JPS62283123A - Polyether having molecular chain end blocked with hydrolyzable silyl group and production thereof - Google Patents

Abstract

PURPOSE:To obtain the titled polyether having excellent heat resistance and weather resistance and high adhesivity and capable of giving a cured rubbery material, by reacting a specific polyoxyalkylene with an aromatic diamine and an organic silicon compound having epoxy group and hydrolyzable group. CONSTITUTION:The objective polyether having molecular chain terminal blocked with a hydrolyzable silyl group of formula IV (n is >=1) can be produced by reacting (A) a polyoxyalkylene of formula I (R<1> and R<2> are bivalent hydrocarbon group; m is 10-500) having epoxy group at molecular chain terminal, (B) an aromatic diamine compound of formula II (A is bivalent aromatic residue) and (C) an organic silicon compound of formula III (R<3> and R<4> are bivalent hydrocarbon group; R<5> is univalent hydrocarbon group; R<6> is 1-6C alkyl; a is 1-3) having an epoxy group and a hydrolyzable group.

Description

Detailed Description of the Invention [Technical Field of the Invention] The present invention relates to polyethers whose molecular chain ends are blocked with hydrolyzable silyl groups and which can be cured at room temperature into a rubber-like elastic body when exposed to moisture. Regarding the production method, it is particularly useful as a base polymer for a room-temperature-curable composition that yields a gel-like cured product that has excellent heat resistance and weather resistance, has adhesive properties, and does not leave any sticky residue on the surface. This invention relates to polyether and its manufacturing method.

[Technical background of the invention and its problems]

Polymers having hydrolyzable silicon functional groups and having a polyether main chain are known (Japanese Patent Laid-Open No. 50-156599).
Publications, etc.). In recent years, room-temperature-curable compositions based on this polymer have begun to be used as sealing materials for joints in buildings and joints in transportation machinery (Japanese Patent Laid-Open No. 52-73
998, etc.).

However, this type of polymer has poor heat resistance and weather resistance, so it is not suitable for use in areas that are exposed to relatively high temperatures, such as joints in the exterior walls of buildings that require weather resistance, and parts of transportation machine joints. There is a problem.

Furthermore, since this type of polymer does not have adhesive properties due to its woody nature, 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.

[Purpose of the invention]

The present invention is intended to solve these problems, and provides a rubber-like cured product that has excellent heat resistance and weather resistance, has adhesive properties, and does not leave any sticky residue on the surface. The object of the present invention is to provide a polyether whose molecular chain ends are blocked with a hydrolyzable silyl group, which can be used as a base polymer in a curable composition, and a method for producing the same.

[Structure of the invention]

That is, the present invention has a general formula; , A is a substituted or unsubstituted divalent aromatic group, a
represents a number from 1 to 3, m represents a number from 10 to 500, and n represents a number from 1 to 500. ) and has a molecular weight of 500 to 50,000, a polyether whose molecular chain ends are blocked with a hydrolyzable silyl group, and (A) general formula; (wherein R1 and R2 are divalent Hydrocarbon group, m is 1° to 5
Indicates the number of 00. ) Polyoxyalkylene (B,) whose molecular chain terminal is blocked with an epoxy group General formula: 11□N-A-Nll2 (wherein A represents a substituted or unsubstituted divalent aromatic group ) and (C) general formula; (wherein, R3 and R4 are divalent hydrocarbon groups, R5 is 1
a valent hydrocarbon group, R6 is an alkyl group having 1 to 6 carbon atoms, a
represents a number from 1 to 3. ) A general formula characterized by reacting an epoxy group represented by the following with an organosilicon compound having a hydrolyzable group; R'l-a (R60)-5i-R'-0-R'-C) IC1b f
Nll-A-NH-CHzCII-R2-OHR'0)
r0HOH -l? ”-CHCHZ)-Ni1-A-Nll-CH
zCH-R3-0-R'-S i (OR6).

0H01l (wherein, pl, R2, R3 and R4 are divalent hydrocarbon groups, R5 is a monovalent hydrocarbon group, R6 is an alkyl group having 1 to 6 carbon atoms, A is a substituted or unsubstituted divalent hydrocarbon group, aromatic group,
a represents a number from 1 to 3, m represents a number from 10 to 500, and n represents 1
Indicates the above number. ) The present invention relates to a method for producing a polyether having a molecular weight of 500 to 50,000 and whose molecular chain ends are blocked with a hydrolyzable silyl group.

