JP2608329B2 - Polyarylene sulfide resin composition - Google Patents

Description

The present invention relates to a polyarylene sulfide resin composition. More specifically, the present invention relates to a polyarylene sulfide resin composition in which the discoloration of a molded article is significantly improved.

[Conventional technology and its problems]

In recent years, electrical and electronic equipment parts materials, automobile equipment parts materials, and chemical parts materials have required thermoplastic resin compositions that have excellent mechanical properties, high heat resistance, chemical resistance, and flame retardancy. Have been.

A polyarylene sulfide resin typified by a polyphenylene sulfide resin is also one of the resins that meets this requirement, and the demand for the resin is increasing due to its good physical properties against cost.

However, when this resin is processed by injection molding or the like, the hue of the obtained molded product is discolored as a whole as compared with the hue of the pellet before molding, or black streaks and mottled discoloration occur on the surface of the molded product. There are many unfavorable phenomena in appearance such as problems, and problems such as discoloration when used at high temperature after molding (hereinafter abbreviated as "discoloration"). In order to solve this problem, as a technology to prevent discoloration,
Method of adding organic monophosphite (JP-A-47-17)
No. 35) has been proposed.

However, as a result of additional tests by the inventors,
It turns out that there are various problems. That is, the heat resistance of the additive is poor, and evaporative gas or decomposed gas tends to be generated during the molding process, and it cannot be said that the workability, physical properties, and appearance are sufficiently satisfactory.

[Means for Solving the Problems]

The present inventors have intensively studied to obtain a composition which suppresses discoloration and the like of a molded product during molding of a polyarylene sulfide resin composition, particularly a polyphenylene sulfide resin composition, and which does not generate decomposition gas. As a result, a composition containing an organic bisphosphite compound having two phosphorus atoms in a molecule represented by the following formula (1) has good thermal stability, extrudes a polyarylene sulfide resin, and decomposes gas at a molding temperature. Or, almost no evaporative gas is generated, there is no danger of ignition, and it does not impair the workability such as physical properties and moldability, and has a remarkable effect of reducing discoloration and the like as compared with the conventional art. It was The present inventors have further found that the addition of a specific silane-based compound to this compound has the effect of further improving the above-mentioned properties, and completed the present invention.

That is, the present invention relates to (A) 100 parts by weight of a polyarylene sulfide resin, and (B) 0.01 to 10 parts by weight of an organic bisphosphite compound represented by the following formula (1). (However, in the formula, R ₁ and R ₂ are an alkyl group, a substituted alkyl group,
A group selected from an aryl group, a substituted aryl group and an alkoxy group, which may be the same or different. (C) Inorganic filler: 0 to 400 parts by weight, and (D) 0.01 to 5 parts by weight of one or more silane compounds selected from aminoalkoxysilane, epoxyalkoxysilane, mercaptoalkoxysilane, vinylalkoxysilane And a polyarylene sulfide resin composition.

The base resin as the component (A) in the composition of the present invention is a polyarylene sulfide resin (PAS), which is composed of a main repeating unit Ar-S (where Ar is an arylene group).

Examples of the arylene group include (Where X is an alkyl group, preferably a C _{1 to} C ₆ alkyl group or a phenyl group, and n is an integer of 1 to 4.) Etc. can be used.

In this case, in the arylene sulfide group composed of the above-mentioned arylene group, it is preferable to use a polymer using the same repeating unit, that is, a homopolymer, but from the viewpoint of processability of the composition, a different repeating unit is used. Included copolymers may be preferred.

As the homopolymer, a substantially linear polymer 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 composed of the above-mentioned arylene groups, two or more different combinations can be used, but among them, a combination containing a p-phenylene sulfide group and an m-phenylene sulfide group is particularly preferably used. To be Among them, those containing 50 mol% or more, preferably 70 mol% or more of p-phenylene sulfide group are suitable from the viewpoint of physical properties such as heat resistance, moldability and mechanical properties.

