JP6955763B2 - Polyamide resin composition and molded article obtained by molding the polyamide resin composition - Google Patents

Description

The present invention relates to a flame-retardant polyamide resin composition.

Polyamide has excellent heat resistance and mechanical properties, and is used as many electric / electronic parts and parts around automobile engines. Among these parts, polyamides used in electrical and electronic parts are required to have even 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 heightened environmental awareness, halogen-based flame retardants have been avoided, and non-halogen flame retardants are generally used.
For example, Patent Document 1 discloses that a mixture of a reaction product of melamine and phosphoric acid, a metal phosphinic acid salt, and a metal compound is used as a non-halogen flame retardant, and is a 1/16 inch molded product. It is disclosed that the flame retardant standard UL94V-0 standard is satisfied. However, the polyamide resin composition containing a metal phosphinic acid salt is highly corrosive to metals, and during melt processing, the screws and dies of the extruder and the metal parts such as the screws and dies of the molding machine are severely worn. , There was a problem of lack of mass productivity. Further, this composition has a problem that a large amount of gas is generated during the molding process and dirt adheres to the mold.

In addition, surface mounting is the mainstream for mounting electrical and electronic components, and in the reflow process, the polyamides that make up the components are exposed to a high temperature of about 260 ° C. at the maximum temperature. Therefore, there are many cases where it is necessary to use a heat-resistant polyamide having a reflow resistance and a melting point of 270 ° C. or higher as the polyamide. Since the heat-resistant polyamide has a high processing temperature due to its high melting point, the heat-resistant polyamide resin composition containing a metal salt of phosphinic acid has a problem that the metal corrosiveness is further increased at the time of melt processing.

Various techniques for blending an auxiliary agent have been disclosed as a method for suppressing metal corrosiveness and gas generation in response to these problems. Patent Document 2 uses calcium oxide, and Patent Documents 3 to 4 provide. A technique for blending an inorganic metal compound or a fatty acid metal salt as an auxiliary agent is disclosed, Patent Document 5 discloses a technique for blending an inorganic aluminum compound with a polyamide having a specific structure, and Patent Document 6 discloses under specific conditions. Extruding techniques are disclosed. However, these technologies are technologies that sacrifice flame retardancy and mechanical properties, and cannot be said to be sufficient as the wall thickness, miniaturization, and high performance are required more and more.

JP-A-2007-0232206 Special Table 2012-523469 Japanese Patent Application Laid-Open No. 2011-513540 International Publication No. 2008/126381 International Publication No. 2014/148519 International Publication No. 2009/107514

The present invention solves the above-mentioned problems in a resin composition composed of a semi-aromatic polyamide containing a metal salt of phosphinic acid and having a melting point of 300 to 350 ° C., which requires melt processing at a high temperature in which a metal corrosive action is promoted. An object of the present invention is to provide a polyamide resin composition capable of suppressing metal corrosiveness while having high flame retardancy and mechanical properties, which has been difficult to achieve by the prior art.

As a result of intensive studies to solve the above problems, the present inventors have made a polyamide resin composition containing a metal salt of phosphinic acid excellent in flame retardancy by containing a specific amount of a plurality of specific compounds. We have found that metal corrosiveness during melt processing is suppressed while having mechanical properties, and have reached the present invention. That is, the gist of the present invention is as follows.

（式中、Ｒ^１、Ｒ^２、Ｒ^４およびＲ^５は、それぞれ独立して、直鎖または分岐鎖の炭素数１〜１６のアルキル基またはフェニル基を表す。Ｒ^３は、直鎖もしくは分岐鎖の炭素数１〜１０のアルキレン基、炭素数６〜１０のアリーレン基、アリールアルキレン基、または、アルキルアリーレン基を表す。Ｍは、カルシウムイオン、アルミニウムイオン、マグネシウムイオンまたは亜鉛イオンを表す。ｍは、２または３である。ｎ、ａ、ｂは、２×ｂ＝ｎ×ａの関係式を満たす整数である。）
（３）炭酸金属塩（Ｃ）を構成する金属が、カルシウム、マグネシウム、ナトリウム、リチウムからなる群から選択される少なくとも１種であることを特徴とする（１）または（２）に記載のポリアミド樹脂組成物。
（４）脂肪酸バリウム塩（Ｄ）を構成する脂肪酸が、ラウリン酸、ステアリン酸、１２−ヒドロキシステアリン酸、ベヘン酸、モンタン酸からなる群から選択される少なくとも１種であることを特徴とする（１）〜（３）のいずれかに記載のポリアミド樹脂組成物。
（５）ヒンダードフェノール構造を有するヒドラジン系化合物（Ｅ）が、下記式（III）で表される化合物であることを特徴とする（１）〜（４）のいずれかに記載のポリアミド樹脂組成物。

（６）さらに融点が２００〜３００℃の脂肪族ポリアミド（Ｆ）を含有することを特徴とする（１）〜（５）のいずれかに記載のポリアミド樹脂組成物。
（７）さらに強化材（Ｇ）を５〜６０質量％含有することを特徴とする（１）〜（６）のいずれかに記載のポリアミド樹脂組成物。
（８）強化材（Ｇ）が、平均粒径が１０〜３０μｍであるタルクを含有することを特徴とする（７）記載のポリアミド樹脂組成物。
（９）（１）〜（８）のいずれかに記載のポリアミド樹脂組成物を成形してなることを特徴とする成形体。 (1) 20 to 80% by mass of a semi-aromatic polyamide (A) having a melting point of 300 to 350 ° C., 5 to 30% by mass of a metal phosphinic acid salt (B), and 0.1 to 8% by mass of a metal carbonate (C). A polyamide resin composition containing 0.01 to 3% by mass of a fatty acid barium salt (D) and 0.01 to 5% by mass of a hydrazine-based compound (E) having a hindered phenol structure. ..
(2) The polyamide resin composition according to (1), wherein the phosphinic acid metal salt (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 independently represent an alkyl group or a phenyl group having 1 to 16 carbon atoms in a linear or branched chain, respectively. R ³ is a linear or branched chain or branched chain. It 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. M represents a calcium ion, an aluminum ion, a magnesium ion or a zinc ion. Is 2 or 3. n, a, b are integers satisfying the relational expression of 2 × b = n × a.)
(3) The polyamide according to (1) or (2), wherein the metal constituting the metal carbonate (C) is at least one selected from the group consisting of calcium, magnesium, sodium and lithium. Resin composition.
(4) The fatty acid constituting the fatty acid barium salt (D) is at least one selected from the group consisting of lauric acid, stearic acid, 12-hydroxystearic acid, behenic acid, and montanic acid (1). The polyamide resin composition according to any one of 1) to (3).
(5) The polyamide resin composition according to any one of (1) to (4), wherein the hydrazine-based compound (E) having a hindered phenol structure is a compound represented by the following formula (III). thing.

