Heat-resistant resin composition and molded article obtained therefrom

Abstract

Embodiments relate to a heat-resistant resin composition having an enhanced heat resistance and a molded article obtained therefrom. The resin composition according to the embodiments has a high heat resistance, so that it is capable of forming an excellent appearance without being deformed even though it is subjected to a process that is carried out at a high temperature of 205° C. or higher, such as an on-line painting. Thus, it can be advantageously used as, for example, an exterior material of various transportation means or a housing of electric and electronic products.

Claims

1. A heat-resistant resin composition, which comprises: a polyphenylene ether (PPE) resin; and a polyamide (PA) resin, wherein the PA resin is a mixed resin of a first PA resin and a second PA resin, wherein a melting point of the first PA resin is higher than a melting point of the second PA resin by 20° C. to 100° C., wherein the first PA resin is a PA 46 resin and the second PA resin is a PA 66 resin, wherein a weight ratio of the PPE resin and the PA resin is 1:0.2 to 8, wherein a weight ratio of the first PA resin and the second PA resin is 1:0.5 to 15, wherein the heat-resistant resin composition has an absorption rate of 1.5% or less at a temperature of 23° C. and a relative humidity of 50% when measured according to ISO 62 standard, and wherein the heat-resistant resin composition has a heat distortion temperature of 205° C. or higher under a low load of 4.6 kgf when measured according to ASTM D648 standard.

2. The heat-resistant resin composition of claim 1, which further comprise an impact modifier that includes a styrene-ethylene-butadiene-styrene (SEBS) resin, a maleic anhydride-grafted styrene-ethylene-butadiene-styrene (MA-SEBS) resin, or a mixture thereof.

3. The heat-resistant resin composition of claim 2, which comprises the impact modifier in an amount of 2% by weight to 25% by weight based on the total weight of the heat-resistant resin composition.

4. The heat-resistant resin composition of claim 1, which further comprise a compatibilizer that includes maleic anhydride, citric acid, or mixtures thereof.

5. The heat-resistant resin composition of claim 1, which further comprises a conductive additive that includes a carbon nanotube, carbon black, a carbon fiber, graphene, a metal powder, or a mixture thereof.

6. A molded article, which is injection molded from the heat-resistant resin composition according to claim 1.

7. The molded article of claim 6, which is a plastic fender for automobiles.

Description

EXAMPLE

(1) Hereinafter, the present invention will be described in detail by referring to Examples. But the following Examples are intended to illustrate the present invention, and the scope of the present invention is not limited thereto only.

(2) PPE resin: PPE, Bluestar

(3) First PA resin: polyamide 46 (melting temperature: 290° C.), Stanyl, DSM

(4) Second PA resin: polyamide 66 (melting temperature: 264° C.), Vydyne, Ascend

(5) Impact modifier: SEBS resin, G1651, Kraton : MA-SEBS resin, FG1901, Kraton

(6) Compatibilizer: maleic anhydride (MA), Yongsan Chemicals

(7) Lubricant: ethylene bis-stearamide (EBS), L-C 140P, Lion Chemtech

(8) Antioxidant: Irganox 1010, BASF

(9) Heat stabilizer: potassium iodide, Nowchem

Examples 1 to 9 and Comparative Examples 1 and 2: Preparation of Resin Compositions

(10) The PPE resin, the first PA resin, and the second PA resin were mixed together with the other components in the amounts shown in Table 1 below to prepare a resin composition. Specifically, the respective components were mixed using a twin-screw extruder of 32 mm under the conditions of 30 kg/hr and 330° C. to prepare a resin composition.

Test Example 1: Heat Deformation Temperature (HDT) Under a Low Load

(11) Each of the resin compositions of Examples 1 to 9 and Comparative Examples 1 and 2 was injection molded using a 170-ton electric injection molding machine at an injection temperature of 300° C. and a mold temperature of 100° C. The specimen having a size of 6.4 mm×128 mm was measured for the thermal deformation temperature under a low load of 4.6 kgf in the edgewise direction according to the ASTM D648 standard.

Test Example 2: Absorption Rate

(12) Each of the resin compositions of Examples 1 to 9 and Comparative Examples 1 and 2 was injection molded in the same manner as in Test Example 1. The specimen having a size of 60 mm×60 mm×2 mm (width, length, and thickness) was measured for the absorption rate at a temperature of 23° C. and a relative humidity of 50% according to the ISO 62 standard.

(13) TABLE-US-00001 TABLE 1 Component (part by weight) First Second MA- Heat Low load Absorption PPE PA PA SEBS SESB stabilizer Compatibilizer Lubricant Antioxidant HDT (° C.) rate (%) Ex. 1 10 40 40 4 6 0.3 0.5 0.3 0.3 219 1.4 Ex. 2 30 30 30 4 6 0.3 0.5 0.3 0.3 211 1.2 Ex. 3 70 10 10 4 6 0.3 0.5 0.3 0.3 206 0.8 Ex. 4 30 5 55 4 6 0.3 0.5 0.3 0.3 207 1.2 Ex. 5 30 40 20 4 6 0.3 0.5 0.3 0.3 213 1.2 Ex. 6 10 80 0 4 6 0.3 0.5 0.3 0.3 234 1.4 Ex. 7 30 60 0 4 6 0.3 0.5 0.3 0.3 225 1.2 Ex. 8 30 20 40 4 6 0.3 0.5 0.3 0.3 216 1.2 Ex. 9 10 5 75 4 6 0.3 0.5 0.3 0.3 206 1.4 C. Ex. 1 0 45 45 4 6 0.3 0.5 0.3 0.3 201 1.8 C. Ex. 2 45 0 45 4 6 0.3 0.5 0.3 0.3 195 1

(14) As shown in Table 1, all of the resin compositions of Examples 1 to 9 had an HDT of 205° C. or higher under a low load and a low absorption rate of 1.5% or less. However, it was confirmed that the resin compositions of Comparative Examples 1 and 2 had lower HDT values than those of the Examples and that the resin composition of Comparative Example 1 had an absorption rate exceeding 1.5%.

(15) From the results shown in Table 1, it is expected that the resin compositions of the Examples are excellent in heat resistance and does not cause deformation even when subjected to a process to be carried out at a high temperature of 205° C. or higher.