General formula of the present invention; % formula %: (wherein R', R2, R'', R', R5, R6+A, a
, m and n are as described above. ) In the polyether represented by 1, the oxyalkylene unit represented by R'0 is preferably an oxyethylene unit, an oxypropylene unit, or a combination system of an oxyethylene unit and an oxypropylene unit, since raw materials are easy to obtain and polymerize, and high polymerization is possible. Oxypropylene units are particularly preferred because they can easily maintain their liquid state even at low temperatures. The degree of polymerization m of the oxyalkylene unit is selected in the range of 10 to 500, and if m is smaller than IO, a polyether that provides a rubber-like cured product with a sufficient elongation rate at a viscosity below that for practical workability is selected. becomes difficult to obtain. On the other hand, if m is larger than 500, the heat resistance and weather resistance, which are the characteristics of the present invention, will decrease.

The divalent hydrocarbon group for R2 includes a methylene group, an ethylene group, a trimethylene group, and a tetramethylene group. Among these groups, a methylene group is preferred from the viewpoint of easy availability of raw materials.

Examples of R3 and R4 include those similar to R2, but R3 is preferably a methylene group from the viewpoint of easy availability of raw materials. Further, R4 is preferably a trimethylene group or a tetramethylene group from the viewpoint of ease of synthesis and availability of raw materials, and particularly preferably a trimethylene group.

The monovalent hydrocarbon group of R5 is an alkyl group such as a methyl group, an ethyl group, or a propyl group; an aryl group such as a phenyl group;
It can be selected from aralkyl groups such as β-phenylethyl group and β-phenylpropyl group, but methyl group or phenyl group is preferable from the viewpoint of ease of synthesis and raw material availability.
A methyl group is particularly preferred. The alkyl group having 1 to 6 carbon atoms in R6 is preferably a methyl group or an ethyl group, and a methyl group is particularly preferable, since the alkoxy group bonded to the silicon atom represented by R'O- is highly hydrolyzable. The number a of hydrolyzable groups is selected in the range of 1 to 3, but in order to obtain a polyether suitable as a base polymer for a composition that provides a rubber-like cured product with a high elongation rate, a must be 2. is preferred.

A is a substituted or unsubstituted divalent aromatic group, the raw material is easily available, and the compatibility with other raw materials is good;
And since the room-temperature curable composition using the polyether of the present invention has good workability and sufficient elongation after curing, phenylene group, bisphenylene group or general formula; -R'-Q- It is preferably a group represented by R'- (in the formula, R', R8OyohiQ, as shown in the previous '11f)).

C.I.

etc.

Further, n is a number of 1 or more, and may be 1, but must be selected so that the molecular weight of the polyether of the present invention is in the range of 500 to 50,000. When the polyether of the present invention is used as a base polymer for a sealant, if the molecular weight is less than 500, the elongation of the cured elastic body will not reach that required for the sealant; If it is too large, the viscosity will increase and workability will decrease.

The polyether of the present invention is, for example, (A) a polyoxyalkylene (B) whose molecular chain terminal is blocked with an epoxy group, represented by the general formula: General formula; ) 12N-A-NHK (wherein A is as described above).

), and (C) general formula; It can be synthesized by reacting a group with an organosilicon compound having a group.

A typical example of (A) 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 component (B) include CH3 Specific examples of component (C) include γ-glycidoxypropyltrimethoxysilane, γ-glycidoxybutyltrimethoxysilane, T-glycidoxy Propyltriethoxysilane, r-glycidoxybutyltriethoxysilane, methyl(T-glycidoxypropyl)dimethoxysilane, methyl(T-glycidoxybutyl)dimethoxysilane, methyl(γ-glycidoxypropyl)jet Toxysilane, methyl (T-glycidoxybutyl) jetoxysilane, phenyl (T-glycidoxypropyl) dimethoxysilane, phenyl (γ-glycidoxybutyl) dimethoxysilane, dimethyl (γ-glycidoxypropyl)
Methoxysilane, dimethyl (γ-glycidoxybutyl)
Examples include methoxysilane.

The polyether of the present invention can be obtained by reacting the epoxy groups (8) and (C) described above with the amino group (B).

The reactions of (A), (B) and (C) are preferably carried out at a temperature higher than the ambient temperature, for example 50 to 150°C. In this case, compounds such as methanol, ethanol, phenol, salicylic acid and tris(dimethylaminomethyl)phenol are preferably used as reaction promoters. Methanol is one of the preferred ones. Although it is not necessary to use a solvent when carrying out this reaction, a hydrocarbon-based, ether-based, or ester-based solvent may be used.

The amount of (A), (B) and (C) to be blended is theoretically such that the molar ratio is (A):(B):(C) =n:(n+1)
:2.

However, in reality, it is acceptable to use (B) and (C) in amounts slightly exceeding the theoretical amounts.

The reaction procedure includes (A), (B) and (
(8) may be added and reacted at the same time, but first, (8) and (B) in an amount exceeding its equivalent and in an amount suitable for obtaining a polyether having the above molecular weight range are reacted to elongate the chain. It is easier to control the degree of polymerization and to reliably introduce a hydrolyzable group to the end of the molecular chain by adding (C) in the required amount or slightly more than the required amount after the reaction.

