JPH0885754A - Light-resistant polyphenylene ether resin composition and method for producing the same - Google Patents

Abstract

(57) [Summary] [Structure] Light resistance P containing 0.001 to 1 part by weight of alicyclic ketone (b) per 100 parts by weight of PPE (a).
PE resin composition. The resin composition comprises PPE (a) 100
A resin composition containing 0.1 to 30 parts by weight of an alicyclic ketone (b) is used in a kneader equipped with at least one vent port, and at least one vent port is kept under reduced pressure. It is manufactured by melt-kneading. [Effect] A PPE resin composition having a good balance between impact resistance and heat resistance can be obtained by removing the light stability inhibiting substance, improving the color tone and color tone change of the product.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a polyphenylene ether (hereinafter referred to as "PPE") resin composition having improved light resistance and a method for producing the same.

[0002]

2. Description of the Related Art PPE has excellent heat resistance, mechanical properties and electrical properties, and is used as an engineering resin for electric / electronic parts, automobile parts, household electric appliances / housing for office equipment, etc. It is poor in stability and has a problem of being significantly discolored when exposed to light indoors and outdoors.
For this reason, many literatures have been reported on the improvement of the light discoloration resistance of PPE resin compositions. In general, a compound such as a benzotriazole-based, cyanoacrylate-based or salicylate-based compound has been blended with PPE as a light stabilizer, but these compounds have a light discoloration resistance after high temperature molding. On the other hand, no sufficient suppression effect is seen.
The effects of addition of amine compounds are also described in some documents. For example, JP-A-63-2
Japanese Patent No. 51456 discloses the addition of a specific aromatic secondary amine for the purpose of improving the light discoloration resistance of PPE to light through glass, indoor lighting, etc. The working environment is poor when used for molding and molding, and the effect on light discoloration resistance is not sufficient.

Further, Japanese Patent Laid-Open No. 63-130657 discloses that the addition of α-hydroxyketone to PPE has the effect of suppressing discoloration of the resin composition during processing, but it is resistant to light discoloration. There is no description of the effect on. JP-A-2-265924 describes a method of adding a ketone to PPE and extracting and removing odorous components such as dihydrobenzofuran, dimethylcyclohexanone, dibutylamine and unsaturated amine. There is no description of effects on sex.

[0004]

SUMMARY OF THE INVENTION It is an object of the present invention to provide a PPE resin composition having improved light resistance, especially light resistance to discoloration, and a method for producing the same.

[0005]

The present invention provides a PPE (a)
Aliphatic ketone (b) 0.001 relative to 100 parts by weight
Is a light resistant PPE resin composition containing 1 part by weight.
Hereinafter, the present invention will be described in detail.

(1) PPE (a) The PPE (a) used in the present invention has the general formula (I)

[0007]

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(In the formula, Q ¹ represents a halogen atom, a primary or secondary alkyl group, an aryl group, a halo or aminoalkyl group, a hydrocarbon oxy group or a halohydrocarbon oxy group, and Q ² represents each. Hydrogen atom, halogen atom,
It represents a primary or secondary alkyl group, an aryl group, a haloalkyl group, a hydrocarbon oxy group or a halohydrocarbonoxy group. m represents an integer of 25 to 400), which is a homopolymer or a copolymer.

Preferred examples of the primary alkyl group for Q ¹ and Q ² include methyl, ethyl, n-propyl, n-butyl and n.
-Amyl, isoamyl, 2-methylbutyl, 2,3-dimethylbutyl, 2-, 3- or 4-methylpentyl or heptyl. Suitable examples of secondary alkyl groups are:
Isopropyl, sec-butyl or 1-ethylpropyl. In many cases, Q ¹ is an alkyl group or a phenyl group, especially an alkyl group having 1 to 4 carbon atoms, and Q ² is a hydrogen atom.

A specific example of PPE is poly (2,6-
Dimethyl-1,4-phenylene ether), poly (2,
6-diethyl-1,4-phenylene ether), poly (2,6-dipropyl-1,4-phenylene ether), poly (2-ethyl-6-methyl-1,4-phenylene ether), poly (2- Methyl-6-propyl-
1,4-phenylene ether), a copolymer of 2,6-dimethylphenol and 2,3,6-trimethylphenol, a copolymer of 2,6-dimethylphenol and 2,3,6-triethylphenol, Copolymer of 2,6-diethylphenol and 2,3,6-trimethylphenol, Copolymer of 2,6-dipropylphenol and 2,3,6-trimethylphenol, poly (2,6-dimethyl) Graft copolymer obtained by graft-polymerizing styrene to (1,4-phenylene ether), graft copolymer obtained by graft-polymerizing styrene to a copolymer of 2,6-dimethylphenol and 2,3,6-trimethylphenol Examples include coalescence.

