JP2000119512A - Flame-retardant reinforced polyamide resin composition - Google Patents

Abstract

PROBLEM TO BE SOLVED: To obtain a flame-retardant polyamide resin composition, having an ultrahigh flame retardancy, hardly causing a drip in the UL burning test, and having strengthened high stiffness. SOLUTION: This flame-retardant reinforced polyamide resin composition comprises (a) a polyamide resin, (b) a compound having a triazine ring with >=400 deg.C weight-decreasing temperature and (c) an inorganic reinforcing agent and has a compounding ratio satisfying each equation of 1<=B/A<=2, 5<=C<=50, and A+B+C=100 [the percentages of components (a), (b) and (c) expressed in terms of weight are represented by A, B and C wt.% respectively].

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

TECHNICAL FIELD The present invention relates to a reinforced polyamide resin composition having excellent flame retardancy. In particular, the present invention
The present invention relates to a flame-retardant reinforced polyamide resin composition suitably used for components such as connectors, breakers, magnet switches, plugs, and outlets in the electric and electronic fields, and electrical components in the automotive field. In particular, the present invention relates to a high-rigidity reinforced flame-retardant polyamide resin composition having non-drip-type flame retardancy without using a halogen-based flame retardant and red phosphorus.

[0002]

2. Description of the Related Art Conventionally, polyamide resins have a high mechanical strength,
Because of its excellent heat resistance, automotive parts, machine parts,
Used in fields such as electric and electronic components. In particular, in recent years, the demand for flame retardancy has become increasingly higher in electric and electronic parts applications, and a higher degree of flame retardancy is required than the self-extinguishing property inherent in polyamide resins. For this reason, Underwriters Laboratory UL94V
Numerous studies have been made to enhance the level of flame retardancy conforming to the -0 standard, and these methods generally employ a method of adding a halogen-based flame retardant or a triazine-based flame retardant.

For example, addition of a chlorine-substituted polycyclic compound to a polyamide resin (JP-A-48-29846) and addition of a bromine-based flame retardant such as decabromodiphenyl ether (JP-A-47-7134). , Addition of brominated polystyrene (JP-A-51-47044,
175371), addition of brominated polyphenylene ether (Japanese Patent Application Laid-Open No. 54-116054), addition of a brominated cross-linked aromatic polymer (Japanese Patent Application Laid-Open No. 63-317552), brominated styrene-maleic anhydride polymer. Addition of coalescence (JP-A-3-168246) and the like are known.
In particular, a composition in which these halogen-based flame retardants are blended with a polyamide resin reinforced with glass fiber, etc., is used for electrical and electronic parts, especially for connectors mounted or connected to printed laminates due to its high flame retardancy and high rigidity. It has been frequently used for applications. However, there is a suspicion that halogen-based flame retardants will generate corrosive hydrogen halides during combustion and emit toxic substances. Due to these environmental issues, there is a movement to regulate the use of plastic products containing halogen-based flame retardants. There is. For this reason, halogen-free triazine-based flame retardants have attracted attention and have been studied a lot. For example, technology using melamine as a flame retardant (Japanese Patent Publication No. 47-1)
714), a technique using cyanuric acid (JP-A-5
0-105744) and a technique using melamine cyanurate (JP-A-53-31759) are well known. Although the non-reinforced polyamide resin composition containing no inorganic reinforcing material obtained by these techniques has a high flame retardant level conforming to UL94V-0 standard, it is reinforced with an inorganic reinforcing material such as glass fiber to increase rigidity. There was a problem that the enhanced composition did not conform to the UL94V-O standard. When a vertical burning test specified in UL94 is performed, the temperature of the test piece reaches the melting point near the melting point of the polyamide resin reinforced with glass fiber, etc. due to the flame contact of the burner, and the resin can flow. The test piece creates a new area in contact with the sag flame and generates combustibles, and the glass fiber exerts the so-called candle core effect, thereby accelerating the decomposition of resin and the generation of combustibles, and eventually burning. One specimen drip, and 3
This is because the absorbent cotton spread just below 0 cm is ignited. For reinforced polyamide resin, a technique of blending a red phosphorus flame retardant as a method of imparting the flame retardant characteristics conforming to UL94V-0 standard which does not cause this drip phenomenon (Japanese Patent Publication No. 52-3807)
No. 3) is known, but there is a danger of ignition when handling red phosphorus and generation of harmful phosphine during molding. Therefore, halogen and red phosphorus satisfying UL94V-0 with high rigidity are required. There is a strong desire for the emergence of a global environment-friendly flame-retardant reinforced polyamide resin that does not contain any.

[0004]

SUMMARY OF THE INVENTION An object of the present invention is to provide a reinforced flame-retardant polyamide resin composition having extremely high flame retardancy and having no drip during UL burning and having high rigidity.

[0005]

Means for Solving the Problems As a result of intensive studies, the present inventors have found that, in a system in which an inorganic reinforcing material, a compound having a triazine ring and a polyamide resin are combined, a specific compound having a triazine ring and a polyamide resin are combined. It has been found that the object can be achieved only when the compounding ratio with the resin is set to a specific ratio, and the present invention has been completed based on this finding.

That is, the present invention provides a flame-retardant reinforced polyamide resin composition comprising (a) a polyamide resin, (b) a compound having a triazine ring having a weight loss temperature of 400 ° C. or more, and (c) an inorganic reinforcing material. When the weight percentages of the components (a), (b) and (c) in the composition are A, B and C, respectively, 1 ≦ B / A ≦ 25 5 ≦ C ≦ 50 A + B + C = 100 A flame-retardant reinforced polyamide resin composition having a compounding ratio satisfying the following.

Hereinafter, the present invention will be described in detail. The polyamide resin composition of the present invention comprises a polyamide resin (a), a compound having a triazine ring (b), and an inorganic reinforcing material (c).
Consists of The polyamide resin (a) used in the present invention includes polyamide 6 resin, polyamide 46 resin, polyamide 66 resin, polyamide 610 resin, polyamide 6 resin.
12 resin, polyamide 11 resin, aliphatic polyamide resin such as polyamide 12 resin, terephthalic acid such as hexamethylene terephthalamide, tetramethylene isophthalamide, hexamethylene isophthalamide, metaxylylene adipamide, isophthalic acid, xylylenediamine, etc. Aromatic polyamide resins containing the above-mentioned aromatic components, copolymerized polyamide resins containing these as main components, and mixed polyamide resins. In particular, in terms of heat resistance and moldability, polyamide 6 resin, polyamide 66 resin, copolymer of polyamide 66 resin and polyamide 6 resin, copolymer of polyamide 66 resin and polyamide 6I (polyhexamethylene adipamide) resin. Polymers and mixed polyamide resins thereof are preferred. Further, the molecular weight of these polyamide resins may be any as long as it is within the range in which molding is possible, and in particular, JIS K68
Polyamide resins having a sulfuric acid relative viscosity of 2.0 to 3.5 as shown in No. 10 are particularly preferable because they have good molding fluidity and can maintain a high level of flame retardancy.