(6) The polyamide resin composition according to any one of (1) to (5), further containing an aliphatic polyamide (F) having a melting point of 200 to 300 ° C.
(7) The polyamide resin composition according to any one of (1) to (6), further containing 5 to 60% by mass of the reinforcing material (G).
(8) The polyamide resin composition according to (7), wherein the reinforcing material (G) contains talc having an average particle size of 10 to 30 μm.
(9) A molded product obtained by molding the polyamide resin composition according to any one of (1) to (8).

According to the present invention, in a resin composition containing a high melting point polyamide and a metal salt of phosphinic acid, the two properties of high flame retardancy and low metal corrosiveness, which have been difficult to achieve in the past, are compatible at a high level. It is possible to provide a flame-retardant polyamide resin composition capable of this, and at the same time, it is possible to provide a molded product having excellent mechanical properties.

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

Hereinafter, the present invention will be described in detail.
The polyamide resin composition of the present invention comprises a semi-aromatic polyamide (A), a metal phosphinic acid salt (B), a metal carbonate (C), a fatty acid barium salt (D), and a hydrazine compound having a hindered phenol structure ( E) is contained.

In the polyamide resin composition of the present invention, the content of the semi-aromatic polyamide (A) needs to be 20 to 80% by mass and 30 to 75% by mass with respect to the entire resin composition. It is preferably 40 to 55% by mass, more preferably 40 to 55% by mass. When the content of the semi-aromatic polyamide (A) is less than 20% by mass, the resin composition becomes difficult to melt-knead or melt-mold, or the mechanical properties are deteriorated, while the semi-aromatic polyamide (A) If the content of A) exceeds 80% by mass, it may be difficult for the resin composition to exhibit high flame retardancy.

In the present invention, the semi-aromatic polyamide (A) contains an aromatic dicarboxylic acid component and an aliphatic diamine component as constituent components. The semi-aromatic polyamide (A) may contain a copolymerization component, but it is copolymerized in terms of heat resistance, mechanical strength, chemical resistance, rapid crystallization, and a molded product can be obtained with a low-temperature mold. That is, it is preferably composed of a single aromatic dicarboxylic acid component and a single aliphatic diamine component.

In the present invention, examples of the aromatic dicarboxylic acid component constituting the semi-aromatic polyamide (A) include terephthalic acid, phthalic acid, isophthalic acid, and naphthalenedicarboxylic acid. Of these, terephthalic acid is preferable because it can improve heat resistance.

Examples of the acid component to be copolymerized in addition to the aromatic dicarboxylic acid component include oxalic acid, malonic acid, succinic acid, glutaric acid, adipic acid, pimelli acid, suberic acid, azelaic acid, sebacic acid, undecanedioic acid, dodecanedioic acid and the like. Examples thereof include an aliphatic dicarboxylic acid of the above and a dicarboxylic acid such as an alicyclic dicarboxylic acid such as cyclohexanedicarboxylic acid. The amount of copolymerization of aromatic dicarboxylic acids, aliphatic dicarboxylic acids, and alicyclic dicarboxylic acids other than terephthalic acid is the total number of moles of the raw material monomer so as not to lower the melting point and heat resistance of the semi-aromatic polyamide (A). On the other hand, it is preferably 5 mol% or less, and more preferably not substantially contained.

In the present invention, examples of the aliphatic diamine component constituting the semi-aromatic polyamide (A) include 1,2-ethanediamine, 1,3-propanediamine, 1,4-butanediamine, and 1,5-pentanediamine. , 1,6-hexanediamine, 1,7-heptanediamine, 1,8-octanediamine, 1,9-nonandiamine, 1,10-decanediamine, 1,11-undecanediamine, 1,12-dodecanediamine, 2 Examples thereof include -methyl-1,5-pentanediamine and 2-methyl-1,8-octanediamine. It is preferable to use one type of aliphatic diamine component alone rather than using the above-mentioned plurality of types in combination, and the molding has a good balance of heat resistance, mechanical properties, and water absorption, and also has excellent chemical resistance. It is preferable to use 1,10-decanediamine alone because a body can be obtained.

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

In the present invention, examples of copolymerization components other than those constituting the semi-aromatic polyamide (A) include lactams such as caprolactam and laurolactam, and ω-aminocarboxylic acids such as aminocaproic acid and 11-aminoundecanoic acid. The amount of these copolymerizations is preferably 5 mol% or less with respect to the total number of moles of the raw material monomers so as not to deteriorate the heat resistance, mechanical properties, and chemical resistance of the semi-aromatic polyamide (A). It is more preferable that it is substantially not contained.

In the present invention, the semi-aromatic polyamide (A) 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%, preferably 0.3 to 3.0 mol%, based on all the monomer components constituting the semi-aromatic polyamide (A). It is more preferably 0.3 to 2.5 mol%, and particularly preferably 0.8 to 2.5 mol%. By containing a monocarboxylic acid component within the above range, the molecular weight distribution during polymerization can be reduced, the releasability during molding can be improved, and the amount of gas generated during molding can be suppressed. Can be done. On the other hand, if the content of the monocarboxylic acid component exceeds the above range, the mechanical properties and flame retardancy may deteriorate. In the present invention, the content of the monocarboxylic acid refers to the ratio of the residue of the monocarboxylic acid in the semi-aromatic polyamide (A), that is, the monocarboxylic acid desorbed from the terminal hydroxyl group.

The semi-aromatic polyamide (A) 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 can be improved, the amount of gas generated at the temperature during molding can be suppressed, 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 gas generated by the polyamide-derived component is reduced, mold stains are reduced, and separation is performed. An aliphatic monocarboxylic acid is preferable because it can improve the moldability.
Examples of aliphatic monocarboxylic acids 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 preferable 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 aromatic monocarboxylic acids 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. Further, a monocarboxylic acid having a molecular weight of 140 or more and a monocarboxylic acid having a molecular weight of less than 140 may be used in combination. In the present invention, the molecular weight of the monocarboxylic acid refers to the molecular weight of the raw material monocarboxylic acid.

