JP3019108B2 - Resin composition - Google Patents

Description

The present invention relates to a specific polyphenylene sulfide containing a carboxyl group and / or a metal salt thereof and a glycidyl ester of α-olefin / α, β-unsaturated acid. The present invention relates to a resin composition comprising an olefin-based copolymer, and more particularly to a resin composition exhibiting excellent properties of heat resistance, solvent resistance and toughness.

[Problems to be Solved by Related Art and Invention] Polyphenylene sulfide is known as a high-performance resin exhibiting excellent properties such as heat resistance, flame retardancy, chemical resistance, moldability, and electrical properties. Are widely used in applications such as electric / electronic parts and automobile parts.

Polyphenylene sulfide is blended with fibrous reinforcing materials such as glass fiber and carbon fiber, and inorganic fillers such as talc, clay and mica to provide strength, rigidity, heat resistance, toughness,
Performance such as dimensional stability can be greatly improved.
However, polyphenylene sulfide has serious drawbacks such as poor ductility and fragility as compared with engineering plastics such as nylon, polycarbonate, polybutylene terephthalate, and polyacetal. This limits its application to many applications.

Conventionally, as a technique for improving the toughness and impact resistance of polyphenylene sulfide, blending of a flexible polymer has been frequently performed. For example, a method of mixing an olefin copolymer of α-olefin / α, β-unsaturated acid with polyphenylene sulfide (JP-A-2-123160)
JP-A-58-154757, JP-A-59-152953, etc.) and a method of mixing an olefin-based copolymer composed of a glycidyl ester of α-olefin / α, β-unsaturated acid. Is disclosed. However, the molecular chain of ordinary polyphenylene sulfide is poor in reactivity,
Even if a reactive olefin copolymer containing an epoxy group is added, the adhesion to the interface with polyphenylene sulfide is insufficient, and the effect of improving the impact properties is not sufficiently obtained. There is a problem that the heat resistance and the solvent resistance of the obtained blend material are reduced.

On the other hand, compositions using polyphenylene sulfide treated by various methods to improve the adhesion of the interface between polyphenylene sulfide and a flexible polymer are disclosed. For example, α-olefin-based copolymers obtained by graft copolymerizing an unsaturated carboxylic acid or an anhydride thereof with an acid-treated and washed polyphenylene sulfide (Japanese Patent Application Laid-Open No. Sho 62-169854) and α-olefins Composition containing an olefin copolymer composed of a glycidyl ester of an α / β-unsaturated acid (Japanese Patent Laid-Open No. 153343/1987), thermoplastic resin containing amino group and / or amide group-containing polyphenylene sulfide A composition containing an elastomer (JP-A-61-207462, etc.) is disclosed. However, even with these compositions, the effect of improving the impact properties is insufficient.

Therefore, the present inventors have conducted intensive studies to improve the adhesion at the interface between polyphenylene sulfide and the olefin copolymer, and to obtain a resin composition having a remarkable effect of improving impact characteristics and toughness. By blending a specific olefin-based copolymer with polyphenylene sulfide resin, it is possible to increase the adhesion at the interface, and it was found that a blend material that solved the above-mentioned problems of the prior art was provided, and the present invention was completed. I came to.

[Means for Solving the Problems] The present invention relates to (a) a melt viscosity of 200 poise or more, and 0.1 to 5 mol% of a carboxyl group and / or a metal salt thereof.
(Per phenyl sulfide unit) 60 to 99.5% by weight of polyphenylene sulfide, and (b) 40 to 0.5% by weight of an olefin copolymer composed of glycidyl ester of α-olefin / α, β-unsaturated acid. A characteristic polyphenylene sulfide resin composition.

The content of the carboxyl group and / or the metal salt thereof in the carboxyl group and / or the metal salt-containing polyphenylene sulfide used in the present invention is preferably 0.1 to 5 mol% (per phenyl sulfide unit). Particularly preferably
0.1 to 3 mol%. The carboxyl group of polyphenylene sulfide and / or its metal salt content is 0.1 mol%
If it is less than 5%, the desired improvement effect cannot be obtained, and if it exceeds 5 mol%, the mechanical strength decreases, which is not preferable.

