KR101010001B1 - Thermoplastic elastomer and a gasket for a drum type washing machine produced thereby - Google Patents

Abstract

The present invention is a polyfunctional acrylate monomer having a molecular weight of 150 ~ 2,000g / mol; A propylene-ethylene random copolymer having a melt flow index of 5 to 50 g / 10 min and an ethylene content of 1 to 7%; And thermoplastic elastomers made from oil-added ethylene-propylene-non-conjugated diene terpolymers having a mooney viscosity of 40-60 ML (1 + 4) / 125 ° C. and Shore A (Shore) A) It relates to a drum washing machine gasket of 30 to 60 people.

Thermoplastic Elastomers, Gaskets, Injection Molding

Description

Thermoplastic elastomers and gaskets for drum washing machines manufactured therefrom {Thermoplastic elastomer and a gasket for a drum type washing machine produced}

The present invention relates to a thermoplastic elastomer and a gasket for a drum washing machine manufactured therefrom, and more particularly, to low hardness, high heat resistance, low odor, and injection molding using a multi-functional acrylate monomer. And, it relates to a thermoplastic elastomer and a gasket for a drum washing machine made therefrom.

Conventional drum washing gaskets were prepared by mixing ethylene-propylene-non-conjugated diene terpolymer (EPDM) and other additives with a conventional mixer, melting and injecting in a compression molding machine or rubber injection machine, and then vulcanizing molding ( Korean Patent Registration No. 10-0373146). Looking at the specific manufacturing method for this is the same as Scheme 1.

<Scheme 1>

Looking at Reaction Scheme 1, when the gasket is manufactured using sulfur as an initiator, it can be seen that the tight crosslinked structure, that is, the crosslinking density is high, so that the oil content is not large. Accordingly, in the process of generating the gasket, stickiness and mold contamination of the final product may occur due to oil bleed-out, and the elasticity decreases and the hardness increases due to the deepening of the oil leakage caused by repeated use of the washing machine. May cause problems. In addition, the conventional drum washing machine gasket manufacturing method according to Scheme 1 has a long vulcanization time (3 ~ 5 minutes), low productivity, and has a disadvantage of a lot of smell due to sulfur compounds generated during the cross-linking process using sulfur (sulfur). have.

In order to overcome such disadvantages due to odor, a technique for adding fragrance (Korean Patent Registration No. 10-0470765) has been proposed. However, when the fragrance is added, the sulfur compound odor is not eliminated, but is masked. Therefore, the fragrance and the sulfur compound odor are mixed, and the effect may be insignificant.

 Further, a technique (Japanese Patent Laid-Open No. 09-188787) capable of injection molding and having no odor has been proposed. However, in the above technique, thermal stability is low because EPDM and SEBS which are not crosslinked are used. Therefore, when applied to a drum washing machine having a drying and boiling function (operating temperature 95 ℃), there is a disadvantage that the phenomenon such as tearing may occur due to deterioration of the gasket. In addition, the low hardness resin of the related art has a low fluidity, there is a possibility that a problem due to the formation of flow-mark (weld-line), flow-mark (flow-mark), weld-line during the injection molding of the product.

As a resin to solve the above problems, a resin composition (registration number 10-0495177) in which a soft elastomer copolymer is blended with a polypropylene resin has been proposed. However, the proposed resin composition has a problem in that it is difficult to apply to a drum washing machine gasket having to absorb vibrations of the drum washing machine at high hardness (Shore A 80-90). In addition, even if the low hardness can be achieved by changing the composition, there may be a problem of decrease in elasticity and hardness increase due to oil leakage (oil bleed-out), and product quality may decrease due to non-uniformity during crosslinking.

SUMMARY OF THE INVENTION In order to solve the problems of the prior art as described above, an object of the present invention is to provide a thermoplastic elastomer and a drum washing machine gasket made from the same, which are excellent in injection moldability, low hardness, high heat resistance and no smell. In addition, an object of the present invention is to reduce the gasket forming time significantly, improve the productivity, recycling is possible (recycling) is environmentally friendly, low odor gasket for drum washing machine that can produce a high sensitivity product quality To provide.

The present invention relates to a gasket for a drum washing machine made of a thermoplastic elastomer. In the present invention, a gasket for a drum washing machine is installed between a drum and a door of a washing machine to prevent leakage and absorb vibration and noise of the drum. Means parts for sealing. The gasket may have high elastic restoring force to prevent leakage, and a large amount of oil may be contained so that there is no problem such as mold contamination during molding, deterioration of elasticity due to oil bleed-out, and hardness increase. In addition, even after repeated use of the drum washing or drying function of the washing machine should be equipped with high thermal durability so that problems such as deterioration, discoloration and tearing do not occur.

