JPH11100505A - Polyarylene sulfide resin composition - Google Patents

Abstract

PROBLEM TO BE SOLVED: To improve corrosion and staining to molds for molding and metals used and to obtain a composition which has no adverse effect on mechanical properties such as tensile strength and elongation, impact strength and toughness by a corrosion inhibitor and has excellent metal corrosion resistance and mechanical properties by blending a specific amount of a zinc oxide whisker with a polyarylene sulfide resin(PAS resin). SOLUTION: 0.05-3 pts.wt. of a zinc oxide whisker is blended with 100 pts.wt. of a PAS resin. The PAS resin preferably has a p-phenylene sulfide group as an arylene group as a repeating unit in case of a homopolymer and preferably has a combination containing p-phenylene sulfide groups and m-phenylene sulfide groups in case of a copolymer. The zinc oxide whisker preferably has an average fiber diameter of 0.1 to 5 μm, an average fiber length of 2 to 100 μm and an average aspect ratio of 5 or more. The zinc oxide whisker is preferably surface-treated with an epoxy alkoxysilane or an amino alkoxysilane.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

The present invention relates to an improved polyarylene sulfide resin composition. More specifically, the present invention relates to a polyarylene sulfide resin composition which is excellent in molding processability, in particular, does not corrode or contaminate a metal part such as a mold during molding, and has excellent mechanical properties of a molded product.

[0002]

2. Description of the Related Art Polyarylene sulfide (hereinafter abbreviated as PAS) resin represented by polyphenylene sulfide (hereinafter abbreviated as PPS) resin has high heat resistance, mechanical properties, and chemical resistance. ,
Because of its dimensional stability and flame retardancy, it is widely used in electrical and electronic equipment parts materials, automotive equipment parts materials, chemical equipment parts materials, and the like. However, this resin has a sulfur atom in the molecular structure, and the production raw material has an alkali metal such as sulfur, chlorine and sodium,
It has the disadvantage that by-products containing large amounts of sulfur, chlorine, alkali metals, etc. are produced during resin synthesis,
It has the disadvantage of corroding and contaminating metal materials such as molds during molding,
In addition, when used as a molded part material, the metal inserted into the part, or the plated or evaporated metal corrodes,
There are problems such as contamination and trouble. As a means to solve this problem, it is proposed that the polymerized PAS resin be deionized with an acid, hot water, an organic solvent, etc., washed and reduced to 500 ppm or less, and even 200 ppm or less. Although very effective, the PAS resin and its composition have a very high molding processing temperature of at least 280 ° C.
Corrosive gas is generated during molding, and the corrosion resistance to metals is not sufficient. As a technique for solving this problem, there has been conventionally proposed a method of adding a harmful substance supplement to a resin to suppress corrosiveness and generation of impurities. For example, lithium carbonate (JP-A-54-162752), hydrotalcite (JP-A-61-275353), zinc carbonate,
Zinc hydroxide (JP-A-2-105857) and zinc borate (JP-A-6-306288) are exemplified. However, in the additional tests of the present inventors, although certain types of additives have been found to be effective to some extent in preventing corrosion of metals, they are still not sufficient, and there is a problem that a small amount of the additives causes a decrease in mechanical properties. Admitted. Japanese Patent Application Laid-Open No. 4-149691 discloses an example in which a specific zinc oxide is added. However, the mechanical properties are still not sufficient, and further improvement is desired.

[0003]

SUMMARY OF THE INVENTION In view of the foregoing, the present invention has been made to improve the corrosion and contamination of a metal mold during the molding of a PAS resin composition and the metal during its use, and to use a relatively large amount of a corrosion inhibitor. It is an object of the present invention to provide a PAS resin composition having excellent metal corrosion resistance and mechanical properties, without adverse effects on mechanical properties such as tensile strength and elongation, impact strength, and toughness even when used.

[0004]

Means for Solving the Problems The present inventors have conducted intensive studies to achieve the above object, and as a result,
By adding specific zinc oxide, corrosion and contamination of metals can be significantly improved, and adverse effects on mechanical properties by such a corrosion inhibitor can be eliminated, excellent mechanical properties can be maintained, and both properties can be maintained. As a result, the present invention has been completed. That is, the present invention relates to a polyarylene sulfide resin composition obtained by blending (B) 0.05 to 3 parts by weight of zinc oxide whiskers as a basic component and melt-kneading (A) 100 parts by weight of a polyarylene sulfide resin. It is.

