JP2018193437A - Thermoplastic resin composition and molded article obtained by molding the same - Google Patents

Abstract

To provide a thermoplastic resin composition which contains a semi-aromatic polyamide and a flame retardant, suppresses deterioration in heat resistance and chemical resistance, and is improved in fluidity.SOLUTION: The thermoplastic resin composition contains: 100 pts.mass in total of a semi-aromatic polyamide (A) and an aliphatic polyamide (B); 20-100 pts.mass of a bromine-based flame retardant (C); and 2-25 pts.mass of an antimony-based flame retardant aid (D). The mass ratio (A/B) is 90/10-40/60. The semi-aromatic polyamide (A) has a melting point of 280°C or higher. The mass increase rate R after 48-hour immersion in 50% sulfuric acid at 23°C is 50% or less.SELECTED DRAWING: None

Description

  The present invention relates to a thermoplastic resin composition, and more particularly, to a resin composition containing a semi-aromatic polyamide and a molded body formed by molding the resin composition.

  Polyamide is excellent in heat resistance, mechanical properties, and molding processability, so it is used as many electrical / electronic parts and parts around automobile engines.

In recent years, the method of mounting electrical and electronic parts such as connectors on electronic boards has been a surface mounting method by reflow using lead-free solder from the environmental aspect. Therefore, the molded body constituting the electric / electronic component is required to have heat resistance enough to withstand heating in the reflow furnace.
For example, since aliphatic polyamides such as polyamide 6 and polyamide 66 have a low melting point, there is a problem that a molded body made of these resins melts and deforms due to reflow. The polyamide 46 has a high melting point but is easy to absorb water. The molded body made of the polyamide 46 has a blister phenomenon in which moisture is foamed during the reflow process and the surface of the molded body swells. The body needed to be stored in a low humidity environment. For this reason, in recent years, semi-aromatic polyamides having a high melting point and a low water absorption rate are often used for molded products for surface-mounted electrical / electronic components.

  In addition, since electrical and electronic parts are required to have flame retardancy, as a composition in which a flame retardant is blended with polyamide, for example, Patent Document 1 discloses a semi-aromatic polyamide or a copolymer semi-aromatic polyamide. A resin composition containing a brominated flame retardant is disclosed. However, the semi-aromatic polyamide has a melting point close to the decomposition temperature compared to the aliphatic polyamide, and the molding process temperature cannot be set high, so that the fluidity cannot be increased. There was a problem that molding corresponding to the thinning was not possible.

As a method for improving the fluidity of a resin composition containing a semi-aromatic polyamide, there is a method of blending an aliphatic polyamide with the resin composition. However, a resin composition containing a semi-aromatic polyamide may have reduced heat resistance and chemical resistance required for electric / electronic parts due to the inclusion of an aliphatic polyamide. In other words, in recent years, electrical and electronic parts have been used for automobile parts due to the progress of electrification of automobiles. Electric and electronic parts used for automobile parts are gasoline, oil, battery sulfuric acid, wax, Since there is a greater possibility of chemicals such as car wash goods, chemical resistance is also required.
Semi-aromatic polyamide is excellent in heat resistance and chemical resistance, but aliphatic polyamide is inferior in heat resistance and chemical resistance, and a resin composition containing semi-aromatic polyamide is blended with aliphatic polyamide. As a result, although the fluidity is improved, there is a problem that the heat resistance and chemical resistance are lowered.

International Publication No. 2009/017043

  An object of the present invention is to provide a thermoplastic resin composition containing a semi-aromatic polyamide and a flame retardant, in which a decrease in heat resistance and chemical resistance is suppressed, and fluidity is improved. To do.

As a result of intensive studies to solve the above problems, the present inventors have found that a semi-aromatic polyamide resin composition having a specific composition and characteristics can solve the above problems, and have reached the present invention.
That is, the gist of the present invention is as follows.

(1) A total of 100 parts by mass of the semi-aromatic polyamide (A) and the aliphatic polyamide (B),
A thermoplastic resin composition containing 20 to 100 parts by mass of a brominated flame retardant (C) and 2 to 25 parts by mass of an antimony flame retardant auxiliary (D),
The mass ratio (A / B) of the semi-aromatic polyamide (A) and the aliphatic polyamide (B) is 90/10 to 40/60,
The melting point of the semi-aromatic polyamide (A) is 280 ° C. or higher,
A thermoplastic resin composition having a mass increase rate R of 50% or less after being immersed in 50% sulfuric acid at 23 ° C. for 48 hours.
(2) The thermoplastic resin composition according to (1), wherein the aliphatic diamine component in the semiaromatic polyamide (A) is 1,10-decanediamine.
(3) The thermoplastic resin composition according to (1) or (2), wherein the aliphatic polyamide (B) is polyamide 6 and / or polyamide 66.
(4) The mass ratio (C / D) of the brominated flame retardant (C) and the antimony flame retardant auxiliary (D) is 95/5 to 60/40, (1) to (3 ). The thermoplastic resin composition according to any one of
(5) The semi-aromatic polyamide (A) contains an aliphatic monocarboxylic acid component, the aliphatic monocarboxylic acid has 15 to 30 carbon atoms, and the content of the aliphatic monocarboxylic acid component is semi-aromatic. The thermoplastic resin composition according to any one of (1) to (4), wherein the content is 0.3 to 4.0 mol% with respect to all monomers constituting the group polyamide (A).
(6) The thermoplastic resin composition according to any one of (1) to (5), wherein the brominated flame retardant (C) is brominated polystyrene.
(7) The thermoplastic resin composition according to any one of (1) to (6), wherein the antimony flame retardant aid (D) is antimony trioxide.
(8) The thermoplastic resin composition according to any one of (1) to (7), further comprising an anti-drip agent (E).
(9) The thermoplastic resin composition according to any one of (1) to (8), further comprising an inorganic reinforcing material (F).
(10) A molded article obtained by molding the thermoplastic resin composition according to any one of (1) to (9).

  According to the present invention, there is provided a thermoplastic resin composition excellent in fluidity at the time of extrusion and molding, in addition to excellent heat resistance (reflow resistance), chemical resistance, flame retardancy and mechanical properties. Can do.

