JPH09176481A - Room temperature-curable composition - Google Patents

Abstract

PROBLEM TO BE SOLVED: To obtain a room temp.-curable compsn. being curable in the presence of moisture by using a polyoxyalkylene polymer contg. a specified hydrolyzable silicon group, a polyoxyalkylene polymer contg. no hydrolyzable silicon group and a specified hydroxyl group on its terminals and a curing catalyst. SOLUTION: This room temp.-curable compsn. consists of 100 pts.wt. polyoxyalkylene polymer (I) with a mol.wt. of 6,000-30,000 wherein at least 50% of whole terminal groups of the molecules are hydrolyzable silicon groups, 1-200 pts.wt. polyoxyalkylene polymer (II) contg. no hydrolyzable silicon group wherein at least 80% of the terminals are tertiary hydroxyl groups and/or hydroxyl groups with a structure of formula I (wherein R<1> is a 1-18C monovalent org. group) and 0.1-5 pts.wt. curing catalyst (III). The hydrolyzable silicon groups in the polyoxyalkylene polymer (I) are pref. a compd. of formula II (wherein R<2> is a 1-20C monovalent org. group and R<3> is a divalent org. group and X is a hydroxyl group or a hydrolyzable group and (a) is 1, 2 or 3).

Description

Detailed Description of the Invention

[0001]

TECHNICAL FIELD The present invention relates to a room temperature curable composition which cures in the presence of moisture.

[0002]

2. Description of the Related Art Polyoxyalkylene polymers having hydrolyzable silicon groups are liquid at room temperature, and since the cured products retain flexibility even at relatively low temperatures, they are widely used as sealing materials, adhesives, etc. Has been done.

As such a moisture-curable polymer,
A moisture-curable polyoxyalkylene polymer having a hydrolyzable silicon group at a terminal, which is described in JP-A-3-72527, JP-A-3-47825 and the like, can be mentioned.
In such a polyoxyalkylene polymer having a hydrolyzable silicon group at the terminal, generally, the larger the molecular weight, the more flexible the cured product is, but the higher the viscosity of the polymer is, and the workability is significantly deteriorated. Tend.

On the other hand, when the molecular weight of such a polymer is small, the viscosity is low but the cured product is inferior in flexibility. Until now, various plasticizers have been used in order to reduce the viscosity of the polymer while maintaining the flexibility of the cured product.

Examples of such plasticizers include aromatic carboxylic acid esters, aliphatic carboxylic acid esters, glycol esters, phosphoric acid esters, epoxy plasticizers,
Chlorinated paraffin is used. However, since these plasticizers have a migration property, when used in a sealing material or the like, they have a drawback that adverse effects such as contamination around the sealing portion and surface contamination after coating are exerted.

For the purpose of eliminating these drawbacks, the polyoxyalkylene polymer having a hydrolyzable silicon group is used as a plasticizer which does not lower the flexibility of the cured product and has a very low migration property. A curable composition containing a plasticizer has been proposed.

For example, in Japanese Patent Laid-Open No. 63-108058,
The main chain is a polyoxypropylene chain and has a hydroxyl group which is a propylene oxide residue at the end, for example, a molecular weight of 3
It has been proposed to use 000 high molecular weight polymers as plasticizers. However, when the present inventors have used this plasticizer in a system containing a polyoxyalkylene polymer having a hydrolyzable silicon group and a curing catalyst, a significant increase in viscosity and a decrease in curability in a storage stability test are observed. Was found to occur.

On the other hand, Japanese Patent Application Laid-Open No. 1-279958 proposes, as a polymer plasticizer, polyoxypropylene in which hydroxyl groups of polyoxypropylene polyol are capped with alkyl ether and essentially free of hydroxyl groups.
However, in order to seal the hydroxyl end of polyoxypropylene polyol with an alkyl ether, it is usually accompanied by the process of alkyl etherification of the end hydroxyl group accompanied by desalting purification, and compared with a system using an inexpensive low molecular weight plasticizer. Then, there was a difficulty that the cost increased significantly.

[0009]

DISCLOSURE OF THE INVENTION The present inventors have found that the polyoxyalkylene polymer having a function as a plasticizer and having a hydrolyzable silicon group hardly influences the curability and the storage stability of the polyoxyalkylene polymer. In order to find a polymer plasticizer which can be produced at low cost, the present invention has been accomplished by carefully studying the effect of the terminal structure of the polymer plasticizer on the polyoxyalkylene polymer having a hydrolyzable silicon group.

