JP5391509B2 - Polyamide resin composition - Google Patents

Description

  The present invention relates to a polyamide resin composition in which a polyphenylene sulfide resin is dispersed on the nanometer order in a resin composition comprising a polyamide resin, a polyolefin resin and a polyphenylene sulfide resin. More specifically, the present invention relates to a polyamide resin composition that is excellent in impact resistance at low temperatures, has significantly improved chemical resistance and barrier properties, and is excellent in moldability.

  Polyamide resins have excellent mechanical properties, toughness, thermal properties, and other properties that are suitable as engineering plastics. Therefore, various types of electrical / electronic parts, mechanical parts, automobile parts, etc. are mainly used for injection molding. Widely used in applications. In recent years, there has been an increase in resin molded products that require gas barrier properties for the purpose of preventing leakage of contents and mixing of outside air in order to ensure safety, storage stability, and prevention of environmental pollution. Of these, polyamide resins have been used as various molded articles because of their excellent gas barrier properties. However, the polyamide resin has a low barrier property against solvents having high polarity such as water and alcohol because it easily absorbs moisture, and its use range is often restricted, and improvement is desired. In addition, these materials that require barrier properties have applications that require toughness and impact resistance at low temperatures due to the variety of usage environments, and the demand is high.

  In order to compensate for the drawbacks of such polyamide resins, many resin compositions in which a polyphenylene sulfide resin (hereinafter abbreviated as PPS resin) excellent in water resistance and chemical resistance is combined with a polyamide resin have been proposed. For example, Patent Document 1 proposes a thermoplastic resin structure excellent in water resistance and chemical resistance in which a PPS resin is dispersed in a band in a polyamide resin. However, since the PPS resin having inferior toughness is dispersed in a band shape, the toughness, which is an advantage of the polyamide resin, is lowered, and a polyamide resin composition having improved toughness while having the toughness which is an advantage of the polyamide resin is further desired. It is rare.

Many resin compositions in which various polyolefin resins are blended with polyamide resins have been proposed in order to develop low temperature toughness of polyamide resins. For example, Patent Document 2 proposes a method of blending a modified polyolefin resin in a polyamide resin. However, although the impact resistance at low temperature is greatly improved, the barrier property is lowered, and the toughness and barrier property at low temperature are reduced. When both physical properties are required, it is not always sufficient.
JP 2001-302918 A (Claims) JP-A-11-335553 (Claims)

  The present invention seeks to solve the problems associated with the prior art as described above, and provides a polyamide resin composition having an excellent balance between barrier properties and low-temperature impact resistance and excellent moldability. This is the issue.

That is, the present invention
(1) (a) Polyamide resin 95-60% by weight, epoxy group, amino group, isocyanate group, hydroxyl group, mercapto group, ureido group, carboxylic acid group, carboxylic acid anhydride group, carboxylic acid ester group, and carboxylic acid metal (B) modified polyolefin resin 2 to 20% by weight, (c) unmodified polyolefin resin 2 to 20% by weight, (d) polyphenylene sulfide resin 1 to 1 containing at least one selected from bases in the polymer molecular chain A resin composition comprising 20% by weight, wherein (a) a polyamide resin is a continuous phase and (d) a polyphenylene sulfide resin is a dispersed phase in a resin phase separation structure observed with an electron microscope in the resin composition. (D) a polyamide characterized in that the polyphenylene sulfide resin is dispersed with a dispersed particle size of 1 to 300 nm Fat composition,
(2) The polyamide resin composition according to (1), wherein the modified polyolefin resin (b) is an ethylene / α-olefin copolymer modified with an unsaturated carboxylic acid or a derivative thereof,
(3) The (c) unmodified polyolefin resin is an ethylene / α-olefin copolymer obtained by copolymerizing ethylene and an α-olefin having 3 to 20 carbon atoms (1) Or (2) the polyamide resin composition according to any one of
(4) The polyamide resin composition according to any one of (1) to (3), which contains 0.01 to 10 parts by weight of a compatibilizing agent with respect to 100 parts by weight of the polyamide resin composition. ,
(5) The polyamide according to (4), wherein (e) the compatibilizer is at least one selected from the group consisting of a bisphenol-glycidyl ether epoxy compound, an organosilane compound having an epoxy group or an isocyanate group. Resin composition,
(6) Manufacture of a polyamide resin composition in which the material constituting the polyamide resin composition is supplied to a twin-screw extruder having a plasticizing part and a kneading part , and (a) kneaded at a processing temperature equal to or higher than the melting point of the polyamide resin. This is a method in which the kneading energy is 0.2 kW / (kg / h) or more, and the cylinder temperature of the plasticizing part is a resin having a higher melting point among (a) polyamide resin and (d) polyphenylene sulfide resin. The method for producing a polyamide resin composition according to any one of claims (1) to (5), wherein the melting point is in the range of the melting point to the melting point + 20 ° C, and the cylinder temperature of the kneading part is in the range of 100 to 250 ° C. ,
Is to provide.

  The polyamide resin composition of the present invention has an excellent balance between barrier properties and impact resistance at low temperatures, and also has excellent moldability. Therefore, it is used in applications where barrier properties for chemicals and gases are required in a low temperature environment. can do.

  Hereinafter, the present invention will be described in detail.

  The present invention relates to a polyamide resin composition in which a polyphenylene sulfide resin is dispersed on the nanometer order in a resin composition comprising a polyamide resin, a polyolefin resin and a polyphenylene sulfide resin. More specifically, the present invention relates to a polyamide resin composition that is excellent in impact resistance at low temperatures, has significantly improved chemical resistance and barrier properties, and is excellent in moldability.