In this case, the repeating unit of the component is contained in a block form rather than a random form (for example, JP-A-61-1
No. 14228), which have almost the same workability, but are excellent in heat resistance and mechanical properties and can be preferably used.

The polyarylene sulfide resin as the component (A) used in the present invention is a polymer having a substantially linear molecular structure obtained by condensation polymerization of a bifunctional monomer.

Among them, the melt viscosity measured at a temperature of 310 ° C. and a shear rate of 5 / sec is 1 × 10 to 5 × 10 ⁴ poise, preferably 50 to 5 poise.
× 10 ⁴ poises, particularly preferably substantially linear polymer in the range of 100 to 5 × 10 ⁴ poises is appropriate. If less than 10 poise, the fluidity is too good to be melt processed,
Even if a molded product is obtained, the mechanical strength is low, which is not preferable. On the other hand, if the porosity exceeds 5 × 10 ⁴ poise, the fluidity is poor and the melt processing is difficult.

In the present invention, any organic bisphosphite compound added as the component (B) is effective as long as it has a structure represented by the above formula (1).

(1) In the formula, R ₁ and R ₂ are an alkyl group, a substituted alkyl group,
It is selected from an aryl group, a substituted aryl group, and an alkoxy group, and may be the same or different.

Among them, R ₁ and R ₂ are preferably an alkyl group having 5 or more carbon atoms, a substituted alkyl group, an alkoxy group, or an aryl group or a substituted aryl group from the viewpoint of stability during processing.

Particularly preferred is a case where R ₁ and R ₂ are an alkyl group or an alkoxy group having 10 or more carbon atoms, or at least one of them is an aryl group or a substituted aryl group. In particular,
Structures A, B, C, D shown in Tables 1 to 3 (Note 1) of Examples described later
The following substances are mentioned as particularly preferred examples.

(B) represented by the above formula (1) used in the present invention
The amount of ingredients used is 100% polyarylene sulfide resin
It is 0.01-10 parts by weight per part by weight, preferably 0.1-
5 parts by weight. If it is too small, the intended effect cannot be obtained, and if it is too large, problems such as deterioration of physical properties and gas generation occur, which is not preferable.

Next, the inorganic filler of the component (C) used in the present invention includes:
Although it is not an essential component, it is preferable to mix it in order to obtain a molded article with excellent performance such as mechanical strength, heat resistance, dimensional stability (deformation resistance, warpage), and electrical properties. Are fibrous, non-fibrous (powder and granular,
A plate-like filler is used.

Examples of the fibrous filler include glass fiber, asbestos fiber, carbon fiber, silica fiber, silica / alumina fiber, zirconia fiber, nitrogen boron fiber, nitrogen silicon fiber, boron fiber, potassium titanate fiber, stainless steel, aluminum, titanium, Inorganic fibrous substances such as metallic fibrous substances such as copper and brass can be used. Particularly typical fibrous fillers are glass fibers or carbon fibers. In addition, high-melting point organic fibrous substances such as polyamide, fluororesin and acrylic resin can also be used.

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 Oxides of metals such as iron, titanium oxide, zinc oxide and alumina; carbonates of metals such as calcium carbonate and magnesium carbonate; sulfates of metals such as calcium sulfate and barium sulfate; other silicon carbide, silicon nitride, boron nitride; Various metal powders and the like can be mentioned.

Examples of the plate-like filler include mica, glass flakes, various metal foils and the like.

These inorganic fillers can be used alone or in combination of two or more. The combined use of a fibrous filler, particularly glass fiber or carbon fiber, with a granular and / or plate-like filler is a preferable combination particularly in terms of having both mechanical strength, dimensional accuracy and electrical properties.

A particularly preferred combination is an average fiber length of 30 to 500 μm.
Is a combination of the above glass fiber and an inorganic powdery substance having an aspect ratio of 5 or less.

