KR20150055171A - Thermoplastic polyetherester elastomer composition - Google Patents

Abstract

The present invention relates to a thermoplastic polyetherester elastomer composition. The thermoplastic polyetherester elastomer composition includes: a base resin comprising a low hardness polyetherester block copolymer having the shore hardness equal to or lower than 47D, high hardness polyetherester block copolymer having the shore hardness equal to or higher than 57D, and polybutylene terephthalate; and a polyolefin copolymer resin which includes an epoxy group. The TDR value of the thermoplastic polyetherester elastomer composition is higher than 0.95. The present invention applies a TPEE material which has the low-temperature impact performance enhanced by introducing the branched base polymer obtained through a copolymerization process initialed by introducing trifunctional or larger reactive alcohol during the polymerization process of the polyester elastomer. Accordingly, the present invention can increase the apparent molecular weight and disperse the transmitted shock waves, thereby simplifying a vehicle airbag cover structure and increasing the degree of freedom regarding the designs thereof. In addition, the TDR value is a ratio of the peak tangent delta value measured with DTMA under the conditions having the strain load of 1%, dynamic load of 0.1%, contact force of 2.5N, and frequency of 10Hz and the tangent delta values measured in the range of ± 5 °C from the temperature of the peak value.

Description

[0001] Thermoplastic polyetherester elastomer composition [0002]

TECHNICAL FIELD The present invention relates to a thermoplastic polyetherester elastomer composition, and more particularly, to a thermoplastic polyester elastomer composition applicable to automotive parts such as a cover for an airbag device for a vehicle.

Recently, in the field of automobiles, the demand for lighter weight and eco-friendliness has led to the replacement of metal and bridged rubber parts with plastic parts. Accordingly, utilization of thermoplastic elastomer materials which have low specific gravity, good workability and can be recycled is increasing.

Particularly, the polyester-based elastomer has excellent mechanical properties, and is superior to the elastomers of the series having different repetition fatigue, hinge characteristics and long-term durability, and has been widely used in various machine parts and automobile fields.

On the other hand, flexible thermoplastics are used for covers used for driver airbag (DAB) modules. Among them, TPEE and TPO are available. Among them, TPEE is a thermoplastic polyester elastomer, which is generally superior to other elastic materials in terms of performance and stability, and has recently been used in airbag covers and the like.

The polyetherester block copolymer, which is the main constituent of the TPEE, is prepared by melt polycondensation by copolymerization of polybutylene terephthalate (PBT) and polytetra methylene glycol (PTMG). As shown in FIG. 1, (A) (Hard segment) and (B) Soft segment.

In this case, (A) the hard segment maintains the stress transmission and rigidity and maintains the shape when the airbag cover is injected, (B) the soft segment increases energy absorption and flexibility, So that the airbag cover is not scattered even when deployed.

Conventionally, the airbag cover is scattered or broken when the airbag is deployed at a low temperature. To prevent such a problem, the airbag cover is structurally reinforced.

However, since there is a limit to such a structural reinforcement, there is a disadvantage that a proper reinforcing structure should be applied whenever the air bag design is changed. Recently, in order to meet the increasing demand for automobile, Can not be found.

Accordingly, the inventors of the present invention have made efforts to develop a TPEE material having improved low-temperature impact performance through the introduction of the branched base polymer obtained by copolymerizing a reactive alcohol having three or more functional groups when polymerizing a polyester elastomer The present invention has been accomplished by simplifying the structure of the airbag cover and improving the degree of design freedom.

An object of the present invention is a thermoplastic polyetherester elastomer composition in which the apparent molecular weight is increased and the shock wave transmission is dispersed.

Another object of the present invention is a thermoplastic polyetherester elastomer composition which simplifies the structure of the airbag cover and improves the degree of design freedom.

Another object of the present invention is to provide an airbag cover and other automotive parts having improved low-temperature impact resistance by applying the thermoplastic polyetherester elastomer composition.

The above and other objects of the present invention can be achieved by the present invention described below.

One aspect of the present invention is a base resin comprising a low-hardness polyetherester block copolymer having a Shore hardness of 47 D or lower, a high-hardness polyetherester block copolymer having a Shore hardness of 53 D or higher, and polybutylene terephthalate; And a polyolefin copolymer resin having an epoxy group, wherein the TDR has a strain load of 1%, a dynamic load of 0.1%, a contact force of 2.5 N, and a frequency of 2.5 N. The thermoplastic polyetherester elastomer composition has a TDR of 0.95. : The peak value of tangent delta measured with DMTA at 10Hz and the ratio of the tangent delta value in the range of ± 5 ° C at the temperature indicating the peak value).

