JP2020033548A - Semi-aromatic polyamide resin composition and molded article obtained by molding the same - Google Patents

Abstract

To provide a semi-aromatic polyamide resin composition which highly suppresses heat aging under a temperature atmosphere of about 100-160°C.SOLUTION: The semi-aromatic polyamide resin composition contains: 100 pts.mass of a semi-aromatic polyamide (A) containing an aromatic dicarboxylic acid component and an aliphatic diamine component and having a melting point of 280-350°C; 0.01-2 pts.mass of a copper compound (B); 0.1-5 pts.mass of an alkali metal halide compound (C); and 0.05-10 pts.mass of a polyhydric alcohol (D).SELECTED DRAWING: None

Description

  The present invention relates to a semi-aromatic polyamide resin composition.

  Semi-aromatic polyamides are widely used as molding materials because of their excellent heat resistance and mechanical properties. Above all, semi-aromatic polyamides having a melting point of 300 ° C. or more are used for applications that have particularly high demands on heat resistance, such as around automobile engines and LED lighting.

  In general, it is known that the higher the melting point of a semi-aromatic polyamide, the lower the fluidity during melt processing, and the lower the physical properties (heat aging) in a high-temperature environment.

Patent Literatures 1 and 2 disclose techniques for suppressing heat aging by adding a copper compound and an alkali metal halide compound to a semi-aromatic polyamide. Patent Literatures 3 to 5 disclose techniques for suppressing thermal aging by adding a polyhydric alcohol to an aliphatic polyamide or a semi-aromatic polyamide. Conventionally, the heat aging test of the resin composition has a time limit, and it is possible to carry out the heat aging test at a temperature higher than the originally used environmental temperature on the assumption that the progress of the heat aging progresses at a higher temperature. In general, the technology disclosed above shows that thermal aging can be effectively suppressed when the ambient temperature is approximately 200 ° C. or higher.
However, the effect of suppressing the heat aging due to the additive has a temperature dependency, so when the temperature is lower than 200 ° C, the effect may be low, and in a relatively low temperature range of about 100 to 160 ° C, A technique for imparting heat aging resistance to a semi-aromatic polyamide for a long time has not been actually established.

JP-A-2003-055549 JP-A-2015-061892 JP 2011-529991 A JP-T-2013-538927 WO 2015/159834

  An object of the present invention is to solve the above-mentioned problem, and an object of the present invention is to provide a semi-aromatic polyamide resin composition in which thermal aging in a temperature atmosphere of about 100 to 160 ° C. is highly suppressed.

  The present inventors have conducted intensive studies to solve the above-mentioned problems, and as a result, it has been found that the above-mentioned problems can be solved by blending a specific amount of a copper compound, an alkali metal halide compound and a polyhydric alcohol with a semi-aromatic polyamide. And arrived at the present invention. That is, the gist of the present invention is as follows.

(1) 100 parts by mass of a semi-aromatic polyamide (A) containing an aromatic dicarboxylic acid component and an aliphatic diamine component and having a melting point of 280 to 350 ° C, 0.01 to 2 parts by mass of a copper compound (B), A semi-aromatic polyamide resin composition comprising 0.1 to 5 parts by mass of an alkali metal halide compound (C) and 0.05 to 10 parts by mass of a polyhydric alcohol (D).
(2) The semi-aromatic polyamide resin composition according to (1), wherein a tensile strength retention after 3,000 hours at 150 ° C. in an air atmosphere is 95% or more.
(3) The semi-aromatic polyamide resin composition according to (1) or (2), further comprising 0.1 to 100 parts by mass of talc (E).
(4) The semi-aromatic polyamide (A) contains a monocarboxylic acid component, and the content thereof is 0.3 to 4.0 mol based on all monomer components constituting the semi-aromatic polyamide (A). % Of the semi-aromatic polyamide resin composition according to any one of (1) to (3).
(5) The semi-aromatic polyamide resin composition according to any one of (1) to (4), wherein the polyhydric alcohol (D) is dipentaerythritol or a derivative thereof.
(6) The semi-aromatic polyamide resin composition according to any one of (1) to (5), further comprising 5 to 200 parts by mass of a fibrous reinforcing material (F).
(7) The semi-aromatic polyamide resin composition according to (6), wherein the fibrous reinforcing material (F) is glass fiber and / or carbon fiber.
(8) The semi-aromatic polyamide resin composition according to any one of (1) to (7), further comprising a polyamide other than the semi-aromatic polyamide (A).
(9) A molded article obtained by molding the semi-aromatic polyamide resin composition according to any one of the above (1) to (8).

  According to the present invention, there is provided a semi-aromatic polyamide resin composition in which thermal aging in a temperature atmosphere of about 100 to 160 ° C. is highly suppressed and there is no concern about deterioration in physical properties in an environment in this temperature range. be able to.

Hereinafter, the present invention will be described in detail.
The semi-aromatic polyamide resin composition of the present invention contains a semi-aromatic polyamide (A), a copper compound (B), an alkali metal halide compound (C), and a polyhydric alcohol (D).

  The semi-aromatic polyamide (A) constituting the semi-aromatic polyamide resin composition of the present invention contains an aromatic dicarboxylic acid component and an aliphatic diamine component as constituent components. The semi-aromatic polyamide (A) may contain a copolymer component. However, from the viewpoints of heat resistance, mechanical strength, chemical resistance, rapid crystallization, and a low-temperature mold, a molded product can be obtained. In other words, it preferably comprises a single aromatic dicarboxylic acid component and a single aliphatic diamine component.

  In the present invention, examples of the aromatic dicarboxylic acid component constituting the semi-aromatic polyamide (A) include terephthalic acid, phthalic acid, isophthalic acid, and naphthalenedicarboxylic acid. Above all, terephthalic acid is preferable since heat resistance can be improved.

  Acid components to be copolymerized in addition to the aromatic dicarboxylic acid component include oxalic acid, malonic acid, succinic acid, glutaric acid, adipic acid, pimelic acid, suberic acid, azelaic acid, sebacic acid, undecandioic acid, dodecanedioic acid, etc. And dicarboxylic acids such as alicyclic dicarboxylic acids such as cyclohexanedicarboxylic acid. The copolymerization amount of an aromatic dicarboxylic acid other than terephthalic acid, an aliphatic dicarboxylic acid, or an alicyclic dicarboxylic acid is determined based on the total number of moles of the raw material monomer in order not to lower the melting point and heat resistance of the semi-aromatic polyamide (A). On the other hand, it is preferably at most 5 mol%, more preferably substantially not contained.

  In the present invention, examples of the aliphatic diamine component constituting the semi-aromatic polyamide (A) include 1,2-ethanediamine, 1,3-propanediamine, 1,4-butanediamine, and 1,5-pentanediamine. 1,6-hexanediamine, 1,7-heptanediamine, 1,8-octanediamine, 1,9-nonanediamine, 1,10-decanediamine, 1,11-undecanediamine, 1,12-dodecanediamine, -Methyl-1,5-pentanediamine and 2-methyl-1,8-octanediamine. It is preferable to use one kind of the aliphatic diamine component alone, rather than to use a plurality of the above-mentioned kinds in combination, and to obtain a molded article having a good balance of heat resistance and mechanical properties and excellent in chemical resistance. Therefore, it is preferable to use 1,10-decanediamine alone.

