JPS6136847B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a metal-containing curable resin composition having an ionic bond, and more specifically to a metal-containing curable resin composition having the general formula (1). (However, M represents a divalent metal) An ion characterized by being added to an epoxy resin in a molar ratio of a divalent metal salt of lactic acid and a dibasic acid anhydride represented by 1:6 to 40. The present invention relates to a metal-containing curable resin composition having a bond. An object of the invention is to provide a metal-containing curable resin composition having ionic bonds that is extremely useful industrially and yielding a cured product having excellent physical properties, particularly good adhesive properties.

Conventionally, a commonly used method for introducing ionic bonds into polymer chains is to first introduce a polymer having a functional group capable of forming an ionic bond such as a carboxyl group at the terminal or side chain using a known method. There is a method in which the polymer is synthesized and then the functional groups of the polymer are neutralized by adding a metal ion generating agent. However, this method has drawbacks such as the neutralization reaction not progressing sufficiently and the removal of unreacted metal ion generators, and the presence of unreacted metal ion generators that are not removed causes the polymer to become opaque. There are cases.
Furthermore, by-products such as water are produced by the neutralization reaction. In particular, it is extremely difficult to apply this method to effectively introduce ionic bonds into three-dimensional polymers.

As a result of intensive study on an advantageous method for producing an excellent metal-containing cured resin containing ionic bonds, the present inventor found that the general formula ( By using the divalent metal salt of lactic acid shown in 1) as a component of the curable resin composition, excellent physical properties can be obtained in which ionic bonds are introduced into the polymer chain in one step without the addition of a catalyst. The inventors discovered that it is possible to synthesize a metal-containing cured resin having particularly good adhesive properties, leading to the present invention.

In addition, conventionally, metal salts of organic carboxylic acids such as acetic acid, octylic acid, stearic acid, oleic acid, and naphthenic acid have been added to epoxy resin compositions using acid anhydrides as curing agents simply for the purpose of promoting curing. It is known that in the metal-containing curable resin composition having ionic bonds of the present invention, the divalent metal salt of lactic acid represented by the general formula (1), which is one of its components, has a metal carboxylate group in the molecule. and two hydroxyl groups, it accelerates the curing reaction and is incorporated into the cured resin to introduce ionic bonds into the polymer chain, resulting in a cured product with excellent ionic bond introduction effects. It is characterized by its physical properties, particularly good adhesiveness.

The divalent metal salt of lactic acid represented by the general formula (1) used in the present invention includes alkaline earth group metal salts and zinc group metal salts, but considering problems such as industrial availability and environmental pollution. Then magnesium salt,
Calcium salts, zinc salts, etc. are preferred.

Examples of dibasic acid anhydrides which are one component of the metal-containing curable resin composition in the present invention include phthalic anhydride, maleic anhydride, hexahydrophthalic anhydride, tetrahydrophthalic anhydride, succinic anhydride, tilnadic anhydride, and Examples include derivatives thereof. These can be used alone or
Two or more types may be used in combination.

The epoxy resin used in the present invention is one used in general cured epoxy resins,
The epoxy resin having an average of two or more epoxy groups in one molecule may be used alone or as a mixture of two or more, and in some cases may be a mixture with a monoepoxy compound. Examples of epoxy resins containing two or more epoxy groups in one molecule include bisphenol A type epoxy resins, phthalate glycidyl ester type epoxy resins, hexahydrophthalate glycidyl ester type epoxy resins, polyalkylene ether type epoxy resins, and fatty acids. Examples include group diepoxy compounds. Examples of the epoxy resin containing three or more epoxy groups include tris-2,3-epoxypropyl-isocyanurate, glycerin triether type epoxy resin, novolak type epoxy resin, and the like. Furthermore, examples of the monoepoxy compound include phenyl glycidyl ether, styrene oxide, and the like.

