JP3197373B2 - Polyphenylene ether powder - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a polyphenylene ether resin powder having a particle size with good powder handling properties.

[0002]

2. Description of the Related Art In general, polyphenylene ether resins are prepared by oxidative polymerization of phenols in an organic solvent using a catalyst comprising a combination of a metal salt and various amines (JP-B-42-3195, JP-B-45). −2355
No. 5, JP-A-64-33131 and JP-A-52-33131.
No. -897) is well known. The recovery of the polyphenylene ether resin powder from the polymer solution polymerized by these methods is generally performed by contacting the polyphenylene ether resin with a poor solvent for the polyphenylene ether resin such as methanol. At this time, the precipitated polyphenylene ether resin particles include extremely fine particles and extremely large particles. This means that the precipitated polyphenylene ether resin particles have an increased filtration time in the filtration step, a problem of poor transport due to scattering or clogging in the drying step and the transportation step, or polyphenylene ether supplied from the hopper during extrusion granulation. Poor entrapment of the resin powder causes many troubles. In the operation of polyphenylene ether resin powder containing such fine particles and extremely large particles,
It may be solved by combining devices such as a vacuum hopper and a vacuum conveyor. However, there are economic disadvantages caused by using an expensive machine, and there is a problem that operation is complicated.

As disclosed in Japanese Patent Publication No. 45-587, a poor solvent for a polyphenylene ether resin is brought into contact with a polymer solution containing the polyphenylene ether resin to precipitate the polymer. It has been already known that the conditions for precipitating the polymer greatly affect the particle size of the polyphenylene ether resin.
Japanese Patent Publication No. 55-17775 discloses a method of enlarging the particle diameter of a polyphenylene ether resin powder by performing a heat treatment in an aqueous dispersion of a polyphenylene ether resin powder containing an organic solvent.

Japanese Patent Publication No. 23696/1985 discloses that a non-solvent composition of a polyphenylene ether resin is added to a polymer solution containing the polyphenylene ether resin so as to form a two-phase system with the solvent, and the precipitated particles are enlarged. Is clearly specified. Japanese Patent Application Laid-Open No. 63-6024 discloses a method in which polyphenylene ether is dispersed in an aqueous solution of a phosphoric acid compound into fine particles of a wet solid particle containing a solvent or a polyphenylene ether solution dissolved in a solvent. The method of obtaining the body is specified.

[0005] However, in all of the above-mentioned inventions, there is no description about volatile components in the powder and granules. Japanese Patent Publication No. 59-15352 discloses an invention relating to volatile components in powders. According to this publication, a resin composition having good crack resistance can be obtained by suppressing volatile components having a molecular weight of 320 or less to 5000 ppm or less in a composition comprising a polyphenylene ether resin and a rubber-reinforced styrene-based polymer. It is specified.

[0006] For this purpose, it is desired that the polyphenylene ether resin particles have a reduced volatile content and good handleability.

[0007]

SUMMARY OF THE INVENTION It is an object of the present invention to provide a polyphenylene ether resin powder having excellent powder handling properties and capable of obtaining a good molded product.

[0008]

Means for Solving the Problems The present inventors have made intensive studies to achieve the above object, and as a result, have arrived at the present invention. That is, the present invention is state, and are the weight fraction of the smaller particles a particle diameter 105μ is 30% or less, and a molecular weight of 320 or less volatile growth
Min content is polyphenylene ether resin powder or granular material, characterized in der Rukoto 1.5% or less.

The polyphenylene ether resin used in the present invention is represented by the following general formula (1):

[0010]

Embedded image

Wherein R1, R2, R3, R4, R5
R6 is a monovalent residue such as an alkyl group having 1 to 4 carbon atoms, an aryl group, halogen, and hydrogen, and R5 and R6 are not simultaneously hydrogen. ) Is a repeating unit, and a homopolymer or a copolymer in which the structural units are represented by the above formulas [a] and [b] can be used. Representative examples of the homopolymer of the polyphenylene ether resin include poly (2,6-dimethyl-
1,4-phenylene ether, poly (2-methyl-6-
Ethyl 1,4-phenylene) ether, poly (2,6-
Diethyl-1,4-phenylene) ether, poly (2-
Ethyl-6-n-propyl-1,4-phenylene) ether, poly (2,6-di-n-propyl-1,4-phenylene) ether, poly (2-methyl-6-n-butyl-1, 4-phenylene) ether, poly (2-ethyl-
6-isopropyl-1,4-phenylene) ether, poly (2-methyl-6-chloroethyl-1,4-phenylene) ether, poly (2-methyl-6-hydroxyethyl-1,4-phenylene) ether, poly Homopolymers such as (2-methyl-6-chloroethyl-1,4-phenylene) ether are exemplified.

