JP2013227555A - Polyamide resin composition for automobile engine room interior part - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a polyamide resin composition that has low water absorptivity, and that is extremely suitable for an automobile engine room interior part excellent in dimensional stability between under a room temperature and high temperature environment.SOLUTION: A polyamide resin composition includes at least 0.01 pt.wt. and at most 200 pts.wt. of an inorganic filler based on 100 pts.wt. of a polyamide resin obtained by performing polycondensation of a monomer containing an aliphatic dicarboxylic acid of at least 7 of a carbon number as a major component with tetramethylenediamine. The polyamide resin composition for an automobile engine room interior part is such that a ratio of a storage modulus at 110°C measured by a bending mode to a storage modulus at 30°C measured by a bending mode (storage modulus 110°C/storage modulus at 30°C) is at least 0.30, and a value of a peak top of tanδ that corresponds to a glass transition temperature of the polyamide resin is at most 0.098.

Description

  The present invention relates to a polyamide for parts in an automobile engine room, in which an inorganic filler is blended with a polyamide resin obtained by polycondensation of monomers mainly composed of tetramethylenediamine and an aliphatic dicarboxylic acid having 7 or more carbon atoms. The present invention relates to a resin composition.

  Polyamide resins represented by nylon 66 have excellent heat resistance, oil resistance, and toughness, and have been used in various functional parts such as automobile engine compartment parts. As environmental awareness is increasing on a global scale, demands for reducing the environmental impact of automobile manufacturers are becoming strict, and various efforts to reduce the environmental impact, such as measures to improve fuel consumption, noise, and exhaust gas, are being carried out. Yes. In measures to improve fuel efficiency, heat sources are diversified by adopting new systems such as hybrid systems. As a countermeasure against noise, the engine room is hermetically sealed by installing a large under cover. Furthermore, in the exhaust gas countermeasure, the exhaust pipe temperature rises due to the addition of the catalyst. Thus, the required characteristics of the polyamide resin used in a high temperature environment (100 ° C. or higher) in the engine room are becoming increasingly severe. The polyamide resin has a characteristic of easily absorbing water due to the presence of a hydrophilic amide group. However, particularly when used in a high temperature environment, there is a concern that the molded product may bulge due to evaporation of water absorbed in the molded piece. It was required to be low. Moreover, the resin composition for parts in an automobile engine room has been required to have a property of not easily deforming even in a high temperature environment.

  As aliphatic polyamide resins other than nylon 66, nylon 610 (for example, see Patent Document 1) and nylon 46 (for example, see Patent Document 2) are known. Nylon 610 has a lower water absorption than nylon 66 and is superior in dimensional stability at room temperature, but has insufficient dimensional stability between room temperature and high temperature environment, and is used in the high temperature environment as described above. There was still room for improvement in the engine compartment. Nylon 46 is excellent in mechanical properties and dimensional stability between room temperature and high temperature environment, but because of its high water absorption, there is a concern that blistering may occur due to water evaporation in a high temperature environment of 100 ° C. or higher. Inferior blister properties has been a problem.

  On the other hand, a polyamide resin composed of a monomer composed of tetramethylenediamine and an aliphatic dicarboxylic acid having 8 to 14 carbon atoms is also known (see, for example, Patent Documents 3 to 4). And excellent mechanical properties.

JP 2010-31210 A JP-A-56-149431 International Publication No. 2000/09586 International Publication No. 2010/098335

  However, the properties in a high temperature environment of a polyamide resin composed of a monomer composed of tetramethylenediamine and an aliphatic dicarboxylic acid having 8 to 14 carbon atoms have not been known. Further, it has not been known that the dimensional stability is remarkably improved when an inorganic filler is blended. An object of the present invention is to provide a polyamide resin composition that has low water absorption and is extremely suitable for parts in an automobile engine room that is excellent in dimensional stability between room temperature and high temperature.

  The present inventors provide a polyamide resin composition obtained by blending an inorganic filler with a polyamide resin obtained by polycondensation of monomers mainly composed of tetramethylenediamine and an aliphatic dicarboxylic acid having 7 or more carbon atoms. In addition, because of its excellent low water absorption and high temperature rigidity, it has excellent dimensional stability between room temperature and high temperature environment. Therefore, such a resin composition is particularly suitable for automobile engine room parts used under high temperature environment. As a result, the present invention has been completed.

That is, the present invention
(1) 0.01 parts by weight or more of an inorganic filler with respect to 100 parts by weight of a polyamide resin obtained by polycondensation of monomers mainly composed of tetramethylenediamine and an aliphatic dicarboxylic acid having 7 or more carbon atoms 200 parts by weight or less of a polyamide resin composition, which is a ratio of storage elastic modulus at 110 ° C. measured in bending mode to storage elastic modulus at 30 ° C. measured in bending mode (storage elastic modulus at 110 ° C. / Polyamide resin composition for automotive engine compartment parts, wherein the storage elastic modulus at 30 ° C.) is 0.30 or more, and the peak top value of tan δ corresponding to the glass transition temperature of the polyamide resin is 0.098 or less,
(2) The polyamide resin composition for automotive engine compartment components according to (1), wherein the inorganic filler includes a non-fibrous inorganic filler,
(3) The non-fibrous inorganic filler is at least one selected from the group consisting of talc, wollastonite, mica and kaolin, and the polyamide resin composition for automotive engine room components according to (2),
(4) The polyamide resin composition for automotive engine compartment components according to (2) or (3), wherein the inorganic filler further contains a fibrous inorganic filler,
(5) The polyamide resin composition for automotive engine compartment components according to (4), wherein the fibrous inorganic filler is glass fiber and / or carbon fiber,
(6) The polyamide resin composition for automotive engine compartment parts according to any one of (1) to (5), wherein the saturated water absorption is 6.0% by weight or less,
(7) The aliphatic dicarboxylic acid having 7 or more carbon atoms is at least one selected from the group consisting of azelaic acid, sebacic acid, undecanedioic acid and dodecanedioic acid, according to any one of (1) to (6) The polyamide resin composition for automotive engine compartment parts as described,
(8) An automotive engine compartment part formed by molding the polyamide resin composition according to any one of (1) to (7).

  According to the polyamide resin composition for automobile engine compartment parts of the present invention, it is possible to provide an automobile engine compartment part having low water absorption and excellent dimensional stability between room temperature and high temperature.

  Hereinafter, the present invention will be described in detail.

  The polyamide resin composition for automotive engine compartment parts according to the present invention comprises a polyamide resin obtained by polycondensation of monomers mainly composed of tetramethylenediamine and an aliphatic dicarboxylic acid having 7 or more carbon atoms. . Here, “the main component is tetramethylenediamine and an aliphatic dicarboxylic acid having 7 or more carbon atoms” means that the total weight of tetramethylenediamine and the aliphatic dicarboxylic acid having 7 or more carbon atoms is a raw material. Of 70% by weight or more. More preferably, it is 80 weight% or more, More preferably, it is 90 weight% or more.

  Examples of the dicarboxylic acid having 7 or more carbon atoms used in the present invention include pimelic acid, suberic acid, azelaic acid, sebacic acid, undecanedioic acid, dodecanedioic acid, tridecanedioic acid, tetradecanedioic acid, pentadecanedioic acid, and hexadecanedioic acid. Examples include acid, heptadecanedioic acid, octadecanedioic acid, 1,2-cyclohexanedicarboxylic acid, 1,3-cyclohexanedicarboxylic acid, 1,4-cyclohexanedicarboxylic acid, and the like. In particular, azelaic acid, sebacic acid, undecanedioic acid and dodecanedioic acid, which are excellent in the balance between low water absorption and high-temperature rigidity, are preferred, and sebacic acid is most preferred.

  The polyamide resin used in the present invention can copolymerize at least one component other than tetramethylenediamine and an aliphatic dicarboxylic acid having 7 or more carbon atoms in a range of less than 30% by weight of the total components. is there. More preferably, it is less than 20 weight%, More preferably, it is less than 10 weight%. Examples of the component to be copolymerized include ethylenediamine, 1,3-diaminopropane, 1,5-diaminopentane, 1,6-diaminohexane, 1,7-diaminoheptane, 1,8-diaminooctane, 1,9- Diaminononane, 1,10-diaminodecane, 1,11-diaminoundecane, 1,12-diaminododecane, 1,13-diaminotridecane, 1,14-diaminotetradecane, 1,15-diaminopentadecane, 1,16-diamino Hexadecane, 1,17-diaminoheptadecane, 1,18-diaminooctadecane, 1,19-diaminononadecane, 1,20-diaminoeicosane, 2-methyl-1,5-diaminopentane, 2-methyl-1, Aliphatic diamines such as 8-diaminooctane, cyclohexanediamine, bis- ( -Aminocyclohexyl) alicyclic diamines such as methane, aromatic diamines such as xylylenediamine, alicyclics such as oxalic acid, malonic acid, succinic acid, glutaric acid, adipic acid and the like, and cyclohexanedicarboxylic acid. Aromatic dicarboxylic acids such as dicarboxylic acid, phthalic acid, isophthalic acid, naphthalenedicarboxylic acid, amino acids such as 6-aminocaproic acid, 11-aminoundecanoic acid, 12-aminododecanoic acid, paraaminomethylbenzoic acid, ε-caprolactam, ω- Examples include lactam such as laurolactam.