Hereinafter, the present invention will be described in detail.
The thermoplastic resin composition of the present invention contains a semi-aromatic polyamide (A), an aliphatic polyamide (B), a brominated flame retardant (C) and an antimony flame retardant auxiliary (D).

In the present invention, the semi-aromatic polyamide (A) contains a dicarboxylic acid component and a diamine component as constituent components, the dicarboxylic acid component contains an aromatic dicarboxylic acid, and the diamine component contains an aliphatic diamine. is there.
The dicarboxylic acid component constituting the semi-aromatic polyamide (A) preferably contains terephthalic acid (T), and the content of terephthalic acid is 95 mol% or more in the dicarboxylic acid component from the viewpoint of heat resistance. It is preferable that it is 100 mol%.
The diamine component in the semi-aromatic polyamide (A) is preferably an aliphatic diamine having 8 to 12 carbon atoms from the viewpoints of heat resistance and processability. Examples of the aliphatic diamine having 8 to 12 carbon atoms include 1,8-octanediamine, 1,9-nonanediamine, 1,10-decanediamine, 1,11-undecanediamine, and 1,12-dodecanediamine. Of these, 1,10-decanediamine is preferred because of its high versatility. These may be used alone or in combination, but are preferably used alone from the viewpoint of improving mechanical properties.
In the present invention, specific examples of the semi-aromatic polyamide (A) include, for example, polyamide 8T, polyamide 9T, polyamide 10T, polyamide 11T, and polyamide 12T.

The dicarboxylic acid component of the semi-aromatic polyamide (A) may contain a dicarboxylic acid other than terephthalic acid. Dicarboxylic acids other than terephthalic acid include aromatic dicarboxylic acid components such as phthalic acid, isophthalic acid, naphthalenedicarboxylic acid, oxalic acid, malonic acid, succinic acid, glutaric acid, adipic acid, pimelic acid, suberic acid, azelaic acid And aliphatic dicarboxylic acids such as sebacic acid, undecanedioic acid and dodecanedioic acid, and alicyclic dicarboxylic acids such as cyclohexanedicarboxylic acid. The dicarboxylic acid other than terephthalic acid is preferably 5 mol% or less, and more preferably substantially free from the total number of moles of raw material monomers.
The diamine component of the semi-aromatic polyamide (A) may contain a diamine other than the aliphatic diamine component having 8 to 12 carbon atoms. Examples of other diamines include 1,2-ethanediamine, 1,3-propanediamine, 1,4-butanediamine, 1,5-pentanediamine, 1,6-hexanediamine, 1,7-heptanediamine, Aliphatic diamine components such as 1,13-tridecanediamine, 1,14-tetradecanediamine, 1,15-pentadecanediamine, alicyclic diamines such as cyclohexanediamine, and aromatic diamines such as xylylenediamine and benzenediamine Can be mentioned. The diamine other than the aliphatic diamine component having 8 to 12 carbon atoms is preferably 5 mol% or less, and more preferably substantially free from the total number of moles of the raw material monomers.

  The semi-aromatic polyamide (A) may contain a lactam such as caprolactam or laurolactam, or an ω-aminocarboxylic acid such as aminocaproic acid or 11-aminoundecanoic acid, if necessary.

In the present invention, the semi-aromatic polyamide (A) can contain a monocarboxylic acid as a constituent component, and preferably contains an aliphatic monocarboxylic acid as a constituent component. A molded body obtained from a mixture of a semi-aromatic polyamide (A) having an aliphatic monocarboxylic acid as a constituent and an aliphatic polyamide (B) dispersed therein has a heat resistance in the surface layer of the molded body that is susceptible to heat. High semi-aromatic polyamide (A) is likely to be the main component, and blisters are less likely to occur in the reflow process.
The aliphatic monocarboxylic acid preferably has 15 to 30 carbon atoms, and more preferably 18 to 29 carbon atoms. When the semiaromatic polyamide (A) contains an aliphatic monocarboxylic acid having 15 to 30 carbon atoms, the fluidity is improved, and the semiaromatic polyamide component is likely to be a main component in the surface layer of the molded product. When the carbon number of the monocarboxylic acid is less than 15, the semi-aromatic polyamide (A) may not be able to obtain a fluidity improving effect. On the other hand, if the aliphatic monocarboxylic acid has more than 30 carbon atoms, the semi-aromatic polyamide (A) may be inhibited from crystallizing, and the molding processability and heat resistance may decrease.

Examples of the aliphatic monocarboxylic acid having 15 to 30 carbon atoms include pentadecylic acid, palmitic acid, margaric acid, stearic acid, nonadecylic acid, arachidic acid, behenic acid, lignoceric acid, serotic acid, heptacosanoic acid, montanic acid, Melicic acid is mentioned. Of these, stearic acid, behenic acid, and montanic acid are preferred because of their high versatility.
Aliphatic monocarboxylic acids may be used alone or in combination.

  In the semi-aromatic polyamide (A), the content of the aliphatic monocarboxylic acid component is preferably 0.3 to 4.0 mol% with respect to all monomers constituting the semi-aromatic polyamide (A). More preferably, it is 0.6 to 3.5 mol%. When the content of the aliphatic monocarboxylic acid component is less than 0.3 mol%, the resulting semi-aromatic polyamide (A) has a high molecular weight, generates a decomposition gas during extrusion or molding, and improves fluidity. The effect may not be obtained. On the other hand, when the content of the aliphatic monocarboxylic acid component exceeds 4.0 mol%, the semi-aromatic polyamide (A) may deteriorate in mechanical properties.

  The semi-aromatic polyamide (A) needs to have a melting point of 280 ° C. or higher, preferably 300 ° C. or higher. If the melting point of the semi-aromatic polyamide (A) is less than 280 ° C., the thermoplastic resin composition may melt and deform during reflow.

  The semi-aromatic polyamide (A) preferably has a relative viscosity of 1.5 to 3.5 when measured at 25 ° C. and a concentration of 1 g / dL in 96% sulfuric acid, which is an index of molecular weight. It is more preferably 0.7 to 3.5, and even more preferably 1.9 to 3.1. If the relative viscosity of the semi-aromatic polyamide (A) is less than 1.5, the thermoplastic resin composition may have reduced mechanical properties.

