KR20150076625A - Polyester Resin Composition - Google Patents

Abstract

The present invention relates to a polyester resin composition, and more specifically, to a polyester resin composition comprising: 100 parts by weight of a basic resin including 20 to 60 wt% of polyethyleneterephthalate (PET) and 40 to 80 wt% of polycarbonate (PC); 5 to 30 parts by weight of a compound including a maleic acid anhydride based on 100 parts by weight of the basic resin; and 3 to 40 parts by weight of barium sulfate. According to the present invention, the polyester resin composition has excellent thermal resistance, impact strength, and band elasticity modulus, has excellent surface polishing properties, and improves low fluidity of a polyethyleneterephthalate-polycarbonate alloy resin, thereby being applied to injection molding for various painting products, and showing mechanical strength, surface polishing properties, and fluidity.

Description

TECHNICAL FIELD [0001] The present invention relates to a polyester resin composition,

The present invention relates to a composition of a material which can be used as an injection-molding material such as a car rear spoiler and crash pads which require gloss and fluidity.

The present invention relates to a polyester resin composition satisfying high impact strength and high flexural modulus at the same time and satisfying the high flowability, and more specifically relates to a polyester resin composition comprising polyethyleneterephthalate resin, polycarbonate resin, impact modifier and barium sulfate Ester compositions.

Parts such as automobile rear spoilers and crash pads are required to be formed of materials such as acrylonitrile butadiene styrene resin and polycarbonate-acrylonitrile butadiene styrene resin because heat resistance, dimensional stability and excellent mechanical properties are required. However, acrylonitrile butadiene styrene resin and polycarbonate-acrylonitrile butadiene styrene resin have low flowability compared to other engineering plastic materials and have a disadvantage that they smell when molded at high temperatures.

In addition, the conventional polyethylene terephthalate-polycarbonate alloy resin has heat resistance and excellent mechanical properties. However, since the viscosity is high, productivity is low when the product is molded. In addition, the unreinforced polyethylene terephthalate-polycarbonate alloy resin has a problem that dimensional stability is not suitable when used as an automobile part. When glass fiber is used as a filler, a synergistic effect of mechanical strength can be obtained, Which is disadvantageous to paintability.

In the case of the conventional polyethylene terephthalate-polycarbonate alloy resin composition, the mechanical properties tend to move depending on the content ratio of polyethylene terephthalate, polycarbonate and impact modifier, so that a composition capable of satisfying the required properties of the parts to be applied It is necessary to develop a composition for introducing a specific additive (filler) which not only has to be developed but also has surface gloss required as parts for automobile painting and satisfies the high fluidity such that productivity can be enhanced.

The present invention aims to provide a polyester resin composition having excellent impact resistance, flexural modulus, gloss and fluidity and a molded article produced therefrom.

Accordingly, the present invention provides, as a first preferred embodiment, 100 parts by weight of a base resin comprising 20 to 60% by weight of polyethylene terephthalate (PET) and 40 to 80% by weight of polycarbonate (PC) 5 to 30 parts by weight of a compound containing maleic anhydride relative to 100 parts by weight of the base resin; And 3 to 40 parts by weight of barium sulfate.

The polyester resin composition according to the embodiment may further include 100 parts by weight of a base resin containing 20 to 60% by weight of polyethylene terephthalate (PET) and 40 to 80% by weight of polycarbonate (PC); 5 to 20 parts by weight of a compound containing maleic anhydride relative to 100 parts by weight of the base resin; And 3 to 30 parts by weight of barium sulfate.

The polyethylene terephthalate resin according to the embodiment may have an intrinsic viscosity of 0.5 to 1.2 dl / g, and a polycarbonate resin may have a viscosity average molecular weight (Mv) of 15,000 to 35,000.

The compound containing maleic anhydride according to this embodiment may be represented by the following formula (1).

The barium sulfate according to this embodiment may be a white powder having a specific gravity of 3.5 to 4.5, a refractive index of 1.5 to 2.0, a purity of 90 to 99%, and a diameter of 0.1 to 200 탆.

The polyester resin composition according to this embodiment may further comprise at least one additive selected from the group consisting of a heat stabilizer, a release agent and an antioxidant.