In the present invention, the semi-aromatic polyamide (A) needs to have a melting point of 300 to 350 ° C., preferably 310 to 350 ° C., and more preferably 315 to 340 ° C. When the melting point of the semi-aromatic polyamide (A) is less than 300 ° C., the obtained polyamide resin composition has insufficient heat resistance. On the other hand, when the melting point of the semi-aromatic polyamide (A) exceeds 350 ° C., the decomposition temperature of the polyamide bond is about 350 ° C., so that carbonization and decomposition proceed during the melt processing. In the present invention, the melting point is set to be the top of the endothermic peak when the temperature is raised at a heating rate of 20 ° C./min by a differential scanning calorimeter (DSC).

In the present invention, the semi-aromatic polyamide (A) preferably has a melt flow rate (MFR) of 1 to 200 g / 10 minutes, more preferably 10 to 150 g / 10 minutes, and 20 to 120 g / 10 minutes. Minutes are even more preferred. The MFR can be used as an index of molding fluidity, and the higher the MFR value, the higher the fluidity. If the MFR of the semi-aromatic polyamide (A) exceeds 200 g / 10 minutes, the mechanical properties of the obtained resin composition may deteriorate, and the MFR of the semi-aromatic polyamide (A) is less than 1 g / 10 minutes. If there is, the fluidity may be extremely low and melt processing may not be possible.

The semi-aromatic polyamide (A) can be produced by using a conventionally known method of heat polymerization method or solution polymerization method. Among them, the heat polymerization method is preferably used because it is industrially advantageous.

The polyamide resin composition of the present invention contains a metal phosphinic acid salt (B).
In the present invention, the content of the metal phosphinic acid salt (B) needs to be 5 to 30% by mass, preferably 8 to 25% by mass, and 8 to 20% by mass with respect to the entire resin composition. It is more preferably mass%. If the content of the phosphinic acid metal salt (B) is less than 5% by mass, it becomes difficult to impart the required flame retardancy to the resin composition. On the other hand, if the content of the metal phosphinic acid salt (B) exceeds 30% by mass, the resin composition is excellent in flame retardancy, but the metal corrosiveness becomes large and melt kneading may become difficult. In addition, the obtained molded product may have insufficient mechanical properties.

Examples of the phosphinic acid metal salt (B) in the present invention include a phosphinic acid metal salt represented by the following general formula (I) and a diphosphanic acid metal salt represented by the general formula (II).

In the formula, R ¹ , R ² , R ⁴ and R ⁵ each need to be an alkyl group or a phenyl group having 1 to 16 carbon atoms in a straight chain or a branched chain, respectively, and have 1 to 8 carbon atoms. It is preferably an alkyl group or a phenyl group, and is 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 preferably, it is more preferably an ethyl group. R ¹ and R ² and R ⁴ and R ⁵ may form rings with each other.
R ³ needs 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 alkylene group having 1 to 10 carbon atoms in the linear or branched chain include a methylene group, an ethylene group, an n-propylene group, an isopropylene group, an isopropylidene group, an n-butylene group, a tert-butylene group and an n-. Examples thereof include a pentylene group, an n-octylene group and an n-dodecylene group. 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 ion include calcium ion, aluminum ion, magnesium ion and zinc ion, and aluminum ion and zinc ion are preferable, and aluminum ion is 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 diphosphane ions, and n, a, and b are integers satisfying the relational expression of “2 × b = n × a”.

The phosphinic acid metal salt and the diphosphinic acid metal salt are produced in an aqueous solution using the corresponding phosphinic acid and diphosphinic acid, respectively, and a metal carbonate, a metal hydroxide or a metal oxide, and usually exist as a monomer. Depending on the reaction conditions, it may exist in the form of a polymer phosphinate having a degree of condensation of 1-3.

Specific examples of the phosphinate represented by the above general formula (I) include, for example, calcium dimethylphosphinate, magnesium dimethylphosphinate, aluminum dimethylphosphinate, zinc dimethylphosphite, calcium ethylmethylphosphinate, and ethylmethylphosphine. Magnesium Acid, Aluminum Ethylmethylphosphinate, Zinc Ethylmethylphosphinate, Calcium diethylphosphinate, Magnesium diethylphosphinate, Aluminum diethylphosphinate, Zinc diethylphosphinate, Calcium methyl-n-propylphosphinate, Methyl-n-propylphosphine Magnesium Acid, Aluminum Methyl-n-propylphosphinate, Zinc Methyl-n-propylphosphinate, Calcium Methylphenylphosphinate, Magnesium Methylphenylphosphinate, Aluminum Methylphenylphosphite, Zinc Methylphenylphosphinate, Calcium diphenylphosphinate, Examples thereof include magnesium diphenylphosphinate, aluminum diphenylphosphinate, and zinc diphenylphosphinate. Among them, aluminum diethylphosphinate and zinc diethylphosphinate are preferable, and aluminum diethylphosphinate is more preferable, because they are excellent in flame retardancy and an excellent balance of electrical characteristics.

Examples of the diphosphinic acid used for producing the diphosphinate include methanedi (methylphosphinic acid) and benzene-1,4-di (methylphosphinic acid).

Specific examples of the diphosphinate represented by the above general formula (II) include calcium methanedi (methylphosphinic acid), magnesium methanedi (methylphosphinic acid), aluminum methanedi (methylphosphinic acid), 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 can be mentioned. Of these, methanedi (methylphosphinic acid) aluminum and methanedi (methylphosphinic acid) zinc are preferable because they have an excellent balance of flame retardancy and electrical characteristics.

Specific products of the phosphinic acid metal salt (B) include, for example, "Exolit OP1230", "Exolit OP1240", "Exolit OP1312", "Exolit OP1314" and "Exolit OP1400" manufactured by Clariant AG.

The polyamide resin composition of the present invention needs to contain a metal carbonate (C) in order to obtain an effect of suppressing metal corrosiveness, and the content of the metal carbonate (C) is the resin composition. It needs to be 0.1 to 8% by mass, preferably 0.2 to 5% by mass, and more preferably 0.5 to 3% by mass with respect to the whole. If the content of the metal carbonate (C) in the polyamide resin composition is less than 0.1% by mass, a sufficient effect of suppressing metal corrosion cannot be obtained. On the other hand, if the content of the metal carbonate (C) exceeds 8% by mass, the flame retardancy of the polyamide resin composition is adversely affected, and the polyamide resin composition cannot obtain sufficient flame retardancy.

