JPH07324164A - Polyarylene sulfide resin composition - Google Patents

Abstract

PURPOSE:To provide a polyarylene sulfide resin composition reduced in the formation of burrs, being excellent in flow and having practical excellent mechanical properties. CONSTITUTION:This composition comprises 100 pts.wt. polyarylene sulfide resin, 5-150 pts.wt. whiskery calcium carbonate and optionally 150 pts.wt. or below inorganic filler other than the whiskery calcium carbonate.

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 having little burr during molding, excellent fluidity, and practically excellent mechanical properties.

[0002]

2. Description of the Related Art In recent years,
High heat resistance, mechanical properties, chemical resistance, dimensional stability, and flame-retardant thermoplastic resin are required for electric / electronic equipment parts materials, automobile equipment parts materials, and chemical equipment parts materials. Is coming. Polyarylene sulfide (PAS) resin typified by polyphenylene sulfide (PPS) is also one of the resins meeting this demand,
In general, compounding fibrous reinforcing materials such as glass fibers and other inorganic fillers improves the physical properties and increases the demand.
In particular, calcium carbonate is inexpensive as a filler and is known as an example of a filler which is preferable in terms of physical properties. However, when the PAS-based resin or its composition is molded by injection molding or the like, the resin particularly flows into the joining surface of the mold,
There is a drawback that so-called burrs are easily formed, which has become a particular problem when performing precision molding. The burr of this molded product can be removed by a deburring finishing after molding, but this finishing requires a great deal of labor and cost depending on the shape of the product. Several proposals have been made to date for reducing the occurrence of burrs in a PAS resin. A method of adding a polycarbodiimide compound (Japanese Patent Laid-Open No. 61-14251) and a specific cross-linked PA
A method in which S is added and used in combination (JP-A 64-9266), and a method in which an alkali metal organophosphate compound is added (JP-A 1-
No. 54066), a method of adding an organic aluminum compound (Japanese Patent Application Laid-Open No. 2-191666), and the like.
However, in these conventional techniques, the effect of reducing burrs is insufficient, or other physical properties are hindered, and there is a problem that mechanical properties are deteriorated or fluidity is deteriorated. There is a strong demand for a PAS-based resin material that simultaneously satisfies the requirements of reduction of generation and molding processability and mechanical properties.
That is, generally, the occurrence of burrs tends to be reduced by increasing the viscosity of the resin material, but the increase in viscosity hinders the fluidity and deteriorates the moldability, prolongs the molding cycle, and increases the original cavity. If the resin pressure at the time of molding is increased in order to avoid insufficient filling of the tee, burrs are generated, which is also a problem.

[0003]

The inventors of the present invention have conducted research to solve the above-mentioned problems, and as a result, in a PAS resin composition containing calcium carbonate as one component of a filler, specific whisker-like particles were used as the calcium carbonate to be used. The present invention has been completed by finding that the above problems can be improved and the object thereof can be achieved by adding and blending (acicular) calcium carbonate. That is, the present invention comprises (A) 100 parts by weight of 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.

The structure of the present invention will be described in detail below. 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 '
-Diphenylene carbonyl group, naphthalene group and the like.
In this case, in the arylene sulfide group composed of the above-mentioned arylene group, a polymer using the same repeating unit, that is, a homopolymer can be used, and depending on the purpose, a copolymer containing different repeating units is preferable. In some cases. A typical example of the homopolymer is PPS having a p-phenylene sulfide group as a repeating unit, which uses a p-phenylene group as an arylene group, and among them, substantially linear PPS is particularly preferably used. Further, as the copolymer, mainly the arylene sulfide group consisting of the above arylene group,
Copolymers composed of two or more different types can be used, but among them, a combination mainly composed of p-phenylene sulfide group and another repeating unit is particularly preferably used. Among these, p-phenylene sulfide group
Substantially linear ones containing 60 mol% or more, more preferably 70 mol% or more are suitable from the viewpoint of physical properties such as heat resistance, moldability and mechanical properties. In this case, it is preferable that the repeating units of the component contained in the block form have better processability, heat resistance, and mechanical properties than those in the random form, and can be preferably used. Examples of preferable copolymerization component include, but are not limited to, m-phenylene group. 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 a relatively low molecular weight linear polymer is increased in melt viscosity by oxidative crosslinking or thermal crosslinking. Polymers having improved molding processability can also be used.
It is also possible to use a PAS resin having an arbitrary branched or crosslinked structure obtained by polymerizing a small amount of a monomer having three or more functional groups together as a part of the monomer. Particularly, a blended resin obtained by blending the above-mentioned linear polymer with PAS having an appropriately branched or crosslinked structure is particularly effective and suitable for preventing the occurrence of burrs which is the object of the present invention. Further, the PAS resin used in the present invention may be a modified PAS having various substituents introduced therein.