[0010]

That is, the present invention is the following inventions. 100 parts by weight of a polyoxyalkylene polymer (I) having a molecular weight of 6000 to 30,000 in which the main chain is essentially made of polyoxyalkylene and 50% or more of all molecular end groups are hydrolyzable silicon groups, and the main chain is essentially Polyoxyalkylene polymers (II) 1 to 200 consisting of polyoxyalkylene and containing no hydrolyzable silicon group
In a curable composition containing 0.1 to 5 parts by weight of a curing catalyst (III) of polyoxyalkylene polymer (I), a polyoxyalkylene polymer (II)
80% or more of the terminal of the above is a tertiary hydroxyl group and / or a hydroxyl group-containing group having a structure represented by the formula (1), and the room temperature curable composition is characterized.

A polyoxyalkylene polymer whose main chain consists essentially of polyoxyalkylene and does not contain hydrolyzable silicon groups, in which 80% or more of the terminals are tertiary hydroxyl groups and / or are represented by the formula (1). Having a structure represented by a hydroxyl group-containing group, a polyoxyalkylene polymer (II)
A composition containing as a plasticizer.

--OCH (OH) CH ₂ R ¹ (1) In the formula (1), R ¹ represents a substituted or unsubstituted monovalent organic group having 1 to 18 carbon atoms.

[0013]

BEST MODE FOR CARRYING OUT THE INVENTION The present invention relates to a polyoxyalkylene polymer (I) and a polyoxyalkylene polymer (I) each of which has a main chain consisting essentially of polyoxyalkylene.
I) and a curing catalyst (III) for the polyoxyalkylene polymer (I).

The polyoxyalkylene polymer (I) is preferably one obtained by introducing a hydrolyzable silicon group into a hydroxyl group-containing polyoxyalkylene polymer by a suitable method.

Such a polymer is disclosed, for example, in JP-A-3-
47825, JP-A-3-72527, JP-A-3-796
27, JP-B-46-30711, JP-B-45-3631
9, proposed in Japanese Examined Patent Publication No. 46-17553.

The hydroxyl group-containing polyoxyalkylene polymer used as a raw material is preferably one obtained by polymerizing a monoepoxide such as alkylene oxide in the presence of an initiator and a catalyst.

As the initiator, compounds having 2 to 10 active hydrogens are preferable. A polyhydroxy compound is preferable, and a polyhydroxy compound having 2 to 8, especially 2 to 3 hydroxyl groups is preferable.

Specifically, ethylene glycol, diethylene glycol, propylene glycol, dipropylene glycol, neopentyl glycol, 1,4-butanediol, 1,6-hexanediol, glycerin, trimethylolpropane, pentaerythritol, diglycerin, choux. There are clauses and polyols having a lower molecular weight than the target product obtained by reacting these with monoepoxide. These may be used alone or in combination of two or more. Further, an unsaturated group-containing monohydroxy compound such as allyl alcohol can also be used.

Examples of monoepoxides include propylene oxide, 1,2-butylene oxide, 2,3-butylene oxide, ethylene oxide and allyl glycidyl ether. Propylene oxide is particularly preferred.

Examples of the catalyst include alkali metal catalysts, complex metal cyanide complex catalysts and metal porphyrin catalysts.

Particularly preferred hydroxyl group-containing polyoxyalkylene polymers are polyoxypropylene diol, polyoxypropylene triol, polyoxypropylene tetraol and polyoxypropylene hexaol. When used in the methods (a) and (d) below, olefin-terminated polyoxyalkylene such as polyoxypropylene glycol monoallyl ether can also be used.

The hydrolyzable silicon group may be any silicon group that undergoes hydrolysis and crosslinking reaction in moisture. Silicon-containing groups having hydrolyzable groups directly bonded to silicon atoms can be used. For example, the group represented by the formula (2) is preferable.

--R ³ --SiX _a R ² _3-a (2) In the formula (2), R ² is a substituted or unsubstituted monovalent organic group having 1 to 20 carbon atoms, R ³ is a divalent organic group, X is a hydroxyl group or a hydrolyzable group, a is 1,
2 or 3.

As R ² in the formula (2), an alkyl group having 8 or less carbon atoms, a phenyl group or a fluoroalkyl group is preferable, and a methyl group or an ethyl group is particularly preferable.

X is a hydroxyl group or a hydrolyzable group, and examples of the hydrolyzable group include a halogen atom, an alkoxy group, an acyloxy group, an amide group, an amino group, an aminooxy group, a ketoximate group and a hydride group. Of these, the hydrolyzable group having a carbon atom preferably has 6 or less carbon atoms, and particularly preferably 4 or less carbon atoms. Examples of preferable X include a lower alkoxy group having 4 or less carbon atoms, particularly a methoxy group, an ethoxy group and a propoxy group. A methoxy group is particularly preferable. a is preferably 2 or 3.