Examples of the metal constituting the metal carbonate (C) include calcium, magnesium, sodium, lithium, potassium and barium, and calcium, magnesium, sodium and lithium are preferable from the viewpoint of thermal stability and safety. , Calcium, magnesium are more preferred, and calcium is particularly preferred.

The polyamide resin composition of the present invention needs to contain a fatty acid barium salt (D) in order to obtain an effect of suppressing metal corrosiveness, and the content of the fatty acid barium salt (D) is the resin composition. It needs to be 0.01 to 3% by mass, preferably 0.05 to 2% by mass, and more preferably 0.1 to 1.5% by mass with respect to the whole. When the content of the fatty acid barium salt (D) in the polyamide resin composition is less than 0.01% by mass, a sufficient effect of suppressing metal corrosion cannot be obtained. On the other hand, if the content of the fatty acid barium salt (D) exceeds 3% by mass, the mechanical properties of the polyamide resin composition are greatly adversely affected, and the polyamide resin composition cannot obtain sufficient mechanical strength.

The fatty acids constituting the fatty acid barium salt (D) include capric acid (C10), lauric acid (C12), myristic acid (C14), pentadecanoic acid (C15), palmitic acid (C16), margaric acid (C17), and stearer. Acid (C18), 12-hydroxystearic acid, arachidic acid (C20), behenic acid (C22), lignoseric acid (C24), cellotic acid (C26), montanic acid (C28), melicic acid (C30), erucic acid, Examples include ricinolic acid. From the viewpoint of availability and thermal stability, lauric acid, stearic acid, 12-hydroxystearic acid, behenic acid, and montanic acid are preferable, and stearic acid is particularly preferable.

The hydrazine-based compound (E) having a hindered phenol structure used in the present invention has both a hindered phenol structure having an effect of capturing peroxy radicals and a hydrazine structure chelating metal ions. Specifically, a compound represented by the following formula (III) can be mentioned.

When the polyamide resin composition contains the phosphinic acid metal salt (B), the flame retardancy is improved, but as described above, the metal corrosiveness is increased. However, the phosphinic acid metal salt (B) -containing polyamide resin composition can suppress metal corrosiveness by containing the above metal carbonate (C) or fatty acid barium salt (D), and these are simultaneously contained. Then, the metal corrosiveness can be remarkably suppressed. On the other hand, when the phosphinic acid metal salt (B) -containing polyamide resin composition contains the metal carbonate (C) and the fatty acid barium salt (D) at the same time, the flame retardancy is significantly reduced.
However, by further containing the hydrazine-based compound (E) having a hindered phenol structure, the resin composition can dramatically improve the flame retardancy, and as a result, the resin composition has high flame retardancy and also has high flame retardancy. A resin composition in which metal corrosiveness is suppressed can be obtained. Further, the resin composition containing the hydrazine-based compound (E) having a hindered phenol structure can reduce the content of the phosphinic acid metal salt (B) and further suppress the metal corrosiveness.

The content of the hydrazine-based compound (E) having a hindered phenol structure needs to be 0.01 to 5% by mass and 0.05 to 3% by mass with respect to the entire resin composition. It is preferably 0.1 to 2% by mass, more preferably 0.1 to 2% by mass. When the content of the hydrazine-based compound (E) having a hindered phenol structure is less than 0.01% by mass, the effect of improving the flame retardant efficiency cannot be obtained, while when the content exceeds 5% by mass, the effect of improving the flame retardant efficiency cannot be obtained. Not only is the flame retardant efficiency saturated and no further improvement effect can be expected, but the resulting molded product may have insufficient mechanical strength.

Specific products of the hydrazine-based compound (E) having a hindered phenol structure include, for example, "CDA-10" manufactured by Adeka Corporation and "IRGANOX MD 1024" manufactured by BAF.

The polyamide resin composition of the present invention contains a specific amount of each of a phosphinic acid metal salt (B), a metal carbonate (C), a fatty acid barium salt (D), and a hydrazine compound (E) having a hindered phenol structure. Therefore, the high flame retardancy, high mechanical properties, and low metal corrosiveness of the high melting point polyamide resin composition can all be satisfied. That is, it is possible to reduce the corrosion and wear of metal parts such as the screw and die of the extruder during the melt extrusion process and the screw and mold of the molding machine during the melt extrusion process. Since the metal corrosiveness of the polyamide resin composition containing the phosphinic acid metal salt (B) is particularly remarkable in the melt processing at a high temperature, the composition of the resin composition of the present invention is a resin containing a high melting point polyamide. A particularly excellent effect can be exhibited in the composition.

The polyamide resin composition of the present invention may contain an aliphatic polyamide (F) having a melting point of 200 to 300 ° C., in addition to the semi-aromatic polyamide (A) having a melting point of 300 ° C. to 350 ° C. By containing the aliphatic polyamide (F) having a melting point of 200 to 300 ° C., the resin composition has high fluidity derived from the aliphatic polyamide (F) while having heat resistance derived from the semi-aromatic polyamide. It is possible to design a well-balanced resin composition that also has. Further, since the resin composition has high fluidity, the melting processing temperature can be lowered, and the shear heat generation of the resin can be suppressed, so that the metal corrosiveness can be further suppressed.

Examples of the aliphatic polyamide (F) having a melting point of 200 to 300 ° C. include polyamide 6, polyamide 66, polyamide 46, polyamide 10, polyamide 610, polyamide 612, polyamide 1010, polyamide 11, polyamide 12, and polyamide 66/6 copolymer. And so on. Among them, polyamide 6, polyamide 66, and polyamide 46 are preferable, and polyamide 6 and polyamide 66 are more preferable, from the viewpoint of fluidity.

The mass ratio (A / F) of the semi-aromatic polyamide (A) to the aliphatic polyamide (F) is preferably 95/5 to 30 to 70, more preferably 70/30 to 40/60. ..

The polyamide resin composition of the present invention preferably further contains a reinforcing material (G).
When the reinforcing material (G) is contained, the content is preferably 5 to 60% by mass, more preferably 10 to 50% by mass, and 20 to 50% by mass with respect to the entire resin composition. It is more preferable to have. When the content of the reinforcing material (G) is less than 5% by mass, the resin composition may have a small effect of improving the mechanical properties. On the other hand, when the content exceeds 60% by mass, not only the effect of improving the mechanical properties of the resin composition is saturated and no further improvement effect can be expected, but also the workability at the time of melting processing is lowered, and the resin composition is reduced. It can be difficult to obtain pellets of material.