In order to achieve the above object, the present invention is a polyfunctional acrylate monomer having a molecular weight of 150 ~ 2,000g / mol; A propylene-ethylene random copolymer having a melt flow index of 5 to 50 g / 10 min and an ethylene content of 1 to 7%; And a thermoplastic elastomer made from oil-added ethylene-propylene-unconjugated diene terpolymer (oil-extended EPDM) with a Mooney viscosity of 40-60 ML (1 + 4) / 125 ° C. Provides gaskets for drum washing machines with Shore A 30-60.

In addition, the present invention (A) Mooney viscosity of 40 ~ 60ML (1 + 4) / 125 ℃ oil-added ethylene-propylene-non-conjugated diene terpolymer, process oil, melt flow (melt flow preparing a first mixture of a propylene-ethylene random copolymer having an index of 5 to 50 g / 10 min and an ethylene content of 1 to 7%; (B) adding a multifunctional acrylate monomer and an additive having a molecular weight of 150 ~ 2,000g / mol in the first mixture and mixing in a double screw extruder; And (C) a gasket for a drum washing machine having a hardness of Shore A 30 to 60, which is made of a thermoplastic elastomer prepared by injecting an initiator by side feeding in the double screw extruder to perform dynamic vulcanization. To provide.

In addition, the present invention is 0.5 to 20% by weight of a polyfunctional acrylate monomer having a molecular weight of 150 ~ 2,000g / mol; 3-30 wt% of a propylene-ethylene random copolymer having a melt flow index of 5-50 g / 10 min and an ethylene content of 1-7%; It provides a thermoplastic elastomer, characterized in that the Mooney viscosity is made from 50 to 90% by weight of an oil-added ethylene-propylene-unconjugated diene terpolymer having a mooney viscosity of 40 to 60 ML (1 + 4) / 125 ° C. do.

Drum washing machine gasket made of the thermoplastic elastomer of the present invention, it is possible to implement a low hardness due to the large amount of oil can be contained, very low oil bleed-out due to repeated use of the washing machine, such as elastic lowering and hardness increase The problem is low and the long-term thermal durability is high and there is no deterioration or tearing even after repeated use of the drum washing or drying function.

In addition, the gasket for a drum washing machine made of the thermoplastic elastomer of the present invention can manufacture a product with a general plastic injection molding machine, which can significantly shorten the molding time, thereby improving productivity. The gasket for a drum washing machine of the present invention is mounted on the front door portion of the drum washing machine and has a low hardness and high heat resistance suitable for preventing leakage and vibration absorption of a washing machine. In addition, the gasket for a drum washing machine of the present invention is environmentally friendly due to recycling (recycling), it can be applied to the production of high sensibility quality product with less smell.

EMBODIMENT OF THE INVENTION Hereinafter, this invention is demonstrated in detail.

The gasket for a drum washing machine of the present invention has a hardness of A 30 to 60, and the thermoplastic elastomer thereof is a polyfunctional acrylate monomer having a molecular weight of 150 to 2,000 g / mol; A propylene-ethylene random copolymer having a melt flow index of 5 to 50 g / 10 min and an ethylene content of 1 to 7%; And an oil-added ethylene-propylene-nonconjugated diene terpolymer (moon extended viscosity) having a Mooney viscosity of 40-60 ML (1 + 4) / 125 ° C.

When the hardness of the gasket for a drum washing machine of the present invention satisfies the above-described range, the physical properties and vibration absorption performance applicable to the drum washing machine gasket can be realized. When the hardness of the manufactured gasket is 30 or less, it is difficult to satisfy tear strength and creep resistance, and when it is 60 or more, it is difficult to implement vibration absorption performance that can be used as a gasket for a drum washing machine.

By applying the polyfunctional acrylate monomer having a molecular weight of 150 to 2,000 g / mol to the thermoplastic elastomer, low hardness and high heat resistance are imparted to the thermoplastic elastomer which is a raw material of the gasket for the drum washing machine of the present invention. Here, the high heat resistance is a functional group of the polyfunctional acrylate-based monomer reacts with the double bond of the non-conjugated diene of the ethylene-propylene-non-conjugated diene terpolymer with the addition of oil to realize a three-dimensional cross-linked structure Therefore, it can be said that it is obtained. Low hardness means that the polyfunctional acrylate monomer serves as a linkage between ethylene-α-propylene-diene, and at this time, the polyfunctional acrylate monomer having a molecular weight of 150 to 2,000 g / mol When applied, it increases the free volume between molecules and increases the oil content that can exist in this space, minimizing oil bleed-out and thus preventing stickiness of the final product. This makes it possible to effectively maintain the low hardness of the product. Low hardness products typically use oil to achieve low hardness. This oil bleed-out is closely related to mold contamination and product durability, which prevents end product productivity and low hardness. And durability to maintain durability.

In this case, the polyfunctional acrylate-based molecular weight is 150 ~ 2,000g / mol is effective for oil leakage control, less than 150g / mol of the space between the molecules is too small, the amount of oil can be reduced, the relatively high hardness When the molecular weight exceeds 2,000 g / mol, the crosslinking effect is lowered, resulting in a loss of heat resistance.

The polyfunctional acrylate monomer is included in the thermoplastic elastomer at 0.5 to 20% by weight. If the addition range and molecular weight mentioned above are satisfied, the thermoplastic elastomer which has low hardness and high heat resistance can be manufactured.

Examples of the multifunctional acrylate monomers include 1,6-hexanediol diacrylate, 1,6-cyclohexanediol diacrylate, 2,2 2,2-dimethyl-1,3-propanediol diacylate, diethylene glycol diacrylate, 1,3-butylene glycol dimethacrylate (1,3-butylene glycol dimethacrylate) and trimethylolpropane trimethacrylate. Dual diacrylate monomers are more effective at lower hardness and oil bleed-out delays than triacrylate monomers.

In more detail, when an organic peroxide that is an initiator is applied without using a polyfunctional acrylate monomer, crosslinking proceeds to a structure as shown in Scheme 2, and there is not much space between molecules, so that hardness is high and oil content is insufficient. Will result.

<Scheme 2>

However, when 1,6-hexanediol diacrylate is used as a diacrylate-based monomer among polyfunctional acrylate monomers, a space between relatively large molecules is secured as shown in Scheme 3, thereby increasing the amount of oil.

<Scheme 3>

Referring to Scheme 3, it can be seen that the thermoplastic elastomer has a loose crosslinked structure, that is, a low crosslinking density, and thus, the oil-containing amount is large. This loose crosslinked structure minimizes oil bleed-out in the thermoplastic elastomer, eliminating stickiness of the final product and effectively maintaining low hardness.

In addition, when using trimethylolpropane trimethacrylate as the triacrylate monomer among the multifunctional acrylate monomer, as shown in the following Scheme 4 it can be confirmed that to secure a space between the molecules less than when applying diacrylate have. However, oil content is higher than that of monomers such as divinylbenzene, which is generally applied, and is advantageous for low hardness due to flexible molecular structure.

<Scheme 4>

On the other hand, the polyfunctional acrylate monomer has a low molecular weight may be lost by evaporation, it can be used in combination with a porous material having a very large surface area, such as silica, diatomaceous earth, etc. to prevent it and to ensure uniform kneading.

The propylene-ethylene random copolymer having a melt flow index (MI) of 5 to 50 g / 10 min and an ethylene content of 1 to 7% has a major influence on the flowability of the thermoplastic elastomer as a final product. Crazy Therefore, the flow index should be at least 5g / 10min or more to ensure injection molding of the final product, and 5 ~ 50g / 10min to satisfy the final product properties.

The propylene-ethylene random copolymer having an ethylene content of 1 to 7% is preferably contained in the thermoplastic elastomer at 3 to 30% by weight. When the above range is satisfied, the physical properties of the final product are improved and the fluidity is excellent.

Propylene-ethylene random copolymer products having an ethylene content of 1-7% are advantageous for the low hardness of the final thermoplastic elastomer due to its flexibility. In addition, when the ethylene content exceeds 7% ethylene is activated by the initiator to participate in the crosslinking, it is difficult to implement excellent flowability, less than 1% is difficult to implement the low hardness of the product.

The oil-added ethylene-propylene-non-conjugated diene terpolymer having a Mooney viscosity of 40 to 60 ML (1 + 4) / 125 ° C. is a thermoplastic elastomer that is a raw material of the gasket for a drum washing machine of the present invention. Low hardness, excellent tear strength and excellent creep resistance can be realized. The diene is norbornene, it is preferable because it can implement high heat resistance. When the Mooney viscosity satisfies the above-mentioned range, it is possible to ensure uniform mixing with polypropylene having a fluidity index of 5 to 50 g / 10 min.

