JPH04283258A - Curable composition - Google Patents

Abstract

PURPOSE:To prepare a curable compsn. which gives a cured article undergoing only a little increase in modulus due to a silane coupling agent by compounding an oxypropylene polymer having reactive silicon groups with the silane coupling agent. CONSTITUTION:An oxypropylene polymer having a main chain consisting of repeating units of formula I, silicon groups having hydroxyl or hydrolyzable groups directly attached to the silicon atoms [wherein R<1> and R<2> are each 1-20C alkyl, 6-20C aryl, 7-20C aralkyl, etc.; X is OH or a hydrolyzable group; and a is 0-3, b is 0-2, and m is 0-9 provided that a+SIGMAb>=1)], a ratio of Mw/Mn of 1.6 or lower, and a number-average mol.wt. of 6000 or higher is compound with a silane coupling agent (e.g. gamma-aminopropyltrimethoxysilane) to give a curable compsn., which gives a cured atricle undergoing only a little increase in modulus due to the silane coupling agent.

Description

[Detailed description of the invention]

0001

FIELD OF THE INVENTION This invention relates to a novel curable composition containing an oxypropylene polymer containing reactive silicon groups and a silane coupling agent.

0002

[Prior Art and Problems to be Solved by the Invention] Oxygen atoms containing a reactive silicon group (a silicon atom-containing group containing a silicon atom to which a hydroxyl group or a hydrolyzable group is bonded and capable of forming a siloxane bond) A propylene polymer can be a liquid polymer, and is cured at room temperature by moisture or the like to produce a rubber-like cured product. For this reason, it is used as an elastic sealant for buildings. When using this polymer, it is recommended to use it as a composition with a silane coupling agent in order to improve the storage stability of the polymer (prevent hardening during storage) and improve the adhesion of the cured product to the adherend. Sometimes used (JP-A-57-182350, JP-A-57-2054)
No. 43).

However, the cured product of such a composition has the disadvantage that the modulus, which is one of the tensile properties, is increased compared to the case where no silane coupling agent is added, and the properties as a rubber are impaired. There was found.

As a result of intensive studies, the present inventors have found that when an oxypropylene polymer with a narrow molecular weight distribution and a reactive silicon group is used, the increase in the modulus of the cured product is small even when a silane coupling agent is added. This discovery led to the present invention.

[0005]

[Means and effects for solving the problems] The curable composition of the present invention has (A) a polymeric main chain;

[0006]

[Case 2]

An oxypropylene polymer containing the repeating unit represented by: Oxypropylene whose Mn (weight average molecular weight/number average molecular weight) is 1.6 or less and whose number average molecular weight (Mn) is 6,000 or more.
(B) a silane coupling agent.

The reactive silicon group contained in the oxypropylene polymer as component (A) used in the present invention is not particularly limited, but typical ones include, for example, the following general formula: , a group represented by the formula 3 is exemplified.

[0009]

[Chemical formula 3]

[In the formula, R1 and R2 are both an alkyl group having 1 to 20 carbon atoms, an aryl group having 6 to 20 carbon atoms, an aralkyl group having 7 to 20 carbon atoms, or (R')3Si
It represents a triorganosiloxy group represented by O-, and when two or more R1 or R2 are present, they may be the same or different. Here, R' is carbon number 1
-20 monovalent hydrocarbon groups, and the three R's may be the same or different. X represents a hydroxyl group or a hydrolyzable group, and when two or more X's are present, they may be the same or different. a is 0
, 1, 2 or 3, and b represents 0, 1 or 2, respectively. Also, m

[0011]

[C4]

b in [0012] may be different. m is 0
Indicates an integer between ~19. However, it is assumed that a+Σb≧1 is satisfied. ] The hydrolyzable group represented by X above is not particularly limited, and may be any conventionally known hydrolyzable group. Specifically, examples thereof include a hydrogen atom, a halogen atom, an alkoxy group, an acyloxy group, a ketoximate group, an amino group, an amide group, an acid amide group, an aminooxy group, a mercapto group, and an alkenyloxy group. Among these, hydrogen atoms, alkoxy groups, acyloxy groups, ketoxymer
A to group, an amino group, an amide group, an aminooxy group, a mercapto group and an alkenyloxy group are preferable, and an alkoxy group such as a methoxy group is particularly preferable from the viewpoint of mild hydrolysis and easy handling.