  When the semi-aromatic polyamide resin (A) has higher crystallinity, the resulting molded product has a higher crystallinity and more improved heat resistance, reflow resistance, mechanical strength, and low water absorption. The group polyamide (A) preferably has a crystallinity controlled within a specific range. In the present invention, the crystal melting energy (ΔH) measured using a differential scanning calorimeter (DSC) is used as an index of crystallinity, and ΔH of the semi-aromatic polyamide resin (A) is 50 J / g or more. Is preferable, and it is more preferable that it is 55 J / g or more. When ΔH is less than 50 J / g, the semi-aromatic polyamide resin (A) cannot sufficiently increase the crystallinity, and the resulting molded product may generate blisters in the reflow process.

  The semi-aromatic polyamide (A) can be produced by a conventionally known heat polymerization method or solution polymerization method. A heat polymerization method is preferably used because it is industrially advantageous. As the heat polymerization method, there is a method comprising a step (i) of obtaining a reaction product from a dicarboxylic acid component, a diamine component, and a monocarboxylic acid component, and a step (ii) of polymerizing the obtained reaction product. Can be mentioned.

  As the step (i), for example, dicarboxylic acid powder and monocarboxylic acid are mixed and heated in advance to a temperature not lower than the melting point of diamine and not higher than the melting point of dicarboxylic acid, and the dicarboxylic acid powder and monocarboxylic acid at this temperature are mixed. In addition, a method of adding diamine without substantially containing water so as to keep the state of the dicarboxylic acid powder may be mentioned. Alternatively, as another method, a suspension of a molten diamine and a solid dicarboxylic acid is stirred and mixed to obtain a mixed solution, and then at a temperature lower than the melting point of the semiaromatic polyamide to be finally produced. And a method of obtaining a mixture of a salt and a low polymer by carrying out a salt formation reaction by the reaction of a dicarboxylic acid, a diamine and a monocarboxylic acid and a low polymer production reaction by polymerization of the produced salt. In this case, crushing may be performed while the reaction is performed, or crushing may be performed after the reaction is once taken out. As the step (i), the former is preferable because the shape of the reaction product can be easily controlled.

  As the step (ii), for example, the reaction product obtained in the step (i) is solid-phase polymerized at a temperature lower than the melting point of the semi-aromatic polyamide to be finally produced to increase the molecular weight to a predetermined molecular weight. And a method for obtaining a semi-aromatic polyamide. The solid phase polymerization is preferably performed in a stream of inert gas such as nitrogen at a polymerization temperature of 180 to 270 ° C. and a reaction time of 0.5 to 10 hours.

  The reaction apparatus in step (i) and step (ii) is not particularly limited, and a known apparatus may be used. Step (i) and step (ii) may be performed by the same apparatus or may be performed by different apparatuses.

  In the production of the semi-aromatic polyamide (A), a polymerization catalyst may be used in order to increase the efficiency of polymerization. Examples of the polymerization catalyst include phosphoric acid, phosphorous acid, hypophosphorous acid, and salts thereof. In general, the addition amount of the polymerization catalyst is preferably 2 mol% or less with respect to all monomers constituting the semi-aromatic polyamide (A).

  The aliphatic polyamide (B) in the present invention is a polyamide which does not contain an aromatic component in the main chain. For example, poly ε-capramide (polyamide 6), polytetramethylene adipamide (polyamide 46), polyhexamethylene Adipamide (polyamide 66), polyhexamethylene sebamide (polyamide 610), polyhexamethylene dodecamide (polyamide 612), polyundecamethylene adipamide (polyamide 116), polyundecanamide (polyamide 11), Examples thereof include polydodecanamide (polyamide 12), a polyamide copolymer containing at least two different polyamide components, or a mixture thereof. Of these, polyamides having 6 or less carbon atoms are preferred, and polyamide 6, polyamide 46, and polyamide 66 are preferred from the viewpoints of fluidity and economy.

  The relative viscosity of the aliphatic polyamide (B) is not particularly limited, and may be appropriately set depending on the purpose. For example, in order to obtain a thermoplastic resin composition that can be easily molded, the aliphatic polyamide (B) preferably has a relative viscosity of 1.9 to 4.0, and is preferably 2.0 to 3.5. It is more preferable. If the relative viscosity of the aliphatic polyamide (B) is less than 1.9, the toughness may be insufficient depending on the molded article, and the mechanical characteristics may be deteriorated. On the other hand, when the relative viscosity of the aliphatic polyamide (B) exceeds 4.0, the thermoplastic resin composition may be difficult to mold, and the resulting molded product may be inferior in appearance.

  The mass ratio (A / B) of the semi-aromatic polyamide (A) and the aliphatic polyamide (B) needs to be 90/10 to 40/60, and should be 90/10 to 46/54. Preferably, it is 90 / 10-50 / 50, more preferably 80 / 20-50 / 50. If the semi-aromatic polyamide (A) exceeds 90% by mass, that is, if the aliphatic polyamide (B) is less than 10% by mass, the fluidity of the thermoplastic resin composition may decrease. On the other hand, when the semi-aromatic polyamide (A) is less than 40% by mass, that is, when the aliphatic polyamide (B) exceeds 60% by mass, the reflow resistance of the thermoplastic resin composition may be lowered.

  In the brominated flame retardant (C) in the present invention, the content of bromine atoms contained in the compound is preferably 50% by mass or more, and more preferably 58% by mass or more. If the bromine-based flame retardant (C) has a bromine atom content of less than 50% by mass, the brominated flame retardant (C) increases in content to impart the required flame retardancy, and the mechanical properties of the thermoplastic resin composition May decrease or the generation amount of cracked gas may increase.