The present invention also provides, as a second preferred embodiment, a molded article produced from the polyester resin composition.

The polyester resin composition according to the present invention has excellent impact resistance, flexural modulus and high fluidity, and can be used particularly as an injection-molding material for automobile rear spoilers and crash pads.

1 is a photograph showing the surface of a specimen made of a polyester resin composition produced according to an embodiment (Example 1) of the present invention.
2 is a photograph showing the surface of a specimen made of a polyester resin composition produced according to Comparative Example (Comparative Example 6) of the present invention.
Fig. 3 is a photograph showing the surface of a specimen made of the polyester resin composition produced according to another comparative example (Comparative Example 7) of the present invention. Fig.
4 is a photograph showing the surface of a specimen made of the polyester resin composition prepared according to Comparative Example 8 of the present invention (Comparative Example 8).

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

The present invention relates to a resin composition comprising 100 parts by weight of a base resin comprising 20 to 60% by weight of a polyethylene terephthalate resin (PET) and 40 to 80% by weight of a polycarbonate resin (PC) 5 to 30 parts by weight of a compound containing maleic anhydride relative to 100 parts by weight of the base resin; And 3 to 40 parts by weight of barium sulfate.

The present invention also relates to a resin composition comprising 100 parts by weight of a base resin comprising 20 to 60% by weight of a polyethylene terephthalate (PET) resin and 40 to 80% by weight of a polycarbonate (PC) 5 to 20 parts by weight of a compound containing maleic anhydride relative to 100 parts by weight of the base resin; And 3 to 30 parts by weight of barium sulfate.

[Basic Resin]

The base resin according to the present invention may comprise 20 to 60% by weight of polyethylene terephthalate (PET) and 40 to 80% by weight of polycarbonate (PC).

The base resin according to the present invention comprises 20 to 60% by weight of a polyethylene terephthalate (PET) resin having an intrinsic viscosity of 0.5 to 1.2 dl / g and a polycarbonate (PC) resin having a viscosity average molecular weight (Mv) of 15,000 to 35,000 % ≪ / RTI > by weight.

In this case, the intrinsic viscosity (?) Can be measured at 20 占 폚 using a Ureter-type viscosity tube after the sample to be measured is dissolved in methylene chloride.

Polyethylene terephthalate  (PET) resin

The polyethylene terephthalate (PET) resin is produced by condensation polymerization through direct esterification reaction or transesterification reaction using ethylene glycol, terephthalic acid or dimethyl terephthalate as monomer, and its intrinsic viscosity is 0.5-1.2 dl / g have. When the intrinsic viscosity of the PET resin is less than 0.5, the overall mechanical properties of the resin composition may be deteriorated. When the intrinsic viscosity is more than 1.2, processing due to the decrease in flowability during injection molding may be difficult due to high viscosity.

In the present invention, the content of the PET resin may be 20 to 60% by weight in the base resin. If the content of the PET resin is less than 20% by weight, the effect of improving the flexural modulus may be insignificant. There may be a limit.

Polycarbonate  (PC) resin

The polycarbonate (PC) resin may be an aromatic polycarbonate resin produced by the interfacial polycondensation reaction of bisphenol A and phosgene, and may have a viscosity average molecular weight (Mv) of 15,000 to 35,000. The viscosity average molecular weight If it is less than 15,000, the impact strength may be lowered, and if it is more than 35,000, the flowability may be lowered.

In the present invention, the content of the PC resin may be 40 to 80% by weight in the base resin, and if the content of the PC resin is less than 40% by weight, the effect of improving impact properties may be insignificant. If the content of PC resin is less than 80% .

The viscosity average molecular weight was determined by dissolving the polycarbonate pellet in methylene chloride and measuring the intrinsic viscosity [?] Of the resultant filtrate at 20 ° C using a Ubero type viscometer and then measuring the intrinsic viscosity [?] Can be calculated using equation

[?] = 1.23 X 10 ^ (-5) X Mv ^ (0.83)

[Compound containing maleic anhydride (impact reinforcement)]

The compound containing maleic anhydride according to the present invention plays a role of an impact-proofing agent and has excellent properties of compatibility with a polyester resin. Specifically, in the present invention, the compound containing maleic anhydride has good compatibility with PET resin and PC, and can contribute to the PET and PC alloy.

