JP3038794B2 - Resin composition - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION <Industrial Application Field> The present invention relates to a thermoplastic resin composition having excellent properties such as strength, heat resistance, dimensional stability, chemical resistance, flame retardancy, and melt fluidity. More specifically, a resin composition comprising a polyphenylene sulfide resin (hereinafter abbreviated as PPS resin) and a polyarylene sulfide sulfone resin (hereinafter abbreviated as PASS resin) having a specific molecular weight distribution and melt viscosity behavior. It is.

<Prior art> PPS resin has a high melting point and excellent melt moldability, moisture resistance, and flame retardancy, and its demand is increasing in the fields of electric / electronics, automobiles, and general machinery. .
However, PPS resin is hard and brittle, and its glass transition point is as low as around 90 ° C. Therefore, strength and heat resistance of the resin alone are insufficient, and ordinary use is made of glass fiber, carbon fiber, and other inorganic fillers. Limited to those reinforced by In order to improve the heat resistance and strength, which are insufficient with PPS resin alone, a method of blending an amorphous polymer with a high glass transition point has been studied, and so far PPS resin and polyphenylene oxide resin have been studied. (For example, JP-B-56-34032) and a method of blending a PPS resin and polycarbonate (for example, JP-B-53-34032).
No. 13468), a method of blending a PPS resin with polysulfone or polyethersulfone (for example, see JP-A-59-16).
JP-A-4360 or JP-A-61-34068), a method of blending a PPS resin with a polythioether sulfone or a polyether sulfone / polythioether sulfone copolymer (eg, JP-A-63-256653) is proposed. Have been. However, the resin compositions obtained by these conventional techniques have insufficient chemical resistance and flame retardancy due to the extremely low chemical resistance and flame retardancy of the polymer blended with the PPS resin, Further, at present, a material that is truly useful as a molding resin material has not yet been obtained, such as a material having low mechanical strength due to poor compatibility between a PPS resin and a polymer.

<Problems to be solved by the invention> Therefore, the present inventors have developed a combination of a PPS resin and an amorphous polymer to provide mechanical strength, heat resistance, dimensional stability, chemical resistance, flame retardancy, melt fluidity, etc. As a result of intensive studies to obtain a resin composition that satisfies all of the properties required for resin molding materials, a resin composition consisting of a PPS resin having a specific molecular weight distribution and melt viscosity behavior, and a polyarylene sulfide sulfone resin The inventors have found that the above objects can be solved at once, and have reached the present invention.

<Means for Solving the Problems> That is, the present invention provides (A) a number average molecular weight (（) and a weight average molecular weight (▲) determined by gel permeation chromatography using 1-chloronaphthalene as a solvent.
Has a molecular weight distribution satisfying the following formula (1), and AS
The melt flow rate measured by a method according to TM D1238-86 (315.5 ° C., 5,000 g load) is a polyphenylene sulfide resin satisfying the following formulas (2) and (3):
It is intended to provide a resin composition comprising 1% by weight and (B) 5 to 99% by weight of a polyarylene sulfide sulfone resin.

▲ ▼ / ▲ ▼ <10 (1) MF ₅ <1000 g / 10 min (2) 50 <(MF ₅ / MF ₁₅ ) × 100 <120 (3) (where MF ₅ and MF ₁₅ each have a residence time of 5 minutes) And the melt flow rate value at 15 minutes.) The PPS resin used in the present invention has the structural formula At least 70 mol%, more preferably
It is a polymer containing 90 mol% or more, and its molecular weight distribution and melt viscosity behavior are specified as described above.

PPS is generally a polymer having a relatively small molecular weight obtained by the production method represented by Japanese Patent Publication No. 45-3368 and an essentially linear polymer obtained by the production method represented by Japanese Patent Publication No. 52-12240. There are relatively high molecular weight polymers,
In the polymer obtained by the method described in JP-B No. 45-3368, the degree of polymerization is increased by heating in an enzyme atmosphere after polymerization or by adding a crosslinking agent such as peroxide and heating. Sometimes used.