Now, the divalent metal salt of lactic acid and the dibasic acid anhydride represented by the general formula (1) are mixed into an epoxy resin in a molar ratio of 1:6 to 40. The novel metal-containing curable resin composition of the present invention can be obtained by adding the divalent metal salt of lactic acid represented by the general formula (1) and the dibasic acid anhydride. You can add things at the same time,
Each may be added separately. In addition, by changing the quantitative ratio of each component in the metal-containing curable resin composition, the amount of ionic bonds in the resulting cured resin,
Terminal groups, crosslink density, etc. can be changed.
That is, regarding the ratio of divalent metal salt of lactic acid and dihydrochloric acid anhydride represented by general formula (1), when the ratio of dibasic acid anhydride to divalent metal salt of lactic acid decreases, the resulting cured product The crosslinking density becomes low, and when it increases, the crosslinking density becomes high. Furthermore, when the proportion of the divalent metal salt of lactic acid and the dibasic acid anhydride in the epoxy resin decreases, the resulting cured product will have a high proportion of terminal hydroxyl groups, whereas if the proportion of the divalent metal salt of lactic acid and dibasic acid anhydride becomes too large, the proportion of terminal carboxyl groups will increase. will increase. In the present invention, when the molar ratio of the divalent metal salt of lactic acid represented by the general formula (1) and the dibasic acid anhydride is 1:6 to 40, a cured product with excellent physical properties can be obtained. If the ratio is less than 1:6, the crosslinking density of the resulting cured product will be too low, and if it is more than 1:40, the amount of ionic bonds will be so small that the effect of introducing ionic bonds will not be apparent. There is no particular restriction on the blending ratio of the dibasic acid anhydride to the epoxy resin, but in general, a cured product with excellent physical properties can be obtained when the number of acid anhydride groups is approximately equal to the number of epoxy groups in the epoxy resin.

The metal-containing curable resin composition of the present invention having an ionic bond as described above has excellent curing properties, and the curing reaction provides a metal-containing curable resin having excellent physical properties, particularly good adhesive properties. . Although the curing reaction proceeds gradually at room temperature depending on the composition, it generally proceeds rapidly at a temperature of 40 to 200°C, preferably 60 to 160°C. It is thought that curing progresses through the following main reaction. That is, first, general formula (1)
The divalent metal salt of lactic acid represented by the formula and the dibasic acid anhydride undergo an addition reaction (half-esterification reaction) to generate an ester bond and a terminal carboxylic acid group. It is thought that the unreacted epoxy groups and anhydride groups alternately repeat addition reactions (esterification reactions) to the terminal carboxylic acid groups to form a polyester. Therefore, it is considered that the resulting cured product necessarily has a three-dimensional structure and methyl carboxylate bonds (ionic bonds). Furthermore, although there is no problem in using a known ester catalyst as a catalyst, in the present invention, the divalent lactic acid represented by the general formula (1), which is one of the components of the metal-containing curable resin composition, is used. It has been discovered that the metal carboxylate group of the metal salt has an excellent catalytic effect on the curing reaction, so the main point is that the curing reaction proceeds smoothly even without the use of a catalyst. It has a major feature of the invention. In addition, when the number of epoxy groups is present in excess of the number of acid anhydride groups, it is considered that some polymerization of the epoxy groups occurs due to the catalytic action of the metal carboxylate groups.

The metal-containing curable resin composition may contain appropriate amounts of fillers, pigments, plasticizer diluents, and the like, if necessary.

As described above, the present invention provides a novel metal-containing cured resin having ionic bonds that can provide a metal-containing cured resin having excellent physical properties, particularly good adhesive properties, in which ionic bonds are introduced in one step without the addition of a catalyst. This metal-containing curable resin composition is expected to have many other uses, including casting resins, adhesives, and paints, and will greatly contribute to the future development of this industry. It is something.

Next, the present invention will be explained in more detail with reference to Examples. Note that all parts in the blending ratio of each component mean parts by weight.

Example 1 A metal-containing curable resin composition was prepared by adding 4.0 parts of magnesium lactate and 29.6 parts of phthalic anhydride to 30.9 parts of diglycidyl ester of hexahydrophthalic acid (epoxy equivalent: 154). This composition is 120
It gels in 12 minutes at ℃. When this composition was cured at 120°C for 1 hour and then at 150°C for 3 hours, an insoluble, infusible, hard and tough metal-containing cured resin was obtained.