The oily ethylene-propylene-unconjugated diene terpolymer having a Mooney viscosity of 40-60 ML (1 + 4) / 125 ° C. is included in the thermoplastic elastomer of the present invention at 50-90% by weight. . When the above-mentioned range is satisfied, the thermoplastic elastomer, which is a raw material of the gasket for the drum washing machine of the present invention, can realize low hardness, excellent tear strength and excellent creep resistance, and if it is 50% or less, the vibration absorbing performance and elastic restoring force are insufficient. At 90% or more, injection molding is almost eliminated.

On the other hand, in addition to the oil added to the ethylene-propylene-non-conjugated diene terpolymer for low hardness expression, a separate process oil may be included.

The thermoplastic elastomer, which is a raw material of the gasket for the drum washing machine of the present invention, is prepared by including an initiator to advance the crosslinking reaction. The initiator applies a di-tertiary butyl peroxide or di-tertiary amyl peroxide system, which is an organic peroxide, for smooth odor removal of the final product. Since the organic peroxide is contained in a small amount in the thermoplastic elastomer, in order to maximize the effect of ease of addition and a small amount, it may be used in combination with a porous material having a very large surface area such as silica, diatomaceous earth, and the like. The organic peroxide is decomposed after the crosslinking reaction to produce acetone, tertiary butanol and tertiary amyl alcohol. Most of these decomposition products disappear after being left at room temperature for a few days, or can be easily removed only by drying at a temperature of about 90 ° C.

The thermoplastic elastomer of the present invention may further include an inorganic material, an antioxidant, a UV stabilizer, a colorant, etc. for appearance, physical properties, or process stability.

Hereinafter, the manufacturing method of the thermoplastic elastomer which is a raw material of the gasket for drum washing machines of this invention is demonstrated.

The method for preparing the thermoplastic elastomer is (A) Mooney viscosity of 40 ~ 60ML (1 + 4) / 125 ℃ and oil added ethylene-propylene-unconjugated diene terpolymer, process oil, fluidity index ( melt flow index) of 5 to 50 g / 10 min, and a first mixture of propylene-ethylene random copolymers having an ethylene content of 1 to 7%.

The reason why the step (A) is preferentially performed is to facilitate uniform mixing and handling of raw materials in the process. In more detail, the oil-added ethylene-propylene-unconjugated diene terpolymer is present in the form of a bale, and thus it is not easy to mix in a double screw extruder used in a post process without cutting or the like. . Therefore, kneader or similar equipment is used for mixing first. The propylene-ethylene random copolymer and the ethylene-propylene-nonconjugated diene terpolymer copolymer to which the oil is applied in the present invention have the advantage that uniform mixing is possible when the above-mentioned fluidity index and viscosity are satisfied.

Subsequently, the method for preparing the thermoplastic elastomer of the present invention includes (B) adding a multifunctional acrylate monomer and an additive having a molecular weight of 150 to 2,000 g / mol to the first mixture and mixing the same in a double screw extruder. The polyfunctional acrylate monomer is included in the step (B) because when added in the step (A) is concerned about raw material loss due to evaporation. Additives such as inorganic fillers, process stabilizers, colorants, UV stabilizers and the like may be mixed in step (A) or (B) depending on the ease of processing.

Subsequently, the method for preparing the thermoplastic elastomer of the present invention includes (C) injecting an initiator by side feeding in the double screw extruder to perform dynamic vulcanization. It provides a manufacturing method. In the step (C), since the organic peroxide is used as the initiator, the odor due to the generation of sulfur compounds due to the vulcanization crosslinking used in the existing product does not occur. In the dynamic crosslinking of step (C), the double bond of the diene of the ethylene-propylene-non-conjugated diene terpolymer copolymer to which oil is added and the functional group of the polyfunctional acrylate monomer are sufficiently mixed in the steps (A) and (B). After the reaction is initiated and crosslinked by adding an initiator such as the organic peroxide in step (C), uniform crosslinking can be realized.

The drum washing machine gasket made of the thermoplastic elastomer of the present invention can be manufactured by injection molding, and is mounted on the front door part of the drum washing machine to have a low hardness and high heat resistance suitable for preventing leakage and absorbing vibration of a washing machine. In addition, the drum washing machine gasket made of the thermoplastic elastomer of the present invention can significantly shorten the molding time, thereby improving the productivity. In addition, the drum washing machine gasket made of the thermoplastic elastomer of the present invention can be recycled (eco-friendly), it is environmentally friendly, it is possible to produce a product with high sensibility quality is less smell. In addition, the gasket for a drum washing machine made of the thermoplastic elastomer of the present invention can solve the problem of product stickiness due to oil leakage, elasticity decrease and hardness increase over time, and can solve the problem of deterioration due to non-uniform crosslinking.

