JPH0768454B2 - Flame-retardant polyamide resin composition - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION <Industrial field of application> The present invention relates to a flame-retardant polyamide resin composition having excellent impact resistance, and more specifically, it contains both brominated polyphenylene ether and brominated polystyrene. However, the present invention relates to a flame-retardant polyamide resin composition having good impact resistance and flame retardancy.

<Prior Art> Polyamide generally has excellent mechanical properties such as high strength, rigidity and abrasion resistance, and also has good moldability and processability.
Since it has excellent characteristics such as self-extinguishing property, it is widely used as an engineering resin in various fields such as mechanical parts, electric / electronic parts and automobile parts. Further, by mixing various modified polyolefins with polyamide, various groups of resin compositions called so-called high-impact nylon, which have significantly improved impact resistance, have been developed and their applications are expanding. While these high-impact nylons have high impact resistance, it is customary that the self-extinguishing property inherent to polyamide is impaired and the flame retardancy deteriorates because it is blended with flammable polyolefins. In recent years, as the use of high-impact nylon has expanded to the field of electric and electronic parts, a material having both high impact resistance and flame retardancy is required. In order to meet such requirements, some attempts have been made to make flame-retardant high-impact nylon, and a method of adding decabromodiphenyl ether to high-impact nylon (for example, Japanese Examined Patent Publication No. 61-40261), A method of adding octabromodiphenyl ether to high-impact nylon (for example, JP-A-58-196255) and a method of adding brominated polystyrene or brominated polyphenylene ether to high-impact nylon (for example, JP-A-61-293257). ) Etc. have been proposed.

<Problems to be Solved by the Invention> However, among the above-mentioned conventional techniques, in a system in which a low molecular weight flame retardant such as decabromodiphenyl ether or octabromodiphenyl ether is added to high impact nylon, the flame retardant stains on the surface of the molded article. So-called "blooming"
Occurs, resulting in contamination of the molded product and deterioration of physical properties. In addition, the method of adding brominated polystyrene to high-impact nylon reduces the impact resistance due to the low affinity of brominated polystyrene and high-impact nylon, and also reduces the flame retardancy especially in thin-walled molded products. However, the method of adding brominated polyphenylene ether to high-impact nylon has a problem that the melt fluidity of the resin composition is lowered. Therefore, the present situation is that a truly useful flame-retardant polyamide resin composition which satisfies both impact resistance and flame retardancy at the same time and has good moldability and surface appearance of the molded product has not yet been obtained. Therefore, as a result of intensive investigations by the present inventors to obtain a polyamide-based material that satisfies all of the above required performances, both brominated polyphenylene ether and brominated polystyrene are used in combination at a specific ratio and added to high-impact nylon. Thus, the inventors have found that the above-mentioned various problems can be solved at once and a useful flame-retardant high-impact polyamide resin composition can be obtained, and the present invention has been accomplished.

<Means for Solving Problems> That is, the present invention provides (A) a polyamide resin of 30 to 75% by weight,
(B) Modified polyolefin having 10 to 40% by weight of at least one functional group selected from the group consisting of a carboxylic acid group, a metal carboxylate group, a carboxylic acid ester group, a carboxylic acid anhydride group and an imide group in the molecule, ( C) Brominated polyphenylene ether having a structure represented by formula (I) 5-40
% By weight, 5-40% by weight of brominated polystyrene having a structure represented by formula (D) (II) and (E) antimony trioxide, zinc oxide, lead oxide, ferrous oxide, ferric oxide, ferric oxide 1 to 15% by weight of at least one flame retardant auxiliary selected from tin and stannic oxide (however, the total of (A) to (E) is 100% by weight) The present invention provides a conductive polyamide resin composition.

(Here, n represents an integer of 2 to 400 and m represents an integer of 30 to 1500.) The polyamide as the component (A) used in the present invention is an amino acid, a lactam, or a diamine and a dicarboxylic acid as main constituent components. And polyamide. Specific examples of constituent components include ε-caprolactam, enantolactam, ω
-Lactams such as laurolactam, ε-aminocaproic acid, 11-aminoundecanoic acid, amino acids such as 12-aminododecanoic acid, tetramethylenediamine, hexamethylenediamine, undecamethylenediamine, dodecamethylenediamine, 2,2,4- / 2,4,4-Trimethylhexamethylenediamine, 5-methylnonamethylenediamine, m-xylylenediamine, p-xylylenediamine, 1,3-bisaminomethylcyclohexane, 1,4-bisaminomethylcyclohexane, bis -Diamines such as p-aminocyclohexylmethane, bis-p-aminocyclohexylpropane and isophoronediamine, adipic acid, suberic acid, azelaic acid, sebacic acid, dodecanenic acid, 1,4-
There are dicarboxylic acids such as cyclohexanedicarboxylic acid, 1,3-dichlorohexanedicarboxylic acid, terephthalic acid, isophthalic acid, naphthalenedicarboxylic acid and dimer acid.
These constituents are subjected to polymerization in the form of a single kind or a mixture of two or more kinds, and any of the polyamide homopolymers and copolymers thus obtained can be used in the present invention. Polyamides particularly useful in the present invention are polycaproamide (nylon 6), polyhexamethylene adipamide (nylon 66), polyhexamethylene sebacamide (nylon 610), polyundecane amide (nylon 11), polydodecane. Amides (nylon 12), and copolymers and mixtures of these polyamides. The polymerization degree of the polyamide used here is not particularly limited, and one having a relative viscosity of a 1% concentrated sulfuric acid solution at 25 ° C. within the range of 1.5 to 5.0 can be arbitrarily used.

