JPH0747633B2 - Polyphenylene ether resin composition containing functional group - Google Patents

Description

TECHNICAL FIELD The present invention relates to a polyphenylene ether resin containing a functional group, and more specifically, it has flame retardancy and curability by partially introducing bromine and propargyl groups. The present invention relates to a polyphenylene ether resin applied at the same time, a method for producing the same, and a cured polyphenylene ether resin containing a functional group having excellent flame retardancy, chemical resistance, and heat resistance, which is obtained by curing a polyphenylene ether resin containing the functional group.

[Conventional technology]

In recent years, there has been a remarkable trend toward miniaturization and high density of mounting methods in the field of electronic devices for communication, consumer use, industrial use, etc., and accordingly, better heat resistance in terms of materials,
Dimensional stability, electrical characteristics, and flame retardancy are being demanded. For example, as a printed wiring board, a copper-clad laminate having a thermosetting resin such as a phenol resin or an epoxy resin as a base material has been conventionally used. Although these have various performances in a well-balanced manner, they have the drawback of poor electrical characteristics, especially dielectric characteristics in the high frequency region. Polyphenylene ether has recently attracted attention as a new material for solving this problem, and its application to copper-clad laminates has been attempted.

It is an engineering plastic with excellent mechanical and electrical properties of polyphenylene ether, and has relatively high heat resistance. However, when it is intended to be used as a printed circuit board material, extremely high heat resistance of solder is required, so that the heat resistance inherent to polyphenylene ether cannot be said to be sufficient. That is, polyphenylene ether is 20
When it is exposed to a high temperature of 0 ° C or higher, it deforms, causing a significant decrease in mechanical strength and peeling of the copper foil formed on the resin surface for circuits. Further, polyphenylene ether has strong resistance to acids, alkalis and hot water, but has extremely weak resistance to aromatic hydrocarbon compounds and halogen-substituted hydrocarbon compounds and is soluble in these solvents.

From the viewpoint of flame retardancy, it is hard to say that polyphenylene ether has sufficient flame retardance to withstand the requirements as a printed circuit board material.

As one of methods for improving the heat resistance and chemical resistance of polyphenylene ether, a method of introducing a crosslinkable functional group into the chain of polyphenylene ether and further curing it to use it as a cured polyphenylene ether has been proposed.

Specific examples include polymers of 2-allyl-6-methylphenol or 2,6-diallylphenol.
It is disclosed in Polymer Science, Vol. 49, p. 267 (1961). U.S. Pat.Nos. 3,281,393 and 34,2062 include:
Copolymers of 2,6-dimethylphenol and 2-allyl-6-methylphenol or 2,6-diallylphenol are disclosed. Further, US Pat. No. 4,634,742 discloses vinyl group-substituted polyphenylene ether.
Furthermore, the present inventors have previously invented a polyphenylene ether substituted with a propargyl group or an allyl group, and a polyphenylene ether containing a triple bond or a double bond, and that these are curable, and the resulting cured product is obtained. Have excellent dielectric properties that are insoluble in aromatic hydrocarbon solvents and halogen-substituted hydrocarbon solvents (Japanese Patent Application Nos. 62-224146, 62-224147 and 62-26).
9459, 62-269460, 63-271983). However, none of the above curable polyphenylene ethers has been improved at all in terms of flame retardancy.

On the other hand, as a method for improving the flame retardancy of polyphenylene ether, a method of introducing bromine into the chain of polyphenylene ether and utilizing it as a brominated polyphenylene ether is known, ACS Symposium Series No. 6, page 178, Amer.
Chem. Soc., Washington, DC, 1975. However, as a matter of course, this brominated polyphenylene ether is soluble in a solvent and has no chemical resistance.

As described above, a technique for simultaneously imparting chemical resistance, heat resistance, and flame retardancy to polyphenylene ether has not been known to date.

[Problems to be Solved by the Invention]

In view of the above circumstances, the present invention intends to provide a polyphenylene ether resin containing a novel functional group having chemical resistance, heat resistance, and flame retardancy while maintaining the excellent dielectric properties of polyphenylene ether. Is.

[Means for Solving the Problems]

As a result of intensive studies to solve the above problems, the present inventors have invented a polyphenylene ether resin containing a functional group having a novel structure that meets the purpose of the present invention.

That is, the present invention relates to (a) a polyphenylene ether resin and (b) a polyphenylene ether resin containing a functional group which is a reaction product of propargyl bromide, wherein the unit (I) represented by the following structural formula and / or ( II), units (III) and units (IV), the bromine content is 1% by weight or more and 30% by weight or less, and the propargyl group content defined by the following formula is 0.1% by mole or more and 100% or more. Mol%
A polyphenylene ether resin containing a functional group characterized by the following:

The invention will be described in detail below.

The polyphenylene ether resin used in the present invention is represented by the following general formula.

QJ-H] _m (V) In the formula, m is an integer of 1 or 2, and J is a polyphenylene ether chain substantially composed of units represented by the following general formula: Q represents a hydrogen atom when m is 1, has two phenolic hydroxyl groups in one molecule when m is 2, and has a polymerization-inert substituent at the ortho and para positions of the phenolic hydroxyl group. Represents the residue of a bifunctional phenolic compound.
Representative examples of Q include compounds represented by the following two general formulas.

[In the formula, A ₁ and A ₂ represent the same or different linear alkyl groups having 1 to 4 carbon atoms, X represents an aliphatic hydrocarbon residue and a substituted derivative thereof, an aromatic hydrocarbon residue and an aromatic hydrocarbon residue thereof and substituted derivatives, the aralkyl group and the substituted derivatives thereof, oxygen, sulfur, sulfonyl group, a carbonyl group, two phenyl groups attached directly a _2, a ₂ and X of the coupling position ortho all the phenolic hydroxyl group And para position. ] As a specific example, Etc.

A particularly preferred example of the polyphenylene ether resin of the general formula (V) is poly (2,6-dimethyl-1,4-phenylene ether) obtained by oxidative polymerization of 2,6-dimethylphenol alone. Also, 2,6-dimethylphenol and 2,
A copolymer obtained from the copolymerization of 3,6-trimethylphenol is also a preferred example.

The molecular weight of the polyphenylene ether resin of the general formula (V) is not particularly limited, and it can be used from low molecular weight to high molecular weight, but the viscosity number ηsp / C measured at 30 ° C. in a 0.5 g / dl chloroform solution is particularly high. Those in the range of 0.2 to 1.0 can be used satisfactorily.

The propargyl bromide used in the present invention is a compound represented by the following structural formula.

CH≡CCH ₂ Br The method for producing a polyphenylene ether resin having a functional group of the present invention comprises a step of metallizing the polyphenylene ether resin of the general formula (V) with an organic metal, and then subjecting it to a substitution reaction with propargyl bromide. Examples of the organic metal include methyllithium, n-butyllithium, sec-butyllithium, tert-butyllithium, phenyllithium and the like, and n-butyllithium can be particularly favorably used.

This reaction can be carried out in an ether solvent such as tetrahydrofuran (hereinafter abbreviated as THF), 1,4-dioxane and dimethoxyethane, and cyclohexane in the presence of N, N, N ′, N′-tetramethylethylenediamine, It can also be carried out using a hydrocarbon solvent such as benzene, toluene or xylene. In the actual reaction, these solvents are preferably used after being subjected to pretreatment such as purification and dehydration, and even if they are mixed at an appropriate ratio, one or two or more solvents other than the above which do not inhibit the reaction May coexist. It is particularly preferable to carry out this reaction in an atmosphere of an inert gas such as nitrogen or argon.

The reaction temperature and reaction time for carrying out this reaction are not particularly limited, but for the metallization reaction, the temperature is more than -78 ° C (the freezing point of the system for solidifying) to the boiling point of the system. Preferably between -78 ° C (the freezing point of the system for those that solidify) and 50 ° C, the time is from 1 second to
It is carried out for 5 hours, more preferably for 1 minute to 3 hours. Also for the substitution reaction with propargyl bromide, the temperature is between -78 ° C (the freezing point of the system for solidifying) to the boiling point of the system, more preferably -78 ° C (the freezing point of the system for solidifying) to 50 ° C. During the time, 1 second ~
It is carried out for 5 hours, more preferably for 1 minute to 3 hours.