  As a method for producing the polyamide resin used in the present invention, for example, tetramethylenediamine and an aliphatic dicarboxylic acid having 7 or more carbon atoms, or a salt thereof, and if necessary, other copolymer components are heated to synthesize a low-order condensate. Examples of the method include solid phase polymerization or a method for increasing the degree of melt polymerization through the step of performing the step. Take out the low-order condensate once, then perform solid-phase polymerization or melt polymerization in the same reaction vessel, followed by solid-phase polymerization or two-stage polymerization to increase the degree of melt polymerization with an extruder, etc. Either one-stage polymerization may be used. The polyamide resin obtained by melt polymerization has a narrow molecular weight distribution compared to the polyamide resin obtained by solid phase polymerization, and the content of relatively low molecular weight components is relatively small. It is more preferable because mechanical properties are improved. The low-order condensate is defined as a polyamide resin having a sulfuric acid relative viscosity described later of 1.05-1.90. Heat polycondensation is defined as a production process in which the maximum temperature of the polyamide resin during production is increased to 180 ° C. or higher. Solid-phase polymerization is a step of heating in a temperature range of 100 ° C. to a melting point under reduced pressure or in an inert gas, and melting high polymerization degree is a step of heating to a melting point or higher under normal pressure or reduced pressure. Show.

  When producing a polyamide resin, tetramethylene diamine and pyrrolidine produced by the cyclization reaction are volatilized or pyrrolidine becomes a terminal blocking agent. The total amino group amount with respect to the total carboxyl group amount decreases, and the polymerization rate tends to be delayed. In order to suppress the volatilization of tetramethylenediamine, it is preferable that the pressure in the polymerization system is high. However, when the volatilization of condensed water is suppressed, the cyclization reaction of tetramethylenediamine tends to be promoted. Therefore, in the present invention, it is preferable that the maximum pressure in the polymerization system is 0.1 to 2.5 MPa. More preferably, it is 0.2-2.0 MPa, More preferably, it is 0.2-1.5 MPa, Most preferably, it is 0.25-1.0 MPa. By setting the pressure to 0.1 MPa or more and 2.5 MPa or less, the condensation reaction can be efficiently advanced while sufficiently suppressing the volatilization of tetramethylenediamine. As the condensation reaction proceeds, condensed water is generated and the pressure in the system rises, so the pressure at the start of polymerization may be zero, but in order to minimize the volatilization of tetramethylenediamine, The pressure in the system can be adjusted to be high by a method of adding water or a method of pressurizing with an inert gas in advance at the start of polymerization.

  In order to obtain a high-molecular weight polyamide resin, it is preferable to add a specific amount of tetramethylenediamine in advance at the stage of charging the raw material to adjust the amount of amino groups in the polymerization system. When the number of moles of tetramethylenediamine used as a raw material is A and the number of moles of a dicarboxylic acid having 7 or more carbon atoms is B, the raw material composition ratio is set so that the ratio A / B is 1.005 to 1.07. It is preferable to adjust, and it is more preferable to adjust a raw material composition ratio so that it may become 1.01-1.06. By setting A / B to 1.005 or more and less than 1.07, the equimolarity of tetramethylenediamine and dicarboxylic acid in the polymerization system can be appropriately maintained, and the degree of polymerization can be easily increased.

  In the heat polycondensation of polyamide resin, in addition to suppressing the volatilization of tetramethylenediamine and the suppression of cyclization due to deammonia reaction, in order to prevent coloring, it is necessary to minimize the thermal history received by the polymer throughout the polymerization process. Preferably, it is effective to lower the maximum temperature reached in the polymerization system as the means. In the present invention, when the low-order condensate is melted and highly polymerized, the highest temperature reached in the polymerization system is preferably not less than the melting point of the polyamide resin and not more than 300 ° C., more preferably not less than the melting point and the melting point. + 40 ° C. or lower. By setting the maximum temperature to be at least the melting point and not more than 300 ° C., the volatilization and cyclization of tetramethylenediamine can be efficiently suppressed, and a polyamide resin with high whiteness can be obtained. In the case of increasing the degree of polymerization in the solid phase, it is preferable to perform solid phase polymerization at a melting point of −40 ° C. or higher and lower than the melting point under reduced pressure or in an inert gas atmosphere.

  The degree of polymerization of the polyamide resin is preferably such that the relative viscosity at 25 ° C. of a 98% sulfuric acid solution of 0.01 g / ml is 2.0 to 5.0. More preferably, it is 2.2-4.5, More preferably, it is 2.3-4.0. By setting the relative viscosity to 2.0 to 5.0, a polyamide resin having both toughness and moldability can be obtained.

  In the heat polycondensation of the polyamide resin, a polymerization accelerator can be added as necessary. As the polymerization accelerator, for example, phosphoric acid, phosphorous acid, hypophosphorous acid, pyrophosphoric acid, polyphosphoric acid and inorganic phosphorus compounds such as alkali metal salts and alkaline earth metal salts thereof are preferable. Sodium acid and sodium hypophosphite are preferably used. The polymerization accelerator is preferably used in the range of 0.001 to 1 part by weight with respect to 100 parts by weight of the raw material. By setting the addition amount of the polymerization accelerator to 0.001 to 1 part by weight, a polyamide resin having a polymerization degree excellent in melt processability can be obtained in a short polymerization time.

  The automobile engine room in which the polyamide resin composition is used in the present invention may be exposed to a high temperature of 100 ° C. or higher due to radiation from the engine, transmission, heat due to stagnation, heat of outside air transmitted through the hood, and the like. Polyamide resins having a hydrophilic amide group in the molecular structure are required to further reduce water absorption because the moisture absorbed in the air atmosphere may evaporate in a high temperature environment and the molded product may swell. It was done. Further, since the temperature reaches a temperature higher than the glass transition temperature of the aliphatic polyamide resin in a high temperature environment, there is a concern of deformation, and thus a property that is difficult to deform in a high temperature environment has been required. Therefore, in the present invention, the suppression of deformation under a high temperature environment is examined, the high temperature rigidity of the resin composition is focused, and the storage elastic modulus at 110 ° C. measured in the bending mode as an index of the high temperature rigidity, the bending The ratio with the storage elastic modulus at 30 ° C. measured in the mode (hereinafter referred to as “storage elastic modulus at 110 ° C./storage elastic modulus at 30 ° C.”) will be noted. Here, the storage elastic modulus at 30 ° C. was assumed assuming steady conditions, and the storage elastic modulus at 110 ° C. was assumed as an index assuming the temperature in the engine room. The polyamide resin composition for automobile engine compartment parts of the present invention needs to have a storage elastic modulus at 110 ° C./a storage elastic modulus at 30 ° C. of 0.30 or more. When the storage elastic modulus at 110 ° C./the storage elastic modulus at 30 ° C. is less than 0.30, the change in the storage elastic modulus at 30 to 110 ° C. increases and the dimensional change at 30 to 110 ° C. also increases. 0.40 or more is preferable and 0.51 or more is more preferable. In addition, although there is no prescription | regulation of the storage elastic modulus in 110 degreeC / the storage elastic modulus in 30 degreeC, when making the compounding quantity of an inorganic filler into the range suitable for a shaping | molding process, it tends to become 0.80 or less. Here, a storage elastic modulus can be calculated | required by shape | molding an Izod test piece of width 13mm and thickness 3mm, and measuring dynamic viscoelasticity in the temperature range of frequency 1Hz and 20 to 200 degreeC. The polyamide resin composition for automobile engine compartment parts according to the present invention has a large storage elastic modulus at 110 ° C. relative to a storage elastic modulus at 30 ° C. Therefore, this polyamide resin or a polyamide resin composition formed by blending this polyamide resin The parts in the automobile engine room formed by molding have a feature that the dimensional change at 30 to 110 ° C. is small. A polyamide resin composition having such an elastic modulus ratio is, for example, an inorganic filler in a polyamide resin obtained by polycondensation of a monomer mainly composed of tetramethylenediamine and an aliphatic dicarboxylic acid having 7 or more carbon atoms. It can be obtained by blending materials.

  Here, the storage elastic modulus at 30 ° C. is preferably 2.5 GPa or more, and the storage elastic modulus at 110 ° C. is preferably 0.78 GPa or more. By setting the storage elastic modulus within this range, it is possible to obtain a part in an automobile engine room having higher temperature rigidity and improved dimensional stability between room temperature and high temperature environment. More preferably, the storage elastic modulus at 30 ° C. is 3.0 GPa or more, more preferably 4.0 GPa or more, and most preferably 5.0 GPa or more. On the other hand, the storage elastic modulus at 110 ° C. is more preferably 0.90 GPa or more, further preferably 2.0 GPa or more, and most preferably 3.0 GPa or more. The polyamide resin composition having such an elastic modulus is, for example, an inorganic filler added to a polyamide resin obtained by polycondensation of a monomer mainly composed of tetramethylenediamine and an aliphatic dicarboxylic acid having 7 or more carbon atoms. It can obtain by mix | blending.

