KR100690977B1 - Composition of thermoplastic elastomer - Google Patents

Abstract

The present invention relates to a thermoplastic elastomer composition.

The present invention, a) 30 to 60% by weight polyester thermoplastic elastomer; b) 30 to 60 wt% of an ethylene acrylate copolymer; And c) it provides a thermoplastic elastomer composition comprising 10 to 30% by weight of an unsaturated carboxylic acid ethylene copolymer.

The present invention further includes d) 0.5 to 2 parts by weight of a) alumino siloxane based on 100 parts by weight of a) a polyester-based thermoplastic elastomer, b) an ethylene acrylate copolymer and c) an unsaturated carboxylic acid ethylene copolymer component. Provided is a thermoplastic elastomer composition.

The present invention also provides a product which is obtained by injection or extrusion molding with polycarbonate or polyethylene terephthalate using a thermoplastic elastomer composition.

The thermoplastic elastomer composition of the present invention has excellent affinity with engineering plastics such as polycarbonate or polyethylene terephthalate, and has excellent interfacial adhesion, so that the double injection is easy, and swelling by oleic acid is minimized, and thus oleic acid resistance is excellent. . In addition, when used in addition to the alumino siloxane in the present invention, it provides a thermoplastic elastomer composition that is excellent in wear resistance and less surface migration during long-term storage is improved the problem of surface contamination.

 Polyester-based thermoplastic elastomer, ethylene acrylate copolymer, unsaturated carboxylic acid ethylene copolymer, alumino siloxane, double injection, overmolding

Description

Composition of thermoplastic elastomer

The present invention relates to a thermoplastic elastomer composition. More specifically, the present invention relates to a thermoplastic elastomer composition having improved interfacial adhesion with engineering plastics and swelling resistance to oleic acid, and having low surface migration and excellent wear resistance.

As advanced portable electronic products have been diversified in design and variety, various methods have been used to enhance the appearance and feel of products in addition to the mechanical properties of the housing materials. In particular, in the manufacture of tools such as drills or drivers or handles such as toothbrushes, the injection molding of soft materials into hard housing materials has resulted in the development of a technology that exhibits a soft and soft feel while satisfying the mechanical properties as housing materials. It is becoming.

When designing a product by the above double injection molding method and using a conventional thermoplastic elastomer as a soft material during molding, the thermoplastic elastomer does not have adhesion to hard materials such as polypropylene, polycarbonate, polyethylene terephthalate, and the like and thus is easily peeled off. There was a problem such as happening.

On the other hand, when a polyester-based thermoplastic elastomer is used as a soft material, it has a slight adhesive strength with hard materials such as polycarbonate, ABS, and polyterephthalate, but has a low adhesive strength and a relatively high hardness compared to conventional thermoplastic elastomers, resulting in a soft feel. It was hard to give. In addition, since swelling is easily caused by fatty acids or fatty acid compounds used in cosmetics, there was a disadvantage that peeling, contamination, etc. due to cosmetics transferred from the user's hand when used for a long time.

In addition, products containing polystyrene-based elastomers and ethylene-based rubber as soft materials showed satisfactory performance in hardness and tactile parts, but swelling by oleic acid was very severe, and when applied to products, fatty acids or fatty acid compounds There was a disadvantage that swelling and post-peeling occur.

In addition, in case of products using polyurethane-based thermoplastic resin as a soft material, the adhesive property with the hard material is excellent, but it is difficult to mold and process the product, and due to its low weatherability, it causes problems such as discoloration in long-term use. There was a problem that swelling occurred.

On the other hand, by using a polyester-based thermoplastic elastomer, in order to improve the soft touch, including an ethylene copolymer, ethylene methyl acrylate, ethylene ethyl acrylate, ethylene butyl acrylate, etc. The composition is known. However, in this composition, the swelling is caused by the oleic acid similar to the fatty acid, which is a raw material of the cosmetics currently used, there was a disadvantage that the swelling due to the swelling occurs when oleic acid deposition.