  The (a) polyamide resin used in the present invention is a polyamide mainly composed of amino acids, lactams or diamines and dicarboxylic acids. Representative examples of the main constituents include amino acids such as 6-aminocaproic acid, 11-aminoundecanoic acid, 12-aminododecanoic acid and paraaminomethylbenzoic acid, lactams such as ε-caprolactam and ω-laurolactam, pentamethylenediamine , Hexamethylenediamine, 2-methylpentamethylenediamine, nonamethylenediamine, undecamethylenediamine, dodecamethylenediamine, 2,2,4- / 2,4,4-trimethylhexamethylenediamine, 5-methylnonamethylenediamine, Metaxylylenediamine, paraxylylenediamine, 1,3-bis (aminomethyl) cyclohexane, 1,4-bis (aminomethyl) cyclohexane, 1-amino-3-aminomethyl-3,5,5-trimethylcyclohexane, Bis (4-aminosi Chlohexyl) methane, bis (3-methyl-4-aminocyclohexyl) methane, 2,2-bis (4-aminocyclohexyl) propane, bis (aminopropyl) piperazine, aminoethylpiperazine, aliphatic, alicyclic, aromatic Diamines, and adipic acid, speric acid, azelaic acid, sebacic acid, dodecanedioic acid, terephthalic acid, isophthalic acid, 2-chloroterephthalic acid, 2-methylterephthalic acid, 5-methylisophthalic acid, 5-sodium sulfoisophthalic acid Examples include aliphatic, alicyclic, and aromatic dicarboxylic acids such as acids, 2,6-naphthalenedicarboxylic acid, hexahydroterephthalic acid, and hexahydroisophthalic acid. In the present invention, nylon derived from these raw materials Homopolymers or copolymers, each alone or in the form of a mixture It can be used.

  In the present invention, a particularly useful polyamide resin is a polyamide resin having a melting point of 150 ° C. or more and excellent in heat resistance and strength. Specific examples include polycaproamide (nylon 6), polyhexamethylene adipamide. (Nylon 66), polypentamethylene adipamide (nylon 56), polyhexamethylene sebamide (nylon 610), polyhexamethylene dodecane (nylon 612), polyundecanamide (nylon 11), polydodecanamide (nylon) 12), polycaproamide / polyhexamethylene adipamide copolymer (nylon 6/66), polycaproamide / polyhexamethylene terephthalamide copolymer (nylon 6 / 6T), polyhexamethylene adipamide / polyhexamethylene terephthalamide Copolymer (Nai 66 / 6T), polyhexamethylene adipamide / polyhexamethylene isophthalamide copolymer (nylon 66 / 6I), polyhexamethylene terephthalamide / polyhexamethylene isophthalamide copolymer (nylon 6T / 6I), polyhexamethylene terephthalamide / Polydodecanamide copolymer (nylon 6T / 12), polyhexamethylene adipamide / polyhexamethylene terephthalamide / polyhexamethylene isophthalamide copolymer (nylon 66 / 6T / 6I), polyxylylene adipamide (nylon XD6) Polyhexamethylene terephthalamide / poly-2-methylpentamethylene terephthalamide copolymer (nylon 6T / M5T), polynonamethylene terephthalamide (nylon 9T) and Mixtures of al and the like.

  Particularly preferred polyamide resins include nylon 6, nylon 66, nylon 12, nylon 610, nylon 6/66 copolymer, nylon 6T / 66 copolymer, nylon 6T / 6I copolymer, nylon 6T / 12, and nylon 6T / 6 copolymer. It is also practically suitable to use these polyamide resins as a mixture depending on necessary properties such as impact resistance and molding processability.

  The degree of polymerization of these polyamide resins is not particularly limited, but the relative viscosity measured at 25 ° C. in a 98% concentrated sulfuric acid solution having a sample concentration of 0.01 g / ml is in the range of 1.5 to 7.0. Particularly preferred is a polyamide resin in the range of 2.0 to 6.0.

  The content of the (a) polyamide resin used in the present invention is 95 to 60% by weight, preferably 90 to 70% by weight. If the content of the polyamide resin exceeds 95% by weight, it is not preferable because the low temperature toughness characteristic of the present invention becomes difficult to be expressed. Further, if the content of the polyamide resin is less than 60% by weight, it is not preferable because the barrier property is lowered.

  Moreover, a copper compound is preferably used in the polyamide resin of the present invention in order to improve long-term heat resistance. Specific examples of copper compounds include cuprous chloride, cupric chloride, cuprous bromide, cupric bromide, cuprous iodide, cupric iodide, cupric sulfate, nitric acid. Cupric, copper phosphate, cuprous acetate, cupric acetate, cupric salicylate, cupric stearate, cupric benzoate and inorganic copper halides and xylylenediamine, 2-mercaptobenzimidazole And complex compounds such as benzimidazole. Of these, monovalent copper compounds, particularly monovalent copper halide compounds are preferred, and cuprous acetate, cuprous iodide, and the like can be exemplified as particularly suitable copper compounds. The addition amount of the copper compound is usually preferably 0.01 to 2 parts by weight and more preferably 0.015 to 1 part by weight with respect to 100 parts by weight of the polyamide resin. If the amount added is too large, liberation of metallic copper occurs during melt molding, and the value of the product is reduced by coloring. In the present invention, an alkali halide can be added in combination with a copper compound. Examples of the alkali halide compound include lithium chloride, lithium bromide, lithium iodide, potassium chloride, potassium bromide, potassium iodide, sodium bromide and sodium iodide. Sodium chloride is particularly preferred.

  The (b) modified polyolefin resin used in the present invention is a polyolefin containing a functional group having an affinity for a polyamide resin in its molecule, particularly an epoxy group, amino group, isocyanate group, hydroxyl group, mercapto. A polyolefin containing at least one selected from a group, a ureido group, a carboxylic acid group, a carboxylic acid anhydride group, a carboxylic acid ester group and a carboxylic acid metal base in the polymer molecular chain, particularly preferably unsaturated An ethylene / α-olefin copolymer modified with a carboxylic acid or a derivative thereof.

  (B) The ethylene / α-olefin copolymer modified with an unsaturated carboxylic acid or a derivative thereof preferably used as a component of the modified polyolefin resin is at least one of ethylene and an α-olefin having 3 to 20 carbon atoms. The above-mentioned copolymer and modified resin, and specific examples of the α-olefin having 3 to 20 carbon atoms include propylene, 1-butene, 1-pentene, 1-hexene, 1-heptene, 1 -Octene, 1-nonene, 1-decene, 1-undecene, 1-dodecene, 1-tridecene, 1-tetradecene, 1-pentadecene, 1-hexadecene, 1-heptadecene, 1-octadecene, 1-nonadecene, 1-eicosene 3-methyl-1-butene, 3-methyl-1-pentene, 3-ethyl-1-pentene, 4-methyl-1-pentene, -Methyl-1-hexene, 4,4-dimethyl-1-hexene, 4,4-dimethyl-1-pentene, 4-ethyl-1-hexene, 3-ethyl-1-hexene, 9-methyl-1-decene , 11-methyl-1-dodecene, 12-ethyl-1-tetradecene, and combinations thereof. Among these α-olefins, a copolymer using an α-olefin having 3 to 12 carbon atoms is preferable from the viewpoint of improving mechanical strength. This ethylene / α-olefin copolymer preferably has an α-olefin content of 1 to 30 mol%, more preferably 2 to 25 mol%, and still more preferably 3 to 20 mol%. Further, non-conjugated dienes such as 1,4-hexadiene, dicyclopentadiene, 2,5-norbornadiene, 5-ethylidene norbornene, 5-ethyl-2,5-norbornadiene, 5- (1'-propenyl) -2-norbornene, etc. At least one kind may be copolymerized.