  In the present invention, the peak top value of tan δ corresponding to the glass transition temperature of the polyamide resin observed by the dynamic viscoelasticity measurement, which is an index of the mobility of the amorphous part, is 0.098 or less. It is necessary. When the peak top value of tan δ exceeds 0.098, the elastic modulus in a high temperature environment decreases due to the movement of the amorphous part, and the dimensional stability between room temperature and high temperature environment decreases. Preferably, it is 0.095 or less, more preferably 0.050 or less, and most preferably 0.040 or less. As a means for setting the peak top value of tan δ to 0.098 or less, for example, a high temperature obtained by polycondensation of a monomer mainly composed of tetramethylenediamine and an aliphatic dicarboxylic acid having 7 or more carbon atoms is used. Examples thereof include a method of blending an inorganic filler with a polyamide resin having excellent rigidity. Here, the value of the peak top of tan δ can be obtained by molding an Izod test piece having a width of 13 mm and a thickness of 3 mm, and measuring the dynamic viscoelasticity in a temperature range of 1 Hz and 20 ° C. to 200 ° C. .

  The polyamide resin composition used in the present invention preferably has a saturated water absorption of 6.0% by weight or less. More preferably, it is 5.0 weight% or less, More preferably, it is 4.0 weight% or less, Most preferably, it is 3.0 weight% or less. The saturated water absorption can be calculated from the change in weight before and after a 100 mm × 150 mm × 3 mm thick square plate was left in an atmosphere of 60 ° C. and 95% relative humidity for 500 hours. Polyamide resins absorb water during actual use due to the presence of hydrophilic amide groups, but by making the saturated water absorption not more than 6.0% by weight, the deformation of parts due to water evaporation in a high temperature environment can be further improved. Can be suppressed. Examples of means for setting the saturated water absorption to 6.0% by weight or less include using a dicarboxylic acid having 7 or more carbon atoms as a raw material for the polyamide resin.

  The polyamide resin composition for automotive engine compartment components according to the present invention is formed by blending 0.01 to 200 parts by weight of an inorganic filler with respect to 100 parts by weight of the polyamide resin. By blending an inorganic filler, the storage elastic modulus at 110 ° C./storage elastic modulus at 30 ° C. is increased due to its nucleating agent effect, amorphous part restraining effect, small deformation amount even under high temperature environment, etc. The dimensional stability between a room temperature and a high temperature environment of a molded product obtained from the resin composition can be improved.

  The compounding quantity of an inorganic filler needs to be 0.01-200 weight part with respect to 100 weight part of polyamide resins. If the blending amount of the inorganic filler is less than 0.01 parts by weight, the nucleating agent effect, the amorphous part constraining effect, and the effect of small deformation under a high temperature environment are not sufficiently achieved, and the effect of improving the high temperature rigidity is obtained. It becomes small and inferior in dimensional stability between room temperature and high temperature environment. 1.0 part by weight or more is preferable, 10 parts by weight or more is more preferable, 25 parts by weight is further preferable, and 40 parts by weight or more is most preferable. On the other hand, when the blending amount of the inorganic filler exceeds 200 parts by weight, the molding process becomes difficult. 150 parts by weight or less is preferable, and 120 parts by weight or less is more preferable.

  Examples of inorganic fillers include fibrous inorganic fillers and non-fibrous inorganic fillers. Two or more of these may be blended.

  When a fibrous inorganic filler is blended as the inorganic filler, the blending amount is preferably 190 parts by weight or less. By setting the blending amount of the fibrous inorganic filler to 190 parts by weight or less, the moldability of the polyamide resin composition can be further improved. 150 parts by weight or less is more preferable, and 100 parts by weight or less is more preferable.

  When a non-fibrous inorganic filler is blended as the inorganic filler, the blending amount is preferably 10 parts by weight or less. By setting the blending amount of the non-fibrous inorganic filler to 10 parts by weight or less, the toughness of a molded product obtained from the polyamide resin composition can be improved. 5 parts by weight or less is more preferable.

  Examples of the fibrous inorganic filler include glass fiber, carbon fiber, potassium titanate whisker, zinc oxide whisker, calcium carbonate whisker, wollastonite whisker, aluminum borate whisker, aramid fiber, alumina fiber, silicon carbide fiber, ceramic fiber, asbestos Examples thereof include fiber, gypsum fiber, and metal fiber. These may be hollow. Two or more of these may be blended. By blending the fibrous inorganic filler, the elastic modulus and rigidity of the molded product obtained from the polyamide resin composition can be improved.

  In order to improve the mechanical strength of the components in the automobile engine room, glass fibers and carbon fibers are particularly preferable among the fibrous inorganic fillers, and the storage elastic modulus at 110 ° C. can be further improved. The type of glass fiber is not particularly limited as long as it is generally used for reinforcing a resin, and can be selected from, for example, a long fiber type, a short fiber type chopped strand, a milled fiber, or the like. Further, the cross section of the glass fiber is not limited to a circular, flat gourd, eyebrows, oval, ellipse, rectangle or the like, but the warp peculiar to glass fiber compounded polyamide is not limited. In order to reduce it, the flat fiber preferably has a major axis / minor axis ratio of 1.5 to 10, more preferably 2.0 to 6.0. By setting the ratio of major axis / minor axis to 1.5 to 10, warpage can be reduced and excellent moldability can be imparted. The glass fiber may be coated or bundled with a thermoplastic resin such as an ethylene / vinyl acetate copolymer or a thermosetting resin such as an epoxy resin.

  Also, the type of carbon fiber is not particularly limited, and carbon fibers and graphite fibers produced using various known carbon fibers such as polyacrylonitrile (PAN), pitch, rayon, lignin, hydrocarbon gas, etc. Alternatively, fibers obtained by coating these fibers with metal can be used. Of these, PAN-based carbon fibers capable of improving mechanical properties can be preferably used. The carbon fiber usually has a shape such as a chopped strand, a roving strand, or a milled fiber cut to a predetermined length, and generally has a diameter of 15 μm or less, preferably 5 to 10 μm. When using chopped strands, the fiber length is not particularly limited, but it is preferable to use a strand having a high extrusion kneading workability. When using a roving strand, it can be combined by a known technique in which the roving strand is directly fed into an extruder. In the present invention, it is preferable to use chopped strands, and the number of filaments of carbon fiber strands, which are precursors of chopped carbon fibers, is preferably 1,000 to 150,000 from the viewpoint of manufacturing cost and stability in the production process.

  Non-fibrous inorganic fillers include, for example, talc, wollastonite, zeolite, sericite, mica, kaolin, clay, pyrophyllite, bentonite, asbestos, alumina silicate, non-swelling silicates such as calcium silicate, Li type Fluorine teniolite, Na-type fluorine teniolite, Na-type tetrasilicon fluorine mica, swellable layered silicate represented by the swellable mica of Li-type tetrasilicon fluorine mica, silicon oxide, magnesium oxide, alumina, silica, diatomaceous earth, zirconium oxide , Metal oxides such as titanium oxide, iron oxide, zinc oxide, calcium oxide, tin oxide, antimony oxide, carbonates such as calcium carbonate, magnesium carbonate, zinc carbonate, barium carbonate, dolomite, hydrotalcite, calcium sulfate, sulfuric acid Sulfate such as barium, hydroxide mug Smectite clay minerals such as hydroxides such as sium, calcium hydroxide, aluminum hydroxide and basic magnesium carbonate, montmorillonite, beidellite, nontronite, saponite, hectorite, and soconite, vermiculite, halloysite, kanemite, kenyanite, phosphoric acid Examples include various clay minerals such as zirconium and titanium phosphate, glass beads, glass flakes, ceramic beads, boron nitride, aluminum nitride, silicon carbide, calcium phosphate, carbon black, and graphite. The swellable layered silicate may be a swellable layered silicate in which exchangeable cations existing between layers are exchanged with organic onium ions, and examples of organic onium ions include ammonium ions, phosphonium ions, sulfonium ions, and the like. Can be mentioned. These non-fibrous inorganic fillers can be used in combination of two or more.

  In order to improve the surface appearance of the engine room components and improve the crystallization speed, the average particle diameter of the non-fibrous inorganic filler is preferably 0.001 to 10 μm. By setting the average particle size to 0.001 to 10 μm, it is possible to obtain a polyamide resin composition having excellent molding processability and a molded product surface appearance. The average particle diameter is preferably 0.01 to 5 μm, more preferably 0.05 to 3 μm. In addition, these average particle diameters are defined as D50 calculated | required by the cumulative particle size distribution curve measured by the laser diffraction method. In order to achieve both the reinforcement of the polyamide resin and the good surface appearance, it is preferable to use talc, kaolin, wollastonite, or swellable layered silicate as the non-fibrous inorganic filler.