〔Effect of the invention〕

A sealing material can be obtained by adding a curing catalyst such as an organotin compound, a filler, and the like to the polyether of the present invention. By using the polyether of the present invention as a base polymer, it has excellent heat resistance and weather resistance, and exhibits adhesion without the need for primer treatment on the surface to be adhered.Also, since there is no residual surface tackiness, it is difficult to prevent dust from adhering to the surface. A sealing material that does not cause staining can be obtained.

〔Example〕

Hereinafter, the present invention will be explained in more detail with reference to Examples.

In the Examples, Comparative Examples, and Reference Side, all parts are by weight, and % is by weight.

Example 1 Methanol in an amount equivalent to 10% of the oxypropylene was added to 10 epoxy equivalents of glycidyl group-end-blocked polyoxypropylene with an average degree of polymerization of 15 and a molecular weight of about 1,000.25°C and a viscosity of 270 cSt. , heating stirring was started at 60° C. under a nitrogen atmosphere. A portion of the sample 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.
Peak due to proton of epoxide methylene by NMR (2.67 ppm based on tetramethylsilane)
were observed, and the viscosity was measured at 25°C.

16 hours after the start of heating and stirring, the epoxy group and the first
The titration amount with the grade amine decreased by almost the theoretical amount, and at the same time the peak due to the proton of epoxide methylene disappeared.
The viscosity, which was 100 cSt before heating and stirring, decreased to 1
, 800 cS t reached, 7': TACH3, C112CH-C112-0-(CI(z)r-5
2.2-E/L/i(OCHt)z was added, and heating and stirring was continued under the same conditions. After adding the above silane
A portion was sampled at time intervals, and potentiometric titration was used to quantify the total amount of epoxy groups and primary amines in the sample.
When we observed the proton peaks of epoxide methylene by MR, they all almost disappeared 12 hours after the addition of silane, so we stopped adding DPpl and distilled off the methanol to reduce the viscosity at 25°C to 19.
,0OOC5L, specific gravity at the same temperature is 1.01, G
A pale yellow viscous liquid (polyether whose molecular chain ends were blocked with hydrolyzable silyl groups represented by the following formula, P-1) with a number average molecular weight of 6.500 as measured by PC was obtained.

CH.

OHO1+ Example 2 Polyoxypropylene with average polymerization degree of 32 and molecular weight of about 2,000.25°C and viscosity of 550 cSt. Glycidyl group end-blocked polyoxypropylene 1o For epoxy equivalent, methanol was added in an amount equivalent to 10% of xypropylene. In addition, heating and stirring was started at 60"C under a nitrogen atmosphere. A portion 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 method. ,
The proton peak of epoxide methylene was observed by NMR, and the viscosity at 25°C was 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 at the same time, the peak due to the proton of epoxide methylene disappeared, and the viscosity, which was 250 cSt before starting the heating and stirring, decreased. 4,
Since it reached 200cS t, CII□Cl1-C11
□-0-(CHz)-TS i (OCtl□C1l:
1): 2.2 mol of 1 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 total amount of epoxy groups and primary amines in the sample was determined using potentiometric titration, and the peak due to protons of epoxide methylene was observed using NMR. However, 12 hours after the addition of the silane, all of them had almost disappeared, so heating and stirring was ended, and the methanol was distilled off. A pale yellow viscous liquid having a number average molecular weight of 11.000 (polyether P-2 whose molecular chain ends were blocked with a hydrolyzable silyl group represented by the following formula) was obtained.

Example 3 Methanol in an amount equivalent to 10% of pyrene was added to 6 epoxy equivalents of glycidyl group-end-blocked polyoxypropylene with an average degree of polymerization of 50 and a molecular weight of about 3,000.25°C and a viscosity of 970 cSt. 60 at the bottom
Heating and stirring was started at ℃.

A portion 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, the peak due to protons of epoxydomethylene was observed by NMR, and the temperature was kept at 25°C. The viscosity was measured. 18 hours after the start of heating and stirring, the appropriate amounts of epoxy groups and primary amines decreased by almost the theoretical amount, and at the same time the peak due to protons of epoxide methylene disappeared, and the viscosity, which was 400 cSt before starting stirring, decreased to 5. , 200cSt, CII□CII
Added 2.2 mol of -CIt When we determined the total amount of epoxy groups and primary amines in the sample using a method and observed peaks due to protons of epoxide methylene using NMR, they almost disappeared 12 hours after the addition of silane. After the methanol was distilled off, the viscosity at 25°C was 25,000 cSt, and the specific gravity at the same temperature was 1.0.
1. Number average molecular weight measured by GPC is 9.500
A pale yellow viscous liquid (polyether whose molecular chain ends are blocked with hydrolyzable silyl groups represented by the following formula, P-3)
) was obtained.