However, among such various types of PPS, those that can provide useful resin compositions satisfying various requirements such as heat resistance, strength, and dimensional stability as in the present invention must be extremely specified. Must. That is, for example, even if a relatively low molecular weight polymer obtained by the method disclosed in the above-mentioned JP-B No. 45-3368 is used and the degree of polymerization is increased by a heating reaction in the presence of an enzyme, a partially crosslinked structure is obtained. In some cases, only a hard and brittle composition can be obtained, and the molecular weight distribution and melt viscosity behavior of PPS are as shown in the formula (1) according to the present invention.
(2) (3) By using a specific PPS resin that satisfies all requirements, a high-performance resin composition having high practical value can be obtained for the first time.

In addition, PPS can constitute less than 30 mol% of the repeating unit with a repeating unit having the following structural formula.

The PPS used in the present invention is preferably produced through the above-mentioned polymerization step and then subjected to an acid treatment, a hot water treatment or a washing with an organic solvent.

Examples of the PPS resin preferably used in the present invention include M2888, M2588, E2280, E2480 manufactured and sold by Toray Phillips Petroleum Co., but those limited to these products are Absent.

The polyarylene sulfide sulfone resin (PASS resin) of the component (B) used in the present invention is a polymer mainly comprising a structural unit represented by the following formula (3),
Such a PASS resin can be produced, for example, by the method described in JP-B-52-155699 or JP-B-52-155700.

Here, Ar ¹ and Ar ² are each a divalent aromatic hydrocarbon group, for example, p-phenylene group, m-phenylene group, o-phenylene group, methyl-substituted phenylene group, ethyl-substituted phenylene group, dimethyl-substituted group Examples include a phenylene group, a trimethyl-substituted phenylene group, a tetramethyl-substituted phenylene group, a naphthylene group, and an alkyl-substituted naphthylene group. Of these, p- or m-phenylene groups and naphthylene groups are preferred, and particularly preferred are polymers in which both Ar ¹ and Ar ² are p-phenylene groups. The degree of polymerization of the PASS resin is not particularly limited, and may be a method according to ASTM D1238-86 (340 ° C., 5,000
Melt flow rate measured at 0 g load)
One having a range of 0 (g / 10 minutes), preferably 1 to 800 (g / 10 minutes) can be used.

In the present invention, the composition ratio of PPS resin and PASS resin is PPS
/ PASS = 95-1 / 5-99% by weight, preferably 90%
33/10 to 97% by weight, more preferably 80 to 5/20 to 95% by weight. When the amount of PPS resin exceeds 95% by weight,
The heat resistance and the dimensional stability of the obtained resin composition are insufficient, which is not preferable. On the other hand, if the amount of the PASS resin exceeds 99% by weight, the melt flowability of the resin composition, that is, the moldability is lowered, which is not preferable.

The method for preparing the resin composition of the present invention is not particularly limited, and PPS
Resin and PASS resin powder, pellets, and flakes 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, kneader, etc. A method of kneading may be used. Among them, a method of melt-kneading using a single-screw or twin-screw extruder having a sufficient kneading force is typical.

In addition, the PPS resin composition used in the present invention includes an antioxidant, a heat stabilizer, a lubricant, a crystal nucleus material, an ultraviolet ray inhibitor, a coloring agent, a flame retardant and the like as long as the effects of the present invention are not impaired. Additives and small amounts of various polymers can be added, and further, for the purpose of controlling the degree of cross-linking of PPS, ordinary peroxides and metal salts of thiophosphinic acid described in JP-A-59-131650, etc. Crosslinking accelerator or JP-A-58-2040
It is also possible to incorporate a crosslinking inhibitor such as dialkyltin dicarboxylate and aminotriazole described in JP-A No. 45-205 and JP-A-58-204046.