  Examples of the brominated flame retardant (C) include hexabromocyclododecane, bis (dibromopropyl) tetrabromo-bisphenol A, bis (dibromopropyl) tetrabromo-bisphenol S, tris (dibromopropyl) isocyanurate, and tris (tribromoneo). Pentyl) phosphate, decabromodiphenylene oxide, brominated epoxy resin, bis (pentabromophenyl) ethane, tris (tribromophenoxy) triazine, ethylenebis (tetrabromophthal) imide, ethylenebispentabromophenyl, porbromophenylindane , Brominated polystyrene, TBBA polycarbonate, brominated polyphenylene oxide, and polypentabromobenzyl acrylate. Among these, ethylene bis (tetrabromophthal) imide, brominated epoxy resin, and brominated polystyrene that can withstand processing at high temperatures are preferable, and brominated polystyrene is more preferable. Specific product names of brominated polystyrene include, for example, “Great Lakes CP-44HF”, “Great Lakes PBS-64HW”, “Great Lakes PDBS-80” manufactured by Chemtura, “SAYTEX HP-7010” manufactured by Albemarle. “SAYTEX HP-3010” may be mentioned. These may be used alone or in combination.

  The content of the brominated flame retardant (C) needs to be 20 to 100 parts by mass with respect to 100 parts by mass in total of the semi-aromatic polyamide (A) and the aliphatic polyamide (B), and 30 to It is preferably 90 parts by mass. If the content of the brominated flame retardant (B) is less than 20 parts by mass, the effect of improving flame retardancy cannot be obtained. On the other hand, when the content of the brominated flame retardant (B) exceeds 100 parts by mass, the thermoplastic resin composition is excellent in flame retardancy, but the generation of decomposition gas during extrusion and molding increases.

  Examples of the antimony flame retardant aid (D) in the present invention include antimony trioxide, antimony tetraoxide, and antimony pentoxide. Of these, antimony trioxide, which has a high synergistic effect with the brominated flame retardant (C) and can suppress generation of the amount of cracked gas, is preferable. Specific examples of the product name include “PATOX-M” (antimony trioxide) manufactured by Nippon Seiko Co., Ltd. These may be used alone or in combination.

  The content of the antimony flame retardant auxiliary (D) needs to be 2 to 25 parts by mass with respect to a total of 100 parts by mass of the semi-aromatic polyamide (A) and the aliphatic polyamide (B), It is preferable that it is 5-20 mass parts. If the content of the antimony flame retardant auxiliary (D) is less than 2 parts by mass, the effect of improving flame retardancy cannot be obtained. On the other hand, when the content of the antimony flame retardant auxiliary (D) exceeds 25 parts by mass, the resulting thermoplastic resin composition has poor mechanical properties and operability during extrusion.

  The mass ratio (C / D) of the brominated flame retardant (C) and the antimony flame retardant auxiliary (D) used in the present invention is preferably 95/5 to 60/40, and 90/10 to 70 / 30 is more preferable. When the brominated flame retardant (C) is 95% by mass or less, flame retardancy can be improved. If the bromine-based flame retardant (C) is less than 60% by mass, even if the mass ratio of the antimony-based flame retardant aid (D) is increased, the effect of improving flame retardancy reaches saturation, which is economically disadvantageous. It may become.

  The thermoplastic resin composition of the present invention may contain an anti-drip agent (E). A known compound can be used as the anti-drip agent (E) if it has an effect of preventing dripping during combustion. Examples of the anti-drip agent (E) include polytetrafluoroethylene, polyhexafluoropropylene, tetrafluoroethylene-hexafluoropropylene copolymer, tetrafluoroethylene-perfluoroalkyl vinyl ether copolymer, tetrafluoroethylene-ethylene copolymer. Examples thereof include polymers, hexafluoropropylene-propylene copolymers, polyvinylidene fluoride, vinylidene fluoride-ethylene copolymers, polychlorotrifluoroethylene, and modified polytetrafluoroethylene. Of these, polytetrafluoroethylene and modified polytetrafluoroethylene, which have a high anti-dripping effect, are preferred. Specific product names include, for example, “Polyflon MPA FA-500H” (polytetrafluoroethylene) manufactured by Daikin Industries, Ltd., “Metabrene A-3750”, “Metabrene A-3800” (modified polytetrafluoroethylene) manufactured by Mitsubishi Rayon Co., Ltd. Ethylene). These may be used alone or in combination.

  The content of the anti-drip agent (E) is preferably 0.3 to 3.0 parts by mass with respect to 100 parts by mass in total of the semi-aromatic polyamide (A) and the aliphatic polyamide (B). More preferably, it is 3 to 2.5 parts by mass. When the content of the anti-drip agent (E) is less than 0.3 parts by mass, the effect of preventing dripping at the time of combustion is not sufficient. When the content exceeds 3.0 parts by mass, the thermoplastic resin composition is melted. Kneading may be difficult.

The thermoplastic resin composition of the present invention may further contain an inorganic reinforcing material (F). A fibrous reinforcement is mentioned as an inorganic reinforcement (F).
Examples of the fibrous reinforcing material include glass fiber, carbon fiber, boron fiber, asbestos fiber, polyvinyl alcohol fiber, polyester fiber, acrylic fiber, aramid fiber, polybenzoxazole fiber, kenaf fiber, bamboo fiber, hemp fiber, bagasse fiber. High strength polyethylene fiber, alumina fiber, silicon carbide fiber, potassium titanate fiber, brass fiber, stainless steel fiber, steel fiber, ceramic fiber, and basalt fiber. Among them, glass fiber, carbon fiber, and aramid fiber are preferable because they have a high effect of improving mechanical properties, have heat resistance that can withstand the heating temperature during melt kneading with polyamide, and are easily available. Specific product names of glass fibers include, for example, “CS3G225S” manufactured by Nittobo Co., Ltd. and “T-781H” manufactured by Nippon Electric Glass Co., Ltd. Specific examples of product names of carbon fibers include, for example, Toho Tenax “HTA-C6-NR” manufactured by the company may be mentioned. The fibrous reinforcing material may be used alone or in combination.

