JPS5950247B2 - Curable resin composition - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a curable resin composition, and particularly to a curable resin composition that has improved temperature dependence of electrical resistance, adhesion of a coating film, heat resistance, and shrinkage during curing. Regarding.

Epoxy resins, unsaturated polyester resins, polybutadiene resins, and the like are known as resins with excellent electrical insulation properties that are generally used for laminated products, molded products, paints, and various coatings.

By the way, in the case of epoxy resin, although it has excellent heat resistance, it has the disadvantages of short pot life and poor workability.

In addition, unsaturated polyester resins have the advantage of being cheap and easily available, and can be diluted with polymerizable monomers such as styrene to lower their viscosity, but on the other hand, they have insufficient heat resistance and electrical insulation properties. , especially the shrinkage rate during heat curing is large,
It has the disadvantage of causing cracks and deterioration of electrical insulation properties.

On the other hand, polybutadiene resin has excellent electrical insulation properties, but has poor adhesion as a coating film and poor crack resistance as a molded product. As a means to solve these disadvantages, for example, for epoxy, attempts have been made to make it into a radical reaction type by acrylation, and for unsaturated polyester resin, so-called modification has been attempted, for example, by adding petroleum tar resin or xylene formaldehyde resin. However, none of them have reached a level of practical satisfaction.

Furthermore, Japanese Patent Publication No. 45-14798 describes synchropentanenyl α,β unsaturated fang [made by reacting a basic acid monoester and a glycidyl ether compound, air curable with low shrinkage rate, heat resistance, mechanical properties, A polyester resin composition with excellent electrical properties is described.

However, this polyester resin composition has problems in that it is expensive to manufacture and generates odor during the synthesis process.

That is, this starting material, synchropentadiene, is usually produced by dimerizing cyclopentadiene, but its yield is low (about 10%), and the cost of raw materials is high, and its boiling point is relatively low at 170°C. When reacting with maleic anhydride, a part of it evaporates and gives off an odor.
The problem was that it created a poor working environment.

The present inventor carried out intensive research in order to eliminate such conventional drawbacks, and found that cyclopentadiene trimer or higher polymers and cyclopentadiene and 1,3 Addition polymers with pentadiene are inexpensive, and because they have a large molecular weight, no odor is generated during synthesis.Moreover, this polymer is reacted with maleic anhydride and water to form an unsaturated carboxylic acid, which is then reacted with epoxide. By mixing with a monomer having α,β unsaturated double bonds in the molecule, the temperature dependence of electrical resistance value, the adhesion of the coating film, the heat resistance, and the shrinkage properties during curing are improved. It has been found that a resin composition can be obtained.

The present invention was made based on such knowledge, and (A)
K) Cyclopentadiene and 1,3-
A monovalent unsaturated carboxylic acid obtained by reacting an addition polymer with pentadiene with maleic anhydride and water at a temperature of 140°C or less, and a polymer produced by the reaction with (→ epoxide), (13) α , a monomer having a β-unsaturated double bond in the molecule and an O polymerization initiator as essential components, and contains the aforementioned prisoner component and (self) component in a weight ratio of 90/10 to 30/70. An object of the present invention is to provide a curable resin composition characterized by the following.

In the present invention, the monovalent unsaturated carboxylic acid used in the production of the polymer constituting the prisoner component is produced in the first step, which is an addition reaction between cyclopentadiene and 1,3-pentadiene, and in the first step. It is obtained through a second step, which is the reaction of the product of the step with maleic anhydride and water.

<First step> Note that such addition polymers include, for example, QN-0301
(or RX-0330-WAX) from Nippon Zeon Co., Ltd.

Step 2> (In the formula, n is the number 2 or 3) In the second step shown in the above formula, the reaction composition ratio of the addition polymer and maleic anhydride is approximately equimolar, and the amount of water added is anhydrous. It is preferable to use a slight excess of maleic acid.

However, if the reaction temperature exceeds 140°C, a part of the addition polymer, which is one of the reaction components, tends to distill out of the reaction system, making it impossible to obtain the desired monovalent unsaturated carboxylic acid. It is necessary to choose a temperature below 140°C.

In the first step, a small amount of products with n=1 and 5 are produced as by-products, but it is not necessary to separate them.

In the present invention, the polymer constituting the (self) component is selected from the above-mentioned monovalent unsaturated carboxylic acid and epoxide at an equivalent ratio of carboxyl group to epoxy group of 1 or close to 1 at a temperature of, for example, 80 to 120°C. It can be easily obtained by reacting in the presence of a known polymerization inhibitor.

