JPH0257822B2 - - Google Patents

Description

[Detailed description of the invention]

[Industrial Application Field] The present invention relates to a composition suitable as a sealant composition that can be cured at room temperature into a rubber-like elastic body when exposed to moisture, and in particular has excellent heat resistance and weather resistance, and has adhesive properties. The present invention relates to a room temperature curable composition which provides a rubber-like cured product that does not leave any sticky residue on the surface. [Prior art and problems] Polymers having hydrolyzable silicon functional groups and whose main chain is polyether are known (Japanese Patent Application Laid-open No. 1983-1979).
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. 73998/1983, etc.). However, this type of polymer has poor heat resistance and weather resistance, so it can be used in joints of external walls of buildings where weather resistance is required.
There is a problem in that it is not suitable for use in places where the temperature is relatively high, such as parts of joints in transportation machines. Furthermore, since this type of polymer does not inherently have adhesive properties, it is necessary to apply a primer treatment to the surface to which it is adhered before applying the sealant. Furthermore, since adhesiveness remains on the surface of the cured product, there is a problem in that dust tends to adhere to the sealant. [Means for Solving the Problems] The present invention is intended to solve these problems. An object of the present invention is to provide a room temperature curable composition that provides a cured product free of oxidation. That is, the present invention comprises (A) general formula; (In the formula, R ¹ and R ² are divalent hydrocarbon groups, A is a substituted or unsubstituted divalent aromatic group, and Z is

【formula】

【formula】

【formula】

[expression] or

Indicates a group represented by [Formula], where R ³ is an alkyl group having 1 to 6 carbon atoms,
R ⁴ is a monovalent hydrocarbon group, R ⁵ , R ⁷ , R ⁹ and
R ¹¹ is a substituted or unsubstituted divalent aromatic group,
R ⁶ , R ⁸ , R ¹⁰ and R ¹² are divalent hydrocarbon groups,
R ¹³ is a monovalent hydrocarbon group, a is a number of 1 to 3, m is a number of 10 to 500, and n is a number of 1 or more. ) and has a molecular weight of 500 to 50,000.
A room temperature curable composition characterized by comprising: 100 parts by weight of a polyether 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 relating to things. General formula of component A of the present invention; (wherein R ¹ , R ² , A, Z, m and n are as described above),
The oxyalkylene unit represented by R ¹ O is preferably an oxyethylene unit, an oxypropylene unit, or a combination system of oxyethylene units and oxypropylene units because it is easy to obtain raw materials and polymerize, and it is easy to maintain a liquid state even at a high degree of polymerization. Particularly preferred are oxypropylene units. The polymerization degree m of the oxyalkylene unit is selected in the range of 10 to 500. If m is smaller than 10, practical workability cannot be obtained;
If it is larger than 500, the heat resistance and weather resistance, which are the characteristics of the present invention, will deteriorate. 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. A is a substituted or unsubstituted divalent aromatic group, and has the following advantages: easy availability of raw materials, good compatibility with other raw materials, and workability of the room-temperature curable composition of the present invention. Since it has a good and sufficient elongation rate, it is expressed by a phenylene group, a biphenylene group, or the general formula: -R ¹⁴ -Q-R ¹⁵ - (wherein R ¹⁴ , R ¹⁵ and Q are as described above). It is preferable that it is a group. As a specific example of A,

【formula】 【formula】

【formula】

【formula】

【formula】

【formula】

【formula】

【formula】

【formula】

Examples include [Formula]. z is

【formula】

【formula】

【formula】

[expression] or

[Formula] (wherein R ³ to R ¹³ and a are as described above). Here, the alkyl group having 1 to 6 carbon atoms in R ³ is
A methyl group or an ethyl group is preferred because the alkoxy group bonded to the silicon atom represented by R ³ O- has high hydrolyzability. The number a of hydrolyzable groups is 1
-3, but preferably a is 2 in order to obtain a composition that provides a rubber-like cured product with a high elongation rate. The monovalent hydrocarbon group for R ⁴ can be selected from alkyl groups, aryl groups, aralkyl groups, etc., but a methyl group is recommended from the viewpoint of ease of synthesis and raw material availability. R ⁵ , R ⁷ , R ⁹ and R ¹¹ are substituted or unsubstituted divalent aromatic groups, and a substituted or unsubstituted phenylene group is preferred from the viewpoint of availability of raw materials and ease of synthesis. Also, R ⁶ , R ⁸ , R ¹⁰ and
R ¹² is a divalent hydrocarbon group, and methylene, ethylene, trimethylene, and tetramethylene groups are preferred from the viewpoint of ease of synthesis of raw materials and precursors, and balance of chemical stability and ease of synthesis. Among these, a trimethylene group is particularly preferred. On the other hand, as Z