  Examples of the modifier used for acid modification include unsaturated carboxylic acids or derivatives thereof, such as acrylic acid, methacrylic acid, maleic acid, fumaric acid, itaconic acid, crotonic acid, methylmaleic acid, methylfumaric acid, citraconic acid, Glutaconic acid and metal salts of these carboxylic acids, methyl hydrogen maleate, methyl hydrogen itaconate, methyl acrylate, ethyl acrylate, butyl acrylate, 2-ethylhexyl acrylate, hydroxyethyl acrylate, methyl methacrylate, methacrylic acid 2 -Ethylhexyl, hydroxyethyl methacrylate, aminoethyl methacrylate, dimethyl maleate, dimethyl itaconate, maleic anhydride, itaconic anhydride, citraconic anhydride, endobicyclo- (2,2,1) -5-heptene-2, 3-dicarboxylic Endobicyclo- (2,2,1) -5-heptene-2,3-dicarboxylic anhydride, maleimide, N-ethylmaleimide, N-butylmaleimide, N-phenylmaleimide, glycidyl acrylate, glycidyl methacrylate, Glycidyl methacrylate, glycidyl itaconate, glycidyl citraconic acid, and 5-norbornene-2,3-dicarboxylic acid. Of these, unsaturated dicarboxylic acids and acid anhydrides thereof are preferred, and maleic acid and maleic anhydride are particularly preferred.

  The method for introducing these unsaturated carboxylic acid or its derivative component into the polyolefin resin is not particularly limited, and the olefin compound as the main component and the unsaturated carboxylic acid or its derivative compound may be copolymerized in advance, or may not be added to the unmodified polyolefin resin. A method such as introducing a saturated carboxylic acid or a derivative compound thereof by grafting using a radical initiator can be used. The amount of unsaturated carboxylic acid or its derivative component introduced is preferably within the range of 0.001 to 40 mol%, more preferably 0.01 to 35 mol%, based on the entire olefin monomer in the modified polyolefin. It is.

  The MFR (ASTM D 1238, 190 ° C., 2160 g load) of the modified polyolefin resin (b) of the present invention is preferably 0.01 to 70 g / 10 minutes, more preferably 0.03 to 60 g / 10 minutes. . When MFR is less than 0.01 g / 10 min, the fluidity is poor, and when it exceeds 70 g / 10 min, the impact strength may be lowered depending on the shape of the molded product, so care must be taken.

  The content of the (b) modified polyolefin resin used in the present invention is 2 to 20% by weight, preferably 5 to 15% by weight. If the content of the modified polyolefin resin exceeds 20% by weight, the barrier property is lowered, which is not preferable. On the other hand, when the content of the modified polyolefin resin is less than 2% by weight, it is not preferable because it is difficult to develop the high impact property that is a feature of the present invention.

The (c) unmodified polyolefin resin used in the present invention include polyethylene, polypropylene, polystyrene, Po Li 1-butene, poly-1-pentene, homopolymers such as polymethyl pentene, the unmodified ethylene · alpha-olefin A copolymer, a vinyl alcohol ester homopolymer, a polymer obtained by hydrolyzing at least a part of a vinyl alcohol ester homopolymer, [a copolymer of (ethylene and / or propylene) and vinyl alcohol ester] polymer] obtained by partially hydrolyzing, block copolymers of Conjugate diene and a vinyl aromatic hydrocarbon, and, hydrides of the block copolymer.

Of these, unmodified ethylene · alpha-olefin copolymer has preferably.

  The preferred ethylene / α-olefin copolymer used as a component of the (c) unmodified polyolefin resin used in the present invention is an ethylene / α-olefin copolymer comprising ethylene and an α-olefin having 3 to 20 carbon atoms. The coalescence is a copolymer comprising ethylene and at least one α-olefin having 3 to 20 carbon atoms as constituent components. Specific examples of the α-olefin having 3 to 20 carbon atoms include propylene, 1-butene, 1-pentene, 1-hexene, 1-heptene, 1-octene, 1-nonene, 1-decene and 1-undecene. 1-dodecene, 1-tridecene, 1-tetradecene, 1-pentadecene, 1-hexadecene, 1-heptadecene, 1-octadecene, 1-nonadecene, 1-eicosene, 3-methyl-1-butene, 3-methyl-1 -Pentene, 3-ethyl-1-pentene, 4-methyl-1-pentene, 4-methyl-1-hexene, 4,4-dimethyl-1-hexene, 4,4-dimethyl-1-pentene, 4-ethyl -1-hexene, 3-ethyl-1-hexene, 9-methyl-1-decene, 11-methyl-1-dodecene, 12-ethyl-1-tetradecene and these See fit, and the like. Among these α-olefins, a copolymer using an α-olefin having 6 to 12 carbon atoms is more preferable because mechanical strength is improved and a reforming effect is further improved.

  The melt flow rate (hereinafter abbreviated as MFR) of the (c) unmodified polyolefin resin of the present invention is preferably 0.01 to 70 g / 10 minutes, more preferably 0, according to ASTM D 1238, 190 ° C., 2160 g load. 0.03 to 60 g / 10 min. When MFR is less than 0.01 g / 10 min, the fluidity is poor, and when it exceeds 70 g / 10 min, the impact strength may be lowered depending on the shape of the molded product, so care must be taken.

  The content of (c) unmodified polyolefin resin used in the present invention is 2 to 20% by weight, preferably 5 to 15% by weight. If the content of the unmodified polyolefin resin exceeds 20% by weight, the barrier property is lowered, which is not preferable. Further, if the content of the unmodified polyolefin resin is less than 2% by weight, it is not preferable because it is difficult to develop the high impact property that is a feature of the present invention.

  As the (d) PPS resin used in the present invention, a polymer having a repeating unit represented by the following structural formula can be used.

  From the viewpoint of heat resistance, a polymer containing 70 mol% or more, more preferably 90 mol% or more of the repeating unit represented by the structural formula is preferable. Moreover, about 30 mol% or less of the repeating units of the PPS resin may be composed of repeating units having any of the following structures. Of these, a p-phenylene sulfide / m-phenylene sulfide copolymer (m-phenylene sulfide unit 20% or less) is preferably used because it has both moldability and barrier properties.

  Such a PPS resin can be produced in a high yield by recovering and post-treating a PPS resin obtained by reacting a polyhalogen aromatic compound and a sulfidizing agent in a polar organic solvent. Specifically, a method for obtaining a polymer having a relatively small molecular weight described in JP-B-45-3368, or a relatively molecular weight described in JP-B-52-12240 and JP-A-61-7332 is disclosed. It can also be produced by a method for obtaining a large polymer. Crosslinking / high molecular weight of the PPS resin obtained as described above by heating in air, heat treatment under an inert gas atmosphere such as nitrogen or under reduced pressure, washing with organic solvent, hot water, acid aqueous solution, etc., acid anhydride It can also be used after being subjected to various treatments such as activation with functional group-containing compounds such as amines, isocyanates, and functional group-containing disulfide compounds.

  As a specific method for crosslinking / high molecular weight of PPS resin by heating, under an oxidizing gas atmosphere such as air or oxygen or a mixed gas atmosphere of the oxidizing gas and an inert gas such as nitrogen or argon. Examples of the method include heating in a heating container at a predetermined temperature until a desired melt viscosity is obtained. The heat treatment temperature is usually 170 to 280 ° C, preferably 200 to 270 ° C. The heat treatment time is usually selected from 0.5 to 100 hours, preferably from 2 to 50 hours. By controlling both of these, the target viscosity level can be obtained. The heat treatment apparatus may be a normal hot air drier, or a heating apparatus with a rotary type or a stirring blade, but for efficient and more uniform processing, a heating type with a rotary type or a stirring blade is used. It is preferable to use an apparatus.

  As a specific method for heat-treating the PPS resin under an inert gas atmosphere such as nitrogen or under reduced pressure, a heat treatment temperature of 150 to 280 ° C., preferably 200 to 200 ° C. under an inert gas atmosphere such as nitrogen or under reduced pressure. A method of heat treatment at 270 ° C. and a heating time of 0.5 to 100 hours, preferably 2 to 50 hours can be exemplified. The heat treatment apparatus may be a normal hot air drier, or a heating apparatus with a rotary type or a stirring blade, but for efficient and more uniform processing, a heating type with a rotary type or a stirring blade is used. More preferably, an apparatus is used.

  The (d) PPS resin used in the present invention is preferably a PPS resin that has been subjected to a cleaning treatment. Specific examples of the cleaning treatment include acid aqueous solution washing treatment, hot water washing treatment, and organic solvent washing treatment. These treatments may be used in combination of two or more methods.

  The following method can be illustrated as a specific method when the PPS resin is washed with an organic solvent. That is, the organic solvent used for washing is not particularly limited as long as it does not have an action of decomposing the PPS resin. For example, nitrogen-containing polar solvents such as N-methylpyrrolidone, dimethylformamide, and dimethylacetamide, dimethyl sulfoxide Sulfoxides such as dimethylsulfone, sulfone solvents, ketone solvents such as acetone, methyl ethyl ketone, diethyl ketone, acetophenone, ether solvents such as dimethyl ether, dipropyl ether, tetrahydrofuran, chloroform, methylene chloride, trichloroethylene, ethylene chloride, dichloroethane , Halogen solvents such as tetrachloroethane, chlorobenzene, methanol, ethanol, propanol, butanol, pentanol, ethylene glycol, propylene glycol Lumpur, phenol, cresol, alcohols such as polyethylene glycol, phenolic solvents, benzene, toluene, and aromatic hydrocarbon solvents such as xylene. Among these organic solvents, use of N-methylpyrrolidone, acetone, dimethylformamide, chloroform or the like is preferable. These organic solvents are used alone or in combination of two or more.

  As a method of washing with an organic solvent, there is a method of immersing a PPS resin in an organic solvent, and if necessary, stirring or heating can be appropriately performed. There is no restriction | limiting in particular about the washing | cleaning temperature at the time of wash | cleaning PPS resin with an organic solvent, Arbitrary temperature of about normal temperature-about 300 degreeC can be selected. Although the cleaning efficiency tends to increase as the cleaning temperature increases, a sufficient effect is usually obtained at a cleaning temperature of room temperature to 150 ° C. The PPS resin that has been washed with an organic solvent is preferably washed several times with water or warm water in order to remove the remaining organic solvent.

  The following method can be illustrated as a specific method when the PPS resin is washed with hot water. That is, it is preferable that the water used is distilled water or deionized water in order to express the preferable chemical modification effect of the PPS resin by hot water washing. The operation of the hot water treatment is usually performed by charging a predetermined amount of PPS resin into a predetermined amount of water, and heating and stirring at normal pressure or in a pressure vessel. The ratio of the PPS resin to water is preferably larger, but usually a bath ratio of 200 g or less of PPS resin is selected for 1 liter of water.

  Further, when washing with hot water, it is preferable to use an aqueous solution containing a Group II metal element of the periodic table. The aqueous solution containing a Group II metal element of the periodic table is obtained by adding a water-soluble salt containing a Group II metal element of the periodic table to the water. The concentration of the water-soluble salt having a Group II metal element in the periodic table with respect to water is preferably in the range of about 0.001 to 5% by weight.

Among the Group II metal elements of the periodic table used here, preferred metal elements include Ca, Mg, Ba and Zn, and the counter anions include acetate ions, halide ions, hydroxide ions. And carbonate ions. More specific and preferred compounds include Ca acetate, Mg acetate, Zn acetate, CaCl ₂ , CaBr ₂ , ZnCl ₂ , CaCO ₃ , Ca (OH) ₂ and CaO, and particularly preferably Ca acetate. is there.

