JP3118885B2 - Polyphenylene 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 polyphenylene sulfide resin composition having good surface smoothness, adhesion to a primer and the like and excellent moldability in post-processing such as coating and metal deposition. It is about.

[0002]

2. Description of the Related Art Polyphenylene sulfide resin (hereinafter, referred to as polyphenylene sulfide resin)
PPS) is used as an engineering plastic having excellent strength, heat resistance, flame retardancy, and chemical resistance, mainly for injection molding, for electric / electronic parts, automobile parts, precision machine parts, and the like.

However, the use of PPS resin has expanded,
Combination with various other materials and application to functional parts that require surface post-processing have been studied. PPS resin has low adhesion to metal or epoxy resin, When it is attempted to modify the composition by vapor deposition or the like, the problem is that the adhesion to the primer is low. A method of adding a monoepoxy compound to a PPS resin for the purpose of improving the adhesion of such a PPS resin to a metal or an epoxy resin (for example, see JP-A-6
4-65171), a method of adding a specific silane compound (for example, JP-A-1-101366),
Method of adding specific wax to PS resin
No. 272063) has been proposed. However, in the method of adding these specific organic compounds, in the melt molding process of the PPS resin, some of the additives are liable to volatilize or decompose, and the effect of improving the adhesiveness is unstable. -Unsatisfactory effects such as coloring appear, etc., are not always satisfactory.

[0004]

Accordingly, the present invention relates to a PP
PPS resin with excellent surface smoothness, stable and good adhesion to primers, etc., without impairing the excellent properties inherent to S resin, and without problems such as burning or coloring of molded products It is an object to obtain a composition.

[0005]

In other words, the present invention relates to a method for preparing a polyphenylene sulfide resin based on 100 parts by weight of phosphorus phosphite.
Lithium oxide, sodium phosphite, magnesium phosphite
At least one selected from calcium and calcium phosphite
There is provided a polyphenylene sulfide resin composition obtained by adding compounding phosphite metal salts 0.05 to 10 parts by weight of the seed.

[0006] The polyphenylene sulfide resin (A) used in the present invention refers to a repeating unit represented by the structural formula (I).

[0007]

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It is a polymer containing 70 mol% or more, more preferably 90 mol% or more. When the repeating unit is less than 70 mol%, heat resistance is undesirably deteriorated.
Also, the PPS resin can constitute less than 30 mol% of the repeating unit with a repeating unit having the following structural formula.

[0009]

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The melt viscosity of the PPS resin used in the present invention is not particularly limited as long as melt kneading is possible.
0 to 20,000 poise (320 ° C., shear rate 10 sec)
c ^-1 ) is used.

[0011] Such PPS resin is usually prepared by a known method,
A method for obtaining a polymer having a relatively small molecular weight described in JP-B-45-3368 or JP-B-52-1224.
The polymer can be produced by a method for obtaining a polymer having a relatively high molecular weight described in Japanese Patent Application Laid-Open No. 0-73 and JP-A-61-7332. In the present invention, the PPS resin obtained as described above is crosslinked / polymerized by heating in air, washed with an organic solvent, hot water, an aqueous acid solution, etc., and activated by a functional group-containing compound such as an acid anhydride or isocyanate. Of course, it is also possible to use after performing various treatments such as conversion.

Specific examples of the metal phosphite used in the present invention include lithium phosphite, sodium phosphite ,
Select from sub-magnesium phosphate and phosphorous acid calcium
It includes at least one kind Barre, but among these, sodium phosphite particularly preferred. Although the mechanism of the improvement of the adhesion of the PPS resin to the coating or the metal deposition primer by adding the metal phosphite is not always clear, the crystallization characteristics and orientation of the surface of the PPS resin molded article can be improved by the addition of the metal phosphite. There is a possibility that a subtle change is given to the behavior. Another feature of the present invention is that the addition of the metal phosphite also has the effect of greatly suppressing the occurrence of "burn" and coloring in the step of melt-molding the PPS resin.

