KR20190080603A - Thermoplastic resin composition and molded product using the same - Google Patents

Abstract

The present invention relates to a thermoplastic resin composition and a molded article using the same, wherein the thermoplastic resin composition comprises: (A) 50 to 90 wt% of a polybutylene terephthalate resin; and (C) 1 to 10 parts by weight of an ethylene-glycidyl methacrylate-based graft copolymer, based on 100 parts by weight of a base resin comprising (B) 10 to 50 wt% of an acrylic graft copolymer. The thermoplastic resin composition according to an embodiment can manufacture the molded article excellent in weather resistance, impact resistance, and heat resistance.

Description

TECHNICAL FIELD [0001] The present invention relates to a thermoplastic resin composition and a molded article using the thermoplastic resin composition.

A thermoplastic resin composition and a molded article using the same.

Environmental and energy issues fuel economy regulations on the automotive industry is strengthened, were actually strengthened by the EU at 160 g / km emissions of CO ₂ by 2015 to 120 g / km, give the billing and if you exceed it have. In addition, the increase in automotive IT components and the increase in safety / convenience components have resulted in a 30% increase in car-tolerance weight since 1970. In addition, for commercialization of electric vehicles such as EV (Electronic Vehicle) and PHEV (Plug-in Hybrid Electric Vehicle), improvement of fuel efficiency of automobile is an essential factor. Therefore, weight reduction of automobile as a method for solving the above problems is an important issue And research and development are being concentrated. In order to reduce the weight of automobiles, the use of low specific gravity polymer materials is an effective method, and various automobile parts are being replaced with polymer materials and composites. Polymer materials such as ABS and PC / ABS have been developed and applied to automobile interior materials mainly with PP, but automobile structures and the like are limited due to limitations of characteristics.

Polybutylene terephthalate (PBT) is one of the five engineering plastics for automobiles. It has excellent flow properties and is easy to produce large injection molding parts. It has excellent bonding with filler and is a composite material including glass fiber and carbon fiber. Is relatively easy to develop, but the low impact resistance property makes it possible to apply only limited use of PBT. In order to compensate for this, blending with various polymers is a typical butadiene-acrylonitrile-styrene copolymer (ABS). However, since the double bond of the butadiene rubber is easily decomposed by UV and deteriorates at high temperatures, application to automobiles requiring outdoor use and high heat resistance is also limited. Acrylonitrile-styrene-acrylate copolymer (ASA), which is structurally similar to ABS but substituted with butadiene rubber with acrylate rubber, is composed of saturated polymers and is resistant to UV and deterioration and has excellent impact resistance properties and blended with PBT It can offset the shortcomings of PBT and can be used for various automobile applications.

However, since PBT and ASA are not compatible with each other, it is impossible to realize mechanical strength as expected by physical blending. Also, cohesion of dispersed phase due to poor compatibility causes problems of accelerating decomposition of polymer .

To provide a thermoplastic resin composition capable of securing excellent impact resistance and weather resistance and a molded article using the same.

The thermoplastic resin composition according to one embodiment comprises: (A) 50 to 90% by weight of a polybutylene terephthalate resin; And (B) 1 to 10 parts by weight of (C) an ethylene-glycidyl methacrylate graft copolymer based on 100 parts by weight of a base resin containing 10 to 50% by weight of an acrylic graft copolymer.

The molded article according to another embodiment includes the above-mentioned thermoplastic resin composition.

The thermoplastic resin composition according to one embodiment makes it possible to produce a molded article excellent in weather resistance, impact resistance, and heat resistance.

Hereinafter, embodiments of the present invention will be described in detail. In the following description of the present invention, the well-known functions or constructions will not be described in order to clarify the present invention.

According to one embodiment, (A) 50 to 90% by weight of a polybutylene terephthalate resin; (B) 1 to 10 parts by weight of an ethylene-glycidyl methacrylate graft copolymer (C) relative to 100 parts by weight of a base resin containing 10 to 50% by weight of an acrylic graft copolymer Lt; / RTI >

Hereinafter, each component contained in the thermoplastic resin composition will be described in detail.

(A) Polybutylene terephthalate  Suzy

As the polybutylene terephthalate (PBT) resin, polybutylene terephthalate obtained by condensation polymerization of 1,4-butanediol, terephthalic acid or dimethyl terephthalate directly by esterification reaction or transesterification reaction may be used .

In order to increase the impact strength of the resin, the polybutylene terephthalate is mixed with an impact resistance improving component such as polytetramethylene glycol (PTMG), polyethylene glycol (PEG), polypropylene glycol (PPG), aliphatic polyester, aliphatic polyamide, Or a modified polybutylene terephthalate which is a blend blended with the impact resistance improving component may be used.

