JPS59140258A - Polyamide resin composition - Google Patents

Abstract

PURPOSE:To provide a resin compsn. which has excellent resistance to impact and heat, gives moldings having excellent appearance and is highly useful as an engineering plastic, by melt-mixing an acid-modified olefin copolymer with a polyamide resin having a heat distortion temp. not lower than a specified temp. CONSTITUTION:A polyamide resin compsn. is obtd. by melt-mixing 1-100pts.wt. acid-modified olefin copolymer such as ethylene/(meth)acrylic acid copolymer with 100pts.wt. polyamide having a heat distortion temp. of 80 deg.C or above (ASTM D-684, a load of 18.6kg/cm<2>). The compsn. has high thermal stability, exhibits excellent mechanical properties even in a high-temperature atmosphere, and has greatly improved impact resistance and relatively low water absorption so that this compsn. is excellent in characteristics as an engineering plastic.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a blend composition of a polyamide resin with a heat distortion temperature of 80° C. or higher and an acid-modified olefin copolymer, which particularly has good impact resistance, heat resistance, and excellent appearance of molded products. This invention relates to a resin composition that is highly practical as engineering plastics.

Obtained by polycondensation of dicarboxylic acid and diamine, polymerization of cyclic lactam, or copolymerization of salt of cyclic lactam, dicarboxylic acid, and diamine (heat distortion temperature 80°C or higher)
Polyamide resin has been put to practical use in various fields as engineering plastics due to its excellent physical properties and appearance, including heat resistance such as thermal shape stability, mechanical properties, moldability, dimensional stability, and abrasion resistance. ing.

However, its impact resistance is low (improvement is desired in order to further expand its uses in the future).

Many methods are known for improving the impact resistance of polyamide resins, and various additives have been blended with polyamide resins to improve impact resistance. However, many of these compositions have problems such as significant loss of the properties inherent to polyamide resins, precipitation of additives due to insufficient compatibility, and markedly poor appearance of molded products.

The present inventors have conducted intensive research and found that a composition in which an acid-modified olefin copolymer is blended with a polyamide resin having a heat distortion temperature of 80°C or higher does not impair the thermal shape stability, which is the inherent property of the polyamide resin, and has impact resistance. The inventors have discovered that it is possible to provide a highly practical molding material with excellent molded product appearance by greatly improving properties, and have arrived at the present invention.

That is, in the present invention, 1 to 1 part of acid-modified olefin copolymer is added to 100 parts by weight of polyamide resin having a heat distortion temperature of 80°C or higher.
1] This relates to a polyamide resin composition formed by melt-mixing 0 parts by weight.

The polyamide resin used in the present invention is a polyamide obtained by polycondensation of a dicarboxylic acid and a diamine, polymerization of a cyclic lactam, or copolymerization of a salt of a cyclic lactam, a dicarboxylic acid, and a diamine. AST
MD-684, load 18.6 x 2) is in the range of 80°C or higher, preferably 100°C or higher. This polyamide can be basically produced by a known polyamide production method, and currently commercially available polyamides can be used. A representative example is GRILAMID TR
-55 [Ms, Hemy (Switzerland)], TROGAM
ID (9T [Dynamite, Norpel (West Germany)], etc., and these polyamide resins have a heat distortion temperature of 80°C.
Nylon 6, nylon 66 within the range that does not impair the above conditions.
, nylon 610. One or more of nylon 12, nylon 11, etc. can be used as a blend.

In the present invention, regarding the acid-modified olefin copolymer added to improve the impact resistance of polyamide resin,
These contain at least 50 mol %, preferably 80 mol % of 1-olefins such as ethylene, propylene, butene-
1, isobutyne, pentene-1, hexene-1, thecene-1,4-methylbutene-1,4-methylpentene-L
4. It should contain 4-dimethylpentene-1, vinylcyclohexane, styrene, alpha-methylstyrene, styrene substituted with lower alkyl substituents or the like. It is also possible to use mixtures of the abovementioned olefins. Copolymers obtained from ethylene and butene-1 or propylene are preferred, and commercially available products such as Tafmer A4085, Tafmer A4090, Tafmer A20090, etc. (ethylene-butene-1 copolymers, Mitsui Petrochemical industry■ products) and Tafmar PO280, Tafmer PO480, Tafmer P068
0, Tafmer PO380 such as Tafmer PO380 (ethylene-propylene copolymer, Mitsui Petrochemical Industries ■ product)
can be mentioned.

