JPH0313261B2 - - Google Patents

Description

[Detailed description of the invention]

[Technical Field of the Invention] The present invention relates to a composition that is suitable as a sealant composition and that can be cured at room temperature into a rubber-like elastic body when exposed to moisture, and relates to a rubber that has excellent adhesive properties, a high elongation rate, and is highly flexible. The present invention relates to a room temperature curable composition capable of forming a shaped elastic body. [Technical background of the invention and its problems] Polymers having hydrolyzable silicon functional groups and whose main chain is polyether are known (Japanese Patent Application Laid-Open No. 1983-1999).
156599, etc.). Room-temperature curable compositions based on this polymer have recently begun to be used as sealing materials for joints in buildings, joints in transportation machines, etc. (Japanese Unexamined Patent Publication No. 73998/1984, etc.). However, since this type of polymer does not inherently have adhesive properties, it is necessary to pre-treat the surface to be coated with a primer or add a silane coupling agent to the composition to improve its adhesive properties. It is necessary to grant. However, the addition of a silane coupling agent has the problem that, at the cost of obtaining adhesive properties, the elongation of the rubber-like elastic body after curing decreases, making it brittle. [Object of the Invention] The present invention is intended to solve these problems, and aims to provide a room-temperature curable composition that has excellent adhesive properties and can yield a rubber-like cured product with a high elongation rate. do. [Structure of the invention] That is, the present invention comprises (A) general formula or (In the formula, R ¹ and R ² are divalent hydrocarbon groups, R ³
and R ⁹ is a non-hydrolyzable divalent hydrocarbon group whose main chain consists only of C, N, S and O atoms and no adjacent heteroatoms, R ⁴
and R ¹⁰ is a monovalent hydrocarbon group, R ⁵ is a substituted or unsubstituted monovalent hydrocarbon group, R ⁶ and R ⁸ are hydrogen atoms or monovalent hydrocarbon groups, and R ⁷ is a divalent organic group. , X is a hydrolyzable group, a is a number from 1 to 3, m is a number from 10 to 500, n is a number from 6 to 500, k and j are numbers from 1 to 10, and the molecular weight of the copolymer is 1000.
Indicates a number chosen to be in the range ~50000. ) 100 parts by weight of a copolymer whose molecular chain ends are blocked with a hydrolyzable silyl group (B) 3 to 300 parts by weight of an inorganic filler (C) 0.001 to 20 parts by weight of a curing catalyst This invention relates to a room temperature curable composition. (A) General formula used in the present invention or (In the formula, R ¹ to R ¹⁰ , ^X , a, m, n, k, and j are as described above.) In the copolymer represented by A propylene unit or a combination system of oxyethylene units and oxypropylene units is preferable, as it is easy to obtain raw materials and polymerize.
Oxypropylene units are particularly preferred because they can easily maintain a liquid state even at a high degree of polymerization. The divalent hydrocarbon group of R ² is a methylene group,
Ethylene group, trimethylene group, tetramethylene group, phenylene group, cyclohexylene group and