  Examples of the diamine component to be copolymerized in addition to the aliphatic diamine component include an alicyclic diamine such as cyclohexanediamine and an aromatic diamine such as xylylenediamine and benzenediamine. The copolymerization amount of an alicyclic diamine or an aromatic diamine other than the aliphatic diamine component is not more than 5 mol% with respect to the total number of moles of the raw material monomers so as not to impair the above-mentioned properties provided by the aliphatic diamine component. Is preferable, and it is more preferable that it is not substantially contained.

  In the present invention, other copolymerization components constituting the semi-aromatic polyamide (A) include lactams such as caprolactam and laurolactam, and ω-aminocarboxylic acids such as aminocaproic acid and 11-aminoundecanoic acid. The amount of these copolymers is preferably 5 mol% or less based on the total number of moles of the raw material monomers, so as not to lower the heat resistance, mechanical properties and chemical resistance of the semi-aromatic polyamide (A). More preferably, it is not substantially contained.

  As described above, the semi-aromatic polyamide (A) in the present invention preferably comprises a single aromatic dicarboxylic acid component and a single aliphatic diamine component, but the semi-aromatic polyamide resin composition of the present invention May contain two or more semi-aromatic polyamides (A) having different constituent monomer components.

  In the present invention, the semi-aromatic polyamide (A) preferably contains a monocarboxylic acid component as a constituent component in order to enhance heat aging resistance, fluidity, and releasability. The content of the monocarboxylic acid component is preferably from 0.3 to 4.0 mol%, more preferably from 0.3 to 3.0 mol%, based on all monomer components constituting the semi-aromatic polyamide (A). More preferably, it is more preferably 0.3 to 2.5 mol%, and particularly preferably 0.8 to 2.5 mol%.

  The molecular weight of the monocarboxylic acid is preferably 140 or more, more preferably 170 or more. When the molecular weight of the monocarboxylic acid is 140 or more, the semi-aromatic polyamide (A) has further improved heat aging resistance, fluidity, and releasability. Further, by improving the fluidity at the time of melt processing, the processing temperature can be lowered, and thermal deterioration at the time of melt processing can be suppressed. As a result, heat aging resistance is also improved. In addition, when the resin composition contains a semi-aromatic polyamide (A) containing a monocarboxylic acid component having a molecular weight of 140 or more together with the polyhydric alcohol (D), the crystallization rate during molding remains unchanged. The resulting compact has an improved crystallinity. As a result, the chemical resistance of the molded body is synergistically improved. In the field of automobiles, molded articles such as parts that come into contact with antifreeze liquid are required to have chemical resistance, and are particularly useful for this purpose.

  Examples of the monocarboxylic acid component include aliphatic monocarboxylic acids, alicyclic monocarboxylic acids, and aromatic monocarboxylic acids, and aliphatic monocarboxylic acids are preferable from the viewpoint of fluidity and mold release properties.

Examples of the aliphatic monocarboxylic acid having a molecular weight of 140 or more include caprylic acid, nonanoic acid, decanoic acid, lauric acid, myristic acid, palmitic acid, stearic acid, and behenic acid. Among them, stearic acid is preferred because of its high versatility.
Examples of the alicyclic monocarboxylic acid having a molecular weight of 140 or more include 4-ethylcyclohexanecarboxylic acid, 4-hexylcyclohexanecarboxylic acid, and 4-laurylcyclohexanecarboxylic acid.
Examples of the aromatic monocarboxylic acid having a molecular weight of 140 or more include 4-ethylbenzoic acid, 4-hexylbenzoic acid, 4-laurylbenzoic acid, alkylbenzoic acids, 1-naphthoic acid, 2-naphthoic acid and the like. Derivatives.

  The monocarboxylic acid components may be used alone or in combination. Further, a monocarboxylic acid having a molecular weight of 140 or more and a monocarboxylic acid having a molecular weight of less than 140 may be used in combination. In the present invention, the molecular weight of the monocarboxylic acid indicates the molecular weight of the raw material monocarboxylic acid.

  In the present invention, the semi-aromatic polyamide (A) needs to have a melting point of 280 to 350 ° C, preferably 300 to 350 ° C, more preferably 305 to 340 ° C, and more preferably 310 to 350 ° C. More preferably, the temperature is 335 ° C. When the melting point of the semi-aromatic polyamide (A) is less than 280 ° C, the resulting semi-aromatic polyamide resin composition may have poor heat aging resistance due to insufficient crystallinity. On the other hand, when the melting point of the semi-aromatic polyamide (A) exceeds 350 ° C., the decomposition temperature of the polyamide bond is about 350 ° C., so that the carbonization or decomposition proceeds during melt processing. In the present invention, the melting point is defined as the top of the endothermic peak when the temperature is increased at a rate of temperature increase of 20 ° C./minute by a differential scanning calorimeter (DSC).

  In the present invention, the relative viscosity of the semi-aromatic polyamide (A) measured in 96% sulfuric acid at 25 ° C. at a concentration of 1 g / dL is preferably 1.8 or more from the viewpoint of mechanical properties. , Preferably 1.8 to 3.5, more preferably 2.2 to 3.1. If the semi-aromatic polyamide (A) has a relative viscosity of more than 3.5, melt processing may be difficult.

  The method for producing the semi-aromatic polyamide (A) is not particularly limited, but a conventionally known heat polymerization method or solution polymerization method can be used. Among them, a heat polymerization method is preferably used because it is industrially advantageous. Examples of the heat polymerization method include a method comprising a step (i) of obtaining a reaction product from an aromatic dicarboxylic acid component and an aliphatic diamine component, and a step (ii) of polymerizing the obtained reaction product. .

  In the step (i), for example, the aromatic dicarboxylic acid powder is previously heated to a temperature equal to or higher than the melting point of the aliphatic diamine and equal to or lower than the melting point of the aromatic dicarboxylic acid. In order to maintain the state of the dicarboxylic acid powder, there is a method of adding an aliphatic diamine substantially without containing water. Alternatively, as another method, a suspension composed of an aliphatic diamine in a molten state and a solid aromatic dicarboxylic acid is stirred and mixed to obtain a mixed solution, and then the melting point of a semi-aromatic polyamide finally formed is obtained. At a temperature of less than, a method of producing a salt by the reaction of an aromatic dicarboxylic acid and an aliphatic diamine and a reaction of producing a low polymer by polymerization of the produced salt to obtain a mixture of a salt and a low polymer. Can be In this case, the crushing may be performed while the reaction is being performed, or the crushing may be performed after the reaction is once taken out. In the step (i), the former in which the shape of the reaction product can be easily controlled is preferable.

  In the step (ii), for example, the reaction product obtained in the step (i) is subjected to solid-state polymerization at a temperature lower than the melting point of the semi-aromatic polyamide to be finally formed, to thereby 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 an 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 the steps (i) and (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 different apparatuses.

