JP2019001996A - Polyamide resin composition and molded article obtained by molding the same - Google Patents

Abstract

To provide a polyamide resin composition capable of simultaneously satisfying high fluidity and low metal corrosiveness while maintaining reflow heat resistance and flame retardancy.SOLUTION: The polyamide resin composition contains a polyamide (A1), a polyamide (A2), a flame retardant (B), and a fibrous reinforcing material (C). The polyamide (A1) contains a dicarboxylic acid component containing terephthalic acid and a diamine component and has a melting point of 270°C or higher. The polyamide (A2) has a melting point lower than 270°C. The content of the polyamide (A1) is 30 mass% or more and less than 50 mass% based on the total content of (A1) and (A2).SELECTED DRAWING: None

Description

  The present invention relates to a polyamide resin composition having flame retardancy.

  Polyamide is excellent in heat resistance and mechanical properties, and is used as a constituent material for many electric / electronic parts and parts around automobile engines.

  Among these parts, polyamides constituting electric / electronic parts are required to have higher flame retardancy. As a method for imparting flame retardancy to polyamide, a method using a flame retardant is usually performed. In recent years, due to the increase in environmental awareness, halogen-based flame retardants have been avoided, and generally non-halogen-based flame retardants have been used.

  In addition, surface mounting is the mainstream for mounting electrical / electronic components, and the polyamide constituting the components is exposed to a high temperature of about 260 ° C. in the reflow process. Therefore, the use of a heat-resistant polyamide having a reflow heat resistance and a melting point of 270 ° C. or higher is increasing as a polyamide. As the heat-resistant polyamide having a melting point of 270 ° C. or higher, semi-aromatic polyamide, polyamide 46 or the like is generally used.

  For example, Patent Document 1 discloses a semi-aromatic polyamide resin composition using a phosphinic acid metal salt as a non-halogen flame retardant, and flame retardant standard UL94V in a 1/32 inch (0.79 mm) molded product. It is disclosed that it satisfies the −0 standard and has reflow heat resistance and fluidity at a thickness of 0.5 mm.

However, electric and electronic components are becoming smaller year by year, and thinner performance is required. In particular, regarding flame retardancy and fluidity, generally, the thinner the wall, the lower the performance.
In addition, since heat-resistant polyamides have a high processing temperature due to their high melting point, in heat-resistant polyamide resin compositions containing phosphinic acid metal salts, screws and dies for extruders and screws and molds for molding machines are used during melt processing. There was a problem of metal corrosiveness such as violent wear of metal parts.

  Thus, in designing a heat-resistant polyamide suitable for electric / electronic parts, it is very important to achieve both reflow heat resistance, flame retardancy, fluidity, and low metal corrosivity.

With respect to these problems, Patent Document 2 discloses a material using a specific semiaromatic polyamide and a specific aliphatic polyamide in a weight ratio of 75/25 to 98/2. This material has a molding process temperature of 340 ° C., and requires a molding process at a high temperature. Since the metal corrosivity increases as the temperature increases, in this material, it is necessary to lower the molding processing temperature in order to reduce the metal corrosiveness, but if the molding processing temperature is lowered, the fluidity is significantly impaired, There has been a problem that molding is difficult.
Patent Document 3 discloses a material using a specific semi-aromatic polyamide and a specific aliphatic polyamide in a weight ratio of 50/50 to 75/25. Although this material has improved fluidity as compared with the material disclosed in Patent Document 2, the metal corrosivity has not been sufficiently reduced.

International Publication No. 2008/126381 Special table 2014-517102 gazette Special table 2014-521765 gazette

  This invention solves the said subject in a flame-retardant polyamide resin composition, Comprising: While maintaining reflow heat resistance and flame retardance, the polyamide which can satisfy | fill high fluidity and low metal corrosiveness simultaneously It aims at providing a resin composition.

  As a result of intensive studies to solve the above problems, the inventors of the present invention have identified a specific polyamide (A1) and a specific polyamide (A2) as a polyamide constituting the flame-retardant polyamide resin composition. The inventors have found that the above-mentioned problems can be solved by using a polyamide contained in a ratio, and have reached the present invention. That is, the gist of the present invention is as follows.

(1) Polyamide (A1), polyamide (A2), flame retardant (B), and fibrous reinforcement (
C) a polyamide resin composition comprising:
The polyamide (A1) contains a dicarboxylic acid component containing terephthalic acid (TPA) and a diamine component, and has a melting point of 270 ° C. or higher.
The polyamide (A2) has a melting point of less than 270 ° C.,
The polyamide resin composition, wherein the content of the polyamide (A1) is 30% by mass or more and less than 50% by mass with respect to the total content of (A1) and (A2).
(2) The polyamide resin composition according to (1), wherein the flame retardant (B) is a non-halogen flame retardant.
(3) The polyamide resin composition according to (1), wherein the flame retardant (B) is a compound represented by the following general formula (I) or (II).
(In the formula, R ¹ , R ² , R ⁴ and R ⁵ each independently represents a linear or branched alkyl group having 1 to 16 carbon atoms or a phenyl group. R ³ is linear or branched. The chain represents an alkylene group having 1 to 10 carbon atoms, an arylene group having 6 to 10 carbon atoms, an arylalkylene group, or an alkylarylene group, and M represents a calcium ion, an aluminum ion, a magnesium ion, or a zinc ion. Is 2 or 3. n, a, and b are integers satisfying the relational expression 2 × b = n × a.)
(4) The dicarboxylic acid component of the polyamide (A1) further contains isophthalic acid (IPA), and the mass ratio of terephthalic acid to isophthalic acid (TPA / IPA) is 99.9 / 0.1 to 95/5. The polyamide resin composition according to any one of (1) to (3).
(5) The polyamide (A1) includes a monocarboxylic acid component having a molecular weight of 140 or more, and the content of the monocarboxylic acid component is 0.3 to 4.0 with respect to all monomer components constituting the polyamide (A1). The polyamide resin composition according to any one of (1) to (4), wherein the polyamide resin composition is mol%.
(6) A molded article obtained by molding the polyamide resin composition according to any one of (1) to (5) above.

