JPH06157896A - Inorganic-filler-reinforced resin composition - Google Patents

Abstract

PURPOSE:To obtain a molding material good in rigidity, impact resistance, dimensional accuracy, appearance, etc. CONSTITUTION:This inorg. filler-reinforced resin compsn. comprises 100 pts.wt. resin compsn. comprising a polyphenylene ether resin and a polystyrenic resin and 10-200 pts.wt. inorg. filler comprising a fibrous filler and a scaly filler.

Description

Detailed Description of the Invention

[0001]

FIELD OF THE INVENTION The present invention relates to a novel inorganic filler-reinforced resin composition. More specifically, the present invention is
The present invention relates to an inorganic filler-reinforced polyphenylene ether resin composition excellent in rigidity, impact resistance, dimensional accuracy and appearance.

[0002]

2. Description of the Related Art A resin composition comprising a polyphenylene ether resin and a polystyrene resin is excellent in mechanical properties, thermal properties, electrical properties, etc. As a material, the demand for the resin composition is remarkably increasing, and the required performance of the resin composition tends to be more and more diversified accordingly. For example, since it is used for a chassis of OA equipment in which sheet metal or aluminum die casting has been used so far, high rigidity and dimensional accuracy that cannot be achieved by conventional resin compositions are required.

As a technique for imparting rigidity and dimensional accuracy to resins, a technique of blending an inorganic filler such as glass fiber is well known. However, when an inorganic filler with a large aspect ratio such as inorganic fibers or whiskers is added, the increase in rigidity is large, but when resin is molded by injection molding, for example, the direction perpendicular to the resin flow direction in the molded product A difference occurs in the molding shrinkage rate and the linear expansion coefficient. This causes the molded product to warp or causes a dimensional deviation, which makes it difficult to obtain a molded product with good dimensional accuracy. When a flaky inorganic filler such as glass flakes or mica is added, dimensional accuracy is improved, but rigidity is less likely to increase and weld strength is greatly reduced. When a large amount of an inorganic filler is added to obtain the desired rigidity, the impact resistance is significantly reduced, and the weld strength is significantly reduced, resulting in loss of practicality.

As described above, the conventional techniques cannot provide a resin composition having a high degree of rigidity and good dimensional accuracy while maintaining the practicality of the resin.

[0005]

DISCLOSURE OF THE INVENTION The present invention provides a resin composition mainly composed of a polyphenylene ether-based resin and a polystyrene-based resin with a high degree of rigidity and dimensional accuracy while maintaining its original desirable characteristics. It was made for the purpose.

[0006]

The present inventors have developed a resin composition mainly composed of a polyphenylene ether resin and a polystyrene resin, which has good rigidity, impact resistance, dimensional accuracy and appearance characteristics. As a result of repeated intensive research for, when the inorganic filler is compounded in the resin composition composed of the polyphenylene ether-based resin and the polystyrene-based resin, when the fibrous and scale-like inorganic fillers are used in combination,
It has been found that when the fibrous or scale-like inorganic fillers are used alone, almost no defects appear, and the balance between rigidity and dimensional accuracy is dramatically improved. In addition, the inventors have found that the impact resistance and the weld strength are not significantly lowered and that the appearance is not deteriorated, and thus the present invention has been completed.

That is, the present invention comprises (A) 100 parts by weight of a resin composition comprising a polyphenylene ether resin and a polystyrene resin, (B) an inorganic filler 10-200.
The present invention provides an inorganic filler-reinforced resin composition, characterized in that the inorganic filler as the component (B) is in the form of fibers or scales. Hereinafter, the present invention will be described in detail.

The polyphenylene ether resin, which is one of the basic resin components of the composition of the present invention, has the general formula (1)-
[A], (1)-[b],

[0009]

[Chemical 1]

(Wherein R ₁ , R ₂ , R ₃ , R ₄ , R ₅ ,
R ₆ is a monovalent residue such as an alkyl group having 1 to 4 carbon atoms, an aryl group, halogen or hydrogen, and R ₅ and R ₆ are not hydrogen at the same time. ) Is a repeating unit, and a homopolymer or a copolymer whose structural unit is represented by the above formulas 1 [a] and [b] can be used.