One to three hydrolyzable groups or hydroxyl groups can be bonded to one silicon atom, and (a+Σb) is 1
It is preferable that it is 5. When two or more hydrolyzable groups or hydroxyl groups are present in the reactive silicon group, they may be the same or different.

[0014] The reactive silicon group may have one silicon atom, or two or more silicon atoms, but in the case of a reactive silicon group in which silicon atoms are linked by siloxane bonds, etc., there may be 20 silicon atoms. There may be some degree.

Note that a reactive silicon group represented by the following general formula, Chemical Formula 5, is preferred from the viewpoint of easy availability.

[0016]

[C5]

(In the formula, R2, cycloalkyl group such as, aryl group such as phenyl group, aralkyl group such as benzyl group, (R')3S where R' is a methyl group, phenyl group, etc.
Examples include a triorganosiloxy group represented by iO-. A methyl group is particularly preferred as R1, R2, and R'.

[0018] At least one reactive silicon group, preferably 1.1 to 5 reactive silicon groups, should be present in one molecule of the oxypropylene polymer. When the number of reactive silicon groups contained in one polymer molecule is less than one, curability becomes insufficient,
It becomes difficult to develop good rubber elastic behavior.

[0019] The reactive silicon group may be present at the end of the molecular chain of the oxypropylene polymer, or may be present internally. When a reactive silicon group is present at the end of the molecular chain, the effective network chain amount of the oxypropylene polymer component contained in the final cured product increases, resulting in high strength, high elongation, and low elastic modulus. It becomes easier to obtain a rubbery cured product.

The oxypropylene polymer constituting the polymer main chain in component (A) used in the present invention is:

002
1]

[C6]

It contains the repeating unit shown below. This oxypropylene polymer may be linear or branched, or a mixture thereof. In addition, other monomer units may be contained, but the monomer unit represented by chemical formula 6 is 5 in the polymer.
It is preferable that it is present in an amount of 0% by weight or more, preferably 80% by weight or more.

[0023] The number average molecular weight (Mn) of this oxypropylene polymer can be effectively used if it is 6,000 or more, but preferably one having a number average molecular weight of 6,000 to 30,000. Furthermore, this oxypropylene polymer has a ratio of weight average molecular weight to number average molecular weight (Mw/Mn) of 1.6 or less, and has an extremely narrow molecular weight distribution (high monodispersity). The value of Mw/Mn is preferably 1.5 or less, more preferably 1
．． 4 or less. Molecular weight distribution can be measured by various methods, but is usually measured by gel permeation chromatography (GPC).
Measurement using the method is common. Because the molecular weight distribution is narrow despite the large number average molecular weight, the composition of the present invention has a low viscosity and is easy to handle before curing, and exhibits good rubber-like elastic behavior after curing. .

The oxypropylene polymer having a reactive silicon group, which is component (A) of the present invention, is preferably obtained by introducing a reactive silicon group into an oxypropylene polymer having a functional group.

[0025] Oxypropylene polymers having high molecular weight, narrow molecular weight distribution, and functional groups can be obtained by a normal polymerization method for oxypropylene (anionic polymerization method using caustic alkali) or a chain extension reaction method using this polymer as a raw material. Although it is extremely difficult to do so, a special polymerization method called JP-A-61
-197631, JP 61-215622, JP 61-215623, JP 61-218632, JP 46-27250 and JP 59-1533
It can be obtained by the method described in No. 6 etc. Note that when a reactive silicon group is introduced, the molecular weight distribution tends to be broader than that of the polymer before introduction, so it is preferable that the molecular weight distribution of the polymer before introduction is as narrow as possible.

[0026] The reactive silicon group may be introduced by a known method. That is, for example, the following method may be mentioned.

(1) An oxypropylene polymer having a functional group such as a hydroxyl group at the end is reacted with an organic compound having an active group and an unsaturated group that is reactive with this functional group, and then the obtained The reaction product is hydrosilylated by acting on a hydrosilane having a hydrolyzable group.