In addition, the compound containing maleic anhydride may improve the viscosity of the polyester resin composition to give a viscosity for the basic extrusion molding property of the polyester resin composition, thereby improving the continuous deflection phenomenon of the extrudate during extrusion molding In addition, the impact strength of the polyester resin composition can be reinforced.

The content of the maleic anhydride-containing compound may be 5 to 30 parts by weight based on 100 parts by weight of the polyester resin. If the content of the maleic anhydride is less than 5 parts by weight, the mechanical strength may not be improved. The content of the compound containing maleic anhydride is preferably 5 to 20 parts by weight based on 100 parts by weight of the polyester resin from the viewpoint of economy.

The compound containing maleic anhydride can be selected in consideration of the reactivity with the polyester terminal group, the compatibility with the polyester resin, and the viscosity characteristic suitable for the extrusion moldability, and the compound containing maleic anhydride is represented by the following formula . ≪ / RTI >

[Chemical Formula 1]

Here, m, n and p are integers of 10 to 50, respectively.

More specifically, the compound containing maleic anhydride may be a copolymer in which a maleic anhydride functional group is grafted on polyethylene octene.

[Barium sulfate (inorganic filler)]

The barium sulfate of the present invention can serve as an inorganic filler to improve the flowability and stiffness of the base resin of the polyethylene terephthalate resin and the polycarbonate resin. The content of the barium sulfate is 3 To 30 parts by weight, and if the content is less than 3 parts by weight, the effect of improving the flowability may be insignificant. The content of barium sulphate is preferably 3 to 30 parts by weight based on 100 parts by weight of the polyester resin from the viewpoint of economy.

The barium sulfate may be a white powder having a specific gravity of 3.5 to 4.5, a refractive index of 1.5 to 2.0, a purity of 90 to 99% and a diameter of 0.1 to 200 탆, and the specific gravity, refractive index, purity, Outside the range, improvement of mechanical strength and improvement of surface smoothness as filler may be insignificant.

The polyester resin composition of the present invention may further contain additives according to required characteristics, and the additives may be at least one selected from the group consisting of heat stabilizers, mold release agents and antioxidants.

The antioxidant may be selected from phenol type, phosphite type, thioether type and amine type.

The release agent may be selected from a fluorine-containing polymer, a silicone oil, a metal stearate, a montanic acid metal salt, a montanic ester wax, and a polyethylene wax.

The polyester resin composition according to the present invention may include a base resin comprising a polyethylene terephthalate resin and a polycarbonate resin, a compound containing maleic anhydride, and barium sulfate. Specifically, the polyester resin composition preferably has an impact strength of 65 to 80 J / m (ASTM 256, 2.75 J) and a flexural modulus of 21,000 to 23,500 kgf / cm2 (ASTM 790) and a melt index value of 20 to 35 g / 10 min (ASTM D1238, 270 DEG C / 2.16 kg). The polyester resin composition according to the present invention exhibiting such physical properties can be applied to painted automobile parts such as a car rear spoiler and a crash pad.

BEST MODE FOR CARRYING OUT THE INVENTION Hereinafter, the constitution and effects of the present invention will be described in more detail with reference to specific examples and comparative examples in order to facilitate understanding of the invention. However, the following examples are for the purpose of making the invention more clearly understood, and the invention is not limited to the following examples.

Example 1

(Manufactured by Dupont) and barium sulfate (manufactured by Gemme) containing PET resin (manufactured by Kolon) and PC resin (manufactured by Sabic Co., Ltd.), 245 to 270 The polyester resin composition was prepared in the form of a chip after being melted and kneaded in a twin-screw extruder heated to 120 ° C, and dried using a dehumidifying dryer at 120 ° C for 5 hours.

Examples 2, 3 and 4

A polyester resin composition was prepared in the same manner as in Example 1, except that the content of the compound containing maleic anhydride was changed as shown in Table 1.

Examples 5, 6 and 7

A polyester resin composition was prepared in the same manner as in Example 1, except that the content of barium sulfate was changed as shown in Table 1.