In the present invention, the amount of the metal phosphite is in the range of 0.05 to 10 parts by weight, preferably 0.1 to 5 parts by weight, based on 100 parts by weight of the PPS resin. When the addition amount of the metal phosphite is less than 0.05 part by weight, the effect of improving the adhesion and suppressing the deterioration is insufficient, which is not preferable.
On the other hand, if the amount exceeds 10 parts by weight, the mechanical strength of the PPS resin composition is impaired, which is not preferable.

In the present invention, the fibrous and / or granular reinforcing material is not an essential component, but if necessary, PPS may be used.
It can be blended in a range not exceeding 400 parts by weight with respect to 100 parts by weight of the resin, and usually improves the strength, rigidity, heat resistance and dimensional stability by blending in a range of 10 to 200 parts by weight. It is possible to plan.

Examples of the fibrous reinforcing material include glass fiber, alumina fiber, silicon carbide fiber, ceramic fiber, asbestos fiber, gypsum fiber, metal fiber and carbon fiber.

Examples of the granular reinforcing material include silicates such as wollastenite, sericite, kaolin, mica, clay, bentonite, asbestos, talc, alumina silicate, alumina, silicon chloride, magnesium oxide, zirconium oxide, and titanium oxide. Metal oxides, calcium carbonate, magnesium carbonate, carbonates such as dolomite,
Sulfates such as calcium sulfate and barium sulfate, glass and
Examples include beads, boron nitride, silicon carbide and silica, which may be hollow. These reinforcements are 2
More than one kind can be used in combination, and if necessary, can be used after being pretreated with a coupling agent such as a silane-based or titanium-based coupling agent.

The method for preparing the resin composition used in the present invention is not particularly limited, and a PPS resin, powder of a metal phosphite,
Pellets, crystals and, if necessary, reinforcement are dry-blended using a ribbon blender, Henschel mixer, V-blender, etc., and then melted using a Banbury mixer, mixing roll, single or twin screw extruder and kneader, etc. A method of kneading may be used. Above all, a typical method is melt kneading using a single-screw or twin-screw extruder having a sufficient kneading force.

The resin composition comprising the PPS resin and the metal phosphite used in the present invention may contain an antioxidant, a heat stabilizer, a lubricant, a crystal, and the like as long as the effects of the present invention are not impaired. Conventional additives such as a nucleating agent, an ultraviolet ray inhibitor, a colorant, and a flame retardant can be added. Further, for the purpose of controlling the degree of crosslinking of the PPS resin, a conventional peroxide agent and JP-A-59-1
A crosslinking accelerator such as a metal thiophosphinate described in JP-A-31650 or JP-A-58-204045;
It is also possible to incorporate a crosslinking inhibitor such as dialkyltin dicarboxylate and aminotriazole described in JP-A-58-204046 and JP-A-58-204046.

Furthermore, the PPS resin composition of the present invention can be used as long as the effects of the present invention are not impaired, provided that the polyamide, polyphenylene oxide, polysulfone, polyethylene tetrafluoride, polyetherimide, polyamideimide, polyimide, polycarbonate, polyethersulfone are used. , Polyether ketone, polyether ether ketone, epoxy resin, phenol resin, polyethylene, polystyrene, polypropylene, ABS resin, polyester, polyamide elastomer, polyester elastomer, and the like.

[0020]

The present invention will be described in more detail with reference to the following examples. The tensile strength, bending strength, heat deformation temperature, coating film adhesion, and molded article color tone described in the examples and comparative examples were measured by the following methods.

Tensile strength: ASTM D638 Bending strength: ASTM D790 Thermal deformation temperature: ASTM D648 Coating adhesion: 80 at a cylinder temperature of 300 to 320 ° C. and a mold temperature of 130 ° C. using an injection molding machine.
A square plate of × 80 × 3 mm is formed, and a two-part curable urethane paint (Pr. Manufactured by Nippon Bee Chemical Co., Ltd.)
imer RB-291 / TOP R-263) was sequentially spray-coated / baked at 80 ° C. for 40 minutes to form a coating film. Cuts were made in the coating at 1 mm intervals in the vertical and horizontal directions to form a total of 100 gobangs. After a cellophane tape was stuck from above the gobang eyes, the cellophane tape was peeled off, and the number of eyes remaining on the molded piece was counted to give a measure of the coating film adhesion.