  The heating method in the heat polymerization method is not particularly limited, but includes a method of heating the reaction vessel with a medium such as water, steam, or a heat medium oil, a method of heating the reaction vessel with an electric heater, and stirring generated by stirring. A method utilizing frictional heat accompanying the motion of the contents such as heat is exemplified. Further, these methods may be combined.

  In the production of the semi-aromatic polyamide (A), a polymerization catalyst may be used to increase the efficiency of polymerization. Examples of the polymerization catalyst include phosphoric acid, phosphorous acid, hypophosphorous acid, and salts thereof. Usually, the addition amount of the polymerization catalyst is preferably 2 mol% or less based on all monomer components constituting the semi-aromatic polyamide (A).

The semi-aromatic polyamide resin composition of the present invention contains a copper compound (B).
Examples of the copper compound (B) used in the present invention include cuprous chloride, cupric chloride, cuprous bromide, cupric bromide, cuprous iodide, copper acetate, copper propionate, and benzoic acid. Examples thereof include copper oxide, copper adipate, copper terephthalate, copper isophthalate, copper sulfate, copper phosphate, copper borate, copper nitrate, copper stearate, and a copper complex salt coordinated with a chelating agent. Among them, copper halide is preferred, and cuprous iodide and cuprous bromide are more preferred. The copper compound (B) may be used alone or in combination.

  The content of the copper compound (B) must be 0.01 to 2 parts by mass, and is 0.02 to 0.5 parts by mass, based on 100 parts by mass of the semi-aromatic polyamide (A). Is preferred. When the content of the copper compound (B) is less than 0.01 parts by mass, the effect of improving the heat aging resistance of the resin composition is not seen. On the other hand, when the content of the copper compound (B) exceeds 2 parts by mass, the effect is saturated and not only is it economically disadvantageous, but also the obtained molded product may be colored and impair the appearance.

The semi-aromatic polyamide resin composition of the present invention contains an alkali metal halide (C).
Examples of the alkali metal halide compound (C) used in the present invention include potassium iodide, potassium bromide, potassium chloride, sodium iodide, sodium bromide, and sodium chloride. Among them, potassium iodide, bromide Potassium is preferred. The alkali metal halide (C) may be used alone or in combination.

  The content of the alkali metal halide compound (C) needs to be 0.1 to 5 parts by mass with respect to 100 parts by mass of the semi-aromatic polyamide (A), and is 0.2 to 3 parts by mass. Preferably, there is. When the content of the alkali metal halide compound (C) is less than 0.1 part by mass, the resin composition does not show the effect of improving the heat aging resistance. On the other hand, when the content of the alkali metal halide compound (C) exceeds 3 parts by mass, the effect is saturated, which is not only economically disadvantageous but also may make the resin composition brittle.

  In the present invention, the mass ratio (B / C) of the copper compound (B) and the alkali metal halide compound (C) is from 1/2 to 1/20 from the viewpoint of improving mechanical strength and heat aging resistance. Preferably, there is.

The semi-aromatic polyamide resin composition of the present invention contains a polyhydric alcohol (D).
The polyhydric alcohol (D) used in the present invention is a compound containing two or more hydroxyl groups. Examples of the polyhydric alcohol (D) include a saturated aliphatic compound, an unsaturated aliphatic compound, an alicyclic compound, an aromatic compound, and a saccharide. The polyhydric alcohol may contain one or more heteroatoms, such as oxygen, nitrogen and / or sulfur. The polyhydric alcohol (D) may contain a substituent other than a hydroxyl group, for example, an ether, carboxylic acid, amide or ester group. Further, the polyhydric alcohol may be a low molecular weight compound or a polymer type high molecular weight compound in which certain monomer units are repeated. As the polyhydric alcohol (D), one type may be used alone, or two or more types may be used in combination.
The semi-aromatic polyamide resin composition of the present invention has improved heat aging resistance by containing the polyhydric alcohol (D). Further, since the semi-aromatic polyamide resin composition of the present invention contains polyhydric alcohol (D) and has improved fluidity, it is possible to lower the processing temperature during melt processing, Thermal degradation during melt processing can be suppressed.

  Examples of the saturated aliphatic compound include ethylene glycol, diethylene glycol, triethylene glycol, 1,4-butanediol, 1,5-pentanediol, 2,2-dimethyl-1,3-propanediol, and glycerin monomethacrylate. Glycerol, trimethylolpropane, hexane-1,2,6-triol, 1,1,1-tris- (hydroxymethyl) ethane, 3- (2'-hydroxyethoxy) -propane-1, 2-diol, 3- (2'-hydroxypropoxy) -propane-1,2-diol, 2- (2'-hydroxyethoxy) -hexane-1,2-diol, 6- (2'-hydroxypropoxy)- Hexane-1,2-diol, 1,1,1-tris-[(2'-hydroxyeth C) -Methyl] -ethane, 1,1,1-tris-[(2'-hydroxypropoxy) -methyl] -propane, di-trimethylolpropane, trimethylolpropane ethoxylate, trimethylolpropanepropoxylate, etc. Trivalent low molecular weight alcohols such as pentaerythritol, dipentaerythritol, and tripentaerythritol; polyethylene glycol, polyglycerin, polyvinyl alcohol, ethylene-vinyl alcohol copolymer resin, polyvinyl butyral (for example, Kuraray Co., Ltd.) Mowital, hydroxyl-terminated polybutadiene at both ends (eg, GI series manufactured by Nippon Soda Co., Ltd.), hydroxyl-terminated polybutadiene at both ends (eg, G series manufactured by Nippon Soda Co., Ltd.), dendritic polyalcohol (eg, par Tope Co. Boltorn), polycaprolactone polyols (e.g., Daicel Co. PLACCEL 200 series, 300 series, and a high molecular weight polyhydric alcohol 400 series) and the like.

Examples of the unsaturated aliphatic compound include ricinoleyl alcohol.
Examples of the alicyclic compound include 1,2-cyclohexanediol, 1,3-cyclohexanediol, 1,4-cyclohexanediol, 1,3,5-cyclohexanetriol, and 2,3-di- (2′-hydroxy Ethyl) -cyclohexane-1-ol.
Examples of the aromatic compound include 1,2-benzenedimethanol, 1,3-benzenedimethanol, 1,4-benzenedimethanol, hydrobenzoin, 1,1,2,2-tetraphenylethane-1,2. -Diol, 1,1,1-tris- (4'-hydroxyphenyl) -ethane, 1,1,1-tris- (hydroxyphenyl) -propane, 1,1,3-tris- (dihydroxy-3-methyl Phenyl) -propane, 1,1,4-tris- (dihydroxyphenyl) -butane, 1,1,5-tris- (hydroxyphenyl) -3-methylpentane, and bisphenoxyethanolfluorene.
Examples of the saccharide include cyclodextrin, D-mannose, glucose, galactose, sucrose, fructose, xylose, arabinose, D-mannitol, D-sorbitol, D- or L-arabitol, xylitol, iditol, galactitol, talitol, Allitol, altitol, gilitol, erythritol, threitol, ribitol, D-gulonic acid-γ-lactone.