In the present invention, the fibrous and / or granular reinforcing agent is not an essential component, but if necessary, can be blended in a range not exceeding 400 parts by weight relative to the total 100 parts by weight of the PPS resin composition. Yes, it is possible to improve strength, rigidity, heat resistance, dimensional stability and the like by blending usually in the range of 10 to 300 parts by weight.

Examples of such a fibrous reinforcing agent include glass fiber, alumina fiber, silicon carbide fiber, ceramic fiber, asbestos fiber, masonry fiber, inorganic fiber such as metal fiber, and carbon fiber.

Examples of the granular reinforcing agent include silicates such as walasteinite, sericite, kaolin, mica, clay, bentonite, asbestos, talc, and alumina silicate, and metal oxides such as alumina, silicon chloride, magnesium oxide, zirconium oxide, and titanium oxide. Substances, carbonates such as calcium carbonate, magnesium carbonate and dolomide, sulfates such as calcium sulfate and barium sulfate, glass beads, boron nitride, silicon carbide and silica, and may be hollow. Two or more of these reinforcing agents can be used in combination, and if necessary, can be used after being pretreated with a silane-based or titanium-based coupling agent.

<Example> Hereinafter, the present invention will be described in more detail with reference to examples. In addition, various characteristics described in Examples, Reference Examples, and Comparative Examples were measured as follows.

Tensile properties: ASTM D638 Bending properties: ASTM D790 Izod impact strength: ASTM D256 Heat deformation temperature (18.6 kg f / cm ² load): ASTM D648 Melt flow rate of PPS resin and composition: Measurement temperature 3
The measurement was performed at 15.5 ° C. and a load of 5,000 g according to a method according to ASTM-D1238-86. The melt flow rate value for a residence time of 5 minutes was determined by setting the preheat time to 5 minutes, and the melt flow rate value for a residence time of 15 minutes was determined by setting the preheat time to 15 minutes.

Melt flow rate of polyarylene sulfide sulfone resin: ASTM-D1238, measuring temperature 340 ° C, load 5,000g
It measured by the method according to -86.

Molecular weight and molecular weight distribution: Using a gel permeation chromatograph manufactured by Waters, and published in Polymers, Vol. 44 (1987), February issue.
It was measured according to the method disclosed on pages 139-141.

Flame retardancy: UL-94 Reference Example 1 Table 1 shows the PPS resins used in the examples and comparative examples and their characteristic values.

1) Manufactured by Toray Phillips Petroleum 2) Manufactured by Philips Reference Example 2 3.26 kg of sodium sulfide (25 mol, including 40% crystallization water), 10 g of sodium hydroxide and N-methylpyrrolidone (hereinafter abbreviated as NMP) in an autoclave. After charging 7.9 kg and p-dichlorodiphenylsulfone 7.18 kg (25 mol), the system was purged with nitrogen gas, and heated and reacted at 200 ° C. for 5 hours under pressure while stirring with a stirrer. The reaction product was washed 5 times with hot water at 90 ° C., and then dried under reduced pressure at 80 ° C. for 24 hours to obtain an amorphous polyarylene sulfide having a melt flow rate of 40 g / 10 minutes (340 ° C.) and a glass transition point of 210 ° C. 5.9 kg of a sulfone resin (PASS-1) was obtained and used in the following Examples.

Reference Example 3 The same procedure as in Reference Example 2 was carried out except that 10 kg of sulfolane was used instead of NMP used in Reference Example 2, and a heating reaction / polymer recovery / washing operation was performed.
5.5 kg of a polyarylene sulfide sulfone resin (PASS-2) having 0 g / 10 min (340 ° C.) was obtained and used in the following Examples.