  According to the present invention, a polyamide resin composition capable of simultaneously satisfying high fluidity and low metal corrosivity by containing a specific polyamide (A1) and a specific polyamide (A2) at a specific mass ratio. Can be provided. Moreover, it can provide a molded product having sufficient reflow heat resistance and flame retardancy. It is very surprising that reflow heat resistance can be maintained by containing a polyamide (A1) having a high melting point despite containing a large amount of polyamide (A2) having a low melting point. Further, the polyamide resin composition of the present invention can lower the molding processing temperature, can achieve both flame retardancy and low metal corrosiveness, and can maintain high fluidity even at such a low molding processing temperature. Became possible.

It is a figure which shows the apparatus for evaluating metal corrosivity.

Hereinafter, the present invention will be described in detail.
The polyamide resin composition of the present invention contains polyamide (A1), polyamide (A2), flame retardant (B), and fibrous reinforcing material (C).

The polyamide (A1) in the present invention contains a dicarboxylic acid component and a diamine component, and the dicarboxylic acid component constituting the polyamide (A1) needs to contain terephthalic acid (TPA).
Examples of dicarboxylic acids other than terephthalic acid in the dicarboxylic acid component include isophthalic acid (IPA) and derivatives thereof, naphthalenedicarboxylic acid and derivatives thereof, adipic acid, sebacic acid, azelaic acid and / or dodecanedioic acid, Of these, isophthalic acid is preferred.

  When terephthalic acid and isophthalic acid are used in combination as the dicarboxylic acid, the mass ratio of terephthalic acid to isophthalic acid (TPA / IPA) is preferably 99.9 / 0.1 to 70/30, and 99.9 / 0. It is more preferable to set it as 0.1-90 / 10, and it is still more preferable to set it as 99.9 / 0.1-95 / 5. By setting the mass ratio to 99.9 / 0.1 to 70/30, both fluidity and flame retardancy can be achieved.

  Examples of the diamine component constituting the polyamide (A1) include C6-C20 aromatic diamine, C6-C20 alicyclic diamine, butanediamine, hexamethylenediamine, 2-methylpentamethylenediamine, 2-methyloctamethylenediamine, Examples include trimethylhexamethylenediamine, 1,8-diaminooctane, 1,9-diaminononane, 1,10-diaminodecane, 1,11-diaminoundecane, 1,12-diaminododecane and the like.

  As the polyamide (A1) obtained from the monomer component, for example, polyamide 4T, polyamide 6T, polyamide 7T, polyamide 8T, polyamide 9T, polyamide 10T, polyamide 11T, polyamide 12T and other semi-aromatic polyamides, and copolymers For example, when the diamine has 6 carbon atoms, PA6T / 6, PA6T / 12, PA6T / 66, PA6T / 610, PA6T / 612, PA6T / 6I, PA6T / 6I / 66, PA6T / M5T (M5: methylpenta Diamine), PA6T / TM6T (TM6: 2,2,4- or 2,4,4-trimethylhexamethylenediamine), PA6T / MMCT (MMC: 4,4'-methylenebis (2-methylcyclohexylamine)), etc. Can be mentioned. As the polyamide (A1), these polyamides may be used alone, or a copolymer or a mixture of two or more kinds of polyamides may be used.

The polyamide (A1) in the present invention is required to have a melting point of 270 ° C. or higher, preferably 280 ° C. or higher, and more preferably 300 ° C. or higher. Polyamide (A1) has a heat resistance due to a melting point of 270 ° C. or higher, and can withstand a reflow process in which the maximum temperature is about 260 ° C. On the other hand, when the melting point of the polyamide (A1) exceeds 350 ° C., the decomposition temperature of the amide bond is about 350 ° C., so that carbonization and decomposition may proceed during melt processing. Moreover, since it is necessary to make the temperature at the time of a shaping | molding process more than melting | fusing point, metal corrosion will advance more.
From the viewpoint of the melting point, the polyamide (A1) is preferably polyamide 4T, polyamide 6T, polyamide 8T, polyamide 9T, polyamide 10T, polyamide 11T, polyamide 12T and copolymers thereof. Furthermore, polyamide 4T, polyamide 6T, polyamide 9T, polyamide 10T, and copolymers thereof are more preferable because they have an excellent balance between water absorption and heat resistance, and are particularly excellent in reflow heat resistance. Polymers are particularly preferred.

