JPS5847422B2 - thermosetting resin material - Google Patents

Description

Detailed Description of the Invention The present invention relates to a thermosetting resin material that provides a cured product with excellent heat resistance and mechanical properties, and more specifically to a polymer obtained by reacting a polyfunctional epoxy resin with a polyfunctional cyanate compound. The present invention relates to a thermosetting resin material containing an oxazoline ring and a triazino ring as repeating units.

In recent years, with the increasing performance of electrical equipment, there has been an increasing need for thermosetting resins with excellent heat resistance and mechanical properties.

Epoxy resins, silicone resins, polyimide resins, and the like are well-known as conventional thermosetting resins with excellent heat resistance.

However, when the epoxy resin is exposed to high temperatures of 180° C. or higher for a long time, it cannot maintain sufficient heat resistance.

Residual polyimide resin exhibits excellent heat resistance, but this resin is difficult to use without solvents and is inconvenient to use, and furthermore, the cured product is hard but brittle. There is.

The silicone resin and polyimide resin used in the casing are extremely expensive compared to epoxy resins, etc.

As described above, each of the conventional heat-resistant resins has its own drawbacks, but the inventors of the present invention have completed the present invention as a result of intensive research to improve these drawbacks.

An object of the present invention is to provide a thermosetting resin material with excellent heat resistance and mechanical properties.

This invention relates to a novel polymer containing one or more triazine rings and an oxazoline ring connecting them as repeating units, as shown in the following formula (1) obtained by the reaction of a polyfunctional epoxy resin and a polyfunctional cyanate compound. The present invention provides a thermosetting resin material comprising:

(In the formula, R is a residue of a polyfunctional epoxy resin, R' is a residue of a polyfunctional cyanate compound, and n and m each represent an integer of 1 or more.

) The thermosetting resin material of the present invention (hereinafter simply referred to as polymer) is characterized by containing an oxazoline ring and a triazine ring in its molecular chain.

Polymers containing such a heterocycle are generally said to have excellent heat resistance, and in fact, the polymer of the present invention also has very excellent heat resistance.

Furthermore, the polymer of the present invention also has very excellent mechanical properties, which seems to be the result of appropriate combinations and repetitions of these heterocycles.

The polymer of the present invention can be easily obtained by reacting a polyfunctional cyanate compound and a polyfunctional epoxy resin in the presence or absence of a solvent.

The polyfunctional cyanate compound used in the present invention is an organic group in which (R/ is a cyanate residue, an aromatic group, and two or more aromatic groups are bonded via a bridge).

n represents an integer of 2 or more. ).

Typical polyfunctional cyanate compounds suitably used in the present invention are illustrated below.

These polyfunctional cyanate compounds can be easily obtained by reacting corresponding phenols with halogen cyanide.

(References Angew. Chem. t79, (1
967) 219. ) As these polyfunctional cyanate compounds, cyanate trimers obtained by reacting acid and base catalysts with (1) functional or polyfunctional cyanate compounds can also be used.

Among the above-mentioned polyfunctional cyanate compounds, bisphenol A dicyanate and novolac polycyanate are particularly good in terms of reactivity and properties of cured products.

In addition, examples of epoxy resins used in the present invention include 2,2'-bis(P-hydroxyphenyl)furopane, 2,2'-bis(4-hydroxy-3,5-diprophenyl)propane, 1 , 1,2,2, monotetrakis(P-hydroxyphenyl)ethane, 4,4-dihydroxydiphenyl, resorcinol, catechol, hydroquinone, and other aromatic phenol glycidyl ethers, as well as phenol novolak, cresol novolak, and other glycidyl ethers. , vinylcyclohexene diepoxide, limonene diepoxide, dicyclopentadiene diepoxide, (3',4'-epoxycyclohexylmethyl)-3,4-epoxycyclohexanecarboxylate, (3',4'-epoxy 6') -methylcyclohexylmethyl)-3,4-epoxy-6-methylcyclohexanecarpoxylate, 3-(3',4'-epoxycyclohexyl)-2,4-dioxaspi(5
．． 5) Cycloaliphatic epoxy resins such as -8,9-epoxyundecane and 3-(glycidyloxyethoxyethyl)-2,4-dioxaspiro(5,5)-8,9-epoxyundecane, and triglycidyl isocyanurate , N of 5,5-dimethylhydantoin, N'
-diglycidyl derivatives, isoheterocyclic epochene resins, and the like.

Any of these can be used alone or in combination, but bisphenol-based or novolak-based ones are particularly preferred in terms of their properties.

In the present invention, the blending ratio of the polyfunctional cyanate compound and the polyfunctional epoxy resin is not particularly limited, but it is preferable to blend the polyfunctional cyanate in an amount of 1 equivalent or more, preferably 1 to 3 equivalents, per equivalent of the polyfunctional epoxy resin. good.

The reason why the polyfunctional cyanate compound is added in excess to the polyfunctional epoxy resin is that the polyfunctional cyanate compound is consumed by self-conversion in addition to the reaction with the polyfunctional epoxy resin.

The polymer (cured product) according to the present invention is obtained by preparing the mixture obtained as described above preferably at 100 to 120° C. at 0.5° C. initially.
Heat for 5-5 hours, then heat at 150-180℃ for 1-40
Obtained by heating for hours.

1. Post-curing at 200° C. or higher is also carried out if necessary.

By heating in two stages, after the initial heating, trimerization of the polyfunctional cyanate compound mainly proceeds to form a triazine ring.

This is expressed in equation (3). (R/ represents a pacyanate residue.

) The epoxy group and the cyanate group react with each other by heating to raise the temperature, and the oxazoline ring is formed to form the final polymer (cured product).

Expressed in

This is represented by the formula (4) where c R/ represents a cyanate residue and R represents an epoxy residue.

) When reacting the mixture of the cyanate compound and the epoxy resin, it can be used not only in a solvent-free form, but also in a solvent form, and a catalyst is not necessarily required.

Furthermore, it can be used as a laminate, prepreg, etc. by applying it to a base material such as glass or aluminum.

It may also be used in the form of a solid epoxy resin and a powder.

Furthermore, it is possible to use various fillers, diluents, modifiers, pigments, extenders, softeners, etc., as appropriate, and the resulting polymer has particularly high heat resistance. It is extremely useful for materials that require mechanical properties, such as electrical insulating materials.

Next, the present invention will be explained in more detail with reference to Examples and Comparative Examples.

l, - Measurement of bending strength in the examples is based on JI/S standard K-6.
This was done based on 911.

Example 1 2.2-bis(4-cyanatophenyl)propane 14
0 parts by weight, 100 parts by weight of diglycidyl ether of bisphenol A with an epoxy equivalent of 190 is added to 60 to 80 parts by weight.
Mix at °C to obtain a homogeneous solution.

When the IR absorption spectrum of this product was heated at 110°C for 1 hour, it was found that although the absorption of the epoxy group observed in 910cIrL-1 was slightly decreased, the absorption of the cyanate group observed in 2300crrL-1 was has decreased significantly, and instead is 1575 crrL.
' and 1380 cm', absorptions that appear to be due to the triazine ring appear.

From this, it is thought that at this stage, a formal reaction of the triazide ring formation reaction occurs mainly due to self-trimerization of the polyfunctional cyanate compound.

Further, when this product was heated at 180° C. for 5 hours and its IR and absorption spectra were measured, the absorption at 910m' due to the epoxy group completely disappeared, and absorption due to the oxazoline ring appeared around 1670cIrL-7.

From this, it is thought that at this stage, the reaction to form an oxazoline ring is mainly occurring due to the reaction between the epoxy group and the cyanate group.

In order to form a cured product containing a triazine ring and an oxazoline ring in the polymer structure, which is the gist of the present invention, it is very important to perform heating in two stages.

Example 2 The properties of the heat-cured sample in Example 1 were as follows.

Bending strength (room temperature) 16:00/Station 2//
(220℃, after 20 days) 1 4. 5K
9/m” heating loss ( ) 6.0%
〃 Thermal softening temperature 220°C Example 3 2,2-bis(4-cyanatophenyl)propane 14
175 parts by weight of a novolak epoxy resin having an epoxy equivalent of 175 were mixed with 0 parts by weight at 60 to 80 DEG C. to obtain a uniform solution.

This was heated under the same conditions as in Example 1, and the properties of the cured product were as follows.

Bending strength (room temperature) 12.5 lucid/Otori 2〃
(220°G, 20 days later) 1 0. oK;
//m2 heating loss ()8.