  The temperature of the aqueous solution containing a Group II metal element in the periodic table is preferably 130 ° C. or higher, more preferably 150 ° C. or higher. Although there is no restriction | limiting in particular about the upper limit of washing | cleaning temperature, When using a normal autoclave, about 250 degreeC is a limit.

  The bath ratio of the aqueous solution containing the Group II metal element in the periodic table is preferably selected in the range of 2 to 100, more preferably 4 to 50, and 5 to 15 with respect to the dry polymer 1 by weight. More preferably, it is in the range.

  The following method can be illustrated as a specific method when the PPS resin is washed with an acid aqueous solution. That is, there is a method of immersing a PPS resin in an acid or an aqueous solution of an acid, and stirring or heating can be performed as necessary. The acid used is not particularly limited as long as it does not have an action of decomposing PPS resin, and is saturated with aliphatic monocarboxylic acid such as formic acid, acetic acid, propionic acid and butyric acid, and halo-substituted aliphatic such as chloroacetic acid and dichloroacetic acid. Aliphatic unsaturated monocarboxylic acids such as saturated carboxylic acid, acrylic acid and crotonic acid, aromatic carboxylic acids such as benzoic acid and salicylic acid, dicarboxylic acids such as oxalic acid, malonic acid, succinic acid, phthalic acid and fumaric acid, sulfuric acid Inorganic acid compounds such as phosphoric acid, hydrochloric acid, carbonic acid and silicic acid. Of these, acetic acid and hydrochloric acid are more preferably used. It is preferable to wash the acid-treated PPS resin several times with water or warm water in order to remove the remaining acid or salt. The water used for washing is preferably distilled water or deionized water in the sense that the effect of the preferred chemical modification of the PPS resin by acid treatment is not impaired.

  The melt viscosity of the (d) PPS resin used in the present invention is not particularly limited as long as melt kneading is possible, but usually the melt flow rate (MFR) is 10 to 10,000 g / 10 min (315.5 ° C., 5 kg). Load) is preferably used, and a range of 50 to 1000 g / 10 min is more preferable.

  The content of (d) PPS resin used in the present invention is 1 to 20% by weight, preferably 2 to 10 parts by weight. If the PPS resin is less than 1% by weight, it is difficult to obtain an effect of improving the barrier property. Conversely, if the PPS resin is more than 20% by weight, the impact resistance is significantly lowered, which is not preferable.

  In the polyamide resin composition of the present invention, (a) the polyamide resin forms a continuous phase, (d) the PPS resin forms a dispersed phase, and (d) the PPS resin is dispersed with a dispersed particle size in the range of 1 to 300 nm. There is a need. The dispersed particle size referred to here is a thin piece of 80 nm thickness cut from the center of ASTM No. 1 dumbbell piece created by injection molding in the cross-sectional area direction of the dumbbell piece and observed with a transmission electron microscope (magnification: 10,000 times). For any 100 dispersed particles, the maximum and minimum diameters are first measured to determine the average value, and then the average value of the 100 average values is measured as the number average particle diameter. . A particularly preferable range of the dispersed particle diameter is 10 to 200 nm. (D) When the dispersed particle size of the PPS resin is outside the range of 1 to 300 nm, the polyamide having excellent mechanical properties and low-temperature toughness, which are the problems of the present invention, and having greatly improved chemical resistance and barrier properties A resin composition cannot be obtained.

  In the polyamide resin composition of the present invention, (a) the polyamide resin forms a continuous phase, (b) the modified polyolefin resin and (c) the unmodified polyolefin resin forms a dispersed phase, and (b) the modified polyolefin resin and (c ) The unmodified polyolefin resin is preferably dispersed with a dispersed particle size in the range of 1 to 2000 nm, more preferably 30 to 1000 nm. When the dispersed particle size of (b) modified polyolefin resin and (c) unmodified polyolefin resin is outside the range of 1 to 2000 nm, the balance between low temperature toughness and barrier property may be reduced.

  When the polyamide resin composition of the present invention is (a) the polyamide resin forms a continuous phase, (d) the PPS resin forms a dispersed phase, and (d) the PPS resin is dispersed with a dispersed particle size in the range of 1 to 300 nm. The thickness of the interface phase in which both components coexist at the boundary between the two resins is preferably 20 to 70 nm, more preferably 30 to 60 nm. The thickness of the interfacial phase referred to here is a thin piece having a thickness of 80 nm cut from the center of the injection-molded piece in the direction of the cross-sectional area of the dumbbell piece, and an arbitrary 10 dispersed particles are attached with a field emission electron microscope. Obtained by EDX-ray analysis (energy dispersive X-ray spectroscopic analysis) on the line crossing the line and measuring the length of the region where the oxygen atom concentration of the polyamide resin and the sulfur atom concentration of the PPS resin continuously change The average value of When the thickness of the interface phase is less than 20 nm, the barrier property may be deteriorated. On the other hand, when the thickness of the interfacial phase exceeds 70 nm, the fluidity may be lowered and the processability may be deteriorated. Further, in order to control the thickness of the interfacial phase as described above, it is important to appropriately select (e) a compatibilizing agent, and the compatibilizing agent reacts with the PPS resin and the polyamide resin to cause graft type or star type. It is preferable that the compatibilizing component is formed.

