JPH1143602A - Polyamide resin composition - Google Patents

Abstract

PROBLEM TO BE SOLVED: To obtain a resin composition which can give moldings improved in thermal properties, surface appearance, mechanical properties and flame retardancy by mixing a resin component comprising a polyamide resin or comprising a polyamide resin and other thermoplastic resins with a salt of polyphosphoric acid with melam or a melam derivative and an inorganic filler in a specified ratio. SOLUTION: There is provided a composition prepared by mixing 100 pts.wt. resin component with 1-50 pts.wt. salt comprising polyphosphoric acid and melam or a melam derivative and 0-300 pts.wt. inorganic filler. The polyamide resin is desirably a polyamide resin obtained from xylylenediamine and an ω-linear aliphatic dibasic acid or a combination thereof with nylon 66 and/or nylon 6. The thermoplastic resin other than the polyamide resin is desirably a polyphenylene ether resin (PPE resin). The polyphenylene ether resin is a polymer having a main chain comprising structural units of the formula (wherein R<1> is a 1-3 C alkyl; and R<2> and R<3> are each H or a 1-3 C alkyl).

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

The present invention relates to a polyamide resin composition, and more particularly, to a flame-retardant polyamide resin composition.

[0002]

2. Description of the Related Art Heretofore, several methods have been proposed for flame retarding polyamides, but a general method is to add and mix a flame retardant to polyamide. Halogen-based flame retardants, nitrogen-based compounds, metal-containing compounds, etc. are known as flame retardants, but when halogen-based flame retardants are used, the safety of gas generated during combustion has been questioned. When a metal compound is used, the flame retarding effect is insufficient.

With respect to nitrogen compounds, for example, JP-A-50-105744 and JP-A-53-31759 disclose flame retardant compounds by adding triazine compounds such as melamine, cyanuric acid and melamine cyanurate to polyamide. A technique for improving the performance is disclosed. However, even in these methods, when an inorganic filler, especially a fibrous substance such as glass fiber, is blended with polyamide, there is a disadvantage that the flame retardancy is reduced due to the action of a candle core. Sublimation causes a so-called plate-out phenomenon that adheres to a mold, etc., which results in poor mold release, rough appearance of the molded product, or a blooming phenomenon in which part of the flame retardant precipitates on the surface of the molded product. There was a drawback to do.

[0004] For example, JP-A-53-49054 discloses a flame-retardant composition containing melamine phosphate, but a polyamide obtained by simply adding a salt of phosphoric acid and melamine. Owing to poor compatibility with water, there are drawbacks such as difficulty in workability during extrusion kneading and impairing the appearance of molded articles.

[0005]

SUMMARY OF THE INVENTION An object of the present invention is to provide a polyamide resin composition which is excellent in thermal properties, surface appearance, mechanical properties and flame retardancy in addition to the inherent properties inherent in polyamide. Is to provide.

[0006]

SUMMARY OF THE INVENTION The present invention has been made to solve the above-mentioned problems, and its gist is that a resin component composed of a polyamide resin or a polyamide resin and a thermoplastic resin other than the polyamide resin has a weight of 100%. For the department,
The polyamide resin composition comprises 1 to 50 parts by weight of a salt comprising polyphosphoric acid and melam or a melam derivative and 0 to 300 parts by weight of an inorganic filler.

Hereinafter, the present invention will be described in detail. As the polyamide resin in the present invention, nylon 6, nylon 66, nylon 69, nylon 610, nylon 6
12, nylon 12, polyamide resin (hereinafter also referred to as MX nylon) obtained from xylylenediamine and α, ω-linear aliphatic dibasic acid, and a mixture thereof, but are not limited thereto. Not something. As the polyamide resin, preferably, a polyamide resin obtained from xylylenediamine and α, ω-linear aliphatic dibasic acid, or a resin obtained from xylylenediamine and α, ω-linear aliphatic dibasic acid A resin of polyamide resin and nylon 66 and / or nylon 6 is mentioned, and a resin of MX nylon and nylon 66 is more preferable.

When the polyamide resin is a resin of MX nylon and nylon 66 and / or nylon 6,
The mixing ratio of nylon 66 and / or nylon 6 to 100 parts by weight of MX nylon is 0 to 100 parts by weight,
Preferably it is 0 to 80 parts by weight.