Next, the polyoxyalkylene polymer (I)
The method of introducing the hydrolyzable silicon group in 1 will be described. For example, a hydrolyzable silicon group is introduced into the terminal of the hydroxyl group-containing polyoxyalkylene polymer by the following methods (a) to (d).

(A) A method of reacting a hydroxyl group-containing polyoxyalkylene polymer having an unsaturated group introduced therein with a silicon hydride compound represented by the formula (3) in the presence of a catalyst.

HSiX _a R ² _3-a (3) However, in the formula (3), R ² , X and a are the same as described above.

Here, as a method for obtaining a hydroxyl group-containing polyoxyalkylene polymer having an unsaturated group introduced therein, OH which is a terminal hydroxyl group of the hydroxyl group-containing polyoxyalkylene polymer is OM (M is an alkali metal). And then
A method of reacting with an unsaturated group-containing halogenated hydrocarbon such as allyl chloride, or a method of reacting a compound having an unsaturated group and a hydroxyl group-reactive functional group with a hydroxyl group, and binding with an ester bond, a urethane bond, a carbonate bond, etc. is there.

Further, when the monoepoxide is polymerized in the production of the hydroxyl group-containing polyoxyalkylene polymer, the unsaturated group is introduced into the side chain by copolymerizing the unsaturated group-containing monoepoxide such as allyl glycidyl ether. It can also be obtained by using a terminally unsaturated group-containing monohydroxy compound as a method or an initiator.

(B) A method of reacting a compound having an isocyanate group and a hydrolyzable silicon group with a hydroxyl group-containing polyoxyalkylene polymer.

(C) After a hydroxyl group-containing polyoxyalkylene polymer and a polyisocyanate compound such as tolylene diisocyanate are reacted to form an isocyanate group terminal, W of the silicon compound represented by the formula (4) is added to the isocyanate group. Method of reacting groups.

R ² _3-a -SiX _a -R ⁴ W (4) However, in the formula (4), R ² , X and a are the same as described above, and R ⁴ is a divalent organic group. And W is a hydroxyl group, a carboxyl group, a mercapto group and an amino group (primary or secondary
It is an active hydrogen-containing group selected from the group).

(D) A method of reacting an unsaturated group obtained by introducing an unsaturated group into a hydroxyl group-containing polyoxyalkylene polymer with a mercapto group of a silicon compound represented by the formula (4) in which W is a mercapto group. .

The number of hydrolyzable silicon groups in the polyoxyalkylene polymer (I) of the present invention is 50% of all molecular terminal groups.
It is 100% or less and 60% or more and 100% or less. The number of molecular terminal groups per molecule is preferably 2-8, and particularly preferably 2-3.

As the polyoxyalkylene polymer (I) of the present invention, a polymer having a molecular weight of 6000 to 30,000 is used. When the molecular weight of the polymer (I) is lower than 6000, in order to make the cured product flexible, the proportion of hydrolyzable silicon groups in all the molecular end groups is decreased as compared with that of a higher molecular weight. It has to be hardened and the curability deteriorates. When the molecular weight exceeds 30,000, the workability is remarkably deteriorated due to high viscosity even after mixing with the polyoxyalkylene polymer (II). Preferred molecular weight is 1000
0 to 20,000.

The polyoxyalkylene polymer (II) whose main chain consists essentially of polyoxyalkylene and does not contain a hydrolyzable silicon group has a tertiary hydroxyl group and / or a structure represented by the above formula (1). It is a hydroxyl group-containing group.

R ¹ is a substituted or unsubstituted monovalent organic group having 1 to 18 carbon atoms, preferably a hydrocarbon group, and particularly preferably a hydrocarbon group having 1 to 12 carbon atoms.

Polyoxyalkylene polymer (II)
Is obtained by polymerizing a monoepoxide capable of forming a tertiary hydroxyl group terminal or a hydroxyl group-containing group terminal having a structure represented by the formula (1) in the presence of an initiator and a catalyst.

The polyoxyalkylene constituting the main chain can be freely selected, and a suitable monoepoxide is polymerized in the presence of an initiator and a catalyst to obtain a hydroxyl group-containing polyoxyalkylene polymer and It can also be obtained by converting the structure into a hydroxyl group-containing group having a tertiary hydroxyl group and / or a structure represented by the formula (1).

The latter method is particularly preferred in the present invention. That is, a monoepoxide capable of forming a tertiary hydroxyl group terminal or a hydroxyl group-containing group terminal having a structure represented by the formula (1) usually has low reactivity and takes a long time to polymerize, and the viscosity of a polymer to be generated. Is relatively high, a polyoxyalkylene polymer having a molecular weight close to a predetermined molecular weight obtained in advance from a highly reactive monoepoxide such as ethylene oxide or propylene oxide is obtained. Alternatively, a method of treating with a monoepoxide capable of forming a hydroxyl group-containing group terminal having a structure represented by the formula (1) is preferable as a production method.

