JPH0725864B2 - Epoxy resin - Google Patents

Description

TECHNICAL FIELD OF THE INVENTION The present invention relates to an epoxy resin having excellent heat resistance, water resistance and weather resistance, and having improved water absorption by containing a functional group in a molecule at a constant ratio. It is a thing.

(Prior Art) Generally, the most widely used epoxy resin is an EP bis type epoxy resin produced by a reaction of bisphenol A and epichlorohydrin.

This resin has a wide range of products from liquid to solid,
It is so reactive that it can be cured with polyamines at room temperature.

However, even though the cured product has excellent water resistance and is strong, it has the drawbacks of poor weather resistance and electrical properties and a low heat distortion temperature.

Novolac phenol and novolac cresol type epoxy resins are used as encapsulating resins for ICs, LSIs, VLSIs, etc., but the problem is that chlorine contained in the resin deteriorates the electrical characteristics of electronic components. Has become.

On the other hand, the alicyclic epoxy resin is an epoxy resin which does not contain chlorine and has excellent electric characteristics and heat resistance.

However, currently manufactured cycloaliphatic epoxy resins are
Due to its low reactivity, curing methods are also limited.

(Problems to be Solved by the Invention) The epoxy resin proposed in JP-A-60-161973 has excellent water resistance, heat resistance and weather resistance, It has one or more skeletons and has higher reactivity than conventional alicyclic epoxy resins, and can cure acid anhydrides, phenols and amines.

However, since this epoxy resin has a relatively high water absorption of a cured product, it has not been sufficient for electrical fields such as semiconductor encapsulating materials.

Therefore, the present inventors have found that the water absorption rate is improved by introducing a vinylcyclohexane skeleton into the molecule of an epoxy resin having an oxycyclohexane skeleton, and arrived at the present invention.

(Structure of the Invention) That is, the present invention relates to "general formula (I) << R ¹ is a residue of an organic compound having ¹ active hydrogen, n1, n2
... nl is an integer of 1 to 100 and the sum thereof is 1 to 100; l represents an integer of 1 to 100; A is an oxycyclohexane skeleton having a substituent and is represented by the following formula; R ² is any one of H, an alkyl group, an alkylcarbonyl group, and an arylcarbonyl group, Containing at least one in the resin represented by the formula (I) >> in the epoxy resin represented by Is an average of 1.0 to 4.0 "
Is.

Next, the present invention will be described in detail.

The epoxy resin having the partial structures (I) and (II) of the present invention in a fixed ratio is obtained by partially epoxidizing the vinyl group of the polyether compound having the basic structure represented by (II).

The polyether compound having a basic structure represented by (II) is a compound having active hydrogen and 4-vinylcyclohexene 1-oxide. And other compounds having one epoxy group Can be obtained by reacting in the presence of a catalyst.

In this reaction, the molecular weight can be variously adjusted by changing the reaction ratio of the compound having active hydrogen and the compound having 4-vinylcyclohexene 1-oxide and one epoxy group.

It is also desirable to react 4-vinylcyclohexene 1-oxide and a compound having one epoxy group together in a ratio of 2 to 100 per molecule of the compound having active hydrogen.

When the sum is 100 or more, it becomes a solid with a high melting point and cannot be practically used.

Compounds having 4-vinylcyclohexene 1-oxide and one epoxy group are 1 to 100% of 4-vinylcyclohexene 1-oxide and 99% of compounds having one epoxy group.
React at ~ 0%.

When the content of 4-vinylcyclohexene 1-oxide is 1% or less, the characteristic of the cyclohexane skeleton does not appear.

Examples of the compound having active hydrogen include alcohols, phenols, carboxylic acids, amines and thiols.

Examples of the catalyst used in the reaction include amines such as methylamine, ethylamine, propylamine and piperazine, organic bases such as pyridine and imidazole, quaternary ammonium salts such as tetrabutylammonium bromide, formic acid, acetic acid and propionic acid. Organic acids, inorganic acids such as sulfuric acid and hydrochloric acid, alcoholates of alkali metals such as sodium methylate, alkalis such as KOH and NaOH, BF3, ZnCl
2, Lewis acids such as AlCl3 and SnCl4 or complexes thereof, and organometallic compounds such as triethylaluminum and diethylzinc.

The amount of catalyst varies depending on the type, but is 0 for the starting material.
It can be used in the range of 01 to 10%, preferably 0.1 to 5%.

The reaction temperature is -20 to 200 ° C, preferably 0 to 120 ° C. The reaction can also be carried out using a solvent.

The epoxy resin of the present invention can be obtained by epoxidizing the thus obtained polyether compound having a vinyl group side chain with an oxidizing agent such as peracids and hydroperoxides.

As the peracids, formic acid, peracetic acid, perbenzoic acid, trifluoroperacetic acid and the like can be used.

Of these, peracetic acid is a preferable epoxidizing agent because it is industrially available at low cost and has high stability.

As the hydroperoxides, hydrogen peroxide, tertiary butyl hydroperoxide, cumene peroxide and the like can be used.

A catalyst may be used in the epoxidation, if necessary.