Further, the polyphenylene sulfide containing a carboxyl group and / or a metal salt thereof used in the present invention has a structural unit of Is preferably 70 mol% or more, particularly preferably 90 mol% or more. Further, if the amount of the structural unit is less than 30 mol%, preferably less than 10 mol%, the m-phenylene sulfide unit o-phenylene sulfide unit Phenylene sulfide sulfone unit Phenylene sulfide ketone unit Diphenylene sulfide units Phenylene sulfide ether unit Or other copolymerized units.

The polyphenylene sulfide containing a carboxyl group and / or a metal salt thereof used in the present invention can be produced by a preferred production method, for example, according to JP-A-64-48828, that is, an alkali metal sulfide and dihalobenzene in an organic amide solvent. At the time of the reaction, it can be produced by a method of performing polymerization in the presence of a carboxyl group and / or an aromatic halide containing a metal salt thereof.

Alkali metal sulfides include lithium sulfide, sodium sulfide, potassium sulfide, rubidium sulfide, cesium sulfide and mixtures thereof, which may be used in the form of hydrates. These alkali metal sulfides are obtained by reacting an alkali metal hydrosulfide with an alkali metal base, and may be prepared in situ prior to the addition of the dihalobenzene into the polymerization system or may be prepared outside the system. Can be used.

Examples of the aromatic halide containing a carboxyl group and / or a metal salt thereof include 2,3-dichlorobenzoic acid, 2,4-dichlorobenzoic acid, 2,5-dichlorobenzoic acid, 2,6-dichlorobenzoic acid, and 3,4. -Dichlorobenzoic acid, 3,5-dichlorobenzoic acid, 2,3,5-trichlorobenzoic acid, 2,4,6-trichlorobenzoic acid, 2,4-dibromobenzoic acid, 2,4,6-tribromobenzoic acid And metal salts thereof, and further, mixtures thereof.

The charged amount of the alkali metal sulfide and the carboxyl group and / or its metal salt-containing aromatic halide is molar ratio of (alkali metal sulfide) :( carboxyl group and / or its metal salt-containing aromatic halide) = 1.00 : 0.10〜30.
A range of 0 is preferred.

As dihalobenzene, p-dichlorobenzene, p-
Examples include dibromobenzene, p-diiodobenzene, m-dichlorobenzene, m-dibromobenzene, m-diiodobenzene, 1-chloro-4-bromobenzene, and the like. The amount of alkali metal sulfide and dihalobenzene charged is preferably in a molar ratio of (alkali metal sulfide) :( dihalobenzene) = 1.00: 0.90 to 1.10.

As the polymerization solvent, a polar solvent is preferable, and particularly, an aprotic organic amide which is stable to an alkali at a high temperature is a preferable solvent. Some examples of organic amides include N,
N-dimethylacetamide, N, N-dimethylformamide, hexamethylphosphoramide, N-methyl-ε-caprolactam, N-ethyl-2-pyrrolidone, N-methyl-2-pyrrolidone, 1,3-dimethylimidazolidinone Dimethylsulfoxide, sulfolane, tetramethylurea and the like and mixtures thereof.

The amount of the organic amide used as a solvent is 3 to 60% by weight, preferably 7 to 60% by weight of the polymer formed by polymerization.
It can be used within a range of 40% by weight. Polymerization is 20
It is carried out with stirring at 0 to 300 ° C, preferably 220 to 280 ° C for 0.5 to 30 hours, preferably 1 to 15 hours.

The polymer obtained by the above method can be cured by a heat treatment in an oxygen atmosphere or a heat treatment with the addition of a peroxide or the like to increase the degree of polymerization. This curing is performed, for example, in an air atmosphere in a temperature range of 200 to 280 ° C.
It is performed by processing for 12 hours.

In particular, in order to obtain a composition having excellent impact properties and toughness, a polyphenylene sulfide polymer containing a carboxyl group and / or a metal salt thereof is dissolved in a non-oxidizing inert gas in an inert gas.
It is preferred to cure at a temperature in the range of 200 ° C to about 280 ° C for 1 to 24 hours.