The (B) modified polyolefin of the present invention means ethylene, propylene, butene-1, pentene-1, 4-methylpentene-1, isobutylene, 1,4-hexadiene, dicyclopentadiene, 2,5-norbornadiene, 5- A carboxylic acid group is added to a polyolefin obtained by radical polymerization of at least one olefin selected from ethylidene norbornene, 5-ethyl-2,5-norbornadiene, 5- (1'-propenyl) -2-norbornene, and styrene. Obtained by introducing a monomer component having at least one functional group selected from a carboxylic acid ester group, a metal carboxylate group, a carboxylic acid anhydride group, and an imide group (hereinafter referred to as a functional group-containing component). Is a modified polyolefin.

Examples of the functional group-containing component include acrylic acid, methacrylic acid, maleic acid, fumaric acid, itaconic acid, crotonic acid, methylmaleic acid, methylfumaric acid, mesaconic acid,
Citraconic acid, glutaconic acid and metal salts of these carboxylic acids, methyl hydrogen maleate, methyl hydrogen itacone, methyl acrylate, ethyl acrylate, butyl acrylate, 2-ethylhexyl acrylate, hydroxyethyl acrylate, methyl methacrylate , 2-ethylhexyl methacrylate, hydroxyethyl methacrylate, aminoethyl methacrylate, dimethyl maleate, dimethyl itaconic acid, maleic anhydride, itaconic anhydride, citraconic anhydride, endobicyclo- (2.2.
1) -5-heptene-2,3-dicarboxylic acid, endobicyclo- (2.2.1) -5-heptene-2,3-dicarboxylic acid anhydride, maleimide, N-ethylmaleimide,
Examples include N-butyl maleimide and N-phenyl maleimide.

The method of introducing these functional group-containing components is not particularly limited, and a method of mixing with the main component olefins for copolymerization, or a method of graft-introducing the polyolefin with a radical initiator can be used. The amount of the functional group-containing component introduced is 0.001 based on the total amount of the modified polyolefin.
It is suitably in the range of -40 mol%, preferably 0.01-35 mol%.

Specific examples of the modified polyolefin particularly useful in the present invention include ethylene / acrylic acid copolymers, ethylene / methacrylic acid copolymers, and some or all of the carboxylic acid moieties in these copolymers, sodium, lithium, and potassium. Salts with zinc and calcium, ethylene / methyl acrylate copolymer, ethylene / ethyl acrylate copolymer, ethylene / methyl methacrylate copolymer, ethylene / ethyl methacrylate copolymer, ethylene / acrylic acid Ethyl-g-maleic anhydride copolymer, ("g" represents a graft, the same applies hereinafter), ethylene / methyl methacrylate-g-maleic anhydride copolymer, ethylene / ethyl acrylate-g-maleimide copolymer Coalescence, ethylene /
Ethyl acrylate-g-N-phenylmaleimide copolymer and partially saponified products of these copolymers, ethylene / propylene-g-maleic anhydride copolymer, ethylene / butene-1-g-maleic anhydride copolymer , Ethylene / propylene / 1,4-hexadiene-g-maleic anhydride copolymer, ethylene / propylene / dicyclopentadiene-
g-maleic anhydride copolymer, ethylene / propylene /
2,5-norbornadiene-g-maleic anhydride copolymer, ethylene / propylene-g-N-phenylmaleimide copolymer, ethylene / butene-1-g-N-phenylmaleimide copolymer, styrene / maleic anhydride Copolymers and the like can be mentioned, and these modified polyolefins can be straight-chain polymers having no cross-linking points, or polymers having a partially cross-linked structure obtained by enjoying a partial cross-linking reaction in the modification process. Good. The modified polyolefins can be used alone or as a mixture.