A typical example of a homopolymer of a polyphenylene ether resin is 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 mentioned.

The polyphenylene ether copolymer is 2,
Copolymer of 6-dimethylphenol and 2,3,6-trimethylphenol or copolymer of o-cresol or 2,3,6-trimethylphenol and o-
It includes a polyphenylene ether copolymer mainly composed of a polyphenylene ether structure such as a copolymer with cresol.

The polystyrene resin used as another basic component of the composition of the present invention is a styrene compound or a compound copolymerizable with the styrene compound in the presence or absence of a rubbery polymer. It is a polymer obtained by. The styrene compound is represented by the general formula (2),

[0014]

[Chemical 2]

(Wherein R represents hydrogen, lower alkyl or halogen, Z is selected from the group consisting of vinyl, hydrogen, halogen and lower alkyl, and p is an integer of 0 to 5). Means a compound. Specific examples thereof include styrene, α-methylstyrene, 2,4-dimethylstyrene, monochlorostyrene, p-methylstyrene, p-tert-butylstyrene, ethylstyrene and the like. The compounds copolymerizable with styrene compounds include "methacrylic acid esters such as methyl methacrylate and ethyl methacrylate", "unsaturated nitrile compounds such as acrylonitrile and methacrylonitrile", and acid anhydrides such as maleic anhydride. And the like, which are used together with the styrene compound. Examples of the rubbery polymer include conjugated diene rubbers, copolymers of conjugated dienes and aromatic vinyl compounds, ethylene-propylene copolymer rubbers, and the like.

The method for producing the styrene resin of the present invention is not limited, and any of bulk polymerization, solution polymerization, emulsion polymerization and suspension polymerization well known to those skilled in the art may be used. If necessary, other rubbery polymer such as styrene-butadiene block copolymer or hydrogenated product thereof can be added.

The type of the inorganic filler used in the composition of the present invention is not particularly limited, and those conventionally used as a reinforcing agent for thermoplastic resins such as inorganic salts, glass, carbon, metals and ceramics can be used. Any one can be appropriately selected and used according to required characteristics. As the fibrous inorganic filler, glass fiber, metal fiber or whiskers are mainly used. As the scaly inorganic filler, glass flakes, metal flakes such as aluminum, and mica are mainly used. It is essential that the inorganic filler includes both fibrous and scale-like fillers, but powders, granules, balloons and the like may be used in combination as long as this requirement is satisfied. The inorganic fillers may be used in any combination as long as the shape requirements are satisfied. Further, as long as the object of the present invention is not impaired, it is possible to use those that have been subjected to a surface treatment with a silane coupling agent or a focusing treatment with a sizing agent as desired.

The proportion of the constituent components in the inorganic filler is not particularly limited, but the proportion of fibrous and flaky substances in the inorganic filler is preferably 60% by weight or more. The proportion of the fibrous or scale-like substances in the filler is preferably 10% by weight or more. Ratio of fibrous and scale-like substances 60
This is because the balance of rigidity, dimensional accuracy, and weld strength is lost when the content is less than 10% by weight or the ratio of fibrous or scaly ones is less than 10% by weight.

In the composition of the present invention, the proportion of the polyphenylene ether resin in the component (A) is 10-9.
It is desirable to be selected from the range of 0% by weight. When the proportion of the resin is less than 10% by weight, it is not preferable because preferable properties derived from the polyphenylene ether resin are not exhibited, and when it exceeds 90% by weight, an extremely high molding temperature is required, which is not preferable.

The addition amount of the inorganic filler as the component (B) should be selected within the range of 10 to 200 parts by weight with respect to 100 parts by weight of the component (A). The amount of inorganic filler is 10
If the amount is less than 200 parts by weight, the effect of improving rigidity and dimensional accuracy is not sufficient, which is not preferable, and if the amount exceeds 200 parts by weight, impact resistance and appearance are significantly deteriorated, which is not preferable.