The epoxide used here is a compound having at least one, preferably two or more, epoxy groups per molecule,
For example, glycidyl ethers of polyhydric alcohols or polyphenols, epoxidized fatty acids, epoxidized drying oils,
Examples include epoxidized diolefins, epoxidized diunsaturated acid esters, and oligomers thereof.

In the present invention, examples of monomers having an α,β unsaturated double bond in the molecule that constitute the (auto) component include styrene,
Examples include α-methylstyrene, chlorostyrene, vinyltoluene, vinylnaphthalene, esters of acrylic acid or methacrylic acid, vinyl esters of acetic acid or propionic acid, esters of maleic acid, fumaric acid, and itaconic acid.

However, these may be used alone or in a mixed system of two or more, but the composition ratio (weight ratio) of the (self) component and the (self) component is (A)/(B) = 90/10 ~ 30/70
You need to choose. That is, (A)/(self) is 90/10
If it exceeds 30/70, the composition will have a high viscosity and its workability will be impaired, and if it is less than 30/70, it will lack toughness when cured. Preferably (A)/(l=80/
It is 20-40/60.

In the present invention, the resin component may be composed only of the above-mentioned parent component and (self) component, but may also be appropriately added and blended with, for example, oligomer ester acrylate, epoxy ester, polybutadiene, unsaturated polyester resin, etc.

In the present invention, as the polymerization initiator constituting the O component, a photocuring type and a thermosetting type are used.

First, if photocuring is desired, photosensitization of benzoin, benzoin ethyl ether, benzoin isopropyl ether, benzoin phenyl ether, benzoin alkyl ethers, benzointhioethers, benzophenone, acetophenone, 2-ethylanthraquinone, decyl chloride, etc. agent can be used.

However, these may be used alone or in a mixed system of two or more, and the amount used is equivalent to 0.5 to 10% by weight based on the total curable resin content, including the resin content added as necessary. Preferably, the amount is equivalent to 1 to 5% by weight.

On the other hand, when heat curing is desired, for example, acyl peroxides such as benzoyl peroxide and acetyl peroxide, hydroperoxides such as tertiary butyl peroxide and kyumene hydroperoxide, ketone peroxides such as methyl ethyl ketone peroxide and cyclohexanone peroxide, Ditertiary butyl peroxide and the like are used.

These radical polymerization initiators may be used alone or in a mixture of two or more, and in that case, metal naphthenates or octenoates of iron, cobalt, lead, manganese, nickel, tin, zinc, etc. can also be used in combination as a curing accelerator.

However, the amount of the thermosetting polymerization initiator (radical initiator) used is about 0.5 to 5% by weight (preferably 1 to 3% by weight) based on the total polymerizable resin content such as the captive component and the (self) component. That's fine. Further, the amount of the curing accelerator that can be used in combination is about 0.01 to 1% by weight, preferably about 0.05 to 0.4% by weight based on the total polymerizable resin content.

In the present invention, the above-mentioned polymerization initiator may be a combination of a photocuring type and a thermosetting type, or may be filled with aluminum hydroxide, calcium carbonate, silica, alumina, glass fiber, organic fiber, etc. There is no problem in adding appropriate additional ingredients such as additives, reinforcing agents, pigments, and dyes. The curable resin composition according to the present invention as described above has, for example, 100 to 15
While it is easily cured by heating to about 0°C or by irradiation with ultraviolet rays, it is difficult to cause gelation when stored at room temperature, and has good fluidity during casting, so it has good workability.

Furthermore, since the shrinkage rate during heat curing is small, even when an insulating structure is formed by casting, for example, no peeling or cracking occurs and the material exhibits excellent electrical insulation function.

Moreover, the hardened insulating structure has little change in insulating properties due to changes in temperature, etc., and therefore can always maintain and exhibit excellent insulating function.

Furthermore, when formed into a coating film, it shows good adhesion and does not cause any cracks.

Thus, the resin composition according to the present invention has good heat resistance and exhibits excellent functions in applications such as laminated products, molding products, and various coating agents.

Next, examples of the present invention will be described.

Examples 1 to 3 First, three types of polymers corresponding to component (4) in the present invention were synthesized as follows.

196 g of maleic anhydride was placed in 21 four-bottle flasks equipped with a condenser, nitrogen inlet, thermometer, and stirrer.
, water 509, addition polymer of cyclopentadiene and 1,3-pentadiene QN-0301-WAX'' (trade name, Nippon Zeon Co., Ltd.) 5509, and hydroquinone 0.0
49 was charged and reacted at 140° C. for 3 hours under a nitrogen stream, followed by dehydration under reduced pressure to obtain a monovalent unsaturated carboxylic acid.