(2) In the oxypropylene polymer having a functional group such as a hydroxyl group, an epoxy group, or an isocyanate group (hereinafter referred to as a Y functional group) at the end, a functional group that is reactive with the Y functional group is added. (hereinafter referred to as Y' functional group) and a compound having a reactive silicon group are reacted.

Examples of the silicon compound having the Y' functional group include γ-(2-aminoethyl)aminopropyltrimethoxysilane, γ-(2-aminoethyl)aminopropylmethyldimethoxysilane, and γ-aminopropyltriethoxysilane. Amino group-containing silanes such as γ-
Mercapto group-containing silanes such as mercaptopropyltrimethoxysilane, γ-mercaptopropylmethyldimethoxysilane, etc.; γ-glycidoxypropyltrimethoxysilane, β-(3,4-epoxycyclohexyl)ethyltrimethoxysilane, etc. Epoxysilanes; vinyl-type unsaturated group-containing silanes such as vinyltriethoxysilane, γ-methacryloyloxypropyltrimethoxysilane, γ-acryloyloxypropylmethyldimethoxysilane; γ-chloropropyltrimethoxysilane, etc. chlorine atom-containing silanes; γ
-Isocyanate-containing silanes such as isocyanatepropyltriethoxysilane and γ-isocyanatepropylmethyldimethoxysilane; specific examples include hydrosilanes such as methyldimethoxysilane, trimethoxysilane, methyldiethoxysilane, etc. However, it is not limited to these.

Among the above methods, method (1) or method (2) in which a polymer having a terminal hydroxyl group is reacted with a compound having an isocyanate group and a reactive silicon group is preferred.

The silane coupling agent which is component (B) of the present invention has a group containing a silicon atom to which a hydrolyzable group is bonded (hereinafter referred to as a hydrolyzable silicon group) and a functional group other than this group. It is a compound.

Examples of hydrolyzable silicon groups include those represented by formula 3 in which X is a hydrolyzable group. Examples of the hydrolyzable group include the groups already mentioned, but alkoxy groups such as methoxy group are preferred. The number of hydrolyzable groups is preferably 2 or more, particularly 3 or more.

Among the hydrolyzable silicon groups, groups represented by formula 5 are preferred. In particular, in chemical formula 5, a is 2 or 3
In the case of , especially the case of 3 is preferable.

Examples of functional groups other than the hydrolyzable silicon group include primary, secondary, and tertiary amino groups, mercapto groups, epoxy groups, carboxyl groups, vinyl groups, halogens, and isocyanate groups. Among these, amino groups, vinyl groups, etc. are preferred.

The hydrolyzable silicon group and other functional groups may be bonded to each other via a hydrocarbon group such as an alkylene group or an arylene group, but are not particularly limited thereto. The molecular weight of the silane coupling agent is 500 or less,
In particular, 300 or less is preferable.

Specific examples of silane coupling agents include:
γ-aminopropyltrimethoxysilane, γ-aminopropyltriethoxysilane, γ-aminopropylmethyldimethoxysilane, γ-(2-aminoethyl)aminopropyltrimethoxysilane, γ-(2-aminoethyl)
Aminopropylmethyldimethoxysilane, γ-(2-aminoethyl)aminopropyltrimethoxysilane, γ-
(2-aminoethyl)aminopropyltriethoxysilane, γ-ureidopropyltriethoxysilane, N-β
Amino group-containing silanes such as -(N-vinylbenzylaminoethyl)-γ-aminopropyltrimethoxysilane, γ-anilinopropyltrimethoxysilane; γ-mercaptopropyltrimethoxysilane, γ-mercaptopropyltriethoxysilane, Mercapto group-containing silanes such as γ-mercaptopropylmethyldimethoxysilane and γ-mercaptopropylmethyldiethoxysilane; γ
-Epoxy bond-containing silanes such as glycidoxypropyltrimethoxysilane, γ-glycidoxypropylmethyldimethoxysilane, γ-glycidoxypropyltriethoxysilane, and β-(3,4-epoxycyclohexyl)ethyltrimethoxysilane ; Carboxysilanes such as β-carboxyethyltriethoxysilane, β-carboxyethyl phenylbis(2-methoxyethoxy)silane, N-β-(N-carboxymethylaminoethyl)-γ-aminopropyltrimethoxysilane; Vinyl Vinyl-type unsaturated group-containing silanes such as trimethoxysilane, vinyltriethoxysilane, γ-methacryloyloxypropyltrimethoxysilane, γ-acryloyloxypropylmethyldimethoxysilane; such as γ-chloropropyltrimethoxysilane, etc. Chlorine atom-containing silanes; Examples include isocyanate-containing silanes such as γ-isocyanatepropyltriethoxysilane and γ-isocyanatepropylmethyldimethoxysilane. Further, modified derivatives thereof can also be used as silane coupling agents.

[0037] In the present invention, the silane coupling agent is
100 parts of reactive silicon group-containing oxypropylene polymer (
It is used in an amount of 0.01 to 20 parts by weight (hereinafter the same applies). In particular, it is preferably used in an amount of 0.1 to 10 parts. Only one type of silane coupling agent may be used, or two or more types may be used in combination.

Furthermore, when an amino group-substituted silane coupling agent is used as the component (B), a cured resin having particularly excellent adhesion properties to various adherends such as glass, stone, and metals as well as plastics and wood. A sexual composition is obtained.

As such an amino group-substituted silane coupling agent, an amino group-substituted alkoxysilane or an amino group-substituted alkoxysilane derivative compound is preferable. To give concrete examples of these,

[0040]

[C7]

[0041] The above amino group-substituted alkoxysilane and the above amino group-substituted alkoxysilane

[0042]

[Chemical formula 8]

A reaction product with an epoxysilane compound such as
Or with the above amino group-substituted alkoxysilane

[0044]

[Chemical formula 9]

Examples include reactants with methacryloxysilane compounds such as: The reaction between an amino group-substituted alkoxysilane and an epoxysilane compound or an acryloylsilane compound is carried out by mixing 0.2 to 5 moles of the silane compound with respect to 1 mole of the amino group-substituted alkoxysilane, and reacting the mixture at room temperature to 180°C. It can be easily obtained by stirring for ~8 hours.

[0046] In curing the composition of the present invention, a curing catalyst may or may not be used. When using a curing catalyst, a wide variety of conventionally known catalysts can be used. Specific examples include tetrabutyl titanate,
Titanate esters such as tetrapropyl titanate;
dibutyltin dilaurate, dibutyltin maleate,
Tin carboxylates such as dibutyltin diacetate, tin octylate, and tin naphthenate; reaction product of dibutyltin oxide and phthalate; dibutyltin diacetylacetonate; aluminum trisacetylacetonate, aluminum trisethyl acetoacetate, diisopropoxyaluminum ethyl Organoaluminum compounds such as acetoacetate; chelate compounds such as zirconium tetraacetylacetonate and titanium tetraacetylacetonate; lead octylate; butylamine, octylamine, laurylamine, dibutylamine, monoethanolamine, diethanolamine, triethanolamine , diethylenetriamine, triethylenetetramine, oleylamine, cyclohexylamine, benzylamine, diethylaminopropylamine,
Xylylenediamine, triethylenediamine, guanidine, diphenylguanidine, 2,4,6-tris(dimethylaminomethyl)phenol, morpholine, N-methylmorpholine, 2-ethyl-4-methylimidazole,
1,8-diazabicyclo(5.4.0) undecene-7
Amine compounds such as (DBU) or salts of these amine compounds with carboxylic acids; low molecular weight polyamide resins obtained from excess polyamines and polybasic acids; reaction products between excess polyamines and epoxy compounds; Examples include silanol condensation catalysts such as silanol condensation catalysts, and other known silanol condensation catalysts such as other acidic catalysts and basic catalysts. These catalysts may be used alone or in combination of two or more.

The amount of these curing catalysts used is 0.0 parts per 100 parts of the reactive silicon group-containing oxypropylene polymer.
About 1 to 20 parts is preferable, and about 1 to 10 parts is more preferable. If the amount of curing catalyst used is too small relative to the reactive silicon group-containing oxypropylene polymer, the curing rate may be slow and the curing reaction may be difficult to proceed sufficiently. On the other hand, if the amount of curing catalyst used is too large for the reactive silicon group-containing oxypropylene polymer, local heat generation and foaming will occur during curing, making it difficult to obtain a good cured product, which is not preferable.