Since the polyamide resin composition of the present invention has a high effect of improving mechanical properties, it is preferable to contain a fibrous reinforcing material as the reinforcing material (G).
The fibrous reinforcing material is not particularly limited, but for example, glass fiber, carbon fiber, boron fiber, asbestos fiber, polyvinyl alcohol fiber, polyester fiber, acrylic fiber, total aromatic polyamide fiber, polybenzoxazole fiber, polytetrafluoro. Examples thereof include ethylene fiber, kenaf fiber, bamboo fiber, hemp fiber, bagas fiber, high-strength polyethylene fiber, alumina fiber, silicon carbide fiber, potassium titanate fiber, brass fiber, stainless fiber, steel fiber, ceramics fiber, and genbuiwa fiber. Among them, 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 at the time of melt-kneading with polyamide (A), and are easily available. The fibrous reinforcing material may be used alone or in combination.

The glass fiber and 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 vinylsilane-based, acrylicsilane-based, epoxysilane-based, and aminosilane-based agents. Among them, the semi-aromatic polyamide (A) has a high adhesion effect with glass fiber or carbon fiber. Aminosilane-based coupling agents are preferred.

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, more preferably 0.5 to 6 mm. Since 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, more preferably 5 to 13 μm. Since 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-sectional shapes, and a circular shape is preferable.

The polyamide resin composition of the present invention preferably further contains a plate-like reinforcing material such as talc, glass flakes, mica, graphite, and metal foil in addition to the above-mentioned fibrous reinforcing material, and has an average particle size of 10 to 10. It is more preferable to contain 30 μm talc. When the polyamide resin composition contains the aliphatic polyamide (F), the fluidity becomes high, but the reflow resistance is lowered, and blister may be generated. However, by containing talc having the above average particle size, it is possible to suppress the generation of blister during reflow.
The talc may be surface-treated with an organic compound such as a silane coupling agent. By surface treatment, the adhesion to the semi-aromatic polyamide (A) and the aliphatic polyamide (F) is improved, which is effective in improving the strength and suppressing blister.
In the present invention, the average particle size of talc refers to the median diameter (D50) obtained by laser diffraction.
When talc is contained, the content is preferably 3 to 15% by mass and more preferably 5 to 10% by mass with respect to the entire resin composition. When the talc content is less than 3% by mass, the blister suppressing effect at the time of reflow is small.

The polyamide resin composition of the present invention may contain a spherical reinforcing material as the reinforcing material (G), and the spherical reinforcing material includes carbon black, silicon carbide, silica, quartz powder, hydrotalcite, molten silica, and the like. Glasses (glass beads, glass powder, milled glass fiber), silicates (calcium silicate, aluminum silicate, kaolin, clay, diatomaceous soil, etc.), metal oxides (iron oxide, titanium oxide, zinc oxide, alumina) Etc.), sulfates (calcium silicate, barium sulfate, etc.) and the like.

The polyamide resin composition of the present invention may further contain a flame retardant aid. Examples of the flame retardant aid include a nitrogen-based flame retardant, a nitrogen-phosphorus flame retardant, and an inorganic flame retardant.

Examples of the nitrogen-based flame retardant include a melamine-based compound, cyanuric acid, or a salt of isocyanuric acid and a melamine compound. Specific examples of melamine compounds include melamine, melamine derivatives, compounds having a structure similar to melamine, and condensates of melamine. Specifically, melamine, ammelide, ammeline, formoguanamine, guanyl melamine, and 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 an adduct (melamine adduct) formed from melamine or a condensation product thereof and a phosphorus compound, and a phosphazene 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, polyphosphoric acid and the like. Specific examples of the melamine adduct include melamine phosphate, melamine pyrophosphate, dimelamine pyrophosphate, melamine polyphosphate, melem polyphosphate, and melamine polyphosphate, and among them, 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, "Rabbitl FP-100" and "Rabbitl FP-110" manufactured by Fushimi Pharmaceutical Co., Ltd., "SPS-100" and "SPB-100" manufactured by Otsuka Chemical Co., Ltd. ..

Examples of the inorganic flame retardant include metal hydroxides such as magnesium hydroxide and calcium hydroxide, zinc salts such as zinc borate and zinc phosphate, and calcium aluminates.

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-based antioxidant include inorganic phosphates such as monosodium phosphate, disodium phosphate, trisodium phosphate, sodium phosphite, calcium phosphite, magnesium phosphite, and manganese phosphite, and birds. Phosphorphosphite, trioctadecylphosphite, tridecylphosphite, trinonylphenylphosphite, diphenylisodecylphosphite, bis (2,6-di-tert-butyl-4-methylphenyl) pentaerythritol diphosphite (" Adecastab PEP-36 "), Bis (2,4-di-tert-butylphenyl) pentaerythritol diphosphite (" Adecastab PEP-24G "), Tris (2,4-di-tert-butylphenyl) phosphite, Distearyl pentaerythritol diphosphite ("Adecastab PEP-8"), bis (nonylphenyl) pentaerythritol diphosphite ("Adecastab PEP-4C"), 1,1'-biphenyl-4,4'-diylbis [sub Bisphosphonate (2,4-di-tert-butylphenyl)], Tetrax (2,4-di-tert-butylphenyl) 4,4'-biphenylene-di-phosphonite ("Hostanox P-EPQ"), Examples thereof include organic phosphorus compounds such as tetra (tridecyl-4,4'-isopropyridene diphenyldiphosphite, 2,2-methylenebis (4,6-di-tert-butylphenyl) octylphosphite, and other phosphorus-based antioxidants. May be used alone or in combination.

The phosphorus-based antioxidant is easily mixed uniformly with the phosphinic acid metal salt (B) and prevents decomposition, so that flame retardancy can be improved. In addition, the phosphorus-based antioxidant can prevent decomposition and decrease in molecular weight of the semi-aromatic polyamide (A), and can improve operability, moldability, and mechanical properties during melt processing.

The content of the phosphorus-based antioxidant is preferably 0.1 to 2% by mass, more preferably 0.1 to 1 part by mass, based on the entire resin composition. Since the content of the phosphorus-based antioxidant is 0.1 to 2% by mass, the mold during molding does not deteriorate the stability, moldability, and mechanical properties of the resin composition during extrusion. It is possible to improve the mold releasability from the mold, suppress the clogging of the mold gas vent port, and improve the continuous injection moldability.