Next, epoxide Epicote 828″ (trade name, Ciel Chemical Co., Ltd.) 3809 and penzyldimethylamine 29
was added and reacted at 100°C for 6 hours to form a resin with an acid value of 11 (
Polymer 1) was obtained.

Also, in the above, Epicote 828 is used as the epoxide.
Instead of ``(product name) 3809, use Epicote 836'' (
A resin (polymer) having an acid value of 9 was obtained by reacting under the same conditions except that 7109 (trade name, Ciel Kagaku Co., Ltd.) was used.

Furthermore, in the above reaction, Epicote 828'' (trade name) 1909 and Epicote 100 were used as epoxides.
1'' (trade name: Ciel Chemical Co., Ltd.) 4819 and benzyldimethylamine 39 were used, but the reaction was carried out under the same conditions to give an acid value of 1.
0 resin (polymer 1) was obtained.

Polymers (1), 01) and Il respectively obtained as above
), unsaturated polyester resin with acid value 20, epoxy acrylate lipoxy El3OO'' (trade name, Showa Kobunshi Co., Ltd.), oligoester acrylate Aronix 61
00'' (trade name, Takuyasei Co., Ltd.), 2-hydroxyethyl methacrylate, trimethylolpropane triacrylate, styrene, cobalt naphthenate (6% xylene solution), dibutylperoxy 3,3,5-trimethylcyclohexane, tertiary The composition ratios of butyl benzoate and benzoin isopropyl ether shown in Table 1 (
(parts by weight) to prepare six types of curable resin compositions including a comparative example.

The unsaturated polyester resin used here was made using the same reaction apparatus as above, and 1969% of maleic anhydride, 2019% of propylene glycol, 4449% of phthalic anhydride, and 0.049% of hydroquinone were prepared, and the mixture was heated to 150 to 20% under a nitrogen atmosphere.
It was obtained by carrying out a reflux reaction at 10°C, and when the acid value of the product reached 20, dehydration was carried out under reduced pressure.

The viscosity (
25℃) and applied to a tin plate, copper plate, or phenol laminate, and hardened by heating at 110℃ for 1 hour, or using a 2Kw mercury lamp x 0.5m/-, irradiation distance 10m.
Hardening due to UV irradiation in wt. Table 2 shows the results of measurements of curability, coating hardness, coating adhesion, coating volume insulation resistance, etc. in the case of chemical treatment.

Adhesion was measured by making straight cuts of 2n width each in the length and width of the cured coating, making 100 goblets, pasting adhesive cellophane tape on top of them, and measuring the number of goblets that remained in a plate shape when the tape was peeled off. Also, the volume insulation resistance is JISC
This is a measured value according to 2lO5.

Examples 5 to 7 Polymer I (Example 5), Polymer (Example 6), and Polymer I (Example 7) used in Examples 1 to 4. and 60 parts by weight of the unsaturated polyester resin used in Comparative Example 1 (Comparative Example 3), 40 parts by weight of styrene, 0.5 parts by weight of cobalt naphthenate, and 1 part by weight of methyl ethyl ketone peroxide were added and blended. Four types of resin compositions were prepared.

Next, each of these resin compositions was injected into a mold having a plate-like cavity with a thickness of 2 mwL, and was allowed to stand at 25° C. for 2 hours and then at 100° C. for 2 hours to harden.

Table 3 shows the volume insulation resistance values of each of the obtained resin plates, which were measured using the JIS K691 method.

Claims (1)

[Scope of Claims] 1 (A) (B) Cyclopentadiene represented by the general formula ▲ There are mathematical formulas, chemical formulas, tables, etc. ▼ or ▲ There are mathematical formulas, chemical formulas, tables, etc. ▼ (n is an integer of 2 or 3) and 1,3-pentadiene, maleic anhydride, and water at a temperature below 140°C. Combine, (B
) A monomer having α,β unsaturated double bonds in the molecule and (C) a polymerization initiator are essential components, and the above (A) component and (B
) components in a weight ratio of 90/10 to 30/70. 2 The ratio of component (A) to component (B) is 80/20 to 40
2. The curable resin composition according to claim 1, which has a hardness of /60. 3. The curable resin composition according to claim 1, wherein the component (B), a monomer having α,β unsaturated bonds in its molecule, is styrene. 4. The curable resin composition according to claim 1 or 2, wherein the polymerization initiator as component (C) is a radical polymerization initiator. 5. The curable resin composition according to claim 1 or 2, wherein the polymerization initiator as component (C) is a photosensitizer.