[0005]

BEST MODE FOR CARRYING OUT THE INVENTION The constituents of the present invention will be described in detail below. The PAS resin as the component (A) in the composition of the present invention has a repeating unit of-(Ar-S)-(where Ar
Is an arylene group). Examples of the arylene group include a p-phenylene group and m-
Phenylene group, o-phenylene group, substituted phenylene group,
A p, p'-diphenylene sulfone group, a p, p'-biphenylene group, a p'p'-diphenylene ether group, a p, p'-diphenylenecarbonyl group, a naphthalene group and the like can be used. In this case, among the arylene sulfide groups composed of the above-mentioned arylene groups, in addition to a polymer using the same repeating unit, i.e., a homopolymer, a copolymer containing a heterogeneous repeating unit from the viewpoint of processability of the composition. Is sometimes preferred. As the homopolymer, one having a p-phenylene sulfide group as a repeating unit using a p-phenylene group as an arylene group is particularly preferably used. Further, as the copolymer, among the arylene sulfide groups comprising the above-mentioned arylene groups, two or more different combinations can be used. Among them, a combination containing a p-phenylene sulfide group and an m-phenylene sulfide group is particularly preferably used. Can be In this, p
Those containing 70% by mole or more, preferably 80% by mole or more of a phenylene sulfide group are suitable from the viewpoint of physical properties such as heat resistance, moldability, and mechanical properties. Also, these PAS
Among the resins, a high molecular weight polymer having a substantially linear structure obtained by condensation polymerization from a monomer mainly containing a bifunctional halogen aromatic compound can be particularly preferably used, but other than a PAS resin having a linear structure. In addition, when polycondensation is performed, a polymer having a partially branched or cross-linked structure formed by using a small amount of a monomer such as a polyhalo aromatic compound having three or more halogen substituents can be used,
It is also possible to use a polymer in which a low molecular weight linear polymer is heated at a high temperature in the presence of oxygen or an oxidizing agent to increase the melt viscosity by oxidative crosslinking or thermal crosslinking and improve moldability. In addition, the PAS resin of the component (A) is
AS (Viscosity at 310 ° C, shear rate 1200sec ^-1 is 10 ~ 30
0 Pa · s), and a part (1 to 30% by weight, preferably 2 to 25% by weight) of which has a relatively high viscosity (300 to 3000 Pa · s).
, Preferably 500 to 2000 Pa · s) branched or crosslinked PAS
A mixed system with a resin is also suitable. Also, the PA used in the present invention
After polymerization, the S resin is subjected to deionization treatment such as acid washing, hot water washing, and organic solvent washing (or a combination thereof) to remove and purify by-product impurities, thereby reducing the chlorine content and alkali metal content. 500 ppm or less, preferably 300 ppm each
The following are preferred.

Next, the zinc oxide whisker used as the component (B) in the present invention has an average fiber diameter (short diameter) of 0.1 to 5 μm and an average fiber length (long diameter) of 2 to 2 at the needle-like portion measured by a microscope. Those having a thickness of 100 μm and an average aspect ratio of 5 or more are preferred. Among commercially available products, zinc oxide having a three-dimensional tetrapot shape is one of compounds suitable as whiskers having the above-mentioned shape, but is not limited thereto. The amount of the component (B) is 0.05 to 3 parts by weight, preferably 0.1 to 1 part by weight, based on 100 parts by weight of the polyarylene sulfide resin. At 0.05 parts by weight, the effect of preventing corrosion of metals and the effect of suppressing contamination are not sufficient. If the amount exceeds 3 parts by weight, the same mechanical properties as in the case where the component (B) is not blended cannot be maintained. Further, the surface of the zinc oxide whisker of the component (B) is previously treated with epoxyalkoxysilane and / or aminoalkoxysilane,
It is preferable from the viewpoint of maintaining dispersibility and mechanical properties. 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. , Γ-glycidoxypropyltriethoxysilane and the like. As the aminoalkoxysilane, any silane compound having one or more amino groups in one molecule and having two or three alkoxy groups is effective.
For example, γ-aminopropyltrimethoxysilane, γ-aminopropyltriethoxysilane, N- (β-aminoethyl) -γ-aminopropyltrimethoxysilane and the like can be mentioned. The compounding amount of these alkoxysilanes is
Component (B) is preferably 0.05 to 5% by weight based on the zinc oxide whisker.

