阅读说明：本技术 热塑性弹性体树脂组合物 (Thermoplastic elastomer resin composition ) 是由 权材冠 柳振 李哲汉 林容赞 朴相炫 于 2018-12-27 设计创作，主要内容包括：本发明提出一种热塑性弹性体树脂组合物和包含该热塑性弹性体树脂组合物的成型品,所述热塑性弹性体树脂组合物包含热塑性弹性体树脂和反应性添加剂,所述反应性添加剂是含有一个以上的异氰脲酸酯基的化合物。(The present invention provides a thermoplastic elastomer resin composition comprising a thermoplastic elastomer resin and a reactive additive, wherein the reactive additive is a compound having one or more isocyanurate groups, and a molded article comprising the thermoplastic elastomer resin composition.)

1. A thermoplastic elastomer resin composition comprising, based on 100 parts by weight of the composition: 95 to 99 parts by weight of a thermoplastic elastomer resin; and 0.2 to 2.5 parts by weight of a reactive additive which is a compound containing one or more isocyanurate groups.

2. The thermoplastic elastomer resin composition according to claim 1, wherein the thermoplastic elastomer resin comprises a thermoplastic polyester-based elastomer (TPEE), a thermoplastic styrene-butadiene-based elastomer (TPE-S), a Thermoplastic Polyurethane (TPU), or two or more thereof.

3. The thermoplastic elastomer resin composition according to claim 1, wherein the thermoplastic elastomer resin is a thermoplastic polyester-based elastomer (TPEE),

the thermoplastic polyester-based elastomer comprises: a hard segment comprising polymerized units derived from an aromatic dicarboxy compound and a diol; and a soft segment comprising polymerized units derived from a polyalkylene oxide.

4. The thermoplastic elastomer resin composition according to claim 3, wherein the aromatic dicarboxylic compound comprises terephthalic acid, isophthalic acid, 1,5-dinaphthalenedicarboxylic acid, 2,6-dinaphthalenedicarboxylic acid, dimethyl terephthalate, dimethyl isophthalate, or a mixture of two or more thereof;

the diol comprises ethylene glycol, propylene glycol, 1, 4-butanediol, 1, 5-pentanediol, 1, 6-hexanediol, 1, 4-cyclohexanedimethanol, or a mixture of two or more thereof;

the polyalkylene oxide comprises a polyoxyethylene glycol, a polyoxypropylene glycol, a polyoxytetramethylene glycol, or a mixture of two or more thereof.

5. The thermoplastic elastomer resin composition according to claim 3, wherein the thermoplastic polyester-based elastomer is branched by a branching agent comprising glycerol, pentaerythritol, neopentyl glycol or a mixture of two or more thereof.

6. The thermoplastic elastomer resin composition according to claim 1, wherein the compound having one or more isocyanurate groups comprises hexamethylene diisocyanate-isocyanurate, isophorone diisocyanate-isocyanurate, toluene diisocyanate-isocyanurate, 4-cyclohexanedimethanol diisocyanate-isocyanurate, 4' -dicyclohexylmethane diisocyanate-isocyanurate, methylene diphenyl diisocyanate-isocyanurate, or a mixture of two or more thereof.

7. The thermoplastic elastomer resin composition according to claim 1, further comprising 0.05 to 1 part by weight of an antioxidant.

8. The thermoplastic elastomer resin composition according to claim 1, further comprising an additive comprising a light stabilizer, a heat stabilizer, a surface modifier, a lubricant, a reinforcing agent, a dye, a pigment, or a mixture of two or more thereof.

9. A molded article comprising the thermoplastic elastomer resin composition described in any one of claims 1 to 8.

Technical Field

The present invention relates to a thermoplastic elastomer resin composition, and more particularly, to a thermoplastic elastomer resin composition in which the amount of outgas generated during injection molding is reduced.