  The fiber length and fiber diameter of the fibrous reinforcing material are not particularly limited, but the fiber length is preferably 0.1 to 7 mm, and more preferably 0.5 to 6 mm. By setting the fiber length of the fibrous reinforcing material to 0.1 to 7 mm, the resin composition can be reinforced without adversely affecting the moldability. The fiber diameter is preferably 3 to 20 μm, and more preferably 5 to 13 μm. By setting the fiber diameter to 3 to 20 μm, the resin composition can be efficiently reinforced without breaking during melt kneading. Examples of the cross-sectional shape include a circular shape, a rectangular shape, an oval shape, and other irregular cross-sections. Among them, a circular shape is preferable.

  As the inorganic reinforcing material (F), in addition to the fibrous reinforcing material, an acicular reinforcing material or a plate-like reinforcing material may be used. In particular, by using a fibrous reinforcing material together with a needle-like reinforcing material or a plate-like reinforcing material, it is possible to reduce the warping of the molded body or improve the drip resistance during a flame retardant test. Examples of the acicular reinforcing material include wollastonite, potassium titanate whisker, zinc oxide whisker, and magnesium sulfate whisker. Examples of the plate-like reinforcing material include talc, mica, and glass flakes.

  The content of the inorganic reinforcing material (F) is preferably 5 to 200 parts by mass with respect to 100 parts by mass in total of the semi-aromatic polyamide (A) and the aliphatic polyamide (B), and 5 to 180 parts by mass. It is more preferable that it is 10 to 170 parts by mass. If the content of the inorganic reinforcing material (F) is less than 5 parts by mass, the reinforcing effect of the mechanical strength may not be sufficient, and if it exceeds 200 parts by mass, the reinforcing efficiency of the mechanical strength is reduced, In the plastic resin composition, workability at the time of melt-kneading may be reduced, or it may be difficult to obtain pellets.

  The thermoplastic resin composition of the present invention may further contain an antioxidant (G). Examples of the antioxidant (G) include phosphorus-based antioxidants, hindered phenol-based antioxidants, hindered amine-based antioxidants, triazine-based compounds, and sulfur-based compounds. Among these, phosphorus-based antioxidants are used. preferable. When the thermoplastic resin composition containing the inorganic reinforcing material (F) stays in a high-temperature cylinder for a long time, when the inorganic reinforcing material (F) is surface-treated, the surface treatment agent is thermally decomposed, May cause a decrease in mechanical strength. However, in the present invention, when the resin composition is accumulated for a long time in the cylinder, that is, when the molding cycle is long at the time of injection molding or even when the resin is retained in the cylinder for a long time with a small injection amount. By containing an inhibitor (G), the fall of the tensile strength of the said resin composition can be suppressed. The antioxidant (G) is usually contained for the purpose of lowering the molecular weight or deteriorating the color of the semi-aromatic polyamide (A). In the present invention, in addition to these effects, the residence stability of the resin composition can be improved. When it contains antioxidant (G), it is preferable that the content is 0.1-5 mass parts with respect to 100 mass parts of semi-aromatic polyamide (A), 0.2-5 mass parts More preferably.

  The phosphorus-based antioxidant may be an inorganic compound or an organic compound, and is not particularly limited. For example, monosodium phosphate, disodium phosphate, trisodium phosphate, sodium phosphite, calcium phosphite, phosphorous acid Inorganic phosphates such as magnesium phosphate and manganese phosphite, triphenyl phosphite, trioctadecyl phosphite, tridecyl phosphite, trinonylphenyl phosphite, diphenylisodecyl phosphite, bis (2,6-di-tert) -Butyl-4-methylphenyl) pentaerythritol diphosphite, tris (2,4-di-tert-butylphenyl) phosphite, distearyl pentaerythritol diphosphite, bis (nonylphenyl) pentaerythritol diphosphite, tetrakis (2,4- -t- butyl phenyl) -4,4-biphenylene Li range phosphite and the like. Among them, bis (2,6-di-tert-butyl-4-methylphenyl) pentaerythritol diphosphite and tetrakis (2,4-di-tert-butylphenyl) -4,4-biphenylylene diphosphite are preferable. . Specific product names include, for example, “ADEKA STAB PEP-36” (bis (2,6-di-tert-butyl-4-methylphenyl) pentaerythritol diphosphite), “ADEKA STAB PEP-8” manufactured by Adeka Corporation. (Distearyl pentaerythritol diphosphite), “adekastab PEP-4C” (bis (nonylphenyl) pentaerythritol diphosphite), “Hostanox P-EPQ” (tetrakis (2,4-di-t-) manufactured by Clariant) Butylphenyl) -4,4-biphenylylene phosphite). These may be used alone or in combination.

  The thermoplastic resin composition of the present invention may further contain other polymers as necessary. Other polymers include, for example, alicyclic polyamides such as polyamide 9C, polyethylene terephthalate, polybutylene terephthalate, liquid crystal polymer, polyarylate, polycyclohexanedimethylene terephthalate and other polyesters, polyethylene, polystyrene, polypropylene and other polyolefins, polyphenylene sulfide , Polyphenylene ether, and polyether ether ketone.

  In addition, the thermoplastic resin composition of this invention may contain another additive as needed. Other additives include, for example, fillers such as talc, swellable clay minerals, silica, alumina, glass beads, graphite, pigments, dyes, antistatic agents, plate reinforcements, thermal stabilizers, impact resistance improvers. , Plasticizers, mold release agents, lubricants, crystal nucleating agents, organic peroxides, terminal blockers, and slidability improvers. The method for adding other additives is not particularly limited as long as the effect is not impaired. For example, the additives are added during polymerization of the polyamide or during melt kneading.

Moreover, the thermoplastic resin composition of the present invention may contain a light stabilizer. When a molded product of a thermoplastic resin composition containing a white pigment such as titanium oxide is used outdoors as an exhaust finisher or an LED reflector, titanium oxide may promote photodecomposition, so the thermoplastic resin composition is light. It is preferable to contain a stabilizer. Examples of the light stabilizer include benzophenone compounds, benzotriazole compounds, salicylate compounds, hindered amine compounds, and hindered phenol compounds. Among these, hindered amine compounds are preferable. When the light stabilizer is contained, the content thereof is preferably 0.1 to 5 parts by mass, more preferably 0.2 to 5 parts by mass with respect to 100 parts by mass of the thermoplastic resin composition. . A thermoplastic resin composition can improve light stability by containing 0.1-5 mass parts of light stabilizers.
The thermoplastic resin composition is preferably used in combination with a light stabilizer and an antioxidant. By using the thermoplastic resin composition in combination, the residence stability at the time of molding is improved, and the light deterioration due to ultraviolet rays or the like at the time of use is efficiently prevented. be able to.