The polyphenylene ether copolymer is 2,2
Copolymer of 6-dimethylphenol and 2,3,6-trimethylphenol or copolymer of o-cresol or 2,3,6-trimethylphenol and o-cresol
Includes polyphenylene ether copolymers having a polyphenylene ether structure as a main component, such as copolymers with cresol.

In the polyphenylene ether resin of the present invention, various other phenylene ether units which have been proposed to be allowed to exist in the polyphenylene ether resin so far as they do not contradict the gist of the present invention are used. It may be included as a partial structure. Japanese Patent Application No. 63-1 / 1988 discloses an example of a proposal for coexistence in a small amount.
2- (dialkylaminomethyl) -6-methylphenylene ether unit and 2- (N-alkyl-N-phenylaminomethyl) -6-methyl described in JP-A-2698 and JP-A-63-301222. And phenylene ether units.

The polyphenylene ether resin also includes a resin in which a small amount of diphenoquinone or the like is bonded in the main chain.
Further, for example, polyphenylene ether modified with a compound having a carbon-carbon double bond described in JP-A-2-276823, JP-A-63-108059, JP-A-59-59724 and the like. Including.

The polyphenylene ether resin used in the present invention has a number average molecular weight of 1,000 to 10
It is 0000. The preferred range is about 6,000
~ 60,000. The number average molecular weight in the present invention is a number average molecular weight in terms of polystyrene obtained by gel permeation chromatography using a standard polystyrene calibration curve.

In the present invention, the preferred weight fraction of particles having a particle size of 105 μ or less is 0 to 30%, more preferably 0 to 20%.
%. When the weight fraction of particles having a particle size of 105 μ or less is more than 30%, the powder is scattered frequently, and poor extrusion of the polyphenylene ether resin powder supplied from the hopper occurs during extrusion granulation. When producing a composition with a resin or the like, a good composition cannot be produced stably.

The molecular weight contained in the granular material of the present invention is 3
Volatile components of 20 or less are polymerization solvents, residual monomers and oligomers contained in polyphenylene ether. When polyphenylene ether is formed into a composition with a rubber-reinforced styrene-based resin, the volatile component and the residual monomers, oligomers, and polymerization solvents contained in the rubber-reinforced styrene-based resin are contained. During the production, a volatile component generated by thermal decomposition of the styrene-based polymer is contained in the composition.

Specific examples thereof include styrene monomer, ethylbenzene, toluene, xylene, tetrahydrofuran, pyridine, styrene dimer and styrene trimer. Among them, volatile components that easily remain in the composition include styrene monomer, styrene dimer, styrene trimer, ethylbenzene, toluene, xylene, and the like. , Xylene and the like. More specifically, the volatile component contained in the polyphenylene ether powder according to the present invention, and further the volatile component contained in the composition using the same, the polyphenylene ether powder and It can be measured by gas chromatography (detector FID) using a solution in which the resin composition is dissolved in chloroform.

Components such as styrene monomer, xylene, and ethylbenzene are used as column packing materials such as PEG-20M,
At 115 ° C. with 25%, styrene dimer and styrene trimer are used as column packings with silicon OV-1.
It can be measured at 190 ° C. and 260 ° C. respectively using 7, 3%. The components of the retention time before the styrene trimer are summed up as volatile components.

When the volatile component having a molecular weight of 320 or less contained in the resin composition is 5000 ppm or less, a molded article having good crack resistance can be obtained. In order to stably produce a composition suppressed to 5000 ppm or less, the volatile component 1.5% contained in the polyphenylene ether powder in advance is required.
% Is preferably reduced, more preferably 1.0% or less, particularly preferably 0.8% or less.

When the volatile component exceeds 1.5%, for example, in forming a composition with a styrenic resin, 60 Torr
The volatile component content of the composition is 50
It is difficult to stably produce it at a concentration of not more than 00 ppm, and it is difficult to obtain a molded article having good crack resistance. Generally, it is difficult to achieve both enlargement of the particle diameter and reduction of the volatile content. Good handling,
Moreover, polyphenylene ether particles having a reduced volatile content have been desired, but the present invention is an excellent polyphenylene ether particle satisfying both of them.