Examples of the non-oxidizing inert gas that can be used in the present invention include helium, argon, nitrogen, carbon dioxide, water vapor, and the like, and a mixture thereof. Nitrogen is preferable from an economic viewpoint.

The carboxyl group and / or its metal salt-containing polyphenylene sulfide used in the present invention must have a melt viscosity before curing of 200 poise or more, particularly preferably 400 poise or more, and a melt viscosity after heat curing. 800
Preferably it is ~ 30000 poise. Particularly preferably, the melt viscosity after heat curing is from 1,000 to 20,000 poise. If the melt viscosity before heat curing is less than 200 poise or the melt viscosity after heat curing is less than 800 poise, a polyphenylene sulfide composition excellent in toughness may not be obtained, probably because the molecular weight is too low. Further, if the melt viscosity after heat curing exceeds 30,000 poise, the viscosity may be too high and molding may not be performed. The melt viscosity of the carboxyl group and / or its metal salt-containing polyphenylene sulfide was measured using a Koka flow tester (die: 0.5 mm in diameter, 2 mm in length).
The test was performed at 300 ° C. under a load of 10 kg.

The specific olefin-based copolymer used in the present invention is a copolymer composed of an α-olefin and a glycidyl ester of an α, β-unsaturated acid, wherein the α-olefin is ethylene, propylene, butene. -1, etc., and ethylene is preferably used. Α, β
Glycidyl esters of unsaturated acids are represented by the general formula (R represents a hydrogen atom or a lower alkyl group), specifically, glycidyl acrylate, glycidyl methacrylate, glycidyl ethacrylate, and the like. Among them, glycidyl methacrylate is more preferably used. You. Α, in olefin copolymer
The content of the glycidyl ester of β-unsaturated acid is preferably 1 to 30% by weight, particularly preferably 3 to 20% by weight, and if it is less than 1% by weight, the desired improvement effect cannot be obtained. If it exceeds 30% by weight, polyphenylene sulfide is used. When melt mixing with
It is not preferable because extrusion stability and moldability are reduced.
Further, if it is 40 mol% or less in the olefin-based copolymer and the range in which the object of the present invention is not impaired, other copolymerizable unsaturated monomers such as vinyl ethers, vinyl acetate and vinyl propionate. One or more of vinyl esters, acrylic acid and methacrylic acid esters such as methyl, ethyl and propyl, acrylonitrile, styrene and the like may be copolymerized.

The compounding ratio of the constituent components of the resin composition of the present invention is 60 to 99.5% by weight, preferably 80 to 97% by weight, of a carboxyl group and / or its metal salt-containing polyphenylene sulfide resin and α-olefin / α, β-unsaturated. The content is 40 to 0.5% by weight, preferably 20 to 3% by weight, of an olefin copolymer composed of a glycidyl ester of an acid. If the amount of the olefin-based copolymer is less than 0.5% by weight, the desired improvement effect cannot be obtained. If the amount exceeds 40% by weight, not only the excellent heat resistance and solvent resistance of the polyphenylene sulfide itself, but also the melting and kneading are reduced. Gel is sometimes generated, and extrusion stability and moldability are reduced, which is not preferable.

The resin composition of the present invention can be produced by various known methods. Raw material resin is tumbled in advance as dry powder,
A mixture obtained by mixing with a mixer such as a Henschel mixer, a ball mill, a ribbon blender, or the like, or by further curing the mixture by a heat treatment is used. The thus-prepared dry powder or pellets are mixed in a blender or the like, and further melt-mixed to produce a resin composition. In addition, the raw material resin is separately supplied to the melt mixer,
The resin composition may be produced by melt-mixing. Melt mixing is performed using a kneader, Banbury mixer, extruder, etc.
A method such as melting and kneading at a temperature of about 350 ° C. is used.
Although there is no particular limitation on the melt mixing method, it is preferable to use an extruder in consideration of operability.

