JPS63170460A - Resin composition - Google Patents

Abstract

PURPOSE:To obtain a resin composition improved in flow properties and deterioration proofness in the molding process and low-temperature impact resistance after the heat treatment, by incorporating an aromatic amine compound and copper compound in a blend of polyamide and modified polyolefin. CONSTITUTION:The objective resin composition can be obtained by incorporating 100pts.wt. of a blend comprising (A) 95-50wt.% of an aliphatic polyamide with a relative viscosity 2-5 produced by melt polymerization and copolyamide or polyamide blend consisting mainly of said aliphatic polyamide and (B) 5-50wt.% of a modified polyolefin having carboxylic acid, its metal salt, carboxylic ester, acid anhydride or epoxy group (e.g., ethylene/acrylic acid copolymer) with (C) 0.005-3 (pref. 0.01-1)pts.wt. of an aromatic amine (e.g., N,N'-di-beta-naphthyl-p-phenylenediamine) and (D) 0.005-1 (pref. 0.01-0.5)pt.wt. of a copper compound.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a polyamide resin composition with improved flow characteristics during molding, prevention of deterioration, and low-temperature impact resistance after heat treatment.

Recently, in order to improve the impact strength of polyamide resin when dry or at low temperatures, and to obtain a material that can withstand severe usage conditions, progress has been made in the development of molding materials made of mixtures of polyamide and various ring polyolefins. Ethylene, α,
Copolymers with β-unsaturated carboxylic acids (for example,
2-12546), so-called ethylene-based ionomer resins made by adding metal ions such as sodium, magnesium, and zinc to a copolymer of ethylene and an α,β-unsaturated carboxylic acid derivative (for example, US Pat. No. 384)
5163, Japanese Patent Publication No. 54-4743), and modified polyolefins grafted with acid anhydrides or epoxy compounds (for example, Japanese Patent Publication No. 55-44108, Japanese Patent Publication No. 57-22347, Japanese Patent Publication No. 57-966)
No. 1, JP-A-55-165952), and the like. The polarity and reactivity of these modified polyolefins change depending on the various functional groups introduced into them, and as a result, they exist as a fine dispersed phase in the polyamide matrix phase and play the role of absorbing impact energy. The reaction between the functional groups of the modified polyolefin and the polyamide increases the viscosity of the mixture, which often causes a problem of deterioration of fluidity during molding, particularly during injection molding. In addition, mixtures of polyamide and various modified polyolefins as mentioned above certainly exhibit excellent impact strength not only at temperatures above room temperature but also at low temperatures below 0°C.
It has become clear that the material has a serious drawback in that the low-temperature impact strength is significantly reduced when heat treated at ~150°C for about 50 to 500 hours. This shows that when a molded product made of a mixture of polyamide and modified polyolefin is used for a long time in a high-temperature atmosphere, its impact strength gradually decreases and it becomes extremely brittle at low temperatures. This is one of the problems that must be improved before it can be applied.

The present inventors conducted studies aimed at improving the fluidity during injection molding and the low-temperature impact strength after heat treatment of a composition made of polyamide and modified polyolefin.2
The present invention was achieved by discovering that the above object can be effectively achieved by adding more than one specific additive in combination, and at the same time, a deterioration prevention function can be imparted.

That is, the present invention provides a modified polyamide containing 95 to 50% by weight and (1) at least one functional group selected from a carboxylic acid group, a carboxylic acid metal base, a carboxylic acid ester group, an acid anhydride group, and an epoxy group. Polyolefin =
Mixture 100 consisting of 5-50 %! Q aromatic amine compound: 0.005-331ji 1 part and 0 copper compound: 0.005-l]! A resin composition in which part of U is added and blended is provided.

A feature of the present invention is that the combined addition of an aromatic amine compound and a copper compound is extremely effective in improving the fluidity during injection molding of a mixture consisting of polyamide and modified polyolefin, and in preventing a decrease in low-temperature impact strength after heat treatment. At the same time, it also exhibits the so-called deterioration prevention effect of suppressing the decline in tensile elongation at break and tensile strength. Aromatic amine compounds are essential for improving fluidity during injection molding and preventing decreases in low-temperature impact strength after heat treatment. Copper compounds alone have no effect, but surprisingly aromatic amine compounds and copper compounds One thing to know is that by combining the two, you can obtain an extremely excellent improvement effect with a small amount added. In other words, among the copper compounds, hindered phenol compounds, aromatic amine compounds, phosphorus compounds, etc. that have been conventionally known as heat-resistant agents and antioxidants, only the combination of aromatic amine compounds and copper compounds can be used with polyamides and modified It has become possible to obtain a polyamide resin composition that exhibits specific effects on polyolefin mixtures, such as improving fluidity during injection molding and suppressing the decrease in low-temperature impact strength after heat treatment, thereby providing a material that can withstand harsh usage conditions. Ta.

