JPH115841A - Silicate compound, silica membrane forming agent and additive for coating material - Google Patents

Abstract

PROBLEM TO BE SOLVED: To obtain a silica membrane coating agent and an additive for a coating material capable of exhibiting excellent characteristics by containing a specific silicate compound excellent in hydrolyzing property. SOLUTION: This silicate compound comprises a silicate compound of formula I [(n) is 1-50 integer; at least one of R1 s is a 2-20C organic group having a higher electron withdrawing property than H at α or β-position to 0 atom, and rest of the R1 s are methyl or ethyl). The R1 groups are each preferably groups of formula II or III [R2 and R3 are each H or a 1-10C hydrocarbon; X is methyl, an aryl, etc., in which at least one H is substituted by Br, Cl or I; R4 is a 1-8C alkyl, phenyl, etc.; R5 is H or methyl; (m) is an integer of 1-4]. The silicate compound is obtained e.g. by performing an ester interchange reaction of a methylsilicate and an ethylsilicate with a corresponding alcoholic compound.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a novel silicate compound and a silica film forming agent and a paint additive using the same.

[0002]

2. Description of the Related Art Ethyl silicate is an ethyl ester of orthosilicic acid (H ₄ SiO ₄ ), which easily reacts with water and hydrolyzes to form a silanol group. By causing a condensation reaction between them, a bond of Si—O—Si is generated. Thus, ethyl silicate is pure and simple silica (S
iO ₂ ) source. For example, it is used as a coating agent that forms a silica film by being applied to a metal surface or a plastic surface. It is also used as a binder to solidify the powder particles. It is also used as a crosslinking agent to be added to silicone rubber or an organic resin having a C-OH group.

[0003] Further, it is used as a paint additive for forming a coating film having excellent stain resistance by being added to a topcoat paint composition (WO 94/06870).
However, depending on the application, the hydrolyzability of ethyl silicate may be insufficient, and a silicate compound having more excellent hydrolyzability is required.

An object of the present invention is to provide a novel silicate compound excellent in hydrolyzability, a silica film-forming agent containing the silicate compound, and a paint additive.

[0005]

Means for Solving the Problems The silicate compound of the present invention is a silicate compound represented by the following general formula (1).

[0006]

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[0007] (wherein, n is an integer of 1 to 50, R ₁
At least one of the above is an organic group having 2 to 200 carbon atoms having a group having a higher electron-withdrawing property than a hydrogen atom at the α-position or the β-position to the oxygen atom, and the remaining R ₁ is a methyl group or an ethyl group It is. Note that whether the electron-withdrawing property is higher than that of a hydrogen atom is affected by the inductive effect and the field effect of the group. For more information about this, see "ADVANCED ORGANIC CHE
MISTRY: REACTIONS, MECHANISMS, AND STRUCTURE SECOND
EDITION ”(issued by McGraw-Hill Engineering)
It is described on page 2.

In the silicate compound of the present invention, R ₁ in the general formula (1) is an organic group represented by the following general formula (2) or an organic group represented by the following general formula (3): Silicate compounds which are the bases are included.

[0009]

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Wherein R ₂ and R ₃ are hydrogen or a hydrocarbon group having 1 to 10 carbon atoms, which may be the same or different, and X is bromine, chlorine or iodine. Two hydrogen-substituted methyl, aryl, vinyl, acetylenyl, acetomethyl, 2-
It is a furyl group, a 2-tetrahydrofuryl group, a phenyl group, a benzyl group, a cyanomethyl group, an acetoxymethyl group, or an alkoxycarbonyl group having 9 or less carbon atoms. )

[0011]

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(Wherein R ₄ is an alkyl group having 1 to 8 carbon atoms, phenyl group or benzyl group, R ₅ is hydrogen or methyl group, and m is an integer of 1 to 4). Is converted to methyl silicate or ethyl silicate by the corresponding alcohol, ie, O 2
It can be produced by transesterification by reacting an alcohol compound having 2 to 200 carbon atoms having a group having a higher electron-withdrawing property than a hydrogen atom at the α-position or the β-position to the oxygen atom of the H group.

When the remaining R ₁ in the above general formula (1) is a methyl group, a methyl silicate having the following structural formula and / or a condensate thereof may be used as the silicate compound as a reaction substrate. it can.