  In the present invention, the polyamide (A1) preferably contains a monocarboxylic acid component as a constituent component. The content of the monocarboxylic acid component is preferably 0.3 to 4.0 mol%, and preferably 0.3 to 3.0 mol% with respect to all monomer components constituting the polyamide (A1). More preferably, it is 0.3 to 2.5 mol%, more preferably 0.8 to 2.5 mol%. By containing a monocarboxylic acid component within the above range, the molecular weight distribution at the time of polymerization can be reduced, the releasability at the time of molding can be improved, or the amount of gas generated at the time of molding can be suppressed. I can do it. On the other hand, when the content of the monocarboxylic acid component exceeds the above range, mechanical properties and flame retardancy may be deteriorated. In the present invention, the content of the monocarboxylic acid refers to the ratio of the monocarboxylic acid residue in the polyamide (A1), that is, the proportion of the monocarboxylic acid from which the terminal hydroxyl group is eliminated.

  The polyamide (A1) preferably contains a monocarboxylic acid having a molecular weight of 140 or more as a monocarboxylic acid component, and more preferably contains a monocarboxylic acid having a molecular weight of 170 or more. When the molecular weight of the monocarboxylic acid is 140 or more, the releasability is improved, the amount of gas generated can be suppressed at the temperature during the molding process, and the molding fluidity can also be improved.

  Examples of the monocarboxylic acid component include aliphatic monocarboxylic acid, alicyclic monocarboxylic acid, and aromatic monocarboxylic acid. Among them, the amount of generated gas of the polyamide-derived component is reduced, mold contamination is reduced, and release is performed. An aliphatic monocarboxylic acid is preferable because it can improve moldability.

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. Of these, 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, 1-naphthoic acid, 2-naphthoic acid, and derivatives thereof. .

  The monocarboxylic acid component may be used alone or in combination. 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 refers to the molecular weight of the starting monocarboxylic acid.

  The polyamide (A1) can be produced using a conventionally known method such as a heat polymerization method or a solution polymerization method. Of these, the heat polymerization method is preferably used because it is industrially advantageous.

The polyamide (A2) in the present invention needs to have a melting point of less than 270 ° C.
As the polyamide (A2), polyamide 6, polyamide 66, polyamide 10, polyamide 610, polyamide 612, polyamide 1010, polyamide 11, polyamide 12, a copolymer of metaxylylenediamine and adipic acid (polyamide MXD6), polyamide 66 / 6 copolymer, copolymer of paraaminomethylbenzoic acid and ε-caprolactam (polyamide AHBA), 2,2,4- / 2,4,4-trimethylhexamethylenediamine terephthalate as a main component Polyamide (polyamide THDT, THDT / 6I) and the like can be mentioned. Among these, from the viewpoint of fluidity, polyamide 6, polyamide 66, polyamide 10, polyamide 610, polyamide 612, polyamide 1010, polyamide 11, and polyamide 12 are preferable, and polyamide 6 and polyamide 66 are more preferable.

  In the polyamide resin composition of the present invention, the content of the polyamide (A1) needs to be 30% by mass or more and less than 50% by mass with respect to the total content of the polyamide (A1) and the polyamide (A2). Yes, preferably 35 to 49% by mass, more preferably 41 to 49% by mass. When the content of the polyamide (A1) is 50% by mass or more, the resin composition cannot lower the molding processing temperature, the flame retardancy is lowered, and the metal corrosivity is increased. On the other hand, if the content of polyamide (A1) is less than 30% by mass, the resin composition has insufficient reflow heat resistance and cannot be practically used.

  The polyamide resin composition of the present invention contains a flame retardant (B). Examples of the flame retardant (B) include halogen flame retardants, phosphorus flame retardants, nitrogen flame retardants, nitrogen-phosphorus flame retardants, and inorganic flame retardants. preferable. Among non-halogen flame retardants, phosphorus flame retardants are more preferable, particularly from the viewpoints of heat resistance and flame retardancy.

Examples of the phosphorus-based flame retardant include phosphinic acid metal salts. Examples of the phosphinic acid metal salt include a phosphinic acid metal salt represented by the following general formula (I) and a diphosphinic acid metal salt represented by the general formula (II).

In the formula, R ¹ , R ² , R ⁴ and R ⁵ are each independently required to be a linear or branched alkyl group having 1 to 16 carbon atoms or a phenyl group, and having 1 to 8 carbon atoms. Are preferably an alkyl group or a phenyl group, and are a methyl group, an ethyl group, an n-propyl group, an isopropyl group, an n-butyl group, a tert-butyl group, an n-pentyl group, an n-octyl group, or a phenyl group. More preferred is an ethyl group. R ¹ and R ² and R ⁴ and R ⁵ may form a ring with each other.
R ³ is required to be a linear or branched alkylene group having 1 to 10 carbon atoms, an arylene group having 6 to 10 carbon atoms, an arylalkylene group, or an alkylarylene group. Examples of the linear or branched alkylene group having 1 to 10 carbon atoms include methylene group, ethylene group, n-propylene group, isopropylene group, isopropylidene group, n-butylene group, tert-butylene group, n- A pentylene group, an n-octylene group, and an n-dodecylene group may be mentioned. Examples of the arylene group having 6 to 10 carbon atoms include a phenylene group and a naphthylene group. Examples of the alkylarylene group include a methylphenylene group, an ethylphenylene group, a tert-butylphenylene group, a methylnaphthylene group, an ethylnaphthylene group, and a tert-butylnaphthylene group. Examples of the arylalkylene group include a phenylmethylene group, a phenylethylene group, a phenylpropylene group, and a phenylbutylene group.
M represents a metal ion. Examples of the metal ions include calcium ions, aluminum ions, magnesium ions, and zinc ions. Aluminum ions and zinc ions are preferable, and aluminum ions are more preferable.
m and n represent the valence of the metal ion. m is 2 or 3. a represents the number of metal ions, b represents the number of diphosphinic acid ions, and n, a, and b are integers satisfying the relational expression “2 × b = n × a”.

