JPH08183902A - Polyphenylene ether resin composition - Google Patents

Abstract

PURPOSE: To obtain the composition having improved dimensional accuracy and fluidity without impairing impact resistance of a molded article by blending a PPE having a low intrinsic viscosity with glass fibers and lamellar fillers within the specific ranges. CONSTITUTION: This composition comprises 100 pts.wt. of the sum of (A) 10-100 pts.wt. of a polyphenylene ether (PPE for short) having 0.25-0.40dl/g intrinsic viscosity [η] and (B) 90-0 pts.wt. of an aromatic vinyl-based resin, (C) 5-150 pts.wt. of glass fibers and (D) 5-150pts.wt. of a lamellar filler. The component A, for example, is shown by the formula (Q<1> to Q<4> are each H, a halogen, an alkyl or a monofunctional substituent group; (q) is a degree of polymerization). To be concrete, a poly(2,6-dimethyl-1,4-phenylene)ether is used as the component A. Glass fibers having 8-15μm diameter and 15-35 aspect ratio are used as the component C and a scaly filler having has 20-300μm diameter, 1-8μm thickness and 10-100 scaly shape is used as the component D.

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 composition, and more particularly to a polyphenylene ether resin composition having improved dimensional accuracy and fluidity without impairing impact resistance of molded articles.

[0002]

2. Description of the Related Art Polyphenylene ether resin (hereinafter referred to as P
PE is sometimes abbreviated as PE) is a thermoplastic resin having excellent heat resistance, toughness, hydrolysis stability, dimensional stability, and electrical characteristics. Since PPE alone has a high melt viscosity, it is often used as a blend with an aromatic vinyl resin having excellent fluidity. The blending ratio of PPE and aromatic vinyl resin is blended at a desired ratio, but if the ratio of PPE is high, the fluidity becomes insufficient, and conversely, if the ratio of aromatic vinyl resin is high, the excellent PPE has. Also, the heat resistance is impaired, so the compounding ratio is set and used while balancing both properties depending on the application.

As a means for improving the flatness and dimensional accuracy of warpage of a molded product, there is a method of filling a plate filler such as mica or glass flakes in a high ratio. Thereby, a molded product with high dimensional accuracy can be obtained, but the fluidity of the composition during molding is low, and it does not satisfy recent large-sized thin-wall molding.

On the other hand, the size of a molding machine (generally determined by the mold clamping pressure) is made small in order to increase the size and thickness of molded products in recent years, or for the purpose of improving production efficiency and shortening the molding cycle. There is a strong demand for improvement in the fluidity of the resin for the reason that it can be made into a resin.

As a method of improving the fluidity, a method of increasing the compounding ratio of the aromatic vinyl resin to the PPE resin has been adopted as described above, but it has a disadvantage of sacrificing heat resistance. It was

Japanese Unexamined Patent Publication (Kokai) No. 3-229756 discloses that in a glass fiber reinforced PPE resin composition, the fluidity is improved by using PPE having a low intrinsic viscosity. However, the resin composition often has insufficient dimensional accuracy such as flatness or warpage of a molded product. Therefore, there is a drawback in that it cannot be used as a precision component for recent electric and electronic devices requiring high precision.

Attempts have been made to improve the fluidity of a PPE resin composition containing a plate-like reinforcing material by using PPE having a low intrinsic viscosity (JP-A-6-1726).
No. 35). However, the resin composition has a drawback in that mechanical strength, particularly impact resistance is significantly lowered. For this reason, in the production of a large-sized thin-walled molded product, there is a big problem that the molded product is cracked when it is released from the mold, or the molded product is cracked by an impact such as a drop after molding. .

[0008]

SUMMARY OF THE INVENTION It is an object of the present invention to provide a polyphenylene ether resin composition having improved dimensional accuracy and fluidity without impairing the impact resistance of molded articles.

[0009]

Means for Solving the Problems As a result of intensive investigations by the present inventors, as a result of blending glass fiber and a plate-like filler into PPE having a low intrinsic viscosity within the following predetermined range,
The inventors have found that the above problems can be solved, and further that the dimensional accuracy is further improved by using the following predetermined PPE having an intrinsic viscosity lower than that of the conventional PPE, and have completed the present invention.

