JPH07138337A - Moisture-curable composition excellent in storage stability - Google Patents

Abstract

PURPOSE:To obtain a moisture-curable compsn. which has an excellent storage stability without requiring strict control of moisture content by compounding a polyisocyanate compd. specific compds. and CaCO3. CONSTITUTION:This compsn. contains a polisocyanate compd., a compd. having at least two silylthio groups (e.g. a compd. formed by modifying molecular ends of a polysulfide polymer with silylthio groups), CaCO3 coated with a fatty acid ester (e.g. stearyl stearate), and a compd. of formula I (wherein R<1> is H, F, or a 1-20C mono- or divalent org. group provided it is bonded to an Si atom through Si-B bond or Si-C bond; R<2> is a 1-30C mono- or divalent org. group; and (n) is 0-3) or formula II (wherein R<3> to R<5> and R<7> are each R<4>; R<6> is R<2>; (l) and (m) are each the number of repeating units; and (n) is 0 or higher) having at least one silyl ester group.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a moisture-curable composition having excellent storage stability, and more particularly, to controlling the moisture content of fillers, plasticizers and the like added to the composition to an extremely low rate. The present invention relates to a moisture-curable composition having excellent storage stability, which can ensure good storage stability without strict water management.

[0002]

2. Description of the Related Art As a curable composition used for building sealants and the like, a polymer containing two or more isocyanate groups in one molecule and a compound containing a trialkylsilylthio group or a triphenylsilylthio group. The one-component moisture-curable composition containing the compound does not expand or foam during curing and has excellent curability as compared with the conventional one-component curable polyurethane composition. 14
It is proposed in Japanese Patent No. 5321. However, since the silylthio group reacts extremely easily with water, in order to maintain the storage stability of such a moisture-curable composition, the water content of these additives should be kept extremely low when blending fillers, plasticizers, etc. Strict water management is required. However, it is very difficult in practice to control the water content of these additives and the like, which is a serious problem in producing the moisture-curable composition.

[0003]

SUMMARY OF THE INVENTION The present invention has been made in view of the above circumstances, and strictly controls the moisture content of fillers, plasticizers and the like added to the composition to an extremely low rate. It is an object of the present invention to provide a moisture-curable composition having excellent storage stability, which can ensure good storage stability without needing to perform proper water management.

[0004]

In order to achieve such an object, the moisture-curable composition of the present invention has a surface of a polyisocyanate compound, a compound having two or more silylthio groups in the molecule, and a fatty acid ester. Treated calcium carbonate, and general formula,

[Chemical 5] (R ¹ is a hydrogen atom or a monovalent or divalent organic group or a fluorine having 1 to 20 carbon atoms, silicon - hydrogen bonds or silicon - .R ¹ coupled to silicon atom through a carbon bond, Examples are methyl, ethyl, dodecyl, aminoethyl, vinyl, methylvinyl, isobutyl, phenyl, benzyl, fluoro groups, etc. R ² is
It is a monovalent or divalent organic group having 1 to 30 carbon atoms, and examples thereof include methyl, butyl, lauryl, stearyl, oxalyl and malonyl. Y is an oxygen atom or a nitrogen atom, and n is an integer selected from 0, 1, 2, and 3. ) Or

[Chemical 6] (In the formula, R ³ , R ⁴ , R ⁵ , and R ⁷ each independently represent an atom or atomic group in the same range as R ^1, and R ⁶ represents an atom or atomic group in the same range as R ² . l and m are the number of repeating units, and n is O or a positive integer.) A compound having at least one silyl ester group in the molecule is contained. Here, it is preferable that 40 to 120 parts by weight of calcium carbonate surface-treated with a fatty acid ester is contained with respect to 100 parts by weight of the prepolymer.