[0022]

EXAMPLES The present invention will be specifically described below with reference to examples, but the present invention is not limited to the following examples.
The amount of volatile components in the examples was quantified using gas chromatography (detector FID). Components such as styrene monomer, ethylbenzene, and xylene were quantified at 115 ° C. using a column filler PEG-20M, 25% (carrier Chromosolve W, column length 3 m), and styrene dimer and styrene trimer were used as column filler silicon OV. -17, 3% (Carrier Chromosolve W, column length 3
m) at 190 ° C. and 260 ° C., respectively. The components having a retention time before the styrene trimer were totaled to determine the amount of volatile components in the resin composition.

[0023]

Embodiment 1 A method described in US Pat. No. 3,308,874 is described.
Touch the complex of cuprous salt and amine according to the example.
Oxidative polymerization of 2,6-xylenol as a medium
An intrinsic viscosity (in chloroform, 30 ° C.) of 0.553 and a volatile matter content of 3.15% by being precipitated in a solvent . 1
Poly (2,6) having a content of particles of 73.5% or less
-Dimethyl-1,4-phenylene) ether (PPE)
I got Which using a twin screw extruder (PCM-30 mm?, Manufactured by Ikegai Steel Inc.), set at a cylinder temperature of 205 ° C., out press remove the tip of the die, to obtain a white powdery grains.

The obtained granules are sieved to a particle size of 10
The weight fraction of particles having a particle size of 5 μ or less is measured, the powder is dropped in a tube using a powder tester (manufactured by Hosokawa Micron Corporation), and the degree of dispersion is determined by examining the amount of powder remaining on a glass plate placed below. Was measured. In addition, the volatile content was measured. Table 1 shows the results.

[0025]

Example 2 Instead of the cylinder temperature condition of 205 ° C.,
Example 1 was repeated except that the temperature was set to 200 ° C. Table 1 shows the results.

[0026]

Comparative Example 1 The PPE powder used in Example 1 was sieved without passing through an extruder, and the weight fraction of particles having a particle size of 105 μm or less was measured. The degree of dispersion was measured with a powder tester (manufactured by Hosokawa Micron Corporation). Table 1 shows the results.

[0027]

Example 3 50 parts of the polyphenylene ether resin granules obtained in Example 1 and 50 parts of rubber-reinforced polystyrene (Asahi Kasei polystyrene 490) were mixed in a blender, and a twin-screw extruder (PCM-30 mmφ, Ikegai) was used. Steel Co., Ltd.
280 ° C., screw speed 130 r. p. m. The mixture was melt-kneaded at a discharge rate of 10.0 kg / hr and a pressure of 60 Torr to obtain a pellet-shaped resin composition, and the volatile components were quantified.

Under these conditions, the maximum discharge rate when the feed rate was increased was 14.5 kg / hr. Further, a 1/8 inch dumbbell test piece was prepared from the resin composition at 290 ° C. After storage in a thermostatic chamber at 23 ° C. and 50% RH for 50 days after molding, it was determined whether or not cracks had occurred at the tip of the dumbbell test piece. Table 2 shows the results.

[0029]

Example 4 The same operation as in Example 3 was repeated except that the polyphenylene ether resin particles of Comparative Example 2 were used instead of the polyphenylene ether resin particles obtained in Example 1. Table 2 shows the results. Under these conditions, the maximum discharge rate when the feed rate is increased is 14.1 kg / hr.
Met.

[0030]

Comparative Example 2 The same operation as in Example 3 was repeated except that the polyphenylene ether resin particles of Comparative Example 1 were used instead of the polyphenylene ether resin particles obtained in Example 1. Table 2 shows the results. Under these conditions, the maximum discharge rate when the feed rate is increased is 11.2 kg / hr.
In Examples in which the weight fraction of particles having a particle size of 105 μm or less was reduced to 30% or less, better extruder biteability was exhibited.

[0031]

[Table 1]

[0032]

[Table 2]

[0033]

According to the polyphenylene ether powder of the present invention, the handleability is remarkably improved, and the occurrence of cracks in a molded article when a composition is formed using the same is suppressed.

Claims (1)

(57) [Claims] 1. The method according to claim 1, wherein the weight fraction of the particles having a particle size of 105 μm or less is 3
0% Ri der less, and the volatile components having a molecular weight of 320 or less
Polyphenylene ether resin powder or granular material content is characterized der Rukoto 1.5% or less.