The structure of the polyphenylene ether resin having a functional group of the present invention obtained by the above method will be described. According to the measurement of nuclear magnetic resonance (hereinafter abbreviated as NMR) spectrum, the polyphenylene ether resin having a functional group of the present invention is , Substantially consisting of at least the following three or four units represented by structural formulas.

Also, according to the measurement of the NMR spectrum, the propargyl group and bromine contained in the polyphenylene ether resin containing the functional group of the present invention are both covalently bonded to the polyphenylene ether resin skeleton, and the propargyl group is substantially It has been revealed that the bromine is derived from the structures (I) and (II), and the bromine is substantially derived from the structure (III).

As a proof that the propargyl group and bromine are covalently bonded to the polyphenylene ether resin skeleton, NM
In addition to R, purification results by Soxhlet extraction and reprecipitation can be mentioned. That is, the polyphenylene ether resin containing a functional group of the present invention was Soxhlet extracted with a solvent that does not substantially dissolve the resin, such as ethanol or water.
^No change in the spectrum was observed in the ¹ H- and ¹³ C-NMR measurements, and there was no change in the bromine content in the quantification of bromine by the fluorescent X-ray method described later. Further, the resin was completely dissolved in a solvent such as chloroform and then poured into methanol for reprecipitation. Similarly, no change was observed in the NMR spectrum and the content of bromine.

The mechanism of formation of the structures represented by (I) to (III) in the above reaction has not been exactly known so far. However, it can be explained as follows, for example.

Hay et al., Journal of Polymer Science: PART A-1, 7th
Vol. 691 (1969). Poly (2,6-dimethyl-1,4
-Detailed reports on metallization of (phenylene ether). According to the findings, for example, poly (2,6-
In the reaction of dimethyl-1,4-phenylene ether) with n-butyllithium, lithiation can occur at two positions, the methyl group of the polyphenylene ether chain and the 3.5-position of the phenyl group. The reaction formula is as follows.

Although (VII) is preferentially produced in the early stage of the reaction, the thermodynamically more stable amount of (VIII) is predominant over the reaction time.

Reacting propargyl bromide here according to the method of the present invention produces (II) and (III) as a result of the structure of (VII) and (I) as a result of the structure of (VIII), respectively. It is considered to be a thing. That is, it is considered that (VII) is produced by the nucleophilic substitution reaction of (VII) and propargyl bromide, and (III) is produced by the bromine-lithium exchange reaction between (VII) and propargyl bromide. . Further, it is considered that (I) is produced by the nucleophilic substitution reaction of (VIII) and propargyl bromide.

In this reaction, factors controlling the introduction amount of bromine and propoxy group are reaction temperature, reaction time, kind of solvent,
Examples include the amount of organic metal and the amount of propargyl bromide that are reacted. Although it is possible to control the introduction amount by any factor, it is particularly preferable to control the amount of the organic metal and to add the propargyl bromide in an amount equal to or more than this amount. The amount of the organic metal and the amount of propargyl bromide used here are preferably in the range of 0.001 mol to 5 mol per 1 mol of the phenyl group of the polyphenylene ether.

From the above reaction mechanism, it is considered that the reaction temperature and the reaction time are important as factors controlling the amount of bromine introduced. That is, by keeping the reaction temperature low and shortening the reaction time, it is possible to promote the production of (VII) with respect to (VIII) and increase the amount of bromine introduced.
More specifically, a functional group having a high bromine content is contained by carrying out the reaction at a temperature as low as possible within a range of the above-mentioned reaction temperature and reaction time within a range where a desired amount of bromine and propargyl can be achieved. A polyphenylene ether resin can be obtained.

The content of bromine in the polyphenylene ether resin having a functional group of the present invention is 1% by weight or more based on the resin.
It is in the range of not more than 1% by weight, more preferably not less than 1% by weight
It is in the range of 20% by weight or less. The content of the propargyl group defined by the following formula is 0.1 mol% or more and 100 mol% or less, more preferably 0.5 mol% or more and 50 mol% or less.

When the content of bromine is less than 1% by weight, the improvement of flame retardancy is insufficient, which is not preferable. On the other hand, if it exceeds 30% by weight, the thermal stability decreases, which is not preferable. Further, if the content of the propargyl group is less than 0.1 mol%, the chemical resistance after curing is insufficiently improved, which is not preferable. On the contrary, if it exceeds 100 mol%, it becomes very brittle after curing, which is not preferable.

Examples of the method for determining the content of bromine in the polyphenylene ether resin having a functional group of the present invention include a fluorescent X-ray method. It is also possible to decompose the resin with heat, an acid or the like and then quantify it using a technique such as titration or ion chromatography. On the other hand, examples of the method for determining the content of the propargyl group include an NMR spectrum method and an infrared absorption (hereinafter abbreviated as IR) spectrum method.

The molecular weight of the polyphenylene ether resin containing a functional group of the present invention is not particularly limited, it can be used from low molecular weight to high molecular weight, particularly 30 ℃, viscosity number ηsp / C measured in a chloroform solution of 0.5g / dl Those with a value of 0.2 to 1.0 can be used satisfactorily.

The method of curing the polyphenylene ether resin having a functional group of the present invention is optional, and a method using heat, light, an electron beam or the like can be adopted. In the case of heating, the temperature is not particularly limited, but the temperature is in the range of 240 ° C to 350 ° C, more preferably 260 to 300 ° C, and the time is in the range of 1 minute to 5 hours, more preferably 1 minute to 3 hours. Is.

Further, a radical initiator may be used in combination as a catalyst for the purpose of lowering the temperature during curing or promoting the curing reaction. The preferred amount of initiator is 0.1 based on 100 parts by weight of the resin.
To 10 parts by weight, more preferably 0.1 to 5 parts by weight. If the amount of the initiator is less than 0.1% by weight, the effect of the initiator is not sufficiently exhibited, which is not preferable. Conversely, 10% by weight
If it exceeds the limit, the initiator remains and the dielectric properties deteriorate,
It is not preferable because it becomes a brittle material. Representative examples of radical initiators include benzoyl peroxide, cumene hydroperoxide, and 2,5-dimethylhexane-
2,5-dihydroperoxide, 2,5-dimethyl 2,5-
Di (t-butylperoxy) hexyne-3, di-t-butylperoxide, t-butylcumylperoxide, α, α'-bis (t-butylperoxy-m-isoprovir) benzene, 2,5 -Dimethyl-2,5-di (t-butylperoxy) hexane, dicumyl peroxide,
Di-t-butylperoxyisophthalate, t-butylperoxybenzoate, 2,2-bis (t-butylperoxy) butane, 2,2-bis (t-butylperoxy)
There are peroxides such as, but not limited to, octane, 2,5-dimethyl-2,5-di (benzoylperoxy) hexane, di (trimethylsilyl) peroxide, and trimethylsilyltriphenylsilylperoxide. Although not a peroxide, 2,3-dimethyl-2,3-diphenylbutane can also be used as a radical initiator. When curing by heating using these initiators, the temperature is 100-350.
C., more preferably in the range of 150 to 300.degree. C. and selected according to the decomposition temperature of the initiator. The time is 1 minute to 5 hours, more preferably 1 minute to 3 hours.

The degree of the curing reaction described above can be traced by a differential scanning calorimeter or an IR spectrum method.