The polyamide resin composition of the present invention may further contain other additives such as stabilizers, colorants, antistatic agents, and carbonization inhibitors, if necessary. Examples of the colorant include pigments such as titanium oxide, zinc oxide and carbon black, and dyes such as niglosin. Examples of the stabilizer include a hindered phenol-based antioxidant, a sulfur-based antioxidant, a light stabilizer, a heat stabilizer made of a copper compound, a heat stabilizer made of alcohols, and the like. 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-mentioned heat stabilizers.

The method for producing the resin composition of the present invention is not particularly limited, but is limited to semi-aromatic polyamide (A), phosphinic acid metal salt (B), metal carbonate (C), fatty acid barium salt (D), and hindered. A method in which a hydrazine-based compound (E) having a phenol structure, an aliphatic polyamide (F) added as needed, a reinforcing material (G), other additives, and the like are blended and melt-kneaded is preferable. Examples of the melt-kneading method include a method using a batch kneader such as lavender, 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 the region where the semi-aromatic polyamide (A) is melted and the semi-aromatic polyamide (A) is not decomposed. If the melt-kneading temperature is too high, not only the semi-aromatic polyamide (A) may be decomposed, but also the phosphinic acid metal salt (B) may be decomposed. Therefore, the melting point of the semi-aromatic polyamide (A) is set to Tm. Then, it is preferably (Tm-20 ° C.) to (Tm + 50 ° C.).

Examples of the method for processing the polyamide resin composition of the present invention into various shapes include a method of extruding the melt mixture into a strand shape into a pellet shape, a method of hot-cutting and underwater-cutting the melt mixture into a pellet shape, and a method of forming a pellet shape. Examples thereof include a method of extruding into a sheet and cutting, and a method of extruding into a block and crushing to form a powder.

Examples of the molding method of the polyamide resin composition of the present invention include an injection molding method, an extrusion molding method, a blow molding method, and a sintering molding method, which have a large effect of improving mechanical properties and moldability. The molding method is preferable.
The injection molding machine is not particularly limited, and examples thereof include a screw in-line type injection molding machine and a plunger type injection molding machine. The 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 and solidified in a predetermined shape, and then molded from the mold. Taken out. The resin temperature at the time of injection molding is preferably equal to or higher than the melting point (Tm) of the semi-aromatic polyamide (A), and more preferably lower than (Tm + 50 ° C.).
When the polyamide resin composition is heated and melted, it is preferable to use sufficiently dried polyamide resin composition pellets. If the polyamide resin composition pellet contains a large amount of water, it may foam in the cylinder of an injection molding machine, making it difficult to obtain an optimum molded product. The water 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 has excellent flame retardancy and can be molded while suppressing metal corrosiveness, and is used as a molded product for a wide range of applications such as automobile parts, electrical and electronic parts, miscellaneous goods, and civil engineering and construction supplies. can.
Examples of automobile parts include thermostat covers, IGBT module members of inverters, insulator members, exhaust finishers, power device housings, ECU housings, ECU connectors, motor and coil insulating materials, and cable covering materials. Electrical and electronic components include, for example, connectors, LED reflectors, switches, sensors, sockets, capacitors, jacks, fuse holders, relays, coil bobbins, breakers, electromagnetic switches, holders, plugs, portable personal computers, word processors, and other electrical equipment. Examples include housing components, resistors, ICs, and LED housings. Above all, the polyamide resin composition of the present invention is particularly excellent in flame retardancy, and therefore can be suitably used for electrical and electronic parts.

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

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

(1) Melting point Using a differential scanning calorimeter (DSC-7 type manufactured by PerkinElmer Co., Ltd.), the temperature is raised to 350 ° C at a temperature rising rate of 20 ° C./min, held at 370 ° C. for 5 minutes, and the temperature lowering rate is 20 ° C./min. The temperature was lowered to 0 ° C., and the temperature was further maintained at 0 ° C. for 5 minutes, and then the top of the heat absorption peak when the temperature was raised again at a heating rate of 20 ° C./min was defined as the melting point (Tm).

(2) Melt flow rate (MFR)
According to JIS K7210 (melting point + 15 ° C.), the measurement was carried out under a load of 1.2 kgf.
The MFR can be used as an index of molding fluidity, and the higher the MFR value, the higher the fluidity.

(3) Mechanical Properties The polyamide resin composition is injection molded using an injection molding machine (FANUC S2000i-100B type) under the conditions of cylinder temperature (melting point + 15 ° C.) and mold temperature (melting point-185 ° C.). Then, a test piece (dumbbell piece) was prepared.
Using the obtained test piece, bending strength and flexural modulus were measured according to ISO178.
As for the bending strength and flexural modulus, the larger the numerical value, the better the mechanical properties.

(4) The flame-retardant polyamide resin composition is injection-molded using an injection molding machine (CND15 manufactured by Niigata Machine Techno Co., Ltd.) under the conditions of cylinder temperature (melting point + 15 ° C.) and mold temperature (melting point-185 ° C.). A test piece of 5, 5 inch (127 mm) × 1/2 inch (12.7 mm) × 1/32 inch (0.79 mm) was prepared.
Using the obtained test pieces, flame retardancy was evaluated according to the UL94 (standard defined by US Under Writer's Laboratories Inc.) standard shown in Table 1. When none of the criteria was met, it was set as "not V-2".
The shorter the total residual flame time, the better the flame retardancy.

(5) Mold dirt Using an injection molding machine (α-100iA manufactured by FANUC), a shallow cup is used in 25 seconds per cycle under the conditions of cylinder temperature (melting point + 25 ° C) and mold temperature (melting point-185 ° C). A molded product having a shape (thickness: 1.5 mm, outer diameter: 40 mm, depth: 30 mm) was continuously molded for 500 shots. After the molding was completed, a gas vent having a depth of 4 μm and a width of 1 mm was visually confirmed, and mold contamination was evaluated according to the following criteria. ◎ and ○ were accepted.
◎: No clogging seen ○: Partially clogged ×: Completely clogged

(6) Releasability By visually observing the presence or absence of marks on the protruding pins of the molded body on the 401st to 500th shots when continuously molding in (5) above, the number of molded bodies without pin marks was counted. The releasability was evaluated.
The number of molded products without pin marks is preferably 90 or more, and more preferably 95 or more.