  Phosphinic acid metal salts and diphosphinic acid metal salts are produced in aqueous solutions using the corresponding phosphinic acid and diphosphinic acid and metal carbonates, metal hydroxides or metal oxides, respectively, and usually exist as monomers. Depending on the reaction conditions, it may be present in the form of a polymeric phosphinate having a degree of condensation of 1-3.

  Specific examples of the phosphinic acid salt represented by the general formula (I) include, for example, calcium dimethylphosphinate, magnesium dimethylphosphinate, aluminum dimethylphosphinate, zinc dimethylphosphinate, calcium ethylmethylphosphinate, ethylmethylphosphine. Magnesium oxide, aluminum ethylmethylphosphinate, zinc ethylmethylphosphinate, calcium diethylphosphinate, magnesium diethylphosphinate, aluminum diethylphosphinate, zinc diethylphosphinate, calcium methyl-n-propylphosphinate, methyl-n-propylphosphine Magnesium acetate, aluminum methyl-n-propylphosphinate, zinc methyl-n-propylphosphinate, calcium methylphenylphosphinate Arm, magnesium methylphenyl phosphinate, aluminum methylphenyl phosphinate, methyl phenyl phosphinate, zinc, calcium diphenyl phosphinate, magnesium diphenyl phosphinate, aluminum diphenyl phosphinic acid, diphenyl phosphinic acid zinc. Of these, aluminum diethylphosphinate and zinc diethylphosphinate are preferable, and aluminum diethylphosphinate is more preferable because of excellent balance between flame retardancy and electrical characteristics.

  Moreover, as diphosphinic acid used for manufacture of a diphosphinic acid salt, methandi (methylphosphinic acid) and benzene-1,4-di (methylphosphinic acid) are mentioned, for example.

  Specific examples of the diphosphinic acid salt represented by the general formula (II) include, for example, calcium methanedi (methylphosphinate), methanedi (methylphosphinic acid) magnesium, methanedi (methylphosphinic acid) aluminum, and methanedi (methylphosphinic acid). ) Zinc, benzene-1,4-di (methylphosphinic acid) calcium, benzene-1,4-di (methylphosphinic acid) magnesium, benzene-1,4-di (methylphosphinic acid) aluminum, benzene-1,4 -Di (methylphosphinic acid) zinc. Among these, methanedi (methylphosphinic acid) aluminum and methanedi (methylphosphinic acid) zinc are preferable because of excellent balance between flame retardancy and electrical characteristics.

  Specific products of phosphinic acid metal salts include, for example, “Exolit OP1230”, “Exolit OP1240”, “Exolit OP1312”, “Exolit OP1314”, and “Exolit OP1400” manufactured by Clariant.

  Examples of the nitrogen-based flame retardant include melamine compounds, cyanuric acid or isocyanuric acid and melamine compounds. Specific examples of melamine compounds include melamine, melamine derivatives, compounds having a structure similar to melamine, condensates of melamine, and the like. Specifically, melamine, ammelide, ammelin, formoguanamine, guanylmelamine, cyano Examples thereof include compounds having a triazine skeleton such as melamine, benzoguanamine, acetoguanamine, succinoguanamine, melam, melem, methone and melon, and sulfates and melamine resins thereof. The salt of cyanuric acid or isocyanuric acid and a melamine compound is an equimolar reaction product of cyanuric acid or isocyanuric acid and a melamine compound.

Examples of the nitrogen-phosphorus flame retardant include adducts (melamine adducts) and phosphazene compounds formed from melamine or a condensation product thereof and a phosphorus compound.
Examples of the phosphorus compound constituting the melamine adduct include phosphoric acid, orthophosphoric acid, phosphonic acid, phosphinic acid, metaphosphoric acid, pyrophosphoric acid, triphosphoric acid, tetraphosphoric acid, and polyphosphoric acid. Specific examples of the melamine adduct include melamine phosphate, melamine pyrophosphate, dimelamine pyrophosphate, melamine polyphosphate, melem polyphosphate, and melam polyphosphate, among which melamine polyphosphate is preferable. The number of phosphorus is preferably 2 or more, and more preferably 10 or more.
Specific products of the phosphazene compound include, for example, “Ravitor FP-100”, “Ravitor FP-110” manufactured by Fushimi Pharmaceutical Co., Ltd., “SPS-100”, “SPB-100” manufactured by Otsuka Chemical Co., Ltd. .

  Examples of inorganic flame retardants include metal hydroxides such as magnesium hydroxide and calcium hydroxide, phosphates such as zinc borate and aluminum phosphate, phosphites such as aluminum phosphite, and calcium hypophosphite. And hypophosphites such as calcium aluminate. These inorganic flame retardants may be blended for either the purpose of improving flame retardancy or reducing metal corrosivity.