The polybutylene terephthalate resin may have an intrinsic viscosity [] of 0.36 to 1.60 dl / g as measured according to ASTM D2857. For example, the intrinsic viscosity of the polybutylene terephthalate resin may be from 0.52 to 1.25 dl / g and from 0.70 to 1.00 dl / g.

When the intrinsic viscosity of the polybutylene terephthalate resin is in the above range, it is possible to secure an excellent balance of mechanical properties and moldability and thermal stability of the thermoplastic resin composition.

The polybutylene terephthalate resin may have a specific gravity of 1.0 to 1.5. For example, the specific gravity of the polybutylene terephthalate resin may be 1.1 to 1.4, and may be, for example, 1.25 to 1.35.

The polybutylene terephthalate resin is contained in an amount of 50 to 90% by weight based on the total weight of the base resin including the polybutylene terephthalate resin and the acrylic graft copolymer to be described later. When the polybutylene terephthalate resin is contained in the above range, excellent balance of heat resistance of the molded article using the thermoplastic resin composition and smoothness of the surface of the molded article can be secured.

(B) Acrylic Graft  Copolymer

In the present invention, the acrylic graft copolymer may be a core-shell structure copolymer including a shell layer formed by graft copolymerizing an aromatic vinyl monomer and an unsaturated nitrile monomer to an acrylic rubber-like polymer core. Specifically, the acrylic graft copolymer may include 40 to 60% by weight of an acrylic rubber-like polymer core and 40 to 60% by weight of a shell layer formed by graft copolymerization of an aromatic vinyl monomer and an unsaturated nitrile monomer. The above-mentioned graft copolymerization can be carried out by a usual production method, for example, emulsion polymerization, suspension polymerization, solution polymerization and bulk polymerization.

The acrylic rubber-like polymer core may be composed of an alkyl acrylate rubber, preferably a C2 to C10 alkyl acrylate rubber. As one example, butyl acrylate rubber, ethylhexyl acrylate rubber and mixtures thereof can be used, but not always limited thereto.

The average particle diameter of the acrylic graft copolymer may be 200 to 500 nm, for example, 200 to 400 nm, and 200 to 300 nm.

The average particle size is a value measured by using a photographic image length measured by a transmission electron microscope (TEM), and means an average value of 100 target particles.

The aromatic vinyl monomer and unsaturated nitrile monomer grafted onto the acrylic rubber-like polymer core may be composed of 60 to 80% by weight of an aromatic vinyl monomer and 20 to 40% by weight of an unsaturated nitrile monomer, based on the total weight of the monomers.

Examples of the aromatic vinyl monomer include styrene,? -Methylstyrene, p-methylstyrene, pt-butylstyrene, 2,4-dimethylstyrene, chlorostyrene, vinyltoluene and vinylnaphthalene. These aromatic vinyl monomers may be used alone or in combination . Of these, styrene can be preferably used.

Examples of the unsaturated nitrile monomer include acrylonitrile, methacrylonitrile, and fumaronitrile, which may be used alone or in combination. Of these, acrylonitrile can be preferably used.

The acrylic graft copolymer may preferably be an acrylonitrile-styrene-acrylate graft copolymer (g-ASA).

The g-ASA may be prepared by subjecting an alkyl acrylate rubber to acrylonitrile and styrene to perform graft copolymerization with an alkyl acrylate rubber. In the present invention, the acrylic graft copolymer may be contained in an amount of 10 to 50% by weight based on the total weight of the base resin including the polybutylene terephthalate resin (A) and the acrylic graft copolymer (B). When the content is less than 10% by weight, weather resistance and impact resistance may be deteriorated. If the content is more than 50% by weight, heat resistance may be deteriorated.

(C) Ethylene- Glycidyl methacrylate-based Graft  Copolymer

The ethylene-glycidyl methacrylate graft copolymer (C) is obtained by copolymerizing an ethylene-glycidyl methacrylate copolymer main chain having an ethylene monomer and a glycidyl methacrylate monomer copolymerized with polystyrene, polymethyl methacrylate , Styrene-acrylonitrile copolymer, and the like.

For example, the copolymer grafted to the ethylene-glycidyl methacrylate copolymer backbone may be an aromatic vinyl-unsaturated nitrile copolymer. The aromatic vinyl-unsaturated nitrile copolymer may be a copolymer of an aromatic vinyl monomer and an unsaturated nitrile monomer.

As the aromatic vinyl monomer, at least one selected from styrene, C1 to C10 alkyl-substituted styrene, halogen-substituted styrene, vinyl toluene, vinyl naphthalene, and mixtures thereof may be used. Specific examples of the alkyl-substituted styrene include? -Methylstyrene, p-methylstyrene, o-ethylstyrene, m-ethylstyrene, p-ethylstyrene, pt-butylstyrene and 2,4-dimethylstyrene.

As the unsaturated nitrile monomer, at least one selected from acrylonitrile, methacrylonitrile, fumaronitrile, and mixtures thereof may be used.

The aromatic vinyl-unsaturated nitrile copolymer can be obtained by copolymerizing a copolymer of styrene and acrylonitrile, a copolymer of? -Methylstyrene and acrylonitrile, or a copolymer of styrene,? -Methylstyrene and acrylonitrile And preferably a copolymer of styrene-acrylonitrile. As an example, styrene-acrylonitrile copolymer (SAN) copolymerized with 60 to 75 wt% of styrene and 25 to 40 wt% of acrylonitrile may be used.

For example, the (C) ethylene-glycidyl methacrylate graft copolymer may be an ethylene-glycidyl methacrylate-graft-styrene-acrylonitrile copolymer (EGMA-g-SAN). This may be a copolymer in which a styrene-acrylonitrile copolymer is grafted on an ethylene-glycidyl methacrylate copolymer main chain.

Specifically, the EGMA-g-SAN contains 30 to 70% by weight, based on the total weight of the ethylene-glycidyl methacrylate copolymer, 30 to 70% by weight of the styrene-acrylonitrile copolymer, It may have been broken.

Wherein the ethylene-glycidyl methacrylate graft copolymer (C) is a copolymer of ethylene and 25 to 55% by weight, based on the total weight of the ethylene-glycidyl methacrylate graft copolymer (C) Acrylate copolymer may be prepared by graft copolymerizing 30 to 70% by weight of a styrene-acrylonitrile copolymer with 5 to 15% by weight of the glycidyl methacrylate-copolymerized ethylene-glycidyl methacrylate copolymer have.

On the other hand, the ethylene-glycidyl methacrylate graft copolymer (C) is preferably a graft copolymer having an epoxy functional group of 2 to 10 % By weight. When the content of the epoxy functional group is lower than 2% by weight, the reaction with the polybutylene terephthalate resin is not sufficiently carried out, so that it is difficult to ensure compatibility between the polybutylene terephthalate resin and the acrylic graft copolymer. When the content is higher than 10% The weather resistance of the thermoplastic resin composition may be lowered due to unreacted epoxy functional groups.

The ethylene-glycidyl methacrylate graft copolymer (C) is obtained by copolymerizing 100 parts by weight of a base resin comprising the polybutylene terephthalate resin (A) and the acrylic graft copolymer (B) 1 to 10 parts by weight may be included. When the ethylene-glycidyl methacrylate graft copolymer (C) is out of the above range, the impact resistance and weather resistance of the thermoplastic resin composition may be deteriorated.

The thermoplastic resin composition according to one embodiment of the present invention is intended to improve the mechanical strength and weather resistance as an automotive interior and exterior parts application. The ethylene-glycidyl methacrylate-based graft copolymer (C) ) In the process of mixing the polybutylene terephthalate resin and the acrylic graft copolymer (B), a reactive functional group may serve as a compatibilizer. That is, the ethylene-glycidyl methacrylate graft copolymer (C) is obtained by reducing the interfacial tension between the polybutylene terephthalate resin (A) and the acrylic graft copolymer (B) ) It is possible to improve the impact resistance of the thermoplastic resin composition by improving the dispersibility of the acrylic graft copolymer and improve the compatibility between the components of the thermoplastic resin composition to ensure excellent molding processability.

(D) Other additives

Meanwhile, the thermoplastic resin composition according to one embodiment may further include other additives such as a dye, a pigment, a flame retardant, a filler, an antioxidant, a heat stabilizer, a UV stabilizer, a lubricant, an antibacterial agent and a release agent, Two or more of them may be mixed.

The other additives may be included in the range of 0 to 50 parts by weight based on 100 parts by weight of the base resin comprising the polybutylene terephthalate resin (A) and the acrylic graft copolymer (B).

Hereinafter, the present invention will be described in more detail with reference to examples and comparative examples. However, the following examples and comparative examples are for illustrative purposes only and are not intended to limit the present invention.