(7) Metal Corrosion As shown in FIG. 1, a die (D) is attached to a twin-screw kneading extruder (EX) (PCM30 manufactured by Ikegai Corp.), and a metal plate (MP) (material) normally used as a steel material for an extruder. SUS630, 20 × 10 mm, thickness 5 mm, mass 7.8 g) were attached above and below the flow path (R) of the molten resin, and a gap of 1 mm 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 into the gap under the conditions of the extruder barrel set temperature (melting point + 15 ° C.) and discharge of 7 kg / h. After extrusion, the metal plate (MP) was removed and left in a furnace at 500 ° C. for 10 hours to remove the adhering resin, and then the mass was measured, and the metal corrosiveness was measured by the mass change before and after extrusion. The larger the weight change, the greater the metal corrosiveness.

(8) Reflow resistance Polyamide resin composition is injection molded using an injection molding machine J35AD (manufactured by Japan Steel Works, Ltd.) under the conditions of cylinder temperature (melting point + 15 ° C.) and mold temperature (melting point-185 ° C.). , 20 mm × 20 mm × 0.5 mm test piece and 20 mm × 20 mm × 2 mm test piece were prepared. The obtained test molded piece 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 oven at a rate of 100 ° C./min. The temperature was raised to 265 ° C. and held for 10 seconds.
In the test piece after heat treatment, when the area ratio of the blister (blister) generated on the surface of the test piece is 0% of the entire surface of the test piece, "◎" is given, and when it is larger than 0% and 25% or less, it is "◎". 〇 ”, a case of greater than 25% and 50% or less was evaluated as“ Δ ”, and a case of greater than 50% was evaluated as“ × ”.
It is preferable that the test piece after the heat treatment has no blister (blister) or melting on the surface.

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

(1) Semi-aromatic polyamide (A)
・ Semi-aromatic polyamide (A-1)
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 hypophosphate monohydrate as a polymerization catalyst. The mixture was placed in a ribbon blender type reactor, sealed with nitrogen, and heated to 170 ° C. with stirring at a rotation speed of 30 rpm. Then, while keeping the temperature at 170 ° C. and the rotation speed at 30 rpm, 4.98 kg of 1,10-decanediamine (DDA) heated to 100 ° C. as a diamine component using a liquid injection device was added to 2 . Addition was carried out continuously (continuous liquid injection method) over 5 hours to obtain a reaction product. The molar ratio of the raw material monomer is TPA: DDA: STA = 48.5: 49.6: 1.9 (the equivalent ratio of the functional groups of the raw material monomer is TPA: DDA: STA = 49.0: 50.0). : 1.0).
Subsequently, the obtained reaction product was polymerized by heating it in the same reactor under a nitrogen stream at 250 ° C. and a rotation speed of 30 rpm for 8 hours to prepare a semi-aromatic polyamide powder.
Then, the obtained semi-aromatic polyamide powder was made into strands using a twin-screw kneader, the strands were passed through a water tank to be cooled and solidified, and the strands were cut with a pelletizer to form semi-aromatic polyamides (A-1). Pellets were obtained.

-Semi-aromatic polyamides (A-2) to (A-5)
(A-2) to (A-5) were obtained in the same manner as in (A-1) except that the resin composition was changed as shown in Table 2.
Table 2 shows the resin composition and characteristic values of the above-mentioned polyamides (A-1) to (A-5).

(2) Metal phosphinic acid salt (B)
B-1: Aluminum diethylphosphinate (Exolit OP1230 manufactured by Clariant AG)

(3) Metal carbonate (C)
・ C-1: Calcium carbonate ・ C-2: Magnesium carbonate

(4) Fatty acid barium salt (D)
-D-1: Barium stearate (Ba-St P manufactured by Nitto Kasei Kogyo Co., Ltd.)
-D-2: Barium laurate (BS-3 manufactured by Nitto Kasei Kogyo Co., Ltd.)

(5) Hydrazine-based compound (E) having a hindered phenol structure
E-1: N, N'-bis [3- (3,5-di-tert-butyl-4-hydroxyphenyl) propionyl] hydrazine (CDA-10 manufactured by ADEKA CORPORATION)

(6) Aliphatic polyamide (F)
-F-1: Polyamide 66 (Unitika A125J)
F-2: Polyamide 46 (TW300 manufactured by DSM)

(7) Reinforcing material (G)
G-1: Glass fiber (03JAFT692 manufactured by Asahi Fiber Glass, average fiber diameter 10 μm, average fiber length 3 mm)
-G-2: Talc (Micro Ace K-1, manufactured by Nippon Talc, average particle size 8 μm)
-G-3: Talc (MSZ-C average particle size 11 μm surface-treated product manufactured by Japan Talc)
-G-4: Talc (MS-P average particle size 15 μm manufactured by Japan Talc)
-G-5: Talc (MS-KY average particle size 25 μm manufactured by Japan Talc)

(8) Triazole-based compound ・ H-1: 2-hydroxy-N-1H-1,2,4-triazole-3-yl-benzamide (CDA-1 manufactured by ADEKA CORPORATION)

Example 1
50 parts by mass of polyamide (A-1), 17 parts by mass of phosphinic acid metal salt (B-1), 1.5 parts by mass of metal carbonate (C-1), 1 part by mass of fatty acid barium salt (D-1), 0.5 parts by mass of hydrazine compound (E-1) having a hindered phenol structure was dry-blended, weighed using a loss-in-weight continuous quantitative feeder (CE-W-1 type manufactured by Kubota), and screw diameter. It was supplied to the main supply port of a 26 mm, L / D50 isodirectional twin-screw extruder (TEM26SS type manufactured by Toshiba Machine Co., Ltd.), and melt-kneaded. On the way, 30 parts by mass of the reinforcing material (G-1) was supplied from the side feeder, and further kneading was performed. After taking it into a strand shape from the die, it was passed through a water tank to be cooled and solidified, and it was cut with a pelletizer to obtain a polyamide resin composition pellet. The barrel temperature of the extruder was set (melting point −5 to + 15 ° C.), screw rotation speed 250 rpm, and discharge rate 25 kg / h.

Examples 2-31, Comparative Examples 1-14
The same operation as in Example 1 was carried out except that the composition of the polyamide resin composition was changed as shown in Tables 3 and 4, to obtain polyamide resin composition pellets.

