JPH06340709A - Organic-inorganic fused product and its production - Google Patents

Abstract

PURPOSE:To provide an organic-inorganic fused product capable of enhancing the adhesion of coatings to metal raw materials, giving coating films good in adhesion without requiring any preliminary treatment, and useful for the coatings, etc., by reacting a hydroxyl group or acyloxy group-having organic polymer with a metal alkoxide (derivative). CONSTITUTION:An organic polymer having hydroxyl groups and/or acyloxy groups of the formula (R is alkyl) (e.g. ethyl cellulose) is reacted with a metal alkoxide of formula: M(OR')n (M is Si, Al, Zr, Y, Ti, etc.: R' is alkyl; n is 2-4) (e.g. tetraethoxy-silane) or its derivative in ethanol or acetone solvent under a refluxing condition for 3hr in N2 gas with the agitation of the reaction solution to produce the objective organic-inorganic fused product having the bonds of formula: M-O-C, capable of improving the adhesion of organic coatings to metal raw materials, giving coating films good in adhesion, not requiring a preliminary treatment when coated, and useful for the coatings used for coating the metals.

Description

Detailed Description of the Invention

[0001]

FIELD OF THE INVENTION This invention relates to organic-inorganic fusions and to coatings applied to metals.

[0002]

2. Description of the Related Art The sol-gel method enables the synthesis of glass and ceramics at a relatively low temperature and is applied to the synthesis of inorganic materials having a new composition.

In recent years, attempts have been made to synthesize not only inorganic materials, but also new materials having the characteristics of both inorganic and organic substances. This type of material has been studied by researchers of inorganic materials by using organically modified silicates.
d silicate), and is called a ceramer by researchers of organic polymers, and is generally called an organic-inorganic fusion.

The characteristics of inorganic substances are strength, heat resistance, optical characteristics, high density, etc., while the characteristics of organic substances are elasticity,
It has flexibility, plasticity, gas permeability and low density.

By combining the two, it is possible to create a new material that makes the best use of the both and makes up for the shortcomings, and its application destinations are optical materials, protective films, electronic materials, reinforced polymers, elastic bodies, sensors, catalysts, contacts. Lenses, filters, etc. have been proposed.

The research on such organic-inorganic fusion is underway in a system in which an organic monomer is reacted with an inorganic monomer such as a metal alkoxide.

Examples of organic-inorganic fusions include Phili
There is a hard contact lens material synthesized by pp and Schmidt. The contact lens needs to have high oxygen permeability, and a dimethylsiloxane skeleton is suitable for this.

[0008] Further, an alcohol group ≡ which gives a wetting property to water so that tear proteins do not adhere.
COH must be included.

[0009] In order to obtain a transparent material which leaves the group responsible for such properties and has improved mechanical properties, Schmi
dt et al. utilized the sol-gel process.

Epoxy silane Methacryloxysilane (CH ₃ O) ₃ SiCH ₃ H ₆ OOC
C (CH ₃ ) = CH ₂ , titanium alkoxide Ti (O
R ') ₄ is reacted in a mixed solution containing 90: 5: 5 mol%, and 20 to 30 mol% of a methacrylate monomer and a peroxide polymerization catalyst are added to the mixture to further advance the reaction to form a homogeneous viscous solution. It was heated and cured at a temperature of 150 ° C. or lower.

Methacrylate polymerizes to polymethylmethacrylate, binding siloxane bonds.

This material is a transparent, homogeneous, dense solid, has high tensile strength, flexibility, has a high oxygen permeability, and has the characteristics that proteins are hard to adhere to the lens because it is well wetted by tears. It was a thing.

By the way, paint is considered as one of the fields in which the characteristics of the organic-inorganic fusion material can be sufficiently exhibited.

Although there are various purposes for coating, the purpose is to protect an object, which is largely a base material, and at the same time, to increase durability and beautify it. Specifically, there are rust preventive paints, ship bottom paints, insulating paints, luminescent paints, electrodeposition paints and the like.

Further, the properties required for the coating material also differ depending on the purpose, and include, for example, quick-drying property, hardness, flexibility, adhesion property, color development property, gloss property, non-adhesiveness (stickiness), water resistance, alkali resistance, It has heat resistance. As described above, the properties required of the coating material are wide ranging from organic properties to inorganic properties.

The objects to be painted are buildings,
From large items such as ships and bridges to various machinery, furniture, small items such as juice containers, and daily necessities.

Therefore, various materials can be used as the base material, and there are a wide range of organic materials such as wood and plastics, metals such as iron and aluminum, and ceramics such as concrete.

Among these, in the coating of the metal base with the organic paint, various pretreatments are performed on the metal base in order to improve the adhesion of the coating.

As the pretreatment, for example, the surface of the base material may be etched, roughened by spray brush or rough polishing, or a base may be formed by chromate treatment or undercoating.

There is no example of organic-inorganic fusion for the purpose of paint, and as a close one, an alcohol of monomethylalkoxylane on a steel plate in JP-A-64-68477, JP-A-2-3479 and JP-A-2-125878. There is an example in which a film made of an organic substance and Si is produced by applying a solution.

[0021]

In general, the reaction of an organic-inorganic fusion product by copolymerization of an organic monomer and an inorganic monomer is complicated, so that it is difficult to control the reaction, and the obtained fusion product is further polymerized. Therefore, the addition of a polymerization initiator and polymerization under high pressure are required, and the process is complicated. Therefore, an organic-inorganic fusion material that can simplify the synthesis process is desired.