  Furthermore, in the present invention, it is preferable to use a fibrous inorganic filler and a non-fibrous inorganic filler in combination, and the reinforcing effect that the fibrous inorganic filler has and the amorphous part restraining effect that the non-fibrous inorganic filler has. Due to synergistic expression, the mechanical properties and dimensional stability can be further improved.

  In addition, the inorganic filler is preferably pretreated with a coupling agent such as an isocyanate compound, an organic silane compound, an organic titanate compound, an organic borane compound, or an epoxy compound, thereby obtaining better mechanical strength. be able to. As the coupling agent, an organosilane compound is preferable, and specific examples thereof include γ-glycidoxypropyltrimethoxysilane, γ-glycidoxypropyltriethoxysilane, β- (3,4-epoxycyclohexyl) ethyl. Epoxy group-containing alkoxysilane compounds such as trimethoxysilane, γ-mercaptopropyltrimethoxysilane, mercapto group-containing alkoxysilane compounds such as γ-mercaptopropyltriethoxysilane, γ-ureidopropyltriethoxysilane, γ-ureidopropyltrimethoxy Silane, γ- (2-ureidoethyl) aminopropyltrimethoxysilane and other ureido group-containing alkoxysilane compounds, γ-isocyanatopropyltriethoxysilane, γ-isocyanatopropyltrimethoxysilane, γ-i Isocyanato group-containing alkoxysilanes such as socyanatopropylmethyldimethoxysilane, γ-isocyanatopropylmethyldiethoxysilane, γ-isocyanatopropylethyldimethoxysilane, γ-isocyanatopropylethyldiethoxysilane, and γ-isocyanatopropyltrichlorosilane Compounds, amino group-containing alkoxysilane compounds such as γ- (2-aminoethyl) aminopropylmethyldimethoxysilane, γ- (2-aminoethyl) aminopropyltrimethoxysilane, γ-aminopropyltrimethoxysilane, γ-hydroxypropyl Hydroxyl group-containing alkoxysilane compounds such as trimethoxysilane and γ-hydroxypropyltriethoxysilane, γ-methacryloxypropyltrimethoxysilane, vinyltrimethoxysilane, N-β- (N-vinylbenzylaminoethyl) -γ-aminopropyltrimethoxysilane / hydrocarbon-containing alkoxysilane compound such as hydrochloride, and acid anhydride group-containing alkoxysilane such as 3-trimethoxysilylpropylsuccinic anhydride Compound etc. are mentioned. In particular, γ-methacryloxypropyltrimethoxysilane, γ- (2-aminoethyl) aminopropylmethyldimethoxysilane, γ- (2-aminoethyl) aminopropyltrimethoxysilane, γ-aminopropyltrimethoxysilane, 3-tri Methoxysilylpropyl succinic anhydride is preferably used. For these silane coupling agents, a method in which an inorganic filler is surface-treated in advance according to a conventional method and then melt-kneaded with a polyamide resin is preferably used. However, the inorganic filler is not subjected to surface treatment of the inorganic filler in advance. A so-called integral blend method may be used in which these coupling agents are added when melt-kneading the polyamide resin.

  The treatment amount of these coupling agents is preferably 0.05 to 10 parts by weight with respect to 100 parts by weight of the inorganic filler. More preferably, it is 0.1-5 weight part, Most preferably, it is 0.5-3 weight part. By setting it as 0.05-10 weight part, it is excellent in the dispersibility to a polyamide resin, and can provide the high toughness improvement effect.

  In order to strengthen the interface between the polyamide resin and the inorganic filler, in addition to the treatment of the inorganic filler with a coupling agent, maleic anhydride, itaconic anhydride, glutaconic anhydride, citraconic anhydride, aconitic anhydride, or poly It is preferable to blend at least one anhydride selected from maleic anhydride. Among these, maleic anhydride and polymaleic anhydride are preferably used because of excellent balance between ductility and rigidity. As polymaleic anhydride, for example, those described in J. Macromol. Sci.-Revs. Macromol. Chem., C13 (2), 235 (1975) and the like can be used.

  The blending amount of these anhydrides is preferably 0.05 to 10 parts by weight with respect to 100 parts by weight of the polyamide resin from the viewpoint of improving ductility and the fluidity of the resulting composition, and further 0.1 to 5 parts by weight. The range is preferably 0.1 to 3 parts by weight, more preferably 0.1 to 1 part by weight.

  In addition, these anhydrides should just take the structure of an anhydride at the time of melt-kneading with a polyamide resin and an inorganic filler substantially, and hydrolyze and use for melt-kneading in the form of carboxylic acid or its aqueous solution, The dehydration reaction may be carried out by heating during melt kneading, and melt kneading with the polyamide resin in the form of substantially anhydrous acid may be used.

  The polyamide resin composition used in the present invention may further contain other types of polymers, impact resistance improvers, flame retardants, and the like, or two or more thereof.

  Examples of other types of polymers include other polyamides, polyethylene, polypropylene, polyester, polycarbonate, polyphenylene ether, polyphenylene sulfide, liquid crystal polymer, polysulfone, polyethersulfone, ABS resin, SAN resin, polystyrene, and the like. The blending amount of these other polymers is preferably 0.1 to 100 parts by weight with respect to 100 parts by weight of the polyamide resin obtained by polycondensation of tetramethylenediamine and an aliphatic dicarboxylic acid having 7 or more carbon atoms. . More preferably, it is 1 to 80 parts by weight, further preferably 3 to 50 parts by weight, and most preferably 5 to 40 parts by weight.

  In order to improve the impact resistance of the components in the engine room of the present invention, a modified polyolefin such as a (co) polymer obtained by polymerizing an olefin compound and / or a conjugated diene compound as an impact resistance improver. It is preferable to blend polyamide elastomer, polyester elastomer and the like. Two or more of these impact resistance improving materials can be used in combination.

  Examples of (co) polymers include ethylene copolymers, conjugated diene polymers, conjugated diene-aromatic vinyl hydrocarbon copolymers, and the like. Here, the ethylene-based copolymer means a copolymer of ethylene and another monomer and a multi-component copolymer, and the other monomer copolymerized with ethylene is an α having 3 or more carbon atoms. It can be selected from among olefins, non-conjugated dienes, vinyl acetate, vinyl alcohol, α, β-unsaturated carboxylic acids and derivatives thereof.

  As the α-olefin having 3 or more carbon atoms, for example, propylene and butene-1 can be preferably used. Examples of non-conjugated dienes include 5-methylidene-2-norbornene, 5-ethylidene-2-norbornene, dicyclopentadiene, 1,4-hexadiene, and the like. Examples of the α, β-unsaturated carboxylic acid include acrylic acid, methacrylic acid, ethacrylic acid, crotonic acid, maleic acid, fumaric acid, itaconic acid, citraconic acid, and butenedicarboxylic acid. Examples include esters, aryl esters, glycidyl esters, acid anhydrides, and imides.

  The conjugated diene polymer is a polymer having at least one conjugated diene as a constituent component. For example, a homopolymer such as 1,3-butadiene, 1,3-butadiene, and isoprene (2-methyl). -1,3-butadiene), 2,3-dimethyl-1,3-butadiene, and a copolymer of one or more monomers selected from 1,3-pentadiene. Those in which some or all of the unsaturated bonds of these polymers are reduced by hydrogenation can also be preferably used.

  The conjugated diene-aromatic vinyl hydrocarbon copolymer is a block copolymer or random copolymer comprising a conjugated diene and an aromatic vinyl hydrocarbon. In particular, 1,3-butadiene and isoprene are preferable. Examples of the aromatic vinyl hydrocarbon include styrene, α-methyl styrene, o-methyl styrene, p-methyl styrene, 1,3-dimethyl styrene, vinyl naphthalene, and among them, styrene is preferably used. In addition, a conjugated diene-aromatic vinyl hydrocarbon copolymer in which part or all of unsaturated bonds other than double bonds other than aromatic rings are reduced by hydrogenation can be preferably used.