In one embodiment, the base resin comprises 15 to 65% by weight of a low-hardness polyether ester block copolymer having a Shore hardness of 47 D or less based on 100% by weight of the entire base resin, 20 to 20% by weight of a high- 50% by weight of polybutylene terephthalate and 10 to 40% by weight of polybutylene terephthalate.

In one embodiment, the composition may have a melt viscosity of the resin measured at 250 占 폚 at a shear rate of 1000 1 / s with a capillary melt viscometer according to ASTM D3835 of 150 to 650 psi.

In one embodiment, the base resin may be copolymerized with a reactive alcohol having three or more functional groups, wherein the base resin has a hard segment of the following formula (1) and a soft segment of the following formula (2)

[Chemical Formula 1]

(Wherein D is a radical in which two hydroxyl groups are removed from a mixture of two or more selected from the group consisting of saturated aliphatic diols of C 2 to C 8 and cyclic diols, and R is an aromatic, aliphatic And cyclic dicarboxylic acid, or a mixture in which two carboxyl groups are removed from a mixture of two or more thereof)

(2)

Wherein G is a radical selected from the group consisting of polyether glycols having a molecular weight of 400 to 4,000, or a mixture of two or more thereof, in which two hydroxyl groups have been removed, R is a C2 to C20 aliphatic, Lt; / RTI > hydrocarbon radical).

In one embodiment, the above trifunctional or higher reactive alcohol is at least one selected from the group consisting of glycerin, trimethylol ethane, trimethylol propane, trimethylol butane, trimethylol pentane, or pentaerythritol Or more.

In one embodiment, the polyolefin copolymer resin having an epoxy group may be added in an amount of 1.0 to 5.0 parts by weight based on 100 parts by weight of the polyetherester block copolymer.

In one embodiment, the polyolefin copolymer resin having an epoxy group may be represented by the following formula (3):

 (3)

(Wherein R is a hydrocarbon group having 1 to 20 carbon atoms and x and y are natural numbers of 100,000 or less).

In one embodiment, the composition comprises a stabilizer and the stabilizer is selected from the group consisting of 2,2'-m-phenylene bis (2-oxazoline), 4,4'-bis (?,? Dimethylbenzyldisphenylamine ) And N, N'-hexane-1,6-diylbis (3- (3,5-di-tert-butyl-4-hydroxyphenyl-propionamide) Lt; / RTI >

In one embodiment, the stabilizer may be added in an amount of 0.1 to 1.0 part by weight based on 100 parts by weight of the polyetherester block copolymer.

Another aspect of the present invention relates to an automotive part formed from the thermoplastic polyetherester elastomer composition.

In one embodiment, the automotive component may be a cover for an airbag device for a vehicle.

The thermoplastic polyetherester elastomer composition according to the present invention can be obtained by applying a TPEE material having improved low-temperature impact performance through introduction of the branched base polymer obtained by copolymerizing and introducing a reactive alcohol having three or more functionalities when polymerizing a polyester elastomer , The apparent molecular weight is increased, and the shock wave transmission is dispersed. This has the effect of simplifying the structure of the airbag cover for an automobile and improving the degree of freedom of design.

BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is a schematic view of the general structure of a polyetherester block copolymer ((A) hard segment and (B) soft segment).
Fig. 2 is a schematic view showing one internal structure of the polyetherester block copolymer ((A) hard segment and (B) soft segment).
Fig. 3 is a schematic view showing one internal structure of the polyetherester block copolymer according to the present invention ((A) an enlarged view of a branch chain).

Embodiments of the present application will now be described in more detail with reference to the accompanying drawings. However, the techniques disclosed in the present application are not limited to the embodiments described herein but may be embodied in other forms. It should be understood, however, that the embodiments disclosed herein are provided so that this disclosure will be thorough and complete, and will fully convey the scope of the invention to those skilled in the art. In the drawings, the width, thickness, and the like of the components are enlarged in order to clearly illustrate the components of each device.

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

Thermoplastic polyetherester elastomer composition

The thermoplastic polyetherester elastomer composition, which is one aspect of the present invention, comprises a low-hardness polyetherester block copolymer having a Shore hardness of 47D or lower, a high-hardness polyetherester block copolymer having a Shore hardness of 53D or higher, and polybutylene terephthalate Basic resin; And a polyolefin copolymer resin having an epoxy group and having a TDR of 0.95. The TDR was measured by DMTA under the conditions of strain load: 1%, dynamic load: 0.1%, contact force: 2.5 N, which means the ratio of the peak value of tangent delta value to the tangent delta value in the range of ± 5 ° C at the temperature indicating the peak value).

