadvantages in terms of workability during construction when used as a sealing material or an elastic adhesive. The workability during construction means that the sealing material or the adhesive does not sag during coating (sagging), it is easy to extrude from the filled cartridge (pushability), the thread breaks well, and the surrounding adherend Do not stain (yarn breakability)
However, there is a problem that these workability is inferior. An object of the present invention is to provide a room-temperature curable composition that eliminates the above-mentioned drawbacks and does not impair other physical properties and has good workability in coating.

[0004]

The polymer (A) used in the present invention has a main chain of essentially a propylene oxide polymer and has a crosslinkable hydrolyzable silyl group at a terminal. . The polymer (A) is described in, for example,
It can be synthesized by the method described in JP-A-72527. That is, in the presence of a double metal cyanide complex catalyst, a polyhydric alcohol is used as an initiator, propylene oxide is subjected to ring-opening addition polymerization, and then the hydroxyl group at the molecular end is converted into an unsaturated group, which is further hydrolyzed to an unsaturated group. It is obtained by reacting a hydrosilicon compound having a group.

[0005] The hydrolyzable silyl group-terminated propylene oxide polymer synthesized in this manner can be produced by a conventional method, for example, the method described in JP-B-61-18852.
A polymer having a high molecular weight and a narrow molecular weight distribution is obtained. In the present invention, the molecular weight of the polymer (A) is from 10,000 to 30,000.
A molecular weight distribution (Mw / Mn) of 1.6 or less is used. If the molecular weight is smaller than 10,000, the elongation after curing is small, and if it is larger than 30,000, the viscosity becomes high and workability becomes difficult. On the other hand, if the molecular weight distribution is larger than 1.6, the content of a low molecular weight substance or a high molecular weight substance in the system increases, which impairs tensile properties (elongation) and viscosity.

The hydrolyzable silyl group is represented by the following formula:

[0007]

Embedded image

Wherein X is a hydrolyzable group, R is a monovalent hydrocarbon group, and k is an integer of 0, 1 or 2, and the hydrolyzable group X is an alkoxy group, especially Methoxy groups are desirable from the balance of reactivity. Also, k is desirably 1 from the viewpoint of easy handling of reactivity.

The fatty acid amide wax (B) used in the present invention comprises N, N'-ethylenebis (stearoamide), oleic amide, stearic amide,
It is mainly composed of amides and bisamides of higher fatty acids such as N'-methylenebis (stearoamide). The addition amount is 0.1 to 100 parts by weight of the polymer (A).
It is 1 to 10 parts by weight. If the amount is less than 0.1 part by weight, it is easy to hang, and if it is more than 10 parts by weight, it is difficult to extrude.

The amount of methanol (C) used in the present invention is 0.1 to 10 parts by weight based on 100 parts by weight of polymer (A). If the amount is less than 0.1 part by weight, the yarn breaking property is deteriorated, and if it is more than 10 parts by weight, the sagging property is deteriorated.

[0011] A curing catalyst may be added to the room temperature curable composition of the present invention to accelerate the curing reaction. As a curing catalyst, a known silanol condensation catalyst is used. For example, tetrabutyl titanate, titanates such as tetrapropyl titanate, dibutyltin dilaurate, dibutyltin maleate, dibutyltin diacetate, tin octylate, tin carboxylate such as tin naphthenate, a reaction product of dibutyltin oxide and phthalate , Organic aluminum compounds such as dibutyltin diacetylacetonate, aluminum trisacetylacetonate, aluminum trisethylacetoacetate, diisopropoxyaluminum ethylacetoacetate, chelating compounds such as zirconium tetraacetylacetonate, titanium tetraacetylacetonate, octyl Use lead acid and other acidic and basic catalysts. These can be used alone or in combination of two or more.

[0012] In addition to the above-mentioned components, the composition of the present invention may further contain, if necessary, a physical property modifier for improving tensile properties, a filler, a reinforcing material, a plasticizer, a coloring agent, an antioxidant, An additive such as a flame retardant may be blended. Examples of the physical property modifier for improving the tensile properties include various silane coupling agents, for example, a silicon compound containing one silanol group in one molecule, and one silanol group in one molecule after being hydrolyzed. And the like.

Examples of fillers include calcium carbonate, magnesium carbonate, hydrous silicic acid, silicic anhydride, calcium silicate, silica, titanium dioxide, clay, talc, carbon black and the like. These fillers may be used alone or in combination of two or more.

Further, a plasticizer may be added in order to enhance elongation properties after curing and to reduce the modulus.
Examples of the plasticizer include phosphoric esters such as tributyl phosphate and tricresyl phosphate; phthalic esters such as dioctyl phthalate; monobasic esters of fatty acids such as glycerin monooleate; dibasic acids such as dibutyl adipate and dioctyl adipate; Use esters. These can be used alone or in combination of two or more. In addition to the above, a dehydrating agent, a pigment, an ultraviolet absorber, an antioxidant, and the like for removing moisture in the composition during storage may be added.