Example  1 to Example  6 and Comparative Example  1 to Comparative Example  5

The thermoplastic resin compositions of Examples 1 to 6 and Comparative Examples 1 to 5 were prepared in accordance with the ingredient content ratios described in Table 1 below.

(C) EGMA-g-SAN and (D) SAN-g-GMA added to the base resin are shown in Table 1, in which the constituent elements constituting the base resin are represented by% by weight based on the total weight of the base resin. By weight based on 100 parts by weight of the base resin.

The components shown in Table 1 and other additives were mixed and extruded / processed to prepare a thermoplastic resin composition in the form of a pellet. A twin-screw extruder having an L / D of 29 and a diameter of 45 mm was used for the extrusion, and the barrel temperature was set at 240. The prepared pellets were dried at 80 for 4 hours, and a 6 oz injection molding machine was set at a cylinder temperature of 240 ° C and a mold temperature of 60 ° C to prepare test specimens for evaluation of physical properties.

For each of the Examples and Comparative Examples, 0.2 part by weight of a phosphorus-based antioxidant was added to 100 parts by weight of the base resin to prevent deterioration during extrusion / processing with the other additives, and a montanic wax lubricant 0.5 part by weight was used per 100 parts by weight of the resin.

Example Comparative Example One 2 3 4 5 6 One 2 3 4 5 Polybutylene terephthalate resin
(PBT) (A) 70 70 70 70 90 50 70 70 100 30 70 Acrylonitrile-styrene-acrylate graft copolymer
(g-ASA) (B) 30 30 30 30 10 50 30 30 0 70 30 Ethylene-glycidyl methacrylate-graft-styrene-acrylonitrile copolymer
(EGMA-g-SAN) (C) One 3 5 10 3 3 0 15 3 3 - Styrene-acrylonitrile-graft-glycidyl methacrylate copolymer
(SAN-g-GMA) (D) - - - - - - - - - - 5

The components shown in Table 1 are as follows.

(A) Polybutylene terephthalate resin (PBT)

A polybutylene terephthalate resin having a specific gravity of 1.31 and an intrinsic viscosity of 0.83 dl / g was used. [Manufacturer: Shinkong, Product Name: Shinite K001]

(B) acrylonitrile-styrene-acrylate graft copolymer (g-ASA)

A core-shell structure consisting of 60% by weight of a butyl acrylate rubber core and 40% by weight of a shell, said shell comprising 28% by weight of styrene and 12% by weight of acrylonitrile as styrene-acrylonitrile copolymers An acrylonitrile-styrene-acrylate graft copolymer having an average particle size of about 300 nm was used. [Manufacturer: UMG ABS Ltd., product name: A600N]

(C) Ethylene-glycidyl methacrylate-graft-styrene-acrylonitrile copolymer (EGMA-g-SAN)

A copolymer in which reactive epoxy functional groups were contained in an amount of about 6% by weight based on the weight of the total copolymer and a styrene-acrylonitrile copolymer was grafted on an ethylene-glycidyl methacrylate copolymer main chain was used. [Manufacturer: NOF Corp., product name: A4400]

(D) styrene-acrylonitrile-graft-glycidyl methacrylate copolymer (SAN-g-GMA)

A copolymer in which reactive epoxy functional groups were contained in an amount of about 5 wt% based on the weight of the total copolymer and glycidyl methacrylate was grafted on the styrene-acrylonitrile copolymer main chain was used. [Manufacturer: Fine-blend Compatibilizer Jiangsu Co., Ltd., product name: SAG-005]

Experimental Example

The experimental results are shown in Table 2 below.

(1) Impact resistance (kgf · cm / cm): Notched Izod impact strength was measured at a room temperature on a 1/8 "thick specimen according to ASTM D256.

(2) Weathering resistance: The initial gloss was measured at a reflection angle of 60 ° according to ASTM D523 of a size of 50 mm x 90 mm x 3 mm, and the specimens were exposed for 3,000 hours under the Method A condition of ISO 4892-2 The gloss was measured in the same manner and the gloss retention ratio was calculated according to the following formula (1).

[Formula 1]

Gloss retentivity (%) = (G ₁ / G ₀ ) x 100

(Where G ₀ is the initial gloss of the specimen and G ₁ is the gloss after the specimen is exposed for 3,000 hours under the Method A, ISO 4892-2 standard).

(3) Heat resistance (캜): The Vicat softening temperature (VST) was measured for 1/8 "thick specimens according to ISO 306 / B50.