The thermoplastic resin other than the polyamide resin in the present invention includes polystyrene resin, ABS resin,
ES resin, AS resin, olefin resin, methacrylic resin, polycarbonate resin, polyacetal resin, polyphenylene ether resin (PPE resin), modified PPE resin, polyester resin, polysulfone resin, polyimide resin, polyphenylene sulfide resin, polyarylate resin, polyether Sulfone resin, polyetherketone resin, polyetheretherketone resin, polyestercarbonate resin, amorphous polyamide resin, thermoplastic resin such as liquid crystal polymer, alloy resin composition composed of two or more of these resins, and the like, preferably Is a polyphenylene ether resin (PPE resin).
If necessary, inorganic and organic fibrous fillers, fillers, stabilizers, ultraviolet absorbers, dyes and pigments can be added to these materials.

When the resin component in the present invention comprises a polyamide resin and a thermoplastic resin other than the polyamide resin,
The ratio of the polyamide resin to the thermoplastic resin other than the polyamide resin is preferably 99/1 to 1/99, more preferably 90/10 to 10/90, and further preferably 70/30 to 30/70. It is.

The polyphenylene ether resin is a polymer having a structural unit represented by the following general formula (1) in the main chain, and may be a homopolymer, a copolymer or a graft polymer.

[0012]

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In the formula, R ¹ is a lower alkyl group having 1 to 3 carbon atoms, and R ² and R ³ are a hydrogen atom or a lower alkyl group having 1 to 3 carbon atoms.

A specific example of the polyphenylene ether resin is poly (2,6-dimethyl-1,4-phenylene).
Ether, poly (2,6-diethyl-1,4-phenylene) ether, poly (2,6-dipropyl-1,4-phenylene) ether, poly (2-methyl-6-ethyl-)
1,4-phenylene) ether, poly (2-methyl-6)
-Propyl-1,4-phenylene) ether and the like, preferably, poly (2,6-dimethyl-1,4-phenylene) ether, 2,6 dimethylphenol / 2,
Examples include 3,6-trimethylphenol copolymers and graft copolymers obtained by grafting styrene onto these.

As a specific example of the polyphenylene ether resin, more preferably, a polyphenylene ether resin having improved compatibility (hereinafter sometimes referred to as modified PPE)
Is mentioned. The modified PPE is obtained by reacting PPE with an unsaturated carboxylic acid or an acid anhydride thereof.

When an unsaturated carboxylic acid anhydride is used for the modification of PPE, the unsaturated carboxylic acid anhydride and PPE are reacted in a melt-mixed state without a catalyst to form a modified PP.
E can be obtained. In this case, the method of melt mixing is not particularly limited, such as a kneader, a Banbury mixer, an extruder, etc. However, it is preferable to use an extruder in consideration of operability. As the acid anhydride of the unsaturated aliphatic carboxylic acid,
Examples thereof include maleic anhydride, itaconic anhydride and citraconic anhydride, and among them, maleic anhydride is particularly preferable.

The amount of the acid anhydride required for modifying the PPE is 0.01 to 10 parts by weight, preferably 0.1 to 3 parts by weight, particularly preferably 0.1 to 1 part by weight, based on 100 parts by weight of the PPE. Parts by weight. The use ratio of the acid anhydride is
With respect to 100 parts by weight of PPE, when the amount is 0.01 part by weight or less, the effect of improving the compatibility between PPE and nylon is small,
If a tough composition is difficult to obtain, and if the use ratio is 10 parts by weight or more, excess acid anhydride is thermally decomposed, resulting in practical inconvenience such as reduced heat resistance and poor appearance.

When an unsaturated aliphatic carboxylic acid is used for the modification of PPE, a radical generator such as benzoyl peroxide, dicumyl peroxide and cumene hydroperoxide can be used as a catalyst, if necessary. . The usage ratio of the unsaturated carboxylic acid necessary for the modification of PPE is 0.01 to 10 parts by weight based on 100 parts by weight of PPE.

In the present invention, the salt comprising polyphosphoric acid and melam or a melam derivative is preferably a compound represented by the following general formula (2).

[0020]

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In the formula, R ⁴ and R ⁵ each represent a hydrogen atom, a cyano group or a guanyl group, preferably a hydrogen atom.

The salt of polyphosphoric acid and melam or a melam derivative preferably has a phosphorus content of 5 to 15% by weight.
It is. When the phosphorus content is less than 5% by weight, the flame retardancy decreases, and when the phosphorus content exceeds 15% by weight, the hygroscopicity increases. The phosphorus content of the salt comprising polyphosphoric acid and melam or a melam derivative is preferably from 7 to 12% by weight. The average particle size of the salt comprising polyphosphoric acid and melam or a melam derivative is preferably 50 μm or less. Average particle size is 5
If it exceeds 0 μm, the dispersibility in the polyamide resin is reduced, and the appearance of the molded product is likely to be affected. The average particle size of the salt composed of polyphosphoric acid and melam or a melam derivative,
More preferably, it is 0.1 to 30 μm. Specific examples of the salt comprising polyphosphoric acid and melam or a melam derivative include, for example, melam polyphosphate, cyanomelam polyphosphate, guanyl melam polyphosphate, and the like, and preferably, melam polyphosphate. .

The salt comprising polyphosphoric acid and melam or a melam derivative is a salt obtained by a neutralization reaction between phosphoric acid and melam or a melam derivative. For example, phosphoric acid is added to an aqueous solution of melam obtained from melamine. And then the reaction product is obtained by filtration, washing and drying, the product being a white solid,
Usually, it is used by pulverizing it into fine powder.

Melam or a melam derivative generally has better thermal stability than melamine, and is less likely to sublime at the molding temperature of a polyamide resin. As the phosphoric acid, a known phosphoric acid is used, and specific examples thereof include orthophosphoric acid, phosphorous acid, and hypophosphorous acid. Preferably, orthophosphoric acid that can be industrially mass-produced is used. Further, in order to improve the solubility of orthophosphoric acid in water and the hygroscopicity, it is preferable that a part of orthophosphoric acid is condensed phosphoric acid such as pyrophosphoric acid and metaphosphoric acid.

A salt comprising polyphosphoric acid and melam or a melam derivative can also be obtained by the following method. For example, a salt obtained by a neutralization reaction between phosphoric acid and melamine or a melamine derivative can be obtained by baking at 300 to 400 ° C. for several hours. At this time, depending on the calcination time or calcination temperature, the deammonification reaction of melam or the melam derivative partially proceeds, and a salt composed of polyphosphoric acid and melem or the melem derivative represented by the following formula may be generated. Since a small amount can be used without particularly affecting flame retardancy and mechanical properties, it may be contained in a salt composed of polyphosphoric acid and melam or a melam derivative. The products are all white solids and are usually used after being ground to a fine powder.

[0026]

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In the formula, R ⁶ represents a hydrogen atom, a cyano group or a guanyl group, preferably a hydrogen atom.

The amount of the salt comprising polyphosphoric acid and melam or a melam derivative is 1 to 50 parts by weight based on 100 parts by weight of a resin component comprising a polyamide resin or a thermoplastic resin other than a polyamide resin and a polyamide resin. If the compounding amount of the salt comprising polyphosphoric acid and melam or a melam derivative is less than 1 part by weight, the flame retardancy is insufficient, and
If the amount exceeds 0 parts by weight, the mechanical properties deteriorate. The compounding ratio of the salt composed of polyphosphoric acid and melam or a melam derivative is preferably 5 to 40 parts by weight, based on 100 parts by weight of a resin component composed of a polyamide resin or a thermoplastic resin other than the polyamide resin and polyamide resin. Preferably it is 8 to 30 parts by weight.

As the inorganic filler, known inorganic fillers can be used, and the shape is not particularly limited.
Any of a plate shape, a needle shape, a spherical shape, a powder, and the like may be used. Examples of the inorganic filler include glass fiber, carbon fiber, talc, mica, glass flake, wollastonite, potassium titanate, magnesium sulfate, sepiolite, zonolite, aluminum borate, glass beads,
Balloon, calcium carbonate, silica, kaolin, clay, titanium oxide, barium sulfate, zinc oxide, magnesium hydroxide and the like, and can be used alone or as a mixture of two or more, preferably glass fiber, Talc and calcium carbonate.

The amount of the inorganic filler is from 0 to 300 parts by weight, preferably from 5 to 300 parts by weight, based on 100 parts by weight of the resin component composed of the polyamide resin or the thermoplastic resin other than the polyamide resin. is there. When the inorganic filler is blended, if the blending amount of the inorganic filler is less than 5 parts by weight, the effect of improving the mechanical strength and thermal properties is small, and if it exceeds 300 parts by weight, the processability is reduced. The blending amount of the inorganic filler is preferably 10 to 250 parts by weight, more preferably 50 to 150 parts by weight, based on 100 parts by weight of a resin component composed of a polyamide resin or a thermoplastic resin other than a polyamide resin and a polyamide resin. .

In the polyamide resin composition of the present invention, in addition to the above components, various additives generally used for polymer materials, such as stabilizers, face dyes, release agents,
A lubricant, a nucleating agent, a weather resistance improving agent and the like can be appropriately compounded. As a method for producing the polyamide resin composition in the present invention, a usual method can be adopted, and there is no particular limitation. For example, a polyamide resin, a thermoplastic resin other than the polyamide resin, and optionally, an inorganic filler and various additives are melted in an arbitrary order using a conventional device, for example, a vented extruder or a device similar thereto. The method of kneading is mentioned.

Hereinafter, the present invention will be described in more detail with reference to examples, but the present invention is not limited to the following examples unless it exceeds the gist of the present invention.

EXAMPLES The raw materials used in the examples and comparative examples are as follows. (1) Nylon MXD6: poly (meta-xylylene adipamide), manufactured by Mitsubishi Gas Chemical Company, Inc., relative viscosity (measured at a temperature of 25 ° C. using 98% sulfuric acid as a solvent) 2.14. (2) Nylon 66: relative viscosity 2.25. (3) Nylon 6: relative viscosity 2.30.

(4) Modified PPE: To 5 kg of PPE (manufactured by Mitsubishi Gas Chemical Co., Ltd., intrinsic viscosity 4.45), 50 g of maleic anhydride was added and mixed with a super mixer for 3 minutes. Modified PPE modified with maleic anhydride by kneading under heating and melting at 300 ° C. with a twin screw extruder. (5) Glass fiber: chopped strand, trade name CS
03-JAFT2, length 3 mm, manufactured by Asahi Fiber Glass Co., Ltd. (6) Calcium carbonate: trade name NS-100, manufactured by Nitto Powder Chemical Industry Co., Ltd.

(7) Melam polyphosphate: Phosphorus content: 9.8% by weight, average particle size: 1.8 μm, manufactured by Nissan Chemical Industries, Ltd. (8) (Melam / Melem) polyphosphate mixture:
Melam / Melem = 9/1 (molar ratio), phosphorus content 12% by weight, average particle diameter 10 μm, manufactured by Nissan Chemical Industries, Ltd. (9) Flame retardant a: melamine phosphate, Nissan Chemical Industries, Ltd.
Made. (10) Flame retardant b: melamine cyanurate, trade name MC
440, manufactured by Nissan Chemical Industries, Ltd. (11) Flame retardant c: magnesium hydroxide, trade name Kisuma 5E, manufactured by Kyowa Chemical Co., Ltd.

In Examples and Comparative Examples, tests for bending strength, flammability, and mold contamination were performed as follows. (12) Flame retardancy: 5 inches long and 1 width from the resin composition
A combustion test piece having a thickness of 1/2 inch and a thickness of 1/16 inch was molded using an injection molding machine at a resin temperature of 260 ° C. and a mold temperature of 130 ° C.
Molded. The flame retardancy was determined for this test piece by Subject as determined by Underwriters Laboratories, USA.
The test was performed according to the t94 (UL-94) standard.

(13) Bending strength: A bending test piece having a length of 5 inches, a width of 1/2 inch and a thickness of 1/4 inch was formed from the resin composition at a resin temperature of 260 ° C. and a mold temperature of 130 ° C. Flexural strength was measured according to ASTM D790. (14) Mold contamination test: Primary injection pressure 500 kgf / c
m ² , injection speed 20 mm / s, holding pressure 0 kgf / cm ² , injection time 3 seconds, molding temperature 270 ° C, mold temperature 130 ° C, cooling time 8 seconds, short shot of 1.5 inch disk , And the mold surface after the molding was visually observed. The state of the surface was evaluated on the following four levels.
：: Almost no mold contamination is observed, ○: Slight mold contamination is observed, Δ: Die contamination is observed, ×: Die contamination is noticeably observed.

Examples 1-2 Nylon MXD6, nylon 66, glass fiber and melam polyphosphate are weighed as shown in Table 1, mixed with a tumbler, and then melted at 270 ° C. using a vented extruder. After kneading, the mixture was extruded into a string, cooled in a water bath, cut and dried to form pellets. Table 1 shows the evaluation results of the obtained materials.

Comparative Example 1 Nylon MXD6, Nylon 66 and glass fiber were weighed as shown in Table 1, mixed with a tumbler, melted and kneaded at 270 ° C. using a vented extruder, and then formed into a string. After extrusion, cooling in a water bath, cutting and drying, pellets were formed. Table 1 shows the evaluation results of the obtained materials. [Comparative Examples 2 to 4] Nylon MXD6, Nylon 66, glass fiber and flame retardants a to c were weighed as shown in Table 1, and
After mixing with a tumbler, use a vent-type extruder at 270 ° C.
After extruding into a string, the mixture was cooled in a water bath, cut and dried to form pellets. Table 1 shows the evaluation results of the obtained materials.

[0039]

[Table 1]

Examples 3 and 4 Nylon MXD6, Nylon 66, Nylon 6, glass fiber, calcium carbonate and melam polyphosphate are weighed as shown in Table 2 and mixed with a tumbler. Use 27
After melt-kneading at 0 ° C., the mixture was extruded into a string, cooled in a water bath, cut and dried to form a pellet. Table 2 shows the evaluation results of the obtained materials.

[Comparative Examples 5 to 7] Nylon MXD6, Nylon 66, Nylon 6, glass fiber, calcium carbonate and flame retardants a to c were weighed as shown in Table 2 and tumbled.
After melt-kneading at 270 ° C. using a vented extruder, the mixture was extruded into a string, cooled in a water bath, cut and dried to form pellets. Table 1 shows the evaluation results of the obtained materials.
It is shown in FIG.

[0042]

[Table 2]

[Examples 5 to 6] Nylon MXD6, Nylon 66, modified PPE, glass fiber and melam polyphosphate are weighed as shown in Table 3, mixed with a tumbler, and mixed with a vented extruder. After melt-kneading at a temperature of ° C, the mixture was extruded into a string, cooled in a water bath, cut and dried to form pellets. Table 3 shows the evaluation results of the obtained materials.

Comparative Examples 8 to 10 Nylon MXD6, Nylon 66, modified PPE, glass fiber and flame retardant a
c was weighed out as shown in Table 3, mixed with a tumbler, melt-kneaded at 270 ° C using a vented extruder, extruded into a string, cooled in a water bath, cut and dried to form pellets. did. Table 3 shows the evaluation results of the obtained materials.

[0045]

[Table 3]

[Examples 7 to 9] Nylon MXD6, Nylon 66, Nylon 6, modified PPE, glass fiber and (melam / melem) polyphosphate are weighed as shown in Table 4, mixed with a tumbler, and then vented. After melt-kneading at 270 ° C. using a type extruder, the mixture was extruded in a string form, cooled in a water bath, cut and dried to form pellets. Table 4 shows the evaluation results of the obtained materials.

[0047]

[Table 4]

[0048]

The polyamide resin composition of the present invention is excellent in thermal properties, surface appearance, mechanical properties, and flame retardancy in addition to the excellent properties inherent in polyamide.
Further, the gas generated during combustion is excellent in safety and can be used for various molded products. In particular, it is excellent in bending strength and flexural modulus and has mechanical properties that can substitute for metal, so it can be used for mechanical parts such as OA equipment that requires high mechanical properties and is extremely useful. . Further, the polyamide resin composition of the present invention is excellent in mold contamination during molding, and is also excellent in moldability, which is advantageous for producing various molded products.

──────────────────────────────────────────────────の Continued on the front page (51) Int.Cl. ⁶ Identification code FI C08L 101: 00) (C08L 77/00 71:12) (C08K 13/02 3:00 5:52) (C08L 71/12 77) : 00) (C08L 101/00 77:00)

Claims (6)

[Claims] 1. A resin component 1 comprising a polyamide resin or a thermoplastic resin other than a polyamide resin and a polyamide resin.
1 to 50 parts by weight of a salt comprising polyphosphoric acid and melam or a melam derivative and 0 to 3 parts by weight of inorganic filler
A polyamide resin composition containing 00 parts by weight. 2. A polyamide resin obtained from xylylenediamine and an α, ω-linear aliphatic dibasic acid, or a polyamide resin obtained from xylylenediamine and an α, ω-linear aliphatic dibasic acid. Polyamide resin and nylon 6
The polyamide resin composition according to claim 1, which is a resin with nylon 6 and / or nylon 6. 3. A thermoplastic resin other than a polyamide resin,
The polyamide resin composition according to claim 1, wherein the polyamide resin composition is a polyphenylene ether resin. 4. The polyamide resin composition according to claim 1, wherein the inorganic filler is an inorganic filler selected from the group consisting of glass fiber, calcium carbonate, and talc. 5. The polyamide resin composition according to claim 1, wherein the salt comprising polyphosphoric acid and melam or a melam derivative has a phosphorus content of 5 to 15%. 6. The polyamide resin composition according to claim 1, wherein the salt composed of polyphosphoric acid and melam or a melam derivative has an average particle diameter of 50 μm or less.