In addition, the resin composition of the present invention may be a conventionally known fibrous or inorganic powder filler, that is, glass fiber, carbon fiber, silica fiber, alumina fiber, silicon carbide fiber, as long as the object of the present invention is not impaired. Fillers such as zirconia fiber, calcium titanate fiber, wollastonite, calcium sulfate fiber, aramid fiber, wholly aromatic polyester fiber, calcium carbonate, magnesium carbonate, talc,
Fillers such as mica, clay, silica, alumina, kaolin, zeolite, gypsum, calcium silicate, magnesium silicate, calcium sulfate, titanium oxide, magnesium oxide, carbon black, graphite, iron oxide, zinc oxide, copper oxide, etc. Inorganic fillers such as glass beads, glass powder, glass balloons, quartz, quartz glass and the like can also be blended. These fillers can be used in combination of two or more, and if necessary, can be used after being pre-treated with a silane-based or titanium-based coupling agent.

Furthermore, the resin composition of the present invention may be a conventionally known release agent, a lubricant, a heat stabilizer, an antioxidant, an ultraviolet absorber, a crystal nucleating agent, a foaming agent, a rust preventive, as long as the object of the present invention is not impaired. Agent,
One or more ion trapping agents, flame retardants, flame retardant aids, coloring agents such as dyes and pigments, additives such as antistatic agents, waxes and small amounts of other polymers may be used in combination.

The method for adding the additive can be any method. For example, there is a method of adding to the individual resin before or during the formation of the composition, or a method of adding after the formation of the composition and subsequently melting the composition.

EXAMPLES Hereinafter, the present invention will be described specifically with reference to Examples, but the present invention is not limited to these Examples.

Reference Example 1 (Synthesis of carboxyl group-containing polyphenylene sulfide) Internal volume 530 equipped with a stirrer, dehydration tower and jacket
Was charged with 61.1 kg of N-methyl-2-pyrrolidone (hereinafter abbreviated as NMP) 110 and sodium sulfide (purity: 60.2% by weight of Na ₂ S), and heated with a jacket under stirring.
Dehydration was performed through a dehydration tower until the internal temperature reached about 200 ° C. At this time, a distillate of 13.5 mainly consisting of water was distilled off. Then, p-dichlorobenzene (hereinafter p-DCB)
68.0 kg and 0.89 kg of 3,4-dichlorobenzoic acid (p-D
(About 1 mol% added to CB) together with NMP48,
After the temperature was raised to 225 ° C. over 2 hours and reacted at 225 ° C. for 2 hours, the temperature was raised to 250 ° C. over 30 minutes and further reacted at 250 ° C. for 3 hours. At this time, the pressure rose to 10.5 kg / cm ² .

After completion of the reaction, the reaction mixture was transferred to a solvent recovery device equipped with a stirrer, a jacket and a reduced pressure line. At this time, NMP
Added 30. Subsequently, heating under reduced pressure, mainly
A distillate 210 consisting of NMP was distilled off. Then, water 200
After adding and stirring with water slurry at 80 ° C for 15 minutes,
The polymer was recovered by centrifugation. The unreacted 3,4-dichlorobenzoic acid remaining in the filtrate was measured by gas chromatography (GC-12A, manufactured by Shimadzu Corporation), and the conversion of 3,4-dichlorobenzoic acid was 93%.

Further, the polymer was returned to the solvent collector, water 200 was added, and the mixture was heated and stirred at 100 ° C. for 30 minutes. After cooling, the polymer powder was recovered by a centrifuge. This operation was repeated twice.

The obtained polymer was transferred to a jacketed ribbon blender and dried. The carboxyl group-containing polyphenylene sulfide thus obtained is designated as PPS-I.
The melt viscosity of the obtained PPS-I (measured by a Koka type flow tester under a load of 10 kg using a die having a diameter of 0.5 mm and a length of 2 mm at 300 ° C.) was 520 poise.

This PPS-I was transferred to a ribbon blender with a jacket and cured in air at 235 ° C. for 2 hours to obtain a polymer having a melt viscosity of 8,000 poise. The carboxyl group-containing polyphenylene sulfide thus obtained is referred to as PPS-II.