Examples 8 and 9

A polyester resin composition was prepared in the same manner as in Example 1, except that the content of the PET resin and the PC resin was changed as shown in Table 1.

Comparative Example 1

A polyester resin composition was prepared in the same manner as in Example 1, except that barium sulfate was not used.

Comparative Example 2

A polyester resin composition was prepared in the same manner as in Example 1, except that the content of the compound containing maleic anhydride was changed as shown in Table 1.

Comparative Example 3

A polyester resin composition was prepared in the same manner as in Example 1, except that the content of barium sulfate was changed as shown in Table 1.

Comparative Example 4 and Comparative Example 5

A polyester resin composition was prepared in the same manner as in Example 1, except that the content of the PET resin and the PC resin was changed as shown in Table 1.

Comparative Example 6

A polyester resin composition was prepared in the same manner as in Example 1, except that glass fiber (manufactured by KCC) was used instead of barium sulfate.

Comparative Example 7

A polyester resin composition was prepared in the same manner as in Example 1 except that tin (instead of barium sulfate) (manufactured by KOCH) was used.

Comparative Example 8

A polyester resin composition was prepared in the same manner as in Example 1, except that whisker (manufactured by NP) was used instead of barium sulfate.

The polyester resin compositions prepared in Examples and Comparative Examples were each prepared at the same temperature as that in melting and kneading using a heated screw extruder to evaluate the physical properties thereof.

Specifically, tensile strength, flexural strength, flexural MD, impact strength, and melt index were evaluated by using the specimens produced using the polyester resin compositions prepared in Examples and Comparative Examples as follows, Are shown in Table 2.

1. Tensile strength: A 1/8-inch specimen was prepared in accordance with ASTM D638 and the tensile strength measurement rate was set at 50 mm / min.

2. Flexural strength: A 1/8 inch specimen was prepared in accordance with ASTM D790, and the flexural strength measurement speed was set at 10 mm / min.

3. Flexural modulus (MD, modulus): A 1/8-inch specimen was prepared according to ASTM D790, and the flexural modulus measurement rate was set at 10 mm / min.

4. Impact strength: A 1/4-inch specimen was prepared according to ASTM D256 and the Izod Notched impact strength was measured at room temperature (23 ° C).

5. Melt Index (MI): Measured under a load of 2.16 kg at 270 DEG C according to ASTM D1238.

division Base resin (100 parts by weight) The compound containing maleic anhydride (parts by weight) Barium sulfate (parts by weight) Glass fiber (parts by weight) Pyrophyllite (parts by weight) Whiskers (parts by weight) PET (% by weight) PC (% by weight) Example 1 30 70 10 10 0 0 0 Example 2 30 70 5 10 0 0 0 Example 3 30 70 20 10 0 0 0 Example 4 30 70 22 10 0 0 0 Example 5 30 70 10 3 0 0 0 Example 6 30 70 10 30 0 0 0 Example 7 30 70 10 32 0 0 0 Example 8 20 80 10 10 0 0 0 Example 9 60 40 10 10 0 0 0 Comparative Example 1 30 70 10 0 0 0 0 Comparative Example 2 30 70 3 10 0 0 0 Comparative Example 3 30 70 10 One 0 0 0 Comparative Example 4 15 85 10 10 0 0 0 Comparative Example 5 65 35 10 10 0 0 0 Comparative Example 6 30 70 10 0 10 0 0 Comparative Example 7 30 70 10 0 0 10 0 Comparative Example 8 30 70 10 0 0 0 10

division The tensile strength Flexural strength Flexion MD Impact strength MI unit Kgf / ㎠ Kgf / ㎠ Kgf / ㎠ J / m g / 10 min Example 1 490 775  22,200 70 32 Example 2 480 760  23,500 65 27 Example 3 500 770  22,700 73 30 Example 4 500 770  22,500 74 31 Example 5 480 760  21,600 75 23 Example 6 485 775  23,400 65 33 Example 7 510 780  22,000 70 35 Example 8 500 775  22,000 77 27 Example 9 460 780  22,500 65 35 Comparative Example 1 515 790  21,600 76 19 Comparative Example 2 450 705  20,000 14 30 Comparative Example 3 515 790  21,000 70 18 Comparative Example 4 500 770  20,000 90 12 Comparative Example 5 450 800  23,000 44 40 Comparative Example 6 745 1300  41,500 75 16 Comparative Example 7 470 750  20,900 42 43 Comparative Example 8 470 600  14,100 41 79

As a result of measurement of physical properties, as shown in Table 2,

When barium sulfate is not used as in Comparative Example 1, the melt index is lowered and the fluidity is not good.

