JP2003055453A - Method of preparing novel functionalized polyphenylene ether - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a method of preparing a functionalized polyphenylene ether high in production efficiency and good in workability. SOLUTION: In this method of preparing a functionalized polyphenylene ether, a polyphenylene ether (A) is reacted with at least a functionalizing compound (B) having at least a carbon-carbon double bond or a triple bond, and at least a functional group selected from the group consisting of a carboxyl group, oxidized acyl group, imino group, imide group, hydroxyl group, and glycidyl group, at a temperature not higher than the melting point of the polyphenylene ether, and the polyphenylene ether particles having a particle diameter not larger than 10 μm are not more than 20 wt.%.

Description

Detailed Description of the Invention

[0001]

TECHNICAL FIELD The present invention relates to a functionalized polyphenylene ether which can be used as a plastic material for electric and electronic products, automobiles and various other industrial materials, foods and packaging fields.

[0002]

2. Description of the Related Art Polyphenylene ether is excellent in processing and productivity and can efficiently produce products and parts having a desired shape by a molding method such as a melt injection molding method and a melt extrusion molding method. Various industrial material fields,
It is widely used as a material for products and parts in the food and packaging fields. In recent years, particularly in the electric / electronic fields, automobile fields, and other various industrial fields, products and parts are diversified, and requirements for resin materials are becoming wider.

In order to meet this demand, a resin material having material properties which are not present in existing materials has been developed by a polymer alloy technology by compounding different kinds of materials or combining various existing polymer materials. Ordinary polyphenylene ether has high heat resistance and excellent mechanical properties, but since it has a poor affinity with other materials, the material of the other party that can be composited is limited. In particular, the affinity with highly polar materials such as polyamide is very poor, and functionalized polyphenylene ether is required to form a composite with such a resin.

As a means for obtaining a functionalized polyphenylene ether, for example, Japanese Patent Application Laid-Open No. 12-191769 discloses a method of reacting a solid polyphenylene ether with a functionalized compound. A commonly known form of solid polyphenylene ether is pellets or powders, of which the pellets have substantially no reaction between the polyphenylene ether and the functionalized compound. Further, even in the case of powder, the powder adheres to the inner wall of the reactor during the reaction operation, so that the thermal conductivity from the jacket heat medium to the reactor decreases. As a result, does it take a long time to raise the powder temperature in the reactor to the target temperature?
It stabilizes at a temperature below the target temperature, which is an undesirable phenomenon from the viewpoint of reaction rate. In addition to this, problems such as a large amount of powder scattering occur.

[0005]

SUMMARY OF THE INVENTION The present invention provides a method for producing a functionalized polyphenylene ether, which has a high reaction rate and a high temperature rising rate, and thus has a high production efficiency, and has a small amount of powder scattering, which has a good operability.

[0006]

Means for Solving the Problems As a result of earnest studies on a method for producing a functionalized polyphenylene ether, the present inventor has found that a method of contacting a powder of polyphenylene ether with a functionalized compound has a particle size of 10 μm or less. The present inventors have found that the amount of fine powder has a great influence on the reaction rate and handleability, and have reached the present invention. That is, the present invention relates to (A) polyphenylene ether and (B) at least one carbon atom in the molecule.
A carbon double or triple bond, and a carboxyl group,
In the method of reacting at least one functionalized compound having at least one functional group selected from the group consisting of an acyl oxide group, an imino group, an imide group, a hydroxyl group and a glycidyl group at a temperature not higher than the melting point of polyphenylene ether, A method for producing a functionalized polyphenylene ether, comprising 20% by weight or less of polyphenylene ether particles having a diameter of 10 μm or less.

The present invention will be described in detail below. The polyphenylene ether used in the present invention has a structure of the following (formula 1), and a reduced viscosity of a chloroform solution of 0.5 g / dl at 30 ° C. is in the range of 0.15 to 1.0 dl / g, more preferably 0. It is a polymer or copolymer in the range of 20 to 0.70 dl / g.

[0008]

[Chemical 1]

(R1, R2, R3 and R4 each independently represent a hydrogen atom, an alkyl group or a halogen atom.) Specifically, poly (2,6-dimethyl-1,4-phenylene ether), Poly (2-methyl-6-phenyl-1,4-phenylene ether), poly (2-methyl-6)
-Phenyl-1,4-phenylene ether), poly (2,6-dichloro-1,4-phenylene ether) and the like.

Specific examples of the copolymer include 2,6-dimethylphenol and other phenols (for example, 2,3,6).
Examples include polyphenylene ether copolymers such as copolymers with -trimethylphenol and 2-methyl-6-methylbutylphenol). Above all, poly (2,6
-Dimethyl-1,4-phenylene ether), 2,6-
A copolymer of dimethylphenol and 2,3,6-trimethylphenol can be preferably used, most preferably poly (2,6-dimethyl-1,4-phenylene ether).
Is.

The polyphenylene ether used in the present invention can be used in the form of powder or pellets, but powder is preferred. In the case of pellets, the contact area between the polyphenylene ether and the functionalized compound is low, so that the functionalization reaction is practically rare. The powdery polyphenylene ether can be obtained by, for example, a method of finely pulverizing pellets or a method of adding a poor solvent such as methanol or acetone to a solution of polyphenylene ether dissolved in a good solvent such as toluene or xylene.

The particle diameters of the powders obtained by these methods are widely distributed, but most of them are from 1 μm to 1,000 μm.
Is the range. Of these, fine particles of 10 μm or less tend to adhere to the inner wall of the reactor, and the layer formed by the adhesion lowers thermal conductivity when heated from the outer jacket of the reaction tank. As a result, it takes a long time to raise the powder temperature in the reactor to the target temperature or stabilizes at a temperature equal to or lower than the target temperature, which is an undesirable phenomenon from the viewpoint of reaction rate.

Further, fine particles are not preferable in terms of operation. For example, when the powder and the gas of the functionalized compound are stirred as a reaction operation, the fine particles are entrained in the vent gas and cause troubles such as clogging of the bag filter of the vent gas treatment facility and scaling of the heat exchanger.
For the above reasons, it is preferable that the content of the fine particles of 10 μm or less in the total powder of polyphenylene ether is 20% by weight or less, and the particularly preferable range is 10% by weight or less.

As the particle size increases, the above reaction rate and temperature control rate decrease, and the problems of handling the powder tend to be alleviated. In particular, when the particle diameter is 100 μm or more, almost no adhesion to the inner wall of the reaction vessel or formation of aggregates is observed, and even when a gas containing a functionalized compound is blown in, almost no particles are scattered in the normal gas linear velocity range. Absent. For the above reasons, it is preferable that the total particle diameter of the polyphenylene ether powder is 100 μm or more, and 30% by weight or more.

The functionalized compound used in the present invention is a group consisting of at least one carbon-carbon double bond or triple bond in the molecule and a carboxyl group, an acyl oxide group, an imino group, an imide group, a hydroxyl group and a glycidyl group. It is at least one organic compound having at least one functional group selected from Among these functionalized compounds, compounds having a double bond and at least one carboxyl group, acyl oxide group and imide group in the molecule are preferable.

Specific examples thereof include maleic anhydride, maleic acid, fumaric acid, phenylmaleimide, itaconic acid, glycidyl methacrylate and glycidyl acrylate, with maleic anhydride being preferred. The state of the functionalized compound supplied to the polyphenylene ether in the present invention is not particularly limited, but it is preferably liquid or gas. Examples of the method of supplying in a gas state include a method of directly supplying a gasified functionalized compound and a method of supplying by diluting with an inert gas. Examples of the inert gas include helium, argon and nitrogen, with nitrogen being particularly preferable.

The temperature at which the functionalized compound and the polyphenylene ether are reacted in the present invention is room temperature or higher, preferably 150 ° C. or higher. Further, the higher the reaction temperature, the higher the reaction rate, but in order to maintain the color tone of the polyphenylene ether, the reaction temperature should be below the melting point of the polyphenylene ether,
It is less than 0 ° C. References showing the relationship between crystalline polyphenylene ether and its melting point include, for example, Journal.
al of Polymer Science, Par
tA-2 (6) 1141-1148 (1968),
European Polymer Journal
(9) pp. 293-300 (1973), Polymer
r (19) 81-84 (1978).