In the present invention, it is preferable to add phosphoric acid or hypophosphorous acid or a salt thereof as the component (C) because long-term wet heat resistance can be improved. Used here
(C) Phosphoric acid or hypophosphorous acid or a salt thereof includes, for example, primary phosphoric acid, hypophosphorous acid, calcium phosphate monobasic, sodium phosphate monobasic, calcium hypophosphite, zinc hypophosphite, magnesium hypophosphite, At least one kind or two or more kinds selected from salts of zinc such as sodium phosphite, and alkali metals or alkaline earth metals are mentioned, and calcium hypophosphite, magnesium hypophosphite and zinc hypophosphite are preferable. The amount of the component (C) is 0.05 to 2 parts by weight, preferably 0.1 to 1 part by weight, per 100 parts by weight of the polyarylene sulfide resin (A). If the amount is too small, the intended effect of improving the long-term wet heat resistance cannot be obtained,
On the other hand, if it is too large, there is a problem such as gas generation during molding, which is not preferable. By allowing the component (C) to coexist with the component (B), the interaction between the two components can be surprisingly prevented without impairing the effect of preventing corrosion and suppressing contamination of the metal possessed by the component (B). It was confirmed that the long-term wet heat resistance was improved. In particular, although it is effective to mix the component (C) as it is, a method in which part or all of the component (D) described below is preliminarily adhered to an inorganic or organic filler and then mixed with other components. Is also effective. There is no particular limitation on the method for attaching the component (C) .For example, a solution containing the above compound may be applied by spraying the filler onto the filler, and in the case of glass fiber or the like, the solution may be applied to the fiber using a roll coater. May be applied. It is also possible to treat with an epoxy resin, a urethane resin-based sizing agent or a coupling agent such as aminosilane or epoxysilane, which is generally used as a surface treatment agent for glass fiber or the like.

The inorganic or organic filler of component (D) used in the present invention is not an essential component, but includes mechanical strength, heat resistance, dimensional stability (warpage, deformation), electrical properties and the like. In order to obtain a molded article excellent in the performance of the, it is preferable to mix, fibrous, powdery or granular, depending on the purpose.
Alternatively, a plate-like filler or a mixture thereof is used.

Examples of the fibrous filler include glass fiber, asbestos fiber, carbon fiber, silica fiber, silica / alumina fiber, zirconia fiber, boron nitride fiber, silicon nitride fiber, boron fiber, potassium titanate fiber and the like. ,
Further, inorganic fibrous substances such as fibrous materials of metals such as stainless steel, aluminum, titanium, copper, and brass can be used.
Particularly typical fibrous fillers are glass fibers, carbon fibers, or potassium titanate fibers. In addition, a high-melting-point organic fibrous substance such as aromatic polyamide, acrylic resin, or fluororesin can also be used. On the other hand, as the granular filler, carbon black, graphite, silica, quartz powder, glass beads, glass powder, calcium silicate, aluminum silicate aluminum, kaolin, talc, clay, diatomaceous earth, silicates such as wollastonite, iron oxide, Examples thereof include oxides of metals such as titanium oxide and alumina, carbonates of metals such as calcium carbonate and magnesium carbonate, sulfates of metals such as calcium sulfate and barium sulfate, silicon carbide, silicon nitride, and various metal powders. Particularly typical ones are
Carbon black, silica, glass beads or glass powder, calcium carbonate, talc and the like. Examples of the plate-like filler include mica, glass flake, and various metal foils. These fillers can be used alone or in combination of two or more. The combined use of a fibrous filler, particularly a glass fiber or a carbon fiber, and a powdery or plate-like filler is a preferable combination, particularly in terms of having both mechanical strength, dimensional accuracy, electrical properties and the like. When using these fillers, if necessary, it is desirable to use a surface treatment with a sizing agent or a surface treatment agent or to use the filler after convergence. Examples of this treating agent include an epoxy compound, an isocyanate compound,
Functional compounds such as silane compounds and titanate compounds. The amount of the component (D) is from 1 to 75% by weight, preferably from 3 to 70% by weight, based on the total amount of the composition.
If it is excessively large, the molding operation becomes difficult, and there is a problem in the mechanical strength of the molded product.

Further, as the molded article composition used in the present invention, known substances generally added to a thermoplastic resin, that is, stabilizers such as antioxidants and ultraviolet absorbers, flame retardants, coloring such as dyes and pigments, etc. An agent, a lubricant, a crystallization accelerator, a crystal nucleating agent, and the like can be appropriately added according to required performance.

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 are mixed, melt-kneaded using a single-screw or twin-screw extruder, and extruded to form molding pellets. It is also a preferable method to melt-extrude a resin component and add and mix an inorganic component such as glass fiber during the extrusion. The material pellets obtained in this manner can be molded using a generally known thermoplastic resin molding method such as injection molding, extrusion molding, vacuum molding, compression molding, etc., but the most preferred is injection molding. .