  In order to improve the compatibility of (a) the polyamide resin and (d) the PPS resin, it is preferable to add (e) a compatibilizing agent to the polyamide resin composition of the present invention. (E) By adding a compatibilizing agent, (d) by improving the compatibility of the PPS resin, the dispersed particle size of the PPS resin can be made fine and the interfacial phase can be made thick. The balance can be improved. (E) Specific examples of the compatibilizer include organic silanes such as alkoxysilanes having at least one functional group selected from an epoxy group, amino group, isocyanate group, hydroxyl group, mercapto group, and ureido group. A compound, a polyfunctional epoxy compound, etc. are mentioned, These can also be used simultaneously 2 or more types. Here, the polyfunctional epoxy compound contains two or more epoxy groups in the molecule, and a liquid or solid one can be used. For example, a copolymer of an α-olefin such as ethylene, propylene, 1-butene and an α, β-unsaturated glycidyl ester such as glycidyl acrylate, glycidyl methacrylate, glycidyl ethacrylate, bisphenol A, resorcinol, hydroquinone, Pyrocatechol, bisphenol F, saligenin, 1,3,5-trihydroxybenzene, bisphenol S, trihydroxy-diphenyldimethylmethane, 4,4′-dihydroxybiphenyl, 1,5-dihydroxynaphthalene, cashew phenol, 2,2, Bisphenol-glycidyl ether type epoxy compounds such as 5,5-tetrakis (4-hydroxyphenyl) hexane, glycidyl ester type epoxy compounds such as glycidyl phthalate, N-glycidyl aniline, etc. Glycidyl amine-based epoxy compounds, novolak type novolak epoxy resins phenol resin is reacted with epichlorohydrin is exemplified. Preferably, a bisphenol-glycidyl ether type epoxy compound having high reactivity with both a polyamide resin and a PPS resin, an organic silane compound having an epoxy group or an isocyanate group is used. In particular, when an organosilane compound having an isocyanate group is used, the interfacial phase thickness can be increased, which is particularly preferable.

  (E) The compounding ratio of the compatibilizing agent is preferably 0.01 to 10 parts by weight, more preferably 0.1 to 5 parts by weight with respect to 100 parts by weight of the polyamide resin composition. When the addition amount is 0.01 parts by weight or less, a sufficient compatibility improving effect cannot be obtained, and when it exceeds 10 parts by weight, the melt viscosity of the polyamide resin composition may remarkably increase and the fluidity may decrease.

  Furthermore, in the present invention, in order to maintain high heat resistance and thermal stability, it is preferable to include one or more (f) antioxidants selected from phenolic and phosphorus compounds. The blending amount of the antioxidant is preferably 0.01 parts by weight or more, particularly 0.02 parts by weight or more with respect to 100 parts by weight of the polyamide resin composition from the viewpoint of heat resistance improvement effect, and is generated during molding. From the viewpoint of the gas component, it is preferably 5 parts by weight or less, particularly preferably 1 part by weight or less. In addition, the combined use of phenolic and phosphorus antioxidants is particularly preferable because of their large heat resistance, thermal stability and fluidity retention effect.

  As the phenolic antioxidant, a hindered phenolic compound is preferably used. Specific examples include triethylene glycol-bis [3-t-butyl- (5-methyl-4-hydroxyphenyl) propionate], N, N′-hexamethylenebis (3,5-di-t-butyl-4-hydroxy-hydrocinnamamide), tetrakis [methylene-3- (3 ′, 5′-di-t-butyl-4′-hydroxy) Phenyl) propionate] methane, pentaerythrityltetrakis [3- (3 ′, 5′-di-t-butyl-4′-hydroxyphenyl) propionate], 1,3,5-tris (3,5-di-t -Butyl-4-hydroxybenzyl) -s-triazine-2,4,6- (1H, 3H, 5H) -trione, 1,1,3-tris (2-methyl- -Hydroxy-5-t-butylphenyl) butane, 4,4'-butylidenebis (3-methyl-6-t-butylphenol), n-octadecyl-3- (3,5-di-t-butyl-4-hydroxy -Phenyl) propionate, 3,9-bis [2- (3- (3-t-butyl-4-hydroxy-5-methylphenyl) propionyloxy) -1,1-dimethylethyl] -2,4,8, Examples include 10-tetraoxaspiro [5,5] undecane, 1,3,5-trimethyl-2,4,6-tris- (3,5-di-t-butyl-4-hydroxybenzyl) benzene.

  Among them, ester type polymer hindered phenol type is preferable. Specifically, tetrakis [methylene-3- (3 ′, 5′-di-t-butyl-4′-hydroxyphenyl) propionate] methane, pentaerythrityl. Tetrakis [3- (3 ′, 5′-di-t-butyl-4′-hydroxyphenyl) propionate], 3,9-bis [2- (3- (3-t-butyl-4-hydroxy-5- Methylphenyl) propionyloxy) -1,1-dimethylethyl] -2,4,8,10-tetraoxaspiro [5,5] undecane and the like are preferably used.

  Next, phosphorus antioxidants include bis (2,6-di-t-butyl-4-methylphenyl) pentaerythritol-di-phosphite, bis (2,4-di-t-butylphenyl). ) Pentaerythritol di-phosphite, bis (2,4-di-cumylphenyl) pentaerythritol di-phosphite, tris (2,4-di-t-butylphenyl) phosphite, tetrakis (2,4-di-t-butylphenyl) -4,4'-bisphenylene phosphite, di-stearyl pentaerythritol di-phosphite, triphenyl phosphite, 3,5-dibutyl-4-hydroxybenzyl phosphite Examples include phonate diethyl ester. Among them, those having a high melting point of the antioxidant are preferably used in order to reduce volatilization and decomposition of the antioxidant in the compound.

  Furthermore, a resin other than the PPS resin can be added to the polyamide resin composition of the present invention as long as the effects of the present invention are not impaired. However, if it exceeds 30 parts by weight relative to 100 parts by weight of the entire polyamide resin composition of the present invention, the original characteristics of the polyamide resin are impaired, and in particular, addition of 20 parts by weight or less is preferably used.

  Specific examples of the resin include polyester resin, polyolefin resin, modified polyphenylene ether resin, polysulfone resin, polyketone resin, polyetherimide resin, polyarylate resin, polyethersulfone resin, polyether ketone resin, polythioether ketone resin, poly Examples include ether ether ketone resins, polyimide resins, polyamideimide resins, and tetrafluoropolyethylene resins. Moreover, the following compounds can be added for the purpose of modification. Coupling agents such as isocyanate compounds, organosilane compounds, organotitanate compounds, organoborane compounds, epoxy compounds, polyalkylene oxide oligomer compounds, thioether compounds, ester compounds, organophosphorus compounds, etc. , Talc, kaolin, organic phosphorus compound, crystal nucleating agent such as polyether ether ketone, montanic acid wax, metal soap such as lithium stearate, aluminum stearate, ethylenediamine / stearic acid / sebacic acid heavy compound, silicone Conventional additives such as release agents such as compounds, anti-coloring agents such as hypophosphite, and other lubricants, UV inhibitors, colorants, flame retardants, and foaming agents can be blended. If any of the above compounds exceeds 20 parts by weight relative to 100 parts by weight of the entire polyamide resin composition of the present invention, the original properties of the polyamide resin may be impaired, and it is preferably 10 parts by weight or less, more preferably 1 part by weight or less. Addition is good.