The thermoplastic resin composition of the present invention comprises the above components and is manufactured by the following manufacturing method, in addition to excellent heat resistance (reflow resistance), chemical resistance, flame resistance, and mechanical properties. Excellent fluidity during extrusion and molding.
In the present invention, the chemical resistance is evaluated by a mass increase rate R after immersion in a sulfuric acid immersion test in which a thermoplastic resin composition is immersed in 50% sulfuric acid at 23 ° C. for 48 hours, and the mass increase rate R is 50% or less. It is preferably 45% or less, more preferably 40% or less, and even more preferably 30% or less. When the mass increase rate R exceeds 50%, it may be difficult to use the resulting molded article for an automotive part or the like where chemicals may adhere.

In the present invention, the method for mixing the raw materials is not particularly limited, but the melt-kneading method is preferable. Examples of the melt-kneading method include a method using a batch kneader such as Brabender, a Banbury mixer, a Henschel mixer, a helical rotor, a roll, a single screw extruder, and a twin screw extruder. The melt kneading temperature is selected from a region where the semi-aromatic polyamide (A) melts and does not decompose. If the kneading temperature is too high, the semi-aromatic polyamide (A) not only decomposes but also the aliphatic polyamide (B) and brominated flame retardant (C) may be decomposed. The melting point (Tm) of the aromatic polyamide (A) is preferably (Tm−20 ° C.) to (Tm + 50 ° C.).
In the melt-kneading, the semi-aromatic polyamide (A) is first melted, and then the aliphatic polyamide (B) is additionally supplied to the melt-kneader so that the semi-aromatic polyamide (A) and the aliphatic polyamide (B ) Is preferably mixed. Specifically, for example, a semi-aromatic polyamide (A), a flame retardant, or the like is supplied from the base (main supply port) of a twin-screw extruder, melted, and then used in the middle of the extruder using a side feeder or the like. For example, a method of supplying the aliphatic polyamide (B).

  As the granulation method of the thermoplastic resin composition of the present invention, the melt is extruded into a strand shape into a pellet shape, the melt is hot cut, underwater cut into a pellet shape, or into a sheet shape. Examples thereof include a method of extrusion cutting and a method of extruding and pulverizing into a block shape to form a powder.

  Examples of the molding method of the thermoplastic resin composition of the present invention include, for example, an injection molding method, an extrusion molding method, a blow molding method, and a sintering molding method, and since the effect of improving mechanical properties and moldability is great, An injection molding method is preferred. Although it does not specifically limit as an injection molding machine, For example, a screw in-line type injection molding machine or a plunger type injection molding machine is mentioned. The thermoplastic resin composition heated and melted in the cylinder of the injection molding machine is weighed for each shot, injected into the mold in a molten state, cooled to a predetermined shape, solidified, and then molded as a molded body. Taken from. The resin temperature at the time of injection molding is preferably (Tm) to (Tm + 50 ° C.). In addition, when the thermoplastic resin composition is heated and melted, it is preferable to use a sufficiently dried thermoplastic resin composition pellet.

  The thermoplastic resin composition of the present invention can be used in a wide range of applications such as automobile parts, electric / electronic parts, general merchandise, civil engineering and building articles, and is particularly suitable for electric / electronic parts because of its excellent flame retardancy. . Examples of the automobile parts include a thermostat cover, an IGBT module member of an inverter, an insulator member, an exhaust finisher, a power device housing, an ECU housing, an ECU connector, a motor and a coil insulating material, and a cable covering material. Examples of electrical / electronic components include connectors, LED reflectors, switches, sensors, sockets, capacitors, jacks, fuse holders, relays, coil bobbins, breakers, electromagnetic switches, holders, plugs, portable personal computers and word processors. Housing parts, resistors, ICs, and LED housings.

  EXAMPLES Hereinafter, although an Example demonstrates this invention concretely, this invention is not limited by these Examples.

1. Measurement method The physical properties of the semi-aromatic polyamide and the thermoplastic resin composition were measured by the following methods.

(1) Relative viscosity Measured at a concentration of 1 g / dL and 25 ° C. using 96 mass% sulfuric acid as a solvent.

(2) Melting point and crystal melting energy of semi-aromatic polyamide (A) Using a differential scanning calorimeter DSC-7 manufactured by PerkinElmer Co., Ltd., heated to 350 ° C. at a heating rate of 20 ° C./min, then 350 ° C. For 5 minutes, and the temperature was decreased to 25 ° C. at a temperature decrease rate of 20 ° C./min. Then, after maintaining at 25 ° C. for 5 minutes, the top of the endothermic peak when the temperature rise was measured again at a rate of temperature rise of 20 ° C./min was defined as the melting point (Tm). Further, a value obtained by dividing the endothermic peak area by the mass of the sample was defined as crystal melting energy (ΔH).

(3) Melt flow rate (MFR)
According to JIS K7210, measurement was performed at 340 ° C. and a load of 1.2 kgf.

(4) Mechanical properties The thermoplastic resin composition was injection molded using an injection molding machine S2000i-100B type (manufactured by FANUC) to produce a test piece (dumbbell piece). The cylinder temperature was melting point (Tm) + 15 ° C., and the mold temperature was 135 ° C.
Using the obtained test piece, bending strength and bending elastic modulus were measured according to ISO178.
Practically, the bending strength is preferably 110 MPa or more, more preferably 120 MPa or more, and further preferably 140 MPa or more. Moreover, practically, the flexural modulus is preferably 3 GPa or more, and more preferably 5 GPa or more.

