JPS62275157A - Thermoplastic resin composition - Google Patents

Abstract

PURPOSE:To provide the title compsn. which has excellent moldability and gives molded products excellent in flexibility, resistance to impact and chemicals and the uniformity and smoothness of the appearance, by blending a polyamide resin with a specified ethylene copolymer having acid anhydride groups. CONSTITUTION:50-90wt% ethylene (a) is copolymerized with 5-49wt% alkyl ester of a 3-8C alpha,beta-unsaturated carboxylic acid (b) [e.g., an alkyl (meth) acrylate] and 0.5-10wt% maleic anhdride (c) to obtain an ethylene copolymer (B) having a melt index of 0.1-200g/10min. 5-59wt% at least one polyamide resin (A) selected from the group consisting of polyamide 6, polyamide 66, polyamide 12, etc., is blended with 95-41wt% component B.

Description

[Detailed Description of the Invention] 3. Detailed Description of the Invention [Field of Industrial Application] The present invention has a wide temperature range (has characteristics of being flexible and strong, and is useful for noise reduction gears, sports nose soles, This invention relates to a novel thermoplastic resin composition that is made of polyamide resin and ethylene copolymer and is used in products such as tubes, hoses, etc., and is highly flexible.

More specifically, the present invention relates to a novel thermoplastic resin composition with excellent physical property balance and excellent flexibility in appearance, which is made by blending a polyamide resin and an ethylene copolymer containing an acid anhydride group.

[Conventional technology]

Traditionally, soft vinyl chloride resin has been used as a material for producing hard rubber-like or leather-like molded products.

Ethylene-vinegar e! Vinyl cooking fat, thermoplastic urethane resin,
Nylon 10 or the like is commonly used. However, soft vinyl chloride resin has cold resistance, ethylene-vinyl acetate resin has wear resistance, thermoplastic urethane resin has moldability, and nylon 12 has cold resistance. is an obstacle to the development of practical applications.

Further, as described in Japanese Patent Publication No. 56-22468, a polyamide elastomer having appropriate rigidity and flexibility can be obtained by blending a polyamide resin and an ionic ethylene copolymer. However, although polyamide elastomers have relatively improved cold resistance, especially impact resistance at low temperatures, in addition to the heat resistance and abrasion resistance that polyamide resins inherently have, they are still insufficient. Due to its high rigidity, it has poor rubber elasticity and is therefore undesirable.

[Problem that the invention seeks to solve]

The purpose of the present invention is to solve these problems by applying an ethylene copolymer consisting of specific components, and to improve the heat resistance, abrasion resistance, and chemical resistance that are characteristic of polyamide elastomers. The object of the present invention is to provide a thermoplastic resin composition that has excellent cold resistance, particularly impact resistance at low temperatures, and a good balance between rubber elasticity and rigidity.

[Means for resolving intermission points]

From this perspective, the present inventors have conducted extensive and detailed research into ethylene copolymers that are effective when blended with polyamide resins, and have found that ethylene copolymers consisting of specific components have particularly high heat resistance and abrasion resistance. The present invention has been achieved by discovering that the material has excellent chemical resistance, cold resistance, especially impact resistance at low temperatures, and a good balance between rubber elasticity and rigidity.

In other words, one aspect of the present invention is.

(g) 5 to 59 parts by weight of polyamide resin;

fB) (a) Z Chileno 50-90% by weight, (1))
The present invention relates to a thermoplastic resin composition comprising 95 to 41 parts by weight of an ethylene copolymer having 49 types of α,β-unsaturated unsaturated carboxylic acid alkyl esters.

The component (a) polyamide resin in the present invention includes 3
Various polyamides obtained by polycondensation of lactams having more than one ring member, polymerizable ω-amino acids, dibasic acids, diamino, etc. can be used.

Specifically, ε-caprolactam, aminocaproic acid,
Ena/Tractum. Polymers such as 7-aminohbutanoic acid, 11-aminounobanoic acid, ω-laurolactam, and 12-aminododecanoic acid.

For example, polyamide 6, polyamide 11, polyamide 12
etc.

Alternatively, hexamethylene diamine, zonamethylene/noamine, and decamethylene diamine.

Diamines such as dodecamethylene diamine and metaquine diamine, terephthalic acid, isophthalic acid, anopic acid,
Polymers 1 obtained by polycondensation with dicarboxylic acids such as sepacic acid, dodecane dibasic acid, and geltaric acid, such as polyamides 6 and 6.

Examples include fatty polyamide resins such as polyamide 6, 10, polyamide 6 and 12, aromatic polyamide resins such as polyhexamethylene diamine terephthalamide, polyhexamethylene isophthalamide, and quinleno group-containing polyamide.

Furthermore, polyamide C 6, 6.6, which is a copolymer of ε-caprolactam, hexamethylenenoamino, adipinoic acid, and 11-aminounobucanic acid is also available. 1).

ε-caprolactam, hexamethylenediamine/.