The compound (b) having a triazine ring used as a flame retardant in the present invention must have a weight reduction temperature of 400 ° C. or higher. For a compound having a weight loss temperature of less than 400 ° C., even if the compound is blended in a large amount with a polyamide resin composition reinforced with a reinforcing material such as glass fiber, the compound may have a UL.
Although the combustion time during combustion is reduced, the drip phenomenon cannot be avoided, and when used in combination with a reinforcing material such as glass fiber, the effect as a flame retardant is extremely low. The weight loss temperature referred to herein is a value measured by a method in accordance with JIS K7120. In a TG curve measured at a heating rate of 10 ° C./min in dry air, the weight loss temperature is 50% of the initial weight. It is the temperature when the weight% is reached. As the compound (b) having a triazine ring having a weight reduction temperature of 400 ° C. or more, any compound having a structure can be used. For example, methylene dimelamine, ethylene dimelamine, decamethylene dimelamine, 1,3-cyclohexyl Melamines such as reaction products of melamine such as dimelamine, 4,4'-diethylenedimelamine, diethylenetrimelamine, hexaethyleneheptamelamine, melamine phosphate, melamine polyphosphate, melamine sulfate, melamine borate, and acidic compounds; Compounds and acetoguanamine,
Monoguanamine compounds such as benzoguanamine, succinoguanamine, adipoguanamine, phthaloguanamine,
Diguanamine compounds such as isophthaloguanamine, and 1,3,6-tris (4,6-diamino-1,3,3,6-tris) obtained by the reaction of 1,3,6-tricyanohexane and dicyandiamide obtained by electrolytic trimerization of acrylonitrile.
Examples thereof include guanamine-based compounds such as 5-triazin-2-yl) hexane (abbreviated as triguanamine in the present invention) and addition salts of these guanamine derivatives with cyanuric acid. These melamine compounds and guanamine compounds can be used in combination of two or more.
These melamine compounds and guanamine compounds have a surprising effect of exhibiting a high degree of flame retardancy when used in combination with an inorganic reinforcing agent such as glass fiber. Methylene dimelamine, ethylene dimelamine, melamine phosphate, melamine polyphosphate, melamine sulfate, succinoguanamine, adipoguanamine are particularly highly flame-retardant when the compound is blended with polyamide 66 resin and its copolymer. It is particularly preferable because it produces an effect.

The method for producing these flame retardants is not particularly limited. For example, ethylenedimelamine can be obtained by a condensation reaction of melamine and formaldehyde. Melamine sulfate is obtained, for example, by suspending and heating 1 mol of melamine and 0.5 mol of sulfuric acid in water, and reacting the suspension with 0.5 mol of sulfuric acid. Succinoguanamine is synthesized, for example, by heating dicyandiamide and succinonitrile in a solvent in the presence of an alkali catalyst. Each compound is a white solid, and is usually washed and dried, and the obtained solid is pulverized and used. In terms of the mechanical strength and appearance of the molded product obtained by molding the composition of the present invention, it is preferable to use a powder obtained by pulverizing these flame retardants to a particle size of 100 μm or less, preferably 50 μm or less. These flame retardants do not necessarily have to be completely pure, and some unreacted substances may remain.

The inorganic reinforcing material (c) used in the present invention is glass fiber, carbon fiber, potassium titanate fiber, gypsum fiber, brass fiber, stainless fiber, steel fiber, ceramic fiber, boron whisker fiber, mica, talc, silica. , Calcium carbonate, kaolin, calcined kaolin, wollastonite, glass beads, glass flakes, titanium oxide, and other fibrous, granular, plate-like, or needle-like inorganic reinforcing materials. These reinforcing materials may be used in combination of two or more. Particularly, glass fiber, wollastonite, talc, calcined kaolin and mica are preferably used. In addition, long fiber type roving as glass fiber,
It can be used by selecting from short fiber type chopped strand, milled fiber and the like. It is preferable to use glass fibers that have been surface-treated for polyamide.

In the present invention, when the weight percentages of the components (a), (b) and (c) in the polyamide resin set composition are A, B and C, respectively, 1 ≦ B / A ≦ 25 ≦ C ≦ 50 A + B + C = 100 must be blended.
When the component ratio B / A of the polyamide resin (a) and the compound having a triazine ring (b) is less than 1, the flame retardant effect is insufficient and UL94V-0 cannot be satisfied, and when the component ratio B / A exceeds 2, kneading occurs. This causes problems such as generation of time-decomposed gas, adhesion of contaminants to a molding die during molding, mechanical properties to be remarkably reduced, and deterioration of the appearance of molded products. A particularly preferred range is 1 ≦ B / A ≦ 1.5.