  Examples of the polyhydric alcohol having two or more hydroxyl groups and having an ester group as another substituent include esters composed of pentaerythritol and a fatty acid (for example, Unistar H series manufactured by NOF Corporation) and dipentaerythritol. Polyhydric alcohols that are ester-bonded to a fatty acid while leaving two or more hydroxyl groups, such as an ester composed of a dibasic acid (for example, Pren Riser series manufactured by Ajinomoto Fine Techno Co., Ltd.) are exemplified.

  The content of the polyhydric alcohol (D) must be 0.05 to 10 parts by mass, and is 0.1 to 8 parts by mass with respect to 100 parts by mass of the semi-aromatic polyamide (A). , And more preferably 0.2 to 6 parts by mass. When the content of the polyhydric alcohol (D) is less than 0.05 parts by mass, the resin composition has no effect of suppressing heat aging. On the other hand, when the mass amount of the polyhydric alcohol (D) exceeds 10 parts by mass, the effect of suppressing heat aging is saturated, and not only no further effect can be expected, but also the resin composition becomes polyvalent during melt processing. Alcohol vaporizes and generates a large amount of gas, retention stability is poor, and molded products have poor appearance due to polyhydric alcohol bleeding out on the surface and insufficient mechanical properties It may be.

The semi-aromatic polyamide resin composition of the present invention preferably further contains talc (E). The semi-aromatic polyamide resin composition of the present invention, by containing talc, has not only an effect of improving heat aging resistance, but also an effect of improving chemical resistance and hydrolysis resistance, and an effect of improving mechanical strength. can get. Specifically, there are effects such as an improvement in the retention of mechanical properties when exposed to a high temperature for a long time in a liquid such as an automobile oil or an automobile coolant.
The talc (E) may be subjected to a surface treatment in order to neutralize, reduce the coagulation action, and improve the wettability with the semi-aromatic polyamide (A). Examples of the surface treating agent include organic acids such as epoxy-based, amino-based, silicon-based, and fatty acid-based.
The form of the talc (E) is not particularly limited, and examples thereof include a plate, a scale, a scale, and a flake.
The average particle size of the talc (E) is preferably 0.5 to 60 μm, and more preferably 0.5 to 20 μm. When talc has an average particle size of less than 0.5 μm, agglomerates are likely to be generated due to poor dispersion, and the obtained molded product may not be uniform and may have poor mechanical properties. On the other hand, when the average particle size of talc exceeds 60 μm, the surface of the molded product may be rough.
Talc (E) may be used alone or in combination of two or more.
The content of talc (E) is preferably from 0.1 to 100 parts by mass, more preferably from 0.1 to 50 parts by mass, based on 100 parts by mass of the semi-aromatic polyamide (A). More preferably, the amount is 0.5 to 20 parts by mass. When the content of talc (E) is less than 0.1 part by mass, the effect of improving the heat aging resistance may not be obtained. On the other hand, when the content of talc (E) is more than 100 parts by mass, the effect is not only saturated, but also the obtained molded body may be reduced in mechanical strength.

  The semi-aromatic polyamide resin composition of the present invention preferably further contains a fibrous reinforcing material (F). The fibrous reinforcing material (F) is not particularly limited, but includes, for example, glass fiber, carbon fiber, boron fiber, polyvinyl alcohol fiber, polyester fiber, acrylic fiber, wholly aromatic polyamide fiber, polybenzoxazole fiber, and polytetrafluorocarbon. Examples include ethylene 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 fibers and carbon fibers are preferred because they have a high effect of improving mechanical properties, have heat resistance enough to withstand the heating temperature during melt-kneading with a semi-aromatic polyamide resin, and are easily available. As the fibrous reinforcing material (F), one type may be used alone, or two or more types may be used in combination.

The fibrous reinforcing material (F) such as glass fiber and carbon fiber is preferably treated with a surface treatment agent such as a sizing agent. The main component of the sizing agent is preferably a coupling agent or a film forming agent.
Examples of the coupling agent include vinylsilane-based, acrylsilane-based, epoxysilane-based, aminosilane-based, and aminotitanium-based coupling agents. Among them, aminosilane-based coupling agents are preferred because they have a high adhesion effect between the semi-aromatic polyamide (A) and the glass fiber or carbon fiber and have excellent heat resistance.
Examples of the film-forming agent include urethane-based, epoxy-based, and acrylic-based resins. Among them, a urethane-based resin is preferable because of its high adhesion effect to glass fibers or carbon fibers and excellent heat resistance. The film forming agent preferably contains an acid component because the hydrolysis resistance of the resin composition is improved. The acid component is preferably copolymerized with a resin which is a main component of the film forming agent. Examples of the acid component include unsaturated monocarboxylic acids such as acrylic acid, methacrylic acid, and cinnamic acid; unsaturated dicarboxylic acids such as maleic acid, fumaric acid, and itaconic acid; and maleic anhydride.

  The fiber length and fiber diameter of the fibrous reinforcing material (F) are not particularly limited, but the fiber length is preferably 0.1 to 7 mm, and more preferably 0.5 to 6 mm. When the fiber length of the fibrous reinforcing material (F) is 0.1 to 7 mm, the resin composition can be reinforced without adversely affecting the moldability. The fiber diameter of the fibrous reinforcing material (F) is preferably from 3 to 20 μm, more preferably from 5 to 14 μm. When the fiber diameter of the fibrous reinforcing material (F) is 3 to 20 μm, the resin composition can be reinforced without breaking during melt-kneading. Examples of the cross-sectional shape of the fibrous reinforcing material (F) include a circle, a rectangle, an ellipse, and other irregular cross-sections. Among them, a circle is preferable.

  When the fibrous reinforcing material (F) is used, its content is preferably from 5 to 200 parts by mass, more preferably from 10 to 180 parts by mass, per 100 parts by mass of the semi-aromatic polyamide (A). The content is more preferably 20 to 150 parts by mass, and particularly preferably 30 to 130 parts by mass. When the content of the fibrous reinforcing material (F) is less than 5 parts by mass, the effect of improving the mechanical properties may be small. On the other hand, if the content exceeds 200 parts by mass, the effect of improving the mechanical properties is saturated, and not only the effect of improving the mechanical properties is not expected, but also the workability during melt-kneading is reduced, and the semi-aromatic polyamide resin composition It may be difficult to obtain product pellets. In addition, the fluidity during melt processing is greatly impaired, and the resin temperature increases due to shear heat, or the resin temperature must be increased to improve fluidity, resulting in a situation. In some cases, the molecular weight, mechanical properties, and heat aging resistance may be reduced.

  The semi-aromatic polyamide resin composition of the present invention can contain various stabilizers such as an antioxidant, a light stabilizer, and a heat stabilizer to further improve melt stability and effectively suppress heat aging. . Examples of the antioxidant include a hindered phenol-based antioxidant, a sulfur-based antioxidant, and a phosphorus-based antioxidant, and examples of the light stabilizer include a hindered amine-based light stabilizer. Above all, a phosphorus-based antioxidant is preferable for suppressing heat aging, and a hindered phenol-based antioxidant and a hindered amine-based light stabilizer are preferable for improving retention stability. When various stabilizers are used, the content is preferably 0.01 to 2.0 parts by mass, preferably 0.05 to 1.0 part by mass, per 100 parts by mass of the semi-aromatic polyamide (A). More preferably, there is.