In addition, in the composition where abrasion resistance is a problem commercially, a prescription for improving the addition of ultra high molecular weight siloxane is commercialized. The occurrence of a decrease in adhesion at the interface of the liver often occurred.

In order to solve the above problems, the present invention is excellent in affinity with engineering plastics such as polycarbonate or polyethylene terephthalate and excellent in interfacial adhesion, and easy to double injection with them, and swelling by oleic acid is minimized to prevent oleic acid It is an object to provide a thermoplastic elastomer composition having excellent properties.

Another object of the present invention is to provide a thermoplastic elastomer composition having excellent wear resistance and less surface migration during long-term storage, thereby improving the problem of surface contamination.

The present invention to achieve the above object,

a) 30 to 60% by weight of polyester-based thermoplastic elastomer;

b) 30 to 60 wt% of an ethylene acrylate copolymer; And

c) 10-30% by weight of unsaturated carboxylic acid ethylene copolymer;

It provides a thermoplastic elastomer composition comprising a.

The present invention also relates to a total of 100 parts by weight of a) a polyester-based thermoplastic elastomer, b) an ethylene acrylate copolymer and c) an unsaturated carboxylic acid ethylene copolymer component,

d) It provides a thermoplastic elastomer composition further comprises 0.5 to 2 parts by weight of alumino siloxane.

In addition, the thermoplastic elastomer composition may be used for double injection molding or double extrusion molding of a molded article made of polycarbonate or polyethylene terephthalate.
In addition, the present invention provides a molded article obtained by double injection molding or double extrusion molding using the thermoplastic elastomer composition in a molded article made of polycarbonate or polyethylene terephthalate.
The molded article may be a handle portion of a tool or toothbrush.

Hereinafter, the present invention will be described in detail.

A) Polyester thermoplastic elastomer

Polyester-based thermoplastic elastomers have polyester as a hard segment in a molecule and have a low glass transition temperature (Tg) as a soft segment. It is a block copolymer using polyether or polyester, and a transesterification reaction in which a mixture of 1,4-butanediol and polytetramethylene ether glycol (PTMG) is reacted with a catalyst at reaction conditions of 150 to 200 ° C and at a high temperature of about 250 ° C. It is produced by the polycondensation reaction by pressure reduction reaction.

In addition, the melting point of the polyester thermoplastic elastomer of the present invention is 140 ~ 230 ℃, the hardness of the product was used as a Shore Hardness Tester (Shore Hardness Tester) using a polyester thermoplastic elastomer having a Shore hardness in the range of 35D ~ 62D It is preferable to use 30 to 60 weight% in total resin weight part, and it is more preferable to use 40 to 50 weight%. When less than 30% by weight is used, the heat resistance required for home appliances is reduced, resulting in heat deformation and deterioration of the product quality in the long term. In addition, when used in excess of 60% by weight, the soft touch is reduced, there is a problem that the swelling by oleic acid increases.

B) Ethylene Acrylate Copolymer

The ethylene acrylate copolymer of the present invention is a copolymer of one or more acrylate monomers in ethylene, and examples of the acrylate monomers of the copolymer include methyl acrylate, ethyl acrylate, butyl acrylate and 2-hydroxy. Ethyl acrylate and the like.

The ethylene acrylate copolymer is preferably in the content of the acrylate component 10-30% by weight or less. If it is less than 10% by weight may cause a decrease in adhesion, if it exceeds 30% by weight may cause problems in heat resistance.

The ethylene acrylate copolymer uses a product which is compatible with the polyester thermoplastic elastomer.

As for the ethylene acrylate copolymer used for this invention, it is preferable to use 30 to 60 weight% with respect to the total resin weight%, and it is more preferable to use 40 to 55 weight%. In case of using less than 30% by weight, the decrease in adhesive strength of the product occurs during double injection or overmolding. When used in excess of 60% by weight, there is a problem in that the use temperature of the composition decreases and the swelling caused by oleic acid increases due to the decrease in heat resistance.