Reference Example 2 (Curing with Non-Oxidizing Inert Gas) Transfer PPS-I to a ribbon blender with jacket,
The temperature was raised to 230 ° C. while flowing nitrogen at a flow rate of 400 / hr under stirring, and curing was performed for 10 hours. Melt viscosity after curing is 16
It was 50 poise. The carboxyl group-containing polyphenylene sulfide thus obtained is referred to as PPS-III.

Reference Example 3 Synthesis of carboxyl group-containing polyphenylene sulfide was carried out using 64.6 kg of p-DCB and 5.36 kg of 3,4-dichlorobenzoic acid (p-DCB).
The procedure was performed in the same manner as in Reference Example 1 except that the amount of DCB was changed to about 6 mol%. The viscosity of the obtained polymer was 370 poise. Unreacted 3,4-dichlorobenzoic acid remaining in the filtrate was measured by gas chromatography, and the conversion of 3,4-dichlorobenzoic acid was 90%.
The polymer was transferred to a jacketed ribbon blender and cured in air at 235 ° C. for 2 hours to obtain a polymer having a melt viscosity of 8,000 poise. The carboxyl group-containing polyphenylene sulfide thus obtained is designated as PPS-IV.

Reference Example 4 (Synthesis of Polyphenylene Sulfide) Synthesis of polyphenylene sulfide was performed in the same manner as in Reference Example 1, except that a carboxyl group-containing aromatic halide was not added. The viscosity of the obtained polymer was 610 poise. The polymer was transferred to a jacketed ribbon blender and cured in air at 235 ° C. for 2 hours to obtain a polymer having a melt viscosity of 8,000 poise. The polymer thus obtained is designated as PPS-V.

Examples 1, 2 PPS-II or PPS-III90% by weight of ethylene / glycidyl methacrylate copolymer (manufactured by Sumitomo Chemical Co., Ltd., BONDFAST ^R E) were mixed with 10 wt%, 300 with a twin-screw extruder
The mixture was melt-kneaded at ℃ and pelletized. The obtained pellets are injection molded at 290 ° C. to prepare a test piece, and the Izod impact strength (measured according to ASTM D-256, with notch), tensile elongation (measured according to ASTM D-638,
The tensile speed was 5 mm / min), and the heat distortion temperature (measured according to ASTM D-648, load 18.6 kg / cm ² ) was measured. A 1 / 8-inch test piece for measuring heat distortion temperature was immersed in gasohol at 125 ° C (gasoline / methanol weight ratio 80/20) for 8 hours, and the change in weight was measured. Was evaluated. The results are shown in Table 1. As shown in Table 1, the composition of the present invention has the same heat distortion temperature and solvent resistance as those in which the olefin copolymer is not blended, and has extremely high tensile elongation and impact strength.

Comparative Examples 1 and 2 Instead of PPS-II or PPS-III, PPS-IV or PPS-V
The same operation as in Example 1 was performed, except that was used. The results are shown in Table 1.

Examples 3 to 5, Comparative Examples 3 to 5 PPS-III, an ethylene / glycidyl methacrylate copolymer, and glass fibers were kneaded with the composition shown in Table 1, and the same operation as in Example 1 was performed. The results are shown in Table 1.

[Effects of the Invention] As described above, the resin composition of the present invention comprises:
Polyphenylene sulfide is a polymer material that has excellent solvent resistance and heat resistance, and also has excellent mechanical strength, and is useful for applications such as automobiles, electricity and electronics.

Continuation of the front page (56) References JP-A-63-305131 (JP, A) JP-A-58-154757 (JP, A) JP-A-64-26671 (JP, A) JP-A-63-75059 (JP, A) , A) (58) Field surveyed (Int. Cl. ⁷ , DB name) C08L 81/00-81/02 C08L 23 / 02,23 / 04,23 / 08 C08L 33/14 C08G 75/02-75 / Ten

Claims (1)

(57) [Claims] (A) a melt viscosity of not less than 200 poise and a carboxyl group and / or a metal salt thereof of 0.1 to 5 mol%;
(Per phenyl sulfide unit) 60 to 99.5% by weight of polyphenylene sulfide, and (b) 40 to 0.5% by weight of an olefin copolymer composed of glycidyl ester of α-olefin / α, β-unsaturated acid. A polyphenylene sulfide resin composition characterized by the following: