JPH05214246A - Flame-retarding polyamide resin composition - Google Patents

Abstract

PURPOSE:To provide the title composition having good flowability and mold releaseability, a shortened molding cycle time, and a markedly improved productivity and being capable of giving a molding having good appearance, excellent mechanical properties and flame retardancy. CONSTITUTION:The title composition comprises 100 pts.wt. polyamide resin, 0.001-10 pts.wt. polyamide oligomer terminated with a 6-30C hydrocarbon group and has a molecular weight of 5000 or below and 1-25 pts.wt. triazine flame retardant.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a flame-retardant polyamide resin composition comprising a polyamide resin, a polyamide oligomer and a triazine flame retardant, which is excellent in flame retardancy, fluidity, mold releasability and mechanical properties. is there.

[0002]

As a flame-retardant polyamide resin composition,
Conventionally containing melamine (Japanese Patent Publication No. 49-171)
4) containing cyanuric acid (Japanese Patent Laid-Open No. 50-105)
744) or those containing both melamine and cyanuric acid (Japanese Patent Laid-Open No. 51-54655) and the like are used in a wide range of industrial fields such as electric / electronic parts, automobile parts and machine parts. However, due to recent demands for higher performance and higher productivity of parts, shortening of molding cycle and further improvement of mechanical properties are desired.

As a method for improving it, there has been proposed a method of blending melamine cyanurate and stearyl stearate in a polyamide resin (Japanese Patent Laid-Open No. 58-27744), which improves releasability while maintaining flame retardancy. be able to.

[0004]

However, the above-mentioned method aimed at improving the mold releasability and plasticizing property not only lowers the flame retardancy by adding the mold releasing agent but also reduces the molding cycle time. Shortening and improvement of releasability are still unsatisfactory, and there are problems such as deterioration of mechanical properties represented by tensile strength and elongation.

Therefore, the object of the present invention is to obtain a flame-retardant polyamide resin composition having excellent mechanical properties and flame retardancy while further improving the fluidity and releasability.

[0006]

That is, the present invention is as follows.
(A) With respect to 100 parts by weight of the polyamide resin, (B) a molecular weight of 5,000 having a hydrocarbon group having 5 to 30 carbon atoms at the end.
A flame-retardant polyamide resin composition comprising 0.001 to 10 parts by weight of the following polyamide oligomer and 1 to 25 parts by weight of a (C) triazine-based flame retardant is provided.

That is, the feature of the present invention is to find a material which is improved in flame retardancy, fluidity and releasability and which is excellent in mechanical properties by comprising a polyamide, a specific polyamide oligomer and a triazine flame retardant. There is a point.

The present invention will be described in detail below.

As the polyamide used in the present invention,
Examples thereof include ring-opening polymerization products of cyclic lactams, polycondensation products of aminocarboxylic acids, polycondensation products of dibasic acids and diamines, and specifically, nylon 6, nylon 4.6, nylon 6.6, nylon. 6/10, Nylon 6/12, Nylon 11, Nylon 12 and other aliphatic polyamides, poly (meta-xylene adipamide), poly (hexamethylene terephthalamide), poly (hexamethylene isophthalamide), poly (tetramethylene isophthal Examples thereof include aliphatic-aromatic polyamides such as amides), and copolymers and mixtures thereof. Particularly suitable polyamides for the present invention include nylon 6, nylon 6.6, and nylon 6/6/6.

The degree of polymerization of the polyamide used here is not particularly limited, but the relative viscosity measured at 25 ° C. in 98% sulfuric acid concentration of 1% according to JIS K6810 is 1.7 or more from the viewpoint of polymerization stability, and the processability is high. From the point, it is less than 4.5, particularly 2.0 or more and less than 4.0, further 2.0 or more and
It is preferably less than 5. Polymerization method of the polyamide used in the present invention is not particularly limited, melt polymerization, interfacial polymerization,
Solution polymerization, bulk polymerization, solid phase polymerization, and a combination of these methods can be used. Usually, melt polymerization is preferably used.

The terminal and molecular weight-limited polyamide oligomer used in the present invention is obtained by polycondensation of lactam, aminocarboxylic acid and dibasic acid / diamine together with a molecular weight regulator.

The raw materials for the polyamide portion of these include pyrrolidone, piperidone, caprolactam, enanthlactam, capryllactam, lauryllactam,
Glycine, β-alanine, 4-aminobutyric acid, 5-aminopentanoic acid, 6-aminocaproic acid, 7-aminoheptanoic acid, 9-aminonanoic acid, 11-aminoundecanoic acid, malonic acid, succinic acid, adipic acid, pimerine acid,
Azelaic acid, phthalic acid, terephthalic acid, cyclohexanedicarboxylic acid, ethylenediamine, 1,3 (1,2)
-Diaminopropane, tetraethylenediamine, hexamethylenediamine, nanomethylenediamine, undecamethylenediamine, dodecamethylenediamine, metaxylylenediamine, paraxylylenediamine, isophoronediamine, and the like, and one or more of these may be mentioned. To use.

Among the polyamide oligomers obtained from these raw materials, the polyamide oligomer obtained by the combination of dibasic acid / diamine is more preferable, and further, both or one of the dibasic acid and / or diamine has 4 or less carbon atoms. preferable.

The hydrocarbon group having 5 to 30 carbon atoms at the end of the polyamide oligomer of the present invention includes hexyl group, heptyl group, octyl group, ethylhexyl group, nonyl group, decyl group, undecyl group, dodecyl group and tetradecyl group. Group, pentadecyl group, hexadecyl group, octadecyl group, eicosyl group, cyclohexyl group, phenyl group,
Typical examples include a toluyl group, a benzyl group and a β-phenylethyl group. These hydrocarbon groups are introduced by adding a carboxylic acid and / or an amine as a molecular weight modifier during the production of the polyamide oligomer. Specific examples of these molecular weight regulators include enanthic acid, caprylic acid, undecanoic acid, lauric acid, palmitic acid, stearic acid, oleic acid, linoleic acid, cyclohexanecarboxylic acid, benzoic acid, toluic acid, phenyl. Acetic acid, hexylamine, octylamine, nonylamine, decylamine, undecylamine, octadecylamine, cyclohexylamine, benzylamine, β-
Examples thereof include phenethylamine.

The polyamide oligomer of which the terminal and the molecular weight are limited according to the present invention is obtained by heating the above-mentioned raw material for the polyamide moiety and the molecular weight modifier together. The heating temperature is usually 160 to 320 ° C, preferably 180 to 300 ° C.

Further, although the effect of the present invention is maximized when the hydrocarbon groups are added to all terminals of the polyamide oligomer, it is not always necessary that the hydrocarbon groups are added to all terminals. The effect of the present invention can be obtained if a hydrocarbon group is added to at least 40% or more of the ends of the polyamide oligomer, preferably 50% or more, and more preferably 60% or more of the ends. The polyamide oligomer used in the present invention has a molecular weight of 5000 or less, preferably 3000 or less, and more preferably 1500 or less.
When the molecular weight exceeds 5,000, not only the production of polyamide oligomer becomes difficult, but also the effect of improving the releasability and physical properties cannot be obtained. The lower limit of the molecular weight is not particularly limited, but it is preferable that at least 3 or more amide bonds are present in the molecule.

In the present invention, the blending ratio of the polyamide oligomer whose terminal and molecular weight are limited is 0.001 to 10 parts by weight, preferably 0.005 to 5 parts by weight, and more preferably 100 parts by weight of the polyamide resin. 0.0
It is used in the range of 1 to 2 parts by weight. When it is less than 0.001 part by weight, the effect of improving various properties is not observed, and when it exceeds 10 parts by weight, fluidity and mold releasability are improved, but gas is generated during molding and a molded product is obtained. The appearance is deteriorated and flame retardancy and mechanical properties are deteriorated, which is not preferable.

A bisamide represented by ethylenebisstearylamide has been conventionally used as a release agent or a lubricant. When the bisamides are blended with a polyamide resin and a triamine-based flame retardant, the releasability is improved, but the flame retardancy, fluidity, tensile elongation, etc. are deteriorated.

That is, although the terminal and molecular weight limited polyamide oligomer of the present invention has a similar molecular structure to ethylenebisstearylamide,
The effect is significantly different.

Therefore, in the present invention, an amide of a dibasic acid such as N, N'-bisstearyl succinamide and a monoamine and an amide of a diamine and a monocarboxylic acid such as ethylene stearyl amide have terminal and molecular weights. It is not included in the restricted polyamide oligomers.

Examples of the triazine flame retardant used in the present invention include melamines, cyanuric acids, and melamine cyanuric acids. These triazine-based flame retardants can be used alone or in combination. Below, these compounds are demonstrated concretely.

The melamines are melamine, melamine derivatives, compounds having a structure similar to melamine, or condensates of melamine, such as melamine, ammelide, ammeline, formoguanamine, guanylmelamine, cyanomelamine, arylguanamine, melam, Examples include melem and melon.

Cyanuric acids are cyanuric acid, isocyanuric acid and their derivatives, such as cyanuric acid, isocyanuric acid, trimethylcyanurate, trimethylisocyanurate, triethylcyanurate, triethylisocyanurate, tri (n-propyl) cyanurate. , Tri (n-propyl) isocyanurate, methylcyanurate, methylisocyanurate, diethylcyanurate, diethylisocyanurate and the like.

The melamine cyanuric acid is an equimolar reaction product of melamine and cyanuric acid, but it is not always an equimolar reaction product, and even if a part of the functional groups is in a free state, a substituent May be replaced with.

As the triazine-based flame retardant particularly suitable for the present invention, melamine cyanuric acid can be mentioned.

In the present invention, the blending ratio of the triazine flame retardant is 1 to 2 with respect to 100 parts by weight of the polyamide resin.
It is used in an amount of 5 parts by weight, preferably 2 to 20 parts by weight, more preferably 3 to 15 parts by weight. If the amount is less than 1 part by weight, the flame retardant effect is not observed. If the amount exceeds 25 parts by weight, the flame retardancy is effective, but gas is generated during molding to improve the appearance of the molded product. It is not preferable because it is damaged or mechanical properties are deteriorated.

In the present invention, the polyamide resin and the triazine-based flame retardant are preferably melt-kneaded, and a known method can be used for the melt-kneading. For example, using a Banbury mixer, a rubber roll machine, a kneader, a single-screw or twin-screw extruder, etc., the composition can be melt-kneaded at a temperature of 150 to 350 ° C.

As the method for compounding the polyamide oligomer in the present invention, any compounding method such as dry blending, surface adhesion, melt kneading, and master pelletization may be used.

The present invention is a reinforcing agent, an impact resistance improving agent, a heat stabilizer, a weathering agent, an inorganic crystal nucleating agent, a fatty acid metal, as long as it does not adversely affect the flame retardancy, fluidity, releasability and mechanical properties. You may add salt, a coloring agent, etc.

In the present invention, it is surprising to use an amide of a dibasic acid such as N, N'-bisstearylsuccinamide and a monoamine or an amide of a diamine and a monocarboxylic acid such as ethylenestearylamide in combination. It is possible. The inventors of the present invention have invented a fact that cannot be inferred from conventional knowledge. That is, when a conventional release agent such as ethylene bis-stearyl amide is blended, no improvement in physical properties is observed as described above, but with the polyamide oligomer of the present invention having a limited terminal and molecular weight. By using ethylenebisstearylamide in combination, the addition amount of the polyamide oligomer used in the present invention can be reduced without impairing the effects of the present invention.

The polyamide resin composition of the present invention is a resin composition having excellent mechanical properties while further improving flame retardancy, fluidity, and mold releasability, such as switches, ultra-small slide switches and DIP switches. , Switch housing,
Lamp sockets, cable ties, connectors, connector housings, connector shells, IC sockets, coil bobbins, bobbin covers, relays, relay boxes, capacitor cases, motor internal parts, small motor cases, gears, cams, dancing pulleys, spacers. ,
Insulators, casters, terminal blocks, power tool housings, starter insulating parts, canisters, chamber tanks, fuse boxes, air cleaner cases, air conditioner fans, terminal housings, intake and exhaust pipes, bearing retainers, cylinder head covers, intake manifolds, water Pipe / impeller, clutch release bearing hub, heat-resistant container, microwave oven component, rice cooker component, printer / ribbon guide, and other electrical / electronic-related components, automobile / vehicle-related components, household / office-related electrical product components, computer-related components,
It is useful for facsimile / copier-related parts, machine-related parts, and other various applications.

[0032]

EXAMPLES The usefulness of the present invention is described in detail below with reference to examples, but the present invention is not limited thereto. The flame retardancy shown in this example was determined according to the UL-94 method, and the mechanical properties were determined according to the ASTM method. For the fluidity (spiral flow) shown in this example, an injection molding machine was used to mold a 1 mm thick flow length test piece at a resin pressure of 1000 kg / cm 2, and the spiral flow length of the test piece was measured. The mold releasability was evaluated by using an injection molding machine, molding a box-shaped molded product at a resin pressure of minimum filling pressure +50 kg / cm 2, and measuring the pressure of the ejecting pin at that time. If the pressure of the ejector pin is low, it indicates that the releasability is good. In addition,
Melt kneading temperature and injection molding temperature in case of nylon 6,
Molding was carried out at a cylinder temperature of 245 ° C., a mold temperature of 80 ° C., and in the case of nylon 6.6, a cylinder temperature of 275 ° C. and a mold temperature of 80 ° C.

Reference Example A raw material shown in Table 1 was charged into an autoclave having a pressure resistance of 30 kg / cm 2 and the temperature was raised to 180 ° C. in a nitrogen atmosphere under a sealed pressure. After reaching 180 ° C., pressure was released while maintaining the temperature inside the tube, and the pressure inside the tube was brought to atmospheric pressure over 3 hours. After this, the reaction was continued under a nitrogen stream for 1 hour while gradually raising the temperature.

After cooling, the contents were pulverized to obtain a polyamide oligomer of AF.

The molecular weight of the polyamide oligomer was calculated by GPC analysis using α-chloronaphthalene or hexafluoroisopropanol as a solvent.

Aliphatic amide compounds of Comparative Examples G and H were also prepared in the same manner.

[0037]

[Table 1] Examples 1 to 7 Nylon 6 having a relative viscosity of 2.5, nylon 6.6 having a relative viscosity of 2.7, melamine cyanuric acid, melamine and polyamide oligomers (A to F) were added to a ribbon blender in the proportions shown in Table 2. After charging and mixing, a 40 mmφ vented extruder was used to melt-knead and pelletize. Next, the pellets obtained were used for Sumitomo Nestal injection molding machine Promat 4
0/25 (manufactured by Sumitomo Heavy Industries, Ltd.) was used to mold combustion test pieces, tensile test pieces, spiral flow, and box-shaped molded products.

As a result, it was found that the flame-retardant polyamide resin composition of the present invention was excellent in flame retardancy, fluidity, mold releasability and mechanical properties and had a good molding appearance.

Comparative Examples 1 to 2 Melamine cyanuric acid and polyamide oligomers (GH) were charged in the same nylon as in Examples in the proportions shown in Table 2, and test pieces were obtained in the same manner as in Examples. The same evaluation was performed.

The surface appearance and flame retardancy were good, but the fluidity, releasability and mechanical properties were not sufficient.

Comparative Example 3 Nylon similar to that used in Example was mixed with melamine cyanuric acid.
The test pieces were prepared in the same manner as in the examples, and the same evaluation was performed.

The surface appearance and flame retardancy were good, but the fluidity, releasability and mechanical properties were not sufficient.

Comparative Example 4 Evaluation was carried out in the same manner as in Example. However, due to the large amount of polyamide oligomer compounded, the flowability and releasability were good, but the flame retardancy and rigidity were reduced, and the surface appearance was also It was bad.

Comparative Example 5 Evaluation was carried out in the same manner as in Example. However, since the blending amount of melamine cyanuric acid was large, the flame retardancy was good, but the fluidity and rigidity were lowered, and the surface appearance was also poor. ..

Comparative Example 6 Polyamide oligomer was added to nylon similar to that used in Example 2.
The test pieces were prepared in the same manner as in the examples, and the same evaluation was performed.

The surface appearance, fluidity and releasability were good, but the flame retardancy and mechanical properties were not sufficient.

[0047]

[Table 2]

[0048]

EFFECTS OF THE INVENTION The flame-retardant polyamide composition of the present invention has good fluidity and releasability, can shorten the molding cycle, can remarkably improve the productivity, and can obtain the molded article obtained. It is possible to obtain a product having a good appearance, flame retardance, and mechanical properties.

Claims (1)

[Claims] 1. A polyamide oligomer 0.001 having a molecular weight of 5000 or less and having (B) a hydrocarbon group having 5 to 30 carbon atoms at the end, based on 100 parts by weight of the polyamide resin (A).
-10 parts by weight and (C) triazine flame retardant 1-25
A flame-retardant polyamide resin composition containing parts by weight.