[0014]

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(In the formula, n is an integer of 1 to 50.) When the remaining R ₁ in the general formula (1) is an ethyl group, it is represented by the following structural formula. Ethyl silicate and / or its condensate can be used as a reaction substrate.

[0016]

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(In the formula, n is an integer of 1 to 50.) These methyl silicates and ethyl silicates are, for example, trade names “ES-40” and “ES-28”.
(Manufactured by Colcoat) and trade names "MS-51", "M
S-56 "(manufactured by Mitsubishi Chemical Corporation).

The alcohol compound used for producing the silicate compound of the present invention by the above-mentioned transesterification reaction has at least one hydroxyl group in the molecule as described above, and may be in the α-position or β-position of the oxygen atom of the hydroxyl group. Carbon atoms having a group having a higher electron-withdrawing property than a hydrogen atom
An alcohol compound of 0 can be used. Examples of such alcohol compounds include 2-halogenated ethanols such as 2-chloroethanol, 1-chloro-2-propanol, 2-bromoethanol and 2-iodoethanol; and ethylene cyanohydrin and acetone cyanohydrin. 1- or 2-cyano alcohol; allyl alcohol, propargyl alcohol, 2-butyne-1
2-vinyl or 2-acetylenyl alcohol such as -ol, 3-butyn-1-ol; acetyl alcohol such as acetol, acetoin, diacetone alcohol; furfuryl alcohol, tetrahydrofurfuryl alcohol, phenethyl alcohol, benzyl alcohol; Alkoxycarbonyl methanol such as methyl glycolate and ethyl glycolate; allyl glycol, phenyl glycol, benzyl glycol, dibenzyl glycol, methyl cellosolve, ethyl cellosolve, butyl cellosolve, octyl cellosolve, isopropyl cellosolve, hexyl cellosolve, methyldiglycol, methyltriglycol , Butyl diglycol, butyl triglycol, isobutyl glycol, isobutyl diglycol, hexyl jig Call, 2-ethylhexyl glycol, methyl propylene glycol, methyl propylene diglycol, methyl propylene triglycol,
Propyl propylene glycol, propyl propylene diglycol, phenyl propylene glycol, butyl propylene diglycol, chloroethoxyethanol, chloroethoxyethoxyethanol, methoxybutanol, 3-methyl-3-methoxybutanol, propylene glycol monomethyl ether, propylene glycol monoethyl ether And ether alcohols such as monobutyldiethylene glycol.

As a catalyst for the above transesterification reaction, an acid or a base can be used, if necessary.
Examples of the acid include a Bronsted acid such as hydrochloric acid, sulfuric acid, phosphoric acid, and sulfonic acid, and a Lewis acid such as an organic tin compound. As the base, triethylamine, dimethylbenzylamine, diazabicyclo [2.2.2. Tertiary amines such as octane, 1,8-diazabicyclo [5.4.0] undencene-7 and the like can be used.

The solvent used in the above transesterification reaction may not be particularly used. For example, the solvent may be used by using an excess amount of an alcohol compound as a reaction reagent with respect to the organosilicate. Representative solvents include, for example, aromatic hydrocarbons such as toluene, benzene and xylene, halogenated hydrocarbons such as dichloroethane, ethers such as THF and dioxane, ketones such as methyl ethyl ketone and methyl isobutyl ketone, and acetic acid. Esters such as ethyl and butyl acetate, dimethyl carbamate, acetonitrile and the like. The type and amount of the solvent are not particularly limited, but are preferably 10 times or less based on the total weight of the organosilicate as the reaction substrate and the alcohol compound as the reaction reagent.

The proportion of the organosilicate and the alcohol compound in the above transesterification reaction is at least 1 mol of the alcohol compound with respect to the organosilicate compound. The reaction may be carried out by azeotropically distilling off methanol or ethanol generated by the substitution.

The reaction temperature is not particularly limited, but is generally 0 ° C. to 200 ° C. The reaction time is not particularly limited, but is preferably 24 hours or less. The pressure is generally normal pressure, but if necessary, the pressure may be reduced under reduced pressure to distill off the generated alcohol.

The reaction rate can be determined by measuring the amount of produced methanol or ethanol, NMR spectrum or GC (gas chromatography) analysis. The product obtained as described above is generally a colorless to pale yellow oily substance.

