JP3115049B2 - Curable composition - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a room temperature curable composition which cures in the presence of moisture.

[0002]

2. Description of the Related Art Conventionally, a method of curing various compounds having a terminal hydrolyzable silicon group, such as a modified silicone resin, and using the same for sealing materials, adhesives, etc. is well known. Is an industrially useful method.

[0003]

Among the compounds having a terminal hydrolyzable silicon group, particularly as the hydrolyzable silicon group,
In the case of a compound having an alkoxysilyl group, a so-called curing catalyst is usually used to impart room-temperature curability.

As such curing catalysts, metal salts of carboxylic acids, acidic or basic compounds and the like are generally known, and among them, tetravalent organotin compounds and / or 2
Valent tin carboxylates are common.

However, dibutyltin dilaurate, dibutyltin Geographic click Tano benzoate, when using tetravalent organotin compounds such as dibutyltin diacetate as a curing catalyst of a compound having an alkoxysilyl group as a hydrolyzable silicon group, the curing reaction is slow And the cured product has poor compression set.

On the other hand, when a divalent tin carboxylate such as tin octylate is used as a curing catalyst, curing is fast and the compression set is improved, but the moisture resistance of the tin compound itself is improved. However, there is a drawback that it is difficult to use it particularly as a one-pack type sealing material. The present invention seeks to overcome the above disadvantages.

[0007]

Means for Solving the Problems The present invention, to the organic polymer and its 100 parts by weight of at least one hydrolyzable silicon group in a molecule, an organic tin compound represented by the following general formula (1) ( a), 0. the reaction product obtained by reacting an organic tin compound represented by the following general formula (2) (b) and an organic dicarboxylic acid anhydride having 1 to 20 carbon atoms 01-5
An object of the present invention is to provide a room temperature curable composition characterized by containing by weight. The monovalent hydrocarbon group _{^{R 1 2 SnO ··· (1)}} R 2 2 Sn (OCOR 3) 2 ··· (2) ( wherein R ^1, R ^2, R ³ having 1 to 20 carbon atoms Show)

In the present invention, the organic polymer having at least one hydrolyzable silicon group in the molecule is a compound which undergoes a hydrolysis and cross-linking reaction by moisture to change into a rubber-like elastic material.

[0009] Such moisture-curable compounds include:
Many compounds have been studied so far, for example, JP-A-3-47820, JP-A-3-72027, JP-A-3-79627, and JP-B-46-307.
No. 11, JP-B-45-36319, JP-B-4
It has been proposed in JP-A-6-17553.

In particular, the hydrolyzable silicon-group-containing organic polymer of the present invention is preferably produced by introducing a hydrolyzable silicon group into the terminal of a polyoxyalkylene compound having a functional group as described below. . Such a compound is liquid at room temperature, and the cured product retains flexibility even at a relatively low temperature, and has preferable characteristics when used as a sealing material, an adhesive or the like.

The polyoxyalkylene compound is obtained by reacting a monoepoxide such as an alkylene oxide with an initiator such as a hydroxy compound having at least one hydroxyl group in the presence of a catalyst such as an alkali metal catalyst, a double metal cyanide complex catalyst, and a metal porphyrin catalyst. Hydroxyl-terminated ones produced by the above method are preferred. The number of functional groups of the polyoxyalkylene compound is preferably 2 or more, and particularly preferably 2 or 3.

[0012] As the polyoxyalkylene compound, specifically, polyoxyethylene compounds, polyoxypropylene compounds, polyoxybutylene compounds, polyoxy hexylene compounds, polyoxytetramethylene compounds and this <br/> these co polymer can be mentioned up.

Particularly preferred polyoxyalkylene compounds are polyoxypropylene diol and polyoxypropylene triol. When used in the following methods (a) and (d), olefin-terminated polyoxyalkylene compounds such as allyl-terminated polyoxypropylene monol can also be used.

The hydrolyzable silicon group in the present invention may be any silicon group that undergoes hydrolysis and cross-linking reaction in the presence of moisture to form a siloxane bond, and generally known hydrolyzable silicon groups are used. it can.