A suitable homopolymer PPE (a) is, for example, poly (2,6-dimethyl-1,4-phenylene ether). Suitable copolymers include 2,6
A random copolymer of dimethylphenol and 2,3,6-trimethylphenol.

The molecular weight of PPE (a) is usually such that the intrinsic viscosity at 30 ° C. measured in chloroform is about 0.2 to 0.8 dl / g. The number average degree of polymerization is 25 to 400.

PPE (a) is usually produced by oxidative coupling of a phenol compound. Many catalyst systems are known for the oxidative coupling reaction of PPE. There is no particular limitation on the selection of the catalyst, and any known catalyst can be used. For example, those containing at least one heavy metal compound such as copper, manganese, and cobalt, usually in combination with various other substances (for example, US Pat. Nos. 4,042,056 and 3,3,3).
06,874, 3,306,875, 3,
365,422, 3,639,656, 3,642,699, 3,733,299, 3,838,102, 3,661,848,
Nos. 5,037,943, etc.).

(2) Alicyclic ketone (b) The alicyclic ketone (b) used in the present invention is represented by the following general formula (II)

[0015]

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[In the formula, each of Q ^a and Q ^b is a hydrogen atom, a hydroxyl group, an alkyl group having 1 to 20 carbon atoms, or a substituted or unsubstituted saturated or unsaturated cyclic hydrocarbon group having 5 to 8 carbon atoms. In the above, Q ^a and Q ^b may contain an oxygen atom, a nitrogen atom, a sulfur atom, or a halogen atom. n represents an integer of ^{2~10, -C (Q a) (} Q b) - can be represented by may Tsu different even in the same].

The solubility parameter of the alicyclic ketone (b) is preferably in the range of 7-12. Specific examples include cyclopentanone, cyclohexanone, cycloheptanone, cyclooctanone, 2,6-dimethylcyclohexanone,
2,6-diethylcyclohexanone, cyclononanone,
2- (1-cyclohexenyl) cyclohexanone etc. are mentioned. More preferably, the melt parameter is 8 to
Cyclohexanone, cyclopentanone, cycloheptanone, cyclooctanone and 2,6-dimethylcyclohexanone in the range of 10 are mentioned, and cyclohexanone is particularly preferable. These may be used alone or as a mixture.

(3) Composition Ratio of Constituents The composition ratio of the constituents in the light-resistant PPE resin composition of the present invention is 0.001 of alicyclic ketone (b) relative to 100 parts by weight of PPE (a). ~ 1 part by weight, preferably 0.0
01-0.5 parts by weight, more preferably 0.005-0.
1 part by weight. When the alicyclic ketone compound is less than 0.001 part by weight, the hue and light resistance of the composition are unsatisfactory,
If it exceeds 1 part by weight, the heat resistance and the appearance of the molded product are unsatisfactory.

(4) Additional components Other additional components can be added to the resin composition according to the present invention. For example, known thermoplastic resins, thermosetting resins, antioxidants, weather resistance improvers, nucleating agents, flame retardants,
Impact resistance improvers, plasticizers, fluidity improvers and the like,
Addition of organic / inorganic fillers and reinforcing agents, particularly glass fiber, mica, talc, wollastonite, potassium titanate, calcium carbonate, silica, etc., is effective in improving rigidity, heat resistance, dimensional accuracy and the like. For practical use, various colorants and dispersants thereof may be known ones.

(5) Method for producing composition and molding method To produce the light-resistant PPE resin composition of the present invention, PP is used.
The alicyclic ketone (b) 0.
1 to 30 parts by weight of the resin composition containing at least 1
In a kneader equipped with two vents, at least one vent is held under reduced pressure and melt-kneaded.

As the melt-kneader, a kneader generally used for thermoplastic resins can be applied. For example,
It may be a single-screw or multi-screw kneading extruder or the like, and may be a roll, a Banbury mixer or the like. It is preferably a kneader having one or more vent ports. Since it is preferable to maintain at least one vent port under a reduced pressure, at least a part of the resin in the kneader should be melted at the front stage of the vent port so that the resin can be sealed under reduced pressure. Further, since the resin in the kneader is kept in a molten state for a long time before reaching the vent port, the impact resistance decreases, so it is more preferable that the resin is melted immediately before reaching the vent port within a possible range. .

The vacuum device directly connected to the vent port may be selected in its capacity according to the degree of pressure reduction of the vent port, and its type and the like are arbitrary. Vent pressure is 200
Should be kept below mmHg. If it exceeds 200 mmHg, the heat resistance of the composition and the appearance of the molded product will be unsatisfactory.
It is preferably 100 mmHg or less, and particularly preferably 50
It is less than or equal to mmHg.

The order of kneading may be such that all the components may be kneaded at the same time, or a blended product preliminarily kneaded may be used for kneading, and the components may be sequentially fed from several feed ports of the extruder cylinder. May be fed and kneaded, but the compounding ratio is 0.1 to 30 parts by weight, preferably 0.1 to 25 parts by weight with respect to 100 parts by weight of PPE (a). , And more preferably 0.5 to 10 parts by weight.