Examples of the hindered phenolic antioxidant include, for example, n-octadecyl-3- (3 ', 5'-di-t-butyl-4'-hydroxyphenyl) -propionate, n-octadecyl-3- (3'- Methyl-5'-t-butyl-4'-hydroxyphenyl) -propionate, n-tetradecyl-3- (3 ', 5'-di-t-butyl-4'-hydroxyphenyl) -propionate, 1,6- Hexanediol-bis- [3- (3,5-di-t-butyl-4-hydroxyphenyl) -propionate], 1,4-butanediol-bis- [3- (3,5-di-t-butyl) -4-hydroxyphenyl) -propionate], 2,2'-methylenebis- (4-methyl-t-butylphenol), triethylene glycol-bis- [3- (3-t-bu 5-methyl-4-hydroxyphenyl) -propionate], tetrakis [methylene-3- (3 ', 5'-di-tert-butyl-4'-hydroxyphenyl) propionate] methane, 3,9-bis [ 2- {3- (3-t-butyl-4-hydroxy-5-methylphenyl) propionyloxy} -1,1-dimethylethyl] 2,4,8,10-tetraoxaspiro [5.5] undecane; N, N'-bis-3- (3 ', 5'-di-tert-butyl-4'-hydroxyphenyl) propionylhexamethylenediamine, N, N'-tetramethylene-bis-3- (3'-methyl -5'-tert-butyl-4'-hydroxyphenol) propionyldiamine, N, N'-bis- [3- (3,5-di-tert-butyl-4-hydroxyphenol) propioni Hydrazine, N-salicyloyl-N'-salicylidenehydrazine, 3- (N-salicyloyl) amino-1,2,4-triazole, N, N'-bis [2- {3- (3,5-di -Tert-butyl-4-hydroxyphenyl) propionyloxydiethyl! Oxyamide, pentaerythrityl-tetrakis [3- (3,5-di-tert-butyl-4-hydroxyphenyl) propionate], N, N'-hexa Methylene bis- (3,5-di-t-butyl-4-hydroxy-hydrocinnamide is mentioned.
Among them, triethylene glycol-bis- [3- (3-t-butyl-5-methyl-4-hydroxyphenyl) -propionate], tetrakis [methylene-3- (3 ', 5'-di-t-butyl- 4'-hydroxyphenyl) propionate] methane, 1,6-hexanediol-bis- [3- (3,5-di-tert-butyl-4-hydroxyphenyl) -propionate], pentaerythrityl-tetrakis [3- (3,5-di-t-butyl-4-hydroxyphenyl) propionate] and N, N'-hexamethylenebis- (3,5-di-t-butyl-4-hydroxy-hydrocinnamide are preferred. Hinder The dophenolic antioxidants may be used alone or in combination.
Commercially available hindered phenolic antioxidants include, for example, Adeka's ADK STAB AO-20, AO-30, AO-40, AO-50, AO-60, AO-70, AO-80, AO-330, Irganox 245, 259, 565, 1010, 1035, 1076, 1098, 1222, 1330, 1425, 1520, 3114, 5057 manufactured by Ciba Specialty Chemical Co., Ltd., Sumitomo Chemical Co., Ltd. Sumilizer BHT-R, MDP-S, BBM-S , WX-R, NW, BP-76, BP-101, GA-80, GM, GS, and Cyanox CY-1790 manufactured by Cyanamid.

  Examples of the sulfur-based antioxidants include distearyl 3,3'-thiodipropionate, pentaerythrityltetrakis (3-laurylthiopropionate), 2-mercaptobenzimidazole, didodecyl 3,3'-thiodipro Pionate, dioctadecyl 3,3'-thiodipropionate, ditridecyl 3,4'-thiodipropionate, 2,2-bis [[3- (dodecylthio) -1-oxopropoxy] methyl] -1,3 -Propanediyl esters. Among them, distearyl 3,3'-thiodipropionate and pentaerythrityltetrakis (3-laurylthiopropionate) are preferred. The sulfur-based antioxidants may be used alone or in combination. Examples of commercially available sulfur-based antioxidants include Sumilizer Chemical Industries Ltd. Sumilizer TP-D and MB.

  The phosphorus antioxidant may be either an inorganic compound or an organic compound. Examples of the phosphorus antioxidant include inorganic phosphates such as monosodium phosphate, disodium phosphate, trisodium phosphate, sodium phosphite, calcium phosphite, magnesium phosphite, and manganese phosphite; Phenyl phosphite, trioctadecyl phosphite, tridecyl phosphite, trinonyl phenyl phosphite, diphenyl isodecyl phosphite, bis (2,6-di-tert-butyl-4-methylphenyl) pentaerythritol diphosphite, bis (2,4-di-tert-butylphenyl) pentaerythritol diphosphite, tris (2,4-di-tert-butylphenyl) phosphite, distearylpentaerythritol diphosphite, bis (nonylphenyl) pentaerythritol diphosphite Phosph , 1,1'-biphenyl-4,4'-diylbis [bis (2,4-di-tert-butylphenyl) phosphonite], tetrakis (2,4-di-tert-butylphenyl) 4,4 Organophosphorus compounds such as' -biphenylene-di-phosphonite, tetra (tridecyl-4,4'-isopropylidenediphenyldiphosphite, 2,2-methylenebis (4,6-di-tert-butylphenyl) octyl phosphite) The phosphorus-based antioxidants may be used alone or in combination.Examples of commercially available phosphorus-based antioxidants include ADK STAB PEP-8, PEP-36, and PEP- manufactured by Adeka Corporation. 4C, PEP-24G, and Hostanox P-EPQ manufactured by Clariant Japan.

  Examples of hindered amine light stabilizers include tetrakis (1,2,2,6,6-pentamethyl-4-piperidyl) butane-1,2,3,4-tetracarboxylate and tetrakis (2,2,6,6- Tetramethyl-1-piperidyl) butane-1,2,3,4-tetracarboxylate, dimethyl succinate-1- (2-hydroxyethyl) -4-hydroxy-2,2,6,6-tetramethyl- 4-piperidine polycondensate, bis (1,2,2,6,6-pentamethyl-4-piperidyl) sebacate, poly [(6-morpholino-S-triazine-2,4-diyl) [2,2 6,6-tetramethyl-4-piperidyl] imino] -hexamethylene [(2,2,6,6-tetramethyl-4-piperidyl) imino]. The hindered amine light stabilizers may be used alone or in combination. Commercially available stabilizers include, for example, Nylostab S-EED manufactured by Clariant Japan, Biosorb 04 manufactured by Kyodo Yakuhin, Cyasorb UV-3346 manufactured by Cytec, and Adeka Stab LA-57, LA-63P, LA-68 manufactured by Adeka. Timasorb 119, 944 and Tinuvin 622, 765 manufactured by the company.

  The content of the stabilizer is preferably from 0.005 to 3 parts by mass, more preferably from 0.1 to 2 parts by mass, per 100 parts by mass of the semi-aromatic polyamide (A).