In the present invention, the melting point of polyphenylene ether is 2 in the differential scanning calorimeter (DSC) measurement.
It is defined as the peak top temperature of the peak observed in the temperature-heat flow rate graph obtained when the temperature is raised at 0 ° C / min.
In the present invention, the melting point of polyphenylene ether is defined as the highest temperature among the peak top temperatures when there are plural peak top temperatures. In the method for producing a functionalized polyphenylene ether of the present invention, the polyphenylene ether is in the form of powder obtained by precipitation from a solution and has a melting point of 150 to 26.
It is preferably 0 ° C.

In the present invention, a radical initiator may be added to accelerate the reaction. An organic peroxide is preferably used as the radical initiator. In the present invention,
When the gaseous functionalized compound and the polyphenylene ether are brought into contact with each other and reacted, the polyphenylene ether may be left standing in the reaction vessel or may be stirred. The reaction device in the case of reacting with stirring is not particularly limited,
A Henschel mixer, a paddle mixer, and a paddle dryer are mentioned as an example, and a Henschel mixer is especially preferable.

[0020]

BEST MODE FOR CARRYING OUT THE INVENTION Next, the present invention will be described in more detail with reference to Examples, but the present invention should not be limited to these Examples. <Evaluation method> 1. Amount of maleic anhydride added to the functionalized polyphenylene ether First, the reaction product was heated using a Soxhlet extractor to remove unreacted maleic anhydride remaining in the functionalized polyphenylene ether powder after the reaction. It was washed with acetone for 3 hours or more. When the functionalized polyphenylene ether after the reaction was pellets, this washing operation was performed after sufficiently pulverizing in a mortar to make powder.

The polymer after washing is heated to 150 ° C. and 0.1 mm
It was dried under reduced pressure for 1 hour under Hg conditions. The fact that unreacted maleic anhydride does not remain in the functionalized polyphenylene ether after drying means that the powder of polyphenylene ether after drying is dissolved in chloroform and the solution is analyzed by gas chromatography, the peak corresponding to maleic anhydride being completely Confirmed by disappearance. The amount of maleic anhydride added to the functionalized polyphenylene ether after washing and drying was quantified by titration using phenolphthalein as an indicator. Specifically, 1 g of the functionalized polyphenylene ether was weighed in a 500 ml Erlenmeyer flask, and 200 ml of toluene was added and completely dissolved.

After adding 2 to 3 drops of an ethanol solution of phenolphthalein to this solution, 0.01 mol / l of a methanol solution of sodium methylate was added dropwise from a buret until the whole solution turned pink. The added amount of maleic anhydride was determined from the volume of the methanol solution of sodium methylate prepared. 2. Reduced viscosity of polyphenylene ether Polyphenylene ether was used as a chloroform solution of 0.5 g / 100 ml, and it was 0.43 dl / g as a result of measurement using an Ubbelohde viscometer at 30 ° C.

[0023]

Example 1 2 kg of polyphenylene ether having a reduced viscosity of 0.43 dl / g is dissolved in 20 kg of toluene at 55 ° C. Keep this solution at 55 ℃ and stir 50Kg
When methanol is added dropwise little by little, a white granular precipitate is produced, and a slurry is formed. The slurry is filtered through a glass filter, and the filtered white granular solid is dried under reduced pressure at 150 ° C. for 1 hour.

The polyphenylene ether powder (A) obtained by drying was passed through a 325-mesh sieve and divided into a powder (C) that passed through the sieve and a powder (B) that did not pass through the sieve. As a result of weighing each of them, (C) is 1.0
8 kg and (B) were 0.92 kg. Also, (C)
As a result of measuring the particle size distribution of using a laser granulometer,
It was found that 42 wt% of (C) were particles (D) having a particle size of 10 μm or less. Therefore, it was found that the ratio of (D) contained in (A) was 23%.