[0015] For example, it is silicon groups shown by the general formula (3). ^{_{-SiX a R 4 3-a ···}} (3)

[0016] wherein R ⁴ is a monovalent organic group substituted or unsubstituted 1 to 20 carbon atoms, preferably an alkyl group, a phenyl group or a fluoroalkyl group having 8 or less carbon atoms.
Particularly preferred are a methyl group, an ethyl group, a propyl group , a butyl group, a hexyl group, a cyclohexyl group, a phenyl group and the like.

[0017] X is a hydrolyzable group, eg if a halogen atom, an alkoxy group, an acyloxy group, an amide group, an amino group, an amino group, there are etc. ketoximate group.

Among these, the number of carbon atoms of the hydrolyzable group having a carbon atom is preferably 6 or less, and particularly preferably 4 or less. Preferred examples of the hydrolyzable group include a lower alkoxy group having 4 or less carbon atoms, particularly a methoxy group, an ethoxy group and a propoxy group . a is 1, 2 or 3, and particularly preferably 2 or 3.

The method of introducing the silicon group represented by the general formula (3) into the polyoxyalkylene compound is not particularly limited, but for example, it can be introduced by the following method.

[0020] (a) to that introduced an olefin group at the terminal of the polyoxyalkylene compound having a functional group, a method of reacting a hydrosilyl compound shown by the general formula (4). ^{_{HSiX a R 4 3-a ···}} (4) ( wherein R ^4, X, a is the same)

[0021] As a method for introducing wherein olefinic groups, a compound having an unsaturated group and a functional group is reacted at the terminal hydroxyl group of the polyoxyalkylene compound, an ether bond, an ester bond, urethane bond, carbonate bond, etc. method of bonding by, or when polymerizing alkylene oxide, such as a method of introducing an olefin group in the side chain are exemplified by copolymerization by adding an olefin group-containing epoxy compound such as allyl glycidyl ether.

[0022] (b) a method of reacting polyoxyalkylene terminus formula alkylene compound (5) in shown the compounds having a functional group. R ⁴ _3-a- SiX _a -R ⁵ NCO (5) (wherein R ⁴ , X and a are the same as above. R ⁵ has 1 to 1 carbon atoms)
7 divalent hydrocarbon group. )

[0023] (c) after the end of the polyoxyalkylene compound having a functional group is reacted with a polyisocyanate compound such as tolylene diisocyanate and the isocyanate group-terminated silicon to be shown by the general formula (6) to the isocyanate groups A method of reacting a W group of a compound.

[0024] ^{_{R 4 3-a -SiX a -R}} 5 W ··· (6) ( wherein ^{R 4, R 5, X,} a are as .W the hydroxyl group,
An active hydrogen-containing group selected from a carboxyl group, a mercapto group and an amino group (primary or secondary). )

[0025] (d) introducing an olefin group at the terminal of the polyoxyalkylene compound having a functional group, and the olefinic group, silicon compounds W is shown <br/> by the above general formula is a mercapto group (6) Reacting a mercapto group of The number of hydrolyzable silicon groups is 50% or more on average in all terminal groups,
In particular, it is preferable to contain 70% or more.

As the organic polymer having a hydrolyzable silicon group in the present invention, an organic polymer having a molecular weight of 8,000 to 30,000 can be used . The organic molecular weight of the polymer is hard and cured product is lower than 8000, and the elongation is as low flexibility of molecular weight cured product is exceeded 30,000 Oyo <br/> beauty elongation is no problem, the The viscosity of the polymer itself becomes extremely large, and the utility becomes low. The molecular weight is especially 10
000-30000 is preferred.

The organotin compounds used in the present invention the upper Symbol organotin compound represented by the general formula (1) (a) and the upper <br/> Symbol organotin compound represented by the general formula (2) (b) It is .

In the formula, R ¹ and R ² represent a monovalent hydrocarbon group having 1 to 20 carbon atoms . Specific examples include a methyl group, an ethyl group, a propyl group, a butyl group, a hexyl group, an octyl group, and a phenyl group, but a methyl group, a butyl group, and an octyl group are preferable in terms of economy.