[Formula] (In the formula, R ³ , R ⁴ , R ¹² , R ¹³ and a are as described above.) If heat resistance and weather resistance are important, R ¹³ may be selected from aryl groups. Preferred, R ¹³ if no surface tack residue is important
is preferably selected from an alkyl group or an alkenyl group. A specific example of such Z is etc. Further, n is a number greater than or equal to 1, and may be 1, but must be selected so that the molecular weight of the polyether, component (A) of the present invention, is in the range of 500 to 50,000.
If the molecular weight is less than 500, the elongation rate of the cured elastic body will not reach that required for a sealing material, while if it is more than 50,000, the viscosity will increase and workability will decrease. The polyether which is the component (A) of the present invention has, for example, the general formula (); (In the formula, R ¹ , R ² and m are as described above.) Polyoxyalkylene () whose molecular chain terminal is blocked with an epoxy group General formula: H ₂ N-A-NH ₂ (In the formula, A is as mentioned above.)
An aromatic diamine compound represented by, and () general formula; (In the formula, R ³ , R ⁴ and a are X
are −R ⁵ −NH ₂ , −R ⁶ −O−R ⁷ −NH ₂ , −R ⁸ −
NH−R ⁹ −NH ₂ , −R ¹⁰ −S−R ¹¹ −NH ₂ or

[Formula] is shown. However, R ⁵ to R ¹³ are as described above. ) can be synthesized by reacting an amino 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. () Specific examples of ingredients include:

