JP3043570B2 - Polyarylene sulfide resin composition - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a polyarylene sulfide resin composition which is free from burrs during molding, has excellent fluidity, and has practically excellent mechanical properties.

[0002]

2. Description of the Related Art In recent years,
Electrical and electronic equipment parts materials, automotive equipment parts materials, and chemical equipment parts materials require thermoplastic resins that have high heat resistance, mechanical properties, chemical resistance, dimensional stability, and flame retardancy. Is coming. Polyarylene sulfide (PAS) resin typified by polyphenylene sulfide (PPS) is also one of the resins that meet this demand.
In general, the physical properties are improved by blending a fibrous reinforcing material such as glass fiber and other inorganic fillers, and the demand thereof is growing.
In particular, calcium carbonate is known as an example of a filler which is inexpensive as a filler and has favorable physical properties. However, when the PAS-based resin or its composition is molded by injection molding or the like, the resin flows particularly into the joining surface of the mold,
There is a drawback that so-called burrs are easily generated, which is a problem particularly when precision molding is performed. The burr of this molded product can be removed by deburring after molding, but depending on the product shape, this finishing requires a great deal of labor and cost. Several methods have been proposed so far to reduce the burr generation of the PAS resin, including a method of adding a polycarbodiimide compound (Japanese Patent Application Laid-Open No. 61-14251) and a method of forming a specific crosslinked PA.
A method in which S is added and used (JP-A-64-9266), and a method in which an alkali metal phosphate organic compound is added (Japanese Patent Laid-Open No.
No. 54066) and a method of adding an organoaluminum compound (JP-A-2-191666).
However, in these conventional techniques, there is a problem that the effect of reducing burrs is insufficient or other physical properties are hindered, for example, a decrease in mechanical properties and a deterioration in fluidity occur simultaneously. There is a strong demand for a PAS-based resin material that simultaneously satisfies the reduction of generation and the moldability and mechanical properties.
That is, in general, the occurrence of burrs tends to be reduced by increasing the viscosity of the resin material. However, the increase in the viscosity impairs the flowability and deteriorates the moldability, so that the molding cycle becomes longer, and the original mold is removed. Insufficient filling of the tee occurs, and if the resin pressure during molding is increased to avoid this, burrs are generated, which is also a problem.

[0003]

The inventors of the present invention have studied to solve the above-mentioned problems, and as a result, in a PAS resin composition containing calcium carbonate as a component of a filler, a specific whisker-like form was used as calcium carbonate to be used. It has been found that the above problems can be improved by adding and blending (needle-shaped) calcium carbonate, and the object can be achieved, and the present invention has been completed. That is, the present invention comprises (A) 100 parts by weight of a polyarylene sulfide resin, (B) 5 to 150 parts by weight of whisker-like calcium carbonate, (C) 0 to 150 parts by weight of an inorganic filler other than (B). It is a polyarylene sulfide resin composition for molding.

Hereinafter, the configuration of the present invention will be described in detail. The PAS resin as the component (A) in the composition of the present invention is mainly composed of a repeating unit (-Ar-S-) (where Ar is an arylene group). Arylene group (-Ar
-), for example p- phenylene, m- phenylene, o- phenylene group, substituted phenylene group (wherein the substituent is an alkyl group, preferably an alkyl group of C ₁ -C ₅ or a phenyl group,), p, p'-diphenylene sulfone group, p, p'-
Biphenylene group, p, p'-diphenylene ether group, p, p '
-Diphenylenecarbonyl group, naphthalene group and the like.
In this case, among the arylene sulfide groups composed of the above-mentioned arylene groups, a polymer using the same repeating unit, that is, a homopolymer can be used, and depending on the purpose, a copolymer containing a heterogeneous repeating unit is preferable. In some cases. As the homopolymer, a PPS using a p-phenylene group as an arylene group and having a p-phenylene sulfide group as a repeating unit is a typical one, and among them, a substantially linear PPS is particularly preferably used. Further, as the copolymer, mainly comprising an arylene sulfide group comprising the above-mentioned arylene group,
Copolymers consisting of two or more different combinations can be used. Among them, a combination mainly with a p-phenylene sulfide group and another repeating unit is particularly preferably used. In this, the p-phenylene sulfide group is
Substantially linear ones containing at least 60 mol%, more preferably at least 70 mol% are suitable from the viewpoint of physical properties such as heat resistance, moldability and mechanical properties. In this case, those in which the repeating units of the components are contained in a block form rather than in a random form have good workability, are excellent in heat resistance and mechanical properties, and can be preferably used. A preferable copolymerization component includes, for example, an m-phenylene group, but is not limited thereto. The PAS resin used in the present invention is preferably a high molecular weight polymer having a substantially linear structure obtained by polycondensation from a bifunctional monomer, but increases the melt viscosity of a relatively low molecular weight linear polymer by oxidative crosslinking or thermal crosslinking. Thus, a polymer having improved moldability can be used.
Further, a PAS resin having an arbitrary branched or cross-linked structure obtained by polymerizing a small amount of a monomer having three or more functional groups as a part of the monomer can also be used. In particular, a blended resin obtained by blending the above-mentioned linear polymer having a moderately branched or crosslinked PAS with the linear polymer is particularly effective and preferable in preventing the generation of burrs, which is the object of the present invention. Further, the PAS resin used in the present invention may be a modified PAS into which various substituents are introduced.