Next, 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, and the aragonite type is particularly preferable, and the average measured by the microscopic method. Fiber diameter (minor diameter) 0.05 to 4.0 μ
m, an average fiber length (major axis) of 0.5 to 80 μm, and an average aspect ratio of 5 or more, whisker-like (acicular) calcium carbonate is preferable. Among them, the average fiber diameter is 0.
1 to 2.0 μm, average fiber length of 1.0 to 50 μm, and average aspect ratio of 10 to 80 are preferable, further average fiber diameter is 0.2 to 2.0 μm, average fiber length is 10 to 40 μm, and average aspect ratio. The whisker-like calcium carbonate having a number of 10 to 80 is particularly effective in that it significantly reduces the occurrence of burrs during molding, exhibits excellent fluidity, and exhibits excellent mechanical strength and dimensional stability. Such whisker-like calcium carbonate is prepared, for example, by introducing carbon dioxide gas into an aqueous slurry of calcium hydroxide and appropriately controlling the reaction conditions at the time of reaction, and the presence of a suitable seed crystal (for example, aragonite-based crystal nucleus) The method is particularly effective for obtaining a preferable shape, but the preparation method is not particularly limited, and the point is that the shape and shape described above are essential. The 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 10 parts by weight, relative to 100 parts by weight of PAS.
0 parts by weight. If this amount is too small, the effect of reducing burrs cannot be obtained, and if it is too large, problems occur in extrudability and molding processability, and it is not preferable in terms of mechanical properties. The amount of whisker-like calcium carbonate compounded is also related to the amount of other filler (C) described later. In the present invention, whisker-like calcium carbonate is effective even if it is not particularly surface-treated, but whisker-like calcium carbonate treated with a surface-treating agent on the surface is used as a PAS resin. The affinity is improved, which is preferable. The surface treatment agent used is, for example, silane-based, titanate-based, aluminum-based,
Various coupling treatment agents such as epoxy type, zirconate type and urethane type are exemplified. Specific examples include γ-aminopropyltriethoxysilane, 3-glycidoxypropyltrimethoxysilane, isopropyltristearoyl titanate, diisopropoxyaluminum ethyl acetate, n-butylzirconate.

Next, in the composition of the present invention, a filler (C) other than the whisker-like calcium carbonate can be used in combination. The filler of the component (C) used in the present invention is not always an essential component, but it should be blended in order to obtain a molded product excellent in mechanical strength, rigidity, heat resistance, and dimensional stability. 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 substances such as metallic fibrous substances such as stainless steel, aluminum, titanium, copper and brass can be used. Further, a high melting point organic fibrous substance such as a fluororesin or an aramid resin may be used. A particularly representative fibrous filler is glass fiber or carbon fiber. On the other hand, as the granular filler, carbon black, silica, quartz powder, glass beads, glass powder, calcium silicate, aluminum silicate, kaolin, talc, clay, silicates such as diatomaceous earth, wollastonite, and oxidation. Iron, zinc oxide, titanium oxide, metal oxides such as alumina, barium sulfate, metal sulfates such as sodium sulfate, amorphous or granular calcium carbonate other than the component (B) used in the present invention, magnesium carbonate , Metal carbonates such as zinc carbonate, silicon carbide, silicon nitride and the like. Examples of the plate-like filler include mica and glass flakes. Since these fillers improve the mechanical strength of the composition, it is desirable to pretreat them with a sizing agent or a surface treatment agent. Examples of the treating agent include epoxy compounds, isocyanate compounds, silane compounds, titanate compounds and the like. Two or more kinds of the fillers as the component (C) may be used in combination. The amount of the fibrous filler (C), the granular filler, and the plate-like filler used is also related to the blending amount with the whisker-like calcium carbonate, and is 1 per 100 parts by weight of the PAS resin.
It is 50 parts by weight or less, preferably 5 to 100 parts by weight, and the total amount of the whisker-like calcium carbonate (B) is preferably 250 parts by weight or less based on 100 parts by weight of the PAS resin. If it is too large, the moldability is impaired and the mechanical properties are deteriorated, which is not preferable.

Next, the composition of the present invention is not necessarily essential, but it is preferable to add an alkoxysilane compound (D). The alkoxysilane (D) is at least one selected from the group consisting of aminoalkoxysilane, vinylalkoxysilane, epoxyalkoxysilane, mercaptoalkoxysilane and allylalkoxysilane. As aminoalkoxysilane,
Have one or more amino groups in one molecule and two alkoxy groups
Any silane compound having 3 or 3 silane compounds 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, and examples thereof include vinyltriethoxysilane and vinyltrimethoxysilane. , Vinyl tris (β-methoxyethoxy)
Examples include silane. As the epoxyalkoxysilane, any silane compound having one or more epoxy groups and two or three alkoxy groups in one molecule is effective, and for example, γ-glycidoxypropyltrimethoxysilane. , Β- (3,4-epoxycyclohexyl) ethyltrimethoxysilane, γ-glycidoxypropyltriethoxysilane and the like. As the 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. The allylalkoxysilane has one or more allyl groups in one molecule and two or three alkoxy groups.
Any silane compound is effective as long as it has silane compounds, for example, γ-diallylaminopropyltrimethoxysilane, γ-allylaminopropyltrimethoxysilane,
γ-allylthiopropyltrimethoxysilane and the like can be mentioned. Of the above silane compounds, aminoalkoxysilanes are most preferred for the purposes of the present invention.