The silicate compound of the present invention can be produced by transesterification by reacting a corresponding alcohol compound with methyl silicates and ethyl silicates as described above. It is not limited to a simple manufacturing method, and may be obtained by another manufacturing method.

The silicate compound of the present invention has excellent hydrolyzability as compared with methyl silicates and ethyl silicates used as a reaction substrate, ie, a raw material. Therefore, a hydrolysis reaction occurs in a shorter time, and desired characteristics can be exhibited.

The silica film forming agent of the present invention is a silica film forming agent containing the silicate compound of the present invention. For example, a silica film can be formed on a plastic surface or the like by using the silicate compound of the present invention or a hydrolyzate thereof as a silica film-forming agent and applying it on a plastic surface or the like. With such a silica coating, for example, wear resistance can be imparted. Further, since the surface of such a silica coating is hydrophilic, the electric resistance value of the surface can be reduced. Therefore, the silica film forming agent of the present invention can be used also as an antistatic agent.

The silicate compound of the present invention can also be used as a binder for solidifying powder particles. Such applications include, for example, binders used in molding agents for casting. Further, it can be used as a binder for an inorganic zinc paint containing metal zinc particles. Such a paint can be used as a rust preventive paint.

The silicate compound of the present invention can be used as a crosslinking agent by adding it to an organic resin such as silicone rubber or an epoxy resin having a C—OH group in the resin.

Further, like the organosilicate and / or the condensate thereof disclosed in International Publication WO94 / 06870, the silicate compound of the present invention is blended in a paint,
By imparting hydrophilicity to the coating film surface, a coating film having excellent stain resistance can be formed. Therefore, the silicate compound of the present invention can also be used as a paint additive.

The silicate compound of the present invention can produce fine powder silica by burning. Therefore, it can be used as a raw material for high-purity silica.

The silicate compound of the present invention can be added to a resin and used as a dehydrating agent for dehydrating water. Further, it can be used as a raw material for glass synthesis by a sol-gel method or as a polyolefin synthesis polymerization catalyst.

[0032]

EXAMPLE 1 60.5 g (0.081 mol) of a condensate of ethyl silicate (trade name "ES-40", manufactured by Colcoat Co., Ltd., average molecular weight: 745, number of ethoxy groups per molecule: 12) )
19.5 g of 2-chloroethanol (0.244 mo
l) was added, and the temperature was raised from 100 ° C to 140 ° C over 6 hours. Here, no catalyst was used. When the distillate was analyzed by GC, it was only ethanol, and the amount of the distillate was 7.0 g. The conversion was calculated from the amount of the distillate to be 63%. Therefore, the transesterification of 2-chloroethanol is carried out with ethyl silicate E
The number was 1.9 per molecule of S-40. The viscosity of the obtained product measured at 25 ° C. was 4.5 cps.

Examples 2 to 11 As shown in Table 1, the amount of ethyl silicate and the type and amount of alcohol were changed, and if necessary, a silicate compound was prepared in the same manner as in Example 1 above, using a solvent and a catalyst. Manufactured. Table 1 shows the reaction rates of the obtained silicate compounds and the number of exchanges of the alcohol per molecule of ES-40. Table 1 shows the viscosity of the obtained product at 25 ° C.

[0034]

[Table 1]

Evaluation of hydrolyzability The silicate compounds of Examples 1 to 11 obtained as described above were evaluated for hydrolyzability. In Example 1, the evaluation of the hydrolyzability was carried out in a 4 ml Vessel bottle at the following mixing ratio with the silicate compound, water, dioxane,
The measurement was performed by adding 2-ethylhexanoic acid and dimethyllaurylamine, and measuring the gelation time at room temperature (about 20 ° C.).

(Compounding ratio of Example 1) Silicate compound 1.50 g Water 0.4 g Dioxane 1.97 g 2-Ethylhexanoic acid 0.0053 g Dimethyllaurylamine 0.0079 g Total 3.8883 g

In the other examples, the silicate compound was added so as to have the same molar amount as the above-mentioned mixing ratio.
The mixing ratio of dioxane was changed so that the total amount was the above-mentioned total amount.