Example 1 PPS-2 bulk powder 1.8 kg (60% by weight) and PASS-1 bulk powder 1.
After 2 kg (40% by weight) was dry-blended using a Henschel mixer, the mixture was fed to a feeder of a 30 mmφ twin screw extruder, melt-kneaded at a cylinder temperature of 340 ° C., the molten gut was cooled with water, and pelletized with a pelletizer. After the pellets were dried with hot air at 140 ° C. for 4 hours, injection molding was performed under the conditions of a molding temperature of 340 ° C. and a mold temperature of 150 ° C. to obtain various test specimens having good appearance. The characteristics of this molded piece are as shown in Table 2, and it was found that the heat resistance, strength and impact resistance were good and the fluidity of the composition was high, so that it was extremely practical.

Comparative Example 1 PPS-2 bulk powder alone was pelletized and subjected to injection molding and property measurement in the same procedure as in Example 1. As a result, the heat deformation temperature was as low as 124 ° C., and the heat resistance was insufficient. .

Comparative Example 2 PASS-1 bulk powder alone was pelletized, and injection molding was performed in the same procedure as in Example 1. However, since the fluidity was insufficient, molding of a thin-walled test piece was particularly difficult. Was.

Comparative Example 3 Except that PPS-3 was used in place of PPS-2 used in Example 1, kneading, pelletizing, and injection molding were performed in exactly the same manner as in Example 1 to obtain a molded piece having a good appearance. However, this product had a very low notched Izod impact value of 5 kgf · cm / cm ² due to the low degree of polymerization of PPS-3, and was not practical.

Comparative Example 4 Kneading and injection molding were performed in exactly the same manner as in Example 1 except that PPS-4 was used instead of PPS-2 used in Example 1. However, due to the instability of melt retention of PPS-4, thickening at the time of melt retention is large, and stable injection molding is difficult, and the notched Izod impact strength of the obtained molded piece is also 7 kgfcm. / cm ² was insufficient.

Examples 2 to 4 Extrusion kneading and injection molding were carried out in the same manner as in Example 1 except that the types and amounts of the PPS resin and PASS resin were changed, and in each case, a molded piece having a good appearance was stably obtained. Was completed. The characteristic values of these molded pieces are as shown in Table 2, and all of them were excellent in heat resistance, moldability, strength and the like in a well-balanced manner.

Examples 5 to 8 A PPS resin, a PASS resin and an inorganic reinforcing material were blended in the proportions shown in Table 2, then kneaded at 340 ° C. using a 40 mmφ, L / D = 25 single screw extruder, and then pelletized. Thereafter, injection molding was performed under the same conditions as in Example 1. The properties of the molded pieces obtained here are as shown in Table 2, and all of them were of high practical value.

<Effect of the Invention> By selecting a PPS resin having a specific molecular weight distribution and a melt viscosity behavior as a PPS resin and combining it with an amorphous PASS resin having a high glass transition point, heat resistance, strength,
A resin composition having excellent chemical resistance, flame retardancy, and moldability was obtained. This resin composition is suitable for applications such as electric / electronic parts, automobile parts, and general mechanical parts.

(56) References JP-A-63-265653 (JP, A) JP-A-63-245464 (JP, A) JP-A-57-205425 (JP, A) (58) Fields investigated (Int) .Cl. ⁷ , DB name) C08L 81/00-81/02 C08L 81/06

Claims (1)

(57) [Claims] (A) The ratio of the number average molecular weight (▲) to the weight average molecular weight (▲) determined by gel permeation chromatography using 1-chloronaphthalene as a solvent satisfies the following formula (1). Has a molecular weight distribution and ASTM D123
95-1% by weight of a polyphenylene sulfide resin having a melt flow rate measured by a method according to 8-86 (315.5 ° C., 5,000 g load) satisfying the following formulas (2) and (3) and (B) polyarylene sulfide Sulfone resin 5
A resin composition comprising 99% by weight. ▲ ▼ / ▲ ▼ <10 (1) MF ₅ <1000 g / 10 min (2) 50 <(MF ₅ / MF ₁₅ ) × 100 <120 (3) (where MF ₅ and MF ₁₅ each have a residence time of 5 And the melt flow rate values at 15 and 15 minutes.)