Examples include groups represented by [Formula]. Among these groups, a methylene group is preferred from the viewpoint of easy availability of raw materials. R ³ and R ⁹ are non-hydrolyzable divalent hydrocarbon groups whose main chain consists only of C, N, S and O atoms and no adjacent heteroatoms, -CH ₂ - _Examples include O _{( -CH2 ) -3 , -CH2CH2OCH2CH2- ,} ( _-CH2CH2O ) _{-2CH2CH2- , -OCH2CH2-} , and the _like . Among these, a group represented by _-CH2 -O( _-CH2 ) _-3 (provided that a trimethylene group is bonded to a silicon atom) is preferred from the viewpoint of easy availability of raw materials. R ⁴ and R ¹⁰ are monovalent hydrocarbon groups; alkyl groups such as methyl, ethyl, propyl, butyl, hexyl; alkenyl groups such as vinyl and allyl; phenyl, tolyl, etc. Aryl group; examples include aralkyl groups such as β-phenylethyl group and β-phenylpropyl group, but methyl group and phenyl group are preferred from the viewpoint of ease of synthesis of raw materials, and methyl group is particularly preferred from the viewpoint of easy availability. preferable. R ⁵ is a substituted or unsubstituted monovalent hydrocarbon group, and in addition to those exemplified by R ⁴ and R ¹⁰ , hydroxyethyl group, 2-methoxyethyl group, ρ-
Examples include hydroxyphenyl group and ρ-chlorophenyl group. Among these, phenyl group and ρ-
Aromatic groups such as hydroxyphenyl groups are preferred. R ⁶ and R ⁸ are hydrogen atoms or monovalent hydrocarbon groups, and R ⁴ and R 8 are monovalent hydrocarbon groups.
Examples include those exemplified in ^R10 . Further, the divalent organic group of R ⁷ is preferably a divalent hydrocarbon group from the viewpoint of availability of raw materials and precursors and ease of synthesis, such as an ethylene group, a trimethylene group, a hexamethylene group, a cyclohexylene group, a phenylene group, biphenylene group,

Examples include [Formula]. In addition to these, phenylene groups, biphenylene groups, and

A divalent aromatic group such as [Formula] is preferred. The hydrolyzable group of
Examples include dialkylaminoxy groups, ketoxime groups, and alkenoxy groups, but methoxy groups, ethoxy groups, propoxy groups, and isopropoxy , alkoxy groups having 1 to 6 carbon atoms such as hexyloxy groups, and 2-methoxyethoxy groups are suitable, and methoxy groups and ethoxy groups are preferred from the viewpoint of high hydrolyzability (curing reactivity of the composition). A methoxy group is particularly preferred. The number a of hydrolyzable groups is selected within the range of 1 to 3, but it is preferable that a is 2 in order to obtain a composition that provides a rubber-like cured product with a high elongation rate. The degree of polymerization m of the oxyalkylene unit is selected in the range of 10 to 500, and if m is less than 10, a composition that provides a rubber-like cured product with a sufficient elongation rate at a viscosity below that which provides practical workability is selected. becomes difficult to obtain. On the other hand, if m is larger than 500, the adhesiveness, which is a feature of the present invention, decreases. The degree of polymerization n of the siloxane unit is selected within the range of 6 to 500. If n is smaller than 6, it becomes difficult to obtain a composition that provides a rubber-like cured product with a high elongation rate. Moreover, if n is larger than 500, the non-staining property and post-paintability of the composition after curing will be reduced. k and j are numbers from 1 to 10, and are selected so that the molecular weight of the copolymer is in the range of 1,000 to 50,000. If the molecular weight is less than 1,000, it will not be possible to obtain a composition that provides a rubber-like cured product with a high elongation rate, which is a feature of the present invention, and if it exceeds 50,000, the viscosity will increase and workability will decrease. The copolymer (A) used in the present invention has the following general formula: (In the formula, R ¹ and R ² are divalent hydrocarbon groups, m
indicates a number from 10 to 500. ) Polyoxyalkylene whose molecular chain end is blocked with an epoxy group, () General formula (In the formula, R ³ is a non-hydrolyzable divalent hydrocarbon group whose main chain consists only of C, N, S, and O atoms and has no adjacent heteroatoms; R ⁴ is a monovalent Hydrocarbon group, n represents a number from 6 to 500) A siloxane whose molecular chain end is blocked with an epoxy group, () General formula R ⁵ -NH ₂ (In the formula, R ⁵ is substituted or unsubstituted. represents a monovalent hydrocarbon group) or the general formula (In the formula, R ⁶ and R ⁸ are a hydrogen atom or a monovalent hydrocarbon group, and R ⁷ is a divalent organic group.) and a diamine compound represented by the general formula (In the formula, R ⁹ is a non-hydrolyzable divalent hydrocarbon group whose main chain consists only of C, N, S, and O atoms and has no adjacent heteroatoms; R ¹⁰ is a monovalent Hydrocarbon group, X is a hydrolyzable group, a is 1-
Shows the number 3. ) can be synthesized by reacting an epoxy group represented by () with an organosilicon compound having a hydrolyzable group. A typical example of () is one obtained by adding epichlorohydrin to polyoxyethylene or polyoxypropylene, both ends of which are blocked with hydroxyl groups, in the presence of a basic catalyst or the like. A typical example of () is obtained by adding allyl glycidyl ether to polydimethylsiloxane or polymethylphenylsiloxane in which both ends are blocked with hydrogen atoms bonded to silicon atoms in the presence of a platinum catalyst. Things can be mentioned. A typical example of () is CH ₃ (CH ₂ ) ₃ NH ₂ , CH ₃ (CH ₂ ) ₄ NH ₂ , CH ₂ = R ⁵ −NH ₂ .
CHCH ₂ NH ₂ , HO(CH ₂ ) ₂ NH ₂ ,