The whisker-like calcium carbonate used as the component (B) in the present invention is a synthetic calcium carbonate belonging to the aragonite type or the calcite type in terms of crystal classification. Fiber diameter (short diameter) 0.05-4.0 μ
m, average fiber length (major diameter) is 0.5 to 80 μm, and whisker-like (needle-like) calcium carbonate having an average aspect ratio of 5 or more is preferable. Among them, the average fiber diameter is 0.
It is preferable that the average fiber length is 1 to 2.0 μm, the average fiber length is 1.0 to 50 μm, and the average aspect ratio is 10 to 80, and the average fiber diameter is 0.2 to 2.0 μm, the average fiber length is 10 to 40 μm, and the average aspect ratio. The whisker-like calcium carbonate having a particle size of 10 to 80 is particularly effective in that it significantly reduces the generation of burrs at the time of molding, exhibits excellent fluidity, and exhibits excellent values of both mechanical strength and dimensional stability. Such whisker-like calcium carbonate is prepared, for example, by appropriately controlling the reaction conditions when introducing and reacting carbon dioxide gas into a water slurry of calcium hydroxide, and the presence of an appropriate seed crystal (eg, aragonite crystal nucleus) Although it is particularly effective for obtaining a preferable shape, its preparation method is not particularly limited, and it is essential that the material has the above-mentioned dimensions and shape. The blending amount of the (B) whisker-like calcium carbonate in the present invention is 5 to 150 parts by weight, preferably 10 to 100 parts by weight, particularly preferably 20 to 100 parts by weight based on 100 parts by weight of PAS.
0 parts by weight. If the amount is too small, the effect of reducing burrs cannot be obtained. If the amount is too large, problems arise in extrudability and moldability, and it is not preferable in terms of mechanical properties. The amount of the whisker-like calcium carbonate is related to the amount of the other filler (C) described later. In the present invention, the whisker-like calcium carbonate is effective without any particular surface treatment. However, it is effective to use a whisker-like calcium carbonate obtained by treating the surface of the whisker-like calcium carbonate with a surface treatment agent and attaching the same. Affinity is improved and preferred. The surface treatment agent used is, for example, silane-based, titanate-based, aluminum-based,
Various coupling agents such as epoxy-based, zirconate-based, and urethane-based are exemplified. Specifically, γ-aminopropyltriethoxysilane, 3-glycidoxypropyltrimethoxysilane, isopropyltristearoyl titanate, diisopropoxyaluminum ethyl acetate, n-butyl zirconate and the like can be mentioned.