OH0H OHO1l Reference Reference-1 to 3 Fillers shown in Table 1 to 100 parts of polyether (P-1 to 3) whose molecular chain ends are blocked with hydrolyzable silyl groups obtained in Examples 1 to 3. After adding the inorganic pigment and the thixotropic property imparting agent and uniformly dispersing them using a triple roll, the organic tin compounds shown in Table 1 were added and mixed to obtain Samples 1 to 3. These samples were cured into sheets with a thickness of about 21 mm, cured at room temperature for 14 days, and then punched into JIS No. 2 Danhers, and the surface condition was observed by finger touch and a tensile test was conducted. Next, the dumbbell-shaped sample piece obtained in the same manner was placed in a 150°C dryer and a weatherometer, and after applying the deterioration conditions (heating and ultraviolet irradiation) shown in Table 1, the shape of the sample piece was determined. B observation and tensile test were conducted. These results are also shown in Table 1.

Comparative Example 1 Molecular weight approximately 8,000, terminal group (CIIJ) zSi-C1lzCHzCII□-0-
For 100 parts of polyoxypropylene having
After adding the fillers, inorganic pigments, and thixotropic properties shown in the table and uniformly dispersing them with a triple roll, the organic tin compounds also shown in Table 1 were added and mixed.
I got 4. Tests similar to Reference Examples 1 to 3 were conducted using Sample-4. The results are also shown in Table 1.

Reference Examples 4 to 6 Using the same samples 1 to 3 as those prepared in Reference Examples 1 to 3, shear adhesion test specimens shown in FIG. 1 were created. After curing the prepared 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 4 as prepared in Comparative Example 1, a shear adhesion test specimen shown in FIG. 1 was prepared.

Tests similar to Reference Examples 4 to 6 were conducted using this test specimen. The results are also shown in Table 2.

[Brief explanation of drawings]

FIG. 1 shows a perspective view of a specimen subjected to a shear adhesion test. Note that the unit in the figure is ll1ffi. l...Sample

Claims (1)

[Claims] 1 General formula; ▲There are mathematical formulas, chemical formulas, tables, etc.▼ (In the formula, R^1, R^2, R^3 and R^4 are divalent hydrocarbon groups, R^5 is a monovalent hydrocarbon group, R^6 is an alkyl group having 1 to 6 carbon atoms, A is a substituted or unsubstituted divalent aromatic group, a is a number of 1 to 3, and m is 10 to 500 , n is a number of 1 or more), and the molecular weight is 5.
00 to 50,000, a polyether whose molecular chain ends are blocked with a hydrolyzable silyl group. 2. The polyether according to claim 1, wherein R^1 is an ethylene group and/or a propylene group. 3 Claim 2, in which R^1 is a propylene group
Polyether as described in Section. 4. The polyether according to claim 1, wherein R^2 is a methylene group. 5. The polyether according to claim 1, wherein R^6 is a methyl group or an ethyl group. 6 A is a substituted or unsubstituted phenylene group, biphenylene group or general formula; -R^7-Q-R^8- (wherein R
^7 and R^8 are substituted or unsubstituted phenylene groups,
Q represents an alkylene group, -O-, -S-, -SO_2- or -CO-. ) The polyether according to claim 1, which is a divalent aromatic group represented by: 7. The polyether according to claim 1, wherein a is 2. 8 (A) General formula; ▲There are mathematical formulas, chemical formulas, tables, etc.▼ (In the formula, R^1 and R^2 are divalent hydrocarbon groups, m is 10
Indicates a number of ~500. ) Polyoxyalkylene (B) whose molecular chain terminal is blocked with an epoxy group; General formula: H_2N-A-NH_2 (wherein A represents a substituted or unsubstituted divalent aromatic group) Represented aromatic diamine compound and (C) general formula; ▲Mathematical formula, chemical formula, table, etc.▼ (In the formula, R^3 and R^4 are divalent hydrocarbon groups, R^
5 represents a monovalent hydrocarbon group, R^6 represents an alkyl group having 1 to 6 carbon atoms, and a represents a number of 1 to 3. ) A general formula characterized by reacting an epoxy group represented by an organosilicon compound having a hydrolyzable group; ▲There are mathematical formulas, chemical formulas, tables, etc.▼ (In the formula, R^1, R^2 , R^3 and R^4 are divalent hydrocarbon groups, R^5 is a monovalent hydrocarbon group, R^6 is an alkyl group having 1 to 6 carbon atoms, and A is a substituted or unsubstituted divalent hydrocarbon group. aromatic group, a represents a number of 1 to 3, m represents a number of 10 to 500, n represents a number of 1 or more), and has a molecular weight of 5
00 to 50,000, a method for producing a polyether whose molecular chain ends are blocked with a hydrolyzable silyl group.