(5) Bar flow fluidity The thermoplastic resin composition was subjected to cylinder temperature (Tm + 15 ° C.), mold temperature 135 ° C., injection pressure 150 MPa, injection time 8 using an injection molding machine S2000i-100B type (manufactured by FANUC). Second, the flow length of the test piece when molded at a set injection speed of 150 mm / second was measured and used as the bar flow flow length. As the mold, a bar flow test mold having a thickness of 0.5 mm, a width of 20 mm, and a total length of 980 mm was used. Bar flow length is an indicator of liquidity. Practically, the bar flow flow length is preferably 100 mm or more, more preferably 110 mm or more.

(6) Flame retardancy Using an injection molding machine J35AD (manufactured by Nippon Steel Works), a plate shape of 127 mm × 12.7 mm × thickness 0.8 mm under conditions of cylinder temperature (Tm + 25 ° C.) and mold temperature 135 ° C. A test piece was prepared. Furthermore, a plate-shaped test piece of 127 mm × 12.7 mm × thickness 0.4 mm was produced.
Using the obtained test piece, evaluation was performed in accordance with the standards of UL94 shown in Table 1 (standards defined by Under Writers Laboratories Inc., USA). When it did not satisfy any standard, it was set as not V-2. Practically, V-0 is preferable at a thickness of 0.8 mm, and V-0 is more preferable at a thickness of 0.4 mm.

(7) Chemical resistance (sulfuric acid immersion test)
Using an injection molding machine J35AD (manufactured by Nippon Steel Works), a plate-like test piece of 20 mm × 20 mm × thickness 0.5 mm was produced under the conditions of cylinder temperature (Tm + 25 ° C.) and mold temperature 135 ° C. The obtained test piece was immersed in 50% sulfuric acid for 48 hours in an environment of 23 ° C., the mass before and after the immersion treatment was measured, and the mass increase rate R represented by the following formula was calculated.
R = (Wp−Wi) / ((1−Cf / 100) × Wi) × 100
Wp: Test piece mass after immersion treatment (g)
Wi: Mass of test specimen before immersion treatment (g)
Cf: content (% by mass) of the inorganic reinforcing material (F) in the thermoplastic resin composition

(8) Heat resistance (Reflow resistance)
The test piece prepared by the method described in (7) above was left in a constant temperature and humidity chamber (FH14C type manufactured by ETAC) at 85 ° C. and 85% RH for 168 hours, and a reflow tester (FT-02 manufactured by CIF).
The appearance change was confirmed. The temperature conditions of the reflow tester were controlled by preheating (150 ° C.-220 ° C., 115 seconds), reflow (220 ° C. or more, 50 seconds), and maximum temperature during reflow (260 ° C., within 10 seconds). The case where the appearance did not change was evaluated as ◯, and the case where blistering occurred was evaluated as ×.

2. Raw materials The raw materials used in Examples and Comparative Examples are shown below.

(1) Semi-aromatic polyamide (A)
・ Semi-aromatic polyamide (A-1)
Ribbon blender containing 4.70 kg of powdered terephthalic acid (TPA) as an aromatic dicarboxylic acid component, 0.33 kg of stearic acid (STA), and 9.3 g of sodium hypophosphite monohydrate as a polymerization catalyst It put into the reaction apparatus of a type | formula, and it heated at 170 degreeC, stirring with a rotation speed of 30 rpm under nitrogen sealing. Thereafter, 4.97 kg of 1,10-decanediamine (DDA) 4.97 kg heated to 100 ° C. as a diamine component using a liquid injection device while maintaining the temperature at 170 ° C. and the rotation speed at 30 rpm. Added continuously over 5 hours (continuous liquid injection method) to obtain a reaction product. The molar ratio of the raw material monomers was TPA: DDA: STA = 48.5: 49.6: 1.9 (the equivalent ratio of functional groups was TPA: DDA: STA = 49: 50: 1).
Subsequently, the obtained reaction product was polymerized by heating at 250 ° C. and a rotation speed of 30 rpm for 8 hours under a nitrogen stream in the same reaction apparatus to prepare a semi-aromatic polyamide powder.
Thereafter, the obtained semi-aromatic polyamide powder is made into a strand using a twin-screw kneader, and the strand is cooled and solidified through a water tank, which is cut with a pelletizer to produce a semi-aromatic polyamide (A-1). Pellets were obtained.

Semi-aromatic polyamide (A-2) to (A-9)
Except having changed the resin composition as shown in Table 2, operation similar to the case where semi-aromatic polyamide (A-1) was produced was performed, and semi-aromatic polyamide was obtained.

  The resin composition and characteristic values of the obtained semi-aromatic polyamide are shown in Table 2.

(2) Aliphatic polyamide B-1: Polyamide 6, Unitika A1015, relative viscosity 2.02
B-2: Polyamide 66, Leona 1200 manufactured by Asahi Kasei Chemicals Corporation, relative viscosity 2.45
B-3: Polyamide 46, TW300 manufactured by DSM, relative viscosity 2.75

(3) Brominated flame retardant C-1: Brominated polystyrene, PDBS-80 manufactured by Chemtura, bromine content 59%
C-2: Brominated polystyrene, manufactured by Chemtura, PBS-64HW, bromine content 64%

(4) Flame retardant aid D-1: Antimony trioxide, manufactured by Nippon Seiko Co., Ltd. PATOX-M
D-2: aluminum phosphinate salt flame retardant, Exorit OP1230 manufactured by Clariant Chemicals

(5) Anti-drip agent E-1: Polytetrafluoroethylene, manufactured by Daikin Industries, Ltd. Polyflon MPA FA500H
E-2: acrylic-modified polytetrafluoroethylene, Mitsubishi Rayon Co., Ltd. METABLEN A-3750

(6) Inorganic reinforcing material F-1: Glass fiber, Nittobo CS3G225S, average fiber diameter 9.5 μm, average fiber length 3 mm

(7) Antioxidant G-1: Tetrakis (2,4-di-tert-butylphenyl) 4,4'-biphenylene-di-phosphonite, Hostarianx P-EPQ manufactured by Clariant