【formula】

【formula】

【formula】

【formula】

【formula】

etc. Also, as a specific example of () etc. The polyether which is component (A) of the present invention is obtained by the reaction of the epoxy group of () described above with the amino group of () and (). The reactions of (), () and () are preferably carried out at a temperature higher than the ambient temperature, for example 50 to 150°C. In this case, it is preferable to use alcohol or phenol as an accelerator. Methanol is one of the preferred ones;
There is no need to use a solvent when carrying out this reaction, but
A hydrocarbon-based, ether-based, or ester-based solvent may be used. The amounts of (), () and () are theoretically determined by the molar ratio ():():()=(n+1):
n:2. However, in reality, there is no problem even if () and () are used in an amount slightly exceeding the theoretical amount. As for the reaction procedure, (), () and () may be added and reacted at the same time, but first, () and an amount less than its equivalent and an amount suitable for obtaining a polyether having the above molecular weight range are added. It is easier to control the degree of polymerization by reacting with () to extend the chain, and then adding and reacting with () in the required amount or a slightly larger amount. A functional group can be introduced. Component (B) of the present invention is a component for imparting appropriate non-flowability and reinforcing properties to the composition of the present invention. These (B) components include fumed silica, precipitated silica, ground silica, diatomaceous earth, calcium carbonate,
Examples include titanium oxide, alumina, aluminum hydroxide, iron oxide, talc, and clay. The amount of component (B) used is in the range of 3 to 300 parts by weight, preferably 5 to 200 parts by weight, per 100 parts by weight of component (A). If the amount of component (B) is less than 3 parts by weight, non-fluidity and reinforcing properties cannot be obtained, and if it is more than 300 parts by weight, the viscosity of the composition increases and workability decreases. The curing catalyst (C) used in the present invention includes tin carboxylates such as tin octylate; organic tin carboxylates such as dibutyltin dilaurate, dibutyltin dimaleate, and dibutyltin phthalate; organic tin oxides and their esters; Reactants; organic titanate esters such as tetrabutyl titanate; amines; amine salts; quaternary ammonium salts; guanidine compounds, etc. are exemplified. These curing catalysts are 0.001 to 100 parts by weight of component (A).
It is preferable to use it in a range of 20 parts by weight. If the amount of component (C) is less than this, the curing speed will be too slow and it will be unsuitable for use, whereas if it is more than this, it will not only be meaningless but also undesirable because there is a risk of exudation or precipitation. Since the compositions of the present invention are inherently adhesive, there is no need to use commonly used silane coupling agents to impart adhesion, but they can be used to further enhance adhesion. Alternatively, hydrolyzable silanes including these may be added for the purpose of enabling long-term storage in one package. These hydrolyzable silanes include _H2N ( _CH2 ) _3Si ( _OCH3 ) ₃ , _H2N ( _CH2 ) _3Si ( _OCH2CH3 ) _{3 , H2N} ( _CH2 ) _3NH ( _CH2 ) _3Si ( _OCH3 ) ₃ , _CH2 = CHSi( _{OCH2CH3 ) 3} , ( _CH3 ) _2Si (OCH3) ₂ , _CH3Si ( _OCH3 ) ₃ , _{CH3Si ( OCH2CH3 ) 3} , Si( _{OCH2CH3 )} ) ₄ etc. are examples. In order to obtain long-term storage stability in a single package, it is also effective to add a monohydric primary alcohol such as methanol or ethanol. Furthermore, a thixotropic agent such as hydrogenated castor oil and a plasticizer such as dioctyl phthalate, butylbenzyl phthalate, or chlorinated paraffin can also be used in the composition of the present invention. The composition of the present invention can be used in a single package as described above, or it can be stored separately into two components, for example, a component consisting of components (A) and (B), and a component (C). It is also possible to prepare two packages in which the two are mixed together before use. [Effects of the Invention] The composition of the present invention has excellent heat resistance and weather resistance, has adhesive properties, and has no residual surface adhesiveness, so staining due to adhesion of dust does not occur, and it can be used at joints on external walls of buildings. It is suitable as a sealing material for areas where weather resistance is required, such as in areas such as the United States, and areas that are exposed to relatively high temperatures, such as parts of joints in transportation machines. [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 weight and %.
indicates weight %. Synthesis Example 1 For 10 epoxy equivalents of glycidyl-terminated polyoxypropylene with an average degree of polymerization of 15, a molecular weight of about 1000, and a viscosity of 270 cSt at 25°C,

4 moles of [Formula] and methanol in an amount equivalent to 10% of polyoxypropylene were added, and heating and stirring was started at 60°C under a nitrogen atmosphere. A portion was extracted 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.
The viscosity at 25°C was also measured. 16 hours after the start of heating and stirring, the titration of the epoxy group and the primary amine decreased by almost the theoretical amount, and the viscosity, which was 100cSt before the start of heating and stirring, reached 1500cSt.

Two moles of [Formula] were added, and heating and stirring was continued under the same conditions. A portion of the silane was sampled at 4-hour intervals after the addition of the silane, and the total amount of epoxy groups and primary amines in the sample was determined using potentiometric titration. almost disappeared,
Also, the peak due to the proton of epoxide methylene by NMR (based on tetomethylsilane)
2.67 ppm) was no longer observed, so heating and stirring was stopped, and methanol was distilled off to form a pale yellow viscous liquid with a viscosity of 15,000 cSt at 25°C and a specific gravity of 1.01 at the same temperature (hydrolysis expressed by the following formula). A polyether whose molecular chain ends were blocked with a silyl group was obtained. Hereinafter, this product will be referred to as P-1. An attempt was made to acetylate a small amount of the tertiary amine in a mixture of acetic anhydride and glacial acetic acid (9:1), and titrate the unacetylated tertiary amine with perchloric acid and glacial acetic acid using crystal violet as an indicator. Only a trace amount was observed. Synthesis Example 2 For 10 epoxy equivalents of glycidyl group-end-blocked polyoxypropylene with an average degree of polymerization of 32, a molecular weight of approximately 2000, and a viscosity of 550 cSt at 25°C,

4 moles of [Formula] and methanol in an amount equivalent to 10% of polyoxypropylene were added, and heating and stirring was started at 60°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 the epoxy group and the primary amine decreased by almost the theoretical amount, and the viscosity, which was 230 cSt before the start of heating and stirring, reached 3900 cSt.

Two moles of [Formula] were added, and heating and stirring was continued under the same conditions. A portion of the silane was sampled at 4-hour intervals after the addition of the silane, and the total amount of epoxy groups and primary amines in the sample was determined using potentiometric titration. almost disappeared,
In addition, as the peak due to protons of epoxide methylene was no longer observed by NMR, heating and stirring was terminated, and methanol was distilled off to form a pale yellow viscous liquid with a viscosity of 26,000 cSt at 25°C and a specific gravity of 1.01 at the same temperature (see below). Polyether whose molecular chain ends are blocked with a hydrolyzable silyl group represented by the formula)
I got it. Hereinafter, this product will be referred to as P-2. Incidentally, using a small amount of the tertiary amine, titration of the tertiary amine was attempted in the same manner as in Synthesis Example 1, but only a very small amount was observed. Synthesis Example 3 For 6 epoxy equivalents of glycidyl group-terminated polyoxypropylene with an average degree of polymerization of 50, a molecular weight of approximately 3000, and a viscosity of 970 cSt at 25°C,

2 moles of [Formula] and methanol in an amount corresponding to 10% of polyoxypropylene were added, and heating and stirring was started at 60°C under a nitrogen atmosphere. A portion of the sample was taken out at 6 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. 18 hours after the start of heating and stirring, the titration of the epoxy group and the primary amine decreased by almost the theoretical amount, and the viscosity, which was 390 cSt at the start of heating and stirring, reached 4100 cSt. 2 mol of was added and heating and stirring was continued under the same conditions. A portion of the silane was sampled at 4-hour intervals after the addition of the silane, and the total amount of epoxy groups and primary amines in the sample was determined using potentiometric titration. The mixture almost disappeared, and the peak of epoxide methylene was no longer observed by NMR, so heating and stirring was stopped.
After methanol is distilled off, the viscosity at 25℃ is
A pale yellow viscous liquid (polyether whose molecular chain ends are blocked with hydrolyzable silyl groups represented by the following formula) with a specific gravity of 34,000 cSt and 1.01 at the same temperature was obtained. Hereinafter, this product will be referred to as P-3. Incidentally, using a small amount of the tertiary amine, titration of the tertiary amine was attempted in the same manner as in Synthesis Example 1, but only a very small amount was observed. Synthesis Example 4 For 10 epoxy equivalents of the same glycidyl group-terminated polyoxypropylene used in Synthesis Example 2, 4 moles of diaminodiphenyl ether used in Synthesis Example 2 and equivalent to 10% of the polyoxypropylene were added. An amount of methanol was added thereto, and the mixture was heated and stirred at 60° C. for 16 hours under the same conditions as in Synthesis Example 2, that is, under a nitrogen atmosphere. Then,

2.2 mol of [Formula] was added, and heating and stirring was continued under the same conditions. After adding the above silane, a portion was taken out at 4 hour intervals and the peak due to protons of epoxide methylene was observed by NMR.
After 12 hours, the peak disappeared, so heating and stirring was stopped, and methanol was distilled off to form a pale yellow viscous liquid with a viscosity of 21,000 cSt at 25°C and a specific gravity of 1.01 at the same temperature (hydrolyzable liquid expressed by the following formula). (Polyether whose molecular chain ends are blocked with silyl groups)
I got it. Hereinafter, this product will be referred to as P-4. Synthesis Example 5 For 10 epoxy equivalents of the same glycidyl group-terminated polyoxypropylene used in Synthesis Example 1, 4 moles of diaminodiphenyl ether used in Synthesis Example 1 and equivalent to 10% of the polyoxypropylene were added. The mixture was heated and stirred at 60° C. for 16 hours under the same conditions as in Synthesis Example 1, that is, under a nitrogen atmosphere. Then,