Background

Thermoplastic elastomer resins are used in various forms in the overall industries of electric and electronic materials, biomaterials, automobile materials, etc., based on excellent heat resistance, chemical resistance, and durability, and are replacing existing materials. In particular, thermoplastic polyester-based elastomer resins are used in automobile parts for constant velocity joint boots, transmission bellows, air ducts, and the like. Such automobile parts are manufactured by blow molding, and the resin is produced by blow molding in a molten state, so that the resin in the molten state should have high melt viscosity and melt strength, and should maintain a parison shape during extrusion blow molding.

To achieve the properties of such blow molding materials, reactive additives are used. When the reactive additive is used, physical properties for blow molding can be achieved, and excellent heat resistance can be imparted to a molded product.

However, the conventional reactive additive has a problem that an unreacted reactive additive may remain in a molded product during reactive extrusion. Residual reactive additives generate outgassing during blow molding and this outgassing gradually accumulates on the mold, which can result in deposits on the mold during repeated production. Such substances deposited on the mold may cause problems in operability such as occurrence of defective injection molding and increase in the number of times of cleaning the mold.

Therefore, there is a need to develop a thermoplastic elastomer resin composition for blow molding which is less likely to cause outgassing and thus solves the problem of deposition on the mold.

Disclosure of Invention

Technical problem to be solved

The invention provides a thermoplastic elastomer resin composition which generates less exhaust gas and improves the operability of injection molding.

Technical scheme

In order to solve such a technical problem, according to an aspect of the present invention, there is provided a thermoplastic elastomer resin composition of the following specific embodiment.

The first embodiment relates to a thermoplastic elastomer resin composition comprising, based on 100 parts by weight of the composition: 95 to 99 parts by weight of a thermoplastic elastomer resin; and 0.2 to 2.5 parts by weight of a reactive additive which is a compound containing one or more isocyanurate groups.

A second embodiment relates to the thermoplastic elastomer resin composition of the first embodiment, the thermoplastic elastomer resin comprising a thermoplastic polyester-based elastomer (TPEE), a thermoplastic styrene-butadiene-based elastomer (TPE-S), a Thermoplastic Polyurethane (TPU), or two or more thereof.

A third embodiment relates to the thermoplastic elastomer resin composition of the first or second embodiment, the thermoplastic elastomer resin being a thermoplastic polyester-based elastomer (TPEE) comprising: a hard segment comprising polymerized units derived from an aromatic dicarboxy compound and a diol; and a soft segment comprising polymerized units derived from a polyalkylene oxide.

A fourth embodiment relates to the thermoplastic elastomer resin composition of the third embodiment, said aromatic dicarboxylic compound comprising terephthalic acid, isophthalic acid, 1,5-dinaphthalenedicarboxylic acid, 2,6-dinaphthalenedicarboxylic acid, dimethyl terephthalate, dimethyl isophthalate, or a mixture of two or more thereof; the diol comprises ethylene glycol, propylene glycol, 1, 4-butanediol, 1, 5-pentanediol, 1, 6-hexanediol, 1, 4-cyclohexanedimethanol, or a mixture of two or more thereof; the polyalkylene oxide comprises a polyoxyethylene glycol, a polyoxypropylene glycol, a polyoxytetramethylene glycol, or a mixture of two or more thereof.

A fifth embodiment relates to the thermoplastic elastomer resin composition of the third or fourth embodiment, the thermoplastic polyester elastomer is branched by a branching agent comprising glycerol, pentaerythritol, neopentyl glycol or a mixture of two or more thereof.

A sixth embodiment is directed to the thermoplastic elastomer resin composition of any one of the first to fifth embodiments, wherein the compound having one or more isocyanurate groups comprises hexamethylene diisocyanate-isocyanurate, isophorone diisocyanate-isocyanurate, toluene diisocyanate-isocyanurate, 4-cyclohexanedimethyl diisocyanate-isocyanurate (4, 4-cyclohexanedimethylene diisocyanate-isocyanurate), 4' -dicyclohexylmethane diisocyanate-isocyanurate, methylene diphenyl diisocyanate-isocyanurate, or a mixture of two or more thereof.

A seventh embodiment relates to the thermoplastic elastomer resin composition of any one of the first to sixth embodiments, further comprising 0.05 to 1 part by weight of an antioxidant.

An eighth embodiment is directed to the thermoplastic elastomer resin composition of any one of the first to seventh embodiments, further comprising an additive comprising a light stabilizer, a heat stabilizer, a surface modifier, a lubricant, a reinforcing agent, a dye, a pigment, or a mixture of two or more thereof.

The ninth embodiment relates to a molded article comprising the thermoplastic elastomer resin composition of any one of the first to eighth embodiments.

Advantageous effects

According to an embodiment of the present invention, a thermoplastic polyester-based elastomer resin composition which is less likely to generate outgas and is improved in the handling property in injection molding, can be produced from an ester elastomer which has been commercialized, and is suitable for blow molding, and has a high viscosity. Further, by reducing the exhaust gas which is a problem of the reactive extrusion, an effect of improving the operability of the blow molding, that is, the prevention of the deposition on the mold, the prevention of the injection molding failure due to the deposition on the mold, and the like can be expected.

Further, according to an embodiment of the present invention, while the problem of mold deposition is improved by reducing the generation of exhaust gas, the mechanical properties are maintained at the same level or more as compared with the prior art, and thus it can be applied to the manufacture of constant velocity joint boots, transmission bellows, air ducts, and the like, which are blow molded products.

Detailed Description

The present invention will be described in detail below. Before this, the terms or words used in the present specification and claims should not be construed as being limited to conventional or dictionary meanings, but interpreted as meanings and concepts conforming to the technical idea of the present invention on the basis of the principle that the inventor can appropriately define the concept of the term to describe his own invention by the best method.

Therefore, the contents shown in the embodiments described in the present specification are only one most preferable embodiment of the present invention and do not represent all the technical ideas of the present invention, and therefore it should be understood that various equivalents and modifications may exist in the present application in place of these.

In addition, "parts by weight" described in the present specification means a weight ratio between components contained in the thermoplastic elastomer resin composition.

The thermoplastic elastomer resin composition of one aspect of the present invention comprises, based on 100 parts by weight of the composition: 95 to 99 parts by weight of a thermoplastic elastomer resin; and 0.2 to 2.5 parts by weight of a reactive additive which is a compound containing one or more isocyanurate groups.

The thermoplastic elastomer resin composition according to an embodiment of the present invention may include a thermoplastic elastomer (TPE) resin as a matrix resin.

The thermoplastic elastomer resin may be used singly or in combination of two or more kinds.

The thermoplastic elastomer resin may include, for example, thermoplastic polyester elastomer (TPEE) including thermoplastic copolyester elastomer, thermoplastic styrene-butadiene elastomer (TPE-S), Thermoplastic Polyurethane (TPU), or a mixture of two or more thereof.

According to a specific embodiment of the present invention, the thermoplastic elastomer resin may use thermoplastic polyester-based elastomer (TPEE), which may be commonly used or may contain a plasticizer to adjust hardness, but the hardness of the thermoplastic polyester-based elastomer is not particularly limited and may be variously selected according to a product to be used.

The thermoplastic polyester-based elastomer is a thermoplastic polymer obtained by Block Copolymerization (Block Copolymerization) of a rigid Hard Segment (Hard Segment) and a flexible Soft Segment (Soft Segment).

According to a specific embodiment of the present invention, the hard segment may include polymerized units derived from an aromatic dicarboxylic compound and a diol, and the soft segment may include polymerized units derived from a polyalkylene oxide.

The aromatic dicarboxylic compound may include Terephthalic Acid (TPA), Isophthalic Acid (IPA), 1,5-Dinaphthalenedicarboxylic Acid (1, 5-NDCA), 2,6-Dinaphthalenedicarboxylic Acid (2,6-Dinaphthalenedicarboxylic Acid, 2,6-NDCA), Dimethyl Terephthalate (DMT), Dimethyl isophthalate (Dimethyl isophthalate), or a mixture of two or more thereof, and in detail, Dimethyl Terephthalate may be used.

The diol may be a linear aliphatic diol having 2 to 8 carbon atoms or a cyclic aliphatic diol having 3 to 8 carbon atoms, and may include, for example, ethylene glycol, propylene glycol, 1, 4-butanediol, 1, 5-pentanediol, 1, 6-hexanediol, 1, 4-cyclohexanedimethanol, or a mixture of two or more thereof, and specifically may be 1, 4-butanediol.

The polyalkylene oxide may include Polyoxyethylene glycol (polyoxybutylene glycol), Polyoxypropylene glycol (polyoxypropylethylene glycol), polyoxytetramethylene glycol (PTMEG), or a mixture of two or more thereof, and in detail, polyoxytetramethylene glycol may be used.

According to one embodiment of the present invention, the thermoplastic polyester-based elastomer may be branched by a Branching Agent (Branching Agent) in order to improve the stability of a chain (strand) when producing the polyester-based elastomer by improving the melt strength, thereby improving the productivity.

The branching agent may contain, for example, Glycerol (Glycerol), Pentaerythritol (Pentaerythritol), neopentyl glycol (Neopentylglycol), or a mixture of two or more thereof, and Glycerol may be used in detail.

The thermoplastic polyester-based elastomer according to one embodiment of the present invention may be generally prepared by melt polymerization consisting of two steps of oligomerization and polycondensation, and may preferably be a branched thermoplastic polyester-based elastomer.

In one embodiment of the present invention, the branched thermoplastic polyester-based elastomer can be prepared by the steps of: the above components are charged into a reactor and then prepared by melt polymerization consisting of two steps of oligomerization reaction which can be carried out at 140-215 ℃ for 3-4 hours and polycondensation reaction which can be carried out at 210-250 ℃ for 4-5 hours, in the presence of a suitable catalyst, for example, tetra-n-butyltitanium (TBT), during which the pressure is gradually reduced from 760 torr to 0.3 torr.

In one embodiment of the present invention, the soft segment content in the thermoplastic polyester-based elastomer may be 5 to 75% by weight, and more specifically, 30 to 70% by weight, based on 100% by weight of the total of the thermoplastic polyester-based elastomer, in consideration of mechanical strength, flexibility, and the like. When the content of the soft segment in the polyester-based elastomer satisfies such a range, the hardness of the thermoplastic polyester-based elastomer is not excessively high, the flexibility is improved, and high heat resistance can be achieved.

According to one embodiment of the present invention, the polyester-based elastomer may have an intrinsic viscosity (intrinsic viscosensitivity) of 1.7 to 2.2dl/g, and in detail, may have an intrinsic viscosity of 1.9 to 2.0 dl/g.

The thermoplastic elastomer resin composition of the present invention contains a compound containing one or more isocyanurate groups as a reactive additive to increase the melt viscosity and melt strength, thereby enabling blow molding.

Specifically, the isocyanurate group is formed by combining three isocyanate compounds, and the thermal stability is very excellent. The isocyanurate group has more reactive groups than existing isocyanate compounds having two or less reactive groups, and thus can form urethane bonds with more chains of the thermoplastic elastomer resin, thus exhibiting more excellent characteristics in terms of increasing molecular weight, and can play a role in improving thermal stability. As a result, by using a compound containing one or more isocyanurate groups as a reactive additive, mechanical properties are improved, viscosity is reduced, and blowing is facilitated.

Further, the reactive additive of the present invention contains one more isocyanurate group than the conventional isocyanate compound, and thus can react with the thermoplastic elastomer resin more, and the possibility of escape of unreacted materials is small, and the compound itself having an isocyanurate group exhibits excellent thermal stability, so that the possibility of deposition of gas generated by decomposition during injection molding on a mold can be reduced.

The compound that can be used as the reactive additive may be used without limitation as long as it contains one or more isocyanurate groups. For example, the compound having one or more isocyanurate groups may include hexamethylene diisocyanate-isocyanurate, isophorone diisocyanate-isocyanurate, toluene diisocyanate-isocyanurate, 4-cyclohexane dimethyldiisocyanate-isocyanurate, 4' -dicyclohexylmethane diisocyanate-isocyanurate, methylene diphenyl diisocyanate-isocyanurate, or a mixture of two or more thereof, but is not limited thereto.