The reactive silicon group-containing oxypropylene polymers can be modified by incorporating various fillers. Fillers include reinforcing fillers such as fume silica, precipitated silica, anhydrous silicic acid, hydrous silicic acid and carbon black; calcium carbonate, magnesium carbonate, diatomaceous earth, calcined clay, clay, talc, titanium oxide, bentonite, organic bentonite, ferric oxide, zinc oxide,
Examples include fillers such as activated zinc white, hydrogenated castor oil and shirasu balloons; fibrous fillers such as asbestos, glass fibers and filaments.

When it is desired to obtain a curable composition with high strength using these fillers, fume silica, precipitated silica,
1 to 100 parts of a filler selected from anhydrous silicic acid, hydrated silicic acid, carbon black, surface-treated fine calcium carbonate, calcined clay, clay, activated zinc white, etc., per 100 parts of the reactive silicon group-containing oxypropylene polymer. Favorable results can be obtained if used within the range of 50%. In addition, when it is desired to obtain a curable composition with low strength and high elongation, fillers mainly selected from titanium oxide, calcium carbonate, magnesium carbonate, talc, ferric oxide, zinc oxide, shirasu balloon, etc. Favorable results are obtained if the agent is used in an amount of 5 to 200 parts per 100 parts of the reactive silicon group-containing oxypropylene polymer. Of course, these fillers may be used alone or in a mixture of two or more.

In the curable composition of the present invention, it is more effective to use a plasticizer in combination with a filler, since the elongation of the cured product can be increased and a large amount of filler can be mixed. This plasticizer includes dioctyl phthalate,
Phthalate esters such as dibutyl phthalate, butylbenzyl phthalate; aliphatic dibasic acid esters such as dioctyl adipate, isodecyl succinate, dibutyl sebacate; glycol esters such as diethylene glycol dibenzoate, pentaerythritol ester; Aliphatic esters such as butyl oleate, methyl acetyl ricinolate, etc.; Phosphate esters such as tricresyl phosphate, trioctyl phosphate, octyldiphenyl phosphate, etc.; Epoxy plastics such as epoxidized soybean oil, benzyl epoxy stearate, etc. Agents: Polyester plasticizers such as polyesters of dibasic acid and dihydric alcohol; Polyethers such as polypropylene glycol and its derivatives; Polystyrenes such as poly-α-methylstyrene and polystyrene; Polybutadiene, butadiene-acrylonitrile Plasticizers such as copolymers, polychloroprene, polyisoprene, polybutene, and chlorinated paraffins can be used alone or in the form of a mixture of two or more types. The amount of plasticizer is 0 to 10 parts per 100 parts of the reactive silicon group-containing oxypropylene polymer.
Favorable results are obtained when used in the range of 0 parts.

The method for preparing the curable composition of the present invention is not particularly limited; for example, the above-mentioned components may be blended and kneaded using a mixer, roll, kneader, etc. at room temperature or under heating, or by adding a suitable solvent. Use a small amount to dissolve the ingredients,
Conventional methods such as mixing may be employed. Furthermore, by appropriately combining these components, one-pack type or two-pack type formulations can be created and used.

When the curable composition of the present invention is exposed to the atmosphere, it forms a three-dimensional network due to the action of moisture and hardens into a solid having rubber-like elasticity.

[0053] When using the curable composition of the present invention, if necessary, an adhesion improver, a physical property regulator,
Various additives such as anti-aging agents, ultraviolet absorbers, metal deactivators, anti-ozonants, light stabilizers, amine-based radical chain inhibitors, phosphorus-based peroxide decomposers, lubricants, pigments, foaming agents, etc. It can be added as appropriate.

The curable compositions of the present invention are particularly useful as elastic sealants and can be used as sealants for buildings, ships, automobiles, roads, and the like. Furthermore, it can be used alone or with the aid of a primer to adhere to a wide range of substrates such as glass, porcelain, wood, metal, resin moldings, etc., and thus can be used in various types of sealing and adhesive compositions. . Furthermore, it is useful as a food packaging material, a casting rubber material, a molding material, and a paint.