The amount of the above-mentioned alkoxysilane (D) is PA
5 parts by weight or less, preferably 0.
It is 1 to 5 parts by weight, more preferably 0.1 to 2 parts by weight. When it is too large, the viscosity of the composition increases, which is not preferable.

The composition of the present invention further has a toning effect,
If necessary, pigments or dyes may be added to adjust the color tone. Known substances generally added to PAS resins according to purposes, that is, various stabilizers, antistatic agents,
A flame retardant, a lubricant, and a crystallization accelerator, a crystal nucleating agent, a releasing agent, a plasticizer and the like can be appropriately added as necessary.
In addition, a small amount of other thermoplastic resin, such as polyolefin resin, polyamide resin, styrene resin (A
S, ABS, etc.), polyester resin, polyether resin, etc. may be blended.

The resin composition of the present invention can be prepared by the equipment and method generally used for preparing a synthetic resin composition. Generally, necessary components can be mixed, melt-kneaded using a single-screw or twin-screw extruder, and extruded to obtain molding pellets. Alternatively, the resin component may be melt-extruded, and other components may be added and compounded during the process, or a master batch containing a part of the components may be prepared in advance and compounded and used for molding. The material pellets thus obtained may be used in any molding method, but most effective in injection molding and blow molding.

[0011]

The present invention will be described in more detail with reference to the following examples, but the present invention is not limited thereto. Examples 1 to 17 and Comparative Examples 1 to 7 For PPS resin (manufactured by Kureha Chemical Industry Co., Ltd.), various calcium carbonates (Table 1) as component (B), glass fiber as component (C), and (D). Alkoxysilane as a component
The amounts shown in Table 4 were added, mixed for 2 minutes with a blender and melt-kneaded with an extruder having a cylinder temperature of 310 ° C. to prepare pellets of PPS resin material. Then, as shown in FIG.
A burr measuring part with a mold gap of 20 μm in part is injection-molded using a mold with a disk-shaped cavity provided on the outer periphery, and the burr length generated in that part is projected with a map projector. It was enlarged and measured. The molding conditions are as follows: 5
Each shot is molded and the average value is shown (Tables 2 to 4). Mold temperature 150 ℃ Cylinder temperature 320 ℃ Injection pressure Minimum pressure required to completely fill the tab in Figure 1 (listed in Tables 2-4) Holding time 10 seconds Cooling time 10 seconds Using the same pellets, Toyo Seiki The melt viscosity was measured by a Capillograph 1B type device manufactured by Seisakusho (manufactured by). The capillary used was 1 mmφ × 10 mmL, and the value at a temperature of 310 ° C. and a shear rate of 1200 / sec was taken as the melt viscosity. Furthermore, using an injection molding machine, the cylinder temperature is 320 ° C and the mold temperature is 150 ° C.
Tensile test pieces according to 638 and bending test pieces according to ASTM D 790 were molded, and the strength and the like were measured. The results are also shown in Tables 2-4. Table 1 shows the types and shapes of the calcium carbonate and glass fiber used.

[0012]

[Table 1]

[0013]

[Table 2]

[0014]

[Table 3]

[0015]

[Table 4]

[0016]

EFFECTS OF THE INVENTION The polyarylene sulfide resin composition of the present invention has very few burrs on a molded product during molding, has good fluidity and excellent moldability, and has good mechanical properties. It has well-balanced characteristics and is extremely useful in practical use.

[Brief description of drawings]

FIG. 1 is a diagram 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 part 1'Burr length 2 Tab 3 Gate position 4 Mold dividing surface

Claims (6)

[Claims] 1. (A) Polyarylene sulfide resin 100
A molding polyarylene sulfide resin composition comprising (B) 5 to 150 parts by weight of whisker-like calcium carbonate and (C) 0 to 150 parts by weight of an inorganic filler other than (B). 2. The whisker-like calcium carbonate as the component (B) has an average fiber diameter (minor axis) of 0.05 to 4.0 μm, an average fiber length (major axis) 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 as the component (B) has an average fiber diameter (minor axis) of 0.1 to 2.0 μm, an average fiber length (major axis) 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. 4. The molding polyarylene sulfide resin composition according to claim 1, wherein the component (B) is whisker-like calcium carbonate surface-treated with a surface-treating agent. 5. The component (C) is glass fiber or carbon fiber 5
To 100 parts by weight, The polyarylene sulfide resin composition for molding according to any one of claims 1 to 4. 6. (A) Polyarylene sulfide resin 100
Further, (D) an alkoxysilane compound is added to the weight part.
The polyarylene sulfide resin composition for molding according to any one of claims 1 to 5, which is blended in an amount of 0.1 to 5 parts by weight.