  The polyamide resin composition obtained by the method of the present invention can be used by blending a filler as long as the effects of the present invention are not impaired. Specific examples of such fillers include glass fiber, carbon fiber, potassium titanate whisker, zinc oxide whisker, calcium carbonate whisker, wollastonite whisker, aluminum borate whisker, aramid fiber, alumina fiber, silicon carbide fiber, ceramic fiber, asbestos fiber, Fibrous fillers such as stone kou fiber, metal fibers, or silicates such as talc, wollastonite, zeolite, sericite, mica, kaolin, clay, pyrophyllite, bentonite, asbestos, alumina silicate, silicon oxide, magnesium oxide , Metal compounds such as alumina, zirconium oxide, titanium oxide and iron oxide, carbonates such as calcium carbonate, magnesium carbonate and dolomite, sulfates such as calcium sulfate and barium sulfate, calcium hydroxide, magnesium hydroxide and hydroxide Non-fibrous fillers such as hydroxides such as luminium, glass beads, glass flakes, glass powders, ceramic beads, boron nitride, silicon carbide, carbon black and silica, graphite are used, and these may be hollow Further, two or more kinds of these fillers can be used in combination. These fillers may be used after pretreatment with a coupling agent such as an isocyanate compound, an organic silane compound, an organic titanate compound, an organic borane compound, and an epoxy compound.

  As a method for producing the polyamide resin composition of the present invention, the material is supplied to a generally known melt kneader such as a single-screw or twin-screw extruder, a Banbury mixer, a kneader, and a mixing roll to process the melting point of the polyamide resin or higher. A typical example is a method of kneading at a temperature. In order to control the morphology of the present invention and the particle size of the dispersed PPS resin as described above, kneading energy during extrusion (extruder per discharge amount) It is preferable to increase the work amount (kW / (kg / h)). As a result, the PPS resin can be finely dispersed in the polyamide resin. The kneading energy is preferably 0.2 or more, particularly preferably 0.25 or more. However, if the kneading energy is usually increased, the resin temperature rises due to heat generated by shearing, causing thermal decomposition of the polyamide resin, making it difficult to form the desired phase separation structure. Therefore, the resin temperature during extrusion is preferably 260 ° C to 320 ° C. By controlling the kneading energy and the resin temperature in this way, it is possible to form a target resin phase separation structure. Specifically, when a twin-screw extruder is used, the cylinder configuration of the twin-screw extruder is usually divided into a plasticizing section that plasticizes the charged resin and a kneading section that melts and kneads the plasticized molten resin. However, regarding the cylinder temperature when melt-kneading using a twin-screw extruder, the plasticizing part is set to a temperature between the melting point of the higher melting point resin of the polyamide resin and the PPS resin to the melting point + 20 ° C. In order to suppress the heat generation at the cylinder temperature of the kneading part, the above conditions can be achieved by setting the temperature within the range of 100 to 250 ° C. At this time, the mixing order of the raw materials is not particularly limited, and a method in which all raw materials are blended and then melt-kneaded by the above method, a part of the raw materials are blended and then melt-kneaded by the above method, and the remaining raw materials are blended. Any method such as a method of melt kneading or a method of mixing a part of raw materials and mixing the remaining raw materials using a side feeder during melt kneading by a single-screw or biaxial extruder may be used. In addition, as for the small amount additive component, other components may be kneaded and pelletized by the above-described method or the like, and then added before molding and used for molding.

  Since the polyamide resin composition of the present invention is excellent in balance between low-temperature toughness and barrier property, it is particularly useful for applications that require chemical and gas barrier properties in a low-temperature environment. In addition, taking advantage of its characteristics, it is particularly suitable for use in general equipment, automotive parts, electrical and electronic parts and the like.

  The present invention will be described more specifically with reference to the following examples. The material properties were evaluated according to the following method.

  [Fuel Permeability Coefficient] A disk-shaped test piece (diameter 6 cm) having a thickness of 1 mm was prepared by injection molding (SG75H-MIV manufactured by Sumitomo Heavy Industries, Ltd., cylinder temperature 280 ° C., mold temperature 80 ° C.). The obtained test piece was attached to GTR-30XATK (manufactured by GTR Tech), and model gasoline (a mixture of (i) toluene and isooctane in a 50/50 volume ratio and (b) ethanol in 90 pairs) was placed in the upper cell of the test piece. (Alcohol gasoline mixture mixed at 10 volume ratio) was charged and measured at a measurement temperature of 60 ° C. according to JIS K7126 A method (differential pressure method).

  [Izod Impact Strength] Izod impact strength with a notch was measured according to ASTM-D256.

  [−20 ° C. Izod Impact Strength] Notched Izod impact strength was measured according to ASTM-D256 except that the temperature atmosphere was −20 ° C.

  [Minimum molding pressure] The minimum molding pressure that can be molded without causing filling failure by ASTM No. 1 dumbbell by injection molding (SG75H-MIV, Sumitomo Heavy Industries, Ltd., cylinder temperature 280 ° C, mold temperature 80 ° C) It was. The lower the molding lower limit pressure, the better the fluidity.

  [Dispersion Particle Size] Obtained by cutting a thin 80 nm-thick piece from the center of ASTM No. 1 dumbbell piece prepared in the above method in the direction of the cross-sectional area of the dumbbell piece and observing it with a transmission electron microscope at a magnification of 10,000 times. Using the image processing software “Scion Image” (manufactured by Scion Corporation) for the dispersed part of 100 arbitrary PPS resin dispersed particles, the average value is obtained by measuring the maximum diameter and the minimum diameter of each particle. Thereafter, the number average value of the 100 average values was obtained.

  [Interfacial Phase Thickness] The interfacial phase thickness of the dispersed PPS resin was measured as follows. A thin piece having a thickness of 80 nm is cut in the direction of the cross-sectional area of the dumbbell piece from the center of the ASTM No. 1 dumbbell piece produced by the above method, and about 10 dispersed particles with a field emission electron microscope, as shown in FIG. EDX ray analysis (energy dispersive X-ray spectroscopic analysis) of the atomic concentration on the line across the surface, and the length of the region where the oxygen atom concentration of the polyamide resin and the sulfur atom concentration of the PPS resin continuously change are measured and averaged The value was determined.