Example 2 A metal-containing curable resin composition was prepared by adding 4.4 parts of calcium lactate and 20.0 parts of succinic anhydride to 30.9 parts of diglycidyl ester of hexahydrophthalic acid (epoxy equivalent: 154). This composition gels in 21 minutes at 120°C. When this composition was cured at 120°C for 1 hour and further at 150°C for 3 hours, an insoluble, infusible, hard and tough metal-containing cured resin was obtained.

Example 3 A metal-containing curable resin composition was prepared by adding 4.9 parts of zinc lactate and 19.6 parts of maleic anhydride to 35.2 parts of diglyne cidyl ether of bisphenol A (epoxy equivalent: 176). This composition has a temperature of 14 at 120°C.
Gels in minutes. This composition was heated at 120°C for 1 hour.
Further curing at 150°C for 3 hours yielded an insoluble, infusible, hard and tough metal-containing cured resin.

Example 4 A metal-containing curable resin composition was prepared by adding 4.0 parts of magnesium lactate and 30.8 parts of hexahydrophthalic anhydride to 30.9 parts of diglycidyl ester of hexahydrophthalic acid (epoxy equivalent: 154). This composition gels in 28 minutes at 120°C. When this composition was cured at 120°C for 1 hour and further at 150°C for 3 hours, an insoluble, infusible, hard and tough metal-containing cured resin was obtained.

Comparative Example 1 Diethylene glycol was used instead of the divalent metal salt of lactic acid represented by general formula (1), and 5.3 parts of diethylene glycol and 74.1 parts of phthalic anhydride were added to the diglycidyl ether of bisphenol A (epoxy equivalent: 179). A curable resin composition was prepared by adding 88.1 parts. The gelation time of this composition at 120°C was 5 hours, and even after gelling, hardening did not progress much, and even after being kept at 120°C for 10 hours, only a brittle product was obtained.

From the above results, it is clear that the metal carboxylate group in the metal-containing curable resin composition of the present invention has an excellent catalytic effect on curing. .

Example 5 Magnesium lactate 4.0 parts and maleic anhydride 39.2 parts
A metal-containing curable resin composition was prepared by adding the following parts to 61.8 parts of hexahydrophthalic acid diglycidyl ester (epoxy equivalent: 154). When this composition was sandwiched between two mild steel plates and cured at 150°C for 3 hours, the mild steel plates were bonded together very strongly.
When the adhesive strength was measured by the method of ASTM-D1002-64, a tensile shear adhesive strength of 279 Kg/cm ² was obtained.

Example 6 A metal-containing curable resin composition was prepared by adding 4.4 parts of calcium lactate and 39.2 parts of maleic anhydride to 70.4 parts of diglycidyl ether of bisphenol A (epoxy equivalent: 176). Using this composition, the adhesive strength between mild steel plates and mild steel plates was measured in the same manner as in Example 5, and a tensile shear adhesive strength of 223 kg/cm ² was obtained after curing at 150° C. for 3 hours.

Example 7 A metal-containing curable resin composition was prepared by adding 4.0 parts of magnesium lactate and 30.8 parts of hexahydrophthalic anhydride to 35.2 parts of diglycidyl ether of bisphenol A (epoxy equivalent: 176). Using this composition, the adhesive strength between mild steel plates and mild steel plates was measured in the same manner as in Example 5.
After curing for 3 hours, a tensile shear adhesive strength of 229 kg/cm ² was obtained.

Example 8 A metal-containing curable resin composition was prepared by adding 4.0 parts of magnesium lactate and 61.7 parts of hexahydrophthalic anhydride to 61.8 parts of diglycidiester of hexahydrophthalic acid (epoxy equivalent: 154). Using this composition, a mild steel plate was prepared in the same manner as in Example 5.
When we measured the adhesive strength to mild steel plate, it was 150
A tensile shear bond strength of 234 Kg/cm ² was obtained after curing for 3 hours at °C.