Further, as described in Comparative Example 2, when the amount of the compound containing maleic anhydride was less than the proper amount, the tensile strength, flexural strength and impact strength were found to be lowered.

In addition, as described in Comparative Example 3, when the barium sulfate content was less than the proper amount, the melt index was found to be lowered.

In addition, as described in Comparative Example 4, when the PET contained in the base resin is less than the proper amount and the PC exceeds the proper amount, the melt index is lowered.

In addition, as described in Comparative Example 5, when the PET contained in the base resin exceeded the proper amount and the PC was below the proper amount, the tensile strength and the impact strength were lowered.

Further, as described in Comparative Example 6, when glass fiber was used in place of barium sulfate, the melt index was found to be lowered.

In addition, as described in Comparative Example 7, when pyrophosphate was used instead of barium sulfate, the impact strength was found to increase more than necessary.

In addition, as described in Comparative Example 8, when whiskers were used instead of barium sulfate, the flexural strength, flexural MD and impact strength were lowered.

In the case of the polyester resin compositions prepared in Examples 1 to 9, the measured physical properties were generally excellent, and when barium sulfate was used as compared with other fillers, the mechanical strength of the base resin including PET resin and PC resin And the effect of giving flexibility is large.

Further, barium sulfate, glass fiber, pyrophyllite and whistler were used as fillers in Example 1 (FIG. 1), Comparative Example 8 (FIG. 2), Comparative Example 9 (FIG. 3) and Comparative Example 10 A disk specimen having a thickness of 3 mm was produced using the produced polyester resin composition, and the surfaces of the specimens were as shown in Figs. 1 to 4, respectively.

As shown in Figs. 1 to 4, when barium sulfate is used as the filler, it is possible to visually confirm that the surface gloss (surface cleanliness) is superior to other fillers, and that barium sulfate can be used as a filler, It can be seen that the ester resin composition is applicable not only to mechanical strength and flexibility but also to a field requiring glossiness.

While the present invention has been particularly shown and described with reference to specific embodiments thereof, those skilled in the art will appreciate that such specific embodiments are merely preferred embodiments and that the scope of the present invention is not limited thereto will be. Accordingly, the actual scope of the present invention will be defined by the appended claims and their equivalents.

Claims (7)

100 parts by weight of a base resin comprising 20 to 60% by weight of polyethylene terephthalate (PET) and 40 to 80% by weight of polycarbonate (PC);
5 to 30 parts by weight of a compound containing maleic anhydride relative to 100 parts by weight of the base resin; And
And 3 to 40 parts by weight of barium sulfate. The method according to claim 1,
100 parts by weight of a base resin comprising 20 to 60% by weight of polyethylene terephthalate (PET) and 40 to 80% by weight of polycarbonate (PC);
5 to 20 parts by weight of a compound containing maleic anhydride relative to 100 parts by weight of the base resin; And
And 3 to 30 parts by weight of barium sulfate. The method according to claim 1,
The polyethylene terephthalate resin has an intrinsic viscosity of 0.5 to 1.2 dl / g,
Wherein the polycarbonate resin has a viscosity average molecular weight (Mv) of 15,000 to 35,000. The method according to claim 1,
Wherein the maleic anhydride-containing compound is represented by the following formula (1).
[Chemical Formula 1]

Here, m, n and p are integers of 10 to 50, respectively. The method according to claim 1,
Wherein the barium sulfate is a white powder having a specific gravity of 3.5 to 4.5, a refractive index of 1.5 to 2.0, a purity of 90 to 99%, and a diameter of 0.1 to 200 占 퐉. The method according to claim 1,
Wherein the polyester resin composition further comprises at least one additive selected from the group consisting of a heat stabilizer, a release agent, and an antioxidant. A molded article produced from the polyester resin composition according to any one of claims 1 to 6.

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