KR102463837B1 - Thermoplastic elastic resin composition and product prepared by the same - Google Patents

Abstract

The present invention relates to a thermoplastic elastic resin composition and a molded article prepared therefrom, and more particularly, to a thermoplastic elastic resin composition with improved electrical insulation and heat dissipation properties, and a molded article manufactured therefrom.
The thermoplastic elastic resin composition is characterized in that it comprises a mixture of a polyether ester block copolymer and boron nitride (Boron Nitrdie) having different diameters.
The thermoplastic elastic resin composition of the present invention can provide a molded article having excellent mechanical properties, electrical insulation and heat dissipation properties by adding boron nitride as an elastic material having excellent elasticity and heat resistance.

Description

Thermoplastic elastic resin composition and molded article prepared therefrom {Thermoplastic elastic resin composition and product prepared by the same}

The present invention relates to a thermoplastic elastic resin composition and a molded article prepared therefrom, and more particularly, to a thermoplastic elastic resin composition with improved electrical insulation and heat dissipation properties, and a molded article manufactured therefrom.

Recently, with the development of IT technology, wearable devices have been developed and related technologies have been developed. A wearable device means an electronic device in the form of an accessory that can be worn, such as glasses, a watch, and clothes, and a thermoplastic elastic material is used as a material so that a user can wear it as a part of the body and use it.

Thermoplastic elastic materials refer to various types of thermoplastic elastomers (TPE) such as styrene type, urethane type, olefin type, and amide type. It has both the properties of elastic materials and the thermoplastic properties of general plastic materials.

In particular, polyester-based elastomers have excellent mechanical properties and, above all, have been widely used in various mechanical parts and automobile fields, as they have excellent repeated fatigue, hinge properties, and long-term durability compared to other series of elastomers.

However, in general, in the case of polyether ester elastomer resins, due to the polyether-based polyol used to realize the properties of the elastomer, the melting point is low and the heat resistance is also poor. There is a problem of discoloration. In addition, polymer materials, including elastomers, contain a large amount of various types of volatile substances, which causes odors or releases harmful substances to the human body. There are also problems that cannot be done.

Accordingly, various methods have been proposed to improve the heat resistance and weather resistance of the polyether ester elastomer resin. U.S. Patent Publication No. 3,723,427 discloses a method of applying a tris (hydroxybenzyl) cyanurate-type stabilizer, which is a hindered phenol-based primary heat-resistant agent, and in U.S. Patent Publication No. 3,758,579, a thioester ( Thioester) type secondary heat-resisting agent was presented, and a method of mixing with phenol-based primary heat-resisting agent was disclosed. In U.S. Patent Publication No. 4,414,408, two types of stabilizers were mixed to achieve a synergistic effect of improving the stability of the thermoplastic polyester elastomer resin, and in U.S. Patent Publication No. 4,405,749, 1,3,5-tris-( The stability of polyester resins was evaluated using the ester of 2-hydroxyethy1)-s-triazine-2,4,6-(1H,3H,5H)trion) and 3,5-di-t-buty1-4-hydroxyhydrocinnamic acid. A method for improving has been disclosed.

However, there is a difficulty in meeting the heat dissipation characteristics, electrical insulation, mechanical strength, etc. required in a wearable device as a polyether ester resin of the prior art, and metals such as aluminum nitride (AIN) were mainly used. However, there is a problem in that AIN is easily hydrolyzed by moisture in the air, so that aluminum hydroxide is formed on the surface and negatively affects electronic devices.

Accordingly, the present inventors have made diligent efforts to solve the above problems. As a result, boron nitride (BN) is used as a filler for improving electrical insulation and heat dissipation properties, and in particular, a mixture and dispersant of boron nitride having different diameters. By using, a thermoplastic elastic resin composition excellent in electrical insulation and heat dissipation properties was confirmed, and the present invention was completed.

Accordingly, an object of the present invention is to provide a thermoplastic elastic resin composition having excellent electrical insulation and heat dissipation properties, and having rubber-like elasticity, and a molded article manufactured therefrom.

A first preferred embodiment of the present invention for solving the above problems is a polyether ester block copolymer; And it provides a thermoplastic elastic resin composition comprising a mixture of boron nitride (Boron Nitrdie), and comprising 0.2 to 5% by weight of a dispersing agent including a compound having a silane group, based on the total weight of the composition.

The thermoplastic elastic resin composition according to the first embodiment, based on the total weight, 35 to 75% by weight of the polyether ester block copolymer; 25 to 65% by weight of a mixture of boron nitrides of different diameters; and 0.2 to 5 wt% of a dispersant.

The polyether ester block copolymer according to the first embodiment has a Shore hardness of 25 to 40D or less, and a melt flow index of 5g/10min to 30g/10min when measured as 2.16kg at 230°C according to ISO 1133 standard. can

The boron nitride mixture according to the first embodiment may be a mixture of boron nitride having a small diameter and boron nitride having a diameter of 10 to 25 times the diameter of the small diameter boron nitride.

The boron nitride mixture according to the first embodiment may be a mixture of boron nitride having a diameter of 10 to 20 μm and boron nitride having a diameter of 200 to 300 μm.

The boron nitride mixture according to the first embodiment may be a mixture of boron nitride having a diameter of 10 to 20 μm and boron nitride having a diameter of 200 to 300 μm in a weight ratio of 70:30 to 85:15. connect.

The boron nitride according to the first embodiment may be a plate-shaped boron nitride.

Another preferred embodiment according to the present invention is to provide a molded article manufactured by the thermoplastic elastic resin composition.

The thermoplastic elastic resin composition according to the present invention may have excellent electrical insulation and heat dissipation properties in addition to excellent mechanical properties.

In addition, the molded article prepared from the thermoplastic elastic resin composition according to the present invention can be applied to products requiring excellent electrical insulation and heat dissipation performance.

A first embodiment of the present invention is a polyetherester block copolymer; And it provides a thermoplastic elastic resin composition comprising a mixture of boron nitride (Boron Nitrdie).

Hereinafter, the present invention will be described in more detail.

[Polyether ester block copolymer]

Polyether ester block copolymer (Thermoplastic polyester Elastomer; TPEE) is composed of a hard segment (hard segment, straight chain) composed of diol and dicarboxylate (or dicarboxylic acid) and polyalkylene oxide containing an ester group It consists of a soft segment (soft chain) that becomes It may be a copolymer obtained by combining them.

The diol may include butanediol (butylene glycol), monoethylene glycol, diethylene glycol, propylene glycol and neopentyl glycol, and the dicarboxylate (or dicarboxylic acid) is dimethyl terephthalate, terephthalic acid, dimethyl Isophthalate, isophthalic acid, dimethylnaphthalate, naphthalenedicarboxylic acid, adipic acid and sebacic acid may be applied, and the polyether-based polyol is polyalkylene oxide such as polytetramethylene glycol, polyethylene glycol and polypropylene glycol. can be applied.

The polyether ester block copolymer is not particularly limited as long as it has the characteristics of an elastomer, but specifically, it has a hard segment of butanediol and dimethyl terephthalate and a soft segment of polyoxytetramethylene glycol (PTMG). desirable.

The hardness of the polyether ester block copolymer may be controlled by a polyalkylene oxide containing a soft segment (soft chain) and an ether group, preferably based on the total weight of the polyether ester block copolymer, polyalkylene By including the oxide in an amount of 40 to 80% by weight, the surface hardness of the polyether ester block copolymer is measured as ASTM D2240, Shore 25D to 40D, and in consideration of moldability, it is measured as 2.16kg at 230°C according to ISO 1133. In this case, it is advantageous to set the melt flow index to be 5 g/10 min to 30 g/10 min.

The polyether ester block copolymer may be advantageous in that it is possible to maintain electrical insulation and heat dissipation performance along with excellent elasticity in an amount of 35 to 75% by weight based on the total weight of the thermoplastic elastic resin composition. When the content of the polyether ester block copolymer is less than 35% by weight, the content of boron nitride is high, so electrical insulation and heat dissipation performance are high, but excellent elasticity cannot be maintained. It has the disadvantage of low insulation and heat dissipation performance.