Example 1 Example 2 Example 3 Example 4 Example 5 Example 6 Comparative Example 1 Comparative Example 2 Comparative Example 3 Comparative Example 4 Comparative Example 5 Izod
Impact strength 10 11 13 15 8 17 5 15 3 15 13 Polish
Retention rate 60 65 70 65 60 85 45 50 30 85 50 VST 105 103 100 90 115 75 108 85 108 50 102

(A) polybutylene terephthalate resin, (B) acryl-based graft copolymer, and (C) ethylene-glycidyl methacrylate-based It is confirmed that the molded article produced from the composition containing the graft copolymer in the content range according to one embodiment has a high gloss retention even after the weatherability evaluation and is excellent in weather resistance and also maintains impact resistance and heat resistance at a certain level or more.

While the present 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 and modifications may be made without departing from the spirit and scope of the following claims. Those skilled in the art will readily understand.

Claims (14)

(A) 50 to 90% by weight of a polybutylene terephthalate resin; And
(B) 100 to 50 parts by weight of a base resin containing 10 to 50% by weight of an acrylic graft copolymer,
(C) 1 to 10 parts by weight of an ethylene-glycidyl methacrylate graft copolymer. The method of claim 1,
The polybutylene terephthalate resin (A) has an intrinsic viscosity of 0.36 to 1.60 dl / g. The method of claim 1,
The acrylic graft copolymer (B)
And a shell layer formed by graft-copolymerizing an aromatic vinyl monomer and an unsaturated nitrile monomer on an acrylic rubber-like polymer core. 4. The method of claim 3,
The acrylic graft copolymer (B), based on the total weight,
40 to 60% by weight of the acrylic rubber-like polymer core and 40 to 60% by weight of a shell layer formed by graft copolymerization of the aromatic vinyl monomer and the unsaturated nitrile monomer. The method of claim 1,
Wherein the (B) acryl-based graft copolymer has an average particle diameter of 200 to 500 nm. The method of claim 1,
Wherein the acryl-based graft copolymer (B) is an acrylonitrile-styrene-acrylate graft copolymer (g-ASA). The method of claim 1,
Wherein the ethylene-glycidyl methacrylate graft copolymer (C) is obtained by grafting an aromatic vinyl-unsaturated nitrile copolymer onto an ethylene-glycidyl methacrylate copolymer main chain. 8. The method of claim 7,
The ethylene-glycidyl methacrylate graft copolymer (C)
Based on the total weight of the (C) ethylene-glycidyl methacrylate graft copolymer,
Wherein 30 to 70% by weight of the aromatic vinyl-unsaturated nitrile copolymer is grafted on the ethylene-glycidyl methacrylate copolymer in an amount of 30 to 70% by weight. 8. The method of claim 7,
The ethylene-glycidyl methacrylate copolymer (C)
Based on the total weight of the (C) ethylene-glycidyl methacrylate graft copolymer,
25 to 55 wt% of the ethylene, and 5 to 15 wt% of the glycidyl methacrylate-copolymerized ethylene-glycidyl methacrylate copolymer are mixed with 30 to 70 wt% of styrene-acrylonitrile copolymer Wherein the thermoplastic resin composition is graft copolymerized. 8. The method of claim 7,
The aromatic vinyl-unsaturated nitrile copolymer is a styrene-acrylonitrile copolymer. 11. The method of claim 10,
The styrene-acrylonitrile copolymer may contain,
60 to 75 wt% of styrene; And
Acrylonitrile and 25 to 40% by weight of acrylonitrile are copolymerized. The method of claim 1,
The ethylene-glycidyl methacrylate graft copolymer (C)
Based on the total weight of the ethylene-glycidyl methacrylate-based graft copolymer (C), 2 to 10% by weight of a reactive functional epoxy group. The method of claim 1,
The thermoplastic resin composition had an Izod impact strength of 6 to 20 kgf · cm / cm in a 1/8 "thick specimen according to ASTM D256,
The bead softening temperature of the 1/8 "thick specimen according to ISO 306 / B50 is 70 to 120 ° C,
The specimens were measured for initial gloss at an angle of reflection of 60 ° according to ASTM D523, and the specimens were exposed for 3,000 hours under the Method A condition of ISO 4892-2, and the gloss was measured in the same manner, And a gloss retention ratio of 55 to 95%.
[Formula 1]
Gloss retentivity (%) = (G ₁ / G ₀ ) x 100
(Where G ₀ is the initial gloss of the specimen and G ₁ is the gloss after the specimen is exposed for 3,000 hours under the Method A, ISO 4892-2 standard). A molded article comprising the thermoplastic resin composition according to any one of claims 1 to 13.