Next, in the composition of the present invention, a filler (C) other than whisker-like calcium carbonate can be used in combination. The filler of the component (C) used in the present invention is not an essential component, but should be blended in order to obtain a molded article having excellent mechanical strength, rigidity, heat resistance, and dimensional stability performance. Is preferred. For this purpose, a fibrous, powdery or plate-like filler is used depending on the purpose. As the fibrous filler, glass fiber, carbon fiber, silica fiber, silica / alumina fiber, zirconia fiber, boron nitride fiber,
Silicon nitride fiber, boron fiber, potassium titanate fiber, calcium sulfate fiber, asbestos fiber, aluminum borate fiber,
In addition, inorganic fibrous materials such as fibrous materials of metals such as stainless steel, aluminum, titanium, copper, and brass can be used. Further, high melting point organic fibrous substances such as fluororesins and aramid resins can also be used. Particularly typical fibrous fillers are glass fibers or carbon fibers. On the other hand, as the particulate filler, carbon black, silica, quartz powder, glass beads, glass powder, calcium silicate, aluminum silicate, kaolin, talc, clay, diatomaceous earth, silicate such as wollastonite, oxide Metal oxides such as iron, zinc oxide, titanium oxide and alumina, metal sulfates such as barium sulfate and sodium sulfate, amorphous or granular calcium carbonate and magnesium carbonate other than the component (B) used in the present invention And metal carbonates such as zinc carbonate and the like, silicon carbide, silicon nitride and the like. Examples of the plate-like filler include mica and glass flake. These fillers are desirably treated in advance with a sizing agent or a surface treatment agent in order to improve the mechanical strength of the composition. Examples of the treating agent include an epoxy compound, an isocyanate compound, a silane compound, a titanate compound, and the like. The filler of the component (C) may be used in combination of two or more kinds. (C) The amount of the fibrous filler, the particulate filler, and the platy filler used as the component is also related to the amount of the whisker-like calcium carbonate to be added.
It is preferably 50 parts by weight or less, more preferably 5 to 100 parts by weight, and the total amount of the whisker-like calcium carbonate (B) is 250 parts by weight or less based on 100 parts by weight of the PAS resin. If it is excessively large, the molding processability is impaired and the mechanical properties are undesirably reduced.

Next, the composition of the present invention is preferably, but not necessarily, further added with an alkoxysilane compound (D). The alkoxysilane (D) is composed of at least one selected from the group consisting of aminoalkoxysilane, vinylalkoxysilane, epoxyalkoxysilane, mercaptoalkoxysilane and allylalkoxysilane. As aminoalkoxysilane,
One molecule has one or more amino groups and two alkoxy groups
Any of the silane compounds having three or three is effective, for example, γ-aminopropyltrimethoxysilane, γ-aminopropyltriethoxysilane, γ-aminopropylmethyldimethoxysilane, γ-aminopropylmethyldiethoxysilane , N- (β-aminoethyl) -γ-aminopropyltrimethoxysilane, N-phenyl-γ-aminopropyltrimethoxysilane and the like. As the vinylalkoxysilane, any silane compound having one or more vinyl groups in one molecule and having two or three alkoxy groups is effective. For example, vinyltriethoxysilane, vinyltrimethoxysilane , Vinyl tris (β-methoxyethoxy)
Silane and the like. As the epoxyalkoxysilane, any silane compound having one or more epoxy groups in one molecule and having two or three alkoxy groups is effective. For example, γ-glycidoxypropyltrimethoxysilane is effective. , Β- (3,4-epoxycyclohexyl) ethyltrimethoxysilane, γ-glycidoxypropyltriethoxysilane and the like. As a mercaptoalkoxysilane, any silane compound having one or more mercapto groups in one molecule and having two or three alkoxy groups is effective.
For example, γ-mercaptopropyltrimethoxysilane, γ
-Mercaptopropyltriethoxysilane and the like. As the allylalkoxysilane, one molecule has at least one allyl group and two or three alkoxy groups.
Any silane compound is effective as long as it has, for example, γ-diallylaminopropyltrimethoxysilane, γ-allylaminopropyltrimethoxysilane,
γ-allylthiopropyltrimethoxysilane and the like. For the purposes of the present invention, among the above silane compounds, aminoalkoxysilanes are most preferred.

The compounding amount of the above alkoxysilane (D) is PA
5 parts by weight or less, preferably 0.1 part by weight, based on 100 parts by weight of the S resin.
The amount is 1 to 5 parts by weight, more preferably 0.1 to 2 parts by weight. If it is too large, the viscosity of the composition increases, which is not preferable.

The composition of the present invention further comprises, for toning,
If necessary, a desired color tone can be adjusted by blending a pigment or a dye. In addition, known substances generally added to the PAS resin depending on the purpose, that is, various stabilizers, antistatic agents,
A flame retardant, a lubricant, a crystallization accelerator, a crystal nucleating agent, a release agent, a plasticizer, and the like can be appropriately added as necessary.
Also, a small amount of other thermoplastic resin such as polyolefin resin, polyamide resin, styrene resin (A
S, ABS, etc.), polyester resins, polyether resins and the like.

[0010] The resin composition of the present invention can be prepared by equipment and a method generally used for preparing a synthetic resin composition. Generally, necessary components are mixed, melt-kneaded using a single-screw or twin-screw extruder, and extruded to form molding pellets. Alternatively, the resin component may be melt-extruded, and other components may be added and compounded in the middle thereof, or a masterbatch containing some components may be prepared in advance, blended, and provided for molding. The material pellets thus obtained may be used for any molding method, but the effect is most exhibited in injection molding and blow molding.