Polyphenylene ether resin containing a functional group of the present invention,
In addition to the above-mentioned initiator, it is possible to mix and use a filler and an additive in an amount within a range that does not impair the original performance for the purpose of imparting desired performance depending on the application. The filler may be maintained or powdered, glass fiber, aramid fiber, carbon fiber, boron fiber, ceramic fiber,
Asbestos fibers, carbon black, silica, alumina, talc, mica, glass beads, glass hollow spheres and the like can be mentioned. Examples of the additives include antioxidants, heat stabilizers, antistatic agents, plasticizers, pigments, dyes, colorants and the like. Further, a flame retardant or a flame retardant auxiliary may be used in combination for the purpose of further improving the flame retardancy. Further, it is possible to blend one or more kinds of crosslinkable monomers and other thermoplastic and thermosetting resins.

Examples of the method for shaping the polyphenylene ether resin having a functional group of the present invention alone or by blending with the above-mentioned components include a solvent casting method and a heat melting method. Examples of the solvent used for casting include single or mixed solvents selected from halogen-substituted hydrocarbons such as dichloromethane, chloroform and trichloroethylene and aromatic hydrocarbons such as benzene, toluene and xylene. As the method of heating and melting, methods such as injection molding, transfer molding, extrusion molding and press molding can be used.
The temperature at the time of heating and melting is selected in the range from the glass transition temperature of the resin to the curing start temperature. In the case of the polyphenylene ether resin containing a functional group of the present invention, due to the effect of bromine and propargyl groups introduced into the chain, the glass transition temperature is about 140 to 200 ° C. as compared with polyphenylene ether having no such functional group. It is generally low and advantageous for thermoforming.

Summarizing the features of the polyphenylene ether resin containing a functional group of the present invention described above, firstly, the flame retardancy obtained by introducing bromine can be mentioned. The second feature is
It is excellent in film forming property by the casting method.
Almost no ordinary polyphenylene ether was found to have a solvent film-forming property, whereas the resin of the present invention provided a smooth and sufficiently strong film and was easy to handle.
The third feature is that it is excellent in storage stability and can be stored for a long period of time in the form of a solution or a film without gelling. And the fourth characteristic is that the glass transition temperature is lower than that of ordinary polyphenylene ether and thermoforming is easier to perform. That is, it was shown that the glass transition temperature decreased as the content of bromine and propargyl group increased, as the content of bromine and propargyl group increased.

The features of the method for producing the above-mentioned functionalized polyphenylene ether resin are as follows. Industrially inexpensive raw materials are used, and at a low temperature and in a short time, a one-step reaction causes flame retardancy and curability with respect to existing polyphenylene ether. Can be added at the same time.

Next, a cured polyphenylene ether resin containing a functional group will be described. The functionalized polyphenylene ether resin cured product is obtained by curing the functionalized polyphenylene ether resin of the present invention by a method such as heating.

This means, for example, IR spectroscopy, high resolution NM of solids.
It can be verified by analytical methods such as R spectrum method (so-called CP-MAS) and pyrolysis gas chromatography.

Further, the cured product contains bromine, and the content thereof is in the range of 1% by weight or more and 30% by weight or less based on the cured product,
More preferably, it is in the range of 1% by weight to 20% by weight. When the bromine content is less than 1% by weight, the flame retardancy is poor, which is not preferable. On the other hand, if it exceeds 30% by weight, the thermal stability becomes poor, which is not preferable. The bromine is bromine covalently bonded to the polyphenylene ether skeleton, and is substantially derived from the structure of the above structural formula (III). This can be verified by the analysis of the chloroform extract described below.

As a method for quantifying the bromine contained in the cured product, for example, a fluorescent X-ray method can be mentioned. It is also possible to decompose the cured product with heat, an acid or the like and then quantify it using a technique such as titration or ion chromatography.

The chloroform extraction rate of the cured product is in the range of 0.01% by weight to 20% by weight, more preferably 0.01% by weight to 10% by weight.
It is within the range of weight% or less. If the extraction rate is less than 0.01% by weight, the cured product becomes brittle, which is not preferable. On the other hand, if it exceeds 20% by weight, the improvement in chemical resistance is insufficient, which is also not preferable. The chloroform extraction rate here is a value obtained by immersing the cured product in chloroform at 23 ° C. for 12 hours, and is calculated according to the following formula based on the weight of the cured product before immersion in chloroform.