Further, with respect to 100 parts by weight of calcium carbonate surface-treated with a fatty acid ester, the general formula:

[Chemical 7] (R ¹ is a hydrogen atom or a monovalent or divalent organic group or a fluorine having 1 to 20 carbon atoms, silicon - hydrogen bonds or silicon - .R ¹ coupled to silicon atom through a carbon bond, Examples are methyl, ethyl, dodecyl, aminoethyl, vinyl, methylvinyl, isobutyl, phenyl, benzyl, fluoro groups, etc. R ² is
It is a monovalent or divalent organic group having 1 to 30 carbon atoms, and examples thereof include methyl, butyl, lauryl, stearyl, oxalyl and malonyl. Y is an oxygen atom or a nitrogen atom, and n is an integer selected from 0, 1, 2, and 3. ) Or

[Chemical 8] (In the formula, R ³ , R ⁴ , R ⁵ , and R ⁷ each independently represent an atom or atomic group in the same range as R ^1, and R ⁶ represents an atom or atomic group in the same range as R ² . 1 and m are the number of repeating units, and n is O or a positive integer.) 0.1 to 10 parts by weight of a compound having at least one silyl ester group in the molecule is contained. Preferably.

The present invention will be described in detail below. The essential components of the present invention are the following four components.

(1) Polyisocyanate compound A polyisocyanate compound having the general formula RN
Is a compound having a structure represented by ═C═O. In the present invention, those having a molecular weight of 500 to 10,000 are preferable, and those having a molecular weight of 2,000 to 5,000 are more preferable from the viewpoint of curability and stable storage stability.

In the present invention, any polyisocyanate compound may be used, and specifically, m-phenylene diisocyanate, toluene-2,4-diisocyanate, hexamethylene-1,6-diamine. Isocyanate, tetramethylene-1,4-diisocyanate, cyclohexane-1,4-diisocyanate, naphthalene-1,5
-Diisocyanate, 1-methoxyphenyl-2,4-
Diisocyanates such as diisocyanate, diphenylmethane-4,4'-diisocyanate and 4,4'-biphenylene diisocyanate; 4,4 ', 4 "-triphenylmethane diisocyanate and toluene-
Triisocyanates such as 2,4,6-triisocyanate; 4,4'-dimethyldiphenylmethane-2,
Examples thereof include tetraisocyanate such as 2 ', 5,5'-tetraisocyanate. These polyisocyanate compounds may be used alone or in combination of two or more.

(2) Compound having two or more silylthio groups in the molecule Any compound which imparts curability to the composition of the present invention and which has two or more silylthio groups in the molecule is used in the present invention. The molecular weight is preferably 200 to 10,000, more preferably 300 to 3,000.
belongs to.

Specific examples of such a compound include:
Some examples are as follows. RR'R "SiS (CH ₂ CH ₂ OCH ₂ OCH ₂ CH ₂ S ₂ ) _q -CH ₂ CH ₂ OCH ₂ OCH ₂ CH ₂ S
SiRR'R "(wherein R 1, R ', and R" are alkyl groups having 1 to 6 carbon atoms, particularly a group selected from a methyl group, an ethyl group, a phenyl group, and a chloromethyl group; q is 0 to 25. of an integer) among other this _{compound, (CH 3) 3 SiS (} CH 2 CH 2 OCH 2 OCH 2 CH 2 S 2) r -CH 2 CH 2 OCH 2 OCH 2 CH 2
A compound of SSi (CH ₃ ) (where r is an integer of 1 to 10) is preferable.

In addition to this, RR'R "SiS (CH ₂ CH ₂ O) s-CH ₂ CH ₂ SSiRR'R", (wherein R, R ', R "are as described above; s is 0 50 of an _{integer) RR'R "SiSCH 2 COOCH 2 C} (CH 2 OCOCH 2 SSiRR'R") 3 - (RR'R "SiSCH
₂ CH ₂ COOCH ₂ . C ₂ H ₅ (in the formula, R, R ′ and R ″ are as described above) and the like are exemplified.

These compounds can be synthesized by reacting a known compound containing two or more thiol groups in the molecule with a commercially available silyl reagent to convert the thiol group into a trialkylsilylthio group. . This compound may be used alone or in combination of two or more.

The ratio of the silylthio group which is hydrolyzed to regenerate a thiol group by the isocyanate group and water in the polyisocyanate compound is such that the molar ratio of [silylthio group] / [isocyanate group] is 0.8 to 1 It is preferably adjusted in the range of 0.2.

(3) Calcium Carbonate Surface Treated with Fatty Acid Ester To impart thixotropy (thixotropy and slump resistance) to the composition of the present invention, it is added as a filler. The fatty acid ester as a surface treatment agent for calcium carbonate is preferably an ester of a higher fatty acid having 8 or more carbon atoms, for example,
Examples include stearyl stearate, lauryl stearate, stearyl palmitate, and lauryl palmitate.