The polyamide used in the present invention is not particularly limited, but may be a normal aliphatic polyamide such as polycaproamide (nylon 6), polyhexamethylene adipamide (nylon 66), polyhexamethylene dodecamide (nylon 61), etc.
0), polyundecamethylene adipamide (nylon 1
16), polyhexamethylene dodecamide (nylon 61
2), polyundecaneamide (nylon 11), polydodecanamide (nylon 12), and copolyamides and mixed polyamides containing these as main constituents are suitable.

Copolymerized polyamides and mixed polyamides contain not only polyamides whose constituent components are all aliphatic components, but also aromatic components, such as hexyl methylene iso-7 talamide (6e) components,
Nylon 6/6I co-orthogonal body, nylon 6/6T copolymer, mixture of nylon 66 and nylon 61 containing a small amount of hexamethylene tele-7 talamide (6T) component, metaxylylene adipamide (lVIXD6) component, etc. , nylon 6
Also included are mixtures of nylon MXD6 and nylon MXD6. The polyamide used here is usually produced by melting
Further, there is no limit to the degree of electrical integration, and any polyamide having a relative viscosity within the range of 'LO to 5.0 can be selected.

Typical examples of modified polyolefins used in the present invention having at least one functional group selected from carboxylic acid groups, carboxylic acid metal bases, carboxylic ester groups, acid anhydride groups, and epoxy groups include ethylene/acrylic Acid copolymer, ethylene/methacrylic acid copolymer, ethylene/7malic acid copolymer, ethylene/methacrylic acid/
Zinc methacrylate copolymer, ethylene/acrylic acid/
Sodium methacrylate copolymer, ethylene/isobutyl acrylate/methacrylic acid/zinc methacrylate copolymer, ethylene/methyl methacrylate/methacrylic acid/magnesium methacrylate copolymer, ethylene/ethyl acrylate co-electrolyte, ethylene/vinyl acetate co-polymer, ethylene/glycidyl methacrylate co-polymer, ethylene/vinyl d-acid/glycidyl methacrylate co-polymer, ethylene-g-maleic anhydride copolymer (
g” represents graft (the same applies hereinafter), ethylene/pq
Pyrene-g-maleic anhydride copolymer, ethylene/propylene-g-acrylic acid copolymer, ethylene/l-butene-g-7 malic acid copolymer, ethylene/1-hexene-
g-itaconic acid copolymer, ethylene/propylene-g-
endobicyclo(2,2,l)-5-hebutene-2,
3-dicarboxylic anhydride copolymer, ethylene/propylene-g-glycidyl methacrylate copolymer, ethylene/
Propylene/1.4-hexashefg; Ilt water mashimaleic acid copolymer tyrene/propylene/dicyclopentadiene-g-7 malic acid copolymer, ethylene/propylene/norbornadiene-g-maleic acid copolymer and ethylene /ln acid vinyl-g-acrylic acid copolymer, etc., and it is also possible to use two or more of these modified polyolefins in combination. The above-mentioned modified polyolefin can be produced by known methods, for example, Japanese Patent Publication No. 39-6810, Japanese Patent Publication No. 46-27527, Japanese Patent Publication No. 50-263.
Publication No. 0, Special Publication No. 52-43677, Special Publication No. 1983
It can be produced according to the methods disclosed in Japanese Patent Publication No. 5716, Japanese Patent Publication No. 53-19037, Japanese Patent Publication No. 41173-1973, Japanese Patent Publication No. 9925-1987, and the like. As for the ethylene ionomer, various grades commercially available under the trade names of 6-Surlyn, 6-Hi-Milano, and 6-Coholene can be used.

The modified polyolefin used in the present invention usually has a melt index of 0.01 to 50, although there are no particular limitations on the electrical properties.
One within the range of f/10 m can be arbitrarily selected. In addition, in the present invention, it is also possible to mix other low-yield polyolefins with the above-mentioned modified polyolefin, and these polyolefins include polyethylene, ethylene/propylene copolymer, ethylene/butene-1# polymer, and ethylene/propylene/dimer. A cyclopentadiene copolymer, an ethylene/propylene 15-ethylidenenorbornene copolymer, an ethylene/propylene/1,4-hexadiene copolymer, and the like can be used.

The mixing ratio of (4) polyamide and (6) modified polyolefin is polyamide; 95-50%, preferably 90-6
0Wffi% and modified polyolefin: 5-50%,
Preferably, it needs to be within the range of 1O to 40% coul. If the amount of modified polyolefin used is less than 5% by weight, the effect of improving impact strength will be small; on the other hand, if the amount of modified polyolefin used exceeds 50% by weight, the strength and heat resistance of the mixture will decrease. This is not preferable because the characteristics of polyamide are not exhibited and the original purpose of the polyamide resin composition is not achieved.

Typical examples of the Ω aromatic amine compounds used in the present invention are 4,4'-bis(4-α,α'-2methylbenzyl)diphenylamine and N,N'-diβ-su7thi-p-7 Such as 22 diamine. The total amount of polyamide and modified polyolefin is t00nt.
! 0.005 to 3M parts, more than 0.005 to 3M parts
It is appropriate to add 01-1 electric cough part. When the amount of aromatic amine compound added is less than 0.005 parts,
The unique effects of improving fluidity during injection molding and preventing a decrease in low-temperature impact strength after heat treatment are not fully demonstrated, and on the other hand, if the amount of these compounds added exceeds 3 parts by weight, they may precipitate on the surface of the molded product and deteriorate the appearance. This is not desirable as it may cause damage or damage to the paper. In the present invention, compounds commonly called peroxide decomposers, such as distearylthiodipropionate, laurylstearylthiodiglopionate, and dilaurylthiodiprobionate, are used in combination with the aromatic amine compound. It is also possible to add. These compounds improve fluidity even when added in the absence of aromatic amine compounds, and reduce
Does not exhibit the effect of preventing a decrease in IL impact strength.

The Ω copper compounds used in the present invention include cuprous chloride, cupric chloride, cuprous bromide, cupric bromide, cuprous iodine, cupric sulfate, cupric nitrate, and copper phosphate. , cupric tn acid, cupric salicylate, cupric stearate, cupric benzoate, and complex compounds of the above-mentioned inorganic halosaponized steel with xylene diamine, 2-mercaptobenzimidazole, benzimidazole, etc. It will be done. The amount of the copper compound to be used is 0.005 to 1 part, more preferably 0.005 to 1 part per 10 parts of the total amount of polyamide and modified polyolefin. O1
~0.5 part by weight is suitable.

When the amount of copper compound added is extremely small, the effect of preventing polyamide deterioration is small; - If too much of the blade steel compound is used, copper metal will be liberated during molding, reducing the product value due to coloring. So I don't like it. In the present invention, it is also possible to add an alkali halide in combination with the Ω copper compound. Examples of the alkali logenide compounds include lithium chloride, lithium bromide, lithium iodide, potassium chloride, potassium bromide, potassium iodide, sodium bromide, and sodium iodide.

The method of mixing the polyamide, (2) modified polyolefin, (0 aromatic amine compound and (JJ# compound) is not limited to samurai, and a commonly known method can be adopted. Namely, pellets of polyamide, modified polyolefin, A method of homogeneously mixing powder, small pieces, etc. and g-machining using a high-speed stirrer, and then melt-kneading the mixture using a single-screw or multi-screw extruder with sufficient kneading capacity. A method in which polyamide and modified polyolefin are kneaded in an extruder, a method in which polyamide and modified polyolefin are first melt-kneaded in an extruder, and then an aromatic amine compound and a copper compound are added during molding to perform molding such as injection or extrusion; Any method can be used, such as a method in which polyamide, modified polyolefin, and additives are triblended during molding and molded by injection or extrusion.

The resin composition of the present invention may contain other ingredients, such as pigments, dyes, reinforcing agents, fillers, mold release agents, lubricants, crystal nucleating agents, ultraviolet absorbers, and plasticizers, as long as they do not impair its moldability and physical properties. , antistatic agents, other additives, etc. can be added.

In particular, it is important to add four commonly known excipients and crystal nucleating agents to improve moldability, such as lN', N'-
Ethylene bisstearylamide N.

It is possible to add and introduce N'-methylene bis stearylamide, calcium stearate, barium stearate, aluminum stearate, montan acid wax, talc, clay, kaolin, and the like. Addition of plasticizer is also an effective method for obtaining extremely flexible materials.
and t H N-butylbenzenesulfonamide, N-
Methylbenzenesulfonamide, N-ethyl-〇, p-
Compounds such as toluenesulfonamide, p-oxybenzoic acid-2-ethylhexyl ester, and hexylene glycol can be used. In addition, by adding and blending can fibrous or powder reinforcing agents and fillers such as glass 64m1 asbestos A fiber, carbon M fiber, wollastenite, Merck, calcium carbonate, and caliquiscar temenate, it has high rigidity and high impact strength. A composition can be obtained.

The composition of the present invention can be used for general injection molded products, hoses, tubes,
Film, monofilament, wire-covered J1 hollow molded product,
It is useful for various uses such as lamination.

The present invention will be explained in more detail with reference to Examples below.

The physical properties of the test pieces described in Examples and Comparative Examples were measured and evaluated according to the following method.