The proportion of the inorganic reinforcing material (c) is 5 to 50% by weight, preferably 10 to 45% by weight. When the content is 5% by weight or less, no manifestation of mechanical strength and rigidity is observed, and when the content is 50% by weight or more, not only the molding processability during extrusion or injection molding is remarkably reduced, but also no quantitative physical property improvement effect is observed. . Further, in order to achieve the object of the present invention, an inorganic flame retardant may be further added within a range that does not adversely affect mechanical properties and moldability. Preferred flame retardant aids include magnesium oxide, magnesium hydroxide, zinc oxide, zinc sulfide, iron oxide, boron oxide, zinc borate, and the like. The addition of magnesium hydroxide to the composition of the present invention is a particularly preferred embodiment because the tracking resistance is further improved in addition to the flame retardancy.

The method for producing the reinforced flame-retardant polyamide resin composition of the present invention is not particularly limited.
The compound having a triazine ring and the inorganic filler are mixed with a conventional kneader such as a single-screw or twin-screw extruder or kneader.
For example, a method of melting and kneading at a temperature of 20 to 350 ° C can be used. The reinforced flame-retardant polyamide resin composition of the present invention includes other components such as a pigment and a coloring agent such as a dye and a general heat stabilizer of polyamide, as long as the object of the present invention is not impaired. Copper-based heat stabilizers (for example, a combination use of potassium iodide and potassium bromide with copper iodide, copper acetate, etc.), organic heat-resistant agents represented by hindered phenol-based oxidation deterioration inhibitors, weather resistance improvers, nuclei Agents, plasticizers, lubricants, additives such as antistatic agents, and other resin polymers can be added.

The composition of the present invention can be prepared by injection molding, extrusion molding,
By a known method such as blow molding, connectors, coil bobbins, breakers, magnet switches, holders,
Molded into various molded products for electric, electronic, and automotive applications such as plugs, switches, and lighting equipment.

[0015]

The present invention will be described in more detail with reference to the following Examples, but it should not be construed that the present invention is limited thereto. The measurement methods used in Examples and Comparative Examples are shown below. [Measurement method] (1) Flame retardancy; UL94 (Under Write, USA)
rs Laboratories Inc.). The thickness of the test piece was 1
/ 32 inch and injection molding machine (made by Toshiba Machine: IS50
It was obtained by molding using EP). (2) Relative viscosity of sulfuric acid The relative viscosity with 98% sulfuric acid was measured according to JIS K6810. (3) Weight loss temperature; in dry air by a method based on JIS K7120,
A TG curve was obtained at a rate of temperature rise of 10 ° C./min, and a temperature at which the weight loss was 50% by weight with respect to the initial weight was obtained. (4) Mechanical properties Using an injection molding machine (TOSHIBA MACHINE: IS50EP),
A bending test piece (thickness: 3 mm) of STM D790 was formed, and a bending test was performed by a method in accordance with ASTM D790 to determine bending strength and flexural modulus.

[0016]

Example 1 Ethylene dimelamine having a weight loss temperature of 575 ° C. (manufactured by Hakkor Chemical Co., Ltd .: SHIGENOX-0W)
P) Polyamide 66 having 40% by weight of sulfuric acid and a relative viscosity of 2.6
Twin screw extruder (Toshiba Machine Co., Ltd.) so that 30% by weight of a / 6 copolymer (copolymerization ratio of polyamide 66: 90% by weight, melting point: 245 ° C.) is 30% by weight and glass fiber (03JA416 manufactured by Asahi Fiberglass Co., Ltd.) is 30% by weight. Cylinder temperature 260 ° C, screw rotation speed 200 using TEM35)
Under a condition of rpm, the polyamide resin and ethylene dimelamine were top-fed, the glass fibers were side-fed and kneaded, taken out into strands, cooled, and granulated with a cutter to obtain pellets. Various characteristics of the obtained pellets were examined by the above-mentioned measuring methods. Table 1 shows the results.