In the resin composition of the present invention, the mixing ratio of the component (A) polyamide resin and the component (B) modified polyolefin is (A).
/ (B) = 85/15 to 50/50 weight ratio is preferable, and 80/20 to 60/40 weight ratio is more preferable. If the amount of the modified polyolefin compounded is less than the above range, the impact resistance will be insufficient, and if it is more than the above range, the flame retardancy as well as the strength and rigidity will decrease, which is not preferable.

In the present invention, it is extremely important to use both the brominated polyphenylene ether as the component (C) and the brominated polystyrene as the component (D) as a flame retardant. Because, by using both of them together, a useful flame-retardant polyamide resin composition which can satisfy all of high impact resistance, flame retardancy and good fluidity can be obtained. For example, when only brominated polyphenylene ether is used as a flame retardant, the fluidity of the resin decreases and it is difficult to mold thin molded products, while when only brominated polystyrene is used, impact resistance is reduced. However, there is a problem such as a significant decrease in the value, and it is not possible to satisfy all the required characteristics. The blending amount of brominated polyphenylene ether and brominated polystyrene is 5 to 40% by weight, preferably 7 to 35% by weight, and the total amount of both is preferably 10 to 50% by weight, and 15 to 45% by weight. More preferably. The blending ratio of the brominated polyphenylene ether and the brominated polystyrene is not particularly limited, but as a blending ratio in which the actions of both are properly balanced, the brominated polyphenylene ether / brominated polystyrene =
It is preferably in the range of 90/10 to 10/90 weight ratio, and more preferably in the range of 70/30 to 30/70 weight ratio.

The flame retardant aid used as component (E) in the present invention is antimony trioxide, zinc oxide, lead oxide, ferrous oxide, ferric oxide.
Selected from iron, stannous oxide and stannic oxide,
These can be used alone or in the form of a mixture of two or more kinds. The amount of the flame retardant auxiliary compounded is 1 to 15% by weight, preferably 3 to 10% by weight. 1% by weight of flame retardant aid
If it does not meet the requirements, the flame retardance will be insufficient, which is not preferable.
If it exceeds 15% by weight, impact resistance is deteriorated, which is not preferable.

The method for producing the resin composition of the present invention is not particularly limited,
A mixture of polyamide resin, modified polyolefin, brominated polyphenylene ether, brominated polystyrene, and flame retardant auxiliary is a single or twin screw extruder, Banbury mixer,
A kneader, a method of melt-kneading at a temperature of 200 to 350 ° C. using a commonly known melt-kneader such as a mixing roll, and the like can be given as an example. Particularly, a method of melt-kneading using an extruder is simple and efficient. Yes preferred. The order of melt-kneading is not particularly limited, and a mixture of the above-specified five components may be kneaded together in a batch, and the polyamide and the modified polyolefin may be melt-kneaded in advance and then the flame retardant and the flame retardant auxiliary may be further kneaded, or the polyamide may be previously kneaded. It is also possible to employ a method in which the modified polyolefin is kneaded after kneading the flame retardant and the flame retardant auxiliary.

<Examples> The present invention will be described in more detail with reference to the following examples. The properties described in Examples and Comparative Examples were evaluated by the following methods.

(1) Melt index: JIS K7210 (2) Tensile property: ASTM D638 (3) Bending property: ASTM D790 (4) Izod impact strength: ASTM D256 (5) Combustibility: Length 5 inches, width 1/2 inch, Thickness 1 /
Formed 8, 1/16, 1/32 inch specimens, US UNDER WRI
It was measured according to the UL-94 standard defined by TERS LAB-ORATORIES.

(6) Melt viscosity: Measured using a melt indexer (L203 type) manufactured by Takara Kogyo Co., Ltd. under the conditions of 280 ° C. and a shear rate of 10 sec ⁻¹ .

Example 1 42 parts by weight of nylon 6 having a relative viscosity of 2.70, an ethylene / methacrylic acid / zinc methacrylate copolymer (an ionomer resin “HIMILAN” 170 manufactured by Mitsui DuPont Polychemical Co., Ltd.)
6) 23 parts by weight, 16 parts by weight of brominated polyphenylene ether (PO-64P manufactured by Great Lakes), 16 parts by weight of brominated polystyrene (68PB manufactured by Fellow) and 3 parts by weight of antimony trioxide were dry blended with a Henschel mixer. Then, using a 30mmφ twin-screw extruder, cylinder temperature 28
The mixture was melt-kneaded and pelletized under the conditions of 0 ° C. and screw rotation speed of 200 ppm. The pellets obtained here were vacuum dried at 100 ° C for 24 hours, then the cylinder temperature was 280 and the mold temperature was 80 ° C.
When injection molding was carried out under the above conditions, the flowability and moldability were good, and various test pieces were obtained without any trouble. The surface appearance of these molded products was extremely good without bleeding out. The properties and melt viscosities of the test pieces are summarized in Table 1.