The semi-aromatic polyamide resin composition of the present invention may contain a polyamide other than the semi-aromatic polyamide (A).
The polyamide other than the semi-aromatic polyamide (A) (hereinafter, may be abbreviated as “other polyamide”) is not particularly limited, but it is amorphous or semi-aromatic having a melting point of less than 300 ° C. Polyamide and aliphatic polyamide are mentioned.

  Examples of the semi-aromatic polyamide other than the semi-aromatic polyamide (A) include a copolymer of terephthalic acid, isophthalic acid, and aliphatic diamine.

  Examples of the aliphatic polyamide other than the semi-aromatic polyamide (A) include polyamide 6, polyamide 11, polyamide 12, polyamide 46, polyamide 410, polyamide 412, polyamide 510, polyamide 512, polyamide 66, polyamide 610, and polyamide 610. 612, polyamide 1010, polyamide 1012, polyamide 6/66, polyamide 66/1010, polyamide 66/612, polyamide 2Me5C, polyamide 6C, polyamide 8C, polyamide 9C, polyamide 10C, and polyamide 12C. Note that C represents 1,4-cyclohexanedicarboxylic acid, and 2Me5 represents 2-methylpentamethylenediamine.

  When the semi-aromatic polyamide resin composition contains another polyamide, its content is preferably from 1 to 100 parts by mass, preferably from 3 to 80 parts by mass, per 100 parts by mass of the semi-aromatic polyamide (A). And more preferably 3 to 50 parts by mass. By containing other polyamides in an amount of 1 to 100 parts by mass, the semi-aromatic polyamide resin composition of the present invention has improved flowability during melt processing, thereby improving moldability, and the surface appearance of the obtained molded article Also improve. Furthermore, since it is possible to lower the temperature of the melt processing due to the high fluidity, it is possible to improve the heat aging resistance by lowering the melt processing temperature and suppressing heat deterioration during the melt processing. it can. If the content is less than 1 part by mass, the above effect may not be obtained. On the other hand, if the content exceeds 100 parts by mass, the heat resistance and mechanical properties of the semi-aromatic polyamide (A) may be impaired.

  The semi-aromatic polyamide resin composition of the present invention may further contain other additives such as a filler, a colorant, and an antistatic agent, if necessary. Examples of the filler include a swellable clay mineral, silica, alumina, glass beads, and graphite. Examples of the coloring agent include pigments such as titanium oxide and carbon black, and dyes such as nigrosine. In particular, by containing nigrosine, the fluidity of the semi-aromatic polyamide resin composition during melt processing is improved, and the melt processing temperature can be reduced, and the heat aging resistance can be improved. The appearance is improved.

In the present invention, a semi-aromatic polyamide (A), a copper compound (B), an alkali metal halide compound (C), a polyhydric alcohol (D), and talc (E) added as needed, fibrous reinforcement The method for producing the semi-aromatic polyamide resin composition of the present invention by mixing the material (F) and other additives is not particularly limited, but a melt-kneading method is preferred.
Examples of the melt kneading method include a method using a batch type kneader such as Brabender, a Banbury mixer, a Henschel mixer, a helical rotor, a roll, a single screw extruder, a twin screw extruder, or the like. The melt-kneading temperature is not particularly limited as long as the semi-aromatic polyamide (A) melts and does not decompose. However, if it is too high, the semi-aromatic polyamide (A) decomposes. (Melting point −20 ° C.) or more and (melting point of semi-aromatic polyamide + 40 ° C.) or less.

  The molten resin composition is extruded into a strand shape to form a pellet, hot cut or underwater cut into a pellet shape, extruded into a sheet and cut, or extruded into a block and pulverized It can be processed into various shapes by, for example, a method of forming into a powder shape.

  The molded article of the present invention is obtained by molding the above semi-aromatic polyamide resin composition. Examples of the molding method include an injection molding method, an extrusion molding method, a blow molding method, and a sintering molding method. The injection molding method is preferable because the mechanical properties and moldability are greatly improved.

  The injection molding machine is not particularly limited, and examples thereof include a screw in-line type injection molding machine and a plunger type injection molding machine. The semi-aromatic polyamide resin composition heated and melted in the cylinder of the injection molding machine is weighed for each shot, injected into a mold in a molten state, cooled in a predetermined shape, and solidified. Removed from the mold. The resin temperature at the time of injection molding is more preferably (melting point of semi-aromatic polyamide−20 ° C.) or more and less than (melting point of semi-aromatic polyamide + 40 ° C.). Since the resin composition of the present invention has excellent fluidity during melt processing, it is not necessary to increase the resin temperature during molding more than necessary. Therefore, the resin temperature at the time of molding can be lowered, and the thermal degradation at the time of melt processing can be reduced.

  When the semi-aromatic polyamide resin composition is melt-processed, it is preferable to use sufficiently dried semi-aromatic polyamide resin composition pellets. When a semi-aromatic polyamide resin composition containing a large amount of water is used, the resin foams in a cylinder of an injection molding machine, and it may be difficult to obtain an optimal molded product. The water content of the semi-aromatic polyamide resin composition pellets used for injection molding is preferably less than 0.3 part by mass, based on 100 parts by mass of the semi-aromatic polyamide resin composition, and less than 0.1 part by mass. More preferably, there is.

The semi-aromatic polyamide resin composition of the present invention can be used as a molded article molding resin for a wide range of uses such as automobile parts, electric and electronic parts, miscellaneous goods, industrial equipment parts, civil engineering and construction supplies.
Automotive parts include, for example, thermostat members, IGBT module members for inverters, actuator members, insulators, motor insulators, radiator members, radiator hoses, various valves, exhaust finishers, power device housings, ECU housings, motor members, coil members. , Resolver member, cable covering material, vehicle camera housing, vehicle camera lens holder, vehicle connector, engine mount, intercooler, bearing retainer, oil seal ring, chain cover, ball joint, chain tensioner, clutch member, torsion Seat, starter gear, reducer gear, internal gear, in-vehicle lithium-ion battery tray, in-vehicle high-voltage fuse housing, in-vehicle electric circuit Housing of the sectional device, turbocharger impellers and the like for automobiles.
Examples of electrical and electronic components include connectors, ECU connectors, main ten-lock connectors, modular jacks, reflectors, LED reflectors, switches, sensors, sockets, pin sockets, capacitors, jacks, fuse holders, relays, coil bobbins, breakers, and circuits. Parts, electromagnetic switches, holders, covers, plugs, housing parts for electric and electronic devices such as portable personal computers and word processors, impellers, vacuum cleaner impellers, resistors, variable resistors, ICs, LED housings, camera housings Body, camera barrel, camera lens holder, tact switch, tact switch for lighting, curling iron cabinet, curling iron comb, small switch for all-mold DC, organic EL display switch, material for 3D printer, bond magnet for motor Materials.
Miscellaneous goods include, for example, trays, sheets, and binding bands.
Industrial equipment parts include, for example, insulators, connectors, gears, switches, washers, bearing retainers, sensors, impellers, and plarail chains.
Examples of civil engineering and construction supplies include fences, storage boxes, construction switchboards, anchor bolt guides, anchor rivets, solar cell panel raising materials, and brake pads for wind power generation.
Since the semi-aromatic polyamide resin composition of the present invention has a highly suppressed thermal aging in an atmosphere at a temperature of about 100 ° C. to 160 ° C., it is used for a long time in a high temperature environment. It can be used particularly preferably for molded articles of

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

1. Measurement method The physical properties of the semi-aromatic polyamide and the semi-aromatic polyamide resin composition were measured by the following methods.
(1) Melting point Using a differential scanning calorimeter DSC-7 type (manufactured by PerkinElmer), the temperature was raised to 360 ° C at a rate of 20 ° C / min in a nitrogen atmosphere, and the temperature was maintained at 360 ° C for 5 minutes, and the temperature was lowered. The temperature was lowered to 25 ° C. at a rate of 20 ° C./min, and further maintained at 25 ° C. for 5 minutes. The top of the endothermic peak when the temperature was measured again at a rate of 20 ° C./min was taken as the melting point.