The acid component is introduced by a known method such as direct copolymerization of an α,β-unsaturated carboxylic acid comonomer with the above-mentioned olefin or graft copolymerization with a polyolefin or polyolefin copolymer. Examples of acid components include acrylic acid,
Examples include methacrylic acid, ethacrylic acid, itaconic acid, maleic acid (anhydride), fumaric acid, and monoesters of the above carboxylic acids. Suitable examples include acrylic acid, methacrylic acid and (anhydrous) maleic acid. Maleic acid (anhydride) is particularly preferred.

Typical acid-modified olefin copolymers are illustrated below, but the invention is not limited thereto.

Ethylene-acrylic acid copolymer, ethylene-methacrylic acid copolymer, ethylene-itaconic acid copolymer, ethylene-methyl hydrogen maleate copolymer, ethylene-acrylic acid-methyl methacrylate copolymer, ethylene-methacrylic acid -Ethyl acrylate copolymer, ethylene-methacrylic acid-vinyl acetate copolymer, ethylene-acrylic acid-vinyl acetate copolymer, ethylene-acrylic acid-vinyl alcohol copolymer, ethylene-methyl vinyl ether acrylic acid copolymer , ethylene-propylene-acrylic acid copolymer, ethylene-styrene-acrylic acid copolymer, ethylene-methacrylic acid-acrylonitrile copolymer, ethylene-fumaric acid-methylpinyleth 4-thyl copolymer,
Ethylene-vinyl chloride-acrylic acid copolymer, ethylene-vinylidene chloride-acrylic acid copolymer, ethylene-vinyl fluoride-methacrylic acid copolymer, ethylene-chlorotrifluoroethylene-methacrylic acid copolymer, chlorinated ethylene -Methacrylic acid copolymer, ethylene-butene-
1-methacrylic acid copolymer, ethylene-butene-1-(
anhydrous) maleic acid copolymer, ethylene copolymer, 3
-Methylbutene-1-acrylic acid copolymer, 4-methylpentene-1-methacrylic acid copolymer, 4,4'-dimethylpentene-1-acrylic acid copolymer, propylene-
Undeca acrylic acid copolymer, globylene-α-methyl-styrene-maleic acid copolymer, propylene-butene-fumaric acid copolymer, ethylene-vinylcyclohexane-acrylic acid copolymer, chlorinated ethylene-acrylic acid copolymer Coalescence and analogues.

Suitable examples include ethylene-butene-1-(anhydrous) maleic acid copolymer and ethylene-propylene-(anhydrous) maleic acid copolymer.

It is important that such acid-modified olefin copolymers contain monomers having acidic groups in an amount of 0.01 to 20% by weight, preferably 0.05 to 10% by weight. .

The amount of the acid-modified olefin copolymer added to the polyamide resin is 1 to 100 parts by weight, preferably 3 to 50 parts by weight, particularly preferably 5 to 20 parts by weight, based on 100 parts by weight of the polyamide resin.
Jukeibu Shigekaneru. If the amount of the acid-modified olefin copolymer added is greater than the above range, the resulting molded product will become too flexible and have poor thermal properties, which will deviate from the original purpose.

Furthermore, if the amount is small, the effect of the present invention will be small and it will be difficult to achieve the present invention.

In addition to the above-mentioned components, the composition of the present invention may include inorganic fillers, graphite, glass fibers, metal fibers, carbon fibers, gypsum fibers, ceramic fibers, coupling agents, plasticizers, thermal stabilizers, weathering stabilizers,
A mold release agent, a lubricant, a coloring agent, an antistatic agent, a flame retardant such as an organic halogen compound, a flame retardant aid such as azithymon trioxide, a foaming agent, etc. may be added.

In addition to the excellent properties of polyamide resins as engineering plastics, the composition of the present invention has even better properties such as heat resistance and impact resistance, and can be used in various extrusion or injection molded products such as tubes, hoses, etc. It can be used for applications such as sheets, films, blow molded products, precision industrial parts, electric wire coating materials, and coating materials for optical fiber cores for transmission.

In the present invention, the composition of the invention can be prepared by various known methods. For example, the raw materials are mixed uniformly in advance using a mixer such as a tumbler or Henschel mixer, and then fed to a -screw or twin-screw extruder for melt-kneading.
There is a method of preparing it as pellets.

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

[Production of acid-modified olefin copolymer] (Reference example-1) Ethylene-butene-1 copolymer (Tafmer A4090,
100 parts by weight, 1,3-bis (manufactured by Mitsui Petrochemical Industries, Ltd.),
tert-butylperoxypropyl)benzene 0.5
A measured portion of Li and 1 part of heavy metal maleic anhydride were uniformly mixed. The mixture was then kneaded in an extruder set at 220° C. and pelletized to obtain an acid-modified olefin copolymer [A1]. When the graph 1 of maleic anhydride was measured using an infrared spectrum, it was confirmed that 075 parts by weight of maleic anhydride was grafted onto this product.

(Reference Example-2) In Example-1, the olefin copolymer was replaced with an ethylene-propylene copolymer (Tafmer PO48, Mitsui Petrochemicals Co., Ltd.).
mW'), maleic anhydride becomes 083
Weight part Grafted acid-modified olefin copolymer [B
] was obtained.

Examples 1 to 9, Comparative Examples 1 to 5 After premixing at the blending ratio shown in Table 1, 250°C
The mixture was kneaded and pelletized using a vented 40% extruder heated to . A test piece was made from this pellet using a 3-ounce injection molding machine, and was placed in an atmosphere of 100°C to evaluate general mechanical properties such as bending yield strength, bending modulus, and isot impact strength (notched), as well as thermal shape stability. The bending strength, bending elastic modulus, and heat distortion temperature of were measured based on ASTM D-684. In addition, the equilibrium water absorption rate in water at 23°C was measured.

The results are summarized in Table-1. The test piece obtained in Comparative Example 4 had poor compatibility and a phenomenon of interphase separation was observed, making it impossible to measure physical properties.

(*) Polyamide resin (, RILAMID TR-55: Heat distortion temperature (1B,
Blood 9/an2) 134℃ Ems, Chemie (Switzerland) TROGAMID ■T: Heat distortion temperature (18,"X7/c
mF ) 124°C Dynamite Norpel (West Germany) Nylon 6 (Eastern Nylon CM1011): Heat distortion temperature (18,'kg/cm') 57°C Ube Industries Nylon 66 (Eastern Nylon CM3001N): Heat distortion temperature (18゜Nylon 12 (GRILAMID L-25): Heat distortion temperature (1B, "kg/m2) 51°C Ems, Chemie (Switzerland) It is clear from the results shown in Table 1 As described above, the composition obtained according to the present invention has high thermal shape stability, exhibits excellent mechanical properties even in a high-temperature atmosphere, and has greatly improved impact resistance. It has been confirmed that the composition of the invention has a relatively low water absorption rate and has excellent properties as an engineering plastic.

On the other hand, comparative examples outside the scope of the present invention have various problems such as a drastic decrease in mechanical properties in a high-temperature atmosphere, poor compatibility, no improvement in impact strength, and low water absorption. Compared to the invention composition, the composition was significantly limited in practical use.

Agent: Patent Attorney Katsutoshi Takahashi

Claims (1)

[Claims] Heat distortion temperature 80℃ (ASTMD-6814, load 1s,
A polyamide resin composition prepared by melt-mixing 1 to 100 parts by weight of an acid-modified olefin copolymer with 100 parts by weight of a polyamide resin having a polyamide resin having a polyamide resin of 6 kli'/i or more.