【formula】

【formula】

【formula】

[Formula] is H ₂ N(-CH ₂ )- ₂ NH ₂ ,

【formula】

【formula】

【formula】

【formula】

【formula】

〔Effect of the invention〕

The composition of the present invention is useful as a room temperature curable composition that provides a rubber-like cured product with excellent adhesiveness, high elongation rate, and high flexibility, does not cause staining due to adhesion of dust, and has good weather resistance. It is also excellent in
It is suitable as a sealing material for joints in external walls of buildings, joints in transportation machines, etc. [Example] The present invention will be explained below with reference to Examples. In addition, in the synthesis examples, examples, and comparative examples, all parts are parts by weight.
% indicates weight %. Synthesis Example 1 3 moles of glycidyl group-terminated polyoxypropylene with an average degree of polymerization of 15, a molecular weight of approximately 1000, and a viscosity of 270 cst at 25°C. 2 moles of siloxane represented by

[Formula] 6 mol and an amount of methanol corresponding to 10% of the total weight of polyoxypropylene and siloxane were added, and heating and stirring was started at 80° C. under a nitrogen atmosphere. A portion of the sample was taken out at 4 hour intervals from the start of heating and stirring, and the total amount of epoxy groups and primary amines in the sample was determined using potentiometric titration, and the viscosity at 25°C was also measured. 16 hours after the start of heating and stirring, the titration of epoxy groups and primary amines decreased by almost the theoretical amount, and the viscosity, which was 150cst before heating, reached 3600cst. 2 mol of was added, and heating and stirring was continued under the same conditions.
After adding the above silane, a sample was taken out at 4 hour intervals and the total amount of epoxy groups and primary amines in the sample was determined using potentiometric titration, and it was found that they almost disappeared within 12 hours after adding the silane. And again
Since the peak due to protons of epoxide methylene was no longer observed by NMR, heating and stirring was stopped, and methanol was distilled off to form a pale yellow viscous liquid with a viscosity of 18,000 cst at 25°C and a specific gravity of 1.01 at the same temperature (see below). A polymer represented by the formula was obtained. This polymer is hereinafter referred to as P-1. Synthesis Example 2 2 moles of glycidyl group-end-blocked polyoxypropylene used in Synthesis Example 1, with an average degree of polymerization of 50, a molecular weight of about 3000, and a viscosity of 970 cst at 25°C. 1 mol of siloxane represented by , 4 mol of n-butylamine, and phenol corresponding to 5% by weight based on the total weight of polyoxypropylene and siloxane were added, and heating and stirring was started at a temperature of 60°C under a nitrogen atmosphere. . A portion of the sample was extracted every 4 hours from the start of heating and stirring, and the total amount of epoxy groups and amines in the sample was determined using potentiometric titration. As a result, the titration of epoxy groups and amines reached 16 hours after the start of heating and stirring. The viscosity decreased by almost the theoretical amount, and when the viscosity was measured at 25°C, it reached 33,000 cst.
to this Adding 2 moles of an organosilicon compound represented by
Heating and stirring was continued under the same conditions. After adding the above silane, a portion was taken out every 4 hours and the total amount of epoxy groups and amines in the sample was determined using potentiometric titration, and it was found that they had almost disappeared 8 hours after the addition of the silane. Furthermore, as the peak due to protons of epoxide methylene was no longer observed by NMR, heating and stirring was stopped, and a pale yellow viscous liquid with a viscosity of 38,000 cst at a temperature of 25°C and a specific gravity of 1.01 at the same temperature (using the following formula) The following polymer) was obtained. This polymer is hereinafter referred to as P-2. Synthesis Example 3 2 moles of glycidyl group-terminated polyoxypropylene with an average degree of polymerization of 50, a molecular weight