(2) Relative viscosity The measurement was performed at 25 ° C. at a concentration of 1 g / dL using 96% by mass of sulfuric acid as a solvent.

(3) Tensile strength, heat aging (tensile strength retention)
Using the test pieces 1 to 4 produced by the following method, the tensile strength was measured in accordance with ISO178. The tensile strength retention (%) of each of the test pieces 2, 3, and 4 with respect to the test piece 1 was determined, and the heat aging resistance at 150 ° C, 170 ° C, and 190 ° C was evaluated.
<Test piece 1> (Test piece prepared under standard conditions)
The semi-aromatic polyamide resin composition was subjected to cylinder temperature (melting point of semi-aromatic polyamide + 15 ° C.) and mold temperature (melting point of semi-aromatic polyamide-175 using an injection molding machine S2000i-100B (manufactured by FANUC). C), and injection molding was performed under the conditions of a residence time in the cylinder of 10 seconds, to produce a test piece 1 (ISO multipurpose test piece).
<Test piece 2> (Test piece for heat aging evaluation, heat treatment at 150 ° C x 3000 hours)
The test piece 1 was heat-treated at 150 ° C. for 3000 hours in a hot blast stove under an air atmosphere to prepare a test piece 2.
<Test piece 3> (Test piece for heat aging evaluation, heat treatment at 170 ° C for 3000 hours)
The test piece 1 was heat-treated at 170 ° C. for 3000 hours in a hot-blast furnace in an air atmosphere to prepare a test piece 3.
<Test piece 4> (Test piece for heat aging evaluation, heat treatment at 190 ° C. for 3000 hours)
The test piece 1 was heat-treated at 190 ° C. for 3000 hours in a hot blast stove under an air atmosphere to prepare a test piece 4.

(4) Fluidity (melt flow rate)
In accordance with JIS K7210, the temperature was measured at the melting point of the semi-aromatic polyamide + 20 ° C. under a load of 1.2 kgf.

(5) Surface appearance The surface appearance of the test piece 1 was visually observed and evaluated according to the following criteria.
：: There is no floating of the fibrous reinforcing material, and there is no roughness on the surface.
：: Either floating or rough or both.
X: Coloring, bleed-out, or both.

(6) Hydrolysis resistance (tensile strength retention)
The test piece 1 was immersed in an autoclave at 130 ° C. in a hot air oven at a temperature of 130 ° C. in a pressure vessel, immersed in an aqueous solution obtained by diluting a vehicle coolant Long Life Coolant (LLC) (Toyota genuine “Super Long Life Coolant”) twice with pure water. The test piece 5 was produced by heat treatment for 1000 hours. The tensile strength retention (%) of the test piece 5 with respect to the test piece 1 was determined, and the hydrolysis resistance was evaluated.

2. Raw Materials Raw materials used in Examples and Comparative Examples are shown below.
(1) Aromatic dicarboxylic acid component • TPA: terephthalic acid (2) Aliphatic diamine component • DDA: 1,10-decanediamine • NDA: 1,9-nonanediamine (3) Monocarboxylic acid • STA: Stearic acid (molecular weight) : 284)
-BA: benzoic acid (molecular weight: 122)

(4) Copper compound (B)
B-1: Copper iodide (special grade reagent)
(5) An alkali metal halide compound (C)
C-1: Potassium iodide (special grade reagent)
・ C-2: Potassium bromide (special grade reagent)
(6) Polyhydric alcohol (D)
-D-1: dipentaerythritol (PerPent, DiPenta90)
-D-2: ester composed of dipentaerythritol and adipic acid (Pren riser ST-210, manufactured by Ajinomoto Fine Techno Co.)

(7) Talc (E)
E-1: manufactured by Nippon Talc, MS-ZC, average particle size 11 μm, surface-treated product E-2: manufactured by Nippon Talc, SG-2000, average particle size 1 μm
E-3: manufactured by Nippon Talc, MS-KY, average particle size 25 μm
(8) Fibrous reinforcement (F)
F-1: glass fiber (ECS03T-262H, manufactured by NEC Corporation, average fiber diameter 10.5 μm, average fiber length 3 mm, using a film-forming agent containing an acid copolymer)
F-2: glass fiber (manufactured by NEC Corporation, ECS03T-289DE, average fiber diameter 6 μm, average fiber length 3 mm)
-F-3: carbon fiber (Toho Tenax Co., Ltd., HTA-C6-NR, average fiber diameter 7 m, average fiber length 6 mm)

(9) Polyamides other than semi-aromatic polyamide (A) P-1: Polyamide 6T / 6I (manufactured by Ms. Chemie Japan, Grivory G21, amorphous)
P-2: Polyamide 6 (A1030BRT, crystalline, manufactured by Unitika Ltd.)
(10) Stabilizer / AO-1: bis (2,6-di-tert-butyl-4-methylphenyl) pentaerythritol diphosphite (phosphorus antioxidant, ADEKA CORPORATION, ADEKA STAB PEP-36)
AO-2: 3,9-bis [2- {3- (3-t-butyl-4-hydroxy-5-methylphenyl) propionyloxy} -1,1-dimethylethyl] 2,4,8,10 -Tetraoxaspiro [5.5] undecane (hindered phenolic antioxidant, manufactured by ADEKA, ADK STAB AO-80)

(11) Production of semi-aromatic polyamide / semi-aromatic polyamide (A-1)
4.70 kg of powdery terephthalic acid (TPA) as an aromatic dicarboxylic acid component, 0.32 kg of stearic acid (STA) as a monocarboxylic acid component, and 9.3 g of sodium hypophosphite monohydrate as a polymerization catalyst. Was placed in a ribbon blender-type reactor and heated to 170 ° C. while stirring at a rotation speed of 30 rpm under a nitrogen atmosphere. Thereafter, while maintaining the temperature at 170 ° C. and the rotation speed at 30 rpm, 4.98 kg of 1,10-decanediamine (DDA) heated to 100 ° C. as an aliphatic diamine component was added using a liquid injection device. For 2.5 hours to obtain a reaction product. The molar ratio of the starting monomers was TPA: DDA: STA = 48.5: 49.6: 1.9 (the equivalent ratio of the functional groups of the starting monomers was TPA: DDA: STA = 49.0: 50.0). : 1.0).
Subsequently, the obtained reaction product was heated and polymerized in the same reactor at 250 ° C. and a rotation speed of 30 rpm for 8 hours under a nitrogen stream to produce a semi-aromatic polyamide powder.
Thereafter, the obtained semi-aromatic polyamide powder is formed into strands using a twin-screw kneader, and the strands are cooled and solidified by passing through a water tank, and then cut with a pelletizer to obtain semi-aromatic polyamide (A-1). A pellet was obtained.

