JPH0747632B2 - Functionalized polyphenylene ether resin composition - Google Patents

Description

TECHNICAL FIELD The present invention relates to a functionalized polyphenylene ether resin,
More specifically, a polyphenylene ether resin having flame retardancy and curability simultaneously imparted by partially introducing bromine and allyl groups, a method for producing the same, and a flame retardancy obtained by curing the functionalized polyphenylene ether resin. , A functionalized polyphenylene ether resin cured product having excellent chemical resistance and heat resistance.

[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.

Polyphenylene ether is an engineering plastic with excellent mechanical and electrical properties, 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. Was insoluble in aromatic hydrocarbon solvents and halogen-substituted hydrocarbon solvents and had excellent dielectric properties (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 Present Invention]

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

[Means for Solving the Problems]

As a result of intensive studies to solve the above problems, the present inventors have invented a functionalized polyphenylene ether resin having a novel structure in accordance with the object of the present invention. The present invention comprises the following inventions.

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

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

CH ₂ = CHCH ₂ Br The method for producing the functionalized polyphenylene ether resin of the present invention comprises the steps of metallating a polyphenylene ether resin of the general formula (V) with an organometal, followed by substitution reaction with allyl bromide. Examples of organic metals include methyl lithium, n-butyl lithium, sec-butyl lithium, and ter.
Examples thereof include t-butyllithium and phenyllithium, and especially n-butyllithium can be 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. Regarding the substitution reaction with allyl bromide,
Temperature is -78 ° C (freezing point of system for solidifying) ~
During the boiling point of the system, more preferably between −78 ° C. (the freezing point of the system for those that solidify) and 50 ° C., the time is between 1 second and 5 hours, and more preferably between 1 minute and 3 hours. Be seen.

The structure of the functionalized polyphenylene ether resin of the present invention obtained by the above-mentioned method will be described. According to the measurement of nuclear magnetic resonance (hereinafter abbreviated as NMR) spectrum, the functionalized polyphenylene ether resin of the present invention is at least It is substantially composed of units represented by 3 to 4 structural formulas.

Also, according to the measurement of the NMR spectrum, the allyl group and bromine contained in the functionalized polyphenylene ether resin of the present invention are both covalently bonded to the polyphenylene ether resin skeleton, and the allyl group is substantially the above ( I)
And (II) structure, bromine is substantially (II
It is known to be derived from the structure of I).

As a proof that the allyl group and bromine are covalently bonded to the polyphenylene ether resin skeleton, there are purification results by Soxhlet extraction and reprecipitation in addition to NMR. That is, the solvent of the functionalized polyphenylene ether resin of the present invention do not substantially dissolve the resin, for example, ethanol or water was Soxhlet extraction, ¹ H- and ¹³ C
No change in the spectrum was observed in the NMR measurement, 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.

The reaction of allyl bromide here according to the method of the invention is attributed to the structure of (VII) (I
I) and (III) are considered to be produced by (I), respectively, due to the structure of (VIII). That is, it is considered that (II) is produced by the nucleophilic substitution reaction of (VII) and allyl bromide, and (III) is produced by the bromine-lithium exchange reaction between (VII) and allyl bromide. . Further, it is considered that (I) is produced by the nucleophilic substitution reaction of (VIII) and allyl bromide.

In the present reaction, factors controlling the introduction amount of bromine and allyl groups include reaction temperature, reaction time, type of solvent, amount of organic metal to be reacted and amount of allyl bromide. 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 add allyl bromide in an amount equal to or more than that. The amount of organic metal and the amount of allyl bromide used here are based on the phenyl group 1 of polyphenylene ether.
The range of 0.001 mol-5 mol is preferable with respect to mol.

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, within the range where the desired bromine and allyl group contents can be achieved, the functionalization with a high bromine content can be performed by carrying out the reaction at the lowest possible temperature and for the shortest time within the above reaction temperature and reaction time range. A polyphenylene ether resin can be obtained.

The content of bromine in the functionalized polyphenylene ether resin of the present invention is from 1% by weight to 30% by weight based on the resin.
It is in the following range, and more preferably in the range of 1% by weight to 20% by weight. The content of the allyl 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 5 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. In addition, the content of allyl groups
When it 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 functionalized polyphenylene ether resin 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, as a method for determining the content of the allyl group,
Examples thereof include NMR spectrum method and infrared absorption (hereinafter abbreviated as IR) spectrum method.

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

The method of curing the functionalized polyphenylene ether resin of the present invention is optional, and methods such as heat, light, and electron beam can be used. When heated, the temperature is not particularly limited, but the temperature is 240 ° C to 350 ° C, and more preferably 260.
To 300 ° C., and the time is 1 minute to 5 hours, more preferably 1 minute to 3 hours.

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-isopropyl) 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 depending on 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.

The functionalized polyphenylene ether resin of the present invention contains, in addition to the above-mentioned initiator, an amount of a filler or an additive in a range that does not impair the original performance for the purpose of imparting desired performance depending on its use. Can be used. The filler may be maintained or powdered, and may be glass fiber, aramid fiber, carbon fiber, boron fiber, ceramic fiber, asbestos fiber, carbon black, silica, alumina, talc, mica, glass beads, glass. A hollow sphere etc. 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.

The functionalized polyphenylene ether resin of the present invention alone,
Alternatively, as a method of blending with the above components and shaping,
For example, a solvent casting method and a heat melting method can be mentioned. As the solvent used for casting,
Specific examples thereof include halogen-substituted hydrocarbons such as dichloromethane, chloroform and trichloroethylene, aromatic hydrocarbons such as benzene, toluene and xylene, and a single solvent or a mixed solvent thereof. Further, as a method by heating and melting, injection molding, transfer molding,
Methods such as 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 functionalized polyphenylene ether resin of the present invention, due to the effect of the bromine and allyl groups introduced in the chain, the glass transition temperature is about 140 to 2 as compared to polyphenylene ether without these functional groups.
It is as low as 00 ℃, which is advantageous for thermoforming.