The shape of the cured product immersed in chloroform is most preferably a film or powder in consideration of the ease of removing chloroform.

Chloroform extraction rate can be measured by using deuterated chloroform instead of chloroform. In this case, it is possible to know the components of the extract and its structure by measuring the NMR spectrum of the deuterated chloroform solution of the extract. it can. This extract was obtained by extracting a component of the polyphenylene ether resin having a functional group of the present invention that could not sufficiently contribute to the curing reaction in the curing process. Therefore, in the extract, as in the case of the polyphenylene ether resin having a functional group of the present invention, the structures represented by the above formulas (I) and / or (II) and (III) are confirmed.

As a means for confirming the structure of the extract, the NMR spectrum method is effective as described above, and of these, ¹ H-NMR is particularly effective. The IR spectrum method can also be used.

Summarizing the characteristics of the cured polyphenylene ether resin containing the functional group described above, the first characteristic is chemical resistance and heat resistance obtained by curing. That is, the resistance to a halogen-substituted hydrocarbon solvent or an aromatic hydrocarbon solvent was remarkably increased, and no change in appearance was observed even when heated in a solder bath at 260 ° C. The second feature is flame retardancy due to the effect of bromine. The third feature is that the excellent dielectric properties (low dielectric constant, low dielectric loss tangent) of polyphenylene ether are not impaired. Furthermore, since the curing reaction in the present invention occurs by the addition reaction of the propargyl group in the polyphenylene ether resin containing a functional group,
Unlike polyimide resin, it also has a feature that it does not generate by-products such as water and gas due to the condensation reaction, and becomes a uniform and void-free cured product.

〔Example〕

Hereinafter, the present invention will be described with reference to examples in order to further clarify the present invention, but the scope of the present invention is not limited to these examples.

Example 1 Polyphenylene ether resin containing a functional group Viscosity number ηs measured at 30 ° C. in a 0.5 g / dl chloroform solution
Dissolve 10.0 g of poly (2,6-dimethyl-1,4-phenylene ether) with p / C of 0.55 in 200 ml of tetrahydrofuran, add 55.5 ml of n-butyllithium (1.5 mol / hexane solution), and add nitrogen atmosphere. The reaction was carried out at 25 ° C for 5 minutes. Then, add 10g of propargyl bromide and add it at 25 ℃.
The mixture was stirred as it was for 30 minutes. Finally 500 ml of methanol
The mixed solution of was added to precipitate the polymer. After repeating filtration and washing with methanol 5 times, vacuum drying was carried out at 80 ° C. for 14 hours to obtain a powdery polymer. The analytical values of this polymer are summarized in Table 1. Each value was obtained by the following method.

1. Viscosity number ηsp / C: 30 ° C, 0.5g / dl, chloroform solution 2. Bromine content: fluorescent X-ray method 3. Propargyl group content: ¹ H-NMR Next, this polymer is dissolved in trichloroethylene and then cast. A film was formed. The obtained film had a thickness of about 100 μm and had excellent surface smoothness and sufficient strength. When a part of the film was cut out and measured by a thermomechanical analyzer (hereinafter abbreviated as TMA), the glass transition temperature was 187 ° C. Further, this film did not cause gelation even if left at room temperature for 3 months, and was excellent in long-term storage stability.

Polyphenylene ether resin cured product containing a functional group 18 films obtained by the above method are stacked and vacuum-pressed from room temperature to 280 ° C by a vacuum press, held at 280 ° C for 30 minutes, and then cooled to a thickness of about 1.6 mm. A sheet-shaped cured product of was obtained. The physical properties of this cured product are summarized in the table. The measurement of each physical property was performed by the method described below.

1. Chloroform extraction rate A part of the sheet-shaped cured product was ground with a file to make a fine powder, immersed in chloroform at 23 ° C for 12 hours, and the weight before and after that was calculated according to the following formula.

2. Flammability A test piece with a length of 127 mm and a width of 12.7 mm was cut out and tested according to the UL-94 test method.