  Specific examples of such impact resistance improvers include ethylene / propylene copolymer, ethylene / butene-1 copolymer, ethylene / hexene-1 copolymer, ethylene / propylene / dicyclopentadiene copolymer, Ethylene / propylene / 5-ethylidene-2-norbornene copolymer, unhydrogenated or hydrogenated styrene / isoprene / styrene triblock copolymer, unhydrogenated or hydrogenated styrene / butadiene / styrene triblock copolymer, ethylene / Methacrylic acid copolymers and some or all of the carboxylic acid moieties in these copolymers as salts with sodium, lithium, potassium, zinc, calcium, ethylene / methyl acrylate copolymers, ethylene / acrylic Ethyl acid copolymer, ethylene / methyl methacrylate copolymer, ethylene / methacrylic acid Ethyl acid copolymer, ethylene / ethyl acrylate-g-maleic anhydride copolymer (“g” represents graft, the same applies hereinafter), ethylene / methyl methacrylate-g-maleic anhydride copolymer, ethylene / Ethyl acrylate-g-maleimide copolymer, ethylene / ethyl acrylate-g-N-phenylmaleimide copolymer and partially saponified products of these copolymers, ethylene / glycidyl methacrylate copolymer, ethylene / vinyl acetate / Glycidyl methacrylate copolymer, ethylene / methyl methacrylate / glycidyl methacrylate copolymer, ethylene / glycidyl acrylate copolymer, ethylene / vinyl acetate / glycidyl acrylate copolymer, ethylene / glycidyl ether copolymer, ethylene / propylene-g -Anhydrous Inic acid copolymer, ethylene / butene-1-g-maleic anhydride copolymer, ethylene / propylene / 1,4-hexadiene-g-maleic anhydride copolymer, ethylene / propylene / dicyclopentadiene-g- Maleic anhydride copolymer, ethylene / propylene / 2,5-norbornadiene-g-maleic anhydride copolymer, ethylene / propylene-gN-phenylmaleimide copolymer, ethylene / butene-1-gN- Phenylmaleimide copolymer, hydrogenated styrene / butadiene / styrene-g-maleic anhydride copolymer, hydrogenated styrene / isoprene / styrene-g-maleic anhydride copolymer, ethylene / propylene-g-glycidyl methacrylate copolymer Polymer, ethylene / butene-1-g-glycidyl methacrylate copolymer, ethylene / propylene / 1,4-hexadiene-g-glycidyl methacrylate copolymer, ethylene / propylene / dicyclopentadiene-g-glycidyl methacrylate copolymer, hydrogenated styrene / butadiene / styrene-g-glycidyl methacrylate copolymer, Examples include nylon 12 / polytetramethylene glycol copolymer, nylon 12 / polytrimethylene glycol copolymer, polybutylene terephthalate / polytetramethylene glycol copolymer, polybutylene terephthalate / polytrimethylene glycol copolymer. it can. Among them, ethylene / methacrylic acid copolymers and some or all of the carboxylic acid moieties in these copolymers as salts with sodium, lithium, potassium, zinc, calcium, ethylene / propylene-g-anhydrous Maleic acid copolymers, ethylene / butene-1-g-maleic anhydride copolymers, hydrogenated styrene / butadiene / styrene-g-maleic anhydride copolymers are more preferable, ethylene / methacrylic acid copolymers and these A part or all of the carboxylic acid moiety in the copolymer made into a salt with sodium, lithium, potassium, zinc, calcium, ethylene / propylene-g-maleic anhydride copolymer, ethylene / butene-1-g -Maleic anhydride copolymers are particularly preferred.

  The blending amount of the impact resistance improving material is preferably 5 to 20 parts by weight with respect to 100 parts by weight of the polyamide resin. More preferably, it is 5 to 10 parts by weight. By setting it as 5-20 weight part, impact resistance can be provided, maintaining a high elasticity modulus.

  Examples of the flame retardant include non-halogen flame retardants that do not contain halogen atoms, such as phosphorus flame retardants, nitrogen flame retardants, and metal hydroxide flame retardants, and halogen flame retardants typified by bromine flame retardants. These flame retardants may be used in combination of two or more.

  The blending amount of the flame retardant is preferably 1 to 50 parts by weight with respect to 100 parts by weight of the polyamide resin. By setting it as 1-50 weight part, a flame retardance and toughness can be made compatible.

  Examples of the phosphorus-based flame retardant include polyphosphoric acid compounds such as red phosphorus, ammonium polyphosphate, and melamine polyphosphate, (di) phosphinic acid metal salts, phosphazene compounds, aromatic phosphate esters, aromatic condensed phosphate esters, And halogenated phosphoric acid esters.

  The (di) phosphinate is produced in an aqueous medium using, for example, phosphinic acid and a metal carbonate, metal hydroxide or metal oxide. The (di) phosphinate is originally a monomeric compound, but depending on the reaction conditions, it may be a polymeric phosphinate having a degree of polymerization of 1 to 3 depending on the environment. Examples of phosphinic acid include dimethylphosphinic acid, ethylmethylphosphinic acid, diethylphosphinic acid, methyl-n-propylphosphinic acid, methandi (methylphosphinic acid), benzene-1,4- (dimethylphosphinic acid), and methylphenylphosphine. Examples include acids and diphenylphosphinic acid. Moreover, as a metal component (M) made to react with said phosphinic acid, the metal carbonate, a metal hydroxide, or a metal oxide containing a calcium ion, a magnesium ion, an aluminum ion, and / or a zinc ion is mentioned. Examples of (di) phosphinic acid salts include calcium dimethylphosphinate, magnesium dimethylphosphinate, aluminum dimethylphosphinate, zinc dimethylphosphinate, calcium ethylmethylphosphinate, magnesium ethylmethylphosphinate, aluminum ethylmethylphosphinate, ethyl Zinc methylphosphinate, calcium diethylphosphinate, magnesium diethylphosphinate, aluminum diethylphosphinate, zinc diethylphosphinate, calcium methyl-n-propylphosphinate, magnesium methyl-n-propylphosphinate, methyl-n-propylphosphinic acid Aluminum, zinc methyl-n-propylphosphinate, calcium methylphenylphosphinate, methylphenylphosphite Magnesium acid, aluminum methylphenyl phosphinate, methyl phenyl phosphinate, zinc, calcium diphenyl phosphinate, magnesium diphenyl phosphinate, aluminum diphenyl phosphinate, and zinc diphenyl phosphinate and the like. Diphosphinic acid salts include methandi (methylphosphinic acid) calcium, methandi (methylphosphinic acid) magnesium, methandi (methylphosphinic acid) aluminum, methandi (methylphosphinic acid) zinc, benzene-1,4-di (methylphosphinic acid) Examples include calcium, benzene-1,4-di (methylphosphinic acid) magnesium, benzene-1,4-dimethylphosphinic acid) aluminum, and benzene-1,4-di (methylphosphinic acid) zinc. Among these (di) phosphinic acid salts, aluminum ethylmethylphosphinate, aluminum diethylphosphinate, and zinc diethylphosphinate are particularly preferable from the viewpoints of flame retardancy and electrical characteristics.

  The phosphazene compound is an organic compound having a —P═N— bond in the molecule, preferably at least one compound selected from cyclic phenoxyphosphazenes, chain phenoxyphosphazenes, and crosslinked phenoxyphosphazene compounds. Examples of the cyclic phenoxyphosphazene compound include hexachlorocyclotriphosphazene and octachlorocyclotetraphosphazene from a mixture of cyclic and linear chlorophosphazenes obtained by reacting ammonium chloride and phosphorus pentachloride at a temperature of 120 to 130 ° C. Examples thereof include compounds such as phenoxycyclotriphosphazene, octaphenoxycyclotetraphosphazene, and decaffenoxycyclopentaphosphazene obtained by taking out cyclic chlorophosphazene such as decachlorocyclopentaphosphazene and then substituting it with a phenoxy group. As the chain phenoxyphosphazene compound, for example, hexachlorocyclotriphosphazene obtained by the above method is subjected to reversion polymerization at a temperature of 220 to 250 ° C., and the obtained linear dichlorophosphazene having a polymerization degree of 3 to 10,000 is converted into a phenoxy group. The compound obtained by substituting with is mentioned. Examples of the crosslinked phenoxyphosphazene compound include a compound having a crosslinked structure of 4,4′-sulfonyldiphenylene (bisphenol S residue) and a crosslinked structure of 2,2- (4,4′-diphenylene) isopropylidene group. Compounds having a crosslinked structure of 4,4′-diphenylene groups, such as compounds, compounds having a crosslinked structure of 4,4′-oxydiphenylene groups, compounds having a crosslinked structure of 4,4′-thiodiphenylene groups, etc. Is mentioned. The content of the phenylene group in the crosslinked phenoxyphosphazene compound is usually 50 to 99.9%, preferably 70 to 90%, based on the total number of phenyl groups and phenylene groups in the cyclic phosphazene compound and / or the chain phenoxyphosphazene compound. It is. The crosslinked phenoxyphosphazene compound is particularly preferably a compound having no free hydroxyl group in the molecule.

  An aromatic phosphate ester is a compound produced by a reaction between phosphorus oxychloride and phenols or a mixture of phenols and alcohols. Examples of the aromatic phosphate include triphenyl phosphate, tricresyl phosphate, trixylenyl phosphate, cresyl diphenyl phosphate, 2-ethylhexyl diphenyl phosphate, t-butylphenyl diphenyl phosphate, and bis- (t-butylphenyl). ), Butylated phenyl phosphates such as phenyl phosphate, tris- (t-butylphenyl) phosphate, propylated phenyl phosphates such as isopropylphenyl diphenyl phosphate, bis- (isopropylphenyl) diphenyl phosphate, tris- (isopropylphenyl) phosphate, and the like. It is done.