Example 9 A metal-containing curable resin composition was prepared by adding 4.4 parts of calcium lactate and 20.0 parts of succinic anhydride to 35.2 parts of diglycidyl ether of bisphenol A (epoxy equivalent: 176). Using this composition, the adhesive strength between mild steel plates and mild steel plates was measured in the same manner as in Example 5, and a tensile shear adhesive strength of 285 Kg/cm ² was obtained after curing at 150° C. for 3 hours.

Example 10 A metal-containing curable resin composition was prepared by adding 4.0 parts of magnesium lactate and 20.0 parts of succinic anhydride to 30.9 parts of diglycidyl ester of hexahydrophthalic acid (epoxy equivalent: 154). Using this composition, the delayed adhesion strength between mild steel plates and mild steel plates was measured in the same manner as in Example 5, and a tensile shear adhesive strength of 287 Kg/cm ² was obtained after curing at 150° C. for 3 hours.

Comparative Example 2 Using a magnesium salt of stearic acid instead of the divalent metal salt of lactic acid represented by the general formula (1), 5.9 parts of the magnesium salt of stearic acid and 39.2 parts of maleic anhydride were mixed with hexahydrophthalic acid. A metal-containing curable resin composition was prepared by adding it to 61.8 parts of diglycidyl ester (epoxy equivalent: 154). Using this composition, the adhesive strength between mild steel plates and mild steel plates was measured in the same manner as in Example 5.
After curing for 3 hours, a tensile shear adhesive strength of 142 kg/cm ² was obtained.

Comparative Example 3 Diethylene glycol was used instead of the divalent metal salt of lactic acid represented by the general formula (1), and 4.2 parts of diethylene glycol, 39.2 parts of maleic anhydride, and 0.6 parts of N,N dimethylbenzylamine as a catalyst were mixed into hexahydrophthalate. A curable resin composition was prepared by adding 61.8 parts of acid diglycidyl ester (epoxy equivalent: 154). Using this composition, the adhesive strength between mild steel plates and mild steel plates was measured in the same manner as in Example 5, and it was found that after curing at 150°C for 3 hours, the adhesive strength was 190.
A tensile shear bond strength of Kg/cm ² was obtained.

Comparative Example 4 19.6 parts of maleic anhydride and 0.2 parts of N,N dimethylbenzylamine as a catalyst were mixed into bisphenol A.
diglycidyl ether (epoxy equivalent weight 176)
A curable resin composition was prepared by adding 35.3 parts.
Using this composition, the adhesive strength between mild steel plates and mild steel plates was measured in the same manner as in Example 5.
A tensile shear adhesive strength of 158 Kg/cm ² was obtained.

Comparative Example 5 A mild steel plate-mild steel plate was prepared in the same manner as in Example 5 by mixing equal amounts of the main ingredient and curing agent of a commercially available epoxy resin adhesive in which the main ingredient is diglycidyl ether of bisphenol A and the curing agent is polyamide. When we measured the adhesive strength for 1 hour of curing at 80℃
A tensile shear adhesive strength of 163 Kg/cm ² was obtained.

Comparative Example 6 9.9 parts of diaminodiphenylmethane was mixed with diglycidyl ether of bisphenol A (epoxy equivalent
190) Using the curable resin composition obtained by adding 38.0 parts, the adhesive strength between mild steel plates and mild steel plates was measured in the same manner as in Example 5. A tensile shear adhesive strength of 138 Kg/cm ² was obtained after curing for hours.

It is clear from the above examples that the metal-containing curable resin composition of the present invention provides a cured product having excellent physical properties, particularly good adhesiveness.

Claims (1)

[Claims] 1 General formula (1) (However, M represents a divalent metal) An ionic bond characterized by adding a divalent metal salt of lactic acid represented by the formula and a dibasic acid anhydride to an epoxy resin at a molar ratio of 1:6 to 40. A metal-containing curable resin composition.