In the field of paints, basically, the interfacial bond between the metal base (M) and the organic paint is MO ... H.
Since it is a hydrogen bond or a van der Waals bond, the bond strength is limited.

In order to improve the adhesiveness in the coating on the metal base material, the pretreatment as described above is performed to increase the contact interface between the metal base material and the coating material. Essentially, the weak bond strength has been supplemented by forming a base having good properties.

That is, in the conventional organic coating, sufficient adhesion could not be obtained without pretreatment of the metal base.

[0025]

DISCLOSURE OF THE INVENTION The present invention has the object of solving the above problems by --OH group, and / or Use of an organic-inorganic fusion product having an M—O—C bond obtained by reacting an organic polymer having (R is an alkyl group) with a metal alkoxide (M (OR ′) _n ) or a derivative thereof It is a thing.

The manufacturing method will be described in more detail below.

A metal alkoxide or its derivative is added to an organic solvent such as alcohol or acetone, the mixture is stirred lightly, an organic polymer is added, and the mixture is heated under reflux in N ₂ gas to obtain a solution.

The organic-inorganic fusion body of the present invention can be produced by removing the solvent of this solution by evaporation.

When the organic-inorganic fusion material of the present invention is used as a coating material, the solution alone or after mixing the solution with a pigment or the like is directly applied to the base material and dried.

Examples of the metal atom M used in the present invention include Si, Al, Zr, Y and Ti.

Examples of the alkoxide of the above-mentioned element used as a starting material include methoxide, ethoxide, butoxide, propoxide, methoxyethoxide and ethoxyethoxide.

The alkoxide derivative is one in which a part of the alkoxy group is substituted with alkanolamine, alkylalkanolamine, β-diketone, β-ketoester, alkyl group and the like.

The organic polymer in the present invention means --OH
Groups, and / or Examples thereof include ethyl cellulose, cellulose nitrate, cellulose acetate, cellulose acetate butyrate, cellulose propionate, polyvinyl acetate, polyvinyl alcohol, chitin, chitosan, and the like.

[0034]

In the present invention, by inserting the metal species (M) into the organic substance at the atomic level, a chemical bond of M-O-M 'can be formed with the metal substrate (M'), and this chemical bond is hydrogen. Since it is stronger than the bond or the Van der Waals bond, the adhesive property is improved.

[0035]

Example 1 An organic polymer as shown in Table 1 and a metal alkoxide or its derivative are used.

After adding the metal alkoxide or its derivative into the solvent of ethanol or acetone and stirring lightly,
Add an organic polymer and heat to reflux for 3 hours in N ₂ gas.

The colorless and transparent solution thus obtained confirms MO bonds by IR (infrared absorption spectrum).

As a typical example, IR results of a fusion product using ethyl cellulose as an organic polymer and tetraethoxysilane as a metal alkoxide are shown.

FIG. 1 shows the IR of ethyl cellulose, and FIG. 2 shows the IR of the ethyl cellulose-Si fusion product of the present invention.

The ethyl cellulose --O-- seen in FIG.
H and However, it is decreasing in FIG.

That is, ethyl cellulose reacts with tetraethoxysilane to form an organic-inorganic fusion material having a Si--O--C bond.

Table 1 shows a list of decomposition temperatures of the obtained organic-inorganic fusion material.

[0043]

Comparative Example 1 An organic polymer is added to an ethanol or acetone solvent, and then heated under reflux in N ₂ gas for 3 hours. The decomposition temperatures are shown in Table 1.

[0044]

Example 2 The characteristics of the solution of Example 1 as a coating material were investigated.

The solution obtained in Example 1 is applied onto a metal substrate three times with a brush. After drying in air at room temperature for 10 hours, a cross-cut test was conducted to examine the adhesiveness.

1m to reach the substrate by diamond needle on the coating film
Make 100 (10 x 10) squares in a square.

Cellotape was attached to this, and immediately peeled off, and the number of eyes left without peeling off the coating film was evaluated. Second result
Shown in the table.

[0048]

Comparative Example 2 After adding an organic polymer or a monomer to an ethanol or acetone solvent, the mixture is heated under reflux in N ₂ gas for 3 hours.

The colorless and transparent solution thus obtained is applied onto a metal substrate three times with a brush. After drying in air at room temperature for 10 hours, a cross-cut test was conducted in the same manner as in Example 2 in order to examine the adhesiveness. The results are shown in Table 2.

[0050]

[Table 1]

[0051]

[Table 2]

[0052]

[Table 3]

[0053]

[Table 4]

[0054]

According to the present invention, the process can be simplified by fusing the organic polymer and the metal alkoxide or its derivative at the atomic level.

Further, by using the organic-inorganic fusion material of the present invention, a coating film having good adhesion can be obtained, and as a result, pretreatment is not required.

[Brief description of drawings]

FIG. 1 is an IR of ethyl cellulose.

FIG. 2 is an IR of an organic-inorganic fusion product obtained by reacting ethyl cellulose with tetraethoxysilane.

Claims (2)

[Claims] 1. An —OH group and / or An organic-inorganic fusion product having an M-O-C bond obtained by reacting an organic polymer having (R is an alkyl group) with a metal alkoxide (M (OR ') _n ) or a derivative thereof. 2. A metal coating material using the organic-inorganic fusion material according to claim 1.