The method for molding the light resistant PPE resin composition according to the present invention is not particularly limited,
Various molding methods generally used for thermoplastic resins, that is, various molding methods such as injection molding, hollow molding, extrusion molding, sheet molding, thermoforming, rotational molding, lamination molding, and press molding can be applied.

[0025]

EXAMPLES The present invention will be described in detail below with reference to examples.

Examples 1 to 4 and Comparative Examples 1 to 3 The components used are as follows. (A) PPE: poly (2,6-dimethyl-1,4-phenylene ether (manufactured by Nippon Polyether Co., Ltd.) Intrinsic viscosity measured in chloroform at 30 ° C .: 0.53 dl / g (b) Alicyclic ketone: Cyclohexanone (reagent grade) HIPS: High impact polystyrene (Mitsubishi Kasei Co., trade name: Dialex HT76) Polyethylene: Linear low density polyethylene (Mitsubishi Yuka F30F, using Ziegler catalyst, comonomer: butene) Oil: Paraffin oil (Made by Idemitsu Kosan Co., Ltd., product name: P
W-380)

The components shown in Table 1 were sufficiently mixed and stirred with a super mixer at the compounding ratio shown in the same table. Then, using a twin-screw type extruder (manufactured by Japan Steel Works, TEX44), this is set at a temperature of 180 to 230 ° C. and a screw rotation speed of 25.
Under a kneading condition of 0 to 350 rpm, a vent port installed downstream from the first kneading section was held at a pressure shown in Table 1 to melt-knead the composition, and then pelletized. In addition,
In Comparative Examples 1 and 2, the alicyclic ketone (b) was not used.

An in-line screw type injection molding machine (manufactured by Toshiba Kikai Seisakusho, IS
-90B type) with a cylinder temperature of 260 to 280
C., injection molding was performed at a mold cooling temperature of 60 to 80.degree. C. to prepare a test piece. Before injection molding, use a vacuum dryer until immediately before, at 0.1 mmHg and 80 ° C.
It was dried for 8 hours. The injection-molded test piece was placed in a desiccator immediately after molding, allowed to stand at 23 ° C. for 4 to 6 days, and then evaluated by the following method. The results are shown in Table 1.

(1) Flexural Modulus ISO R178-1974 Procedure 12 (JIS
K7203) and measured using an Instron tester. (2) Izod impact strength ISO R180-1969 (JIS K 7110)
According to the Izod impact strength with a notch, it measured using the Izod impact tester (made by Toyo Seiki Seisakusho KK). (3) Heat distortion temperature Using an HDT tester (manufactured by Toyo Seiki Seisakusho), JI
It was evaluated according to SK 7207 under a load of 18.6 kg.

(4) MFR ISO R1133-1981 (JIS K 721)
It measured using the MFR measuring machine according to 0). The measurement conditions are shown in Table 1. (5) Initial color tone (YI value) and color tone change (ΔYI value) Pellets of the melt-kneaded composition were heated at 250 ° C. for 10 minutes, 10 minutes.
And compression molded under the conditions of ^{~100kg / cm 2 6cm × 6cm ×} 2mm
Got a sheet of. These sheets are JISK 710
3 (Yellowness and yellowing test method for plastics) (initial color tone: YI value), and then accelerated exposure test (radiation) with a xenon weather meter (Suga Test Instruments Co., Ltd., trade name: XEL-3W). Illuminance 150 W / m ² , 63 ° C, humidity 50
%, No rainfall) was performed and the change in color tone over time was measured. The change in color tone is based on the color tone before exposure and the difference is determined by JIS
It was represented by ΔYI according to K 7103 [ΔYI = (initial yellowness)-(yellowing after exposure)]. The lightness and hue were measured with a hue / color difference meter (trade name: CR-200, manufactured by Minolta Camera Co., Ltd.).

[0031]

[Table 1]

[0032]

From the results of the above evaluation test, according to the present invention, the light stability inhibitor and the coloring volatile component are removed, the color tone and color change of the product are improved, and the impact resistance and heat resistance are improved. It can be seen that a light-resistant PPE resin composition having an excellent balance of is obtained. Therefore, its use is wide and it can be an industrially useful material.

Claims (2)

[Claims] 1. A polyphenylene ether resin composition comprising the following components (a) and (b) in the following compounding ratio. (A) Polyphenylene ether 100 parts by weight (b) Alicyclic ketone 0.001-1 part by weight 2. A resin composition containing 0.1 to 30 parts by weight of an alicyclic ketone with respect to 100 parts by weight of polyphenylene ether, in a kneader equipped with at least one vent port, at least one vent port is provided. The method for producing a polyphenylene ether resin composition according to claim 1, wherein the kneading is carried out while maintaining a reduced pressure.