  The aromatic condensed phosphate ester is a reaction product of phosphorus oxychloride, a divalent phenol compound, and phenol (or alkylphenol). Examples of the aromatic condensed phosphate ester include resorcinol bis-diphenyl phosphate, resorcinol bis-dixylenyl phosphate, bisphenol A bis-diphenyl phosphate, and the like.

  Halogenated phosphoric acid esters are produced by reacting alkylene oxide and phosphorus oxychloride in the presence of a catalyst. For example, as the halogenated phosphate ester, tris (chloroethyl) phosphate, tris (β-chloropropyl) phosphate, tris (dichloropropyl) phosphate, tetrakis (2chloroethyl) dichloroisopentyl diphosphate, polyoxyalkylene bis (dichloroalkyl) ) Phosphate and the like.

  It is preferable that the compounding quantity of a phosphorus flame retardant is 1-50 weight part with respect to 100 weight part of polyamide resins. More preferably, it is 2-40 weight part, More preferably, it is 3-35 weight part.

  Examples of the nitrogen-based flame retardant include a compound that forms a salt of cyanuric acid or isocyanuric acid with a triazine-based compound. A triazine compound and a salt of cyanuric acid or isocyanuric acid are adducts of a triazine compound and cyanuric acid or isocyanuric acid, usually 1 to 1 (molar ratio), sometimes 2 to 1 (molar ratio). ). Of the triazine compounds, those that do not form a salt with cyanuric acid or isocyanuric acid are excluded. Among the salts with cyanuric acid or isocyanuric acid, particularly preferred triazine compounds include melamine, mono (hydroxymethyl) melamine, di (hydroxymethyl) melamine, tri (hydroxymethyl) melamine, benzoguanamine, acetoguanamine, Examples include salts of 2-amido-4,6-diamino-1,3,5-triazine, with melamine, benzoguanamine and acetoguanamine being particularly preferred. Specific examples of salts of triazine compounds with cyanuric acid or isocyanuric acid include melamine cyanurate, mono (β-cyanoethyl) isocyanurate, bis (β-cyanoethyl) isocyanurate, tris (β-cyanoethyl) isocyanurate, etc. Among them, melamine cyanurate is particularly preferable.

  It is preferable that the compounding quantity of a nitrogen-type flame retardant is 1-50 weight part with respect to 100 weight part of polyamide resins. More preferably, it is 3-30 weight part, More preferably, it is 5-20 weight part.

Examples of the metal hydroxide flame retardant include magnesium hydroxide and aluminum hydroxide, and magnesium hydroxide is more preferable. These are usually commercially available and are not particularly limited, such as particle diameter, specific surface area, and shape, but preferably have a particle diameter of 0.1 to 20 μm, a specific surface area of 3 to 75 m ² / g, and a shape. Is preferably spherical, needle-shaped or platelet-shaped. The surface treatment of the metal hydroxide flame retardant may or may not be performed. Examples of the surface treatment method include treatment methods such as coating formation with a thermosetting resin such as a silane coupling agent, an anionic surfactant, a polyfunctional organic acid, and an epoxy resin.

  As for the compounding quantity of a metal hydroxide type flame retardant, 1-50 weight part is preferable with respect to 100 weight part of polyamide resins. Preferably it is 10-50 weight part, More preferably, it is 20-50 weight part.

  The brominated flame retardant is not particularly limited as long as it is a compound containing bromine in the chemical structure, and generally known flame retardants can be used. For example, hexabromobenzene, pentabromotoluene, hexabromobiphenyl, decabromobiphenyl, hexabromocyclodecane, decabromodiphenyl ether, octabromodiphenyl ether, hexabromodiphenyl ether, bis (pentabromophenoxy) ethane, ethylene-bis (tetrabromophthalimide) ), Monomeric organic bromine compounds such as tetrabromobisphenol A, brominated polycarbonates (for example, polycarbonate oligomers produced from brominated bisphenol A or copolymers thereof with bisphenol A), brominated epoxy compounds (for example brominated) For the reaction of diepoxy compounds and brominated phenols produced by the reaction of bisphenol A with epichlorohydrin and epichlorohydrin Monoepoxy compound), poly (brominated benzyl acrylate), brominated polyphenylene ether, brominated bisphenol A, cyanuric chloride and brominated phenol condensate, brominated (polystyrene), poly (brominated styrene), Examples include brominated polystyrene such as crosslinked brominated polystyrene, and halogenated polymeric bromine compounds such as crosslinked or non-crosslinked brominated poly (-methylstyrene). Among them, ethylene bis (tetrabromophthalimide), brominated epoxy polymers Brominated polystyrene, crosslinked brominated polystyrene, brominated polyphenylene ether and brominated polycarbonate are preferred, and brominated polystyrene, crosslinked brominated polystyrene, brominated polyphenylene ether and brominated polycarbonate are preferably used. It can be.

  The blending amount of the brominated flame retardant is preferably 1 to 50 parts by weight with respect to 100 parts by weight of the polyamide resin. More preferably, it is 10-50 weight part, More preferably, it is 20-50 weight part.

  In addition, it is also preferable to add a flame retardant aid used synergistically to improve flame retardancy by using in combination with the brominated flame retardant, for example, antimony trioxide, antimony tetraoxide, Antimony oxide, antimony deoxydioxide, crystalline antimonic acid, sodium antimonate, lithium antimonate, barium antimonate, antimony phosphate, zinc borate, zinc stannate, basic zinc molybdate, calcium zinc molybdate, molybdenum oxide, oxidation Examples include zirconium, zinc oxide, iron oxide, red phosphorus, swellable graphite, and carbon black. Of these, antimony trioxide and antimony pentoxide are more preferable. It is preferable that the compounding quantity of a flame retardant adjuvant is 0.2-30 weight part with respect to 100 weight part of polyamide resins from the point of a flame retardance improvement effect. More preferably, it is 1-20 weight part.

  Furthermore, the polyamide resin composition for parts in an engine room of the present invention has various additives such as antioxidants and heat stabilizers (hindered phenol-based, hydroquinone-based, phosphite) within the range not impairing the effects of the present invention. Systems and their substitutes, copper halides, iodine compounds, etc.), weathering agents (resorcinols, salicylates, benzotriazoles, benzophenones, hindered amines, etc.), mold release agents and lubricants (aliphatic alcohols, aliphatic amides) , Aliphatic bisamides, bisureas and polyethylene waxes), pigments (cadmium sulfide, phthalocyanine, carbon black, etc.), dyes (nigrosine, aniline black, etc.), plasticizers (octyl p-oxybenzoate, N-butylbenzenesulfonamide) Etc.), antistatic agent (alkyl sulfate type a) On antistatic agents, quaternary ammonium salt type cationic antistatic agents, nonionic antistatic agents such as polyoxyethylene sorbitan monostearate, betaine-based amphoteric antistatic agent, etc.) can be blended.

  Examples of the hindered phenol antioxidant include 2,4-dimethyl-6-t-butylphenol, 2,6-di-t-butylphenol, 2,6-di-t-butyl-p-cresol, 2,6- Di-t-butyl-4-ethylphenol, 4,4′-butylidenebis (6-t-butyl-3-methylphenol), 2,2′-methylene-bis (4-methyl-6-t-butylphenol), 2,2′-methylene-bis (4-ethyl-6-tert-butylphenol), octadecyl-3- (3 ′, 5′-di-tert-butyl-4′-hydroxyphenyl) propionate, tetrakis [methylene-3 -(3,5-di-tert-butyl-4-hydroxyphenyl) propionate] methane, pentaerythrityltetrakis [3- (3 ', 5'-di-tert-butyl-4'-hydride) Xylphenyl) propionate], 3,9-bis [2- (3- (3-tert-butyl-4-hydroxy-5-methylphenyl) propionyloxy) -1,1-dimethylethyl] -2,4,8, 10-tetraoxaspiro [5,5] undecane, 1,1,3-tris (2-methyl-4-hydroxy-5-di-t-butylphenyl) butane, tris (3,5-di-t-butyl) -4-hydroxybenzyl) isocyanurate, triethylene glycol-bis [3- (3-tert-butyl-5-methyl-4-hydroxyphenyl) propionate], 1,6-hexanediol-bis [3- (3 5-di-t-butyl-4-hydroxyphenyl) propionate], 2,4-bis- (n-octylthio) -6- (4-hydroxy-3,5-di-t-butyla) Nilino) -1,3,5-triazine, 2,2-thio-diethylenebis [3- (3,5-di-t-butyl-4-hydroxyphenyl) propionate), N, N′-hexamethylene-bis (3,5-di-tert-butyl-4-hydroxyhydrocinnamide), 3,5-di-tert-butyl-4-hydroxybenzylphosphonate-diethyl ester, 1,3,5-trimethyl-2, 4,6-tris (3,5-di-t-butyl-4-hydroxybenzyl) benzene, 2,4-bis [(octylthio) methyl] -o-cresol, isooctyl-3- (3,5-di- t-butyl-4-hydroxyphenyl) propionate and the like. In particular, an ester type polymer hindered phenol type is preferable, and specifically, tetrakis [methylene-3- (3 ′, 5′-di-t-butyl-4′-hydroxyphenyl) propionate] methane, pentaerythrityl tetrakis. [3- (3 ′, 5′-di-t-butyl-4′-hydroxyphenyl) propionate], 3,9-bis [2- (3- (3-t-butyl-4-hydroxy-5-methyl) Phenyl) propionyloxy) -1,1-dimethylethyl] -2,4,8,10-tetraoxaspiro [5,5] undecane and the like are preferably used.