C) unsaturated carboxylic acid ethylene copolymer

An unsaturated carboxylic acid or a derivative thereof may be used as the unsaturated carboxylic acid component in the copolymerization component of the unsaturated carboxylic acid ethylene copolymer of the present invention.

As the unsaturated carboxylic acid, acrylic acid, methacrylic acid, maleic acid, itaconic acid, citraconic acid, himic acid, bicyclo (2,2,2) octa-5-ene-2,3-dicarboxylic acid 4-methylcyclohexa-4-ene-1,2-dicarboxylic acid, 1,2,3,4,5,8,9,10-octahydronaphthalene-2,3-dicarboxylic acid, Bicyclo (2,2,1) octa-7-ene-2,3,5,6-tetracarboxylic acid, 7-oxabicyclo (2,2,1) hepta-5-ene-2,3- Dicarboxylic acid etc. are mentioned, for example.

Derivatives of unsaturated carboxylic acids include acid anhydrides, esters, amides, imides and metal salts, and include maleic anhydride, itaconic anhydride, citraconic acid anhydride, maleic anhydride, monoethyl ester of maleic acid and monoethyl ester of fumaric acid. Itaconic acid monomethyl ester, fumaric acid monomethyl ester, dimethylaminoethyl methacrylate, dimethylaminopropylacrylamide, acrylamide, methacrylamide, maleic acid monoamide, maleic acid diamide, maleic acid-N-monoethylamide, maleic acid -N, N-diethylamide maleic acid-N-monobutylamide, maleic acid-N, N-dibutylamide, fumaric acid monoamide, fumaric acid diamide, fumaric acid-N-monoethylamide, fumaric acid-N, N-diethyl Amide, fumaric acid-N-monobutylamide, fumaric acid-N, N-dibutylamide, maleimide, N-butylmaleimide, N-phenylmaleimide, acrylic acid There may be mentioned cerium, methacrylic acid, sodium acrylate, potassium methacrylate, potassium and the like.

The unsaturated carboxylic acid content of the product should be 7-20% by weight. If it is less than 7% by weight, there is a problem in oleic acid resistance, if it exceeds 20% by weight may cause a problem in mold release during processing.

The unsaturated carboxylic acid ethylene copolymer is preferably used in 10 to 30% by weight, more preferably in 15 to 20% by weight of the total resin weight%. When less than 10% by weight of the total composition of the resin is introduced, the improvement of the swelling properties for the oleic acid is less, and when used in excess of 30% by weight, the adhesive strength during the double injection and the problem occurs during processing.

D) Aluminosiloxane Additives

In order to improve the wear resistance, it is possible to use alumino siloxane-based master batch, wherein the content is 0.5 to 2 parts by weight based on 100 parts by weight of the total resin. When the amount is less than 0.5 parts by weight, the wear resistance is also improved, and when used in excess of 2 parts by weight, there is a problem in deterioration of adhesive strength during long molding and long-term storage.

Such alumino siloxane-based products have less deterioration in adhesive strength when stored for a long period of time than conventional siloxane type products, and less surface change due to migration.

In addition, the thermoplastic elastomer composition of the present invention may be used by further adding an antioxidant, a heat stabilizer, a light stabilizer, a lubricant, an antistatic agent, an inorganic or organic filler, and the like, as necessary.

Each of the above components may be kneaded simultaneously after dry blending. The kneading is usually carried out at 180 ° C to 260 ° C using a banbury mixer, co-kneader, roll mill, single screw or twin screw extruder, brabender, or the like. May be carried out at a temperature of 190 ℃ ~ 240 ℃.

The present invention can provide a product that is double-injected or overmolded with engineering plastics such as polycarbonate or polyethylene terephthalate using the thermoplastic elastomer composition.

Hereinafter, the present invention will be described in more detail with reference to the following examples, but the scope of the present invention is not limited to the examples.