Hereinafter, preferred embodiments of the present invention are provided to aid in understanding the present invention. However, the following specific examples are provided only for easier understanding of the present invention, and the contents of the present invention are not limited thereto.

Examples 1-6 and Comparative Examples 1-3: Preparation of Thermoplastic Elastomers

Oil-added ethylene-propylene-nonconjugated diene terpolymers or styrene-ethylene-butylene-styrene copolymers, process oils, and propylene-ethylene random copolymers in the composition ratios shown in Table 1 were mixed in a kneader to form a first mixture. A mixture was prepared. The multifunctional acrylate monomer and the additive were added to the first mixture and mixed in a double screw extruder, followed by dynamic crosslinking by inserting an organic peroxide through side-feeding, and pelletizing to prepare a thermoplastic elastomer.

[Unit: parts by weight] Example 1 Example 2 Example 3 Example 4 Example 5 Comparative Example 1 Comparative Example 2 Comparative Example 3 PP 10 10 8 8 6 10 6 Currently Available Product EPDM 65 65 67 67 69 65 Process oil 25 25 25 25 25 25 38 SEBS - - - - - - 36 additive 10 10 10 10 10 10 20 Diacrylate 1.5 - 3 - 3 - - Triacrylate - 1.5 - 3 - - - Organic peroxide 0.09 0.09 0.15 0.15 0.15 - -

PP: propylene-ethylene random copolymer (MI = 11, GS Caltex)

EPDM: Oil added ethylene-propylene-ethylidene-norbornene (ENB) copolymer (Money viscosity: 45ML (1 + 4) / 125 ° C, Kumho Polychem)

SEBS: Styrene-ethylene-butylene-styrene copolymer (styrene-ethylene-butylene-styrene copolymer, styrene content 20%, Mooney viscosity: 47ML (1 + 4) / 100 ℃, Kuraray)

Process oil: Mineral oil KL1100B (40 ℃ kinematic viscosity 200cSt, manufacturer: Seojin Chemical)

Additive: CaCO ₃ (average particle size: 2㎛)

Diacrylate: 1,6-cyclohexanediol diacrylate 98% (manufacturer: Aldrich)

Triacrylate: 98% of trimethyllopropane trimethacrylate (manufacturer: Aldrich)

Organic Peroxide: 98% Di-butyl butyl peroxide (Manufacturer: PERGAN)

Currently on the market: LG's drum washing machine gasket

Test Example: Evaluation of Properties of Gasket for Drum Washing Machine

After the thermoplastic elastomer prepared above was injected into a general plastic injection molding machine to form a gasket for a drum washing machine, the test piece was taken to meet the test standard, and various physical properties thereof were measured. Comparative Example 3 was used to collect a test piece in accordance with the test standards in the product currently on the market.

<Test method>

Shore A: KS M 6518

MI (Melt flow index): ASTM D 1238 (200 ℃, 5kgf)

Tear Strength: KS M 6518

Permanent Compression Shrinkage (90 ℃): KS M 6518

Tensile Creep: ASTM D 2990 (90 ℃, 24hrs, 100g)

Flexural fatigue resistance (crack growth observed during flexural resistance test up to 1 million times): KS M 6695 (90 ℃, 3mm thickness, perforation = 2mm)

Physical property (unit) Example 1 Example 2 Example 3 Example 4 Example 5 Comparative Example 1 Comparative Example 2 Comparative Example 3 A scale 43 48 40 42 38 43 47 43 MI (g / 10min) 3.5 2.0 2.3 1.8 2.0 5.0 0.05 N / A Tear strength (Kgf / ㎠) 22 23 25 26 25 17 24 22 Permanent compression rate () 35 40 31 33 27 62 32 52 Tensile Creep (%) 2.0 0.6 0.6 0.4 0.2 124 1.2 0.4 Flexural fatigue resistance
{Crack size (mm) / number} ○ ○ ○ ○ ○ XX Χ ○