That is, according to the present invention, (1) (A) the intrinsic viscosity [η] is 0.25 to 0.40 dl.
/ C polyphenylene ether resin 10 to 100 parts by weight and (B) aromatic vinyl resin 90 to 0 parts by weight to a total of 100 parts by weight, (C) glass fiber 5 to 15
It is a resin composition containing 0 part by weight and (D) a plate-like filler in an amount of 5 to 150 parts by weight.

In a preferred embodiment, the resin composition according to the above (1), which comprises (2) (C) 5 to 70 parts by weight of glass fiber and (D) 5 to 70 parts by weight of plate filler, (3) (C). Glass fiber 10 to 50 parts by weight and (D)
Examples include the resin composition described in (1) above containing 10 to 50 parts by weight of a plate-like filler.

In the resin composition of the present invention, the component (A)
The compounding ratio of PPE and the component (B) aromatic vinyl resin is
(A) 10 to 100 parts by weight, (B) 90 to 0 parts by weight, preferably (A) 20 to 90 parts by weight,
(B) 80 to 10 parts by weight, particularly preferably (A) 30 to
The amount of (B) is 70 to 20 parts by weight with respect to 80 parts by weight. If the component (A) is less than the lower limit and the component (B) exceeds the upper limit, the excellent heat resistance of PPE cannot be exhibited, which is not preferable. The lower limit of the amount of component (C) is 5 parts by weight based on 100 parts by weight of components (A) and (B).
It is preferably 10 parts by weight, and the upper limit is 150 parts by weight, preferably 70 parts by weight, particularly preferably 50 parts by weight. If it is less than the above lower limit, the impact strength is lowered, and if it exceeds the above upper limit, the fluidity is lowered and the dimensional accuracy is deteriorated, which is not preferable. Further, the blending amount of the component (D) is the same as that of the component (A).
The lower limit is 5 parts by weight, preferably 10 parts by weight, and the upper limit is 150 parts by weight, preferably 70 parts by weight, and particularly preferably 50 parts by weight, with respect to 100 parts by weight in total of (B). If it is less than the above lower limit, the effect of improving dimensional accuracy (warpage) is small, and if it exceeds the above upper limit, fluidity and impact strength are lowered, which is not preferable.

The component (A) polyphenylene ether resin used in the present invention has an intrinsic viscosity [η] of 0.25.
~ 0.40 dl / g, preferably 0.25 to 0.35d
1 / g, particularly preferably in the range of 0.27 to 0.33 dl / g. By using the polyphenylene ether resin in the above range, the dimensional accuracy of the molded product can be improved. If it is less than the above range, the impact strength of the molded product is largely lowered, and the value as a practical product is impaired. Exceeding the above range causes a decrease in the fluidity of the resin composition,
In particular, it becomes difficult to form a large-sized thin-walled molded product. Here, the intrinsic viscosity [η] is a value measured in a chloroform solution at 25 ° C.

In the present invention, as the component (A) polyphenylene ether resin, known ones can be used. The polyphenylene ether resin is, for example, a general formula:

[0015]

Embedded image (Wherein Q ¹ , Q ² , Q ³ and Q ⁴ are independently
A hydrogen atom, a halogen atom, an alkyl group, an alkoxy group, or a haloalkyl group or a haloalkoxy group having at least two carbon atoms between the halogen atom and the phenyl ring, which does not contain a tertiary α-carbon. Represents a monovalent substituent group, and q is an integer representing the degree of polymerization), and is a general term for polymers represented by the above general formula. It may be a combined copolymer.

The method for producing PPE is not particularly limited. For example, US Pat. No. 3,306,874 and US Pat.
It can be prepared by the reaction of phenols according to the procedures described in 257,357 and 3,257,358. These phenols include 2,6-dimethylphenol, 2,6-diethylphenol, 2,6-dibutylphenol, 2,6-dilaurylphenol, 2,6-dipropylphenol, 2,6-diphenylphenol, 2-methyl-6-
Ethylphenol, 2-methyl-6-cyclohexylphenol, 2-methyl-6-tolylphenol, 2-methyl-6-methoxyphenol, 2-methyl-6-butylphenol, 2,
Includes, but is not limited to, 6-dimethoxyphenol, 2,3,6-trimethylphenol, 2,3,5,6-tetramethylphenol and 2,6-diethoxyphenol. Each of these may be reacted alone to give the corresponding homopolymer or with another phenol to give the corresponding copolymer having different units included in the above formula.