[Boron nitride]

Boron nitride is an inorganic material with excellent electrical insulation and heat dissipation properties. It has excellent chemical stability and strong physical properties against thermal shock. It is a ceramic having the insulating properties of boron nitride and a non-oxide-based ceramic having thermal conductivity similar to that of a metal. In addition, it has high dielectric breakdown strength and resistance, so it can be used as an electrical insulator. It is used as an electrical insulator such as a semiconductor substrate, a transparent glass window of a microwave oven, and a fuel cell, and can be used as a filler for insulation and heat dissipation. Although boron nitride has a tetragonal structure similar to graphite, it is an insulator superior to graphite or other thermally conductive carbon materials.

The boron nitride is uniformly dispersed in the polyether ester block copolymer (TPEE) to exhibit electrical insulation and heat dissipation properties.

The boron nitride may be of plate-shaped and needle-shaped, but preferably made of plate-shaped. When the boron nitride is formed in a plate shape, it is easier to form a conductive network compared to a needle type, and there is an advantage that excellent heat dissipation characteristics can be exhibited.

When the boron nitride is mixed with the polyether ester block copolymer, boron nitride having a constant diameter can be independently used, but using a mixture of boron nitride having different diameters realizes electrical insulation and heat dissipation properties can be effective in

The boron nitride mixture may be used by mixing two or more types of boron nitride having different diameters, and boron nitride having a diameter of 10 to 25 times the diameter of a small diameter boron nitride and a small diameter boron nitride. It is preferable to mix, and it is more preferable to use a mixture of boron nitride having a diameter of 10 to 20 μm and boron nitride having a diameter of 200 to 300 μm, and boron nitride having a diameter of 10 to 20 μm and a diameter of 10 to 20 μm. It is more preferable that 200 to 300 μm of boron nitride is mixed in a weight ratio of 70:30 to 85:15.

When the boron nitride satisfies the weight ratio, the contact area and volume fraction present in the volume of the polyether ester block copolymer can be increased, so that the conductive network can be improved, and the conductivity and heat dissipation performance can be improved.

In addition, the boron nitride is preferably 25 to 65% by weight based on the total weight of the thermoplastic elastic resin composition in view of the mechanical properties of the thermoplastic elastic resin and the ease of pressure and injection molding, in particular, it is more advantageous to obtain electrical insulation and heat dissipation performance can

[Dispersant]

The dispersant is for improving the dispersibility of boron nitride in the polyether ester block copolymer, and may include a compound having a silane group. The dispersant is preferably a compound having a structure in which at least one of an epoxy, a carboxyl, and an amine functional group is bonded to a silane group.

In the dispersant, the terminal functional group of the polyether ester block copolymer reacts with at least one functional group of an epoxy group, a carboxyl group, and an amine group, and a silane group reacts with boron nitride at the same time as the interface between the polyether ester block copolymer and boron nitride There is an advantage in that it is possible to simultaneously realize electrical properties and improve mechanical properties by improving the bonding force. In addition, the dispersant is preferably a compound having a structure in which an epoxy group or a carboxyl group functional group and a silane group are bonded compared to an amine group in terms of improving the interfacial bonding strength between the polyether ester block copolymer and the boron nitride.

When the dispersing agent is included in the thermoplastic elastic resin composition in order to improve the dispersibility of the thermoplastic elastic resin, it may be advantageous to effectively disperse the thermally conductive filler to be included in an amount of 0.2 to 5 parts by weight based on the total weight of the composition.

The thermoplastic elastic composition of the present invention may include a heat resistance agent, an antioxidant, a light stabilizer, a release agent, a compatibilizer, a dye, a pigment, a colorant, a plasticizer, an impact modifier, a stabilizer, a lubricant and these It may further include one or more additives selected from the group consisting of a mixture of.

The heat resistance agent is a heat stabilizer for enhancing the durability of the thermoplastic elastic resin composition, and the use of a hindered phenol-based heat resistance agent serves as an antioxidant while enhancing the durability of the thermoplastic elastic resin composition. preferred in The heat resistant agent may further comprise 0.05 to 0.5 wt% based on the total weight of the thermoplastic elastic focusing composition.

The hindered phenol-based heat resistant agent is pentaerythritol tetrakis-(methylene)-(3,5 di-tert-butyl-4-hydroxyl Phenyl (hydroxy phenyl) propionate (propionate)) can be used, and more specifically, the heat resistant agent is 2,2'-m-phenylene bis (2-oxazoline) [2,2'-m-phenylene bis (2-oxazoline)], 4,4'-bis(α,α-dimethylbenzyl-disphenylamine)[4,4'-bis(alpha, alpha-dimethylbenzyl diphenylamine)] and N,N'-hexane-1 , 6-diyl bis (3- (3,5-di-tert-butyl-4-hydrocyphenyl-propionamide [N, N'-hexane-1,6-diyl bis (3- (3,5-di -tert-butyl-4-hydroxyphenyl propionamide)] may be one or a mixture of two or more selected from the group consisting of, but is not necessarily limited thereto.

The antioxidant may be selected from a phenol type, a phosphite type, a thioether type, and an amine type. may be, but is not necessarily limited thereto.

Accordingly, the present invention exhibits mechanical properties while ensuring electrical insulation and heat dissipation performance, and is advantageous for injection and extrusion molding processing, and molded products requiring electrical insulation and heat dissipation performance, particularly housings of electronic products, or wearable devices requiring elasticity, It is possible to provide a polyether ester block copolymer resin composition that is easy to manufacture for export-type parts and a molded article manufactured therefrom.

The molded article has a surface resistance of 10 ¹⁴ Ω/□ or more, a thermal conductivity of 0.7 W/mK or more, and a flexural modulus of 50 MPa or more, which is excellent in electrical insulation and heat dissipation characteristics. More excellently, the surface resistance is 10 ¹⁴ Ω/□ or more, the thermal conductivity is 0.7 W/mK or more, the flexural modulus is 50 MPa or more, and the Izod impact strength at room temperature (23°C) can realize even the physical properties of NB. can

[Example]

Hereinafter, the present invention will be described in more detail through examples. These examples are only for illustrating the present invention in more detail, and the present invention is not limited thereto.

Examples 1 to 6 and Comparative Examples 1 to 10

A polyether ester block copolymer (KOPEL ^® KP3328, KOPEL ^® KP3355, Kolon Plastics Co., Ltd.) having a surface hardness of 28D or 55D was added to the main hopper, and boron nitride was added to the main hopper by a tumbler mixer as shown in Table 1 below. and mixed for 5 minutes. Then, the thermoplastic elastic resin composition was prepared by melt-kneading through a twin screw extruder. At this time, the temperature of the extruder was set to 100 ℃, 150 ℃, 180 ℃, 200 ℃, 220 ℃ in the order from the first inlet to the die, the rotation speed of the screw was performed under the condition of 230 RPM.

Item
A
(weight%) B
(weight%) C
D
(weight%) E
(weight%) content
(weight%) C-1
(content ratio) C-2
(content ratio) C-3
(content ratio) Example One 67 - 30 15 0 - 3 Example 2 57 - 40 15 0 - 3 Example 3 - 50 15 0 - 3 Example 4 - 50 70 30 0 - 3 Example 5 37 - 15 0 - 3 Example 6 - 20 15 - - 3 Example 7 27 - 70 15 - - 3 Example 8 - 50 15 - - 3 Example 9 - 50 - 15 - 3 comparative example One - 50 100 - 0 - 3 comparative example 2 - 50 - 100 0 - 3 comparative example 3 - 0 - - 0 50 3 comparative example 4 - 50 15 0 - 0

delete

- A: Polyether ester block copolymer (KOPEL ^® KP3328)

delete

- B: polyether ester block copolymer (KOPEL ^® KP3355)

- C: boron nitride mixture

- C-1: boron nitride (Momentive, size 15㎛) content ratio

- C-2: boron nitride (Momentive, size 250㎛) content ratio

- C-3: boron nitride (Momentive, size 100-150㎛) content ratio

- D: Graphene nanoplate (XG science M grade, size: 25 ㎛)

- E: Dispersant (Dow corning Z-6040 silane, epoxy silane)

Physical property evaluation

After the thermoplastic elastic resin composition prepared in Examples and Comparative Examples was discharged onto a strand and solidified in a cooling bath having a temperature of 35 ° C., it was obtained as a pelletized product through a pelletizer, The surface resistance, thermal conductivity, impact strength, and flexural modulus were measured based on the following method.

(1) Surface resistance: Measured according to JIS 7194.

(2) Thermal conductivity: Measured according to ASTM E 1530.

(3) Impact strength: measured according to ASTM D256.

(4) Flexural modulus: measured by ISO 175.

division surface resistance
(Ω/□) thermal conductivity
(W/mK) Izod impact strength
(J/m) 23℃ flexural modulus
(MPa) Example One ~10 ¹⁶ 0.7 NB 51 2 ~10 ¹⁵ 0.9 NB 61 3 ~10 ¹⁵ 1.1 NB 4 ~10 ¹⁵ 1.4 NB 83 5 ~10 ¹⁴ 1.6 NB 76 6 ~10 ¹⁶ 0.4 NB 7 ~10 ¹⁵ 91.3 53 8 ~10 ¹⁵ 1.1 30.2 128 9 ~10 ¹⁵ 0.6 NB comparative example One ~10 ¹⁵ 0.5 NB 67 2 ~10 ¹⁶ - NB 3 ~10 ⁸ 0.6 NB 4 ~10 ¹⁵ 0.5 NB 32

As the physical property measurement results are shown in Table 2, the dispersing agent containing the compound having a silane group while including the polyether ester block copolymer and boron nitride through Examples 1 to 9 according to the present invention is adjusted to the optimum range. It was confirmed that excellent surface resistance, thermal conductivity, and flexural modulus were secured by including.

On the other hand, in Comparative Examples 1 and 2, boron nitride having one diameter was used, and it was confirmed that the thermal conductivity was low or not measured, so that it did not meet the required level.

In Comparative Example 3, when graphene nanoplates were used instead of boron nitride, it was confirmed that the surface resistance was lowered and the electrical insulation was lowered.

In Comparative Example 4, although the same filler was added, it was confirmed that the dispersion of the filler was not even when the dispersing agent was not used, so that the surface resistance did not come out evenly and the flexural modulus was lowered.

The above description of the present invention is for illustration, and those of ordinary skill in the art to which the present invention pertains can understand that it can be easily modified into other specific forms without changing the technical spirit or essential features of the present invention. will be. Therefore, it should be understood that the embodiments described above are illustrative in all respects and not restrictive.

Claims (8)

polyetherester block copolymers; Comprising a dispersing agent comprising a compound having a boron nitride (Boron Nitrdie) mixture and a silane group,
The polyether ester block copolymer includes a hard segment of butanediol and dimethyl terephthalate and a soft segment of polyoxytetramethylene glycol,
The boron nitride mixture is a thermoplastic elastic resin composition that is a mixture of boron nitride having a diameter of 10 to 20 μm and boron nitride having a diameter of 200 to 250 μm in a weight ratio of 70:30 to 85:15. According to claim 1, wherein the thermoplastic elastic resin composition, based on the total weight based on the polyether ester block copolymer 35 to 75% by weight; 20 to 60% by weight of a mixture of boron nitride; and 0.2 to 5 wt% of a dispersant. The method according to claim 1, wherein the polyether ester block copolymer has a Shore hardness of 25 to 40D or less, and a melt flow index of 5g/10min to 30g/10min when measured as 2.16kg at 230°C according to ISO 1133 standard. A thermoplastic elastic resin composition comprising The thermoplastic elastic resin according to claim 1, wherein the boron nitride mixture is a mixture of boron nitride having a small diameter and boron nitride having a diameter 10 to 25 times larger than that of the small diameter boron nitride. composition. delete delete The thermoplastic elastic resin composition according to claim 1, wherein the boron nitride is plate-shaped boron nitride. A molded article manufactured by the thermoplastic elastic resin composition of any one of claims 1 to 4, and claim 7.