[0055]

Effects of the Invention The cured product of the composition of the present invention exhibits an increase in modulus due to the addition of component (B), compared to a cured product of a composition using a polymer with a wide molecular weight distribution as component (A). It has the effect of being small.

[0056] In the curable composition of the present invention, (A
The reactive silicon group-containing oxypropylene polymer used as component (2) has a narrow molecular weight distribution despite its large number average molecular weight. Therefore, before curing, the composition of the present invention has a lower viscosity and is easier to handle than a composition containing a conventional reactive silicon group-containing oxypropylene polymer having the same molecular weight and a wide molecular weight distribution.

[0057] Since the viscosity before curing is thus low, not only is workability good, but a large amount of filler can be blended and an excellent room temperature curable composition can be obtained.

Furthermore, chemical resistance such as acid resistance has been unexpectedly significantly improved, and solvent resistance and water resistance are also excellent.

[0059]

[Examples] In order to further clarify the present invention, Examples are given below.

Synthesis Example 1 A 1.5-liter pressure-resistant glass reaction vessel with a molecular weight of 15.0
00 polyoxypropylene triol (Mw/Mn=
1.38, viscosity 89 poise) was charged, and the mixture was placed under a nitrogen atmosphere.

At 137°C, add 19.1 g (0.099 g) of a 28% methanol solution of sodium methoxide from the dropping funnel.
(equivalent amount) was added dropwise, and after reacting for 5 hours, the mixture was devolatilized under reduced pressure. Returned to nitrogen atmosphere, allyl chloride 9.0g (0.118
After reacting for 1.5 hours, 5.6 g of a 28% methanol solution of sodium methoxide (0.
029 equivalents) and allyl chloride 2.7 g (0.035 equivalents)
Allylation was performed using

This reaction product was dissolved in hexane and adsorbed with aluminum silicate, and then the hexane was removed under reduced pressure to obtain 311 g of a yellow transparent polymer (viscosity 68 poise).

270 g (0.065 equivalent) of this polymer
was placed in a pressure-resistant glass reaction vessel and placed under a nitrogen atmosphere. Catalyst solution of chloroplatinic acid (H2PtCl6.6H2O
After adding 0.075 ml of a solution of 25 g dissolved in 500 g of isopropyl alcohol, the mixture was stirred for 30 minutes. 6.24 g (0.059 equivalent) of dimethoxymethylsilane was added from the dropping funnel, and after reacting at 90° C. for 4 hours, devolatilization was performed to obtain 260 g of a yellow transparent polymer.

Synthesis Example 2 Polyoxypropylene triol (Mw/Mn=1.38,
220 g (0.0447 equivalent) of viscosity 89 poise) and 0.02 g of dibutyltin dilaurate were charged, and 8.45 g (0.0447 equivalent) of γ-isocyanatepropylmethyldimethoxysilane was added dropwise at room temperature under a nitrogen atmosphere. After the dropwise addition was completed, the reaction was carried out at 75° C. for 1.5 hours. After measuring the IR spectrum and confirming the disappearance of NCO absorption near 2280 cm-1 and the generation of C=O absorption near 1730 cm-1, the reaction was terminated. 213 g of a colorless and transparent polymer was obtained.

Comparative Synthesis Example 1 420 g of polyoxypropylene glycol having a number average molecular weight of 3,000 and 80 g of polyoxypropylene triol having a number average molecular weight of 3,000 were charged into a pressure-resistant glass reaction vessel purged with nitrogen. Sodium hydroxide 40
g was added thereto and reacted at 60°C for 13 hours, and then 19g of bromochloromethane was reacted at 60°C for 10 hours. (Mw/Mn of the obtained polymer was 2.1, and the viscosity was 38
It was 5 poise. ) Subsequently, 15 g of allyl chloride was added and the reaction was carried out for 36 hours. After the reaction was completed, the pressure was reduced to remove volatile substances.

The contents were taken out into a beaker and dissolved in hexane. After adsorption treatment with aluminum silicate, hexane was removed under reduced pressure.