  Specific examples of phosphite compounds include bis (2,6-di-t-butyl-4-methylphenyl) pentaerythritol-di-phosphite, bis (2,4-di-t-butylphenyl) pentaerythritol. -Di-phosphite, bis (2,4-di-cumylphenyl) pentaerythritol-di-phosphite, tris (2,4-di-t-butylphenyl) phosphite, tetrakis (2,4-di-t- Butylphenyl) -4,4'-bisphenylene phosphite, di-stearyl pentaerythritol di-phosphite, triphenyl phosphite, 3,5-di-butyl-4-hydroxybenzyl phosphonate diethyl ester It is done.

  These antioxidants may have a synergistic effect when two or more are combined, and may be used in combination. Although there is no restriction | limiting in particular in the compounding quantity of antioxidant, 0.01-20 weight part is preferable with respect to 100 weight part of polyamide resins.

  Specific examples of the heat stabilizer include copper fluoride, copper chloride, copper bromide, copper iodide copper halide, copper oxide, copper sulfate, copper nitrate, inorganic acid copper compounds, copper acetate, lauric acid, etc. Although organic acid copper compounds, such as copper, copper stearate, copper naphthenate, and caprate, are mentioned, Among these, copper iodide and copper acetate are preferable, and copper iodide is more preferable. These compounding quantities are 0.01-0.3 weight part with respect to 100 weight part of polyamide resins, Most preferably, it is 0.01-0.1 weight part.

  Furthermore, higher heat resistance can be imparted by using in combination with a copper compound and an alkali halide. Examples of the alkali halide include potassium iodide and magnesium iodide, and potassium iodide is preferable. As a preferable compounding quantity, the halogen atom in this alkali halide is a ratio of 0.3-4 atom with respect to 1 atom of copper in the said copper compound.

  As a method for producing a polyamide resin composition for an engine compartment component of the present invention, for example, a raw material polyamide resin, an inorganic filler, if necessary, an impact resistance improving material, a flame retardant and / or other kinds of polymers, etc. are publicly known. Examples thereof include a method of supplying to a melt kneader and performing melt kneading. Examples of the melt kneader include a single or twin screw extruder, a Banbury mixer, a kneader, and a mixing roll. When a melt kneader is used as a method for uniformly dispersing these inorganic fillers, impact modifiers, flame retardants and / or other types of polymers and various additives in a polyamide resin, the L / D ( It is effective to control (screw length / screw diameter), presence / absence of vent, kneading temperature, residence time, addition position and amount of each component. In general, it is preferable to lengthen the L / D of the melt-kneader and lengthen the residence time in order to promote uniform dispersion of each component in the resin composition.

  The polyamide resin composition for automotive engine compartment components of the present invention can be molded into a desired shape by any molding method such as injection molding, extrusion molding, blow molding, vacuum molding and the like.

  Even when the polyamide resin composition is used in a high temperature environment, a decrease in elastic modulus can be suppressed, and a molded product having a small dimensional change from a room temperature to a high temperature environment can be obtained. Further, since the inherent water absorption of the polyamide resin is low, blistering due to evaporation of water absorbed in the molded article under a high temperature environment can be suppressed. In particular, it can be suitably used as a part in an automobile engine room used in a high temperature environment.

  Examples of the engine room parts in which the polyamide resin composition is used include engine body parts, engine intake system parts, engine cooling system parts, engine lubrication system parts, engine valve system parts, engine covers, and the like. As engine body parts, engine mount, rocker cover, chain guide, and engine intake system parts as air cleaner, air flow meter, EGR parts, intake manifold, throttle body, intake duct, intake pipe, resonator, canister, engine cooling system Parts include radiator support, water pump inlet, water pump outlet, water pump impeller, thermostat housing, cooling fan, fan shroud, reservoir tank, reservoir tank cap, engine lubrication parts include oil pump, oil filter housing, oil Filler caps, oil level gauges, power steering tanks, engine valve system parts Imming belt cover, timing belt tensioner, engine fuel supply system parts are fuel rail, fuel strainer, other parts are harness connector, guide, alternator cover, distributor cover, brake master cylinder, switch boot, lamp waterproof cover , Connector cover, rubber hook, suspension boot, suspension upper mount, suspension bush, stabilizer bush, steering rack boot, steering rack bush, plug cord cap, molded packing, battery terminal cover, and the like.

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

[Sulfuric acid relative viscosity (ηr)]
Measurement was performed using an Ostwald viscometer at a concentration of 0.01 g / ml in 25% sulfuric acid in 98% sulfuric acid.

[Saturated water absorption]
A square plate having a thickness of 100 mm × 150 mm × 3 mm was calculated from an increase in weight after being left in an atmosphere of 60 ° C. and a relative humidity of 95% for 500 hours. However, only in Example 9 and Comparative Example 13, a test piece having a length of 55 mm, a width of 13 mm, and a thickness of 2 mm collected from a box-shaped molded product was used instead of the sample.

[Viscoelasticity]
Using a sample obtained by cutting an Izod test piece having a width of 13 mm and a thickness of 3 mm into a length of 55 mm, using a DMS6100 made by SII Nanotechnology, the center of the 55 mm × 13 mm surface of the sample is bent at a frequency of 1 Hz, and the distance between chucks. Measured at 20 mm, heating rate 2 ° C./min, 20 ° C. to 200 ° C., storage modulus at 30 ° C. and 110 ° C., displacement at 30 to 110 ° C. (55 mm × 13 mm sample perpendicular to 55 mm × 13 mm plane) Displacement). Further, the peak top value of tan δ corresponding to the glass transition temperature of the polyamide resin and the temperature thereof were determined. However, only in Example 9 and Comparative Example 13, a test piece having a length of 55 mm, a width of 13 mm, and a thickness of 2 mm collected from a box-shaped molded product was used instead of the sample.

[Thermal characteristics]
Using a robot DSCRDC220 manufactured by SII Nanotechnology, about 5 mg of the polyamide resin composition was precisely weighed, and the temperature drop crystallization temperature, melting point, and heat of fusion of the polyamide resin were measured under a nitrogen atmosphere under the following conditions. The temperature of the exothermic peak observed when the polyamide resin composition is heated to a melting point of the polyamide resin + 35 ° C. to a molten state and then cooled to 30 ° C. at a temperature lowering rate of 20 ° C./min (temperature-falling crystallization). Temperature: Tc) was determined. Subsequently, after holding at 30 ° C. for 3 minutes, the temperature of the endothermic peak (melting point: Tm) and the heat of fusion (ΔHm) observed when the temperature is raised to the melting point of the polyamide resin + 35 ° C. at a rate of temperature increase of 20 ° C./min. ) In addition, (DELTA) Hm divided the heat of fusion of the polyamide resin composition by the compounding ratio of the polyamide resin, and described it as the heat of fusion of the polyamide resin alone.

[Average particle size of non-fibrous inorganic filler]
The average particle size (D50) of the non-fibrous inorganic filler was measured using a laser particle size distribution meter (SALD-2100: manufactured by Shimadzu Corporation).

Reference Example 1 (Manufacture of nylon 410)
Tetramethylenediamine (Kanto Chemical) and sebacic acid (Tokyo Kasei) equimolar salt (nylon 410 salt) 700 g, tetramethylenediamine 5.3 g (2.5 mol% with respect to nylon 410 salt), ion-exchanged water 300 g, After charging into a 3 L pressure vessel with a stirring blade and replacing with nitrogen, the internal pressure of the can was increased to 0.05 MPa with nitrogen. With this pressure vessel sealed, heating was started by setting the heater temperature to 260 ° C. After 40 minutes, the internal temperature of the can reached 150 ° C., and the internal pressure of the can reached 0.3 MPa. The pressure inside the can was maintained at 0.3 MPa while distilling water. When the inside temperature of the can reached 250 ° C., the heater set temperature was changed to 280 ° C., the pressure release was started, and the pressure inside the can was reduced to zero over 30 minutes while distilling water. At this time, the inside temperature of the can was 275 ° C. By holding for 2 hours under a nitrogen flow, the temperature in the can reached 280 ° C. The contents were taken out from the discharge port at the bottom of the pressure vessel in a gut shape and pelletized to obtain nylon 410 having ηr = 2.8.