The thermoplastic polyetherester elastomer composition according to the present invention can be obtained by applying a TPEE material having improved low-temperature impact performance through introduction of the branched base polymer obtained by copolymerizing and introducing a reactive alcohol having three or more functionalities when polymerizing a polyester elastomer The tensile strength, elongation, flexural modulus, tear strength, IZOD impact strength, and TDR value can be improved by increasing the apparent molecular weight and dispersing the shock wave transmission. And excellent horn operability, so that the airbag cover has excellent performance such as no scattering of debris when the airbag cover is deployed.

Each component constituting the thermoplastic polyetherester elastomer composition of the present invention will be described in detail as follows.

(A) Base resin

A) a low-hardness polyetherester block copolymer having a Shore hardness of 47 D or lower, a high-hardness polyetherester block copolymer having a Shore hardness of 53 D or higher, and a polybutylene terephthalate .

Wherein the polyetherester block copolymer is a thermoplastic polyetherester block copolymer having a structure in which a hard segment represented by the following formula (1) and a soft segment represented by the following formula (2) are alternately repeated and copolymerized with a trifunctional or higher reactive alcohol It is cohesive:

[Chemical Formula 1]

(Wherein D is a radical in which two hydroxyl groups are removed from a mixture of two or more selected from the group consisting of saturated aliphatic diols of C 2 to C 8 and cyclic diols, and R is an aromatic, aliphatic And cyclic dicarboxylic acid, or a mixture in which two carboxyl groups are removed from a mixture of two or more thereof)

(2)

Wherein G is a radical selected from the group consisting of polyether glycols having a molecular weight of 400 to 4,000, or a mixture of two or more thereof, in which two hydroxyl groups have been removed, R is a C2 to C20 aliphatic, Lt; / RTI > hydrocarbon radical).

For example, the polyetherester block copolymer is prepared by melt polycondensation by copolymerization of polybutylene terephthalate (PBT) and polytetra methylene glycol (PTMG). As shown in FIGS. 1 and 2, Hard segment and (B) Soft segment.

In this case, (A) the hard segment maintains the stress transmission and rigidity and maintains the shape when the airbag cover is injected, (B) the soft segment increases energy absorption and flexibility, So that the airbag cover is not scattered even when deployed.

3, the polyetherester block copolymer according to the present invention is characterized in that the branched chain is expanded (A), whereby the composition of the present invention can increase the apparent molecular weight, It is possible to disperse the impact wave transmission. That is, the composition of the present invention can be applied to an airbag cover by applying a TPEE material having improved low-temperature impact performance through introduction of the branched base polymer obtained by copolymerizing and introducing a reactive alcohol having three or more functionalities in polymerization of a polyester elastomer, And it has the effect of improving design freedom by overcoming the disadvantage of applying the reinforcing structure to each of the changes of the design of the airbag cover by performing the role of dispersing the shock wave transmission.

In one embodiment, the above trifunctional or higher reactive alcohol is at least one selected from the group consisting of glycerin, trimethylol ethane, trimethylol propane, trimethylol butane, trimethylol pentane, or pentaerythritol Or more.

More specifically, in the present invention, polybutylene terephthalate (PBT) is added to the low-hardness polyetherester block copolymer and the high-hardness polyetherester block copolymer among the polyetherester block copolymers having the above- To form a base resin and use it.

In the present invention, the hardness of the polyetherester block copolymer is measured in terms of surface hardness according to ASTM D-2240, and the unit is expressed by Shore hardness D. In the present invention, the Shore hardness of the low-hardness polyetherester block copolymer is 47D or less, preferably 35 to 47D, and the Shore hardness of the high-hardness polyetherester block copolymer is 53D or more, preferably 53 to 81D .

The content of the polyetherester block copolymer is 15 to 65% by weight of the low-hardness polyetherester block copolymer and 20 to 50% by weight of the high-hardness polyetherester block copolymer, based on 100% by weight of the base resin desirable.

If the content of the low-hardness polyetherester block copolymer is less than 15% by weight based on 100% by weight of the entire base resin, the skin feeling of the air bag cover device for a vehicle becomes very hard. If the content of the low-hardness polyetherester block copolymer exceeds 65% by weight, There is a problem that the characteristic is deteriorated.

On the other hand, if the content of the high-hardness polyetherester block copolymer is less than 20% by weight based on 100% by weight of the entirety of the base resin, strands of the molten resin may not be stably formed during the production of the resin composition, The cover portion of the vehicle airbag cover device may have a tough feeling and there may be a problem that the entire cover is detached from the apparatus when the vehicle airbag cover device is deployed in parallel with the breakage line.

The polybutylene terephthalate is used as a mechanical property enhancing agent to enhance the bending properties of the thermoplastic polyetherester elastomer composition of the present invention. The content of the polybutylene terephthalate resin is preferably 10 to 40% by weight.