Adipic acid, 12-aminododecanoic acid, or W-
Polyamide C 6, 6 copolymerized with laurolactam
．． 6, 12).

Among the above polyamides, this polyamide 6 is particularly suitable.

Polyamide 6, 6, Polyamide+2, Polyamide [6, 6.6. 12] is preferred.

In the thermoplastic resin composition according to the present invention.

The polyamide resin as a constituent component is at least one selected from the above-mentioned polyamide resins, and is contained in an amount of 5 to 59 parts by weight, preferably 10 to 55 parts by weight. If the polyamide resin component is less than 5 parts by weight, heat resistance and abrasion resistance will not be sufficient, and if it exceeds 59 parts by weight, cold resistance will be poor. In particular, favorable results cannot be obtained in terms of impact resistance and flexibility at low temperatures.

One of the (II + component component (B)) ethylene copolymers of the resin composition according to the present invention has a monomer component of (
a) ethylene, (b) α,β-unsaturated carboxylic acid alkyl ester, and (c) maleic anhydride;
a) 50-90% by weight of ethylene, preferably 60-8%
(b) 5 to 49 weight %, preferably 7 to 45 weight % of a, β-unsaturated carboxylic acid alkyl ester and (c) 0.5 to 10 weight % of maleic anhydride, preferably 1 ~8% by weight.

(b) α,β-unsaturated carboxylic acid alkyl ester is
Unsaturated carboxylic acids having 3 to 8 carbon atoms 1 For example, alkyl esters of acrylic acid, methacrylic acid, etc. Specific examples include ethyl acrylate, n-propyl acrylate, isopropyl acrylate, n-acrylate Gutil,
t-butyl acrylate, isobutyl acrylate, methyl methacrylate, ethyl methacrylate, n-methacrylate
propyl, isopropyl methacrylate, methacrylic acid n
-butyl, isobutyl methacrylate, etc. Among these, methyl acrylate, ethyl acrylate,
n-Butyl acrylate 1 Methyl methacrylate is preferred.

In addition, other copolymerizable monomer components 1, such as vinyl acetate, may be used within a range that maintains performance.

Also included are ethylene copolymers obtained by copolymerizing vinyl propionoate and the like.

In the ethylene copolymer used in the present invention (leaking component (B)), if (a) ethylene is less than 50% by weight, the composition with polyamide resin will have poor cold resistance.

In particular, favorable results cannot be obtained in terms of impact resistance at low temperatures and moldability. Moreover, when it exceeds 95% by weight, the compatibility with the polyamide resin decreases, which adversely affects the impact resistance and appearance of the molded product. Also, (b)4. When β-unsaturated carboxylic acid alkyl ester is less than 5% by weight or more than 49% by weight, cold resistance, especially impact resistance at low temperatures◆
No favorable results are obtained here. In addition, if (c) maleic anhydride is less than 0.5% by weight or more than 10% by weight, cold resistance, especially impact resistance at low temperatures, will decrease, and ◆
This also has a negative effect on molding processability and the appearance of the molded product.

Melt index (JI) of the ethylene copolymer (B)
SK6760) is 0.1 to 20 (1/lo minute,
Preferably it is in the range of 0.5 to 100P/10 minutes. If the melt index is less than 0.11/10 minutes, the molding processability and the uniformity of the appearance of the molded product will deteriorate.

If the heating time exceeds 200 f/710 minutes, the mechanical properties will deteriorate, which is not preferable.

In addition to the above ingredients, the resin composition of the present invention may further contain reinforcing agents such as glass fiber, calcium carbonate, clay, limestone, and carbon black, or fillers, and ethylene carbonate.

) Polypylene carb fragments, polypylene carbs.

It is possible to add modifiers such as butylene oxide, glycerin, stearic acid monoglyceride, polyethylene glycol, or plasticizers, and also add other additives such as heat stabilizers, ultraviolet absorbers, dyes, pigments, etc. In some cases, it may be preferable to use it as a composite composition.

There are no particular limitations on the method for producing the resin composition of the present invention.1
Commonly known methods can be used. From an industrial standpoint, a method of kneading in a molten state is actually preferable.

Melt kneading can be carried out using commonly used kneading equipment such as BANOVA mixers, extruders, rolls, and various kneaders. It is preferable to uniformly mix the powder or pellets in advance in a device such as a tanobler or a he//el mixer, but if necessary (mixing may be omitted and each material is fed in a fixed amount to a kneading device separately). A method can also be used.

The kneaded resin composition is injection molded or extruded.

Although molding can be performed by various other molding methods, the present invention also provides a method of obtaining a molded product by directly kneading during injection molding or extrusion molding (such as tri-blending and kneading directly during melt processing operation) without going through a kneading process in advance. includes.

〔Example〕

The present invention will be explained below with reference to Examples, but the present invention is not limited thereto.

