JP2003342465A - Moisture curable composition - Google Patents

Abstract

(57) [Problem] The present invention has a low viscosity before curing, has good workability, is flexible after curing, can be filled with high conformability to outer wall joints, and has a plasticizer. Provided is a moisture-curable composition that does not migrate to contaminate the periphery of a sealing portion or reduce adhesiveness. SOLUTION: The main chain is essentially a (meth) acrylate copolymer, and a hydroxyl group or a hydrolyzable group is directly bonded to a silicon atom, and silicon-containing can be crosslinked by forming a siloxane bond. The organic polymer (A) having at least one organic group and the main chain are essentially polyalkylene oxide, and a hydroxyl group or a hydrolyzable group is directly bonded to a silicon atom, and is crosslinked by forming a siloxane bond. Having at least one silicon-containing organic group that can be
A moisture-curable composition comprising an organic polymer (B) having a number average molecular weight of 5000 or less.

Description

Detailed Description of the Invention

[0001]

TECHNICAL FIELD The present invention relates to a composition capable of exhibiting higher weather resistance and having excellent workability and elongation property, which is cured at room temperature in the presence of moisture.

[0002]

2. Description of the Related Art Organic polymers having one or more hydrolyzable silicon groups in the molecule are used for sealing materials, adhesives, coating materials, etc., by taking advantage of the fact that a cured product has a rubber-like shape. There is.

The higher the number average molecular weight of these polymers, the higher the flexibility of the cured product and the high followability when filling the outer wall joints, but the viscosity of the polymer before curing is high,
On the other hand, the workability is remarkably poor. On the other hand, when the number average molecular weight is low, the viscosity of the polymer before curing is low, but the cured product has low flexibility.

Heretofore, a method of adding various plasticizers has been adopted in order to reduce the viscosity before curing while maintaining the flexibility of the cured product. As these plasticizers, for example,
Phosphates such as tributyl phosphate and tricresyl phosphate, phthalates such as dioctyl phthalate, fatty acids such as glycerin monooleate 1
Basic acid esters and polypropylene glycols were used.

However, since these plasticizers have a migration property, they have a drawback that they bleed over the surface of the cured product over time, contaminate the periphery of the sealing part, and deteriorate the adhesiveness.

[0006]

SUMMARY OF THE INVENTION In view of the above-mentioned drawbacks, an object of the present invention is to fill the outer wall joint or the like with high followability, having a low viscosity and good workability before curing, and being flexible after curing. The present invention is to provide a moisture-curable composition in which the plasticizer migrates and the periphery of the sealing part is not contaminated and the adhesiveness is not deteriorated.

[0007]

In the moisture curable composition according to claim 1, the main chain is essentially a (meth) acrylic acid ester copolymer, and the hydroxyl group or hydrolyzable group is directly bonded to the silicon atom. 0.1 to 100 parts by weight of an organic polymer (A) having at least one silicon-containing organic group which is bonded and can be crosslinked by forming a siloxane bond, and the main chain is essentially a polyalkylene oxide, An organic polymer (B) in which a hydroxyl group or a hydrolyzable group is directly bonded to a silicon atom, has at least one silicon-containing organic group which can be crosslinked by forming a siloxane bond, and has a number average molecular weight of 5000 or less. It is characterized by containing 100 parts by weight.

The moisture-curable composition according to claim 2 is
The main chain is essentially a (meth) acrylic acid ester copolymer, a hydroxyl group or a hydrolyzable group is directly bonded to a silicon atom, and at least a silicon-containing organic group that can be crosslinked by forming a siloxane bond is used. Organic polymer (A) having one, a main chain is essentially a polyalkylene oxide, a hydroxyl group or a hydrolyzable group is directly bonded to a silicon atom, and a silicon-containing compound capable of being crosslinked by forming a siloxane bond An organic polymer (B) having at least one organic group and a number average molecular weight of 5000 or less and the main chain is essentially polyalkylene oxide, and the hydroxyl group or hydrolyzable group is directly bonded to the silicon atom. Contains an organic polymer (C) having at least one silicon-containing organic group capable of being crosslinked by forming a siloxane bond and having a number average molecular weight of 10,000 or more. And wherein the door.

In the organic polymer (A), the main chain is essentially a (meth) acrylic acid ester copolymer, and a hydroxyl group or a hydrolyzable group is directly bonded to a silicon atom to form a siloxane bond. It is an organic polymer having at least one silicon-containing organic group that can be crosslinked by the treatment, and a typical example thereof is an acrylic modified silicone polymer, which has at least one hydrolyzable silyl group at the end. Coalescence is preferred.