Example 1

50 wt% of LG Chemical's Keyflex BT 1055 (55D) was used as the polyester-based thermoplastic elastomer, and 35 wt% of Elvaloy AC 1224 from DuPont, an ethylene methyl acrylate copolymer (EMA), was used as the ethylene acrylate copolymer. In this case, the content of methyl acrylate (MA) in Elvaroi AC 1224 was 24% by weight. As the unsaturated carboxylic acid ethylene copolymer component, 15 wt% of Nucreal 0903 manufactured by DuPont, an ethylene methacrylic acid copolymer (EMAA), was used, and the content of methacrylic acid (MAA) in Nucreal 0903 was 7%. % By weight.

For the polycarbonate (PC) resin used as the base material, a dumbbell-type tensile test specimen was made by using an injection molding machine, and then the middle was cut and placed in an injection mold. Then, by injecting the double injection material obtained by kneading each component of the composition at 220 ℃ using a twin screw extruder, to prepare a specimen to form an adhesive portion in the middle of the tensile specimen. Tensile tests were performed on the finished specimens at a crosshead speed of 200 mm / min using the universal testing machine, and the bond strength was determined by measuring the breaking strength of the adhesive surface.

After the specimen for measuring the adhesive strength was left in oleic acid for 24 hours in an oven (40 ℃) was determined whether the peeling.

In addition, the heat resistance was evaluated by the presence of deformation after leaving the injection specimen in an oven at 100 ℃ for 12 hours.

Table 1 shows the composition ratios and measurement results of the components.

Example 2

Example 1 except that Keyflex BT 1055 was used at 45% by weight instead of 50%, Elvaroi AC 1224 was used at 45% by weight instead of 35%, and Nucre 0903 was used at 10% by weight instead of 15%. The same procedure was followed.

Table 1 shows the composition ratios and measurement results of the components.

Comparative Example 1

The same procedure as in Example 1 was repeated except that only 100 wt% of Keyflex BT 1055 was used. Table 1 shows the composition ratio and measurement results of each component.

Comparative Example 2

Keyflex BT 1055 was used in 50% by weight instead of 55% by weight, Elvaroi AC 1224 was used in 50% by weight instead of 35%, Nucreal 0903 was carried out in the same manner as in Example 1.

Table 1 shows the composition ratio and measurement results of each component.

Comparative Example 3

Example 1 except that Keyflex BT 1055 was used in 20% by weight instead of 55%, Elbaroi AC 1224 was used in 70% by weight instead of 35%, and Nucre 0903 was used in 10% by weight instead of 15% by weight. The same procedure was followed.

Table 1 shows the composition ratio and measurement results of each component.

Example 1 Example 2 Comparative Example 1 Comparative Example 2 Comparative Example 3 Polyester thermoplastic elastomer (wt%) 50 45 100 50 20 Ethylene Methylacrylate Copolymer (wt%) 35 45 - 50 70 Ethylene Methacrylic Acid Copolymer (wt%) 15 10 - - 10 Adhesive force (g / cm) 1500 1400 700 1500 1600 Heat resistance test normal normal normal normal transform Naoleic Acid Experiment normal normal Peeling Peeling Peeling

Example 3

55 wt% of LG Chemical's Keyflex BT 1040 (40D) was used as the polyester-based thermoplastic elastomer, and ethylene butyl acrylate copolymer (EBA) (Ebaroy AC 3427, manufactured by DuPont) was used as the ethylene acrylate copolymer. Weight% was used, wherein the content of butyl acrylate (BA) was 27% by weight. As the unsaturated carboxylic acid ethylene copolymer component, 15% by weight of ethylene acrylic acid copolymer (EAA) (Daima, Primaco 3004) was used, wherein the content of acrylic acid (AA) in the ethylene acrylic acid copolymer was 9.7% by weight. .

Other than that, the adhesive force, oleic acid resistance, etc. were measured similarly to Example 1.

The composition ratio and measurement results of each component are shown in Table 2.

Example 4

50 wt% was used instead of 55 wt% for Keyflex BT 1040, 40 wt% instead of 30 wt% of ethylene butylacrylate (EBA), 10 wt% instead of 15 wt% of ethylene acrylic acid copolymer (EAA) It carried out similarly to Example 3 except having used.