The thermoplastic elastomer resin composition of the present invention comprises 95 to 99 parts by weight of the thermoplastic elastomer resin and 0.2 to 2.5 parts by weight of the reactive additive, based on 100 parts by weight of the composition.

In one embodiment of the present invention, the content of the reactive additive may be in detail 0.3 to 2 parts by weight, more in detail 0.5 to 1 part by weight, based on 100 parts by weight of the composition. When the content of the reactive additive is less than 0.2 parts by weight based on 100 parts by weight of the composition, the melt viscosity is reduced and thus it is difficult to use as a blow molding material, and when the content of the reactive additive exceeds 2.5 parts by weight, the generation amount of outgas increases, deposition on a mold occurs, and the workability of injection molding may be deteriorated.

The thermoplastic elastomer resin composition of the present invention may further comprise an antioxidant to prevent deterioration and oxidation of the thermoplastic elastomer resin during high-temperature injection molding.

The kind of the antioxidant is not particularly limited, and antioxidants generally used in this field can be used without limitation. For example, a hindered amine antioxidant, a hindered phenol antioxidant, a phosphite antioxidant, an amide antioxidant, a thioester antioxidant, or a mixture of two or more thereof may be used as the antioxidant, but not limited thereto.

More specifically, 4 '-bis (α, α -diphenylbenzyl) diphenylamine (4, 4' -bis (α, α -diphenylbenzyl) diphenylamine), octadecyl-3- (3, 5-di-t-butyl-4-hydroxyphenyl) -propionate, or a mixture of two or more thereof may be used as the antioxidant, but the antioxidant is not limited thereto.

The antioxidant may be contained in an amount of 0.05 to 1 part by weight, specifically 0.1 to 0.5 part by weight, based on 100 parts by weight of the composition.

The thermoplastic elastomer resin composition of the present invention may further comprise one or more additives commonly used for thermoplastic elastomer resin compositions, in addition to the above-mentioned components. The additive may be, for example, a light stabilizer, a heat stabilizer, a surface modifier, a lubricant, a reinforcing agent, a dye, a pigment, or a mixture of two or more thereof, but is not limited thereto. Among them, the surface modifier is exemplified by silicone resin, but is not limited thereto. When the surface modifier is mixed with a thermoplastic elastomer resin and injected into a mold, the surface modifier migrates to the surface of the injection molded article and plays a role of protecting the surface, while also having an effect of being more easily released from the injection mold, and thus moldability can be improved.

The content of the additive is not particularly limited, and may be used without limitation within a range not to impair the desired physical properties of the present invention. For example, the additive may be contained in an amount of 0.1 to 5 parts by weight, specifically 0.5 to 3 parts by weight, based on 100 parts by weight of the composition, but is not limited thereto.

The thermoplastic elastomer resin composition of one embodiment of the present invention can be prepared by adding the above thermoplastic elastomer resin, reactive additive, optional antioxidant and optional additive to an extruder, mixing in the extruder and extruding.

The extruder may be a twin-screw extruder or a single-screw extruder, and the L/D (length/diameter) of the extruder may be 20 to 35, but is not limited thereto.

For the extrusion conditions, the extruder temperature can be used at 180 ℃ and 220 ℃ and the RPM can be used at 150 ℃ and 350, but is not limited thereto.

The thermoplastic elastomer resin composition of the present invention prepared as described above has high melt viscosity and melt strength, and thus can be used as a blow molding material.

According to another aspect of the present invention, there is provided a molded article comprising the thermoplastic elastomer resin composition.

The molded article provided according to an embodiment of the present invention may be a boot seal of a constant velocity joint of an automobile, a bellows of a transmission, or an air duct.

Hereinafter, the present invention will be described in detail by referring to examples to assist understanding thereof. However, the examples of the present invention may be modified into various other embodiments, and the scope of the present invention should not be construed as being limited to the examples described below. The embodiments of the present invention are provided to more fully explain the present invention to those skilled in the art.