  Examples of halogen flame retardants include hexabromocyclododecane, bis (dibromopropyl) tetrabromo-bisphenol A, bis (dibromopropyl) tetrabromo-bisphenol S, tris (dibromopropyl) isocyanurate, tris (tribromoneopentyl) phosphate. , Decabromodiphenylene oxide, brominated epoxy resin, bis (pentabromophenyl) ethane, tris (tribromophenoxy) triazine, ethylenebis (tetrabromophthal) imide, ethylenebispentabromophenyl, polybromophenylindane, brominated Examples thereof include polystyrene, tetrabromobisphenol A polycarbonate, brominated polyphenylene oxide, and polypentabromobenzyl acrylate. Among these, ethylene bis (tetrabromophthal) imide, brominated epoxy resin, and brominated polystyrene that can withstand processing at high temperatures are preferable, and brominated polystyrene is more preferable. These may be used alone or in combination.

  Although content of the flame retardant (B) in the resin composition of this invention is not specifically limited, In order to implement | achieve sufficient flame retardance, it is preferable that it is 5-30 mass%, and is 10-25 mass%. It is more preferable. When the content of the flame retardant (B) is less than 5% by mass, it is difficult to impart necessary flame retardancy to the resin composition. On the other hand, if the content of the flame retardant (B) exceeds 30% by mass, the resin composition is excellent in flame retardancy, but the metal corrosivity increases and melt kneading may be difficult. The resulting molded body may have insufficient mechanical properties.

  The polyamide resin composition of the present invention further contains a fibrous reinforcing material (C). The fibrous reinforcing material (C) is not particularly limited. For example, glass fiber, carbon fiber, boron fiber, asbestos fiber, polyvinyl alcohol fiber, polyester fiber, acrylic fiber, wholly aromatic polyamide fiber, polybenzoxazole fiber, Polytetrafluoroethylene 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, basalt fiber Can be mentioned. Among these, glass fiber, carbon fiber, and metal fiber are preferable because they have a high effect of improving mechanical properties, have heat resistance that can withstand the heating temperature during melt kneading with polyamide, and are easily available. The fibrous reinforcing material may be used alone or in combination.

  The glass fiber and the carbon fiber are preferably surface-treated with a silane coupling agent. The silane coupling agent may be dispersed in the sizing agent. Examples of the silane coupling agent include vinyl silanes, acrylic silanes, epoxy silanes, and amino silanes. Among them, since the adhesion effect between polyamide and glass fibers or carbon fibers is high, amino silane coupling agents are used. preferable.

The fiber length and fiber diameter of the fibrous reinforcing material are not particularly limited, but the fiber length is preferably 0.1 to 7 mm, and more preferably 0.5 to 6 mm. When the fiber length of the fibrous reinforcing material is 0.1 to 7 mm, the resin composition can be reinforced without adversely affecting the moldability. The fiber diameter is preferably 3 to 20 μm, and more preferably 5 to 13 μm. When the fiber diameter 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 include a circular shape, a rectangular shape, an elliptical shape, and other irregular cross-sections. A circular shape is preferable among them.

  Although content of the fibrous reinforcement (C) in the resin composition of this invention is not specifically limited, In order to implement | achieve sufficient mechanical strength, it is preferable that it is 5-60 mass%, and 10-50 mass%. It is more preferable that it is 20-40 mass%. When the content of the fibrous reinforcing material (C) is less than 5% by mass, the resin composition may have a small effect of improving mechanical properties. On the other hand, when the content of the fibrous reinforcing material (C) exceeds 60% by mass, the resin composition is saturated with the improvement effect of the mechanical properties, and not only the improvement effect can be expected, but also the fluidity. Since it falls extremely, it may become difficult to obtain a molded object.

The polyamide resin composition of the present invention can be further improved in stability and moldability by containing a phosphorus-based antioxidant.
The phosphorus-based 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, manganese phosphite, Phenyl phosphite, trioctadecyl phosphite, tridecyl phosphite, trinonyl phenyl phosphite, diphenyl isodecyl phosphite, bis (2,6-di-tert-butyl-4-methylphenyl) pentaerythritol diphosphite (" ADEKA STAB PEP-36 "), bis (2,4-di-tert-butylphenyl) pentaerythritol diphosphite (" ADEKA STAB PEP-24G "), tris (2,4-di-tert-butylphenyl) phosphite, Distearyl pentaerythritol Phosphite (“Adekastab PEP-8”), bis (nonylphenyl) pentaerythritol diphosphite (“Adekastab PEP-4C”), 1,1′-biphenyl-4,4′-diylbis [bisphosphonite (2 , 4-di-tert-butylphenyl)], tetrakis (2,4-di-tert-butylphenyl) 4,4'-biphenylene-di-phosphonite ("Hostanox P-EPQ"), tetra (tridecyl-4 , 4'-isopropylidene diphenyl diphosphite, 2,2-methylenebis (4,6-di-tert-butylphenyl) octyl phosphite, etc. Phosphorous antioxidant is used alone. It may be used in combination.
The phosphorus-based antioxidant is easily mixed uniformly with the phosphinic acid metal salt and prevents decomposition, so that flame retardancy can be improved. In addition, the phosphorus-based antioxidant can prevent the polyamide (A1) or polyamide (A2) from being decomposed or decrease in molecular weight, and can improve operability, moldability, and mechanical properties during melt processing.

  Other additives (D) such as other stabilizers, colorants, antistatic agents, carbonization inhibitors, and flame retardant aids may be further added to the polyamide resin composition of the present invention as necessary. Examples of the colorant include pigments such as titanium oxide, zinc oxide, and carbon black, and dyes such as nigrosine. Examples of the stabilizer include hindered phenol-based antioxidants, sulfur-based antioxidants, light stabilizers, heat stabilizers composed of copper compounds, and heat stabilizers composed of alcohols. The carbonization inhibitor is an additive that improves tracking resistance, and examples thereof include inorganic substances such as metal hydroxides and metal borate salts, and the above heat stabilizers. Examples of the flame retardant aid include antimony trioxide.

  The method for producing the resin composition of the present invention is not particularly limited, but polyamide (A1), polyamide (A2), flame retardant (B), fibrous reinforcing material (C) and other additions added as necessary A method of blending an agent and the like and melt-kneading is preferable. Examples of the melt-kneading method include a method using a batch kneader such as Brabender, a Banbury mixer, a Henschel mixer, a helical rotor, a roll, a single screw extruder, a twin screw extruder and the like. The melt kneading temperature is selected from a region where the polyamide (A1) and the polyamide (A2) melt and do not decompose. If the melt kneading temperature is too high, not only the polyamide (A1) or polyamide (A2) is decomposed, but also the flame retardant (B) may be decomposed. Therefore, when the melting point of the polyamide (A1) is Tm, It is preferable that it is (Tm-20 degreeC)-(Tm + 50 degreeC).

  As a method of processing the polyamide resin composition of the present invention into various shapes, a method of extruding the molten mixture into a strand shape to form a pellet, a method of hot-cutting the molten mixture, underwater cutting to form a pellet, Examples include a method of extrusion cutting into a sheet shape, and a method of extrusion pulverization into a block shape to form a powder.

The molded body of the present invention is formed by molding the 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, and an injection molding method is preferable because of its great effect of improving mechanical properties and moldability.
The injection molding machine is not particularly limited, and examples thereof include a screw inline type injection molding machine and a plunger type injection molding machine. The polyamide resin composition heated and melted in the cylinder of the injection molding machine is weighed for each shot, injected into the mold in a molten state, cooled to a predetermined shape and solidified, and then as a molded body from the mold. It is taken out. The resin temperature during injection molding is preferably heated and melted at a melting point (Tm) or higher of the polyamide (A1), and more preferably less than (Tm + 50 ° C.).
In addition, when the polyamide resin composition is heated and melted, it is preferable to use sufficiently dried polyamide resin composition pellets. If the water content is large, the resin foams in the cylinder of the injection molding machine, and it may be difficult to obtain an optimal molded body. The moisture content of the polyamide resin composition pellets used for injection molding is preferably less than 0.3 parts by mass and more preferably less than 0.1 parts by mass with respect to 100 parts by mass of the polyamide resin composition.

The polyamide resin composition of the present invention is excellent in reflow heat resistance and flame retardancy, has high fluidity, and can be molded while suppressing metal corrosiveness. It can be used for a wide range of applications such as electronic parts, miscellaneous goods, industrial equipment parts, civil engineering and building supplies.
Examples of automobile parts include a thermostat member, an IGBT module member of an inverter, an insulator, a motor insulator, an exhaust finisher, a power device housing, an ECU housing, a motor member, a coil member, a cable covering material, an in-vehicle camera housing, Automotive camera lens holder, automotive connector, engine mount, intercooler, bearing retainer, oil seal ring, chain cover, ball joint, chain tensioner, starter gear, reducer gear, automotive lithium-ion battery tray, automotive high-voltage fuse Housing, automotive turbocharger impeller.
Examples of electrical / electronic components include connectors, ECU connectors, Meitenlock connectors, modular jacks, reflectors, LED reflectors, switches, sensors, sockets, pin sockets, capacitors, jacks, fuse holders, relays, coil bobbins, breakers, circuits Parts, electromagnetic switches, holders, covers, plugs, casing parts for electrical and electronic devices such as portable PCs, impellers, vacuum cleaner impellers, resistors, variable resistors, ICs, LED casings, camera casings, Camera barrel, camera lens holder, tact switch, lighting tact switch, curling iron case, curling iron comb, all-mold direct current small switch, organic EL display switch, 3D printer material, motor bond magnet material Is mentioned.
Examples of miscellaneous goods include trays, sheets, and binding bands.
Examples of the industrial equipment parts include insulators, connectors, gears, switches, sensors, impellers, and plarail chains.
Examples of the civil engineering and building supplies include fences, storage boxes, construction switchboards, anchor bolt guides, anchor rivets, and solar cell panel raising materials.
Especially, since the polyamide resin composition of this invention is excellent in a flame retardance, it can be used suitably for an electrical / electronic component.

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

1. Measuring method The physical properties of the polyamide and the polyamide resin composition were measured by the following methods.

(1) Melting point Using a differential scanning calorimeter (DSC-7, manufactured by PerkinElmer Co., Ltd.), the temperature was raised to 350 ° C. at a temperature rising rate of 20 ° C./min, then held at 350 ° C. for 5 minutes, and the temperature falling rate was 20 ° C./min. The temperature was lowered to 25 ° C., held at 25 ° C. for 5 minutes, and the top of the endothermic peak when the temperature was measured again at a temperature rising rate of 20 ° C./min was defined as the melting point (Tm).

(2) Flowability The polyamide resin composition is set to 330 ° C. and mold temperature to 140 ° C. using an injection molding machine (ROBOSHOT S2000i manufactured by FANUC), with a clamping force of 100 tons and an injection pressure of 80 MPa. Then, under the conditions of an injection speed of 120 mm / second and an injection time of 5 seconds, molding was performed by attaching a dedicated metal mold with one-point gate on one side to the tip of the cylinder, and the bar flow flow length was measured. The dedicated mold has a shape in which an L-shaped molded body having a thickness of 0.2 mm and a width of 20 mm can be collected, has a gate at the upper center of the L-shape, and has a maximum flow length of 150 mm. In the present invention, the bar flow length is preferably 15 mm or more.

(3) Reflow heat resistance The polyamide resin composition was injection molded under the conditions of a cylinder temperature of 330 ° C. and a mold temperature of 140 ° C. using an injection molding machine (J35AD manufactured by Nippon Steel Works), and was 20 mm × 20 mm × 0.00 mm. A 5 mm test piece was prepared.
The obtained specimen was subjected to moisture absorption treatment at 85 ° C. × 85% RH for 168 hours, then heated in an infrared heating type reflow oven at 150 ° C. for 1 minute, and 265 at a rate of 100 ° C./min. The temperature was raised to 0 ° C. and held for 10 seconds.
○ when there is no change in the appearance of the test piece, △ when there are 1 to 2 blisters (blister) on the test piece, 3 or more blisters on the test piece, or the test piece is melted The case was evaluated as x.

(4) Flame retardance The polyamide resin composition was injection molded under the condition of a mold temperature of 170 ° C. using an injection molding machine (J35AD manufactured by Nippon Steel Works), 5 inches (127 mm) × 1/2 inch ( A test piece of 12.7 mm) × 1/127 inch (0.2 mm) was produced. At that time, the cylinder temperature was set to the molding processing temperature shown in Table 3, which is the lower limit temperature at which the test piece can be molded in each Example and Comparative Example.
Using the obtained test piece, flame retardancy was evaluated according to the standards of UL94 (standard defined by Under Writers Laboratories Inc., USA) shown in Table 1. In addition, when not corresponding to any of “V-0”, “V-1”, and “V-2”, “not” was indicated. A shorter total afterflame time indicates better flame retardancy.

(5) Metal corrosiveness As shown in FIG. 1, a metal plate (MP) (material) used as a steel material for a normal extruder, with a die (D) attached to a twin-screw kneading extruder (EX) (Ikegai PCM30) SUS630, 20 × 10 mm, thickness 5 mm, mass 7.8 g) was mounted on the top and bottom of the molten resin flow path (R), and a 1 mm gap was provided so that the molten resin was in contact over a width of 10 mm and a length of 20 mm. . A total of 25 kg of the polyamide resin composition was extruded under a discharge rate of 7 kg / h. At this time, the barrel temperature was set to the same temperature as the molding temperature in Table 3 set in (4) Preparation of flame retardant test piece.
After the extrusion, the metal plate (MP) was removed, left in a furnace at 500 ° C. for 10 hours, the adhered resin was removed, the mass was measured, and the metal corrosivity was evaluated by the change in mass before and after extrusion. It shows that metal corrosivity is so low that a mass change is small. In the present invention, the mass change rate is preferably 0.3% or less.

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

(1) Polyamide / Polyamide (A1-1)
4.70 kg of powdered terephthalic acid (TPA) as a 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, The reactor was placed in a ribbon blender reactor and heated to 170 ° C. with stirring at a rotation speed of 30 rpm under nitrogen sealing. Thereafter, while maintaining the temperature at 170 ° C. and maintaining the rotation speed at 30 rpm, 2.98 kg of 1,10-decanediamine (DDA) 4.98 kg heated to 100 ° C. as a diamine component using a liquid injection device Added continuously over 5 hours (continuous liquid injection method) to obtain a reaction product. The molar ratio of raw material monomers was TPA: DDA: STA = 48.5: 49.6: 1.9 (the equivalent ratio of functional groups of the raw material monomers was TPA: DDA: STA = 49.0: 50.0). : 1.0).
Subsequently, the obtained reaction product was polymerized by heating at 250 ° C. and a rotation speed of 30 rpm for 8 hours under a nitrogen stream in the same reaction apparatus to produce a polyamide powder.
Thereafter, the obtained polyamide powder was made into a strand using a biaxial kneader, the strand was cooled and solidified through a water tank, and was cut with a pelletizer to obtain polyamide (A1-1) pellets.

Polyamide (A1-2) to (A1-12), polyamide (A2-2)
Polyamides (A1-2) to (A1-12) and polyamide (A2-2) were obtained in the same manner as polyamide (A1-1) except that the resin composition was changed as shown in Table 2.

・ Polyamide (A2-1)
Polyamide 66 (Leona 1200 manufactured by Asahi Kasei Chemicals Corporation) was used as the polyamide (A2-1).