of about 3000, and a viscosity of 970 cst at 25°C. Add 2 moles of siloxane represented by, 5 moles of n-butylamine, and phenol equivalent to 3% by weight based on the total weight of polyoxypropylene and siloxane, and use tetrahydrofuran as a solvent under a nitrogen atmosphere at the solvent reflux temperature. Heating and stirring was started. After the start of heating and stirring, a portion was taken out every 4 hours and the total amount of epoxy groups and amines was measured using potentiometric titration. It was found that the titration of epoxy groups and amines was approximately 20 hours after the start of heating and stirring. decreased by the theoretical amount. After distilling off the solvent tetrahydrofuran, the viscosity at 25°C was measured and found to be 42,000 cst. to this Adding 2 moles of an organosilicon compound represented by
Heating and stirring was continued under the same conditions. After adding the above silane, a portion was taken out every 4 hours and the total amount of epoxy groups and amines in the sample was determined using potentiometric titration, and it was found that they almost disappeared 12 hours after the addition of the silane. Since the peak due to protons of epoxide methylene was no longer observed by NMR, the viscosity at 25℃ after heating and stirring was ended and the solvent tetrahydrofuran was distilled off.
A pale yellow viscous liquid (polymer represented by the formula below) with a specific gravity of 1.01 at 45,000 cst and the same temperature was obtained. Hereinafter, this polymer will be referred to as P-3. Synthesis Example 4 Same as used in Synthesis Example 1, average degree of polymerization 15,
3 moles of polyoxypropylene with a molecular weight of approximately 1000 and a viscosity of 270 cst at 25°C, both ends blocked with glycidyl groups, used in Synthesis Example 3. Added 3 moles of siloxane represented by 3 moles of ethylenediamine, 3% by weight of phenol based on the total weight of oxypropylene and siloxane, used tetrahydrofuran as a solvent, and started heating and stirring at the solvent reflux temperature under a nitrogen atmosphere. . After the start of heating and stirring, a portion was taken out every 4 hours and the total amount of epoxy groups and primary amines was determined using potentiometric titration. After 16 hours, the total amount of epoxy groups and primary amines was theoretically determined. It showed a decrease by almost the same amount as the value. After distilling off the solvent tetrahydrofuran, the viscosity at 25℃ is 38000 cst.
had reached. to this Adding 2 moles of an organosilicon compound represented by
Heating and stirring was continued under the same conditions. After adding the above silane, a portion was taken out every 4 hours and the total amount of epoxy groups and primary amines was determined using potentiometric titration method. After 12 hours, they almost disappeared. Since the peak due to epoxide methylene protons was no longer observed,
After heating and stirring, the viscosity at 25℃ is
A pale yellow viscous liquid (polymer expressed by the formula below) with a specific gravity of 1.01 at 41,000 cst and the same temperature was obtained. This polymer is hereinafter referred to as P-4. Examples 1 to 4 For 100 parts of the copolymer obtained in Synthesis Examples 1 to 4, the molecular chain ends of which were blocked with hydrolyzable silyl groups,
Fillers, inorganic pigments, and thixotropic agents shown in Table 1 were added and dispersed uniformly with a triple roll, and then the organic tin compounds shown in Table 1 were added and mixed to prepare samples 1 to 4. Obtained. These samples were cured into sheets approximately 2 mm thick, cured at room temperature for 14 days, and then punched into JIS No. 2 dumbbells, and the surface condition was observed by finger touch and a tensile test was performed. Then, in the same manner, the obtained dumbbell-shaped test piece was
Installed in a 150℃ dryer and weather meter,
After applying the deterioration conditions (heating and ultraviolet irradiation) for the period shown in Table 1, the state of the sample pieces was observed and a tensile test was conducted. These results are also shown in Table 1. Comparative example 1 Molecular weight approximately 8000, as a terminal group