500 g of this polymer was charged into a reaction vessel purged with nitrogen, and a catalyst solution of chloroplatinic acid (H2PtCl
6.6H2O 25g to isopropyl alcohol 50g
After adding 0.03 g of the solution (dissolved in 0.0 g), 12 g of dimethoxymethylsilane was added and reacted at 80° C. for 4 hours. After the reaction was completed, volatile substances were removed under reduced pressure to obtain 550 g of a pale yellow transparent polymer.

The viscosity of the polymers obtained in Synthesis Examples 1 and 2 and Comparative Synthesis Example 1 was measured using a B-type viscometer (BM type rotor N).
o. 4, 12 rpm) at 23°C. In addition, the number average molecular weight (Mn) and molecular weight distribution (
Mw/Mn) was analyzed by GPC. GPC was analyzed using tetrahydrofuran as a distillation solvent in a column filled with polystyrene gel (manufactured by Tosoh Corporation) at an oven temperature of 40°C. The results are shown in Table 1.

[0069]

[Table 1]

Example 1 100 parts of the polymer obtained in Synthesis Example 1 as component (A), 3 parts of tin octylate and 0.5 part of laurylamine as curing catalyst, and N-β-(amino ethyl)
-After thoroughly mixing 5 parts of γ-aminopropyltrimethoxysilane, the mixture was carefully poured into a polyethylene mold to avoid air bubbles, and cured at 23°C for 2 days and then at 50°C for 3 days until the thickness was 3 mm. A cured product sheet was obtained.

From this cured material sheet, JISK6301
Punch out a size 3 dumbbell in accordance with
Tensile tests were performed at mm/min. As a result, the stress at 50% elongation was 3.16 kg/cm2.

Reference Example 1 100 parts of the polymer obtained in Synthesis Example 1, 3 parts of tin octylate, and 0.5 parts of laurylamine were thoroughly mixed, and a cured product sheet was prepared in the same manner as in Example 1. It was manufactured and subjected to a tensile test. As a result, the stress at 50% elongation was 3.07 kg/
It was cm2.

Comparative Example 1 100 parts of the polymer obtained in Comparative Synthesis Example 1, 3 parts of tin octylate, 0.5 parts of laurylamine, and 5 parts of N-β-(aminoethyl)-γ-aminopropyltrimethoxysilane. A cured product sheet was prepared in the same manner as in Example 1, and a tensile test was conducted. As a result, the stress at 50% elongation was 3.48 kg/cm2.

Reference Comparative Example 1 100 parts of the polymer obtained in Comparative Synthesis Example 1, 3 parts of tin octylate, and 0.5 part of laurylamine were thoroughly mixed, and the cured product was sealed in the same manner as in Example 1. A specimen was prepared and a tensile test was conducted. As a result, the stress at 50% elongation was 2.99k.
g/cm2.

As is clear from the stress at 50% elongation (50% modulus) of Comparative Example 1 and Reference Comparative Example 1, the value increases considerably by adding component (B). On the other hand, as is clear from the stress at 50% elongation in Example 1 and Reference Example 1, in the composition of the present invention, there is almost no increase in modulus even with the addition of component (B).

Example 2, Reference Example 2 A tensile test was conducted in the same manner as in Example 1 and Reference Example 1, using the polymer obtained in Synthesis Example 2 instead of the polymer obtained in Synthesis Example 1. Almost the same results as in Example 1 and Reference Example 1 were obtained.

Claims (5)

[Claims] [Claim 1] (A) An oxypropylene polymer whose main chain contains a repeating unit represented by [Formula 1] and at least one silicon atom-containing group containing a silicon atom to which a hydroxyl group or a hydrolyzable group is bonded. Coalescence, Mw/Mn is 1.6 or less and number average molecular weight is 6,000
A curable composition containing the above oxypropylene polymer and (B) a silane coupling agent. Claim 2: Mw/Mn of the polymer of component (A) is 1.5.
The curable composition according to claim 1, which is as follows. Claim 3: The number average molecular weight of the polymer of component (A) is 6,
The curable composition according to claim 1 or 2, which has a hardness of 000 to 30,000. 4. Any one of claims 1 to 3, wherein the silicon atom-containing group is present at the end of the molecular chain in the polymer of component (A).
The curable composition described in section. 5. The curable composition according to claim 1, wherein component (B) is an amino group-containing silane coupling agent.