[0029] Preferably the A sills group having 1 to 20 carbon atoms Specific examples of A sill group containing in R ³ formula, among which an acetyl group, 2-ethyl-hexanoyl group, lauroyl group is preferable from the viewpoint of economy .

As the organic dicarboxylic anhydride in the present invention , an anhydride of an aliphatic, alicyclic or aromatic dicarboxylic acid having 1 to 20 carbon atoms can be used. Specifically, succinic anhydride, maleic anhydride, phthalic anhydride, Te tiger tetrahydrophthalic anhydride, although f hexa hydro phthalic anhydride, etc. can be exemplified, but the invention is not limited thereto.

The organic tin compounds represented by the organotin compound represented by the above following general formula (1) used in the present invention (a) and the above following general formula (2) (b) is the hydrolyzable silicon groups It is known to act as a catalyst for hydrolysis and crosslinking reactions .

However, the organotin compound (a) cannot be used as a catalyst because it is practically insoluble in the organic polymer having a hydrolyzable silicon group used in the present invention. There were problems that the catalytic activity was not always satisfactory and that the compression set of the cured product was poor.

In the present invention, a reaction product of these two kinds of organotin compounds and an organic dicarboxylic anhydride is used as a catalyst. The reaction product is used as a catalyst for a hydrolysis reaction and a crosslinking reaction of a hydrolyzable silicon group. each it becomes either bright et showing a significantly higher activity than used alone, leading to the present invention.

In the present invention, the organotin compound (a), the organotin compound (b) and the organic dicarboxylic anhydride are mixed at an arbitrary ratio and heated to 80 to 180 ° C. to obtain a reaction mixture in several hours. Is preferred.

The mixed-percentage of this time, the organic tin compounds,
It is preferable to use the organic tin compound (b) in a range of 0.1 mol to 3 mol and the organic dicarboxylic anhydride in a range of 0.01 mol to 0.5 mol per 1 mol of the organic tin compound (a).

[0036] In the present invention, at least one hydrolyzable silicon group the reaction with the organotin compound (a) and <br/> organotin compound (b) an organic dicarboxylic acid anhydride, in the molecular to the organic polymer 100 parts by weight having, Ru using 0.01 to 5 parts by weight. More preferably, it is 0.1 to 3 parts by weight.

When the reaction product has a high viscosity or becomes semi-solid, it can be diluted with an appropriate diluent. As such a diluent, various solvents commonly used and compounds known as plasticizers can be used.

The composition of the present invention may further contain various known fillers, plasticizers, additives and the like.

[0039] As fillers, fumed silica, precipitated silica, fillers such as silicic anhydride, hydrous silicic acid, carbon black, calcium carbonate, magnesium carbonate, diatomaceous earth, calcined clay, clay, talc, titanium oxide, bentonite Fillers such as organic bentonite, ferric oxide, zinc oxide, activated zinc white, hydrogenated castor oil and shirasu balloon , and fibrous fillers such as asbestos, glass fiber and filaments can be used.

As the plasticizer, dioctyl phthalate,
Phthalates dibutyl phthalate, butyl benzyl phthalate; glycol esters such as pentaerythritol esters; dioctyl adipate, succinate di <br/> isodecyl, dibutyl sebacate, fatty acid esters such as butyl oleate; trioctyl phosphate, phosphoric acid esters such as tricresyl phosphate, epoxy soybean oil, epoxy plasticizers such as epoxy stearic acid benzyl; chlorinated paraffin or the like can be used singly or in combination.

As the additives, there can be used adhesion imparting agents such as phenolic resins and epoxy resins, pigments, various antioxidants, ultraviolet absorbers and the like.

The room temperature curable group composition as the present invention can be used in particular for elastic sealants, as adhesives.

[0043]

EXAMPLES EXAMPLE elevation gel of the present invention below is not intended to be limited thereto.