Summarizing the features of the functionalized polyphenylene ether resin of the present invention described above, firstly, the flame retardancy obtained by introducing bromine can be mentioned. The second characteristic is that it is superior to the film forming method by the casting method. Almost no solvent film formation method was observed with ordinary polyphenylene ether, whereas with the resin of the present invention, a smooth and sufficiently strong film was obtained and handling was easy. 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, there was a phenomenon that the glass transition temperature was lowered as the content of bromine and allyl groups was increased due to the effect of the introduction of bromine and allyl groups.

The characteristics of the method for producing the above-mentioned functionalized polyphenylene ether resin are as follows: using industrially inexpensive raw materials, at low temperature and in a short time, by general reaction, flame retardancy and curability with respect to existing polyphenylene ether. Can be added at the same time.

Next, the functionalized polyphenylene ether resin cured product will be described. This 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 can be verified by analytical methods such as IR spectroscopy, solid high resolution NMR spectroscopy (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 components of the functionalized polyphenylene ether resin of the present invention that could not sufficiently contribute to the curing reaction during the curing process. Therefore, in the extract, as in the case of the functionalized polyphenylene ether resin of the present invention, the above formula (I) and / or (I
The structures represented by I) 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 features of the functionalized polyphenylene ether resin cured product described above, the first feature is 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. 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 occurs by the addition reaction of the allyl group in the functionalized polyphenylene ether resin, byproducts such as water and gas due to the condensation reaction unlike the epoxy resin and the polyimide resin are not generated, and a uniform void It also has the feature that it becomes a 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 Functionalized polyphenylene ether resin Viscosity number ηs measured with a 0.5 g / dl chloroform solution at 30 ° C.
Dissolve 10.0 g of poly (2,6-dimethyl-1,4-phenylene ether) with a p / C of 0.55 in 200 ml of THF, add 11.1 ml of n-butyllithium (1.5 mol / hexane solution), and add nitrogen atmosphere. The mixture was reacted at 25 ° C for 5 minutes. Subsequently, 1.5 g of allyl bromide was added, and the mixture was stirred at 25 ° C for another 30 minutes. Finally, a mixed solution of 80 ml of water and 88 ml of methanol was added to precipitate a polymer. 5 filtration and washing with methanol
After repeating the process once, it was vacuum dried at 80 ° C. for 14 hours to obtain a white 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. Allyl group content: ¹ H-NMR Next, this polymer is dissolved in trichlorethylene 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 190 ° 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.

Functionalized polyphenylene ether resin cured product 18 films obtained by the above method are stacked and compressed by heating 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 hardened body 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.

1.9 to 2.4 ppm ((I) to (III) methyl group) 4.8 to 5.1 ppm ((I) and (II) —CH ₂ CH = CH ₂ ^* ) 5.65 to 5.85 ppm ((I) —CH _{2 ^{CH * = CH 2) 5.95~6.1ppm -CH}} 2 CH * = CH 2 of ((II)) 6.3 to 6.7 ppm (phenyl groups of (I) and (II)) Example 2 Functionalized polyphenylene ether resin In Example 1, the reaction condition of n-butyllithium was 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.

Functionalized polyphenylene ether resin cured product 18 films obtained by the above method are stacked and compressed by heating from room temperature to 240 ° C by a vacuum press, held at 240 ° C for 30 minutes, and then cooled to form a sheet with a thickness of about 1.5 mm. A cured product 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 Functionalized Polyphenylene Ether Resin The same poly (2.6-dimethyl-1,4 as used in Example 1
-Phenylene ether) 8.0 g is dissolved in THF 400 ml,
-Butyllithium (1.5mol /, hexane solution) 88.9m
l was added thereto and reacted at 25 ° C. for 20 minutes under a nitrogen atmosphere. Then, add 11.5 ml of allyl bromide and keep at 25 ℃.
Stir for 30 minutes. Finally add the reaction mixture to methanol 1.
It was poured into 0 to precipitate a polymer. After repeating filtration and methanol washing three times, vacuum drying was carried out at 80 ° C. for 14 hours to obtain a white 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.

Functionalized polyphenylene ether resin cured product Using the film obtained by the above method, a sheet-shaped cured product was prepared in exactly the same manner as in Example 1 and its physical properties were measured.
The results are summarized in Table 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 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] The features of the functionalized polyphenylene ether resin of the present invention are:
First, it is flame retardant 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 characteristic is that the glass transition temperature is lower than that of ordinary polyphenylene ether and thermoforming is easier to perform. That is, there was a phenomenon that the glass transition temperature was lowered as the content of bromine and allyl groups was increased due to the effect of the introduction of bromine and allyl groups.

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 functionalized polyphenylene ether resin cured product are firstly 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 allyl group in the functionalized polyphenylene ether resin,
Unlike epoxy resins, water and gas by-products due to the condensation reaction are not generated, and the resulting cured product is uniform and has no voids.

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 functionalized polyphenylene ether resin which is a reaction product of (a) a polyphenylene ether resin and (b) an allyl bromide, wherein units (I) and / or (II) are represented by the following structural formulas. And unit (III) and unit (IV), the bromine content is 1% by weight or more
A functionalized polyphenylene ether resin, which is 30% by weight or less and the content of allyl groups defined by the following formula is 0.1 mol% or more and 100 mol% or less.