If the content of the polybutylene terephthalate resin is less than 10% by weight, it is impossible to expect a significant improvement in mechanical properties, particularly bending properties. If the content of the polybutylene terephthalate resin exceeds 40% by weight, There is a possibility that the entire cover may be detached from the apparatus when the vehicle airbag cover device is deployed in parallel with the unfolded broken line.

(B) a polyolefin copolymer resin

It is preferable to add a polyolefin copolymer resin having an epoxy group in the resin composition in order to increase the compatibility between the resin compositions of the present invention and enhance the workability in a twin screw extrusion kneader.

In one embodiment, the epoxy resin may have the structure:

[Chemical Formula 4]

(In the formula (4), P is a polymer obtained from an olefin having C2 to C12).

Preferably, P in the formula (4) is a copolymer, a terpolymer or a mixture of olefins having different carbon numbers. It is preferable that 1.0 to 5.0 parts by weight of the polyolefin copolymer resin having an epoxy group is added to 100 parts by weight of the polyetherester block copolymer.

When the amount of the polyolefin copolymer resin having an epoxy group is less than 1.0 part by weight, the effect of compatibilizing each resin composition does not occur and the processability is deteriorated. When the amount exceeds 5.0 parts by weight, the melt viscosity of the resin composition to be produced becomes excessively low There is a drawback in that the moldability for producing a final molded product is deteriorated.

In particular, as the polyolefin copolymer resin having an epoxy group in the present invention, a polymer material which is a ternary copolymerization represented by the following formula (3) can be used:

(3)

(Wherein R is a hydrocarbon group having 1 to 20 carbon atoms and x and y are natural numbers of 100,000 or less).

Nucleating agent and stabilizer

In the present invention, in order to improve the durability of the thermoplastic polyetherester elastomer composition, in particular, in order to improve the development characteristics when used in a cover for an airbag device for a vehicle, the polyetherester block copolymer is represented by the following formula Lt; RTI ID = 0.0 > bisphenyl < / RTI > ligand can be added:

[Chemical Formula 5]

(Wherein R 1 and R 2 are each a C 2 to C 20 aliphatic, aromatic or cyclic hydrocarbon radical, and M is an alkali metal such as Li, Na or K having monovalent charge).

The alkali metal salt of a phosphate having a bisphenyl ligand is a compound having a structure represented by the formula (5). Specifically, in the present invention, sodium 2,2'-methylene-bis- (4,6- Di-tert-butylphenyl) phosphate [sodium-2,2'-methylene-bis- (4,6-di-tert-butylphenyl) phosphate] as a nucleating agent.

This has the effect of increasing the crystallization rate and decreasing the size of crystals during the processing of the product by acting as a nucleating agent. In addition, the microcrystal structure is enlarged in the resin composition to maximize the phase separation between the segment and the soft segment while minimizing the transition of the decomposition reaction occurring in the soft segment vulnerable to aging to the neighboring segment, It can play a role of improving.

[Chemical Formula 6]

In the thermoplastic polyetherester elastomer composition of the present invention, the content of sodium 2,2'-methylene-bis- (4,6-di-tert-butylphenyl) phosphate is preferably 100 parts by weight of the polyetherester block copolymer Preferably 0.05 to 3.5 parts by weight, more preferably 0.2 to 0.6 parts by weight.

If the content is less than 0.05 part by weight based on 100 parts by weight of the polyetherester block copolymer, the development responsiveness is poor. If the content is more than 3.5 parts by weight, the entire cover portion of the vehicle airbag cover device becomes harder than necessary, There may be a problem that development does not occur in parallel with improvement.

In one embodiment, the composition comprises a stabilizer and the stabilizer is selected from the group consisting of 2,2'-m-phenylene bis (2-oxazoline), 4,4'-bis (?,? Dimethylbenzyldisphenylamine ) And N, N'-hexane-1,6-diylbis (3- (3,5-di-tert-butyl-4-hydroxyphenyl-propionamide) Lt; / RTI >

In the composition of the present invention, when another stabilizer is added together with sodium 2,2'-methylene-bis- (4,6-di-tert-butylphenyl) phosphate, which is the above-mentioned nucleating agent, So that excellent durability can be exhibited and more effective.

Other stabilizers that may be used in combination with sodium 2,2'-methylene-bis- (4,6-di-tert-butylphenyl) phosphate include 2,2'-m-phenylenebis (2-oxazoline) [2 , 2'-m-phenylene bis (2-oxazoline)], 4,4'-bis (alpha, alpha -dimethylbenzyl-diphenylamine) N, N'-hexane-1,6-diyl bis ((3, 5-di-tert- butyl-4-hyd rophenyl-propionamide 3- (3,5-di-tert-butyl-4-hydroxyphenyl propionamide)].