[0015]

The composition of the present invention is excellent in sagging property, thread breaking property, and extruding property at the time of construction and after the construction by the action of the hydrolyzable silyl group-terminated propylene oxide polymer, fatty acid amide wax and methanol. Reacts with atmospheric moisture at room temperature, undergoes a crosslinking reaction, and cures.

[0016]

EXAMPLES Next, the room temperature curable composition of the present invention will be described with reference to examples. (Example 1) Number average molecular weight 17000, molecular weight distribution 1.
No. 4 hydrolyzable silyl group-terminated propylene oxide polymer ("Exester 2410" manufactured by Asahi Glass Co., Ltd.) (A) 100
2 parts by weight of fatty acid amide wax (“DISPARON # 6500” manufactured by Kusumoto Kasei Co., Ltd.) (B), 100 parts by weight of calcium carbonate as a filler and 20 parts by weight of titanium dioxide
After adding 2 parts by weight and dispersing at 120 ° C. for 2 hours, 30 parts by weight of dioctyl phthalate as a plasticizer was uniformly dispersed with a sealed stirrer. Further, 2 parts by weight of dibutyltin dilaurate as a curing catalyst (D), and 2 parts by weight of vinyltrimethoxylane and 3 parts by weight of methanol (C) were added and uniformly dispersed to prepare a room-temperature curable composition.

Example 2 The same formulation as in Example 1 except that 4 parts by weight of fatty acid amide wax (“Dispalon # 6500” manufactured by Kusumoto Kasei) and 5 parts by weight of methanol (C) were used. Thus, a room temperature curable composition was prepared.

Comparative Example 1 A room temperature curable composition was prepared in the same manner as in Example 1 except that the fatty acid amide wax (B) and methanol (C) were not blended.

Comparative Example 2 A room temperature curable composition was prepared in the same manner as in Example 1 except that methanol (C) was not blended.

Comparative Example 3 The same formulation as in Example 1 except that 4 parts by weight of fatty acid amide wax (“Dispalon # 6500” manufactured by Kusumoto Kasei) and 15 parts by weight of methanol (C) were used. Thus, a room temperature curable composition was prepared.

Comparative Example 4 A fatty acid amide wax ("DISPARON # 6500" manufactured by Kusumoto Kasei Co., Ltd.) (B) was added to 15
A room temperature curable composition was prepared in the same manner as in Example 1 except that the amount by weight of methanol (C) was changed to 4 parts by weight.

(Evaluation) Evaluation was made on three items, sag, extrusion, and thread breakage. The sagging property is JIS-A
Based on 5758, 0mm is A, 3
Less than mm was evaluated as B and 3 mm or more as C. The extrudability was evaluated based on JIS-A5758 as A for less than 3 seconds, B for 3 seconds or more and less than 6 seconds, and C for 6 seconds or more from the level of extrudability.

The yarn breakability was measured by the following method. That is, the sample composition was filled between two stainless steel disks having a radius of 10 mm and a thickness of 5 mm. Filling part thickness is 3mm
And The upper disk is fixed and the lower disk weighs 50
g, and the lower disk was allowed to fall freely. At that time, the stringing length of the sample composition was measured. A: Stringing length less than 40 mm, B: 40 mm or more and less than 60 mm
0 mm or more was evaluated as C.

Table 1 shows the results of the above evaluation together with the formulation.
Shown in

[0025]

[Table 1]

As can be seen from the evaluation results, all of the compositions of Examples have good workability such as sagging property, extrusion property and thread breaking property, but the fatty acid amide wax (B) and methanol (C) In the composition without addition of, the sagging property and thread breaking property are poor, and in the composition without adding methanol (C), the sagging property, extrusion property and thread breaking property are not sufficient. Conversely, if methanol (C) is added in a specified amount or more, sagging and thread breakage will be poor, and if fatty acid amide wax (B) is added in excess, extrudability will be poor.

[0027]

As described above and as can be seen from the evaluation of the examples, the composition of the present invention has a sagging property in its construction,
This is a room-temperature curable composition that has excellent workability such as extrudability and thread breakability, and also has excellent curing performance at room temperature after construction, and is useful as a sealing material and an adhesive.

──────────────────────────────────────────────────続 き Continued on the front page (58) Field surveyed (Int. Cl. ⁷ , DB name) C08L 71/00-71/14 C08G 65/00-65/48 WPI / L

Claims (1)

(57) [Claims] 1. The main chain has a number average molecular weight of 10,000-3.
A propylene oxide polymer having a molecular weight distribution (Mw / Mn) of 1.6 or less and a polymer (A) having a crosslinkable hydrolyzable silyl group at the terminal (100 parts by weight) and a fatty acid amide wax ( (B) 0.1 to 10 parts by weight of methanol (C) 0.1 to 10 parts by weight).