In the present invention, the surface treatment of calcium carbonate with a fatty acid ester is for giving sufficient thixotropy. The method of surface treatment can be performed using a known method, and is not particularly limited. For example, a fatty acid ester is added to an aqueous slurry of calcium carbonate and kneaded to adsorb the fatty acid ester on the surface of calcium carbonate. A method can be mentioned.

In the composition of the present invention, the content of the calcium carbonate is not particularly limited, but the prepolymer 10
The content is preferably 40 to 120 parts by weight with respect to 0 parts by weight. This is because if it is less than 40 parts by weight, good thixotropy cannot be obtained, while if it exceeds 120 parts by weight, the viscosity becomes too high and the elongation of the cured product becomes poor. In addition,
In the present invention, the water content of calcium carbonate surface-treated with a fatty acid ester added as a filler may be about 0.1%, and strict water management is not required. By including the following compound (4) as an essential component in the present composition, as will be described later, storage stability as good as when the water content of calcium carbonate is about 1/10 is obtained. It is possible to obtain the composition of the present invention.

(4) Compound of the following formula 1 or formula 2

[Chemical 9] (R ¹ is a hydrogen atom or a monovalent or divalent organic group or a fluorine having 1 to 20 carbon atoms, silicon - hydrogen bonds or silicon - .R ¹ coupled to silicon atom through a carbon bond, Examples are methyl, ethyl, dodecyl, aminoethyl, vinyl, methylvinyl, isobutyl, phenyl, benzyl, fluoro groups, etc. R ² is
It is a monovalent or divalent organic group having 1 to 30 carbon atoms, and examples thereof include methyl, butyl, lauryl, stearyl, oxalyl and malonyl. Y is an oxygen atom or a nitrogen atom, and n is an integer selected from 0, 1, 2, and 3. )

[Chemical 10] (In the formula, R ³ , R ⁴ , R ⁵ , and R ⁷ each independently represent an atom or an atomic group in the same range as R ^1, and R ⁶ represents an atomic group in the same range as R ² . m is the number of repeating units, and n is O or a positive integer.) This compound has high hydrolysis reactivity and preferentially undergoes hydrolysis reaction with water in the composition system. . That is, the water contained in the calcium carbonate surface-treated with the fatty acid ester by the addition of the present compound is reacted with the present compound before the reaction with the silylthio group in the compound (2). First, the hydrolysis reaction is performed. Therefore, even if the water content of the calcium carbonate is about 0.1%, most of it is used for the hydrolysis reaction rather than the reaction with the silylthio group, and as a result, the water content of the calcium carbonate is It is possible to obtain the composition of the present invention having storage stability as good as that of about 1/10 of 0.01%.

The compound of the formula 1 corresponds to a corresponding halogenated silane compound SiR ¹ _n X _4-n (wherein X represents a halogen atom such as chlorine or bromine atom) and a corresponding carboxylic acid, carboxylic acid metal salt or Synthesized from carboxamide. The silicone oil represented by Formula 2 is a known substance, some of which are commercially available. For example, trade names KF-910 and X-22-8 manufactured by Shin-Etsu Chemical Co., Ltd.
00 or X-22-715.

In the composition of the present invention, the content of the compound of formula (1) or formula (2) above (4) is not particularly limited,
It is preferably contained in a proportion of 0.5 to 10 parts by weight with respect to 100 parts by weight of calcium carbonate surface-treated with a fatty acid ester. This is because if it is less than 0.1 parts by weight, there is no effect on the storage stability, and if it exceeds 10 parts by weight, the curing time is delayed.

The composition of the present invention is prepared by mixing the above-mentioned essential components in a predetermined amount and stirring and mixing. In particular, a silylthio group in the molecule of a polyisocyanate compound is 2
Alternatively, a mixture containing a compound having one or more compounds may be prepared in advance, and the calcium carbonate and the silyl ester group-containing compound may be added to the mixture in predetermined amounts, and the mixture may be stirred and mixed.