In the composition of the present invention, a flame retardant may be added to impart flame retardancy, if desired. The flame retardant is not particularly limited, and any one can be selected from those conventionally used for flame retarding thermoplastic resins and thermosetting resins and used. Among them, aromatic phosphates are preferable. If desired, the composition of the present invention may further contain stabilizers such as antioxidants, ultraviolet absorbers and heat stabilizers and other known additives within a range that does not impair the object of the present invention. it can.

The method for preparing the composition of the present invention is not particularly limited, and it is a method conventionally used for thermoplastic resin compositions, that is, each component is mixed, and an extruder, a heating roll,
A method of melt-kneading using a kneader, Banbury mixer, or the like is used.

[0023]

EXAMPLES Next, the present invention will be described in more detail with reference to examples, but the present invention is not limited to these examples. Parts or% in the examples mean parts by weight or% by weight, respectively. The physical properties shown in Examples and Comparative Examples are measured by the following measuring methods for test pieces obtained by pelletizing the composition and injection molding.

(1) Izod impact strength (with notch) Determined in accordance with ASTM D256. (2) Flexural modulus It was determined according to ASTM D790. (3) Weld strength The tensile strength of a dumbbell test piece formed by a one-end gate and having no weld part and a dumbbell test piece formed by a double-end gate and having a weld part at the center are respectively A.
After being determined in accordance with STM D638, the weld strength, which was obtained by dividing the strength of the welded portion with the strength of the welded portion, was shown as the weld strength.

(4) Linear expansion coefficient Strain is removed by annealing, and ASTM D618 is used.
Using a test piece pretreated by the method of 1., the resistance line strain meter was used to measure the temperature in the range of -30 to 80 ° C according to the method of ASTM D696. The linear expansion coefficient was determined in the flow direction of the resin of the test piece and the direction perpendicular to the flow direction. The coefficient of linear expansion in the perpendicular direction divided by the coefficient of linear expansion in the flow direction was expressed as the anisotropy of the coefficient of linear expansion.

[0026]

Example 1 Poly (2,6-dimethyl-1,4-phenylene) ether 30 parts High-impact polystyrene 20 parts containing 10% polybutadiene component, polystyrene 20
Parts, 0.5 parts of 2,6-di-tert-butyl-4-methylphenol, 15 parts of aminosilane-treated glass fibers having a diameter of 13 μm and an average length of 3 mm, and 15 parts of aminosilane-treated mica having an average flake diameter of 90 μm. And were melt-kneaded at a temperature of 300 ° C. using an extruder to obtain a composition, and the physical properties were evaluated. The evaluation results are shown in Table 1.

[0027]

Comparative Example 1 A composition was obtained by repeating Example 1 except that the mica was changed to glass fiber, and the physical properties were evaluated. The evaluation results are shown in Table 1.

[0028]

Comparative Example 2 A composition was obtained by repeating Example 1 except that the glass fiber was changed to mica, and the physical properties were evaluated. The evaluation results are shown in Table 1.

[0029]

Example 2 40 parts of poly (2,6-dimethyl-1,4-phenylene) ether, 15 parts of polystyrene, 5 parts of triphenylene phosphate, 0.5 part of 2,6-di-tert-butyl-4-methylphenol. 300 parts of an aminosilane-treated cut glass fiber having a diameter of 13 μm and an average length of 70 μm and 20 parts of an aminosilane-treated mica having an average flake diameter of 90 μm were used for 300 times.
The composition was obtained by melt-kneading at a temperature of ° C and the physical properties were evaluated. The evaluation results are shown in Table 1.

[0030]

Comparative Example 3 A composition was obtained by repeating Example 2 except that mica was used as the cut glass fiber, and the physical properties were evaluated. The evaluation results are shown in Table 1.

[0031]

[Table 1]

[0032]

The composition of the present invention is a molding material having good rigidity, impact resistance, dimensional accuracy and appearance characteristics.
It is industrially useful, including fields such as chassis for equipment A.

Claims (1)

[Claims] 1. An inorganic filler which is a component (B), comprising 100 parts by weight of a resin composition comprising (A) a polyphenylene ether resin and a polystyrene resin and (B) an inorganic filler in an amount of 10 to 200 parts by weight. Is a fibrous or scaly material, and the inorganic filler-reinforced resin composition is characterized in that: