TW201835219A - Polyamide resin composition, method for producing the same, and molded article made thereof - Google Patents

Abstract

An objective of the present invention is to provide a polyamide resin composition comprising: 100 parts by mass of a polyamide (A) having a melting point of 270 to 350 DEG C and 10 to 80 parts by mass of a phosphorus-based flame retardant (B), and has a yellowness index (YI0) of 3.0 or less.

Description

 Polyamide resin composition, method for producing the same, and molded body formed by the composition  

The present invention relates to a polyamide resin composition, a method for producing the same, and a molded body formed from the composition.

Polyamide has excellent heat resistance and mechanical properties, and is used as a constituent material of many motor/electronic parts and engine peripheral parts of automobiles.

Among these parts, polyamine which constitutes a motor/electronic part is required to have high flame retardancy. As a method of imparting flame retardancy to a resin, a flame retardant is usually used. In recent years, since environmental awareness has been increased, it is generally avoided to use a halogen-based flame retardant and a non-halogen flame retardant.

As a non-halogen flame retardant, for example, Patent Document 1 discloses a mixture of a reaction product of melamine and phosphoric acid, a zinc compound, and a phosphinate; and Patent Document 2 discloses a reaction product of melamine and phosphoric acid, a phosphinate. And a mixture of metal compounds; either of them reveals that the molded article at 1/16 inch meets the flame retardant specification UL94V-0.

However, the phosphinate may be decomposed when it is melt-kneaded with polyamine to produce a resin composition. Due to the gas generated at this time, the polyamine is also decomposed and the molecular weight of the polyamide is lowered. The obtained resin composition has problems of reduction in heat resistance, mechanical properties, flame retardancy, and the like, and thermal polychromism and yellowness (yellowness index, YI) rise due to thermal deterioration and oxidative degradation of polyamide. .

 [Previous Technical Literature]    [Patent Literature]  

[Patent Document 1] Japanese Patent Laid-Open Publication No. 2004-263188

[Patent Document 2] Japanese Patent Laid-Open Publication No. 2007-023206

The present invention has been made to solve the above problems, and an object of the invention is to provide a polyamide resin composition which has excellent heat resistance, mechanical properties, and flame retardancy while suppressing an increase in yellowness.

In order to solve the above problems, the inventors of the present invention have conducted intensive studies and found that the polyamide resin composition produced under specific conditions can solve the above problems, and the present invention has been completed.

That is, the gist of the present invention is as follows.

(1) A polyamide resin composition comprising 100 parts by mass of polyamine (A) having a melting point of 270 to 350 ° C, 10 to 80 parts by mass of a phosphorus-based flame retardant (B), and yellowness (YI ₀ ) is 3.0 or less.

(2) The polyamide resin composition according to (1), wherein the yellowness change value (ΔYI) after the reflow treatment at 265 ° C is 12.0 or less.

(3) The polyamide resin composition according to (1) or (2), wherein the phosphorus-based flame retardant (B) is a phosphinate and/or a diphosphinate.

(4) The polyamine resin composition according to (3), wherein the phosphinate is a compound represented by the following formula (I), and the diphosphinate is represented by the following formula (II) Compound, (wherein R ¹ , R ² , R ⁴ and R ⁵ are each independently and represent a C 1 to 16 alkyl group or a phenyl group of a straight or branched chain. R ³ means a straight or branched chain An alkyl group having 1 to 10 carbon atoms, an extended aryl group having 6 to 10 carbon atoms, an alkylalkyl group or an alkyl aryl group. M represents a calcium ion, an aluminum ion, a magnesium ion or a zinc ion, and m is 1 or 3. n, a, and b are integers satisfying the relationship of 2 × b = n × a).

(5) The polyamide resin composition according to any one of (1) to (4) further comprising 5 to 140 parts by mass of the fibrous reinforcing material (C).

(6) The polyamide resin composition according to any one of (1) to (5) further comprising 0.1 to 20 parts by mass of talc (F).

(7) A method for producing a polyamidamide resin composition according to any one of the above (1) to (6), wherein A) In the melt-kneading with the phosphorus-based flame retardant (B), one or more side feeders are provided in the melt kneading machine, and each side is 100 parts by mass with respect to the polyamide (A). A phosphorus-based flame retardant (B) is added from a side feeder so that the amount of the phosphorus-based flame retardant (B) to be added to the feeder is 20 parts by mass or less.

(8) A method for producing a polyamine resin composition, which is a method for producing the polyamine resin composition according to (5) above, wherein in the melt-kneading of the resin composition, the fiber is in a fibrous form The reinforcing material (C) is added in plural times.

(9) The method for producing a polyamide resin composition according to (7) or (8), wherein the polyamine (A) is polymerized before melt-kneading, and the polymerization is carried out under an inert gas atmosphere. .

(10) The method for producing a polyamide resin composition according to any one of (7) to (9), wherein the polyamine (A) and the phosphorus-based flame retardant are carried out under an inert gas atmosphere ( B) Melt mixing.

(11) A molded article obtained by molding the polyamidamide resin composition according to any one of the above items (1) to (6).

According to the present invention, it is possible to provide a polyamide resin which can greatly suppress thermal discoloration due to thermal deterioration and oxidative degradation during melt kneading, and can suppress decomposition of polyamide and can maintain mechanical properties and flame retardancy to a high degree. Composition. Further, the molded body obtained by molding the polyamide resin composition of the present invention can suppress an increase in yellowness even when a reflow treatment at a maximum temperature of about 260 ° C is performed.

Hereinafter, the present invention will be described in detail.

The polyamine resin composition of the present invention contains polyamine (A) and a phosphorus-based flame retardant (B).

The polyamine (A) constituting the polyamine resin composition of the present invention has a melting point of 270 ° C to 350 ° C. The polyamidamine (A) has a heat resistance and can withstand a reflux step of a maximum temperature of about 260 ° C by a melting point of 270 ° C or higher. On the other hand, when the melting point of the polyamine (A) exceeds 350 ° C, since the decomposition temperature of the guanamine bond is about 350 ° C, carbonization and decomposition may occur during melt processing.

The polyamine (A) is an aliphatic polyamine, a semi-aromatic polyamine, an alicyclic polyamine, or a copolymer thereof, in terms of classification of a monomer component.

Specific examples of the aliphatic polyamines include polyamine 46 and the like.

The semi-aromatic polyamine is a polyamine which is composed of an aromatic dicarboxylic acid component and an aliphatic diamine component, and specific examples thereof include polyamine 4I (I: isophthalic acid) ), polyamine 6I, polyamine 7T (T: terephthalic acid), polyamine 8T, polyamine 9T, polyamine 10T, polyamine 11T, polyamine 12T, and the like.

Specific examples of the alicyclic polyamines include polyamine 6C (C: 1,4-cyclohexanedicarboxylic acid), polyamido 7C, polyamine 8C, polyamine 9C, and poly Guanamine 10C, polyamido 11C, polyamido 12C, and the like.

Further, as the copolymer, for example, when the carbon number of the diamine is 6, PA6T/6, PA6T/12, PA6T/66, PA6T/610, PA6T/612, PA6T/6I, PA6T/6I/66 are mentioned. , PA6T/M5T (M5: methylpentanediamine), PA6T/TM6T (TM6: 2, 2,4- or 2,4,4-trimethylhexamethylenediamine), PA6T/MMCT (MMC: 4 , 4'-methylenebis(2-methylcyclohexylamine)) and the like.

As the polyamine (A), these polyamines may be used singly, and a copolymer or a mixture of two or more kinds of polyamines may be used.

In the present invention, polyamido 46, polyamine 6T, polyamidamine 9T, polydecylamine 10T, and the like are high in industrial versatility, and may be exemplified as polyamine (A). A preferred example. Further, from the viewpoint of high heat resistance and low water absorption, since it has particularly excellent reflow resistance, it is more preferable to use polyamide 9T, polyamine 9T, polyamine 10T, and the like. Among them, polyamine 10T and copolymers thereof are particularly preferred.

In the present invention, the polyamine (A) is preferably a monocarboxylic acid component as a constituent component. By containing a monocarboxylic acid, the polyamine (A) can maintain a low amount of terminal free amine groups, and it is possible to suppress decomposition and discoloration of polyamine caused by thermal deterioration and oxidative degradation upon heating. As a result, there is an effect that the mechanical properties and the flame retardancy can be highly maintained.

The content of the monocarboxylic acid component is preferably from 0.3 to 4.0 mol%, more preferably from 0.3 to 3.0 mol%, and from 0.3 to 2.5 mol%, based on the total monomer component constituting the polyamine (A). For better, it is particularly good at 0.8 to 2.5 mol%. By containing a monocarboxylic acid component in the above range, the polyamine (A) can suppress decomposition and discoloration due to thermal deterioration and oxidative degradation during heating, and can reduce the molecular weight distribution during polymerization and can be observed during molding. It is possible to suppress the amount of gas generated during the forming process by the improvement of the mold release property. On the other hand, when the content of the monocarboxylic acid component of the polyamine (A) exceeds the above range, the mechanical properties may be lowered. Further, in the present invention, the content of the monocarboxylic acid means a ratio at which the residue of the monocarboxylic acid in the polyamine (A), that is, the terminal hydroxyl group is separated from the monocarboxylic acid.

In the present invention, the molecular weight of the monocarboxylic acid component is preferably 140 or more, more preferably 170 or more. When the molecular weight of the monocarboxylic acid of the polyamide (A) is 140 or more, it is possible to suppress decomposition and discoloration due to thermal deterioration and oxidative degradation upon heating, and to improve mold release property, and to suppress gas at a temperature at the time of forming processing. The amount of production, and can improve the forming fluidity.

The monocarboxylic acid component may, for example, be an aliphatic monocarboxylic acid, an alicyclic monocarboxylic acid or an aromatic monocarboxylic acid, and particularly preferably an aliphatic monocarboxylic acid.

Examples of the aliphatic monocarboxylic acid having a molecular weight of 140 or more include caprylic acid, capric acid, capric acid, lauric acid, myristic acid, palmitic acid, stearic acid, and behenic acid. Among them, because of the high versatility, especially stearic acid is preferred.

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 the like. Things.

The monocarboxylic acid component may be used singly or in combination. Further, a monocarboxylic acid having a molecular weight of 140 or more and a monocarboxylic acid having a molecular weight of less than 140 may be used in combination.

Further, in the present invention, the molecular weight of the monocarboxylic acid means the molecular weight of the monocarboxylic acid of the starting material.

Usually, a polymer has a crystal phase and an amorphous phase, and a crystal characteristic such as a melting point is known to be determined solely by the state of the crystal phase. Since the terminal group in the polymer exists in the amorphous phase, the melting point of the polyamine does not change due to the presence or absence of the terminal group and the kind. Further, since the monocarboxylic acid bonded to the terminal of the polyamide chain is also present in the amorphous phase, the melting point of the polyamine does not decrease due to the monocarboxylic acid.

In the present invention, the melt flow rate (MFR) of the polyamine (A) at 340 ° C and 1.2 kg load is preferably from 1 to 200 g/10 min, more preferably from 10 to 150 g/10 min, and from 20 to 100g/10 minutes is even better. MFR can be set as an index of forming fluidity, and a higher value of MFR means higher fluidity. When the MFR of the polyamine (A) exceeds 200 g/10 minutes, the mechanical properties of the obtained resin composition are lowered, and when the MFR of the polyamide (A) is less than 1 g/10 minutes, the fluidity is remarkable. The ground is low and there is a situation where it cannot be melt processed.

Polyamine (A) can be produced by a conventionally known method of a heating polymerization method and a solution polymerization method. Among them, in particular, industrially advantageous, a heating polymerization method can be suitably employed. The polymerization of the polyamine (A) is carried out by enclosing an inert gas such as nitrogen, carbon dioxide or argon into the polymerization vessel, and is preferably carried out under an inert gas atmosphere. Thereby, it is possible to suppress discoloration caused by oxidative degradation of polyamine in the polymerization, and also to suppress discoloration in the step after polymerization.

In the production of polyamine (A), a polymerization catalyst can also be used to increase the polymerization efficiency. Examples of the polymerization catalyst include phosphoric acid, phosphorous acid, hypophosphorous acid, or the like. Generally, the amount of the polymerization catalyst added is preferably 2 mol% or less based on the total molar amount of the dicarboxylic acid and the diamine. .

The phosphorus-based flame retardant (B) constituting the polyamine resin composition of the present invention may, for example, be a phosphate compound, a phosphinate, a diphosphinate or a phosphazene compound.

Examples of the phosphate compound include trimethyl phosphate, triethyl phosphate, tributyl phosphate, trioctyl phosphate, butoxyethyl phosphate, triphenyl phosphate, tricresyl phosphate, and toluene phosphate. Phenyl ester, octyl diphenyl phosphate, tris(2-ethylhexyl) phosphate, diisopropyl phenyl phosphate, tris(xylylene) phosphate, cis (isopropylphenyl) phosphate, phosphoric acid Naphthyl ester, bisphenol A diphosphate, hydroquinone diphosphate, resorcinol diphosphate, resorcinol-diphenyl phosphate, trioxybenzene triphosphate, or such substituents, condensates . Among them, a phosphate compound is preferable because it is not easily attached to a mold and the molded body has excellent heat resistance and moisture resistance. The phosphate compound can be a monomer, oligomer, polymer or a mixture of such. Specific examples of the phosphate ester compound include "TPP" [triphenyl phosphate], "TXP" [tris(xylene) phosphate], and "CR-733S" manufactured by Daeba Chemical Industry Co., Ltd. [ Resorcinol bis(diphenyl phosphate)], "PX200" [1,3-phenylene-fluorene (2,6-dimethylphenyl) phosphate], "PX201" [1,4-stretch Phenyl-fluorene (2,6-dimethylphenyl)phosphate], "PX202" [4,4'-extended biphenyl-fluorene (2,6-dimethylphenyl) phosphate]. These may be used alone or in combination.

Examples of the phosphinate and the diphosphinate include compounds represented by the following formula (I) and formula (II).

Wherein R ¹ , R ² , R ⁴ and R ⁵ are each independently and must be a linear or branched chain having from 1 to 16 carbon atoms or a phenyl group, an alkyl group having from 1 to 8 carbon atoms or Phenyl group is preferred, and methyl, ethyl, n-propyl, isopropyl, n-butyl, t-butyl, n-pentyl, n-octyl, phenyl are more preferred, and ethyl is more preferred. . R ¹ and R ² and R ⁴ and R ⁵ may also form a ring with each other.

R ³ must be a from 1 to 10 carbon alkyl group, a carbon number 6 to 10 aryl group, an alkyl alkyl group or an alkyl aryl group in a linear or branched chain. Examples of the alkylene group having 1 to 10 carbon atoms in the linear or branched chain include a methylene group, an exoethyl group, a n-propyl group, an exo-propyl group, an isopropylidene group, a n-butyl group, and the like. Tri-butyl, n-pentyl, octyl, and twelfth. Examples of the extended aryl group having 6 to 10 carbon atoms include a stretching phenyl group and a stretching naphthyl group. Examples of the alkyl extended aryl group include a methylphenylene group, an ethylphenylene group, a tert-butylphenylene group, a methylnaphthyl group, an ethylnaphthyl group, and a tert-butylnaphthyl group. Examples of the arylalkylene group include a phenylmethylene group, a phenylethyl group, a phenylpropyl group, and a phenylbutyl group.

The M system represents a metal ion. Examples of the metal ions include calcium ions, aluminum ions, magnesium ions, and zinc ions, and aluminum ions and zinc ions are preferred, and aluminum ions are more preferred.

m and n represent the valence of metal ions. m is 2 or 3. a indicates the number of metal ions, and b indicates the number of secondary phosphonate ions. n, a, and b are integers satisfying "2 × b = n × a".

The phosphinates and the diphosphinates are each produced in aqueous solution using the corresponding phosphinic acid and diphosphinate, metal carbonate, metal hydroxide or metal oxide, usually in a monomeric manner. Exist, but also in the form of a polymeric phosphinate having a degree of condensation of from 1 to 3 depending on the reaction conditions.

Examples of the phosphinic acid used in the production of the phosphinate include dimethylphosphinic acid, ethylmethylphosphinic acid, diethylphosphinic acid, and methyl-n-propylphosphinic acid. Isobutyl methylphosphinic acid, octylmethylphosphinic acid, methylphenylphosphinic acid, diphenylphosphinic acid, especially diethyl phosphinic acid.

Specific examples of the phosphinate represented by the above formula (I) include calcium dimethyl phosphinate, magnesium dimethyl phosphinate, aluminum dimethyl phosphinate, and dimethyl group. Zinc phosphonate, calcium ethylmethylphosphinate, magnesium ethylmethylphosphinate, aluminum ethylmethylphosphinate, zinc ethylmethylphosphinate, calcium diethylphosphinate, diethyl Magnesium phosphinate, aluminum diethylphosphinate, zinc diethylphosphinate, calcium methyl-n-propylphosphinate, magnesium methyl-n-propylphosphinate, methyl-n-propyl Aluminum phosphinate, zinc methyl-n-propylphosphinate, calcium methylphenylphosphinate, magnesium methylphenylphosphinate, aluminum methylphenylphosphinate, methylphenylphosphinic acid Zinc, calcium diphenylphosphinate, magnesium diphenylphosphinate, aluminum diphenylphosphinate, zinc diphenylphosphinate. Among them, in particular, since the balance between flame retardancy and electrical properties is excellent, aluminum diethylphosphinate and zinc diethylphosphinate are preferred, and aluminum diethylphosphinate is more preferred.

Further, examples of the diphosphonic acid used for producing the diphosphinate include methane bis(methylphosphinic acid) and benzene-1,4-bis(methylphosphinic acid).

Specific examples of the diphosphinate represented by the above formula (II) include methane bis(methylphosphinic acid) calcium, methane bis(methylphosphinic acid) magnesium, and methane di(methyl). Phosphonic acid) aluminum, methane bis(methylphosphinic acid) zinc, benzene-1,4-bis(methylphosphinic acid) calcium, benzene-1,4-bis(methylphosphinic acid) magnesium, benzene -1,4-bis(methylphosphinic acid) aluminum, benzene-1,4-bis(methylphosphinic acid) zinc. Among them, in particular, since the balance between flame retardancy and electrical properties is excellent, methane bis(methylphosphinic acid) aluminum or methane bis(methylphosphinic acid) zinc is preferred.

The phosphorus-based flame retardant (B) is preferably a phosphinate or a diphosphonate because it is excellent in miscibility with polyamine (A) and can be effectively imparted with a small amount of addition. Further, a mixture of a phosphinate or a diphosphonate is particularly preferred. Examples of the combination of the phosphinate and the diphosphinate include a phosphinate such as aluminum diethylphosphinate or zinc diethylphosphinate, and methane bis(methylphosphinic acid). A secondary phosphonate such as aluminum or methane bis(methylphosphinic acid) zinc. Specific examples of the phosphinic acid salt, the diphosphinic acid salt, and the mixture thereof include "Exolit OP1230", "Exolit OP1240", "Exolit OP1312", and "Exolit OP1314" manufactured by CLARIANT. "Exolit OP1400".

The phosphazene compound is, for example, a cyclic phosphazene compound represented by the following formula (III).

In the formula, R ⁶ and R ⁷ each independently represent an alkyl group having 1 to 10 carbon atoms, an aryl group having 6 to 15 carbon atoms, and c is an integer of 3 to 15. Examples of the alkyl group having 1 to 10 carbon atoms include a methyl group, an ethyl group, a n-propyl group, an isopropyl group, various butyl groups, various hexyl groups, various octyl groups, a cyclopentyl group, and a cyclohexyl group. R ⁶ and R ⁷ may be any of a linear chain, a branched chain, and a cyclic chain. In addition, examples of the aryl group having 6 to 15 carbon atoms include a phenyl group which may have a substituent such as an alkyl group, an aryl group or an alkoxy group introduced into the ring. R ⁶ and R ⁷ are all preferably an aryl group, and particularly preferably a phenyl group. Specific examples of the phosphazene compound include "Rabitle FP-100" manufactured by Fushimi Pharmaceutical Co., Ltd., "Rabitle FP-110", "SPS-100" manufactured by Otsuka Chemical Co., Ltd., and "SPB-100".

The phosphorus-based flame retardant (B) may also be used in combination with the flame retardant auxiliary (D). Examples of the flame retardant auxiliary (D) include a nitrogen-based flame retardant and an inorganic flame retardant, and among them, a nitrogen-based flame retardant is particularly preferable.

Examples of the nitrogen-based flame retardant include melamine cyanurate, melamine polyphosphate, melamine pyrophosphate, melamine phosphate, dimelamine pyrophosphate, melidyl polyphosphate, and melidyl polyphosphate, especially because The combination of a phosphinate and a diphosphonate is more effective, and melamine polyphosphate is preferred. The number of phosphorus is preferably 2 or more, more preferably 10. The ratio of the phosphinate and the diphosphinate to the melamine polyphosphate is preferably 1:1 to 8:1 in terms of mass ratio, more preferably 2:1 to 4:1.

Examples of the inorganic flame retardant include metal hydroxides such as magnesium hydroxide, calcium hydroxide, and calcium aluminate, and other zinc salts such as zinc borate and zinc phosphate. Among them, a mixture of two or more kinds of zinc borate and other zinc salts is preferred, and a mixture of magnesium hydroxide, zinc borate and zinc phosphate is more preferred.

As zinc borate, for example, 2ZnO can be mentioned. 3B ₂ O ₃ , 4ZnO. B ₂ O ₃ . H ₂ O, 2ZnO. 3B ₂ O ₃ . 3.5H ₂ O.

As another zinc salt, Zn ₃ (PO ₄ ) ₂ is mentioned, for example. Zinc phosphate such as ZnO, zinc stannate such as ZnSn(OH) ₆ or ZnSnO ₃ , and calcium zinc molybdate, especially zinc phosphate.

When the zinc borate and the zinc phosphate are used together, the ratio of the zinc borate to the zinc phosphate is preferably from 1:0.1 to 1:5, more preferably from 1:2 to 1:4, and the ratio of 1:1. 2.5 to 1:3.5 is even better.

The metal hydroxide may be in the form of a pellet, a plate or a needle. When a granule or a plate is used, the average particle diameter is preferably from 0.05 to 10 μm, more preferably from 0.1 to 5 μm. When the needle is used, the average diameter is preferably 0.01 to 10 μm, more preferably 0.1 to 5 μm, and the average length is preferably 5 to 2000 μm, more preferably 10 to 1000 μm. From the viewpoint of heat resistance, the content of other metals of metal hydroxides and impurities such as chlorine and sulfur is preferably as small. Further, since the dispersibility in the polyamide resin composition can be improved and the thermal stability is improved, the surface of the metal hydroxide is preferably surface-treated with a surface treatment agent, a solid solution or the like. Examples of the surface treatment agent include a decane coupling agent, a titanium coupling agent, a fatty acid, and a derivative thereof. Examples of the solid solution include metals such as nickel.

In the polyamide resin composition of the present invention, the flame retardant auxiliary (D) may be used singly or in combination.

In the polyamide resin composition, the content of the phosphorus-based flame retardant (B) must be 10 to 80 parts by mass, preferably 20 to 40 parts by mass, per 100 parts by mass of the polyamidamine (A). When the content of the phosphorus-based flame retardant (B) is less than 10 parts by mass, it is difficult to impart flame retardancy. On the other hand, when the content of the phosphorus-based flame retardant (B) exceeds 80 parts by mass, it is difficult to melt-knead the resin composition, and the obtained resin composition has excellent flame retardancy, but mechanical properties are instead It becomes insufficient.

The polyamine resin composition of the present invention can greatly suppress thermal discoloration due to thermal deterioration and oxidative degradation during melt kneading, and the yellowness (YI ₀ ) must be 3.0 or less, and -10.0 to - 1.0 is preferred, and -10.0 to -5.0 is more preferred. The polyamidamide resin composition capable of greatly suppressing thermal discoloration during melt kneading and having a yellowness (YI ₀ ) of 3.0 or less can be obtained by polyamine (A) and a phosphorus-based flame retardant as described later. In the melt-kneading of (B), the amount of the phosphorus-based flame retardant (B) added to the polyamine (A) is restricted and produced.

In addition, the molded article obtained by molding the polyamine resin composition of the present invention has excellent heat discoloration resistance, and can suppress the decomposition of polyamine by heating the molded body, so that the yellowing is suppressed. The yellowness change value (?YI) after the reflow treatment at 265 ° C is preferably 12.0 or less. When the yellowness change value (?YI) of the resin composition after the reflow treatment at 265 ° C is 12.0 or less, discoloration in the assembly step of the motor/electronic component can be suppressed.

The polyamide resin composition of the present invention preferably further contains a fibrous reinforcing material (C). The fibrous reinforcing material (C) is not particularly limited, and examples thereof include glass fiber, carbon fiber, boron fiber, asbestos fiber, polyvinyl alcohol fiber, polyester fiber, acrylic fiber, wholly aromatic polyamide fiber, and polyphenylene. Oxazole fiber, polytetrafluoroethylene fiber, kenaf fiber, bamboo fiber, hemp fiber, bagasse fiber, high strength polyethylene fiber, alumina fiber, tantalum carbide fiber, potassium titanate fiber, yellow Copper fiber, stainless steel fiber, steel fiber, ceramic fiber, basalt fiber, etc. Among them, glass fiber, carbon fiber, and metal fiber are preferred because of their high improvement in mechanical properties and heat resistance which can withstand the heating temperature at the time of melt kneading with a polyamide resin. The fibrous reinforcing material (C) may be used singly or in combination.

It is preferred that the glass fiber or the carbon fiber is surface-treated with a decane coupling agent. The decane coupling agent can also be dispersed in the sizing agent. Examples of the decane coupling agent include a vinyl decane type, a propylene decane type, an epoxy decane type, and an amino decane type, and particularly, since the adhesion effect with polyamine and glass fiber or carbon fiber is high, An amine decane coupling agent is preferred.

The fiber length and the fiber diameter of the fibrous reinforcing material are not particularly limited, and the fiber length is preferably 0.1 to 7 mm, more preferably 0.5 to 6 mm. The fiber-reinforced material has a fiber length of 0.1 to 7 mm, does not adversely affect the formability, and can reinforce the resin composition. Further, the fiber diameter is preferably 3 to 20 μm, more preferably 5 to 13 μm. The fibrous reinforcing material has a fiber diameter of 3 to 20 μm, is not broken during melt-kneading, and can reinforce the resin composition. Examples of the cross-sectional shape of the fibrous reinforcing material include a circular shape, a rectangular shape, an elliptical shape, and a different cross-sectional shape. Among them, a circular shape is preferable.

In the polyamide resin composition, the content of the fibrous reinforcing material (C) is preferably from 5 to 140 parts by mass, more preferably from 40 to 80 parts by mass, per 100 parts by mass of the polyamine (A). When the content of the fibrous reinforcing material is less than 10 parts by mass, the effect of improving mechanical properties may be small. On the other hand, when the content of the fibrous reinforcing material exceeds 140 parts by mass, the effect of improving the mechanical properties of the polyamide resin composition is saturated, and not only the further lifting effect cannot be expected, but also the workability at the time of melt kneading is lowered and it is difficult to obtain The case of a pellet.

The polyamidamide resin composition of the present invention is excellent in stability and moldability by containing a phosphorus-based antioxidant (E).

The phosphorus-based antioxidant may be either an inorganic compound or an organic compound. Examples of the phosphorus-based antioxidant include inorganic phosphate such as monosodium phosphate, disodium phosphate, trisodium phosphate, sodium phosphite, calcium phosphite, magnesium phosphite, and manganese phosphite, and triphenyl phosphite and phosphorous acid. Tris(octadecyl)ester, tridecyl phosphite, tridecylphenyl phosphite, diphenylisodecyl phosphite, bis(2,6-di-t-butyl-4-methylphenyl ) pentaerythritol diphosphite ("Adekastab PEP-36"), bis(2,4-di-t-butylphenyl) pentaerythritol diphosphite ("Adekastab PEP-24G"), Bisphosphonium phosphite (2,4-di-tert-butylphenyl) ester, distearyl pentaerythritol diphosphite ("Adekastab PEP-8"), bis(indolyl) pentaerythritol Diphosphite ("Adekastab PEP-4C"), 1,1'-biphenyl-4,4'-diylbis[phosphinic acid bis(2,4-di-tert-butylphenyl) ester ], 肆 (2,4-di-t-butylphenyl) 4,4'-Exbiphenyl-di-phosphinate ("HOSTANOX P-EPQ"), diphosphoric acid tetrakis An organophosphorus compound such as -4,4'-isopropylidene diphenyl ester or 2,2-methylenebisbis(4,6-di-t-butylphenyl)octyl phosphite. The phosphorus-based antioxidants may be used singly or in combination.

Since the phosphorus-based antioxidant (E) is easily blended with the phosphorus-based flame retardant (B) to prevent decomposition of the flame retardant, the flame retardancy can be improved. Further, it is possible to prevent the molecular weight of the polyamide (A) from being lowered and to improve workability, moldability, and mechanical properties during extrusion processing. In particular, a reduction in the degree of discoloration during the reflow treatment can exert a remarkable effect.

The content of the phosphorus-based antioxidant (E) is preferably 0.1 to 3 parts by mass, more preferably 0.1 to 1 part by mass, per 100 parts by mass of the polyamine (A). By setting the content of the phosphorus-based antioxidant (E) to 0.1 to 3 parts by mass, the stability, moldability, and mechanical properties during extrusion processing are not lowered, and the mold release property at the time of molding can be improved. And suppressing the clogging of the die vent hole, and improving the continuous injection formability.

The molded article obtained by molding the polyamidamine resin composition of the present invention can suppress the increase in yellowness even when the reflow treatment is carried out at a maximum temperature of about 260 ° C, and the phthalocyanine resin composition further contains talc ( F), generation of foaming at the time of reflow treatment can be suppressed. The talc (F) system is not particularly limited, and the average particle diameter is preferably 10 to 30 μm. Further, the talc (F) can be surface-treated with an organic compound such as a decane coupling agent, and the surface treatment can improve the adhesion to the polyamide (A), and has an effect of improving the strength and suppressing foaming. The average particle diameter of the talc (F) in the present invention means a median diameter (D50) obtained by a laser diffraction method.

The polyamidamide resin composition of the present invention may further contain other additives such as a filler and a stabilizer as needed. Examples of the additive include a filler such as a swelling clay mineral, cerium oxide, aluminum oxide, glass beads, and graphite, a pigment such as titanium oxide or carbon black, a hindered phenol antioxidant, a sulfur antioxidant, and a light stabilizer. Antistatic agent.

a method of producing a polyamine resin composition of the present invention by mixing a polyamine (A) with a phosphorus-based flame retardant (B) and further blending the fibrous reinforcing material (C) with other additives, etc., as long as it does not damage The effect is not particularly limited, but a melt-kneading method is preferred. As the melt-kneading method, a batch-type kneader such as Brabender, a banbury mixer, and a Henschel mixer can be used. , a spiral rotor, a roller, a single-axis extruder, a twin-screw extruder, and the like. The melt kneading temperature can be selected from a region where the polyamide resin is melted and does not decompose. When the kneading temperature is too high, not only the polyamidoamine (A) will decompose, but also the phosphorus-based flame retardant (B) may be decomposed, so that the melting point (Tm) of the polydecylamine (A) becomes (Tm- 20 ° C) to (Tm + 50 ° C) is preferred.

When the resin composition of the present invention is produced by melt-kneading, the amount of the phosphorus-based flame retardant (B) added to the polyamine (A) must be limited. When a large amount of the phosphorus-based flame retardant (B) is added to the polyamide (A) during the melt-kneading of the polyamide (A) and the phosphorus-based flame retardant (B), the temperature is temporarily impatient. When the viscosity of the resin composition is rapidly increased, it is subjected to a large shear force. As a result, the actual temperature of the resin composition is higher than the set temperature of the apparatus, and there is a fear that the organic components such as the phosphorus-based flame retardant (B) are decomposed and thermally discolored.

As a method of limiting the amount of the phosphorus-based flame retardant (B) to be supplied to the polyamide (A), for example, when a continuous melt kneader is used, one or more side feeders may be provided in the melt kneading machine. And a method of limiting the amount of addition of the phosphorus-based flame retardant (B) per one side feeder. In the present invention, the amount of the phosphorus-based flame retardant (B) to be added to the side feeder is required to be added from the side feeder so as to be 20 parts by mass or less based on 100 parts by mass of the polyamide (A). Phosphorus-based flame retardant (B).

Further, as a method of limiting the amount of the phosphorus-based flame retardant (B) to be supplied to the polyamide (A), when a batch type mixer is used as the melt kneading machine, a method of supplying the powder in plural times may be mentioned. The amount of the phosphorus-based flame retardant (B) per one time is preferably 20 parts by mass or less based on 100 parts by mass of the polyamine (A).

In the production of the resin composition containing the fibrous reinforcing material (C), it is preferable to add the fibrous reinforcing material (C) in a plurality of times during the melt-kneading of the resin composition, relative to the polyamide ( A) 100 parts by mass, and the amount of the fibrous reinforcing material (C) added per one time is preferably 30 parts by mass or less.

By limiting the amount of the phosphorus-based flame retardant (B) or the fibrous reinforcing material (C) to be supplied to the polyamide (A), the actual temperature of the resin composition can be prevented from excessively rising, and the melt-kneading can be suppressed. In the molded article obtained from the resin composition, discoloration due to thermal deterioration or oxidative degradation can be suppressed.

In the melt-kneading of the resin composition, it is preferable to encapsulate an inert gas such as nitrogen, carbon dioxide or argon from the raw material supply unit of the machine to the heating unit, and to perform melt-kneading in an inert gas atmosphere. Thereby, it is possible to suppress discoloration due to oxidative degradation of the organic component such as polyamine (A) and various surface treatment agents during melt kneading, and to suppress discoloration in the step after melt kneading.

As a method of processing the resin composition into various shapes, a method of extruding a molten mixture into a strand shape and forming a pellet shape is mentioned; the molten mixture is subjected to hot cutting and water cutting. A method of forming a pellet shape; a method of extruding into a sheet form and cutting; and extruding into a block shape and pulverizing to form a powder shape.

The molded article of the present invention is obtained by molding the polyamine resin composition of the present invention.

Examples of the method for forming the polyamide resin composition of the present invention include an injection molding method, an extrusion molding method, a blow molding method, and a calcination molding method, and the mechanical properties and the moldability are improved. Injection molding is preferred.

The injection molding machine is not particularly limited, and examples thereof include a screw in-line injection molding machine and a plunger injection molding machine. The polyamine resin composition heated and melted in a cylinder of an injection molding machine is metered for each injection, and is ejected into a mold in a molten state, cooled and solidified in a predetermined shape, and then formed as a molding. The body is taken out of the mold. The resin temperature at the time of injection molding is preferably not less than the melting point (Tm) of the polyamide resin (A) and not (Tm + 50 ° C).

When the polyamide resin composition is molded, it is preferable to form an inert gas such as nitrogen, carbon dioxide or argon from the raw material supply unit of the machine to the heating unit, and to form it in an inert gas atmosphere. Thereby, it is possible to suppress discoloration caused by oxidative degradation of the organic component such as polyamine (A) and various surface treatment agents during molding, and to suppress discoloration in the step after the molding step.

Further, when the polyamide resin composition is heated and melted, it is preferred that the polyamide resin composition pellets used are sufficiently dried. When the amount of water contained is large, the resin is foamed in the cylinder of the injection molding machine, and it is difficult to obtain an optimum molded body. The water content of the pellet of the polyamide resin composition to be injection-molded is preferably less than 0.3 parts by mass, and more preferably less than 0.1 part by mass, based on 100 parts by mass of the polyamide resin composition.

Since the polyamide resin composition of the present invention is excellent in heat discoloration resistance in addition to mechanical properties, heat resistance, and flame retardancy, the molding system can be used in a wide range of automobile parts, motors/electronic parts, miscellaneous goods, and civil engineering products. the use of. Among them, in particular, since the polyamine resin composition of the present invention is particularly excellent in flame retardancy, it can be suitably used in a motor/electronic part. As the motor/electronic component, for example, a connector, an LED reflector, a switch, a sensor, a socket, a capacitor, a jack, a fuse holder, a relay, a coil bobbin, and a power failure can be cited. , electromagnetic switch, holder, plug. Further, it is also possible to suitably use a case part, a resistor, an IC, an LED case, and the like of an electric machine typified by an office automation machine such as a portable personal computer.

[Examples]

Hereinafter, the present invention will be specifically described by way of examples, but the present invention is not limited by the examples.

 1. Determination method  

The physical properties of the polyamide resin composition were measured by the following methods.

 (1) melting point  

Using a differential scanning calorimeter (DSC-7 model manufactured by Perkinelmer Co., Ltd.), the temperature was raised to 350 ° C at a temperature increase rate of 20 ° C / min, and then held at 350 ° C for 5 minutes, and the temperature was lowered to 25 ° C at a temperature drop rate of 20 ° C / min. After further maintaining at 25 ° C for 5 minutes, the temperature was measured again at a temperature increase rate of 20 ° C / minute, and the peak of the endothermic peak at this time was taken as the melting point (Tm).

 (2) Melt flow rate (MFR)  

According to JIS K7210, pellets of a polyamide resin composition were used, and the measurement was carried out at 340 ° C under a load of 1.2 kg.

The MFR system can be used as an indicator of the forming fluidity, and the higher the MFR value, the higher the fluidity.

 (3) Mechanical properties  

A test piece was produced by injection molding using a injection molding machine (Model S2000i-100B manufactured by FANUC Co., Ltd.) under the conditions of a cylinder temperature (melting point + 25 ° C) and a mold temperature (melting point - 185 ° C). (dumbbell piece).

Using the obtained test piece, the bending strength and the bending elastic modulus were measured in accordance with ISO178.

The larger the value of the bending strength and the bending elastic modulus, the more excellent the mechanical properties are.

 (4) Flame retardancy  

An injection molding machine (CND15 manufactured by NIIGATA MACHINE TECHNO Co., Ltd.) was used to produce 5 inches (127 mm) × 1/2 inch at a cylinder temperature (melting point + 25 ° C) and a mold temperature (melting point - 185 ° C). 12.7 mm) × 1/32 inch (0.79 mm) test piece.

The obtained test piece was evaluated in accordance with the standard of UL94 (Specifications prescribed by Under Writers Laboratories Inc., USA) shown in Table 1. When no benchmark is met, it is rated as "not V-2".

The shorter total flame time is indicative of excellent flame retardancy.

 (5) Yellowness (yellow index, YI), yellowness change value (△YI)  

The test piece obtained in the same manner as in the above (4) was subjected to moisture absorption treatment at 85 ° C × 85% RH for 168 hours, and then heated at 150 ° C for 1 minute in an infrared heating type reflow furnace at 100 ° C / The speed of the minute was raised to 265 ° C and held for 10 seconds.

The yellowness (YI ₁ ) of the molded body after heat treatment and the yellowness (YI ₀ ) of the molded body before heat treatment were determined by a spectrophotometer (SE6000 manufactured by Nippon Denshoku Co., Ltd.) in a C light source and a 2 degree field of view. The value of the tristimulus value XYZ is calculated in accordance with JIS K7313 according to the following formula.

YI=100(1.2769X-1.0592Z)/Y

Further, the yellowness change value (ΔYI) was calculated in accordance with the following formula.

△YI=YI ₁ -YI ₀

(6) Reflow resistance

The test piece after the reflow treatment obtained in the above (5) was observed for the presence or absence of foaming (bubble), melting, and the like, and was evaluated by the following criteria.

○: No foaming occurred and the test piece was melted.

△: Foaming occurred, but the area was 50% or less of the area of the test piece, and the test piece was not melted.

×: Foaming of 50% or more of the area of the test piece or melting of the test piece was caused.

 2. Raw materials  

The materials used in the examples and comparative examples are disclosed below.

 (1) Polyamide (A)    ‧ Polyamide (A-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 were added thereto. With a blending type reaction apparatus, the mixture was stirred at a number of revolutions of 30 rpm while being nitrogen-sealed while being heated to 170 °C. Thereafter, the temperature was maintained at 170 ° C, and the number of revolutions was maintained at 30 rpm, and 1,10-decanediamine (DDA) 4.98 kg as a diamine component which was heated to 100 ° C was used using a liquid injection device. The reaction product was obtained by continuously adding (continuous liquid injection) for 2.5 hours. Further, the molar ratio of the raw material monomers was TPA:DDA:STA=48.5:49.6:1.9 (the equivalent ratio of the functional groups of the raw material monomers was TPA:DDA:STA=49.0:50.0:1.0).

Next, the obtained reaction product was heated in a nitrogen gas stream at 250 ° C, a number of revolutions of 30 rpm for 8 hours, and polymerized to produce a powder of polyamine.

Thereafter, the obtained polyamidamide powder was formed into a strand shape using a biaxial kneader, and the strands were cooled and solidified by a water tank, and cut using a granulator to obtain polyamine (A-1). ) pellets.

 ‧ Polyamide (A-2) to (A-4)  

Polyamines (A-2) to (A-4) were obtained in the same manner as in the polyamine (A-1) except that the resin composition was changed as shown in Table 2.

The resin composition and characteristic values of the above polyamines (A-1) to (A-4) are shown in Table 2.

TPA: terephthalic acid, AA: adipic acid

DDA: 1,10-decanediamine, NDA: 1,9-decanediamine, HDA: 1,6-hexanediamine, BDA: 1,4-butanediamine

STA: Stearic acid

 (2) Phosphorus-based flame retardant (B)  

‧B-1: phosphinate (Exolit OP1230 by CLARIANT)

‧B-2: hexaphenoxycyclotriphosphazene (Rabitle FP-100, Fushimi Pharmaceutical Co., Ltd.)

 (3) fibrous reinforcing material (C)  

‧C-1: Glass fiber (03JAFT692 manufactured by ASAHI FIBER GLASS), average fiber diameter 10 μm, average fiber length 3 mm

 (4) Flame retardant additives (D)  

‧D-1: Melamine polyphosphate (Melapur 200/70, manufactured by BASF)

‧D-2: Zinc borate 4ZnO. B ₂ O ₃ . H ₂ O (Firebrake 415 manufactured by Borax)

 (5) Phosphorus-based antioxidants (E)  

‧E-1: bis(2,4-di-t-butylphenyl) 4,4'-extended biphenyl-di-phosphinate (HOSTANOX P-EPQ, manufactured by Clariant)

 (6) Talc (F)  

‧F-1: talc (MSZ-C, Japan talc company, average particle size 11μm, surface treated product)

 Example 1  

100 parts by mass of polyamine (A-1), 3 parts by mass of melamine polyphosphate (D-1), 3 parts by mass of zinc borate (D-2), and 0.4 parts by mass of phosphorus-based antioxidant (E-1) were dry-type. In the same direction, the same type of twin-screw extruder (Toshiba Machine Co., Ltd. TEM26SS type) was used for the measurement and the measurement was carried out using a weight-reduction type continuous quantitative supply device (CE-W-1 type manufactured by KUBOTA Co., Ltd.) and supplied to a coaxial screw with a screw diameter of 26 mm and L/C50. The main supply port (base) is melt-kneaded. Then, 17.0 parts by mass of the phosphorus-based flame retardant (B-1) and 30 parts by mass of the glass fiber (C-1) are supplied from the side feeder 1, and further kneaded, and then, from the side feeder 1 The side feeder 2 on the downstream side supplied 17.0 parts by mass of the phosphorus-based flame retardant (B-1) and 30 parts by mass of the glass fiber (C-1). Further, any of the side feeders is disposed on the downstream side of the first kneading portion which melts the polyamide (A-1) in the co-axial extruder of the same direction. In addition, nitrogen gas is conducted from the main supply port of the dosing device, the main supply port of the extruder, and the side feeder, and is maintained so that the oxygen concentration is 1% or less. After the polyamide resin composition was drawn into a strand shape from the die, it was cooled and solidified by a water tank, and cut with a granulator to obtain pellets of a polyamide resin composition. The barrel temperature setting of the extruder was set to (melting point - 5 ° C) to (melting point + 15 ° C), the number of revolutions of the screw was 250 rpm, and the amount of discharge was 25 kg / h.

Examples 2 to 11 and Comparative Examples 1 to 6

In addition to changing the composition of the resin composition, the number of side feeders, and the addition amount of the phosphorus-based flame retardant (B) and the fibrous reinforcing material (C) per one portion as shown in Tables 3 and 4, The same operation as in Example 1 was carried out to obtain a pellet of a polyamide resin composition.

Various evaluation tests were carried out using the obtained polyamide resin composition pellets. The results are shown in Tables 3 and 4.

The resin composition of the examples is low in yellowness, excellent in heat resistance, mechanical properties, and flame retardancy, and also excellent in heat discoloration resistance, and has a low change in yellowness after reflow treatment.

Compared with Example 3 and Comparative Example 1, since the polyamide composition (A) of the resin compositions of Examples 1 and 2 has a high melting point, it is excellent in reflow resistance and does not cause foaming, and after the reflow step The shape of the formed body is also maintained.

In Example 4, in which the resin composition of Example 3 contained talc (F), foaming was suppressed, and the shape of the molded body was maintained after the reflow step.

The phosphorus-based flame retardant (B) of the resin composition of Example 1 is a phosphinate, and has superior flame retardancy as compared with Example 8 (phosphazene compound).

Since the resin composition of Comparative Example 2 does not contain the phosphorus-based flame retardant (B), the flame retardancy is inferior.

The resin composition of Comparative Examples 3 to 6 is produced by adding the amount of the phosphorus-based flame retardant (B) per one side feeder to more than 20 parts by mass based on 100 parts by mass of the polyamide (A). The polyamine is deteriorated and the yellowness is high, and the heat discoloration property is inferior, and the change in the yellowness after the reflow treatment is large.

Claims (11)

A polyamidamide resin composition comprising 100 parts by mass of polyamine (A) having a melting point of 270 to 350 ° C, 10 to 80 parts by mass of a phosphorus-based flame retardant (B), and a yellowness (YI ₀ ) of 3.0 the following.  The polyamide resin composition according to claim 1, wherein the yellowness change value (ΔYI) after the reflow treatment at 265 ° C is 12.0 or less.    The polyamine resin composition according to claim 1 or 2, wherein the phosphorus-based flame retardant (B) is a phosphinate and/or a diphosphinate.   The polyamine resin composition according to claim 3, wherein the phosphinate is a compound represented by the following formula (I), and the diphosphinate is represented by the following formula (II). Compound, Wherein R ¹ , R ² , R ⁴ and R ⁵ are each independently and represent a C 1 to 16 alkyl or phenyl group of a straight or branched chain, and R ³ represents a straight or branched chain carbon. a number 1 to 10 alkylene group, a carbon number 6 to 10 aryl group, an alkyl alkyl group, or an alkyl aryl group, and M represents a calcium ion, an aluminum ion, a magnesium ion or a zinc ion, and m is 1 or 3, n, a, and b are integers satisfying the relationship of 2 × b = n × a.  The polyamide resin composition according to any one of claims 1 to 4, further comprising 5 to 140 parts by mass of the fibrous reinforcing material (C).    The polyamide resin composition according to any one of claims 1 to 5, which further contains 0.1 to 20 parts by mass of talc (F).    A method for producing a polyamide resin composition, which is a method for producing a polyamide resin composition according to any one of claims 1 to 6, which is a polyamine (A) and a phosphorus system. In the melt-kneading of the flame retardant (B), one or more side feeders are provided in the melt kneading machine, and the phosphorus system resistance per one side feeder is 100 parts by mass relative to the polyamide (A). The amount of the fuel (B) to be added is 20 parts by mass or less, and the phosphorus-based flame retardant (B) is added from the side feeder.    A method for producing a polyimide resin composition, which is a method for producing a polyamide resin composition according to claim 5, wherein a fibrous reinforcing material is used in melt-kneading of a resin composition ( C) is added in multiples.    The method for producing a polyamide resin composition according to claim 7 or 8, wherein the polyamine (A) is polymerized before melt-kneading, and the polymerization is carried out under an inert gas atmosphere.    The method for producing a polyamide resin composition according to any one of claims 7 to 9, wherein the polyamine (A) and the phosphorus-based flame retardant (B) are carried out under an inert gas atmosphere. Melt and knead.    A molded article obtained by molding the polyamide resin composition according to any one of claims 1 to 6.