The composition ratio and measurement results of each component are shown in Table 2.

[Comparative Example 4]

40% by weight of ethylene butyl acrylate (EBA) was used instead of 30% by weight, and 20% by weight of KEP-020P, an ethylene propylene rubber (EPR) manufactured by Kumho Petrochemical Co., Ltd., was not used. It carried out similarly to Example 3 except having used.

The composition ratio and measurement results of each component are shown in Table 2.

[Comparative Example 5]

Ethylene butyl acrylate (EBA) was used 40% by weight instead of 30% by weight, BB0808 (melt index (MI) of low density polyethylene (LDPE) manufactured by LG Chemical Co., Ltd. was 0.8 without using ethylene copolymer (EAA)). The density was carried out in the same manner as in Example 3, except that 20 wt% of 0.921) was used.

The composition ratio and measurement results of each component are shown in Table 2.

Comparative Example 6

50 wt% of Keyflex BT 1040 was used instead of 55 wt%, and without using ethylene acrylic acid copolymer (EAA), BD0390 (melt index (MI) was 0.3) Was carried out in the same manner as in Example 3 except that 0.949) was used in 20 wt%.

The composition ratio and measurement results of each component are shown in Table 2.

Example 3 Example 4 Comparative Example 4 Comparative Example 5 Comparative Example 6 Polyester thermoplastic elastomer (wt%) 55 50 40 40 50 Ethylene Butylacrylate Copolymer (wt%) 30 40 40 40 30 Ethylene Acrylic Acid Copolymer (wt%) 15 10 - - - Low density polyethylene (% by weight) - - - 20 - High density polyethylene (% by weight) - - - - 20 Ethylene Propylene Rubber (wt%) - - 20 - - Adhesive force (g / cm) 1400 1450 1400 1200 1100 Naoleic Acid Experiment normal normal Peeling Peeling Peeling

Example 5

As the polyester thermoplastic elastomer, 50 wt% of LG Chemical's Keyflex BT 1040 was used, and as the ethylene acrylate copolymer, 35 wt% of ethylene butyl acrylate copolymer (EBA) (DuPont, Elvaroi AC3427) was used. In this case, the content of butyl acrylate (BA) was 27% by weight. As the unsaturated carboxylic acid ethylene copolymer component, 15% by weight of ethylene methacrylic acid copolymer (EMAA) (Dupont, Nucreal 0903) was used, and the content of methacrylic acid (MAA) in Nucreal 0903 was used. Was 7% by weight.

In order to improve the wear resistance of the composition, 5 parts by weight of an ethylene methyl acrylate (EMA) master batch containing 10% alumino siloxane (manufactured by Xylochem) was mixed with respect to 100 parts by weight of the total components of the composition to compound the composition. It was.

The resistance to migration was measured by injection molding the test specimen for physical properties using the composition and leaving the sample at room temperature for 20 days to see if siloxane migrated to the surface.

Abrasion was measured after 1,000 revolutions using a taper abrasion tester (Taber abrasion tester, Toyoseiki Co., Ltd.) after the production of disk specimens, was calculated by the equation (1).

% Wear = (initial weight-weight after measurement) / initial weight * 100

In addition, the adhesive force and oleic acid resistance (swelling resistance) were measured similarly to Example 1.

Table 3 shows the composition ratio and measurement results of each component.

Example 6

Example 5 except that the composition was mixed with 15 parts by weight of an ethylene methyl acrylate (EMA) master batch containing 10% alumino siloxane (manufactured by Silochem Co., Ltd.), based on 100 parts by weight of the components. It carried out similarly.

Table 3 shows the composition ratio and measurement results of each component.

No migration of the alumino siloxane component was observed, whereby an improvement in the wear resistance of the product could be observed.

Comparative Example 7

45% by weight instead of 50% by weight of the Flexflex BT 1040, 45% by weight of 35% by weight of Elvaroi AC 3427, 10% by weight of 15% by weight of Nucre 0903, and alumino siloxane The same procedure as in Example 5 was conducted except that no 10% ethylene methylacrylate (EMA) masterbatch was used.

Table 3 shows the composition ratio and measurement results of each component.

Alumino siloxane was not included, which resulted in a very bad wear.

Comparative Example 8

Instead of 10% ethylene methylacrylate (EMA) masterbatch containing alumino siloxane, Dow Corning's ultra high molecular weight siloxane containing product (MB50-002) containing 50% ultra high molecular weight siloxane (Key50 BT002) was used. It carried out similarly to Example 5 except having used 5 weight part with respect to 100 weight part of the sum total of ElBaroy AC 3427 (EBA) and Nucre 0903.

Table 3 shows the composition ratio and measurement results of each component. In the case of the master batch of ultra high molecular weight siloxane, some of the low molecular weight was contained, the adhesion decreased due to the transition of the low molecular weight even during injection, and due to the low adhesion, it was observed that the delamination during the swelling test was observed. Abrasion was improved due to the addition, but surface migration of low molecular weight body occurred when observed after standing.

Example 5 Example 6 Comparative Example 7 Comparative Example 8 Polyester thermoplastic elastomer (wt%) 50 50 45 50 Ethylene Butylacrylate (wt%) 35 35 45 35 Ethylene Methacrylic Acid Copolymer (wt%) 15 15 10 15 Alumino siloxane containing ethylene methyl acrylate masterbatch (parts by weight) 5 15 - - MB50-002 (parts by weight) - - - 5 Adhesive force (g / cm) 1400 1350 1350 400 Swelling adhesion adhesion adhesion Peeling Implosion No implementation No implementation No implementation Implementation Abrasion Degree (%) 0.3 0.2 2 0.15

The thermoplastic elastomer composition of the present invention has excellent affinity with engineering plastics such as polycarbonate or polyethylene terephthalate, and has excellent interfacial adhesion, so that the double injection is easy, and swelling by oleic acid is minimized, and thus oleic acid resistance is excellent. .

In addition, when used in addition to the alumino siloxane in the present invention, it provides a thermoplastic elastomer composition that is excellent in wear resistance and less surface migration during long-term storage is improved the problem of surface contamination.

Claims (9)

a) 30 to 60% by weight of polyester-based thermoplastic elastomer; b) 30 to 60 wt% of an ethylene acrylate copolymer; And c) 10-30% by weight of unsaturated carboxylic acid ethylene copolymer; Thermoplastic elastomer composition comprising a. The method of claim 1, 100 parts by weight of a) a polyester thermoplastic elastomer, b) an ethylene acrylate copolymer and c) an unsaturated carboxylic acid ethylene copolymer component in total, d) Thermoplastic elastomer composition, characterized in that it further comprises 0.5 to 2 parts by weight of alumino siloxane. The method according to claim 1 or 2, The thermoplastic thermoplastic elastomer has a melting point of 140 to 230 ° C and a Shore hardness of 35 to 62D. The method according to claim 1 or 2, Ethylene acrylate copolymer is a thermoplastic elastomer composition, characterized in that the content of acrylate of 10% to 30% by weight. The method according to claim 1 or 2, Ethylene acrylate copolymer is a thermoplastic elastomer composition characterized in that at least one compound selected from the group consisting of methyl acrylate, ethyl acrylate, butyl acrylate and 2-hydroxyethyl acrylate copolymerized with ethylene. The method according to claim 1 or 2, The content of the unsaturated carboxylic acid of the unsaturated carboxylic acid ethylene copolymer is 7% by weight or more and 20% by weight or less. The thermoplastic elastomer composition according to claim 1 or 2, wherein the thermoplastic elastomer composition is used for double injection molding or double extrusion molding of a molded article made of polycarbonate or polyethylene terephthalate. A molded article obtained by double injection molding or double extrusion molding using the thermoplastic elastomer composition of claim 1 in a molded article made of polycarbonate or polyethylene terephthalate. The method of claim 8, Said molded article being a handle part of a tool or a toothbrush.