(1) Relative viscosity: JIS K6810 (2)
Melt index: ASTM D1238
(3) Tensile properties: ASTM D638 (4) Bending properties: ASTM D790 (5) Izot impact strength: ASTIVI 0256 (6) Fluidity of injection molding: The so-called spiral flow length was measured using a spiral mold.

Example 1 For 100 parts by weight of an ethylene/propylene coelectrolyte consisting of 70 mol% ethylene and 30 mol% propylene,
α dissolved in a small amount of acetone.

0.03 parts by weight of α'-bis-t-butylperoxy-p-diisopropylbenzene and 0.5 parts by weight of maleic anhydride
After adding the East JT part, the mixture was kneaded and pelletized at 230° C. using an extruder with a diameter of 40 mm. After crushing this pellet, unreacted maleic anhydride is extracted with acetone,
Next, the grafted anhydrous malemono finished product was quantified using an infrared absorption spectrum of the press film, and it was found that it contained 0.35% by weight of maleic anhydride.

Ethylene/propylea g-maleic anhydride coelectrolyte obtained here (melt index: L5): 30 blood i
t% is mixed with 1% of nylon 66 nia 0mff having a relative viscosity of 2.60 obtained by melt polymerizing equimolar hexamethine/diamine adipic acid salt, and 4,4'-bis(4- After adding 0.3 parts by weight of α, α'-dimethylbenzyl) diphenylamine and 0.03 parts by weight of 2-mercaptobenzimidazole complex of copper iodide, the mixture was melt-kneaded and pelletized using an extruder with a diameter of 65 ffφ. did.

Next, after vacuum drying the pellets, an injection molding machine was used to mold the pellets under the conditions of a cylinder temperature of 275°C and a mold temperature of 80°C.
A spiral flow test with a thickness of u was conducted, and it showed excellent fluidity with a flow length of 901 when the injection pressure was 750 kq/d. In addition, Izotsu impact test pieces prepared by injection molding under the same conditions were
After heat treatment for a period of time, Wi
When we measured the impact strength and compared the values before and after heat treatment, we found that
As shown in the table, there was almost no change in Izot impact strength, and it was found that excellent low-temperature impact strength was maintained even after heat treatment.

A tensile test piece molded at the same time as the Izotsu impact test piece was heat-degraded in air at 130°C and changes in tensile elongation at break were examined. It turned out that it held.

The strength and elastic modulus at 23° C. and absolute dryness were as follows.

Tensile yield stress: 510 #/d Bending yield stress: 710 kg/d Bending modulus:
17,600 / cd Example 2 Relative viscosity 2.7 obtained by melt polymerizing ε-caprolactam
No. 5 nylon 6-nia 5mff 1% and ionomer resin “Himin 2in” 1706 manufactured by Mitsui Polychemical Co., Ltd.
(Melt index: 0.7, ethylene/methacrylic acid/zinc methacrylate co-hybrid): 25*% mixture 100*4,4'-bis(4-α,α
'-dimethylbenzyl)diphenylamine: 0.151
℃ parts, copper iodide: 0.03 parts were added and mixed uniformly with a high-speed stirrer, then melt-kneaded with an extruder having a diameter of 65 ffφ and pelletized.

After vacuum-drying the pellets, a spiral flow test with a thickness of 3M was performed using an injection molding machine under the conditions of a cylinder temperature of 250°C and a mold temperature of 70°C, and the injection pressure was 700 kq/c4. flow length 861
It showed excellent liquidity. In addition, Izotsu impact test specimens prepared by injection molding under similar conditions were placed in air for 1 hour.
After heat treatment at 20°C for 200 hours, the rJ impact strength was measured in the temperature range of 23°C to -40°C and the values before and after the heat treatment were compared.As shown in Table 1, there was almost no change in the Izot impact strength. It was found that the material retained excellent low-temperature impact strength even after heat treatment.

Next, a tensile test piece molded at the same time as the Izotsu m impact test piece was heat-degraded in air at 130°C, and changes in tensile elongation at break were investigated. It was found that it retains its toughness. The strength and elastic modulus were as follows.

Tensile yield stress: 5,50 #/cd Bending yield stress: 710 kg/d Bending modulus: 19,00
0 ky/d Table 1

Claims (1)

[Claims] (A) Polyamide: 95 to 50% by weight and (B) Modified polyolefin having at least one functional group selected from carboxylic acid group, carboxylic acid metal base, carboxylic acid ester group, acid anhydride group, and epoxy group: 5 A resin composition in which (C) an aromatic amine compound: 0.005 to 3 parts by weight and (D) a copper compound: 0.005 to 1 part by weight are added to 100 parts by weight of a mixture consisting of ~50% by weight. .