Fillers, inorganic pigments, and thixotropic properties shown in Table 1 were added to 100 parts of polyoxypropylene having the formula, and the mixture was uniformly dispersed using three rolls. The indicated organic tin compound was added and mixed to obtain Sample 5. Using this sample 5, the same tests as in Examples 1 to 4 were conducted. The result is also the first
Shown in the table. Examples 5-8 Same samples 1-4 as those prepared in Examples 1-4
A shear adhesion test specimen shown in FIG. 1 was prepared using the following method. After curing the created test specimen at room temperature for 28 days,
A tensile test was conducted. The results are shown in Table 2. Comparative Example 2 Using the same sample 5 prepared in Comparative Example 1, a shear adhesion test specimen shown in FIG. 1 was prepared. The same tests as in Examples 5 to 8 were conducted using this test specimen. The results are also shown in Table 2.

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【table】

【table】 [Brief explanation of the drawing]

FIG. 1 shows a perspective view of a specimen subjected to a shear adhesion test. The unit in the figure is mm. 1... Sample, 2... Adherent (glass, aluminum or PVC steel plate).

Claims (1)

[Claims] 1 (A) General formula or (In the formula, R ¹ and R ² are divalent hydrocarbon groups, R ³
and R ⁹ is a non-hydrolyzable divalent hydrocarbon group whose main chain consists only of C, N, S and O atoms and no adjacent heteroatoms, R ⁴
and R ¹⁰ is a monovalent hydrocarbon group, R ⁵ is a substituted or unsubstituted monovalent hydrocarbon group, R ⁶ and R ⁸ are hydrogen atoms or monovalent hydrocarbon groups, and R ⁷ is a divalent organic group. , X is a hydrolyzable group, a is a number from 1 to 3, m is a number from 10 to 500, n is a number from 6 to 500, k and j are numbers from 1 to 10, and the molecular weight of the copolymer is 1000.
Indicates a number chosen to be in the range ~50000. ) 100 parts by weight of a copolymer whose molecular chain ends are blocked with a hydrolyzable silyl group (B) 3 to 300 parts by weight of an inorganic filler (C) 0.001 to 20 parts by weight of a curing catalyst A room temperature curable composition. 2. The composition according to claim 1, wherein R ¹ is an ethylene group and/or a propylene group. 3. The composition according to claim 2, wherein R ¹ is a propylene group. 4. The composition according to claim 1, wherein R ² is a methylene group. 5. The composition according to claim 1, wherein R ³ and R ⁹ are groups represented by -CH ₂ O(-CH ₂ )- ₃ (wherein a trimethylene group is bonded to a silicon atom). thing. 6. The composition according to claim 1, wherein R ⁴ and R ¹⁰ are methyl groups. 7. The composition according to claim 1, wherein R ⁷ is a divalent hydrocarbon group. 8. The composition of claim 1, wherein R ⁷ is a divalent aromatic group. 9. The composition according to claim 1, wherein X is an alkoxy group having 1 to 6 carbon atoms. 10. The composition of claim 1, wherein a is 2.