2,2'-m-phenylenebis (2-oxazoline) is represented by the following formula (7), 4,4'-bis (?,? - dimethylbenzyl-disphenylamine) N, N'-hexane-1,6-diylbis (3- (3,5-di-tert-butyl-4-hyd rophenyl-propionamide)

(7)

[Chemical Formula 8]

[Chemical Formula 9]

In one embodiment, the stabilizer may be added in an amount of 0.1 to 1.0 part by weight based on 100 parts by weight of the polyetherester block copolymer.

More specifically, a stabilizer system comprising sodium 2,2'-methylene-bis- (4,6-di-tert-butylphenyl) phosphate represented by Formula 6 and the other stabilizers represented by Formulas 7 to 9 When used, the content of these is preferably from 0.2 to 0.6 parts by weight of sodium 2,2'-methylene-bis- (4,6-di-tert-butylphenyl) phosphate per 100 parts by weight of the polyetherester block copolymer, 0.1 to 3.0 parts by weight of a stabilizer is preferable.

More preferably, the stabilizer system comprises 0.3 to 0.5 parts by weight of sodium 2,2'-methylene-bis- (4,6-di-tert-butylphenyl) phosphate, 0.1 to 1.0 part by weight of? -M-phenylenebis (2-oxazoline), 0.1 to 1.0 part by weight of 4,4'-bis (?,? - dimethylbenzyldiphenylamine), N, N'- And 0.1 to 1.0 part by weight of 6-diyl bis (3- (3,5-di-tert-butyl-4-hydrophenylpropionamide).

In order to increase the durability of the thermoplastic polyetherester elastomer composition, the above stabilizers should be mixed with and added to the characteristics of the resin. In the present invention, by adding the stabilizer system in the above ratio, the durability of the thermoplastic polyetherester elastomer composition So that the expansion stability of the cover for the vehicle airbag device can be ensured when the vehicle is used for a long period of time.

Among the additives, N, N'-hexane-1,6-diylbis (3- (3,5-di-tert-butyl-4-hyd rophenylpropionamide plays a role of trapping an active radical generated by heat It has an advantage that it exhibits adequate heat resistance and hardly deteriorates the initial color.

When 2,2'-m-phenylenebis (2-oxazoline) and 4,4'-bis (a, a-dimethylbenzyldisphenylamine) are used alone in the additive of the present invention, However, 2,2'-m-phenylenebis (2-oxazoline) shows a synergistic effect in realizing excellent durability when used in the same amount, and in particular, the aging phenomenon of polyetherester block copolymer resin And acts as a decomposer of peroxide generated in the soft segment and acts as a capturing agent of formic acid generated in the decomposition of the soft segment.

When such a stabilizer system is used, durability of about 20 times higher than that of a base composition containing no additional stabilizer can be achieved, which is very superior to the durability of general polyetherester thermoplastic elastomer . In particular, when applied to a vehicle airbag cover, it is possible to prevent scattering of fragments when the cover of the airbag device is deployed even after long-term use, and the stable deployment performance can be maintained.

In one embodiment, the composition has an apparent melt viscosity (Mw) of 150 to 650 Pa < s >, measured at 250 [deg.] C with a capillary melt viscosity meter according to ASTM D3835 at a shear rate of 1000 < ).

It is possible to prevent flash and burrs from being generated due to excessive flow during molding of the product in the above range and to avoid occurrence of defective molding when the flow characteristics of the material pass through a narrow channel, It is possible to prevent the molding failure that the molten material does not pass through the tear seam of the airbag cover.

Automotive parts

Another aspect of the present invention relates to an automotive part formed from the thermoplastic polyetherester elastomer composition.

The thermoplastic polyetherester elastomer composition of the present invention can provide a molded article, which may include, for example, various industrial materials and parts thereof, an air suction device of an automobile, an exhaust device, and a hose have. In the present invention, it may preferably be an automotive part.

In one embodiment, the automotive component may be a cover for an airbag device for a vehicle.

In principle, the airbag system includes an impact sensor and an airbag device that contribute to the collision of the high-speed vehicle. An airbag device is connected to an airbag and an airbag housed in a cavity provided in a front portion of a driver's seat and an assistant seat in a high-speed traveling body, and an inflator for inflating the airbag, a holding device for holding an airbag, an inflator, A cover for protecting the opening of the cavity in which the airbag, the inflator and the holding device are housed, and a horn device located beneath the cover.

The airbag cover system is largely divided into a membrane type and a floating type depending on the manner in which the horn is operated. The membrane type is a configuration in which a horn is provided under a thin and smooth airbag cover, and the horn is designed to operate when the airbag cover surface is pressed , The float system is designed to have a horn at the bottom of the cover module so that the entire cover is pressed to activate the horn.