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

In order to satisfy the requirements of the present invention, the resin compositions of Examples 1 to 31 have excellent flame retardancy, high mechanical properties, and suppressed metal corrosiveness at high temperatures. Further, the resin compositions of Examples 1 to 31 all have reflow resistance, and in any of the resin compositions, blister (blister) is generated or melted in a test piece of 20 mm × 20 mm × 0.5 mm. Etc. were not seen.
From the comparison of Examples 1 to 5, Examples 1, 2, 4 and 5 containing a monocarboxylic acid having a molecular weight of 140 or more as the monocarboxylic acid component of the polyamide to be used have less mold stain and are released from the mold. The sex was excellent. From the comparison between Example 1 and Example 3, Example 1 using an aliphatic monocarboxylic acid as a monocarboxylic acid component has a higher releasability than Example 3 using an aromatic monocarboxylic acid. It was excellent. From the comparison between Example 1 and Example 2, Example 1 using 1,10-decanediamine has more mechanical properties than Example 2 using 1,9-nonanediamine as the aliphatic diamine component. Was excellent.
In Examples 1 to 11-14, the flame retardancy was improved by increasing the content of the hydrazine-based compound having a hindered phenol structure. As will be described later, Comparative Example 10 was excellent in flame retardancy but extremely highly corrosive to metal by containing 32% by mass of the metal phosphinic acid salt. The flame retardancy similar to the flame retardancy obtained in Comparative Example 10 is obtained by containing a hydrazine-based compound having a hindered phenol structure even when the content of the phosphinic acid metal salt is reduced to 30% by mass. In the obtained (Example 8) example containing a hydrazine-based compound having a hindered phenol structure, the content of the phosphinic acid metal salt can be reduced, and metal corrosiveness can be suppressed. rice field.
In Examples 1 and 15 to 17, the effect of suppressing metal corrosiveness was improved by increasing the content of the metal carbonate. However, by increasing the content of the metal carbonate, a decrease in flame retardancy was also observed. In Examples 1, 19 to 21, an improvement in the effect of suppressing metal corrosiveness was observed by increasing the content of the fatty acid barium salt. However, by increasing the content of the fatty acid barium salt, a decrease in mechanical properties was also observed.
From the comparison between Examples 1 and 23, Example 1 using glass fiber as a reinforcing material was superior in mechanical properties to Example 23 using plate-shaped talc.
From the comparison of Examples 1, 24 and 25, the effect of improving the fluidity and further suppressing the metal corrosiveness was observed by containing the aliphatic polyamide. In Examples 24 and 25 containing the aliphatic polyamide, blister (blister) was generated in the test piece of 20 mm × 20 mm × 2 mm, and a decrease in reflow resistance was observed, but in Examples 27 to 31 By containing talc having an average particle size in the range of 10 to 30 μm as a reinforcing material, a decrease in reflow resistance was suppressed.

Comparative Example 1 containing no phosphinic acid metal salt was inferior in flame retardancy, and Comparative Example 2 containing a phosphinic acid metal salt was significantly improved in flame retardancy but significantly more corrosive to metal. .. Comparative Example 3 containing a metal carbonate and Comparative Example 4 containing a fatty acid barium salt suppressed metal corrosiveness, and Comparative Example 5 containing a metal carbonate and a fatty acid barium salt significantly suppressed metal corrosiveness. However, the flame retardancy was significantly reduced.
In Comparative Example 6, since the content of the hydrazine compound having a hindered phenol structure was large, the mechanical properties were lower than those in Examples 1 and 11 to 14, and the effect of improving flame retardancy was saturated. In Comparative Example 7, a triazole compound having a hydrazine structure in the ring but not having a hindered phenol structure was used instead of the hydrazine compound having a hindered phenol structure, and therefore, as compared with Example 1. , The effect of improving flame retardancy was not observed.
Comparative Examples 8 and 9 were inferior in flame retardancy because they did not contain or contained a small amount of the metal phosphinic acid salt. In Comparative Example 10, since the content of the metal salt of phosphinic acid was large, the flame retardancy was excellent, but the metal corrosiveness was remarkably high.
In Comparative Example 11, since it did not contain a metal carbonate, the metal corrosiveness was remarkable. In Comparative Example 12, since the content of the metal carbonate was high, the flame retardancy was lower than that in Examples 1 and 15 to 17, and the effect of suppressing metal corrosiveness was saturated. In Comparative Example 13, since the fatty acid barium salt was not contained, the metal corrosiveness was remarkable. In Comparative Example 14, since the content of the fatty acid barium salt was high, the flame retardancy was lower than that in Examples 1 and 19 to 21, and the effect of suppressing metal corrosiveness was saturated.

EX: Biaxial kneading extruder D: Die MP: Metal plate R: Flow path of molten resin

Claims (9)

Semi-aromatic polyamide (A) having a melting point of 300 to 350 ° C. is 20 to 80% by mass, phosphinic acid metal salt (B) is 5 to 30% by mass, and metal carbonate (C) is 0.1 to 8% by mass. A polyamide resin composition comprising 0.01 to 3% by mass of a fatty acid barium salt (D) and 0.01 to 5% by mass of a hydrazine-based compound (E) having a hindered phenol structure. The polyamide resin composition according to claim 1, wherein the phosphinic acid metal salt (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 independently represent an alkyl group or a phenyl group having 1 to 16 carbon atoms in a linear or branched chain, respectively. R ³ is a linear or branched chain or branched chain. It 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. M represents a calcium ion, an aluminum ion, a magnesium ion or a zinc ion. Is 2 or 3. n, a, b are integers satisfying the relational expression of 2 × b = n × a.) The polyamide resin composition according to claim 1 or 2, wherein the metal constituting the metal carbonate (C) is at least one selected from the group consisting of calcium, magnesium, sodium, and lithium. Claims 1 to 1, wherein the fatty acid constituting the fatty acid barium salt (D) is at least one selected from the group consisting of lauric acid, stearic acid, 12-hydroxystearic acid, behenic acid, and montanic acid. The polyamide resin composition according to any one of 3. The polyamide resin composition according to any one of claims 1 to 4, wherein the hydrazine-based compound (E) having a hindered phenol structure is a compound represented by the following formula (III).

The polyamide resin composition according to any one of claims 1 to 5, further comprising an aliphatic polyamide (F) having a melting point of 200 to 300 ° C. The polyamide resin composition according to any one of claims 1 to 6, further containing 5 to 60% by mass of the reinforcing material (G). The polyamide resin composition according to claim 7, wherein the reinforcing material (G) contains talc having an average particle size of 10 to 30 μm. A molded product obtained by molding the polyamide resin composition according to any one of claims 1 to 8.

Images