In addition to the above-mentioned essential components, a filler, a plasticizer, a solvent, an adhesion-imparting agent, a stabilizer, a colorant and the like may be contained within a range not impairing the gist of the present invention. Fillers include, for example, normal calcium carbonate, talc, kaolin,
Zeolites, diatomaceous earth, vinyl chloride paste resins, glass balloons, vinylidene chloride resin balloons, etc. are available. Solvents include, for example, aromatic hydrocarbons such as toluene and xylene, hexane, heptane, aliphatic hydrocarbons such as octane, acetone, ketones such as methyl ethyl ketone, and ether esters such as cellosolve acetate.
It is used in the range of 1 to 40% by weight based on the prepolymer. Adhesion-imparting agents include silane coupling agents, stabilizers include hindered phenol compounds, and coloring agents include titanium white, carbon black, red iron oxide, and the like.

[0022]

In the moisture-curable composition of the present invention, a polyisocyanate compound, a compound having two or more silylthio groups in the molecule, calcium carbonate surface-treated with a fatty acid ester, and a general formula:

[Chemical 11] (R ¹ is a hydrogen atom, a fluorine atom or a carbon number of 1 to 20.
Is a monovalent or divalent organic group, and is bonded to a silicon atom through a silicon-hydrogen bond or a silicon-carbon bond.
R ² is a monovalent or divalent organic group having 1 to 30 carbon atoms, and in the organic group, a functional group such as a halogen group, an alkoxy group, a nitrile group, an acid amide group, an ester group or an epoxy group. Can be included. Y is an oxygen atom or a nitrogen atom, and n is an integer selected from 0, 1, 2, and 3. ) Or

[Chemical 12] (In the formula, R ³ , R ⁴ , R ⁵ , and R ⁷ each independently represent an atom or an atomic group in the same range as R ^1, and R ⁶ represents an atomic group in the same range as R ² . m is the number of repeating units, and n is O or a positive integer.) Since it contains a compound having at least one silyl ester group in the molecule, it is included in the calcium carbonate. Since the water first undergoes a hydrolysis reaction with the silyl ester group-containing compound before the reaction with the silylthio group, the water content of the calcium carbonate is 0.1
%, Most of it is used for the hydrolysis reaction rather than the reaction with the silylthio group, and as a result, the water content of calcium carbonate is about 1/10 of 0.01%. It is possible to obtain the composition of the present invention with equally good storage stability.

[0023]

EXAMPLES The present invention will be described in detail below with reference to examples, but the present invention is not limited to these examples. (Example 1-4) Polyisocyanate compound and silie
A compound having two or more ruthio groups in the molecule (LP600), a urethane prepolymer having a terminal NCO,
LP600 (Toray Thiokol Co., Ltd.) consisting of a component obtained by modifying the end of a polysulfide polymer into a silylthio group.
Made). In this compound, a thiol group is regenerated from a silylthio group by hydrolysis with water, and this thiol group reacts with an isocyanate group to form a thiourethane bond, thereby cross-linking.

Calcium carbonate surface-treated with fatty acid ester
Umm (Sealets 300) "Sealets 300" (manufactured by Maruo Calcium Co., Ltd.) having a water content of 0.01% (Examples 1 and 2) and a water content of 0.1% (Example 3, 4) was selected. Sealets 300 has an average primary particle size of about 0.07 μm surface-treated with fatty acid ester and about 10% by weight of fatty acid ester.
It is calcium carbonate contained.

Compound containing silyl ester group (KF910
Or SIO-218) fatty acid ester-modified silicone oil "KF910";
Shin-Etsu Chemical Co., Ltd. (Examples 1, 2 and 4) and a fatty acid ester-modified organopolysiloxane compound (“SI
O-218 "; manufactured by Yokohama Rubber Co., Ltd. (Example 3) was used.

Table 1 shows the compounding ratio of each of these components. A mixture (“LP600”) of the polyisocyanate compound in the number of parts by weight shown in Table 1 and a compound having two or more silylthio groups in the molecule was placed in a container with a stirrer, and calcium carbonate surface-treated with fatty acid ester was added thereto The silyl ester group-containing compound was added, and the mixture was stirred at 55 ° C. for 60 minutes and mixed to obtain a moisture-curable composition of the present invention.

Comparative Example 1 A moisture-curable composition was obtained in the same manner as in Example 1, except that the silyl ester group-containing compound was not added.

Comparative Example 2 A moisture-curable composition was obtained in the same manner as in Example 3, except that the silyl ester group-containing compound was not added. Using the moisture-curable compositions of Examples and Comparative Examples thus obtained, the following tests were conducted and evaluated at the initial stage and after 24 hours.