Among the organic polymers (A), the main component is a monomer selected from the group consisting of an acrylic acid alkyl ester having a main chain of 1 to 12 carbon atoms and an alkyl group of a methacrylic acid alkyl ester having 1 to 14 carbon atoms. Are preferred.

Examples of the alkyl (meth) acrylate include methyl (meth) acrylate, ethyl (meth) acrylate, propyl (meth) acrylate, butyl (meth) acrylate, hexyl (meth) acrylate, octyl (meth) acrylate, 2-ethylhexyl (meth) acrylate etc. are mentioned.

The silicon-containing organic group in which the above-mentioned hydroxyl group or hydrolyzable group is directly bonded to a silicon atom and which can be crosslinked by forming a siloxane bond is not particularly limited, but a methoxysilyl group, Alkoxysilyl groups such as an ethoxysilyl group, a methyldimethoxysilyl group, a methyldiethoxysilyl group, and a methyldimethylmethoxysilyl group do not produce harmful by-products after the reaction and are preferably used.

Examples of the above organic polymer (A) include "MS Polymer S-903", "MS Polymer MAX-911", "MS Polymer MA-430" manufactured by Kanebuchi Chemical Co., Ltd.
It is commercially available as “MS polymer MA-447” and the like.

In the organic polymer (B), the main chain is essentially polyalkylene oxide, the hydroxyl group or the hydrolyzable group is directly bonded to the silicon atom, and the silicon which can be crosslinked by forming a siloxane bond. An organic polymer having at least one containing organic group and having a number average molecular weight of 5000 or less. A typical example thereof is a modified silicone polymer, which has one hydrolyzable silyl group only at one end. Organic polymers are preferred.

As the above polyalkylene oxide,
It is not particularly limited, and examples thereof include polyethylene oxide, polypropylene oxide, polybutylene oxide, and the like, and polypropylene oxide excellent in water resistance and elasticity is preferable.

The at least one silicon-containing organic group contained in the organic polymer (B) has a hydroxyl group or a hydrolyzable group directly bonded to a silicon atom and can be crosslinked by forming a siloxane bond. , The organic polymer (A)
Is an organic group of the same type as the silicon-containing organic group of.

When the number average molecular weight of the organic polymer (B) is large, the viscosity of the moisture-curable composition is high,
Since workability is reduced, those of 5000 or less are used.

A typical example of the organic polymer (B) is a modified silicone polymer, which is commercially available from Asahi Glass Co., Ltd. under the trade name "Excester ESSX-2000".

In the organic polymer (C), the main chain is essentially polyalkylene oxide, the hydroxyl group or the hydrolyzable group is directly bonded to the silicon atom, and silicon which can be crosslinked by forming a siloxane bond. An organic polymer having at least one containing organic group and having a number average molecular weight of 10,000 or more. A typical example thereof is a modified silicone polymer, and an organic polymer having at least one hydrolyzable silyl group. Is preferred.

As the above polyalkylene oxide,
It is not particularly limited, and examples thereof include polyethylene oxide, polypropylene oxide, polybutylene oxide, and the like, and polypropylene oxide excellent in water resistance and elasticity is preferable.

The silicon-containing organic group having at least one organic polymer (C) has a hydroxyl group or a hydrolyzable group directly bonded to a silicon atom and can be crosslinked by forming a siloxane bond. , The organic polymer (A)
Is an organic group of the same type as the silicon-containing organic group of.

When the number average molecular weight of the organic polymer (C) is small, the elongation of the moisture-curable composition is reduced when the composition is cured, and the conformability to joints is deteriorated.
000 or more are used.

A typical example of the above-mentioned organic polymer (C) is a modified silicone polymer, which is a product name "MS Polymer S-203" and "MS Polymer S-30" manufactured by Kaneka Corporation.
3 "," MS Polymer S-903 "," MS Polymer M "
AX-908 "," MS Polymer MAX-911 ",
"Cyril SAT-200", "Cyril MA-43"
0 ”,“ Cyril EST-250 ”,“ Cyril SAT
-350 "," Cyril SAT-400 ", etc.
Also, Asahi Glass Co., Ltd., under the trade name “Excester ESS-362
0 "" Exestar ESS-3430 "" Exestar ESS-2420 "" Exestar ESS-2410 "
Etc. are commercially available.

The organic polymer (B) and the organic polymer (C) are obtained by, for example, hydrogenating a polyalkylene oxide having an allyl group at the terminal in the presence of a Group VIII transition metal and represented by the following general formula. Obtained by reacting with a silicon compound. X _3-a -Si (R _a ) -H (In the formula, R is 1
Valent hydrocarbon group or halogenated monovalent hydrocarbon group, a is 0
To an integer of 2 and X represents an atom or a group selected from the group consisting of a halogen atom, an alkoxy group, an acyloxy group and a ketoximate group. )

The amount of the organic polymer (A) used is preferably 0.1 to 100 parts by weight, more preferably 100 parts by weight based on 100 parts by weight of the total amount of the organic polymer (B) and the organic polymer (C). 0.5 to 80 parts by weight. If it is less than 0.1 part by weight, the effect of improving the weather resistance becomes small, and if it exceeds 100 parts by weight,
Curability and elongation are reduced.

The amount of the organic polymer (B) used is preferably 1 to 200 parts by weight with respect to 100 parts by weight of the organic polymer (C). If it is less than 1 part by weight, the effect of improving workability becomes small, and if it exceeds 200 parts by weight, curability and elongation are lowered.

The moisture-curable composition of the present invention comprises the organic polymer (A) and the organic polymer (B), or the organic polymer (A), the organic polymer (B) and the organic polymer ( C), but a silanol condensation catalyst is preferably added to the moisture curable composition in order to accelerate the moisture curing reaction.

As the silanol condensation catalyst, a conventionally known silanol condensation catalyst used to accelerate the moisture curing reaction of the modified silicone polymer can be used.

For example, dibutyltin dilaurate, dibutyltin oxide, dibutyltin diacetate, dibutyltin acetate, bis (dibutyltin lauric acid) oxide, dibutyltin bisacetylacetonate, dibutyltin bis (monoester malate), octyl acid. Tin compounds such as tin, dibutyltin octoate and dioctyltin oxide, titanate compounds such as tetra-n-butoxy titanate and tetraisopropoxy titanate, amine salts such as dibutylamine-2-ethylhexoate and other acidic catalysts and Examples thereof include basic catalysts, which can be used alone or in combination of two or more kinds.

The content of the silanol condensation catalyst is not particularly limited, but 0.1 to 60 parts by weight of the total amount of the organic polymers (A), (B) and (C) is used as the silanol condensation catalyst. It is preferably 5 parts by weight, more preferably 0.5 to 3 parts by weight.

If the amount is less than 0.1 part by weight, a sufficient curing acceleration effect may not be obtained, and if the amount exceeds 5 parts by weight,
Even though the curing acceleration effect is no longer improved, the cost becomes high.

In order to improve the adhesive performance, a compound having an amino group and an alkoxysilyl group in one molecule may be added as an adhesiveness-imparting agent. For example, 3-aminopropyltrimethoxysilane, 3-aminopropylmethyldimethoxysilane, 3-aminopropyltriethoxysilane, N- (2-aminoethyl) -3-aminopropyltrimethoxysilane, N- (2-aminoethyl ) -3-Aminopropylmethyldimethoxysilane, N- (2-aminoethyl) -3-aminopropyltriethoxysilane, N, N'-
Bis- [3- (trimethoxysilyl) propyl] ethylenediamine, N, N'-bis- [3- (triethoxysilyl) propyl] ethylenediamine, N, N'-bis- [3--
(Methyldimethoxysilyl) propyl] ethylenediamine, N, N'-bis- [3- (trimethoxysilyl) propyl] hexamethylenediamine, N, N'-bis- [3
-(Triethoxysilyl) propyl] hexamethylenediamine, N, N'-bis- [3- (methyldimethoxysilyl) propyl] hexamethylenediamine, N, N-bis-
[3- (trimethoxysilyl) propyl] ethylenediamine, N, N-bis- [3- (triethoxysilyl) propyl] ethylenediamine, N, N-bis- [3- (methyldimethoxysilyl) propyl] ethylenediamine, N, N-bis
-[3- (trimethoxysilyl) propyl] hexamethylenediamine, N, N-bis- [3- (triethoxysilyl) propyl] hexamethylenediamine, N, N-bis-
[3- (methyldimethoxysilyl) propyl] hexamethylenediamine, N, N-bis- [3- (trimethoxysilyl) propyl] amine, N, N-bis- [3- (triethoxysilyl) propyl] amine, N, N-bis- [3- (methyldimethoxysilyl) propyl] amine and the like,
These may be used alone or in combination of two or more.

The content of the adhesion-imparting agent is not particularly limited, but is 0.1 to 100 parts by weight of the total amount of the organic polymers (A), (B) and (C). It is preferably 20 parts by weight, more preferably 0.5 to 1
5 parts by weight.

If the amount is less than 0.1 parts by weight, the resulting moisture-curable composition will not exhibit sufficient adhesive force to the substrate,
If it exceeds 20 parts by weight, the physical properties of the sealing agent and the like may be adversely affected although the effect corresponding to the amount added cannot be expected.

Further, a dehydrating agent may be added to remove moisture in the moisture-curable composition. As the dehydrating agent,
For example, silane compounds such as vinyltrimethoxysilane, vinyldimethoxysilane, tetraethoxysilane, methyltrimethoxysilane, methyltriethoxysilane, tramethoxysilane, etc., methyl orthoformate, ethyl orthoformate, methyl orthoacetate, ethyl orthoacetate, etc. Examples of the hydrolyzable ester compounds are, and these may be used alone or in combination of two or more kinds.

The content of the dehydrating agent is not particularly limited, but 1 to 10 parts by weight of the adhesion promoter is added to 100 parts by weight of the total amount of the organic polymers (A), (B) and (C). Is preferable, and more preferably 1 to 8 parts by weight.

When the amount is less than 1 part by weight, a sufficient dehydrating effect cannot be obtained, and the moisture-curable composition thickens or gels during storage due to a trace amount of water in the moisture-curable composition. 10
When it exceeds the weight part, there are adverse effects such as delaying the curing time of the moisture curable composition.

Further, various fillers may be added if necessary. As the filler, calcium carbonate, magnesium carbonate, calcium oxide, hydrous silicic acid, silicic acid anhydride, fine powder silica, calcium silicate, titanium dioxide,
Examples thereof include clay, talc, carbon black and glass balloons, which may be used alone or in combination of two or more kinds. 200 per 100 parts by weight of the organic polymer
The amount is preferably not more than 170 parts by weight, more preferably not more than 170 parts by weight.

Further, if necessary, an antioxidant, an ultraviolet absorber, an antioxidant, a light stabilizer, a pigment, a solvent, a flame retardant, a fragrance, etc. may be added.

The method for producing the moisture-curable composition of the present invention comprises:
Any conventionally known method may be adopted. For example, the organic polymer (A) and the organic polymer (B) or the organic polymer (A), the organic polymer (B) and the organic polymer (C) are required. A silanol condensation catalyst, an adhesion promoter, a dehydrating agent, a filler, an antioxidant, an antioxidant, an ultraviolet absorber, a pigment, a fragrance, a solvent and the like are blended in a predetermined amount, and then kneaded by a roll or a planetary mixer. Obtained by

[0041]

BEST MODE FOR CARRYING OUT THE INVENTION Next, examples of the present invention will be described, but the invention is not limited to the following examples.

Example 1 70 parts by weight of an organic polymer having a number average molecular weight of 20,000 and having a methyldimethoxysilylpropyl group at the terminal as a main chain was a (meth) acrylic acid ester copolymer, and the main chain was propylene oxide. 30 parts by weight of an organic polymer having a number average molecular weight of 5000 having a methyldimethylmethoxysilylpropyl group only at one end, 2 parts by weight of dibutyltin dilaurate as a curing catalyst, and calcium carbonate as a filler 10
0 part by weight was added and mixed to obtain a moisture-curable composition of the present invention.

Example 2 10 parts by weight of an organic polymer having a number average molecular weight of 20,000 and having a methyldimethoxysilylpropyl group at the terminal as the main chain was a (meth) acrylic acid ester copolymer, and the main chain was propylene oxide. 30 parts by weight of an organic polymer having a methyldimethylmethoxysilylpropyl group at only one end and a number average molecular weight of 5,000, and an organic polymer having a main chain of propylene oxide and having a methyldimethylmethoxysilylpropyl group at the end and having a number average molecular weight of 20,000 60 parts by weight and 2 parts by weight of dibutyltin dilaurate as a curing catalyst,
100 parts by weight of calcium carbonate was added and mixed as a filler to obtain the moisture-curable composition of the present invention.

Comparative Example 1 Propylene oxide in the main chain and a methyldimethylmethoxysilylpropyl group at the terminal, number average molecular weight 2000
30 parts by weight of a number average molecular weight of 5000 having a main chain of propylene oxide and having a methyldimethylmethoxysilylpropyl group only at one end, and 70 parts by weight of an organic polymer of 0, and dibutyltin dilaurate 2 as a curing catalyst. By weight, 100 parts by weight of calcium carbonate as a filler was added and mixed to obtain a moisture-curable composition.

Comparative Example 2 Propylene oxide in the main chain and a methyldimethylmethoxysilylpropyl group at the end, number average molecular weight 2000
2 parts by weight of dibutyltin dilaurate as a curing catalyst and 100 parts by weight of calcium carbonate as a filler were added to 100 parts by weight of the organic polymer of No. 0 and mixed to obtain a moisture curable composition.

Comparative Example 3 Propylene oxide in the main chain and a methyldimethylmethoxysilylpropyl group at the terminal, number average molecular weight 2000
30 parts by weight of an organic polymer having a number average molecular weight of 5,000, which has a main chain of propylene oxide and a methyldimethylmethoxysilylpropyl group at the end, and 70 parts by weight of an organic polymer of 0, and 2 parts by weight of dibutyltin dilaurate as a curing catalyst Then, 100 parts by weight of calcium carbonate as a filler was added and mixed to obtain a moisture-curable composition.

The workability before curing, the elongation after curing and the weather resistance of the obtained moisture-curable composition were measured, and the results are shown in Table 1. The methods for measuring each physical property are as follows.

(1) Workability The obtained moisture-curable composition was applied to joints by five people, and a sensory test was carried out to evaluate it on a 5-point scale. The evaluation criteria are 5; very good, 4; good, 3; normal, 2; somewhat inferior, 1; inferior,
And

(2) Elongation at maximum load JIS A 5758 (sealing material for construction) 4.14
The tensile adhesiveness test (measurement under non-primer conditions using an aluminum plate as an adherend) according to the above was performed to measure the elongation at maximum load.

(3) Weather resistance test After curing, irradiation was performed with a sunshine weatherometer. Irradiation conditions conform to JIS A 1415 WS type, discharge voltage 50 ± 2V, discharge current 60 ± 2A, spray water pressure 7
8.4 to 117.6 kPa, water amount 2100 ± 100 ml
/ Min, 18 minutes in a spray cycle of 120 minutes, a black panel temperature of 63 ± 3 ° C., and an irradiation time of 4000 hours, and the elongation after the test was measured.

[0051]

[Table 1]

[0052]

The composition of the moisture-curable composition of the present invention is as described above, so that it has a low viscosity and good workability before curing, is flexible after curing, and fills outer wall joints with high followability. In addition, the plasticizer does not migrate to contaminate the periphery of the sealing portion or reduce the adhesiveness.

Claims (2)

[Claims] 1. A silicon having a main chain which is essentially a (meth) acrylic acid ester copolymer, a hydroxyl group or a hydrolyzable group directly bonded to a silicon atom, and which can be crosslinked by forming a siloxane bond. 0.1 to 100 parts by weight of an organic polymer (A) having at least one containing organic group and the main chain are essentially polyalkylene oxides, and a hydroxyl group or a hydrolyzable group is directly bonded to a silicon atom, A moisture-curable composition comprising 100 parts by weight of an organic polymer (B) having at least one silicon-containing organic group capable of crosslinking by forming a siloxane bond and having a number average molecular weight of 5000 or less. . 2. A silicon which has a main chain essentially of a (meth) acrylic acid ester copolymer, a hydroxyl group or a hydrolyzable group is directly bonded to a silicon atom, and which can be crosslinked by forming a siloxane bond. An organic polymer (A) having at least one containing organic group, the main chain of which is essentially polyalkylene oxide, and the hydroxyl group or hydrolyzable group is directly bonded to a silicon atom to form a siloxane bond. An organic polymer (B) having at least one crosslinkable silicon-containing organic group and having a number average molecular weight of 5000 or less, and the main chain being essentially a polyalkylene oxide, and the hydroxyl group or hydrolyzable group being a direct silicon atom. An organic polymer (C having a number average molecular weight of 10,000 or more) having at least one silicon-containing organic group that is crosslinked by forming a siloxane bond. ) Is contained, the moisture-curable composition characterized by the above-mentioned.