In a preferred embodiment, Q ¹ and Q ² are alkyl groups having 1 to 4 carbon atoms, and Q ³ and Q ⁴ are hydrogen atoms or alkyl groups having 1 to 4 carbon atoms. For example, poly (2,6-dimethyl-1,4-phenylene) ether, poly (2,6-diethyl-1,4-phenylene) ether, poly (2-methyl-6-ethyl-1,1) 4-phenylene) ether, poly (2-methyl-6-propyl-1,4)
-Phenylene) ether, poly (2,6-dipropyl-1,4
-Phenylene) ether, poly (2-ethyl-6-propyl-1,4-phenylene) ether and the like. The PPE copolymer may be an alkyltrisubstituted phenol in the polyphenylene ether repeating unit, such as
Examples thereof include a copolymer partially containing 2,3,6-trimethylphenol. Further, it may be a copolymer obtained by grafting a styrene compound on these PPE.
The styrene compound-grafted polyphenylene ether is a copolymer obtained by graft-polymerizing styrene compounds such as styrene, α-methylstyrene, vinyltoluene and chlorostyrene to the above PPE. The component (B) aromatic vinyl resin optionally used in the present invention is also known per se and represented by the general formula

[0018]

Embedded image (In the formula, R represents hydrogen or an alkyl group having 1 to 4 carbon atoms, Z represents a halogen or a substituent which is an alkyl group having 1 to 4 carbon atoms, and p is an integer of 0 to 5). It must have at least 25% by weight or more in the polymer of repeating structural units derived from the indicated aromatic vinyl compounds.

Examples of the aromatic vinyl resin include homopolymers of styrene and its derivatives, and polybutadiene, polyisoprene, butyl rubber, EPD.
M rubbers, ethylene-propylene copolymers, natural rubbers, polysulfide rubbers, polyurethane rubbers, epichlorohydrin-modified styrene polymers modified by the mixing or interaction of natural or synthetic elastomeric substances, and also styrene-containing copolymers. Polymers such as styrene-acrylonitrile copolymer (SAN), styrene-butadiene copolymer, styrene-maleic anhydride copolymer, styrene-acrylonitrile-butadiene terpolymer (A
BS), poly-α-methyl-styrene, a copolymer of ethylvinylbenzene and divinylbenzene, and the like. Further preferred resins for the present invention are polystyrene homopolymers, or polybutadiene rubber or EP.
3 to 30% by weight of DM rubber, preferably 4 to 12% by weight
It is a rubber-modified polystyrene mixed with or grafted with it.

The component (C) glass fiber is known per se, and various glass fibers such as commercially available E glass, C glass, S glass and A glass can be used. The diameter of the glass fibers is preferably 5 to 20 microns, particularly preferably 8 to
It is 15 microns. When the amount is less than the above lower limit, it becomes difficult to handle the glass fiber when heat kneading with PPE, and the dispersion of the glass fiber in the resin becomes poor. When it exceeds the above range, the impact strength and the rigidity decrease. The average fiber length after kneading with the resin is preferably 150 to 500 μm, particularly preferably 200 to 400 μm, and the above range is preferable in terms of impact strength and fluidity. The aspect ratio (ratio of diameter to length) is preferably 10 to 40, particularly preferably 15 to
35. If it is less than the above lower limit, the strength and rigidity are lowered, and if it exceeds the above range, the fluidity and the dimensional accuracy are deteriorated. As the glass fiber, for example, chopped strand, roving, etc. can be preferably used. Further, the adhesive glass fiber described in U.S. Pat. No. 43,289 is preferably used. The glass fibers typically have an affinity for the resin in the thermoplastic resin matrix.

The component (D) plate-like filler is also known per se and is not particularly limited. For example, kaolinite, talc, sericite, muscovite (mascobite)
And mica such as phlogopite, chlorite,
Examples include layered clay minerals such as montmorillonite and halosite, glass flakes, artificial plate-like fillers such as metal plate particles (for example, gold), and the like. The plate-like filler preferably has a diameter (average length in the spreading direction) of 5 to 500 μm.
m, particularly preferably 20 to 300 μm, the thickness is preferably 0.1 to 10 μm, particularly preferably 1 to 8 μm, and the aspect ratio (ratio of diameter to thickness) is preferably 3 or more, particularly preferably 10 to 100. Scale-like ones are preferred. If the aspect ratio is less than the above lower limit, the reinforcing effect is small and the strength and rigidity cannot be improved.