Example 1
90 parts by mass of semi-aromatic polyamide (A-1), 48 parts by mass of brominated flame retardant (C-1), 11 parts by mass of antimony flame retardant auxiliary (D-1), anti-drip agent (E-1) 1 .8 parts by mass and 0.5 parts by mass of the antioxidant (G-1) are dry blended and weighed using a loss-in-weight continuous quantitative feeder CE-W-1 (manufactured by Kubota Corporation), and the screw diameter It was supplied to the main supply port of a TEM26SS type (manufactured by TOSHIBA MACHINERY CO., LTD.), A 26 mm, L / D50 same-direction twin screw extruder, and melt kneaded. In the middle, 10 parts by mass of the aliphatic polyamide (B-1) was supplied from the side feeder 1, and 68 parts by mass of the inorganic reinforcing material (F-1) was further supplied from the downstream side feeder 2, followed by further kneading. After taking up into a strand form from the die, it was cooled and solidified through a water tank, and cut with a pelletizer to obtain a thermoplastic resin composition pellet. The barrel temperature of the extruder was 310 to 340 ° C., the screw rotation speed was 250 rpm, and the discharge amount was 25 kg / hour.

Examples 2-28, Comparative Examples 1, 4-10
The same operation as in Example 1 was performed except that the composition of the resin composition was changed as shown in Tables 3 to 4. In Example 24, no anti-drip agent (E) was added to the dry blend, Comparative Example 1 did not supply the aliphatic polyamide (B) from the side feeder 1, and Comparative Examples 5 and 6 were dry blends. In this case, no brominated flame retardant (C) was added.

Comparative Example 2
Without supplying 54 parts by mass of aliphatic polyamide (B-1) from side feeder 1, semi-aromatic polyamide (A-1), brominated flame retardant (C-1), antimony flame retardant auxiliary (D- 1) Dry blend 54 parts by weight of an aliphatic polyamide (B-1) together with an anti-drip agent (E-1) and an antioxidant (G-1) and supply them to the main supply port of the same-direction twin screw extruder Then, melt-kneading was carried out in the same manner as in Example 6 except that the inorganic reinforcing material (F-1) was supplied from the downstream side feeder 2 to obtain thermoplastic resin composition pellets.

Comparative Example 3
A thermoplastic resin composition pellet was obtained in the same manner as in Comparative Example 2 except that the mass ratio of the semi-aromatic polyamide (A-1) and the aliphatic polyamide (B-1) was changed.

  The compositions of the thermoplastic resin composition and the obtained properties are shown in Tables 3 and 4.

  In the thermoplastic resin compositions of Examples 1 to 28, the content of the constituent components is in the range specified in the present invention, and the aliphatic polyamide (B) is supplied by a side feeder and melt-kneaded. It was excellent in heat resistance, chemical resistance, flame retardancy, mechanical properties and fluidity.

Since the resin composition of Comparative Example 1 did not contain the aliphatic polyamide (B), the fluidity was low.
Since the resin compositions of Comparative Examples 2 and 3 contained the aliphatic polyamide (B), the fluidity was improved, but the aliphatic polyamide (B) was not side-feeded, and the semi-aromatic polyamide ( Since it was supplied at the same time as A) and melt-kneaded, the chemical resistance was low, blisters were generated even during reflow, and the heat resistance was low.
Since the resin composition of Comparative Example 4 contained too much aliphatic polyamide (B), the chemical resistance and heat resistance were low.
Since the resin compositions of Comparative Examples 5 and 6 do not contain a brominated flame retardant (C), even if a phosphorus flame retardant is used in combination as a flame retardant auxiliary, the antimony flame retardant auxiliary (D) is also contained. Even if the amount was increased, the chemical resistance and heat resistance were low.
Since the resin composition of Comparative Example 7 has a low content of bromine-based flame retardant (C), and Comparative Example 9 has a low content of antimony-based flame retardant aid (D), the thickness is 0.8 mm. The flame retardancy of the test piece was V-1.
In Comparative Example 8, the content of brominated flame retardant (C) is large, and in Comparative Example 10, the content of antimony flame retardant auxiliary (D) is large. Due to the difficulty, pellets of the resin composition could not be obtained.

Claims (10)

A total of 100 parts by weight of semi-aromatic polyamide (A) and aliphatic polyamide (B),
A thermoplastic resin composition containing 20 to 100 parts by mass of a brominated flame retardant (C) and 2 to 25 parts by mass of an antimony flame retardant auxiliary (D),
The mass ratio (A / B) of the semi-aromatic polyamide (A) and the aliphatic polyamide (B) is 90/10 to 40/60,
The melting point of the semi-aromatic polyamide (A) is 280 ° C. or higher,
A thermoplastic resin composition having a mass increase rate R of 50% or less after being immersed in 50% sulfuric acid at 23 ° C. for 48 hours.   The thermoplastic resin composition according to claim 1, wherein the aliphatic diamine component in the semi-aromatic polyamide (A) is 1,10-decanediamine.   The thermoplastic resin composition according to claim 1 or 2, wherein the aliphatic polyamide (B) is polyamide 6 and / or polyamide 66.   The mass ratio (C / D) of the brominated flame retardant (C) and the antimony based flame retardant auxiliary (D) is 95/5 to 60/40. The thermoplastic resin composition as described.   The semiaromatic polyamide (A) contains an aliphatic monocarboxylic acid component, the aliphatic monocarboxylic acid has 15 to 30 carbon atoms, and the content of the aliphatic monocarboxylic acid component is a semiaromatic polyamide ( It is 0.3-4.0 mol% with respect to all the monomers which comprise A), The thermoplastic resin composition in any one of Claims 1-4 characterized by the above-mentioned.   The thermoplastic resin composition according to any one of claims 1 to 5, wherein the brominated flame retardant (C) is brominated polystyrene.   The thermoplastic resin composition according to any one of claims 1 to 6, wherein the antimony flame retardant aid (D) is antimony trioxide.   The thermoplastic resin composition according to any one of claims 1 to 7, further comprising an anti-drip agent (E).   Furthermore, an inorganic reinforcing material (F) is contained, The thermoplastic resin composition in any one of Claims 1-8 characterized by the above-mentioned. A molded article obtained by molding the thermoplastic resin composition according to claim 1.