[0029] was determined using viscosity B type viscometer (measured at rotor No.7,20 ℃). “Initial” refers to the viscosity (poise) when the composition is cooled to room temperature after being manufactured, and is “70 ° C. × 24
“Time” means 2 hours after the composition is kept at 70 ° C. for 24 hours.
Viscosity (poise) when cooled to 0 ° C.

T. F. T tack free time (curing time). A polyethylene sheet was lightly applied to the surface of the composition at intervals of 30 minutes, and the time was taken until the composition did not adhere to the polyethylene. "Initial" means a T.V. when a polyethylene sheet is applied at 30-minute intervals after the composition is cooled to room temperature after production. F. It is a T evaluation, and "70 ° C x 24 hours" means that the composition is 70 ° C.
After being kept at 20 ° C. for 24 hours, it was cooled to 20 ° C. and then a polyethylene sheet was applied at intervals of 30 minutes. F. It is a T evaluation.

[0031] * 1) Prepolymer containing polyisocyanate compound and compound having two or more silylthio groups in the molecule (Toray Thiokol Co., Ltd.) * 2) Fatty acid ester surface-treated calcium carbonate * 3) Fatty acid ester modified silicone oil * 4) Fatty acid ester modified silicone compound (manufactured by Yokohama Rubber Co., Ltd.)

As is clear from Table 1, the moisture-curable composition of the present invention has a moisture content of 0.01% even when a silyl ester group-containing compound having a moisture content of 0.1% is used. It is clear that it has the same degree of curability as when used. Further, this curability does not change either immediately after the production of the composition or after 24 hours of production, and it is clear from the table that the composition of the present invention has excellent storage stability.

[0033]

As described in detail above, according to the present invention,
Excellent storage stability, which can ensure good storage stability without strict water management that keeps the water content of fillers and plasticizers added to the composition to an extremely low rate. There is an effect that a moisture-curable composition is provided.

─────────────────────────────────────────────────── ─── Continuation of the front page (51) Int.Cl. ⁶ Identification code Internal reference number FI technical display area C09K 3/10 G

Claims (3)

[Claims] 1. A polyisocyanate compound, a compound having two or more silylthio groups in the molecule, calcium carbonate surface-treated with a fatty acid ester, and a compound represented by the general formula: (R ¹ is a hydrogen atom, a fluorine atom or a carbon number of 1 to 20.
Is a monovalent or divalent organic group, and is bonded to a silicon atom through a silicon-hydrogen bond or a silicon-carbon bond.
R ² is a monovalent or divalent organic group having 1 to 30 carbon atoms, Y is an oxygen atom or a nitrogen atom, n is 0,
It is an integer selected from 1, 2, and 3. ) Or (In the formula, R ³ , R ⁴ , R ⁵ , and R ⁷ each independently represent an atom or atomic group in the same range as R ^1, and R ⁶ represents an atom or atomic group in the same range as R ² . 1 and m are the number of repeating units, and n is O or a positive integer.) A moisture-curable type having excellent storage stability, containing a compound having at least one silyl ester group represented by the formula Composition. 2. 80 parts of calcium carbonate surface-treated with the fatty acid ester is added to 100 parts by weight of the total amount of the composition.
The moisture-curable composition having excellent storage stability according to claim 1, wherein the moisture-curable composition is contained in an amount of about 200 to 200% by weight. 3. Based on 100 parts by weight of calcium carbonate surface-treated with the fatty acid ester, the compound represented by the general formula: (R ¹ is a hydrogen atom, a fluorine atom or a carbon number of 1 to 20.
Is a monovalent or divalent organic group, and is bonded to a silicon atom through a silicon-hydrogen bond or a silicon-carbon bond.
R ² is a monovalent or divalent organic group having 1 to 30 carbon atoms, Y is an oxygen atom or a nitrogen atom, n is 0,
It is an integer selected from 1, 2, and 3. ) Or (In the formula, R ³ , R ⁴ , R ⁵ , and R ⁷ each independently represent an atom or atomic group in the same range as R ^1, and R ⁶ represents an atom or atomic group in the same range as R ² . 1 and m are the number of repeating units, and n is O or a positive integer.) Containing 0.1 to 10 parts by weight of a compound having at least one silyl ester group in the molecule. A moisture-curable composition having excellent storage stability according to claim 1 or 2.