3. Solder heat resistance A 10 mm square test piece is floated in a solder bath at 260 ° C for 120 seconds,
The change in appearance was visually observed.

4. Dielectric constant and dielectric loss tangent were measured at 1MHz.

On the other hand, the following analysis was performed to confirm the structure of this cured product. First, the FT-IR (diffuse reflection method) of the finely powdered cured product was measured to confirm the skeleton of polyphenylene ether. The attribution of the main peak was as follows.

νs, νas CH ₃ , CH ₂ (3027〜2862cm ^-1 ) νsC ＝ C (1603cm ^-1 ) δsCH ₃ (1381cm ^-1 ) νasO-C (1190cm ^-1 ) In the measurement of pyrolysis gas chromatography (pyrolysis condition: 590 ° C, 4 seconds), 2-methyl which is a pyrolysis product specific to polyphenylene ether. Phenol, 2,6-dimethylphenol, 2,4-dimethylphenol and 2,4,6
-Trimethylphenol was confirmed. The peak of the gas chromatograph was identified by using a commercially available reagent as a standard and comparing the retention time, the mass spectrum, and the FT-IR spectrum.

Then, the fine powder of the hardened material was added to deuterated chloroform (CDCl ₃ ) to remove the powder.
Extraction was performed by immersing at 12 ° C for 12 hours. When this deuterated chloroform solution was transferred to an NMR sample tube and ¹ H-NMR was measured,
Characteristic peaks were confirmed in the above structures (I) to (III). The attributions of the main peaks are as follows.

1.8 to 1.9 ppm ((C) CH ^{* of} (I) to (II) 2.0 to 2.15 ppm (methyl group of (I) to (III)) Example 2 Polyphenylene ether resin containing a functional group In Example 1, the reaction conditions for n-butyllithium were 25
The reaction was carried out in exactly the same manner except that the temperature was changed from 5 minutes to 25 ° C for 15 minutes. The analytical values of the obtained polymer are shown in Table 1.

Then 100 parts by weight of this polymer and 2,5-dimethyl-2,5-di (t-butylperoxy) hexyne-3 as an initiator
3 parts by weight of Perhexin 25B (Nippon Oil & Fats Co., Ltd.) was dissolved in trichlorethylene, and a film was formed by a casting method. The obtained film had a thickness of about 100 μm and had excellent surface smoothness and sufficient strength. Also, this film does not gel when left at room temperature for 3 months,
It was excellent in long-term storability.

Polyphenylene ether resin cured body containing a functional group 18 pieces of the film obtained by the above method are heated and compressed from room temperature to 280 ° C. by a vacuum press, held at 280 ° C. for 30 minutes, and then cooled to a thickness of about 1.5 mm. A sheet-shaped cured body was obtained.
The physical properties of this cured product are summarized in the table. The physical properties were measured in the same manner as in Example 1.

The structural analysis of the cured product was performed in the same manner as in Example 1.
That is, the polyphenylene ether skeleton was confirmed using FT-IR and pyrolysis gas chromatography. Further, ¹ H-NMR of the deuterated chloroform extract was measured, and the characteristic peaks in the above structural formulas (I) to (III) were confirmed.

Example 3 Polyphenylene ether resin containing functional group 2,2-bis (3,5-dimethyl-4-hydroxyphenyl)
Tetrahydrofuran 200 ml of 10 g of polyphenylene ether resin having a hydroxyl number at both ends obtained by oxidative polymerization of 2,6-dimethylphenol in the presence of propane and having a viscosity number of 0.40
And n-butyllithium (1.5 mol /, hexane solution) (110 ml) were added, and the mixture was reacted at 25 ° C. for 20 minutes in a nitrogen atmosphere. Subsequently, 20 g of propargyl bromide was added, and the mixture was stirred at 25 ° C for another 30 minutes. Finally, the reaction mixture was poured into 1.0 of methanol to precipitate a polymer. After repeating filtration and washing with methanol three times, 80 ℃
Vacuum dried for 14 hours to obtain a powdery polymer. The analytical values of this polymer are summarized in Table 1.

When this polymer was dissolved in trichlorethylene and formed into a film by the casting method, a film having a smooth surface and sufficient strength was obtained. Furthermore, this film does not gel even if left at room temperature for 3 months,
It was excellent in long-term storability.

Cured Polyphenylene Ether Resin Containing Functional Group Using the film obtained by the above method, a cured sheet was prepared in exactly the same manner as in Example 1 and its physical properties were measured.
The results are summarized in the table.

The structural analysis of the cured product was performed in the same manner as in Example 1.
That is, the polyphenylene ether skeleton was confirmed using FT-IR and pyrolysis gas chromatography. Further, ¹ H-NMR of the deuterated chloroform extract was measured, and the characteristic peaks in the above structures (I) to (III) were confirmed.

[Comparative example]

In Example 1, the reaction conditions for n-butyllithium were set to 25
The reaction was conducted in exactly the same manner except that the temperature was changed from 5 minutes to 40 ° C. for 1 hour. The analytical values of the obtained polymer are shown in Table 1. No bromine was detected in this polymer as determined by fluorescent X-ray method.

A sheet-shaped cured product was produced in the same manner as in Example 1 using this polymer, and its physical properties were measured. The results are summarized in Table 1.
It was inferior in flame retardance because it had no effect of bromine.

EFFECTS OF THE INVENTION A feature of the polyphenylene ether resin containing a functional group of the present invention is firstly flame retardancy obtained by introducing bromine. The second characteristic is that the film forming property by the casting method is excellent. Almost no ordinary polyphenylene ether was found to have a solvent film-forming property, whereas the resin of the present invention provided a smooth and sufficiently strong film and was easy to handle. The third feature is that it is excellent in storage stability and can be stored for a long period of time in the form of a solution or a film without gelling. And the fourth feature
Is that it has a lower glass transition temperature than ordinary polyphenylene ether and is easily thermoformed. That is, it was shown that the glass transition temperature decreased as the content of bromine and propargyl group increased, as the content of bromine and propargyl group increased.

The feature of the method for producing the above-mentioned functionalized polyphenylene ether resin is that industrially inexpensive raw materials are used, and at a low temperature and in a short time, a one-step reaction simultaneously imparts flame retardancy and curability to existing polyphenylene ether. The point is that you can.

The characteristics of the cured polyphenylene ether resin containing a functional group are firstly the chemical resistance and heat resistance obtained by curing. That is, the resistance to a halogen-substituted hydrocarbon solvent or an aromatic hydrocarbon solvent was remarkably increased, and no change in appearance was observed even when heated in a solder bath at 260 ° C. Second
Is characterized by flame retardancy due to the effect of bromine. The third feature is that the excellent dielectric properties (low dielectric constant, low dielectric loss tangent) of polyphenylene ether are not impaired. Furthermore, since the curing reaction in the present invention occurs by the addition reaction of the propargyl group in the functionalized polyphenylene ether resin, byproducts such as water and gas due to the condensation reaction unlike the polyimide resin are not generated and the voids are uniform and void. It also has the feature of becoming a cured product without

All of the features of the present invention described above indicate that the present invention can be advantageously used as a flame retardant low dielectric constant printed circuit board material. That is, it is useful as a material for a single-sided or double-sided copper clad laminate, a prepreg for a multilayer board, a flexible board, a three-dimensional printed board by injection molding, and the like. Other applications include semiconductor encapsulation materials, satellite broadcast antenna substrates, VLSI insulating films, microwave oven materials, heat-resistant adhesives, and the like.

Claims (1)

[Claims] 1. A polyphenylene ether resin containing a functional group which is a reaction product of (a) a polyphenylene ether resin and (b) a propargyl bromide, which comprises a unit (I) and / or () represented by the following structural formula. II), units (III) and units (IV), the bromine content is 1% by weight or more and 30% by weight or less, and the propargyl group content defined by the following formula is 0.1% by mole or more and 100% or more. A polyphenylene ether resin containing a functional group, which is characterized by being at most mol%.