The above-mentioned (C) glass fiber and (D) plate-like filler can be used as they are, or of course, ordinary surface-treating agents, for example, silane coupling agents such as epoxysilane, aminosilane, vinylsilane, mercaptosilane and chlorosilane. It can also be used after being surface-treated with an agent, a titanate coupling agent, an aluminum coupling agent, or the like.

Further, in the resin composition of the present invention, in addition to the above-mentioned components, various additives known to those skilled in the art, for example, reinforcing materials and fillers such as pigments and dyes, metal fibers and carbon fibers,
A heat stabilizer, an antioxidant, an ultraviolet absorber, a light stabilizer, a lubricant, a plasticizer, an antistatic agent, a flame retardant and the like can be added.

In producing the polyphenylene ether resin composition of the present invention, the respective components can be mixed by a conventionally known method. For example, pellet each component,
A method of dispersing and mixing in the form of powder or fine pieces with a high-speed mixer represented by a turnbull mixer or a Henschel mixer, and then melt-kneading with a uniaxial or multiaxial extruder, a Banbury mixer, a roll or the like is appropriately selected.

The resin composition of the present invention has a very good balance of impact resistance, dimensional accuracy and fluidity of a molded article, and further has good fluidity at the time of molding. It can be widely used as a material for large-sized, thin-walled precision molded products in the field of electric equipment parts and the like.

Hereinafter, the present invention will be described in more detail with reference to Examples and Comparative Examples, but the present invention is not limited thereto.

[0027]

EXAMPLES The following substances were used in the following examples and comparative examples. <Component (A): Polyphenylene ether resin (PPE)
> Poly (2,6-) with an intrinsic viscosity [η] of 0.30 dl / g
Dimethyl-1,4-phenylene) ether <Component (B): aromatic vinyl resin> General-purpose polystyrene (GPPS) (CR-3500, trademark, manufactured by Dainippon Ink and Chemicals, Inc.) <Component (C): glass Fiber (GF)> average diameter 13 μm,
The average length was 3 mm, CS-3PE-291, trademark, manufactured by Nitto Boseki Co., Ltd., and after kneading, the particles were dispersed with an average length of about 300 μm. <Component (D): Plate-shaped filler> Mica (average diameter 55 μm
m, average aspect ratio 55, S-200HG, trademark, manufactured by Repco Co., Ltd. <Optional component: flame retardant> triphenyl phosphate (TP
P, manufactured by Daihachi Chemical Co., Ltd.) and resorcinol tetraphenyldiphosphate (RDP) (CR733S, trademark, manufactured by Daihachi Chemical Co., Ltd.) were used. <Comparative component: polyphenylene ether resin (PPE-
C)> poly (2, with an intrinsic viscosity [η] of 0.46 dl / g
6-dimethyl-1,4-phenylene) ether

[0028]

Examples 1 to 6 and Comparative Examples 1 to 15 The amounts (parts by weight) of each component shown in Tables 1 and 2 were used in a 53 mmφ twin-screw extruder, the cylinder temperature was set to 300 ° C., and the screw rotation speed was set to 1
The mixture was melt-kneaded at 50 rpm and extruded at a discharge rate of 90 kg / hour to form pellets. The resulting pellets are 4 at 80 ° C
After drying for an hour, various test pieces were prepared with a T-80 type injection molding machine manufactured by Toyo Seiki at a cylinder set temperature of 280 ° C. and a mold temperature of 60 ° C., and subjected to an evaluation test.