In addition, the bending elastic modulus in the examples is JIS K? 203(
The thickness was 2 m). Tensile strength at break and elongation were measured according to JIS K 6301 (2 thicknesses). Izotsu impact strength is JIS K7
110 (thickness 4+Ill+, measurement temperature -40°C1
■-Notched). Vicat softening point was performed according to ASTM D 1525. Permanent elongation is J
Performed according to IS K6301. Meret index is JIS K6760 (190°C, 216
0? ) is the measurement result.

In the present Examples and Comparative Examples, the following were used as component V () polyamide resin and component (9-functional ethylene copolymer cup or polyethylene).

(9) Made of polyamide resin Ube Industries ■, UBE nylon ■1 (l l l B
(Polyamide 6) Manufactured by Ube Industries, Ltd., UBE Nylon ■2020B (Polyamide 6.6) Manufactured by Nippon Rirsa Co., Ltd., Bratamide ■Hu05 (Polyamide (6,6,6,121 copolymer) (B) Ethylene copolymer or Polyethylene Among the ethylene copolymers described below, Bondine ■ is patented in French Patent No. 113233.
No. 79 and French Patent Application No. 81101430.

Made by CED Nifu, Bondine X8040 (E/EA/MAR=72.8/26/1.2% by weight.

Ml: 9r/10 minutes) Made by Sumika NDF ■, Bodyne ■ X8030 (E/EA/MAR=87.5/10/2.5% by weight.

Ml: 4.4 r/10 minutes) Bondine ■X8060 manufactured by Sumiichi HISDF■ (E/EA/MAR=69.8/27.1/3.1% by weight.

Ml: 34 r/10 min) Acrift WA3036-04 manufactured by Sumitomo Chemical # (E/MMA=70/30% by weight, Ml: 5 r/1
0 minutes) Made of three pieces of polychemical ■, Imilano ■M600
4 (E/MAA, Zn-MA=91/9% by weight.

Ml: 10? /10 minutes) manufactured by Sumitomo Chemical, Sumikisen L-705 (MI near r/10 minutes, polyethylene), where E, ethylene,
EA ethyl acrylate, ~fAH: maleic anhydride, MMA: methyl methacrylate, MAA methacrylic acid.

Zn-tvlA Zinc methacrylate, MI:/ruto (indicates ndenox).

Examples 1 to 8 and Comparative Examples 1 to 3 Using a single screw extruder with a 30-tube vent, predetermined temperatures (260°C for polyamide 6, 280'C for polyamide 6.6, Example 5 and 6 are 260°C) and kneaded with the resin compositions shown in Tables 1 and 2 for various resin compositions.

After drying, use a 3.5 oz injection molding machine (manufactured by 8 Seijin Kogyo Co., Ltd.
Molding was carried out using FS75 (N) type), and the physical properties were
A regular test piece was obtained.

The measurement results were as shown in Tables 1 and 2.

From the results of Examples 1 to 8, the resin composition according to the present invention has excellent impact resistance at low temperatures, is rich in rubber elasticity with a high elastic recovery rate, and has a very good balance with rigidity. I understand that there is something.

On the other hand, the resin composition of Comparative Example 1 is unfavorable in terms of uniformity of appearance because it causes a phenomenon of phase separation in the molded article, and also has insufficient Fl resistance at low temperatures.

The resin composition of Comparative Example 2 has good heat resistance and uniform appearance of the molded product (although phase separation is observed inside the molded product), but has high rigidity and poor flexibility. Furthermore, impact resistance at low temperatures is also insufficient.

Similarly to Comparative Example 1, the resin composition of Comparative Example 3 also suffered from the phenomenon of phase separation, which is not preferable in terms of uniformity of appearance. Furthermore, it is found that the impact resistance at low temperatures is insufficient and the rubber elastic properties are poor, making it unsuitable as an elastomer.

〔Effect of the invention〕

As described above, it can be seen that the thermoplastic resin composition of the present invention exhibits remarkable effects in terms of good molding processability, good balance of physical properties of molded products, and good appearance.

The novel highly flexible resin composition provided by the present invention can be easily used for forming molded products and sheets by molding processing methods such as injection molding and extrusion molding. It is processed to produce products with an extremely good balance of physical properties such as flexibility, impact resistance, and chemical resistance, as well as excellent uniformity and smoothness in appearance.

Claims (3)

[Claims] (1) (A) 5 to 59 parts by weight of polyamide resin and (
B) (a) 50-90% by weight of ethylene, (b) α, β-
A thermoplastic resin composition comprising 95 to 41 parts by weight of an ethylene copolymer containing 5 to 49 weight % of an unsaturated carboxylic acid alkyl ester and (c) 0.5 to 10 weight % of maleic anhydride. (2) Component (A) is polyamide 6, polyamide 6.6,
The thermoplastic resin composition according to claim 1, which is at least one selected from polyamide 12 and polyamide 12. (3) Component (B) is (a) 60 to 85% by weight of ethylene
, (b) α,β-unsaturated carboxylic acid alkyl ester 7
The thermoplastic resin composition according to claim 1, which is an ethylene copolymer containing -45% by weight and (c) 1-8% by weight of maleic anhydride.