[0017]

Example 2, Comparative Examples 1-2 Pellets were obtained in the same manner as in Example 1 except that the mixing ratio of the polyamide resin, ethylene dimelamine and glass fiber was changed as shown in Table 1, and various characteristics were examined. . Table 1 shows the results.

[0018]

Example 3 Succinoguanamine having a weight loss temperature of 457 ° C. instead of ethylene dimelamine (200-mesh pass ground product of a compound synthesized by heating dicyandiamide and succinonitrile in a solvent in the presence of an alkali catalyst) ) And polyamide 66 having a relative viscosity of sulfuric acid of 2.8, and the characteristics were examined in the same manner as in Example 1. Table 1 shows the results.

[0019]

Comparative Example 3 The same procedure as in Example 1 was conducted except that melamine cyanurate having a weight loss temperature of 391 ° C. (MCA-CO manufactured by Mitsubishi Chemical Corporation) was used in place of ethylene dimelamine, and various characteristics were examined. Table 1 shows the results.

[0020]

Example 4 Melamine sulfate having a weight loss temperature of 445 ° C. (Apinon-901 manufactured by Sanwa Chemical Co., Ltd.) and a polyamide 66 / 6I copolymer (polyamide 6) having a sulfuric acid relative viscosity of 2.4
6 was carried out in the same manner as in Example 1 except that the copolymerization ratio of 82 was 82% by weight and the melting point was 246 ° C., and the ratio of talc (CRS6002 manufactured by Tatsumori) was as shown in Table 1. Various characteristics were examined. Table 1 shows the results.

[0021]

[Table 1]

[0022]

EFFECT OF THE INVENTION The composition of the present invention is a molding material which does not drip when UL94 is burned, has extremely high flame retardancy and is excellent in mechanical properties, and is used for home electric parts, electronic parts, automobile parts and the like. Can be used.

Continued on front page F-term (reference) 4J002 CL011 CL031 CL051 DA017 DA077 DE137 DE187 DE237 DG057 DJ007 DJ017 DJ037 DJ047 DJ057 DK007 DL007 DM007 EU186 EV256 EW026 FA017 FA047 FA087 FD017 FD136 GQ00

Claims (6)

[Claims] 1. A flame-retardant reinforced polyamide resin composition comprising: (a) a polyamide resin; (b) a compound having a triazine ring having a weight loss temperature of 400 ° C. or higher; and (c) an inorganic reinforcing material. When the weight percentages of the components (a), (b) and (c) are A, B and C, respectively, 1 ≦ B / A ≦ 25 5 ≦ C ≦ 50 A + B + C = 100 A flame-retardant reinforced polyamide resin composition having a compounding ratio. 2. The flame-retardant polyamide resin composition according to claim 1, wherein (a) the relative viscosity of sulfuric acid of the polyamide resin is 2.0 to 3.5. 3. The polyamide resin (a) is selected from a polyamide 6 resin, a polyamide 66 resin, a copolymer of a polyamide 66 resin and a polyamide 6 resin, and a copolymer of a polyamide 66 resin and a polyamide 6I resin. 3. The flame-retardant polyamide resin composition according to claim 1, which is at least one kind of polyamide resin. 4. The method according to claim 1, wherein the compound (b) having a triazine ring is at least one melamine compound selected from methylene dimelamine, ethylene dimelamine, melamine phosphate, melamine polyphosphate, and melamine sulfate. The flame-retardant polyamide resin composition according to claim 1, 2, or 3. 5. The method according to claim 1, wherein (b) the compound having a triazine ring is at least one guanamine-based compound selected from succinoguanamine, adipoguanamine, and triguanamine. Or the flame-retardant polyamide resin composition according to 3. 6. The (c) inorganic reinforcing material is a glass fiber,
The flame-retardant polyamide resin composition according to any one of claims 1 to 5, wherein the composition is at least one kind of reinforcing material selected from wollastonite, talc, calcined kaolin, and mica.