In this case, the tertiary hydroxyl group end or the formula (1)
Such a monoepoxide capable of forming a hydroxyl group-containing group terminal having a structure of 0.8 to 10 times the mole number of the hydroxyl group terminal of the polyoxyalkylene polymer forming the main chain,
Particularly preferably, 1 to 5 times the molar amount may be reacted. When using the above catalyst, depending on the type of monoepoxide,
80% or more of the terminal hydroxyl groups are converted into tertiary hydroxyl groups or hydroxyl group-containing group terminals having the structure of formula (1), and can be used as the polymer plasticizer of the present invention.

Examples of monoepoxides forming a tertiary hydroxyl group end include isobutylene oxide, 2-methyl-1,2.
-Pentene oxide, 1-methyl-1,2-cyclohexene oxide, etc., and 1,2-butylene oxide, 1,2-butylene oxide, 1,2 as a monoepoxide forming a hydroxyl group-containing group terminal having a structure represented by the formula (1). Examples include terminal monoepoxides such as pentene oxide and 1,2-decene oxide, and glycidyl ethers such as cyclohexene oxide, methyl glycidyl ether, allyl glycidyl ether, and phenyl glycidyl ether.

Particularly preferred polyoxyalkylene polymer (II) is polyoxypropylene diol,
It is obtained by copolymerizing polyoxypropylene triol, polyoxypropylene tetraol and polyoxypropylene hexaol with isobutylene oxide. Further, a polyoxypropylene monool obtained by polymerizing propylene oxide with a monool such as butanol as an initiator and a hydroxyl group end thereof similarly converted to a tertiary hydroxyl group end is particularly preferable.

The molecular weight of the polyoxyalkylene polymer (II) of the present invention is 1,000 to 30,000, especially 3
000 to 10,000 are preferable from the viewpoint of viscosity and migration prevention.

In the present invention, 1 to 200 parts by weight of the polyoxyalkylene polymer (II) is used with respect to 100 parts by weight of the polyoxyalkylene polymer (I). The polyoxyalkylene polymer (II) is preferably 10 to 150.
Parts by weight, particularly preferably 20 to 100 parts by weight, are used.

The room temperature curable composition in the present invention is based on 100 parts by weight of the polyoxyalkylene polymer (I).
It can be produced by mixing 1 to 200 parts by weight of the polyoxyalkylene polymer (II).

Further, in the composition of the present invention, 0.1 to 5 parts by weight of the curing catalyst (III) of the polyoxyalkylene polymer (I) is essential for 100 parts by weight of the polyoxyalkylene polymer (I). Used as an ingredient. The composition of the present invention is characterized by being particularly excellent in storage stability in the presence of this curing catalyst, particularly in curing stability.

The following compounds can be used as the curing catalyst.

Metal titanates, organosilicon titanates, metal salts such as bismuth tris-2-ethylhexoate, acidic compounds such as phosphoric acid, p-toluenesulfonic acid and phthalic acid, butylamine, hexylamine, octyl Amine, decylamine, aliphatic monoamines such as laurylamine, ethylenediamine, aliphatic diamines such as hexanediamine, diethylenetriamine, triethylenetetramine, aliphatic polyamines such as tetraethylenepentamine, piperidine, heterocyclic amines such as piperazine, Amine compounds such as aromatic amines such as metaphenylenediamine, ethanolamines, triethylamine, and various modified amines used as a curing agent for epoxy resins.

Mixtures of the above amines with divalent tin such as tin dioctylate, tin dinaphthenate and tin distearate.

Dibutyltin diacetate, dibutyltin dilaurate, dioctyltin dilaurate and the following carboxylic acid type organotin compounds and mixtures of these carboxylic acid type organotin compounds with the above amines. (nC ₄ H ₉ ) ₂ Sn (OC
OCH = CHCOOCH ₃ ) ₂ , (nC ₄ H ₉ ) ₂ Sn (OCOCH = CHCOOC ₄ H ₉ -n) ₂ ,
(nC ₈ H ₁₇ ) ₂ Sn (OCOCH = CHCOOCH ₃ ) ₂ , (nC ₈ H ₁₇ ) ₂ Sn (OCOCH
= CHCOOC ₄ H ₉ -n) ₂ , (nC ₈ H ₁₇ ) ₂ Sn (OCOCH = CHCOOC ₈ H ₁₇ -iso)
₂ .