It has been found that the resin composition obtained here is a material having excellent fluidity and surface appearance of a molded article, and having high impact resistance and flame retardancy, which is of extremely high practical value.

Comparative Example 1 Kneading and molding were carried out in exactly the same manner as in Example 1 except that brominated polyphenylene ether was not used and the blended amount of brominated polystyrene was 32 parts by weight. However, the Izod impact strength of the molded product obtained here is 21 kgcm / cmnotch,
The impact resistance was insufficient.

Comparative Example 2 An attempt was made to perform kneading in exactly the same manner as in Example 1 except that brominated polystyrene was not used and the blended amount of brominated polyphenylene ether was 32 parts by weight. However, the melt viscosity of the composition obtained here is extremely high at 84,000 poise, and the thickness is 1 /
A thin molded product such as 32 inches was not filled and the fluidity was insufficient.

Example 2 Kneading and molding were carried out in the same manner as in Example 1 except that the blending amounts of brominated polystyrene and brominated polyphenylene ether were changed to 8 and 24 parts by weight, respectively, to obtain various test pieces having a good surface appearance. These properties are as shown in Table 1, and it was found that these are also useful materials having excellent moldability, impact resistance and flame retardancy.

Example 3 Kneading and molding were carried out in the same manner as in Example 1 except that the blended amounts of brominated polystyrene and brominated polyphenylene ether were changed to 24 and 8 parts by weight, respectively, to obtain various test pieces having a good surface appearance. These had the properties shown in Table 1, and were also highly practical materials having good fluidity, impact resistance, and flame retardancy.

Example 4 52 parts by weight of nylon 66 having a relative viscosity of 2.90, 13 parts by weight of a modified polyolefin obtained by graft-adding 1% maleic anhydride to an ethylene / 1-butene copolymer having a melt index of 1 g / 10 min, and bromine. 14 parts by weight of polyphenylene ether, 14 parts by weight of brominated polystyrene, and 7 parts by weight of ferrous oxide were dry blended with a V blender, and then kneaded and molded in the same procedure as in Example 1 to obtain various molded products with good appearance. Got a piece. These various properties are as shown in Table 1, and it was found that the resin composition obtained here is also a high impact flame-retardant nylon with good fluidity.

Example 5 70 parts by weight of nylon 6 having a relative viscosity of 3.40, 30 parts by weight of an ethylene / propylene copolymer having a melt index of 3.0 g / 10 min, 0.8 part by weight of maleic anhydride and 0.7 of acrylamide.
A high impact nylon composition was prepared by melt-blending parts by weight of the mixture at 275 ° C. in the presence of a small amount of organic peroxide using a 65 mmφ single screw extruder.

A mixture of 68 parts by weight of the high impact nylon, 19 parts by weight of brominated polyphenylene ether, 9 parts by weight of brominated polystyrene and 4 parts by weight of antimony trioxide was kneaded at a cylinder temperature of 280 ° C. using a 30 mmφ twin-screw extruder. Molding was performed in the same procedure as in Example 1 to obtain various test pieces with good appearance. As shown in Table 1, this material was also found to be a material of high practical value having good fluidity and impact resistance and flame retardancy.

<Effects of the Invention> A feature of the present invention is that brominated polyphenylene ether and brominated polystyrene are used together as flame retardants in flame-retarding high impact nylon composed of polyamide / toughening material. Only by using both of them, liquidity,
Thus, it has become possible to obtain a useful high impact flame retardant polyamide resin composition which can satisfy all of the moldability, impact resistance and flame retardancy.

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Claims (1)

[Claims] 1. (A) Polyamide resin 30 to 75% by weight,
(B) Modified polyolefin having 10 to 40% by weight of at least one functional group selected from the group consisting of a carboxylic acid group, a metal carboxylate group, a carboxylic acid ester group, a carboxylic acid anhydride group and an imide group in the molecule, ( C) Brominated polyphenylene ether having a structure represented by formula (I) 5-40
% By weight, 5-40% by weight of brominated polystyrene having a structure represented by formula (D) (II) and (E) antimony trioxide, zinc oxide, lead oxide, ferrous oxide, ferric oxide, ferric oxide 1 to 15% by weight of at least one flame retardant auxiliary selected from tin and stannic oxide (however, the total of (A) to (E) is 100% by weight) -Resistant polyamide resin composition. (Here, n represents an integer of 2 to 400 and m represents an integer of 30 to 1500.)