6% Thermal softening temperature 180°C Example 4 2,2-bis(4-cyanatophenyl)propane 14
60 parts by weight of a novolak epoxy resin having an epoxy equivalent of 175 were mixed at 60 to 80°C to obtain a uniform solution.

This was heated under the same conditions as in Example 1, and the properties of the cured product were as follows.

Bending strength (room temperature) 1 7. 5 K9/
ytm2// (220℃, 20 days later) 15
．． 3Kl9/7ia2 heating loss ( )
4.8% Thermal softening temperature 240°C Example 5 For 100 parts by weight of a cyanate compound obtained from novolac type phenol having an average molecular weight of about 60°C, (3
/ , 4/monoepoxycyclohexylmethyl)-3.
50 parts by weight of 4-epoxycyclohexanecarboxylate (trade name Chitsonotsukusu 221), 60 to 80°C
to obtain a homogeneous solution.

This was heated under the same conditions as in Example 1, and the properties of the cured product were as follows.

Bending strength (room temperature) 13.8 hours 71Ig
12tt (220℃, 20 days later) 1 2
．． 6 o'clock/m2 heating loss ( ) 5.
0%〃 Thermal softening temperature 250°C Example 6 Poupane 14 of 2,2-bis(4-cyanatophenyl)
0 parts by weight, 100 parts by weight of glycidyl ether of bisphenol A having an epoxy equivalent of 190 was simultaneously dissolved in 60 parts by weight of methyl ethyl ketone and 200 parts by weight of toluene.

This solution was applied with a brush to a layered glass woven fabric and laminated mica foil, air-dried for 30 minutes, and then dried in an oven at 100° C. for 20 minutes to form a prepreg.

Layer several sheets of this prepreg and heat at 120℃ for 1 hour.
A laminate was formed by pressing at 0'C for 3 hours at a pressure of 50 hours/d.

This material was post-cured at 200° C. for 5 hours, and the bending strength at room temperature was 40 hours/N2.

Example 7 2,2-bis(4-cyanatophenyl)propane 14
0 parts by weight, 100 parts by weight of a bisphenol A-based epoxy tree having an epoxy equivalent of about 900 was dissolved in flubento naphtha.

This material was applied to a silicon steel plate and heated at 200 to 300°C for 5 minutes to obtain a uniform cutlet-colored and tough coating film.

Comparative Example 1 Novolak epoxy resin with an epoxy equivalent of 175
00 parts by weight were used, and ss parts by weight of methylendomethylenetetrahydrophthalic anhydride and 0.5 parts by weight of pendylmethylamine were added, mixed uniformly, heated at 150°C for 8 hours, and then heated at 170°C for 6 hours. A cured product was obtained.

This product has a bending strength of 8. 2K9/ytm2,
2 2 The weight loss rate after heat aging at 0℃ for 20 days is 10%.
Met.

When the R absorption spectra of the cured resin products of Examples 2 to 6 described above were measured, the presence of triazine rings and oxazoline rings was observed in all of them.

As described above, the thermosetting resin material of the present invention contains a triazine ring and an oxazoline ring in its polymer, and therefore, the cured product has excellent heat resistance and mechanical properties, and is extremely useful industrially.

Claims (1)

[Claims] 1 Represented by the general formula (in the formula, R is a residue of a polyfunctional epoxy resin, R' is a residue of a polyfunctional cyanate compound, and n.b and m each represent an integer of 1 or more). A thermosetting resin material characterized by containing an oxazoline ring and a triazine ring in repeating units. 2. The thermosetting resin material according to claim 1, wherein the polyfunctional epoxy resin is a bifunctional epoxy resin. 3. The thermosetting resin material according to claim 2, wherein the bifunctional epoxy resin is bisphenol A-based diglycidyl ether. 4. The thermosetting resin material according to claim 1, wherein the polyfunctional epoxy resin is a novolac polyglycidyl ether. 5. The thermosetting resin material according to any one of claims 1 to 4, wherein the polyfunctional cyanate compound is a difunctional cyanate compound. 6. Claim 5, wherein the difunctional cyanate compound is a bisphenol A-based dicyanate.
Thermosetting resin material described in Section 1. 7. The thermosetting resin material according to any one of claims 1 to 4, wherein the polyfunctional cyanate compound is a novolac polycyanate.