Reference Example 2 (Manufacture of nylon 46)
Tetramethylenediamine (Kanto Chemical) and adipic acid (Tokyo Kasei) equimolar salt (nylon 46 salt) 800 g, tetramethylenediamine 12.0 g (4.00 mol% with respect to nylon 46 salt), ion-exchanged water 65 g, After charging into a 3 L pressure vessel with a stirring blade and replacing with nitrogen, the internal pressure of the can was increased to 0.05 MPa with nitrogen. The sealed pressure vessel was heated by setting the heater temperature to 245 ° C. After 2 hours, the internal temperature of the can reached 220 ° C. and the internal pressure of the can reached 1.35 MPa. Then, it discharged on the cooling belt from the pressure vessel, and obtained the nylon 46 low-order condensate. This was subjected to solid phase polymerization under reduced pressure (50 Pa) at 260 ° C. for 20 hours to obtain nylon 46 having ηr = 3.1.

Examples 1-3, Comparative Examples 1-8
Using a twin screw extruder (TEX30 type manufactured by Nippon Steel), polyamide resin, talc, and impact resistance improver were supplied so as to have the composition shown in Table 1, and melt kneaded. In Examples 1 to 3 and Comparative Examples 1 to 3, a mixture of polyamide resin and talc was supplied from the main feeder (upstream supply port). In Comparative Examples 4 to 7, a single polyamide resin was supplied from the main feeder. In Comparative Example 8, the polyamide resin was supplied from the main feeder (upstream supply port), and the impact resistance improving material was supplied from the side feeder (downstream supply port). The melt kneading temperature was the melting point of the polyamide resin + 20 ° C., and the screw rotation speed was 250 rpm. The extruded gut was pelletized and then vacuum dried at 80 ° C. for 24 hours. Each test piece was prepared with an injection molding machine (SG75H-MIV manufactured by Sumitomo Heavy Industries, Ltd., the cylinder temperature was set to melting point + 20 ° C., the mold temperature was set to 80 ° C., and the injection pressure was set to the lower limit pressure +0.5 MPa), and saturated water absorption was performed. The rate, viscoelasticity and thermal properties were evaluated. The test piece was stored in a seal bag immediately after injection molding so as not to absorb water. Table 1 shows the results. In addition, the raw material of a polyamide resin composition used the following.
Nylon 410 (N410): Reference Example 1
Nylon 610 (N610): CM2001 (manufactured by Toray), ηr = 2.70
Nylon 66 (N66): CM3001N (manufactured by Toray), ηr = 2.95
Nylon 46 (N46): Reference Example 2
Nylon 6 (N6): CM1017 (manufactured by Toray), ηr = 2.65
Talc: manufactured by Nippon Talc Co., Ltd., P-6 (average particle size: 4 μm)
Impact resistance improver: Mitsui Chemicals, acid-modified ethylene / butene-1 copolymer, TAFMER MH5020

  From the comparison between Example 1 and Comparative Examples 1, 2, 4 to 6, nylon 410 has a relatively large ratio of storage elastic modulus at 30 ° C. to storage elastic modulus at 110 ° C., which is 30 ° C. compared to nylon 610 and nylon 66. It can be seen that the displacement at ˜110 ° C. is small. Further, from the comparison between Example 1 and Comparative Example 2, nylon 410 exhibits a lower storage elastic modulus at 30 ° C. than nylon 66. Further, from comparison between Example 1 and Comparative Example 3, nylon 410 has a lower saturated water absorption than nylon 46, and a molded product using this as a base polymer is caused by water evaporation when used in a high temperature environment. It can be expected that swelling can be suppressed.

  Nylon 46 has the largest ΔHm as an index of crystallinity, and its storage elastic modulus is higher than that of nylon 66 at 30 ° C. and 110 ° C. On the other hand, ΔHm of nylon 410 is smaller than that of nylon 66, and correspondingly, the storage elastic modulus at 30 ° C. is low, but the storage elastic modulus at 110 ° C. is high. In nylon 410, since the value of the peak top of tan δ corresponding to the glass transition temperature is small, it is considered that the mobility of the amorphous part is suppressed. From the above, it can be seen that nylon 410 has excellent characteristics as a polyamide resin which is a constituent of the present invention.

  According to the comparison between Example 1 and Comparative Examples 1 and 2, when nylon 410 is used as the polyamide resin, the storage elastic modulus at 110 ° C./the storage elastic modulus at 30 ° C. is the largest, and the displacement of 30 to 110 ° C. small.

  From the comparison between Example 1 and Comparative Examples 1 to 7, Tm-Tc, which is an index of the crystallization rate, is reduced by talc blending in any polymer, and the crystallization rate is improved. Nylon 410 has the largest crystallization promoting effect by blending talc, and a faster molding cycle can be expected.

  As a result of comparison between Example 1 and Comparative Example 4, by adding talc, the peak top value of tan δ is reduced and the displacement at 30 to 110 ° C. is reduced.

Examples 4-8, Comparative Examples 9-12
Using a twin screw extruder (Nippon Steel Works TEX30 type), polyamide resin and talc from the main feeder (upstream supply port), glass fiber or carbon fiber from the side feeder (downstream supply port), respectively Table 2 or The composition shown in Table 3 was supplied and melt-kneaded. The melt kneading temperature was the melting point of the polyamide resin + 20 ° C., and the screw rotation speed was 250 rpm. The extruded gut was pelletized and then vacuum dried at 80 ° C. for 24 hours. From the obtained pellets, test pieces were prepared in the same manner as in Example 1, and the saturated water absorption, viscoelasticity, and thermal characteristics were evaluated. Tables 2 and 3 show the results. The polyamide resin and talc used the same raw materials as in Table 1, and the glass fibers and carbon fibers shown below were used.
Circular cross-section glass fiber (circular GF): T-275H manufactured by Nippon Electric Glass Co., Ltd. (cross-sectional diameter: 10.5 μm, surface treatment agent: silane coupling agent, fiber length: 3 mm)
Flat cross-section glass fiber (flat GF): CSG 3PA-820S manufactured by Nittobo Co., Ltd. (major axis 28 μm, minor axis 7 μm, oblateness ratio 4.0, cross-sectional shape: oval, surface treatment agent: silane coupling agent, fiber length 3 mm )
Carbon fiber: Toray TV14-006

  From the comparison between Examples 4 and 6, the amount of deformation at 30 ° C. to 110 ° C. is smaller when flat GF is used, and the dimensional stability between room temperature and high temperature is excellent.

Example 9 and Comparative Example 13
The polyamide resin composition produced in Example 4 and Comparative Example 10, assuming parts in an automobile engine room, was injected into an injection molding machine (J220EII-2M manufactured by Nippon Steel Works, melting point + 25 ° C., mold temperature 80 ° C. The injection pressure was set to the lower limit pressure +1.0 MPa) to obtain a box-shaped product (length 100 mm, width 60 mm, height 25 mm, wall thickness 2 mm). The obtained molded product was cut to obtain a test piece having a length of 55 mm, a width of 13 mm, and a thickness of 2 mm, and measured for saturated water absorption, viscoelasticity, and thermal characteristics. The results are shown in Table 4.

  The polyamide resin composition of the present invention can be suitably used for automotive engine room parts by taking advantage of its high temperature rigidity.

Claims (8)

0.01 parts by weight or more and 200 parts by weight of inorganic filler per 100 parts by weight of polyamide resin obtained by polycondensation of monomers mainly composed of tetramethylenediamine and aliphatic dicarboxylic acid having 7 or more carbon atoms A polyamide resin composition comprising the following: ratio of storage elastic modulus at 110 ° C. measured in bending mode to storage elastic modulus at 30 ° C. measured in bending mode (storage elastic modulus at 110 ° C./30° C. The storage resin modulus of the tan δ corresponding to the glass transition temperature of the polyamide resin is 0.098 or less. The polyamide resin composition for parts in an automobile engine room according to claim 1, wherein the inorganic filler includes a non-fibrous inorganic filler. The polyamide resin composition for automotive engine compartment parts according to claim 2, wherein the non-fibrous inorganic filler is at least one selected from the group consisting of talc, wollastonite, mica and kaolin. The polyamide resin composition for parts in an automobile engine room according to claim 2 or 3, wherein the inorganic filler further contains a fibrous inorganic filler. The polyamide resin composition for automotive engine compartment parts according to claim 4, wherein the fibrous inorganic filler is glass fiber and / or carbon fiber. The polyamide resin composition for parts in an automobile engine room according to any one of claims 1 to 5, wherein the saturated water absorption is 6.0% by weight or less. The automobile engine room according to any one of claims 1 to 6, wherein the aliphatic dicarboxylic acid having 7 or more carbon atoms is at least one selected from the group consisting of azelaic acid, sebacic acid, undecanedioic acid and dodecanedioic acid. Polyamide resin composition for internal parts. A part in an automobile engine room formed by molding the polyamide resin composition according to claim 1.