The results of these evaluations are shown in Tables 1 and 2.
These properties were measured as follows. <Notched Izod Impact Strength (NII)> ASTM
According to D256, the Izod impact strength with 1/8 inch notch was measured. <Tensile Strength (TS)> It was measured according to ASTM D638. <Bending characteristics (bending strength FS, bending elastic modulus FM)> AST
It measured according to MD790. <Heat Distortion Temperature (HDT)> According to ASTM D648, the load was measured at 18.6 kg / cm ² . <Melt Index (MI)> ASTM D1238
Pre-dry the pellets at 80 ° C for 4 hours according to
The measurement was performed at 00 ° C. under a load of 5 kg and an orifice diameter of 2.09 mmφ. <Sledding> 100mmφ with side gate, thickness 1.6
A mm disk was created. A three-dimensional measuring device is used to measure the distance between each defined point on the plane and the virtual plane, and the difference between the maximum value and the minimum value is expressed as a warp (mm). <Flame Retardancy (UL94)> Underwriters Laboratories Corporation In accordance with the test method shown in the Combustion Test for Classifying Bulletin 94 Materials (referred to as UL94), using 5 test pieces of 1.6 mm thickness did. The operation of measuring the combustion time (time until extinction) after 10 seconds of indirect flame on one test piece was repeated twice.

[0030]

[Table 1]

[0031]

[Table 2] Examples 1 and 2 are results with the resin composition of the present invention. The molded product had high impact strength, and the dimensional accuracy and fluidity were very excellent.

On the other hand, Comparative Example 1 does not contain the component (D) mica. The warpage was large and the dimensional stability was lacking. Comparative Example 2 is one in which the component (C) glass fiber was not mixed. The impact strength was low. Comparative Example 3
Nos. 4 and 5 are those in which PPE having an intrinsic viscosity exceeding the range of the present invention was used in place of the component (A). All had a low melt index and poor flowability. Further, the dimensional accuracy was poor as compared with Examples 1 and 2, respectively. In Comparative Example 5, PPE having an intrinsic viscosity exceeding the range of the present invention was used in place of the component (A), and the component (C) was not blended. The dimensional stability was almost the same as in Examples 1 and 2, but the impact strength and fluidity were low.

Examples 3 and 4 are obtained by decreasing the compounding amount of the component (A) and increasing the compounding amount of the component (B) within the scope of the present invention, as compared with Examples 1 and 2, respectively. Comparative Examples 6 and 7 were obtained by not adding the component (D) and the component (C) to Examples 3 and 4, respectively, and Comparative Examples 8 and 9 were compared with Examples 3 and 4, respectively. What uses PPE whose intrinsic viscosity exceeds the range of the present invention in place of the component (A), Comparative Example 10 uses PPE whose intrinsic viscosity exceeds the range of the present invention in place of the component (A), Moreover, the component (C) was not added. Comparative Examples 1 to 5 above
Similarly to Comparative Example 6, the warpage was large, Comparative Example 7 had a low impact strength, Comparative Examples 8 and 9 had a small melt index, and the dimensional accuracy and fluidity of the molded product were poor.
Further, Comparative Example 10 had almost the same dimensional stability as Examples 3 and 4, but the impact strength and fluidity were low.

In Examples 5 and 6, the compounding amounts of the components (C) and (D) were increased, respectively. Comparative Examples 11 and 12 are the same as Examples 5 and 6, respectively, except that the component (D) and the component (C) were not blended, and Comparative Examples 13 and 14 were used.
In contrast to Examples 5 and 6, respectively, PPE was used in place of the component (A), and the intrinsic viscosity exceeded the range of the present invention. In Comparative Example 15, the intrinsic viscosity was changed in place of the component (A). Uses PPE beyond the scope of the present invention, and component (C)
It is the one that was not blended. Comparative Example 11 has large warpage, Comparative Example 12 has low impact strength, and Comparative Examples 13 and 14
All had a small melt index and a large warpage, and Comparative Example 15 had a low impact strength and a small melt index.

[0035]

The object of the present invention is to provide a polyphenylene ether resin composition having improved dimensional accuracy and fluidity without impairing the impact resistance of the molded product. Therefore, the molded product does not crack at the time of releasing the mold or dropping.

Claims (1)

[Claims] 1. An (A) intrinsic viscosity [η] is 0.25 to 0.4.
0 dl / g polyphenylene ether resin 10 to 10
0 parts by weight and (B) aromatic vinyl-based resin 90 to 0 parts by weight to a total of 100 parts by weight, (C) glass fiber 5
~ 150 parts by weight and (D) a plate-like filler 5 to 150 parts by weight.