[0012]

Next, the present invention will be described in detail with reference to examples and comparative examples, but the present invention is not limited to these examples. Examples 1 to 14 and Comparative Examples 1 to 10 As the component (A), substantially linear polyphenylene sulfide resin (manufactured by Kureha Chemical Industry Co., Ltd., “Fortron K”)
To 100 parts by weight of "PS", viscosity of 50 Pa · s (310 ° C., 1200 sec ⁻¹ ), the component (B) was added as shown in Tables 1 and 2, and mixed with a Henschel mixer for 2 minutes. Further, the components (C) and (D) were added in the amounts shown in Tables 1 and 2 and mixed with a blender for 30 seconds.
This was kneaded with an extruder having a cylinder temperature of 310 ° C. to produce pellets of the polyphenylene sulfide resin composition. The pellets were measured for metal corrosion, mechanical properties, and long-term wet heat resistance. The results are shown in Tables 1 and 2. Example 15 A solution of (C) calcium hypophosphite dissolved in a solvent was applied to glass fiber of the component (D) so as to have a ratio shown in Table 2, dried sufficiently, and dried in advance. A composition was prepared and evaluated under the same conditions as in the above example except that it was used. Table 2 shows the results.

The evaluation method is as follows. [Corrosion resistance] 4 g of the above pellets were placed in the bottom of a test tube having an inner diameter of 18 mm and a height of 160 mm, and a test piece (15 × 160 ×) of a mold material (SKD-11) mainly composed of iron, chromium and carbon was used.
2mm) was hung in place. Plug the top of the test tube,
After heating at 320 ° C. for 3 hours, the test piece was taken out and observed visually and microscopically to examine the corrosion state, and the relative grading was performed as follows according to the degree of the corrosion state. A B C D E ← ─────────────── → Corrosive small Corrosive large [Tensile elongation] Tensile with an injection molding machine at a cylinder temperature of 320 ° C and a mold temperature of 150 ° C. A test specimen is formed and the test specimen is AS
Tensile strength and tensile elongation were measured according to TM D-638. [Long-term wet heat resistance] Cylinder temperature 320 ° C with injection molding machine
A tensile test specimen was formed at a mold temperature of 150 ° C, and
ASTM D-638 after treatment in hot water at 500 ° C for 500 hours.
And the tensile strength was measured.

[0014]

[Table 1]

[0015]

[Table 2]

Note: (A) PPS (A-1); use deionized PPS (B) Corrosion inhibitor (B-1) Zinc oxide whisker (Epoxysilane treatment), manufactured by Matsushita Amtech, average fiber diameter (Minor axis) = 0.3 μm, average fiber length (major axis) = 4 μm (B-2) Matsushita Amtech Co., Ltd., zinc oxide whisker (aminosilane treatment), average fiber diameter (minor axis) = 0.3 μm, average fiber length (major axis) ) = 4 μm (B-3) manufactured by Matsushita Amtech Co., Ltd., zinc oxide whisker (untreated), average fiber diameter (minor diameter) = 0.3 μm, average fiber length (major diameter) = 4 μm (B-4) manufactured by Mitsui Mining & Smelting Co., Ltd. , Zinc oxide (dry method), average particle size = 0.7 μm (B-5) Sakai Chemical Co., zinc oxide (dry method), average particle size = 0.
04μm (B-6) Sakai Chemical Co., zinc oxide (wet method), average particle size = 0.
02μm (C) component (C-1) calcium hypophosphite

Claims (7)

[Claims] (A) Polyarylene sulfide resin 100
A polyarylene sulfide resin composition comprising (B) 0.05 to 3 parts by weight of zinc oxide whisker with respect to parts by weight. 2. The polyarylene according to claim 1, further comprising (C) 0.05 to 2 parts by weight of (C) phosphoric acid or hypophosphorous acid or a salt thereof with respect to 100 parts by weight of the polyarylene sulfide resin. A sulfide resin composition. 3. The polyarylene sulfide resin composition according to claim 2, wherein the component (C) is hypophosphite. 4. An inorganic or organic filler selected from fibrous fillers other than the component (B), powdery or granular fillers, and mixtures thereof as the component (D) in an amount of 1 to 75% by weight. The polyarylene sulfide resin composition according to any one of claims 1 to 3, which is blended with respect to the total amount of the composition. 5. The polyarylene sulfide resin composition according to claim 1, wherein the surface of the zinc oxide whisker (B) is previously treated with epoxyalkoxysilane and / or aminoalkoxysilane. 6. The polyarylene sulfide resin (A),
The polyarylene sulfide resin composition according to any one of claims 1 to 5, which is a polyarylene sulfide resin having a chlorine content and an alkali metal content of 500 ppm or less, respectively, which are deionized after polymerization. 7. The glass fiber or carbon fiber of component (D) is 3 to 70.
The polyarylene sulfide resin composition according to any one of claims 4 to 6, which is in terms of% by weight.