Then, 1143 g of (B) and 857 g of (C) were mixed and put into a reactor having a capacity of 10 L equipped with a stirrer. In this case, the proportion of (D) in the mixed powder of (B) and (C) is 18%. Further, a 10 L evaporator was connected to the reactor via a valve, and 1 Kg of maleic anhydride was charged in the evaporator. 205 ° C. oil was sent to the jacket of the reactor, the temperature change of the powder in the reactor was examined, and the time (t) until the temperature became stable and the temperature (T) at that time were measured. As a result, t = 32 min, T = 183
It was ℃.

Further, the evaporator was heated by a mantle heater so that the temperature of maleic anhydride in the evaporator was the same as the powder temperature. Next, nitrogen gas was sent to the evaporator at a flow rate of 1 L / min to start sending a mixed gas of maleic anhydride and nitrogen from the evaporator to the reactor. At the same time when this gas was started to be sent, the stirring device of the reactor was started to mix the powder and the gas in the reactor, and then the gas flow and stirring were continued for 60 minutes. The time during which the gas flow and stirring are continued corresponds to the reaction time. After the gas flow and stirring were stopped, the inside of the reactor was observed, and as a result, almost no powder adhered to the inner wall. The powder in the reactor was taken out and the amount of maleic anhydride added to the polyphenylene ether was measured. As a result, it was 0.45 wt%.

[0027]

Examples 2 to 5 The same procedure as in Example 1 was carried out except that the weight ratio of (B) and (C) was changed and the reaction time was changed. Table 1 shows the measurement results of t and T and the analysis results of the amount of maleic anhydride added to the functionalized polyphenylene ether. In these examples as well, the inside of the reactor after the reaction was observed, but almost no powder adhered to the inner wall.

[0028]

Comparative Examples 1 to 3 The same procedure as in Example 1 was carried out except that the weight ratio of (B) and (C) was changed. Table 1 shows the measurement results of t and T and the analysis results of the amount of maleic anhydride added to the functionalized polyphenylene ether. As a result of observing the state inside the reactor after the reaction in these examples, an adhesion layer of powder having a thickness of about 10 mm was found on the inner wall.

[0029]

[Table 1]

[0030]

Examples 6 to 8 Polyphenylene ether powder (A) was passed through a 100-mesh (JIS Z 8801) sieve and separated into passed (E) and non-passed (F). It can be estimated that (F) is a powder (G) having a particle size of 100 μm or more. As a result of weighing each, (E) is 38 kg,
(F) was 12 kg. The same reaction operation as in Example 1 was performed except that the mixing ratio of (E) and (F) was changed. The experimental results are shown in Table 2.

[0031]

[Table 2]

[0032]

INDUSTRIAL APPLICABILITY The present invention relates to a method for producing a functionalized polyphenylene ether having a high reaction rate and a high temperature raising rate, which has a high production efficiency, and has a small amount of powder scattering, resulting in a good operability.

Claims (5)

[Claims] 1. A polyphenylene ether (A) and (B)
At least one carbon-carbon double bond or triple bond in the molecule, and at least one functional group selected from the group consisting of a carboxyl group, an acyl oxide group, an imino group, an imide group, a hydroxyl group and a glycidyl group A method for producing a functionalized polyphenylene ether, characterized in that 20% by weight or less of polyphenylene ether particles having a particle diameter of 10 μm or less is used in the method of reacting one kind of functionalized compound at a temperature below the melting point of polyphenylene ether. 2. The method for producing a functionalized polyphenylene ether according to claim 1, wherein the polyphenylene ether having a particle size of 10 μm or less is 10% by weight or less. 3. The method for producing a functionalized polyphenylene ether according to claim 1, which comprises 30% by weight or more of polyphenylene ether having a particle size of 100 μm or more. 4. The method for producing a functionalized polyphenylene ether according to claim 1, wherein (B) is supplied in a gaseous state to the polyphenylene ether. 5. A functionalized polyphenylene ether produced by the production method according to claim 1.