・ Semi-aromatic polyamides (A-2) to (A-5)
Semi-aromatic polyamides (A-2) to (A-5) were obtained in the same manner as the semi-aromatic polyamide (A-1) except that the resin composition was changed as shown in Table 1.

  Table 1 shows the resin composition and characteristic values of the obtained semi-aromatic polyamide.

Example 1
100 parts by mass of semi-aromatic polyamide (A-1), 0.1 part by mass of copper compound (B-1), 1 part by mass of alkali metal halide compound (C-1), 1 part by mass of polyhydric alcohol (D-1) Parts are dry-blended and weighed using a loss-in-weight continuous continuous feeding device CE-W-1 (manufactured by Kubota Corporation), and a screw diameter 26 mm, L / D50, co-axial twin screw extruder TEM26SS (Toshiba Machine Co., Ltd.) (Manufactured by K.K.) and melt-kneaded. On the way, 45 parts by mass of the fibrous reinforcing material (F-1) was supplied from a side feeder, and kneading was further performed. After the strand was taken out from the die in a strand shape, it was cooled and solidified by passing through a water tank, and cut with a pelletizer to obtain pellets of a semi-aromatic polyamide resin composition. The barrel temperature setting of the extruder was (melting point of semi-aromatic polyamide + 5 ° C.) to (melting point of semi-aromatic polyamide + 15 ° C.), screw rotation speed 250 rpm, and discharge rate 25 kg / h.

Examples 2-31, Comparative Examples 1-5
Except that the composition of the semi-aromatic polyamide resin composition was changed as shown in Table 2, the same operation as in Example 1 was performed to obtain a semi-aromatic polyamide resin composition pellet.

  Various evaluation tests were performed using the obtained semi-aromatic polyamide resin composition pellets. Table 2 shows the results.

Since the resin compositions of Examples 1 to 31 satisfy the requirements of the present invention, thermal aging under a 150 ° C. temperature atmosphere is highly suppressed, and the tensile strength retention after 3000 hours has passed is 95%. % Or more. Also, the surface appearance was excellent.
In Example 2, since the monocarboxylic acid component of the semi-aromatic polyamide resin was an aliphatic monocarboxylic acid, the fluidity during melt processing was lower than that of Example 3 in which the monocarboxylic acid component was an aromatic monocarboxylic acid. The character was excellent.
In Example 2, since the aliphatic diamine component of the semi-aromatic polyamide resin was 1,10-decanediamine, the tensile strength was higher than that of Example 4 in which the aliphatic diamine component was 1,9-nonanediamine. Was.
In Examples 2 and 4, since the semi-aromatic polyamide resin was a homo-type, the crystallinity was higher and the tensile strength retention after 3000 hours had passed was higher than that of Example 5 of the copolymerization type.
In Examples 2 and 6 to 15, as the content of the copper compound, the alkali metal halide, and the polyhydric alcohol increases, the heat aging of the resin composition is suppressed, but the effect is saturated in a high concentration region. I was Also, the higher the content of polyhydric alcohol, the lower its tensile strength.
In Examples 16 to 22, the talc-containing resin composition had a higher tensile strength retention after 3000 hours and a higher tensile strength retention after immersion in the LLC liquid as compared to Example 2. In Examples 16 to 18 and 20, the resin composition containing the fibrous reinforcing material had improved crystallinity and high tensile strength by containing talc.
In Examples 26 and 27, the resin composition containing a glass fiber or a carbon fiber having a small fiber diameter had higher tensile strength than that of Example 2.
In Examples 28 to 30, the resin compositions containing other polyamides were superior in surface appearance as compared with Example 2.
In Example 31, the resin composition containing the stabilizer had a higher tensile strength retention after 3000 hours than in Example 2.
Example 2 in which a copper compound and an alkali metal halide compound and a polyhydric alcohol were used in combination, Comparative Example 2 in which only a copper compound and an alkali metal halide compound were used, and Comparative Example 3 in which only a polyhydric alcohol was used. By comparing the heat treatment temperature and the heat aging resistance of Comparative Example 1 in which no copper compound and an alkali metal halide compound were used at a heat treatment temperature as low as about 150 ° C., although the heat aging effect was small, It has been found that the effect of heat aging resistance is remarkably improved by using a polyhydric alcohol and a polyhydric alcohol together for unknown reasons.

Since the resin compositions of Comparative Examples 1 to 3 did not contain any of the copper compound, the alkali metal halide compound, and the polyhydric alcohol, the heat aging was large and the tensile strength retention was low.
Since the resin composition of Comparative Example 4 had a large content of the copper compound and the alkali metal halide compound, the obtained pellets and molded articles were strongly colored and had poor appearance.
Since the resin composition of Comparative Example 5 had a large content of polyhydric alcohol, a large amount of polyhydric alcohol gas was generated during melt processing. In addition, the obtained molded article was not only low in mechanical strength but also inferior in appearance due to polyhydric alcohol bleeding out on the surface.

Claims (9)

  100 parts by mass of a semi-aromatic polyamide (A) containing an aromatic dicarboxylic acid component and an aliphatic diamine component and having a melting point of 280 to 350 ° C, 0.01 to 2 parts by mass of a copper compound (B), an alkali halide A semi-aromatic polyamide resin composition comprising 0.1 to 5 parts by mass of a metal compound (C) and 0.05 to 10 parts by mass of a polyhydric alcohol (D).   2. The semi-aromatic polyamide resin composition according to claim 1, wherein the tensile strength retention after 3000 hours at 150 ° C. in an air atmosphere is 95% or more.   The semi-aromatic polyamide resin composition according to claim 1 or 2, further comprising 0.1 to 100 parts by mass of talc (E).   The semi-aromatic polyamide (A) contains a monocarboxylic acid component, and the content is 0.3 to 4.0 mol% with respect to all monomer components constituting the semi-aromatic polyamide (A). The semi-aromatic polyamide resin composition according to claim 1, wherein:   The semi-aromatic polyamide resin composition according to any one of claims 1 to 4, wherein the polyhydric alcohol (D) is dipentaerythritol or a derivative thereof.   The semi-aromatic polyamide resin composition according to any one of claims 1 to 5, further comprising 5 to 200 parts by mass of a fibrous reinforcing material (F).   The semi-aromatic polyamide resin composition according to claim 6, wherein the fibrous reinforcing material (F) is glass fiber and / or carbon fiber.   The semi-aromatic polyamide resin composition according to any one of claims 1 to 7, further comprising a polyamide other than the semi-aromatic polyamide (A). A molded article obtained by molding the semi-aromatic polyamide resin composition according to any one of claims 1 to 8.