3 mol of [Formula] was added, and heating and stirring was continued under the same conditions. A portion of the silane was extracted at 4-hour intervals after the above silane was added, and the epoxy groups in the sample were quantified using potentiometric titration. As a result, the epoxy groups in the sample almost disappeared 16 hours after the addition of the silane, and the protons of epoxide methylene were determined by NMR. Since no peak was observed, heating and stirring was stopped, and methanol was distilled off to form a viscous liquid with a viscosity of 12,000 cSt at 25°C and a specific gravity of 1.01 at the same temperature (with a hydrolyzable silyl group represented by the following formula). A polyether (with molecular chain ends blocked) was obtained. Hereinafter, this product will be referred to as P-5. Examples 1 to 5 Polyethers (P-1 to 5) whose molecular chain ends were blocked with hydrolyzable silyl groups obtained in Synthesis Examples 1 to 5
To 100 parts, the filler, inorganic pigment, and thixotropic agent shown in Table 1 were added and uniformly dispersed with a triple roll, and then the organic tin compound also shown in Table 1 was added and mixed. , samples-1 to 5
I got it. These samples were cured into sheets with a thickness of about 2 mm, cured at room temperature for 14 days, and then punched into JIS No. 2 dumbbells, and the surface conditions were observed by finger touch and a tensile test was performed. Next, the dumbbell-shaped sample piece obtained in the same manner was placed in a 150°C dryer and a weather meter, and after applying the deterioration conditions (heating and ultraviolet irradiation) for the period shown in Table 1, the state of the sample piece was observed. Table 1 also shows the results of a tensile test. 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 uniformly dispersed with a triple roll.
Similarly, the organic tin compounds shown in Table 1 were added and mixed to obtain Sample-6. Example 1 using sample-6
The same test as in 5 was conducted. The results are also shown in Table 1. Examples 6-10 Same samples-1-1 as those prepared in Examples 1-5
A shear adhesion test specimen shown in FIG. 1 was prepared using No. 5. After curing the prepared test specimens 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 6 as prepared in Comparative Example 1, a shear adhesion test specimen shown in FIG. 1 was prepared. The same tests as in Examples 6 to 10 were conducted using this test specimen. The results are also shown in Table 2.

【table】

【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 and PVC steel plate).

Claims (1)

[Claims] 1 (A) General formula; (In the formula, R ¹ and R ² are divalent hydrocarbon groups, A is a substituted or unsubstituted divalent aromatic group, and Z is [formula] [formula] [formula] [formula] or [formula] represents a group, where R ³ is an alkyl group having 1 to 6 carbon atoms,
R ⁴ is a monovalent hydrocarbon group, R ⁵ , R ⁷ , R ⁹ and
R ¹¹ is a substituted or unsubstituted divalent aromatic group,
R ⁶ , R ⁸ , R ¹⁰ and R ¹² are divalent hydrocarbon groups,
R ¹³ is a monovalent hydrocarbon group, a is a number of 1 to 3, m is a number of 10 to 500, and n is a number of 1 or more. ) and has a molecular weight of 500 to 50,000,
A room temperature curable composition characterized by comprising: 100 parts by weight of a polyether 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 thing. 2. The composition according to claim 1, wherein R ⁵ , R ⁷ , R ⁹ and R ¹¹ are substituted or unsubstituted phenylene groups. 3 A is a substituted or unsubstituted phenylene group, a biphenylene group, or the general formula; -R ¹⁴ -Q-R ¹⁵ - (wherein R ¹⁴ and R ¹⁵ are substituted or unsubstituted phenylene groups, Q is an alkylene group, The composition according to claim 1, which is a divalent aromatic group represented by -O-, S- or [Formula]. 4. The composition according to claim 1, wherein Z is a group selected from [Formula] [Formula] [Formula] and [Formula] (wherein a and R ³ to R ¹¹ are as described above) thing. 5 The oxyalkylene unit R ¹ O is an oxyethylene unit, an oxypropylene unit, or a combination system of an oxyethylene unit and an oxypropylene unit,
A composition according to claim 1. 6. The composition according to claim 5, wherein the oxyalkylene unit is an oxypropylene unit. 7. The composition according to claim 1, wherein R ³ is a methyl group or an ethyl group. 8. The composition of claim 1, wherein R ² is a methylene group. 9. The composition of claim 1, wherein a is 2.