For example, in the case of peracid, an alkali such as sodium carbonate or an acid such as sulfuric acid can be used as a catalyst.

In the case of hydroperoxide, a catalytic effect can be obtained by using a mixture of tungstic acid and caustic soda with hydrogen peroxide, an organic acid with hydrogen peroxide, or molybdenum hexacarbonyl with tert-butyl hydroperoxide. .

The epoxidation reaction is carried out by adjusting the presence or absence of a solvent and the reaction temperature according to the physical properties of the equipment and raw materials.

The reaction temperature range that can be used depends on the reactivity of the epoxidizing agent used.

Peracetic acid, which is a preferred epoxidizing agent, is 0-
70 ° C is preferred.

The reaction is slow below 0 ° C, and the decomposition of peracetic acid occurs at 70 ° C.

In the tertiary butyl hydroperoxide / molybdenum dioxide diacetylacetonate system, which is an example of hydroperoxide, 20 ° C. to 150 ° C. is preferable for the same reason.

The solvent can be used for the purpose of reducing the viscosity of the raw material and stabilizing it by diluting the epoxidizing agent.

In the case of peracetic acid, aromatic compounds, ether compounds,
An ester compound, a ketone compound, etc. can be used as a solvent.

The following formula Ratio of the number of functional groups represented by 50 to 80% of the vinyl groups are epoxidized so that the average is 1.0 to 4.0.

If the ratio is less than 1.0, the crosslink density of the cured product is low, and if it exceeds 4.0, the water absorption is high.

This epoxy compound is synthesized by adjusting the charged molar ratio of the epoxidizing agent to the unsaturated bond.

In the case of peracetic acid, the charge molar ratio is preferably 0.5-0.8.

The target compound can be taken out from the reaction crude liquid by ordinary chemical engineering means such as concentration.

(Effects of the Invention) A cured product of the epoxy compound of the present invention thus obtained and a phenol novolak resin or other curing agent is excellent in heat resistance, water resistance, weather resistance, and excellent in water absorption. It can be used as an LSI sealing material.

Also, it has an advantage that performance can be adapted by freely adjusting the degree of polymerization and the like as a substitute for the conventional use of epoxide such as coil impregnation.

Furthermore, it can be applied to a wide range of applications such as LED and semiconductor encapsulation materials and paints.

Hereinafter, the present invention will be described in more detail with reference to examples.

Synthesis Example 1 134 g (1 mol) of trimethylolpropane and 1860 g (15 mol) of 4-vinylcyclohexene-1-oxide were mixed, and 400 g of a 10% ethyl acetate solution of BF3-etherate was mixed with 50 g of 50%.
It was added dropwise at 4 ° C over 4 hours.

Ethyl acetate was added to the obtained reaction crude liquid and the mixture was washed with water, and then the ethyl acetate layer was concentrated to give an unsaturated compound having the structure shown below.
1990g was obtained.

(N1 + n2 + n3 = average 15) However, A is represented by the following equation.

500 g of this compound was dissolved in 250 g of ethyl acetate and charged into a reactor, and 172 g of peracetic acid (molar ratio to vinyl group: 0.6) was added dropwise as an ethyl acetate solution at 50 ° C. over 4 hours.

After completion of dropping, the mixture was further aged at 50 ° C. for 2 hours.

After removing acetic acid, ethyl acetate, and peracetic acid, the residue was dissolved in ethyl acetate again, washed with distilled water, and the ethyl acetate layer was concentrated to obtain a compound having the following structure.

(N1 + n2 + n3 = average 15) However, B is represented by the following equation.

Oxylan oxygen concentration 6.20%, iodine value 72.
The saponification value was 20.0.

Comparative synthesis example Charge 286 g of peracetic acid (molar ratio to vinyl group 1.0)
The same procedure as in Example was carried out except that the above was changed to obtain an epoxy compound having the following structural formula.

(N1 + n2 + n3 = 15 on average) The composition of B is as follows.

Application Example The epoxy compounds obtained in Examples and Comparative Synthesis Examples, cresol novolac resin (PSF-4300 manufactured by Gunei Chemical Co., Ltd.), and triphenylphosphine were blended as shown in Table 1 and melt kneaded.
After cooling and pulverizing, an epoxy resin composition was obtained.

Further, it was pressed at 70 ° C. 100 kg / cm ² and heated to 170 ° C. over 30 minutes to pre-cure, and after curing at 170 ° C. for 4 hours, water absorption was measured.

The results are shown in Table 1.

As described above, it is clear that the epoxy resin obtained by the present invention has improved water absorption.

Claims (1)

[Claims] 1. A general formula (I) << R ¹ is a residue of an organic compound having ¹ active hydrogen, n1, n2
... nl is an integer of 1 to 100 and the sum thereof is 1 to 100; l represents an integer of 1 to 100; A is an oxycyclohexane skeleton having a substituent and is represented by the following formula; R ² is any one of H, an alkyl group, an alkylcarbonyl group, and an arylcarbonyl group, Containing at least one in the resin represented by the formula (I) >> in the epoxy resin represented by Is an average of 1.0 to 4.0, an epoxy resin.