Reference Example 1 31.6 g (0.05 mol) of dibutyltin dilaurate
To, dibutyltin oxide 24. 9g (0. 10 mol) and phthalic anhydride 1. 5g (0. 01 mol) was added, with stirring in a glass reactor, under nitrogen atmosphere,
After heating at 170 ° C. for 3 hours, insoluble matter was filtered off to obtain oily reaction product A.

Reference Example 2 Dibutyltin diacetate 17.6 g (0.05 mol)
With respect to 54.2 g of dioctyltin oxide (0.15
Mol) and Te tiger tetrahydrophthalic anhydride 3.0 g (0.
After heating at 170 ° C. for 3 hours under a nitrogen atmosphere while stirring in a glass reactor, the insoluble matter was filtered to obtain an oily reaction product B.

[0046] [Reference Example 3] for dibutyltin Geo-click Tano benzoate 25. 9g (0. 05 mol), dibutyl tin oxide 12. 5g (0. 0
5 mol) and maleic anhydride 1. 0 g (0.01 mol) was added, with stirring in a glass reactor, under nitrogen atmosphere, was heated 3 hours at 170 ° C., and filtered the insoluble matter, Oily reaction C was obtained.

Examples 1 to 3 Polyoxypropylene polymer 100 having an average molecular weight of 20,000 and having a methyldimethoxypropyl group at 90% of the molecular terminals
130 parts by weight of calcium carbonate, 20 parts by weight of titanium oxide, 20 parts by weight of dioctyl phthalate, 5 parts by weight of hydrogenated castor oil, and 1 part by weight of a phenolic antioxidant are added to parts by weight, and under a condition where moisture does not enter. After kneading, Reference Examples 1 to
The reaction A~C obtained in 3 was added each 1 part by weight, mixed well, and left them to room temperature, beauty 48 Oyo after 24 hours
The cured state after time was observed. Table 1 shows the obtained results.

Comparative Examples 1 to 3 In place of the reactants A to C in the above Examples, dibutyltin dilaurate, dibutyltin diacetate, and 1 part by weight of dibutyltin oxide were used, and the cured state was observed. Table 1 shows the obtained results.

The evaluations in Table 1 are as follows. ○ ・ ・ ・ Good △ ・ ・ ・ Somewhat sticky × ・ ・ ・ Some sticky

[0050]

[Table 1]

[0051]

The curing catalyst used in the present invention is excellent as a curing catalyst for a room temperature curable composition containing a hydrolyzable silicon group-containing polymer as a main component, and a tin compound conventionally used is used. This has the effect that the composition cures faster than the composition.

Continuation of front page (56) References JP-A-4-57850 (JP, A) JP-A-60-8345 (JP, A) JP-A-58-111855 (JP, A) (58) Fields investigated (Int .Cl. ⁷ , DB name) C08L 1/00-101/16

Claims (3)

(57) [Claims] An organic tin compound (a) represented by the following general formula (1) and an organic tin compound (a) represented by the following general formula (1) are added to 100 parts by weight of an organic polymer having at least one hydrolyzable silicon group in a molecule. organic tin compounds represented by) (b) and room temperature curing, characterized in that it contains 01 to 5 parts by weight 0.1 the reaction product obtained by reacting an organic dicarboxylic acid anhydride having 1 to 20 carbon atoms Composition. The monovalent hydrocarbon group _{^{R 1 2 SnO ··· (1)}} R 2 2 Sn (OCOR 3) 2 ··· (2) ( wherein R ^1, R ^2, R ³ having 1 to 20 carbon atoms Show) 2. An organic polymer having a molecular weight of 8,000 to 3
0000 polyoxyalkylene compound.
2. The room temperature curable composition according to item 1. 3. A hydrolyzable silicon group is room temperature curable composition according to claim 1 or 2, a group represented by the following general formula (3). ^{_{-SiX a R 4 3-a ···}} (3) ( the formula in R ⁴ is substituted or having from 1 to 20 carbon atoms unsubstituted monovalent hydrocarbon group, X is a hydrolyzable group, a is 1, 2 or 3
Is shown. )