When using these fillers, it is desirable to use a sizing agent or a surface treatment agent if necessary. Examples of this are functional compounds such as epoxy compounds, isocyanate compounds, silane compounds and titanate compounds. These compounds may be subjected to a surface treatment or a converging treatment in advance, or may be added at the same time when the material is prepared.

The amount of the inorganic filler used as the component (C) is 0 to 400 per 100 parts by weight of the polyarylene sulfide resin (A).
Parts by weight, preferably 10 to 250 parts by weight. If the amount is too small, the mechanical strength is inferior. If the amount is too large, the molding operation becomes difficult, and the mechanical strength of the molded article also has a problem.

Next, as the component (D) of the composition of the present invention, a silane compound that is used in combination with the components (A), (B), and (C) is aminoalkoxysilane, epoxyalkoxysilane, or mercaptoalkoxysilane. And one or more alkoxysilanes selected from vinylalkoxysilanes.

As the aminoalkoxysilane, any silane compound having one or more amino groups and two or three alkoxy groups in one molecule is effective, and for example, γ-aminopropyltriethoxysilane, γ -Aminopropyltrimethoxysilane, γ-aminopropylmethyldiethoxysilane, γ-aminopropylmethyldimethoxysilane, N-β (aminoethyl) -γ-aminopropyltriethoxysilane, N-β (aminoethyl)-
γ-aminopropyltrimethoxysilane, N-β (aminoethyl) -γ-aminopropylmethyldiethoxysilane, N-β (aminoethyl) -γ-aminopropylmethyldimethoxysilane, N-phenyl-γ-aminopropyltrimethoxysilane Ethoxysilane, N-phenyl-γ-aminopropyltrimethoxysilane and the like can be mentioned.

Epoxyalkoxysilane has one or more epoxy groups in one molecule and has two or three alkoxy groups.
Any silane compound having one silane compound is effective, for example, γ-glycidoxypropyltrimethoxysilane, β- (3,4-epoxycyclohexyl) ethyltrimethoxysilane, γ-glycidoxypropyltriethoxysilane, etc. Is raised.

As the mercaptoalkoxysilane, any silane compound having one or more mercapto groups in one molecule and two or three alkoxy groups is effective, and for example, γ-mercaptopropyltrimethoxysilane, γ -Mercaptopropyltriethoxysilane and the like.

As the vinylalkoxy silane, any silane compound having one or more vinyl groups and two or three alkoxy groups in one molecule is effective, and examples thereof include vinyltriethoxysilane and vinyltrimethoxy. Silane and vinyltris (β-methoxyethoxy) silane.

The amount of the alkoxysilane used in the present invention is 5 parts by weight or less, preferably 0.01 to 3 parts by weight, per 100 parts by weight of the polyarylene sulfide resin. If it is too small, the intended effect is small, and if it is too large, the mechanical properties are deteriorated, which is not preferable.

The compounding of the component (D) is effective not only for improving the moldability and mechanical properties, but also for discoloration due to the molding process and discoloration of the molded product with time at high temperatures when used in combination with the component (B). However, it was recognized that even more effects were exhibited.

Further, as the base resin of the present invention, it is possible to use a small amount of another thermoplastic resin in combination as long as the purpose is not hindered. Any other thermoplastic resin may be used as long as it is a thermoplastic resin that is stable at high temperatures. For example, polyethylene terephthalate, aromatic polyester such as polybutylene terephthalate and an aromatic dicarboxylic acid and diol or oxycarboxylic acid, polyamide, polycarbonate, ABS, polyphenylene oxide, polyalkyl acrylate, polyacetal, polysulfone, polyether sulfone, poly Examples thereof include ether imide, polyether ketone, and fluorine resin. These thermoplastic resins can be used as a mixture of two or more kinds.

Furthermore, in the composition of the present invention, known substances generally added to thermoplastic resins and thermosetting resins, that is, stabilizers such as antioxidants and ultraviolet absorbers, antistatic agents, release agents,
Flame retardants, flame retardant aids, colorants such as dyes and pigments, lubricants, nucleating agents, and the like can be appropriately added in combination depending on the required performance.

The preparation of the polyarylene sulfide resin composition of the present invention can be performed by equipment and a method generally used for preparing a synthetic resin composition. That is, necessary components can be mixed, kneaded using a single-screw or twin-screw extruder, and extruded into molding pellets. A method of mixing and molding a part of the necessary components as a masterbatch, In order to improve the dispersion and mixing of the components, any or all of the polyarylene sulfide resin may be pulverized, mixed, and melt-extruded.

[Examples] The present invention will be described in more detail with reference to Examples below.
The present invention is not limited to these.

Examples 1 to 11 and Comparative Examples 1 to 24 Polyphenylene sulfide resin (manufactured by Kureha Chemical Industry Co., Ltd., trade name “Fortron KPS”) was used in Tables 1 to 11.
The additives shown in Table 3 were added in the amounts shown in Tables 1 to 3 and premixed with a Henschel mixer for 5 minutes. Further, commercially available glass fibers (diameter 13 μm, length 3 mm) and calcium carbonate were added in the amounts shown in the table and mixed for 2 minutes with a blender. The mixture was extruded at a cylinder temperature of 310 ° C., and pellets of a polyphenylene sulfide resin composition were obtained. Had made.

Next, the cylinder temperature was 320 ° C and the mold temperature was 1 with an injection molding machine.
A flat plate test piece having a thickness of 3 mm and a size of 50 mm × 70 mm was molded at 50 ° C. and the hue of the molded product was measured using a color difference meter manufactured by Nippon Denshoku Industries Co., Ltd.

Further, the degree of black streak or mottled discoloration generated on the surface of the molded article was also observed. Further, the resin melted during the injection molding was free-flowed, and the amount of gas generated from the molten resin was evaluated. Further, a tensile test piece was molded using an injection molding machine at a cylinder temperature of 320 ° C. and a mold temperature of 150 ° C. in accordance with ASTM D638, and the strength and elongation were measured. The results are shown in Tables 1 to 3.

Tables 1-3 (Note 1) F: (C ₁₀ H ₂₁ O ₃ P (Note 2) G: γ-aminopropyltriethoxysilane H: γ-glycidoxypropyltrimethoxysilane I: γ-mercaptopropyltrimethoxysilane J: vinyltrimethoxysilane [ EFFECTS OF THE INVENTION As is clear from the above description and Examples, the polyarylene sulfide resin composition of the present invention is significantly improved in discoloration as compared with the conventional polyarylene sulfide resin composition, has a high whiteness, and has a stripe shape. In addition, a molded article having a good surface condition with less occurrence of mottled discoloration can be obtained, and has excellent heat resistance, and hardly generates any evaporation gas or decomposition gas at the time of extrusion or molding, and there is almost no obstacle due to these. Excellent in mechanical and physical properties.

 ────────────────────────────────────────────────── ─── Continuation of the front page (72) Inventor Andrew Auerbach, Orchard Lane, Livingston, Essex, NJ 23 (56) References JP-A-63-159470 (JP, A) JP-A-64-79260 (JP, A) JP-A-64-63115 (JP, A) JP-A-64-89208 (JP, A)

Claims (1)

(57) [Claims] 1. An amount of 0.01 to 10 parts by weight of an organic bisphosphite compound represented by the following formula (1): (A) 100 parts by weight of a polyarylene sulfide resin having a substantially linear molecular structure. (However, in the formula, R ₁ and R ₂ are an alkyl group, a substituted alkyl group,
A group selected from an aryl group, a substituted aryl group and an alkoxy group, which may be the same or different. (C) Inorganic filler 0 to 400 parts by weight (D) At least one alkoxysilane selected from aminoalkoxysilane, epoxyalkoxysilane, mercaptoalkoxysilane, vinylalkoxysilane
A polyarylene sulfide resin composition comprising 0.01 to 5 parts by weight.