Color tone of molded piece: Color tone (L
Value) was measured using a SM-3 color computer manufactured by Suga Test Instruments Co., Ltd.

Example 1 100 parts by weight of PPS powder (M2588 manufactured by Toray Phillips Vitrolium Co.) and 0.5 part by weight of sodium phosphite were dry blended, and a cylinder temperature of 300 ° C. and a screw rotation were performed using a 30 mm φ twin screw extruder. The mixture was melt-kneaded under conditions of several hundred rpm to form pellets. After the pellets were dried with hot air at 130 ° C. for 4 hours, the cylinder temperature was set to 300 ° C. and the mold temperature was set to 13 using an injection molding machine.
Various test pieces and square plates were formed at 0 ° C. The properties measured using these molded products are as shown in Table 1, and it was found that the resin composition obtained here had good adhesion to the coating film and was of extremely high practical value.

Comparative Example 1 Extrusion pelletization of PPS was carried out in exactly the same manner as in Example 1 except that sodium phosphite was not used, and the properties of the obtained molded product were measured. The film adhesion was remarkably low and the color tone was inferior.

Example 2 100 parts by weight of the PPS powder used in Example 1 and 1.0 part of magnesium phosphite were dry-blended, and then extruded, kneaded and injection-molded in the same manner as in Example 1 to obtain various molded pieces. I got The properties of the molded pieces obtained here are as shown in Table 1, and both the coating film adhesion and the color tone were excellent.

[0026]

[Table 1]

Example 3 100 parts by weight of the PPS powder used in Example 1 and a fiber diameter of about 9
After dry blending 65 parts by weight of glass fiber of 65 μm and 2 parts by weight of sodium phosphite with a Henschel mixer, the mixture was fed to a feeder of a 40 mmφ single screw extruder and melt-kneaded at a cylinder temperature of 320 ° C. and a screw rotation speed of 80 rpm. And pelletized. 14 pellets
After drying with hot air at 0 ° C. for 3 hours, various molded pieces were molded using an injection molding machine under the conditions of a cylinder temperature of 320 ° C. and a mold temperature of 150 ° C. The properties of these molded pieces are as shown in Table 2, and it was found that the reinforced PPS resin composition obtained here was also excellent in coating film adhesion and color tone and of high practical value.

Examples 4 to 6 Extrusion kneading and injection molding were carried out in the same manner as in Example 3 by changing the types and amounts of the PPS powder, phosphite and filler, and various properties shown in Table 2 were obtained. Was obtained. The resin compositions obtained here were all excellent in adhesion, mechanical properties, and the like.

[0029]

[Table 2]

[0030]

According to the present invention, the resin composition comprising the PPS resin, the phosphite and, if necessary, the reinforcing filler has excellent coating film adhesion and surface smoothness, and can be used for coating or metal deposition. Useful for parts that require processing.

──────────────────────────────────────────────────続 き Continued on front page (58) Field surveyed (Int. Cl. ⁷ , DB name) C08L 81/00-81/02 C08K 3/32

Claims (2)

(57) [Claims] 1. Lithium phosphite, sodium phosphite , 100 parts by weight of polyphenylene sulfide resin ,
Select from magnesium phosphite and calcium phosphite
At least one metal phosphite salt 0.05 to 10
A polyphenylene sulfide resin composition obtained by adding and blending parts by weight. 2. A polyphenylene sulfide resin composition comprising the polyphenylene sulfide resin composition according to claim 1 and 400 parts by weight or less of a fibrous and / or granular reinforcing material added to 100 parts by weight of the polyphenylene sulfide resin. Stuff.