Therefore, in order to uniformly transmit the pressure applied by the driver's hand to the horn, the floating type cover needs to have higher bending characteristics than the membrane type. On the other hand, there is no particular limitation on the shape of the cover, but there may be a difference in the feeling felt by the occupant and the airbag deployment characteristics in the event of a vehicle collision depending on the materials used.

In principle, the airbag system operates as follows; In the event of a collision, the impact sensor senses the collision, and then the igniter in the inflator is electrically or mechanically ignited. Heat is generated by the ignition action, and gas is generated by burning the gas generating agent. The generated gas is accommodated in a cavity portion which is a space between the holding device, the inflator and the cover, and inflates the airbag by filling the folded airbag.

By the pressure of the expanding airbag, the cover is cracked at a predetermined position, and by expanding to form an opening, the airbag is momentarily released and expanded through the opening toward the front of the occupant. The inflated airbag acts as an impact mitigator to prevent the occupant from colliding with the operating device and suffering injury.

Thus, the airbag cover is essential to the airbag device, so that when the collision occurs and causes gas generation in the airbag system, the cover must be deployed securely without debris that could cause injury to the occupant, allowing immediate airbag release and inflation.

In the present invention, a cover for an air bag apparatus for a vehicle to which the present composition is applied for the above reasons is produced.

The molding may be a blow molding.

The thermoplastic ether ester elastomer composition according to the present invention is manufactured as a cover for an automotive airbag device in vehicle parts, and the manufacturing method is not particularly limited, but preferably it can be manufactured by a blow molding method.

In a specific example, the blow molding is performed by injecting a composition material, air blowing the injected material, opening and closing the air-blown material, cooling the mold-opened material, This is the demolding of the cooled material.

The features and other advantages of the present invention as described above will become more apparent from the following Examples and Comparative Examples. However, the present invention is not limited to the following examples.

Example

For the production of the thermoplastic polyetherester elastomer composition of the present invention, specific specifications of the components used in the following examples and comparative examples are as follows.

(1) Basic resin

- low hardness polyetherester elastomer

Kolon KOPEL KP3339UMHR (polyetherester elastomer, Shore hardness 40D) and Dupont DYM-100 (polyetherester elastomer, Shore hardness 45D) were used.

- High hardness polyetherester elastomer

(Polyetherester elastomer, Shore hardness 72D), Dupont DYM-350 (polyetherester elastomer, Shore hardness 55D), KOPEL KP3355UMHR (polyetherester elastomer 55D), KOPEL KP3363HR (polyetherester elastomer, Shore hardness 63D), KOPEL KP3372 Ether ester elastomer, Shore hardness 55D), and Ticona's Vandar 9116 (polyetherester elastomer, Shore hardness 57D).

- polybutylene terephthalate

SPEIN KP210 (polybutylene terephthalate, Shore hardness 78D) from Kolon was used.

(2) Polyolefin copolymer resin

AX8900 (polyethylene-methyl acrylate-glycidyl methacrylate) from ATOFINA was used.

Example 1

40% by weight of a polyetherester thermoplastic elastomer resin KOPEL KP3355UMHR of Kolon Co., Ltd. having a surface hardness of 40.5 D and a surface hardness of 55.5 D, and 15.5% by weight of a polybutylene terephthalate resin SPESIN KP210 4 parts by weight of ATOFINA AX8900, a polyethylene-methyl acrylate-glycidyl methacrylate terpolymer, were mixed in a tumbler mixer for 1 hour to 100 parts by weight.

0.5 part by weight of sodium 2,2'-methylene-bis- (4,6-di-tert-butylphenyl) phosphate as a nucleating agent and 0.5 part by weight of N, N'-hexane- , 0.5 part by weight of 6-diyl bis (3- (3,5-di-tert-butyl-4-hydroxyphenylpropionamide) and 0.5 part by weight of 2,2'-m-phenylenebis And melt-kneaded through a twin-screw extruder (Twin screw extruder) to prepare a resin composition.

At this time, the temperature of the extruder was set to 150 ° C, 200 ° C, 220 ° C, 230 ° C and 250 ° C in order from the first inlet to the die, and the screw was rotated at 230 RPM.

Then, the mixed resin was solidified in a cooling bath having a temperature of 35 DEG C while being discharged onto a strand, and then a pelletized product was obtained through a pelletizer.

Examples 2 to 5

A thermoplastic polyetherester elastomer composition of the present invention was prepared in the same manner as in Example 1 except that the composition and the ratio were set forth in Table 1 below to obtain a pelletized product.

Comparative Examples 1 to 15

A thermoplastic polyetherester elastomer composition of the present invention was prepared in the same manner as in Example 1 except that the composition and the ratio were set forth in Table 1 below to obtain a pelletized product.

division A B C D E F G H Example One 44.5 40 0 0 15.5 0 0 0 2 51 25 0 0 24 0 0 0 3 39 28 0 0 33 0 0 0 4 42 35 0 0 23 0 0 0 5 50 32 0 0 18 0 0 0 Comparative Example One 0 55 0 45 0 0 0 0 2 65 0 0 35 0 0 0 0 3 0 56 0 44 0 0 0 0 4 51 0 0 49 0 0 0 0 5 100 0 0 0 0 0 0 0 6 0 48 0 52 0 0 0 0 7 0 62 0 38 0 0 0 0 8 45 0 0 0 55 0 0 0 9 0 100 0 0 0 0 0 0 10 0 0 100 0 0 0 0 0 11 0 0 0 100 0 0 0 0 12 0 0 0 0 0 100 0 0 13 0 0 0 0 0 0 100 0 14 0 0 0 0 0 0 0 100 15 0 50 50 0 0 0 0 0

(Unit: wt%)

(Furtherance)

A: Kolon KOPEL KP3339UMHR (polyetherester elastomer, Shore hardness 40D)

B: Kolon KOPEL KP3355UMHR (polyetherester elastomer, Shore hardness 55D)

C: Kolon KOPEL KP3363HR (polyetherester elastomer, Shore hardness 63D)

D: Kolon KOPEL KP3372 (polyetherester elastomer, Shore hardness 72D)

E: Kolon SPESIN KP210 (polybutylene terephthalate, Shore hardness 78D)

F: Dupont DYM-100 (polyetherester elastomer, Shore hardness 45D),

G: Dupont DYM-350 (polyetherester elastomer, Shore hardness 55D)

H: Ticona Vandar 9116 (polyetherester elastomer, Shore hardness 57D)

Experimental Example

The thermoplastic polyetherester elastomer composition prepared from Examples 1 to 5 and Comparative Examples 1 to 15 was dried at 100 ° C for 5 hours by using a dehumidifying type hot air drier to remove moisture, A cover for an airbag device for a vehicle was molded and evaluated as follows, and the results are shown in the following Tables 2 to 3.

The concrete physical property measurement method is as follows;

How to measure property

(1) Tensile strength: A TYPE IV specimen was measured at a speed of 500 mm / min according to ASTM D638, and the unit thereof was MPa.

(2) Elongation ratio: According to ASTM D638, a TYPE IV specimen was measured at a speed of 500 mm / min and its unit is%.

(3) Flexural modulus: A specimen having a size of 127 x 12.7 x 6.4 mm was measured at a speed of 30 mm / min according to ASTM D790, and its unit is MPa.

(4) Tear strength: A DIE C specimen was measured at a speed of 500 mm / min according to ASTM D638, and its unit is kgf / cm.

(5) IZOD Impact Strength: A 63.5 × 12.7 × 6.4 NOTCH specimen was measured according to ASTM D638 and expressed in the form of NB (Non break) and B (Break).

(6) TDR: Strain load: 1%, Dynamic load: 0.1%, Contact force: 2.5N, Frequency: 10Hz And the ratio of tangent delta to the value of tangent delta was measured.

(7) Method of evaluating horn performance: A module was constructed with components such as an inflator and an airbag by injection-molded airbag cover, and the manufactured module was fixed to a holding device made of iron. And then, Each module was maintained in a thermostat for 1 hour after the temperature in the thermostat reached constant temperature, and then evaluated whether it operated normally when the horn of the airbag module was operated at that temperature.

(8) Method of evaluating the development of the airbag cover: A module was formed together with components such as an inflator and an airbag by injection-molded airbag cover, the module was fixed to a holding device made of iron, And the mixture was injected into a thermostat kept at 85 ° C. Each module was kept in a thermostatic chamber for one hour after the temperature in the thermostat reached constant temperature. After that, the module was taken out of the thermostat, the trestle was mounted, and the airbag was deployed by igniting the ignition agent in the inflatable . Evaluation of the expansion characteristics is made by evaluating that the development crack of the airbag cover deployed in the above order is made in a tear seam and that the expansion characteristic is excellent when the broken piece does not scatter during development, And evaluated as poor.

[Table 2]

[Table 3]

Physical property measurement result

As a result of measurement of the basic physical properties of the thermoplastic polyetherester elastomer composition according to the present invention, when the airbag cover for a vehicle is manufactured using the composition of the present invention as shown in Tables 2 to 3, tensile strength, elongation, flexural modulus, The tear strength, the IZOD impact strength, and the TDR value, and also shows excellent performance such as good horn operability and particularly, no scattering of debris when the airbag cover is deployed.

As described above, the thermoplastic polyetherester elastomer composition according to the present invention and the airbag cover for an automobile manufactured using the thermoplastic polyetherester elastomer composition according to the present invention are characterized in that, in the polymerization of the polyester elastomer, By applying the TPEE material having improved low-temperature impact performance through the introduction of the base polymer, the apparent molecular weight is increased and the shock wave transmission is dispersed, thereby providing an effect of simplifying the structure of the automotive airbag cover and improving the degree of design freedom See Tables 2 to 3 above).

While the invention has been shown and described with reference to certain preferred embodiments thereof, it will be understood by those of ordinary skill in the art that various changes in form and details may be made therein without departing from the spirit and scope of the invention as defined by the appended claims. This is possible.

Therefore, the scope of the present invention should not be limited by the described embodiments, but should be determined by the scope of the appended claims as well as the appended claims.

Claims (11)

a) a base resin composed of a low-hardness polyetherester block copolymer having a Shore hardness of 47D or less, a high-hardness polyetherester block copolymer having a Shore hardness of 53D or more, and polybutylene terephthalate; And
b) a polyolefin copolymer resin having an epoxy group;
/ RTI >
Thermoplastic polyetherester elastomer composition with TDR > 0.95:
(The above TDR shows the peak value and the peak value of tangent delta measured by DMTA under the conditions of 1% strain load, 0.1% dynamic load, 2.5 N contact force, and 10 Hz frequency. tangent delta value).
The method according to claim 1,
Wherein the a) base resin comprises 15 to 65% by weight of a low-hardness polyether ester block copolymer having a Shore hardness of 47 D or less based on 100% by weight of the base resin as a whole, 20 to 50% by weight of a high-hardness polyetherester block copolymer having a Shore hardness of 53 D or more, And 10 to 40% by weight of polybutylene terephthalate, based on the total weight of the thermoplastic polyetherester elastomer composition.
The method according to claim 1,
Wherein the composition has a melt viscosity of 150 to 650 Pa · s as measured by a capillary viscometer according to ASTM D3835 at a shear rate of 1000 1 / s at 250 ° C.
The method according to claim 1,
The thermoplastic polyetherester elastomer composition according to any one of claims 1 to 3, wherein the base resin (a) comprises a hard segment of the following formula (1) and a soft segment of the following formula (2) and is copolymerized with a trifunctional or higher reactive alcohol.
[Chemical Formula 1]

(Wherein D is a radical in which two hydroxyl groups are removed from a mixture of two or more selected from the group consisting of saturated aliphatic diols of C 2 to C 8 and cyclic diols, and R is an aromatic, aliphatic And cyclic dicarboxylic acid, or a mixture in which two carboxyl groups are removed from a mixture of two or more thereof)
(2)

Wherein G is a radical selected from the group consisting of polyether glycols having a molecular weight of 400 to 4,000, or a mixture of two or more thereof, in which two hydroxyl groups have been removed, R is a C2 to C20 aliphatic, Lt; / RTI > hydrocarbon radical).
5. The method of claim 4,
The above-mentioned trifunctional or higher reactive alcohol is a combination of at least one member selected from the group consisting of glycerin, trimethylol ethane, trimethylol propane, trimethylol butane, trimethylol pentane, and pentaerythritol Wherein the thermoplastic polyetherester elastomer composition is a thermoplastic polyetherester elastomer composition.
The method according to claim 1,
The thermoplastic polyetherester elastomer composition according to claim 1, wherein the polyolefin copolymer resin having an epoxy group is added in an amount of 1.0 to 5.0 parts by weight based on 100 parts by weight of the polyetherester block copolymer.
The method according to claim 1,
The thermoplastic polyetherester elastomer composition according to claim 1, wherein the polyolefin copolymer resin having an epoxy group (b)
(3)

(Wherein R is a hydrocarbon group having 1 to 20 carbon atoms and x and y are natural numbers of 100,000 or less).
The method according to claim 1,
The composition comprises a stabilizer, wherein the stabilizer is selected from the group consisting of 2,2'-m-phenylene bis (2-oxazoline), 4,4'-bis (?,? Dimethylbenzyldisphenylamine) (3- (3,5-di-tert-butyl-4-hydroxyphenyl-propionamide)) and a mixture of two or more selected from the group consisting of , A thermoplastic polyetherester elastomer composition.
9. The method of claim 8,
Wherein the stabilizer is added in an amount of 0.1 to 1.0 part by weight based on 100 parts by weight of the polyetherester block copolymer.
An automotive part formed from the thermoplastic polyetherester elastomer composition of any one of claims 1 to 9.
11. The method of claim 10,
Characterized in that the component is a cover for an airbag device for a vehicle.

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