[0011]

EXAMPLES The present invention will be described in more detail with reference to the following Examples, but it should not be construed that the invention is limited thereto. Examples 1 to 17, Comparative Examples 1 to 7 PPS resin (manufactured by Kureha Chemical Industry Co., Ltd.), various calcium carbonates (Table 1) as component (B), glass fibers as component (C), and (D) Table 2 shows alkoxysilane as a component.
The mixture was added in the amount shown in Table 4, mixed for 2 minutes by a blender, and melted and kneaded with an extruder having a cylinder temperature of 310 ° C. to produce pellets of a PPS resin material. Then, as shown in FIG.
A burr measuring part having a 20 μm mold gap is injection molded using a disk-shaped cavity mold provided on the outer periphery, and the burr length generated in that part is mapped by a projection projector. It was measured with magnification. The molding conditions are as follows, each of which is 5
The average value is shown for each shot (Tables 2 to 4). Mold temperature 150 ° C Cylinder temperature 320 ° C Injection pressure Minimum pressure required to completely fill the tub in Fig. 1 (described in Tables 2 to 4) Holding time 10 seconds Cooling time 10 seconds The melt viscosity was measured with a Capillograph 1B type machine (manufactured by Seisakusho). The capillary was 1 mmφ × 10 mmL, and the value at a temperature of 310 ° C. and a shear rate of 1200 / sec was defined as the melt viscosity. ASTM D at a cylinder temperature of 320 ° C and a mold temperature of 150 ° C using an injection molding machine.
A tensile test piece was formed according to 638, and a bending test piece was formed according to ASTM D790, and the strength and the like were measured. The results are shown in Tables 2 to 4. Table 1 shows the types and shapes of the used calcium carbonate and glass fiber.

[0012]

[Table 1]

[0013]

[Table 2]

[0014]

[Table 3]

[0015]

[Table 4]

[0016]

According to the polyarylene sulfide resin composition of the present invention, burrs of a molded article during molding are extremely low, the fluidity is good, the moldability is excellent, and the mechanical properties are good. The properties are satisfied in a well-balanced manner, and are extremely useful in practical use.

[Brief description of the drawings]

FIG. 1 is a view showing a mold of a disk-shaped cavity used for measuring a burr length in Examples, (a) is a plan view, and (b) is a schematic sectional view.

[Explanation of symbols]

 1 Burr measuring section 1 'Burr length 2 Tab 3 Gate position 4 Mold dividing surface

──────────────────────────────────────────────────続 き Continued on the front page (58) Field surveyed (Int. Cl. ⁷ , DB name) C08L 81/00-81/02 C08K 7/00-7/08 C08K 5/541-5/5419 C08K 9 / 04

Claims (6)

(57) [Claims] (A) Polyarylene sulfide resin 100
A polyarylene sulfide resin composition for molding comprising (B) 5 to 150 parts by weight of whisker-like calcium carbonate and 0 to 150 parts by weight of an inorganic filler other than (B) based on parts by weight. 2. The whisker-like calcium carbonate component (B) has an average fiber diameter (minor diameter) of 0.05 to 4.0 μm, an average fiber length (major diameter) of 0.5 to 80 μm, and an average aspect ratio of 5 or more. The polyarylene sulfide resin composition for molding according to claim 1. 3. The whisker-like calcium carbonate component (B) has an average fiber diameter (minor diameter) of 0.1 to 2.0 μm, an average fiber length (major diameter) of 1.0 to 50 μm, and an average aspect ratio of 10 to 80. The polyarylene sulfide resin composition for molding according to claim 1, which is: 4. The molding polyarylene sulfide resin composition according to claim 1, wherein the component (B) is a whisker-like calcium carbonate surface-treated with a surface treatment agent. 5. The composition according to claim 1, wherein the component (C) is glass fiber or carbon fiber 5.
The polyarylene sulfide resin composition for molding according to any one of claims 1 to 4, wherein the amount is from 100 to 100 parts by weight. 6. A polyarylene sulfide resin (A)
Further, (D) an alkoxysilane compound is added to parts by weight.
The polyarylene sulfide resin composition for molding according to any one of claims 1 to 5, which is contained in an amount of 0.1 to 5 parts by weight.