The following sulfur-containing organotin compounds: (nC ₄ H ₉ ) ₂ S
n (SCH ₂ COO), (nC ₈ H ₁₇ ) ₂ Sn (SCH ₂ COO), (nC ₈ H ₁₇ ) ₂ Sn (S
CH ₂ CH ₂ COO), (nC ₈ H ₁₇ ) ₂ Sn (SCH ₂ COOCH ₂ CH ₂ OCOCH ₂ S), (n
-C ₄ H ₉ ) ₂ Sn (SCH ₂ COOC ₈ H ₁₇ -iso) ₂ , (nC ₈ H ₁₇ ) ₂ Sn (SCH ₂ COO
C ₈ H ₁₇ -iso) ₂ , (nC ₈ H ₁₇ ) ₂ Sn (SCH ₂ COOC ₈ H ₁₇ -n) ₂ , (nC
₄ H ₉ ) ₂ SnS.

Organotin oxides such as (nC ₄ H ₉ ) ₂ SnO and (nC ₈ H ₁₇ ) ₂ SnO, and these organotin oxides and ethyl silicates, dimethyl maleate, diethyl maleate, dioctyl maleate and phthalic acid. Reaction products with ester compounds such as dimethyl, diethyl phthalate and dioctyl phthalate.

The following chelate tin compounds and reaction products of these tin compounds with alkoxysilanes (provided that
acac is an acetylacetonate ligand). (nC ₄ H ₉ ) ₂ Sn
(acac) ₂ , (nC ₈ H ₁₇ ) ₂ Sn (acac) ₂ , (nC ₄ H ₉ ) ₂ (C ₈ H ₁₇ O) S
n (acac).

The following tin compounds. (nC ₄ H ₉ ) ₂ (CH ₃ COO) SnOSn
(OCOCH ₃ ) (nC ₄ H ₉ ) ₂ , (nC ₄ H ₉ ) ₂ (CH ₃ O) SnOSn (OCH ₃ ) (nC
₄ H ₉ ) ₂ .

The composition of the present invention may contain various known fillers, additives and, if necessary, solvents and the like.

As the filler, for example, the following known fillers can be used. Calcium carbonate whose surface is surface-treated with a fatty acid or a resin acid organic compound, and further finely powdered, colloidal calcium carbonate having an average particle size of 1 μm or less, light calcium carbonate having an average particle size of 1 to 3 μm produced by a precipitation method, average particles Calcium carbonate such as ground calcium carbonate having a diameter of 1 to 20 μm, fumed silica, precipitated silica, silicic acid anhydride, hydrous silicic acid and carbon black, magnesium carbonate, diatomaceous earth, calcined clay, clay, talc, titanium oxide, bentonite, Powdered fillers such as organic bentonite, ferric oxide, zinc oxide, activated zinc oxide, shirasu balloon, wood flour, pulp, cotton chips, mica, walnut flour, rice flour, graphite, fine aluminum powder, and flint powder. Asbestos, glass fiber, glass filament,
Fibrous fillers such as carbon fiber, Kevlar fiber and polyethylene fiber.

The amount of the filler used is the polyoxyalkylene polymer (I) and the polyoxyalkylene polymer (II).
1 to 1000% by weight, especially 50 to 250
% By weight is preferred. Even if these fillers are used alone,
Two or more kinds may be used in combination.

The room-temperature-curable composition of the present invention has a sufficiently low viscosity by itself, and it is preferable that essentially no plasticizer is used, but a plasticizer may be used.

Examples of the plasticizer include dioctyl phthalate, dibutyl phthalate, butylbenzyl phthalate, and other phthalic acid alkyl esters, dioctyl adipate,
Diisodecyl succinate, dibutyl sebacate, alkyl carboxylic acid esters such as butyl oleate, glycol esters such as pentaerythritol ester, trioctyl phosphate, phosphates such as tricresyl phosphate, epoxidized soybean oil, Epoxy plasticizers such as benzyl epoxy stearate and chlorinated paraffins can be used alone or in a mixture of two or more kinds.

However, among such plasticizers, the low molecular weight plasticizer has a problem that it tends to bleed out after curing the room temperature curable composition of the present invention, and has an influence on the curability storage stability. Not preferably. That is, it is preferable that the room temperature curable composition of the present invention further contains a plasticizer, and the plasticizer is not a low molecular weight plasticizer. The low molecular weight plasticizer refers to a plasticizer in which the compound itself has a low molecular weight and does not have a reactive group. For example, phthalic acid alkyl esters.

A hydrolyzable silicon compound may be optionally added to the composition of the present invention for the purpose of controlling the physical properties and curability of the cured product. Specific examples of such a compound include tetramethyl silicate, vinyltrimethoxysilane,
Examples thereof include, but are not limited to, methyltrimethoxysilane, dimethyldimethoxysilane, trimethylmethoxysilane, and compounds in which these methoxy groups are substituted with ethoxy groups.

Further, an adhesiveness-imparting agent may be used for the purpose of improving the adhesiveness. Examples of these adhesiveness-imparting agents include the following.

(Meth) acrylsilanes such as γ-methacryloxypropyltrimethoxysilane, γ-acryloxypropyltrimethoxysilane and γ-methacryloxypropylmethyldimethoxysilane.

Γ-aminopropyltrimethoxysilane,
γ-aminopropyltriethoxysilane, γ-aminopropylmethyldimethoxysilane, N-β- (aminoethyl) -γ-aminopropyltrimethoxysilane, N-β
-(Aminoethyl) -γ-aminopropylmethyldimethoxysilane, N-β- (aminoethyl) -γ-aminopropyltriethoxysilane, γ-ureidopropyltriethoxysilane, N-β- (N-vinylbenzylaminoethyl) ) -Γ-Aminopropyltrimethoxysilane, γ
-Amino group-containing silanes such as anilinopropyltrimethoxysilane.

Γ-Mercaptopropyltrimethoxysilane, γ-mercaptopropyltriethoxysilane, γ-
Mercaptosilanes such as mercaptopropylmethyldimethoxysilane and γ-mercaptopropylmethyldiethoxysilane.

Epoxysilanes such as γ-glycidoxypropyltrimethoxysilane, γ-glycidoxypropylmethyldimethoxysilane, γ-glycodoxypropyltriethoxysilane, β-carboxyethyltriethoxysilane, β-carboxyethyl Carboxysilanes such as phenylbis (2-methoxyethoxy) silane and N-β- (N-carboxylmethylaminoethyl) -γ-aminopropyltrimethoxysilane.

These silane coupling agents may be used alone or in combination of two or more kinds. Moreover, you may use the addition reaction product of 2 or more types of silane coupling agents. Examples of such adducts include a reaction product of an amino group-containing silane compound and an epoxysilane compound, a reaction product of an amino group-containing silane compound and a (meth) acrylsilane compound, a reaction product of an epoxysilane compound and a mercaptosilane compound, and mercaptosilane. Examples thereof include reaction products of compounds, and these reaction products are easily obtained by mixing the silane compound and stirring the mixture at room temperature to 150 ° C. for 1 to 8 hours.

Further, other additives include thixotropic agents, modifiers such as phenol resins and epoxy resins, pigments, various stabilizers, and photo-curing agents for surface modification such as oligoester acrylates. A compound etc. are mentioned. Also, a solvent may be used for the purpose of adjusting the viscosity.

The room temperature curable composition of the present invention can be used as a sealing material, particularly as an elastic sealing material or an adhesive.

The polyoxyalkylene polymer (II) in the present invention is the polyoxyalkylene polymer (I).
It is believed to act as a plasticizer when mixed with.
However, it is not limited to the polyoxyalkylene polymer (I) and can be used as a plasticizer for polymers other than the polymer (I).

The present invention is also a polyoxyalkylene polymer whose main chain consists essentially of polyoxyalkylene and does not contain hydrolyzable silicon groups, wherein 80% or more of the terminals have tertiary hydroxyl groups and / or formula ( The polyoxyalkylene polymer (I, which is a hydroxyl group-containing group having the structure of 1)
A composition containing I) as a plasticizer.

[0074]

EXAMPLES The present invention will be described in more detail with reference to Synthesis Examples, Examples and Comparative Examples, but the present invention is not limited to these. Synthesis Examples 1 to 3 are polyoxyalkylene polymer (I), and Synthesis Examples 4 to 8 are polyoxyalkylene polymer (II).

[Synthesis Example 1: Polymer a] The terminal hydroxyl group of polyoxypropylene diol obtained by reacting propylene oxide with ethylene glycol as an initiator in the presence of a zinc hexacyanocobaltate complex catalyst was converted to an allyloxy group. After purification. Further, chloroplatinic acid was used as a catalyst to react with methyldimethoxysilane to synthesize a polymer a having a molecular weight of about 17,000 in which a methyldimethoxysilylpropyl group was introduced into 75% of all molecular terminal groups. The viscosity at 25 ° C. was 15000 cP.

[Synthesis Example 2: Polymer b] A molecular weight of about 1 obtained by reacting propylene oxide with glycerin as an initiator in the presence of a zinc hexacyanocobaltate complex catalyst.
After converting the terminal hydroxyl group of 7000 polyoxypropylene triol to an allyloxy group, it was purified. Furthermore, a polymer b was synthesized by reacting with methyldimethoxysilane using chloroplatinic acid as a catalyst to introduce a methyldimethoxysilylpropyl group into 65% of all molecular terminal groups. The viscosity at 25 ° C. was 9500 cP.

[Synthesis Example 3: Polymer c] In the same manner as in Synthesis Example 2, a polymer c was synthesized in which a methyldimethoxysilylpropyl group was introduced into 91% of all molecular terminal groups. The viscosity at 25 ° C. was 8800 cP.

[Synthesis Example 4: Monool D] Using butanol as an initiator, propylene oxide was reacted at 110 ° C. in the presence of a zinc hexacyanocobaltate complex catalyst to obtain polyoxypropylene monool having a molecular weight of about 4900. Further, 2.1 times mol of isobutylene oxide was added to all the hydroxyl groups at the same temperature at the same temperature for reaction to convert the terminal hydroxyl groups to tertiary hydroxyl groups, and the molecular weight was about 500.
0 of polyoxypropylene monool D was obtained. H-N
From MR, it was confirmed that the proportion of tertiary hydroxyl groups in this product was 94% of all hydroxyl terminal groups. The viscosity of this product at 25 ° C. was 4800 cP.

[Synthesis Example 5: Diol E] Using ethylene glycol as an initiator, propylene oxide was reacted at 110 ° C. in the presence of a zinc hexacyanocobaltate complex catalyst to obtain a polyoxypropylene triol having a molecular weight of about 7800. Further, 2.2 times mol of isobutylene oxide was added to all the hydroxyl group terminals at the same temperature and reacted to obtain polyoxypropylene diol E having a molecular weight of about 8000 in which 89% of the terminal hydroxyl groups were converted to tertiary hydroxyl groups. It was The viscosity of this product at 25 ° C. was 5200 cP.

[Synthesis Example 6: Triol F] Using pentaerythritol as an initiator, propylene oxide was reacted at 110 ° C. in the presence of a zinc hexacyanocobaltate complex catalyst to obtain polyoxypropylene tetraol having a molecular weight of about 7,400. Furthermore, after adding potassium hydroxide to this product, 3.5-fold molar amount of 1,2-
Decene oxide was added at the same temperature to obtain 98
% Was obtained _{-CH (OH) (CH 2)} 8 CH 3 with a secondary hydroxyl group is converted to molecular weight of about 8000 represented polyoxypropylene triol F. The viscosity of this product at 25 ° C. was 5700 cP.

[Synthesis Example 7: Tetraol G] Polyoxypropylenetriol having a molecular weight of about 2900 was obtained using glycerin as an initiator in the presence of a potassium hydroxide catalyst. Further, a 3-fold molar amount of phenyl glycidyl ether was added to all the hydroxyl groups at 120 ° C., and 96% of the terminal hydroxyl groups became secondary hydroxyl groups represented by —CH (OH) CH ₂ —O—C ₆ H _5. A converted polyoxypropylene tetraol G having a molecular weight of about 3500 was obtained. 25 ℃ of this thing
The viscosity at was 2700 cP.

[Examples 1 to 6 and Comparative Examples 1 to 5] Table 1
100 parts by weight (hereinafter referred to as “part”) of the polyoxyalkylene polymer (I) synthesized in Synthesis Examples 1 to 3, the polyoxyalkylene polymer (II) synthesized in Synthesis Examples 4 to 7, or To 60 parts of the plasticizer used in the comparative example, 75 parts of calcium carbonate (made by Shiraishi Calcium, white luster CCR)
Part, calcium carbonate (Shiraishi calcium, Whiten S
B) 75 parts, titanium dioxide 20 parts, stabilizer (mixture of antioxidant, UV absorber, light stabilizer, Ciba Geigy, Tinuvin B75) 2 parts, vinyltrimethoxysilane (Shin-Etsu Chemical Co., Ltd., KBM1003) 3 parts , Amine-based silane coupling agent (KBM603, manufactured by Shin-Etsu Chemical Co., Ltd.)
3 parts, 1 part of Disparon 6500 (Kusumoto Kasei, fatty acid amide thixotropic agent) and 2 parts of dibutyltin bisacetylacetonate (Nitto Kasei Kogyo, U220) were added and kneaded under the condition that moisture was not mixed, A homogeneous mixed composition was obtained.

20% of this composition was used in a state in which moisture was shut off.
After left at 3 ° C. for 3 days, the following tests, that is, changes in composition viscosity, curability, physical properties of the cured product, and surface transferability of the plasticizer, were performed to determine initial physical properties. Table 1 shows the results.
It is shown in FIG.

Further, as a storage stability test, the same mixed composition was stored at 50 ° C. for 30 days in a state where moisture was blocked, and tests were conducted on items other than surface migration of the plasticizer to compare with initial physical properties. The results are shown in Tables 1 and 2.

The plasticizers H to L are as follows. H: butanol initiated polyoxypropylene monool (molecular weight 5000), I: ethylene glycol initiated polypropylene diol (molecular weight 8000), J: pentaerythritol initiated polypropylene tetraol (molecular weight 8000), K: glycerine initiated polypropylene triol (molecular weight 4000), L: di (2-ethylhexyl) phthalate.

(1) Composition viscosity change: B8U type viscometer 2
The viscosity at 0 ° C. was measured. The evaluation was indicated by ◯: the viscosity after the storage stability test was less than 1.5 times the initial viscosity, and x: more than that.

(2) Curability: Mixture at 20 ° C., 65% R
The curability after standing for 5 hours under the condition of H was evaluated by touch with a finger.
In the evaluation, ◯ means that it is tack-free, and × means that it is not tack-free.

(3) Physical properties of cured product: JIS from the above composition
Create an H-type test piece based on A5758, 20 ℃, 7
After further curing and curing at 30 ° C. for 7 days, 50% modulus M ₅₀ (unit: kg / cm ² ), breaking strength (unit: kg / cm ² ) and breaking elongation (unit:
%) Was evaluated.

(4) Surface migration of plasticizer: The surface of an unpainted cured product was allowed to stand at 50 ° C. for 1 week and then tested for bleed-out of unreacted substances on the surface by touching with a finger. ○: Bleed-out Was not observed, x: Bleed out was observed.

As can be seen from the table, when the polyoxyalkylene polymer (II) of the present study is used as the polymer plasticizer, the surface migration of the plasticizer does not occur. Further, the initial curability and the physical properties of the cured product are excellent, the degree of thickening of the composition after the storage stability test is small, and the curability and the physical properties of the cured product are not significantly affected.

On the other hand, as shown in Comparative Examples 1 to 4, when a polymer plasticizer other than the present invention was used, the initial physical properties and surface migration were excellent, but the thickening and curability after the storage stability test were excellent. It was found that the deterioration of the material and the deterioration of the physical properties were remarkable. Further, in Comparative Example 5 using a low molecular weight plasticizer, it was found that the plasticizer has a large surface migration property and also has poor storage stability.

[0092]

[Table 1]

[0093]

[Table 2]

[0094]

The room temperature curable composition of the present invention provides a cured product having excellent workability, flexibility as an elastic material and excellent stain resistance. Further, it provides a composition having excellent storage stability and having almost no deterioration in curability and workability due to long-term storage.

Front page continued (72) Inventor Tatsuo Onoguchi 1150, Hazawa-machi, Kanagawa-ku, Yokohama, Kanagawa Prefecture Asahi Glass Co., Ltd. Central Research Laboratory (72) Inventor Takao Doi, 1150, Hazawa-machi, Kanagawa-ku Yokohama City, Kanagawa Prefecture Asahi Glass Co., Ltd. Central Research Center

Claims (4)

[Claims] 1. A polyoxyalkylene polymer (I) having a molecular weight of 6000 to 30000, wherein the main chain consists essentially of polyoxyalkylene and 50% or more of all molecular terminal groups are hydrolyzable silicon groups, 1 to 200 parts by weight of a polyoxyalkylene polymer (II) whose main chain essentially consists of polyoxyalkylene and does not contain a hydrolyzable silicon group, and a curing catalyst (III) of the polyoxyalkylene polymer (I) In a room temperature curable composition containing 1 to 5 parts by weight, a polyoxyalkylene polymer (I
A room temperature curable composition, wherein 80% or more of the terminal of I) is a tertiary hydroxyl group and / or a hydroxyl group-containing group having a structure represented by the formula (1). ^{_{-OCH (OH) CH 2 R 1}} ··· (1) In the formula (1), R ¹ represents a monovalent organic group, substituted or unsubstituted 1 to 18 carbon atoms. 2. The room temperature curable composition according to claim 1, wherein the hydrolyzable silicon group in the polyoxyalkylene polymer (I) is represented by the formula (2). —R ³ —SiX _a R ² _3-a (2) In the formula (2), R ² is a substituted or unsubstituted monovalent organic group having 1 to 20 carbon atoms, and R ³ is Is a divalent organic group, X is a hydroxyl group or a hydrolyzable group, a is 1,
2 or 3. 3. The room temperature curable composition of claim 1 or 2, wherein the room temperature curable composition is essentially free of low molecular weight plasticizers. 4. A polyoxyalkylene polymer having a main chain consisting essentially of polyoxyalkylene and containing no hydrolyzable silicon group, wherein 80% or more of the terminals have a tertiary hydroxyl group and / or the formula (1). A polyoxyalkylene polymer (II) which is a hydroxyl group-containing group having a structure represented by
A composition containing as a plasticizer. ^{_{-OCH (OH) CH 2 R 1}} ··· (1) In the formula (1), R ¹ represents a monovalent organic group, substituted or unsubstituted 1 to 18 carbon atoms.