  Table 2 shows the resin composition and characteristic values of the polyamide.

(2) Flame retardant (B)
-B-1: Aluminum diethylphosphinate (Exolit OP1230 manufactured by Clariant)
-B-2: Hexaphenoxycyclotriphosphazene (Ravitor FP-100 manufactured by Fushimi Pharmaceutical Co., Ltd.)
B-3: Brominated polystyrene (Chemchula Great Lakes PDBS-80)

(3) Fibrous reinforcement (C)
・ Glass fiber (03JAFT692, manufactured by Asahi Fiberglass Co., average fiber diameter 10 μm, average fiber length 3 mm)

(4) Other additives (D)
・ Antimony trioxide (PATOX-M manufactured by Nippon Seiko Co., Ltd.)

Example 1
24.5 parts by mass of polyamide (A1-1), 25.5 parts by mass of polyamide (A2-1), and 20 parts by mass of flame retardant (B-1) are dry blended, and a loss-in-weight continuous quantitative supply device (KUBOTA) Manufactured by CE-W-1 type) and supplied to the main supply port of the same-direction twin screw extruder (TEM26SS type manufactured by Toshiba Machine Co., Ltd.) with a screw diameter of 26 mm and L / D50, and melt kneaded. . In the middle, 30 parts by mass of the fibrous reinforcing material (C) was supplied from the side feeder and further kneaded. After taking the strand from the die, it was cooled and solidified by passing through a water tank, and cut with a pelletizer to obtain polyamide resin composition pellets. The barrel temperature of the extruder was set to (melting point -5 to + 15 ° C), screw rotation speed 250 rpm, and discharge rate 25 kg / h.

Examples 2-17, Comparative Examples 1-7
Except having changed the composition of the polyamide resin composition as shown in Table 3, the same operation as in Example 1 was performed to obtain polyamide resin composition pellets.

  Various evaluation tests were performed using the obtained polyamide resin composition pellets. The results are shown in Table 3.

  The resin compositions of Examples 1 to 17 were excellent in fluidity, reflow heat resistance, flame retardancy, and low metal corrosivity in order to satisfy the requirements of the present invention. In particular, since the resin compositions of Examples 2 and 3 had the optimum polyamide (A1) content, both the fluidity and the reflow heat resistance were compatible at a high level.

Since the resin composition of Comparative Example 1 did not contain any polyamide (A2), and since the resin compositions of Comparative Examples 2 and 3 had an excessive content of polyamide (A1), both had fluidity. Inferior, in the fluidity test, the resin solidified before passing through the gate of the bar flow mold, and the flow length could not be measured. In addition, these resin compositions have to have a high molding processing temperature, have a long total after-flame time, and have high metal corrosivity.
On the other hand, the resin composition of Comparative Example 4 had a low reflow heat resistance because the polyamide (A2) content was excessive.
The resin composition of Comparative Example 5 contained a polyamide whose dicarboxylic acid component was terephthalic acid, but its melting point was less than 270 ° C., resulting in low reflow heat resistance.
Since the resin composition of Comparative Example 6 did not contain the flame retardant (B), it was poor in flame retardancy.
Since the resin composition of Comparative Example 7 did not contain the fibrous reinforcing material (C), it was determined as V-2 by falling cotton ignition of the afterflame portion in the flame retardant test.

EX: twin-screw kneading extruder D: die MP: metal plate R: flow path of molten resin

Claims (6)

A polyamide resin composition comprising polyamide (A1), polyamide (A2), flame retardant (B), and fibrous reinforcement (C),
The polyamide (A1) contains a dicarboxylic acid component containing terephthalic acid (TPA) and a diamine component, and has a melting point of 270 ° C. or higher.
The polyamide (A2) has a melting point of less than 270 ° C.,
The polyamide resin composition, wherein the content of the polyamide (A1) is 30% by mass or more and less than 50% by mass with respect to the total content of (A1) and (A2).   The polyamide resin composition according to claim 1, wherein the flame retardant (B) is a non-halogen flame retardant. The polyamide resin composition according to claim 1, wherein the flame retardant (B) is a compound represented by the following general formula (I) or (II).
(In the formula, R ¹ , R ² , R ⁴ and R ⁵ each independently represents a linear or branched alkyl group having 1 to 16 carbon atoms or a phenyl group. R ³ is linear or branched. The chain represents an alkylene group having 1 to 10 carbon atoms, an arylene group having 6 to 10 carbon atoms, an arylalkylene group, or an alkylarylene group, and M represents a calcium ion, an aluminum ion, a magnesium ion, or a zinc ion. Is 2 or 3. n, a, and b are integers satisfying the relational expression 2 × b = n × a.)   The dicarboxylic acid component of the polyamide (A1) further contains isophthalic acid (IPA), and the mass ratio of terephthalic acid to isophthalic acid (TPA / IPA) is 99.9 / 0.1 to 95/5. The polyamide resin composition according to any one of claims 1 to 3.   The polyamide (A1) includes a monocarboxylic acid component having a molecular weight of 140 or more, and the content of the monocarboxylic acid component is 0.3 to 4.0 mol% with respect to all monomer components constituting the polyamide (A1). It exists, The polyamide resin composition in any one of Claims 1-4 characterized by the above-mentioned.   A molded article obtained by molding the polyamide resin composition according to any one of claims 1 to 5.