In the above mixing ratio, the ratio of alkoxy group / water is 1/1 (molar ratio), the ratio of acid / amine is 1/1 (molar ratio), and the total amount of acid and amine is 0.34% by weight based on the total amount. It is blended so that

As Comparative Example 1, the hydrolysis of ethyl silicate ES-40, which is a raw material of the silicate compound, was evaluated in the same manner. Table 2 shows the evaluation results.

[0040]

[Table 2]

As is clear from the results in Table 2, the silicate compounds of Examples 1 to 11 according to the present invention have a significantly shorter gelation time than the ethyl silicate of Comparative Example 1, and have excellent hydrolyzability. You can see that there is.

Evaluation of Solubility and Compatibility The silicate compounds of Examples 1 to 11 were evaluated for solubility and compatibility. Solubility is as follows:
Using 0, the silicate compound was added to the swazole 310 so that the ratio of the silicate compound / swazole 310 was 1/9, and it was visually confirmed whether or not the mixture became white turbid when stirred and mixed. What is mixed in the transparent state is marked with ○,
Those that became cloudy were evaluated as x marks.

As for the compatibility, aliphatic alcohol-modified isocyanate (trade name “Tronate MTK-3” manufactured by Sanyo Chemical Industries, NV 61% by weight, solvent: Swazole 3)
10 / Solvesso 100 = 6/4), and the silicate compound / tronate MTK-3 was mixed at a ratio of 1/2 to evaluate whether the mixture became cloudy. A sample in which the mixture was transparent was marked with a circle, and a cloudy one was marked with a cross.

Table 3 shows the evaluation results of solubility and compatibility.

[0045]

[Table 3]

Examples 12 to 22 Silicate compounds were produced in the same manner as in Example 1 above, using silicates and alcohols as shown in Table 4 and optionally using solvents and catalysts. Table 4 shows the conversion, the number of alcohol exchanges per silicate molecule, and the viscosity at 25 ° C. of the obtained silicate compound.

In Table 4, "ES-48",
"MS-56" and "Amber list 15E" are as shown below. "ES-48": ethyl silicate high molecular weight type, molecular weight about 1300, manufactured by Colcoat "MS-56": methyl silicate, molecular weight about 130
0, "Amberlyst 15E" manufactured by Mitsubishi Chemical Corporation: sulfonic acid type ion exchange resin, manufactured by Organo Corporation

[0048]

[Table 4]

[0049]

The silicate compound of the present invention has excellent hydrolyzability as compared with methyl silicate or ethyl silicate. Therefore, it exhibits excellent properties in various uses such as a silica film forming agent and a paint additive.

──────────────────────────────────────────────────続 き Continued on the front page (51) Int.Cl. ⁶ Identification code FI C09D 183/02 C09D 183/02

Claims (6)

[Claims] 1. A silicate compound represented by the following general formula (1). Embedded image (In the formula, n is an integer of 1 to 50, and at least one of R ₁ has 2 to 20 carbon atoms having a group having a higher electron-withdrawing property than a hydrogen atom at the α-position or the β-position to the oxygen atom.
0 is an organic group, and the remaining R ₁ is a methyl group or an ethyl group. ) 2. An organic group represented by the following general formula (2) or R ₁ in the general formula (1):
The silicate compound according to claim 1, which is an organic group represented by the formula: Embedded image (Wherein R ₂ and R ₃ are hydrogen or a hydrocarbon group having 1 to 10 carbon atoms and may be the same or different from each other, and X is bromine, chlorine, or iodine and at least one hydrogen is Substituted methyl, aryl, vinyl,
Acetylenyl group, acetomethyl group, 2-furyl group, 2-
It is a tetrahydrofuryl group, a phenyl group, a benzyl group, a cyanomethyl group, an acetoxymethyl group, or an alkoxycarbonyl group having 9 or less carbon atoms. ) (In the formula, R ₄ is an alkyl group having 1 to 8 carbon atoms, a phenyl group or a benzyl group, R ₅ is a hydrogen or a methyl group, and m is an integer of 1 to 4.) 3. The silicate compound according to claim _1, wherein the remaining R ₁ is a methyl group. 4. The silicate compound according to claim _1, wherein the remaining R ₁ is an ethyl group. 5. A silica film-forming agent comprising the silicate compound according to claim 1. 6. An additive for an organic paint, comprising the silicate compound according to claim 1 as a main component.