○: no crack growth

XX: 80,000 cracks started, 250,000 cuts

Χ: 120,000 cracks started, 480,000 cuts

Referring to Table 2, the drum washing machine gaskets prepared in Examples 1 to 5 had low hardness compared to Comparative Example 3, which is a drum washing machine gasket currently on the market, and thus it may be determined that the shock absorbing performance is excellent. In addition, the melt flow index (MI) is much higher than that of Comparative Example 2, which is a conventional SEBS-based thermoplastic elastomer composition, and thus it may be determined that injection molding is excellent, and tear strength is equivalent to or superior to Comparative Example 3. As a result of measuring the permanent compression rate at the drum washing machine operating temperature of 90 ° C, the drum washing machine gaskets prepared in Examples 1 to 5 were found to exhibit much lower permanent compression rate than the gaskets on the market. It is judged to have. The gaskets for drum washing machines prepared in Examples 1 to 5 were also considered to have equivalent tensile creep performance, and thus, the degree of permanent deformation was determined to be equivalent to that of Comparative Example 3. Furthermore, the results of the high temperature bending fatigue resistance test, which is similar to the environment in which the drum washing machine gasket is actually exposed during the washing machine operation, showed that the drum washing machine gaskets prepared in Examples 1 to 5 were higher than those of Comparative Example 2, and the same level as that of Comparative Example 3. The long-term thermal durability is also excellent.

Claims (6)

Polyfunctional acrylate monomers having a molecular weight of 150 to 2,000 g / mol; A propylene-ethylene random copolymer having a melt flow index of 5 to 50 g / 10 min and an ethylene content of 1 to 7%; And It is made of thermoplastic elastomer made from oil-added ethylene-propylene-unconjugated diene terpolymer (oil-extended EPDM) with Mooney viscosity of 40 ~ 60ML (1 + 4) / 125 ℃. Shore A 30 to 60 gaskets for drum washing machines. The method according to claim 1, 0.5 to 20% by weight of a multifunctional acrylate monomer having a molecular weight of 150 to 2,000 g / mol; 3 to 30% by weight of the propylene-ethylene random copolymer having a melt flow index of 5-50 g / 10 min and an ethylene content of 1-7%; The Mooney viscosity is 40 ~ 60ML (1 + 4) / 125 ° C, a thermoplastic elastomer made of 50 ~ 90% by weight of ethylene-propylene-non-conjugated diene terpolymer copolymer with oil, the hardness is Shore A 30-60 drum washing machine gasket. The method according to claim 1, The polyfunctional acrylate monomer is 1, 6-hexanediol diacrylate (1, 6-hexanediol diacrylate), 1,6-cyclohexanediol diacrylate (1,6-cyclohexanediol diacrylate), 2,2-dimethyl -1,3-propanediol diacrylate (2,2-dimethyl-1,3-propanediol diacylate), diethylene glycol diacrylate, 1,3-butylene glycol dimethacrylate (1 , 3-butylene glycol dimethacrylate) and trimethylolpropane trimethacrylate (trimethylolpropane trimethacrylate), characterized in that one selected from the group consisting of, a thermoplastic elastomer, the hardness of the Shore A 30-60 drum washing machine. The method according to claim 1, The thermoplastic elastomer is made of a thermoplastic elastomer, characterized in that it comprises an initiator of di-tertiary butyl peroxide or di-tertiary amyl peroxide system, the hardness of the thermoplastic elastomer Gasket for drum washing machines with Shore A 30-60. The method according to claim 1, (A) Mooney viscosity of 40 ~ 60ML (1 + 4) / 125 ℃, oil-added ethylene-propylene-unconjugated diene terpolymer, process oil, melt flow index of 5 ~ Preparing a first mixture of 50 g / 10 min and a propylene-ethylene random copolymer having an ethylene content of 1 to 7%; (B) adding a multifunctional acrylate monomer and an additive having a molecular weight of 150 ~ 2,000g / mol in the first mixture and mixing in a double screw extruder; And (C) a gasket for a drum washing machine having a Shore A 30 to 60 made of a thermoplastic elastomer prepared by injecting an initiator by side feeding in the double screw extruder to perform dynamic vulcanization. 0.5 to 20% by weight of a polyfunctional acrylate monomer having a molecular weight of 150 to 2,000 g / mol; 3-30 wt% of a propylene-ethylene random copolymer having a melt flow index of 5-50 g / 10 min and an ethylene content of 1-7%; A thermoplastic elastomer, characterized in that the Mooney viscosity is made from 50 to 90% by weight of an oil-added ethylene-propylene-unconjugated diene terpolymer having a mooney viscosity of 40 to 60 ML (1 + 4) / 125 ° C.