[Example 1], [Comparative Examples 1 to 5]
Each component shown below was dry-blended in the proportions shown in Table 1, and then the cylinder temperature and screw rotation speed were set in Table 1 using a TEX30 twin screw extruder (L / D: 45.5) manufactured by Nippon Steel Works. The mixture was melt-kneaded under the conditions shown in Fig. 1 and pelletized with a strand cutter. Thereafter, test pieces were prepared by injection molding (SG75H-MIV, Sumitomo Heavy Industries, Ltd., cylinder temperature: 280 ° C., mold temperature: 80 ° C.) using pellets that were vacuum-dried overnight at 80 ° C. Table 1 shows the results of evaluating the morphology, impact resistance, and barrier properties of each sample. In this example, compared with Comparative Examples 1 to 5, the impact resistance and the barrier property were balanced.

[Examples 2 to 7]
Evaluation was performed in the same manner as in Example 1 except that a dry blend of a PPS resin and a compatibilizing agent was added from a supply port provided in the middle of the TEX30 twin-screw extruder (L / D: around 20). In this example, compared with Comparative Examples 1 to 5, the impact resistance and the barrier property were balanced.

The (a) polyamide resin used in the examples and comparative examples is as follows.
(A-1): Nylon 66 resin (“Amilan” CM3001-N manufactured by Toray) having a melting point of 262 ° C.
(A-2): Nylon 66 resin having a melting point of 262 ° C. (“Amilan” CM3006 manufactured by Toray, with heat-resistant agent).
(A-3): Nylon 6 resin having a melting point of 225 ° C. (“Amilan” CM1010 manufactured by Toray).

Similarly, (b) the modified polyolefin resin is as follows.
(B-1): Acid-modified ethylene / 1-butene copolymer (“Tafmer” MH7020 manufactured by Mitsui Chemicals).
(B-2): Ethylene / glycidyl methacrylate copolymer (“Bondfast” ETX6, manufactured by Sumitomo Chemical).

Similarly, (c) unmodified polyolefin resin is as follows.
(C-1): Ethylene / 1-butene copolymer (“Tuffmer” TX-610 manufactured by Mitsui Chemicals).
(C-2): Linear low density polyethylene (LLDPE: “Evolue” SP0540 manufactured by Mitsui Chemicals).

Similarly, (d) PPS resin is as follows.
(D-1): PPS resin (M2088 manufactured by Toray) having a melting point of 280 ° C. and MFR = 100 g / 10 minutes (315.5 ° C., 5 kg load).
(D-2): PPS resin (M2888 manufactured by Toray) having a melting point of 280 ° C. and MFR = 600 g / 10 minutes (315.5 ° C., 5 kg load).
(D-3): PPS resin (M3910 manufactured by Toray) having a melting point of 280 ° C. and MFR = 2000 g / 10 minutes (315.5 ° C., 5 kg load).

Similarly, (e) the compatibilizer is as follows.
(E-1): γ-glycidoxypropyltrimethoxysilane (SH6040 manufactured by Toray Dow Corning Silicone).
(E-2): 3-isocyanatopropyltriethoxysilane (KBE-9007 manufactured by Shin-Etsu Silicone).

Similarly, the following compounds were used as (f) antioxidants.
(F-1): Pentaerythrityltetrakis [3- (3 ′, 5′-di-t-butyl-4′-hydroxyphenyl) propionate] (TTHP manufactured by Toray Fine Chemicals).
(F-2): N, N′-hexamethylenebis (3,5-di-t-butyl-4-hydroxy-hydrocinnamamide) (TTAD manufactured by Toray Fine Chemical).
(F-3): Bis (2,6-di-t-butyl-4-methylphenyl) pentaerythritol di-phosphite (Adeka Stub PEP-36 manufactured by Asahi Denka).

It is a model figure which shows an example of a field emission type electron microscope-EDX ray analysis when measuring the interface phase thickness of the PPS resin or the polyamide resin dispersed in the polyamide resin continuous phase.

Claims (6)

(A) Among polyamide resin 95-60% by weight, epoxy group, amino group, isocyanate group, hydroxyl group, mercapto group, ureido group, carboxylic acid group, carboxylic acid anhydride group, carboxylic acid ester group, and carboxylic acid metal base (B) 2 to 20% by weight of a modified polyolefin resin, (c) 2 to 20% by weight of an unmodified polyolefin resin, and (d) 1 to 20% by weight of a polyphenylene sulfide resin. A resin phase separation structure observed with an electron microscope in the resin composition, wherein (a) a polyamide resin forms a continuous phase, (d) a polyphenylene sulfide resin forms a dispersed phase, (D) A polyamide resin set in which the polyphenylene sulfide resin is dispersed with a dispersed particle size of 1 to 300 nm. Thing. The polyamide resin composition according to claim 1, wherein the (b) modified polyolefin resin is an ethylene / α-olefin copolymer modified with an unsaturated carboxylic acid or a derivative thereof. 3. The ethylene / α-olefin copolymer obtained by copolymerizing the (c) unmodified polyolefin resin with ethylene and an α-olefin having 3 to 20 carbon atoms. A polyamide resin composition as described above. The polyamide resin composition according to any one of claims 1 to 3, wherein 0.01 to 10 parts by weight of (e) a compatibilizing agent is contained with respect to 100 parts by weight of the polyamide resin composition. 5. The polyamide resin composition according to claim 4, wherein (e) the compatibilizing agent is at least one selected from the group consisting of a bisphenol-glycidyl ether epoxy compound, an organosilane compound having an epoxy group or an isocyanate group. . A method for producing a polyamide resin composition in which the material constituting the polyamide resin composition is supplied to a twin-screw extruder having a plasticizing part and a kneading part , and (a) the material is kneaded at a processing temperature equal to or higher than the melting point of the polyamide resin. The kneading energy is 0.2 kW / (kg / h) or more, and the cylinder temperature of the plasticized part is the melting point of the higher melting point of (a) polyamide resin and (d) polyphenylene sulfide resin. The method for producing a polyamide resin composition according to any one of claims 1 to 5, wherein the melting point is in the range of + 20 ° C, and the cylinder temperature of the kneading part is in the range of 100 to 250 ° C.

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