KR101958576B1 - Polyamide resin composition and article comprising the same - Google Patents

Abstract

A polyamide resin composition of the present invention comprises: 35 to 45 wt% of an aromatic polyamide resin comprising a repeating unit represented by chemical formula 1, a repeating unit represented by chemical formula 2, and a repeating unit represented by chemical formula 3; 10 to 15 wt% of an aliphatic polyamide resin; 10 to 20 wt% of a phosphinic acid metal salt; and 30 to 40 wt% of glass fibers. The polyamide resin composition has excellent flame retardancy, long-term heat stability, withstand voltage characteristics and the like.

Description

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

The present invention relates to a polyamide resin composition and a molded article containing the same. More specifically, the present invention relates to a polyamide resin composition excellent in flame retardance, long-term heat resistance stability, and withstand voltage characteristics, and a molded article comprising the same.

BACKGROUND ART Polyamide resins such as polyphthalamide resins are excellent in heat resistance, abrasion resistance, chemical resistance and moldability and are used in a wide range of fields such as electric parts, electronic parts and automobile parts.

However, such a polyamide resin has lower long-term heat stability and flame retardancy than polyphenylene sulfide resin having self-extinguishing properties, and it is difficult to completely replace polyphenylene sulfide resin or the like. In addition, a metal salt stabilizer and a flame retardant may be added to improve the long-term heat stability and flame retardancy of the polyamide resin. However, when they are used in excess, degradation of the resin and mechanical properties such as oxidation of the metal salt- , Heat resistance, and electrical characteristics may be deteriorated, which is not suitable for use in high-voltage parts applications.

Therefore, there is a need to develop a polyamide resin composition excellent in flame retardance, long-term heat stability, withstand voltage characteristics and balance of physical properties without such problems.

The background art of the present invention is disclosed in Korean Patent Publication No. 10-2015-0013674.

An object of the present invention is to provide a polyamide resin composition excellent in flame retardance, long-term heat stability, and withstand voltage characteristics.

Another object of the present invention is to provide a molded article formed from the polyamide resin 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 relates to a polyamide resin composition. The polyamide resin composition comprises 35 to 45% by weight of an aromatic polyamide resin comprising a repeating unit represented by the following formula (1), a repeating unit represented by the following formula (2) and a repeating unit represented by the following formula (3); 10 to 15% by weight of an aliphatic polyamide resin; 10 to 20% by weight of phosphinic acid metal salt; And 30 to 40% by weight of glass fibers;

[Chemical Formula 1]

(2)

(3)

In the general formulas (1) and (2), R ₁ and R ₂ are each independently a hydrocarbon group having 1 to 6 carbon atoms or a halogen atom, and n ₁ and n ₂ are each independently an integer of 0 to 4.

In an embodiment, the aromatic polyamide resin is a mixture of 55 to 75% by weight of the repeating unit represented by Formula 1, 20 to 30% by weight of the repeating unit represented by Formula 2, and 5 to 15% by weight of the repeating unit represented by Formula 3 %. ≪ / RTI >

In an embodiment, the aromatic polyamide resin may have a terminal carboxyl group concentration of 30 to 70 μeq / g and a terminal amine group concentration of 180 to 260 μeq / g.

In an embodiment, the aromatic polyamide resin may have an end carboxyl group and a terminal amine group in a concentration ratio of 1: 3.5 to 1: 7.5.

In an embodiment, the aliphatic polyamide resin may comprise at least one of polyamide 6, polyamide 11, polyamide 12, polyamide 46, polyamide 66, and polyamide 610.

In an embodiment, the weight ratio of the aromatic polyamide resin and the aliphatic polyamide resin may be from 1: 0.2 to 1: 0.45.

In an embodiment, the polyamide resin composition may further include a flame retardant adjuvant.

In an embodiment, the polyamide resin composition may have a flame retardancy of 0.8 mm or more and a thickness of 1.5 mm, measured by UL-94 vertical test method, of V-0 or higher, respectively.

In a specific example, the polyamide resin composition may have a tensile strength retention ratio of 85% or more according to the following formula 1:

[Formula 1]

Tensile strength retention (%) = TS ₁ / TS ₀ 100

TS ₀ is the initial tensile strength of the 3.2 mm thick specimen measured in accordance with ASTM D638 and TS ₁ is the tensile strength measured according to ASTM D638 after holding the specimen in an oven at 200 ° C for 500 hours, to be.

In an embodiment, the polyamide resin composition may have a dielectric breakdown strength of 20 to 30 kV / mm for a 1 mm thick specimen measured according to ASTM D149.

Another aspect of the present invention relates to a molded article. The molded article is formed from the polyamide resin composition.

INDUSTRIAL APPLICABILITY The present invention has a polyamide resin composition excellent in flame retardance, long-term heat stability, and withstand voltage characteristics and the effect of the present invention which provides a molded article formed from the composition.

Hereinafter, the present invention will be described in detail.

The polyamide resin composition according to the present invention comprises (A) an aromatic polyamide resin; (B) an aliphatic polyamide resin; (C) phosphinic acid metal salt; And (D) glass fibers.

(A) an aromatic polyamide resin

The aromatic polyamide resin of the present invention contains three different dicarboxylic acid units and is applied together with the remaining components to provide a polyamide resin composition having an electric voltage resistance characteristic, a long-term heat resistance stability, a flame retardancy, a heat resistance, And so on. The aromatic polyamide resin includes a repeating unit represented by the following formula (1), a repeating unit represented by the following formula (2), and a repeating unit represented by the following formula (3).

[Chemical Formula 1]

(2)

(3)

In the general formulas (1) and (2), R ₁ and R ₂ are each independently a hydrocarbon group having 1 to 6 carbon atoms or a halogen atom, and n ₁ and n ₂ are each independently an integer of 0 to 4.

In an embodiment, the aromatic polyamide resin is terephthalic acid or an alkyl ester thereof substituted or unsubstituted with a phenyl group as R < ₁ >; Terephthalic acid or an alkyl ester thereof substituted or unsubstituted with a phenyl group as R ₂ ; Adipic acid or alkyl esters thereof; And 1,6-hexanediamine according to a known polymerization method.

In the specific examples, the repeating unit represented by the formula (1) may be contained in an amount of 55 to 75 mol%, for example, 60 to 70 mol% in 100 mol% of the aromatic polyamide resin, 20 to 30 mol%, for example, 22 to 28 mol% in 100 mol% of the polyamide resin, and the repeating unit represented by the above formula (3) may be contained in an amount of 5 to 15 mol% For example, 8 to 12 mol%. Within the above range, the polyamide resin composition can have excellent withstand voltage characteristics, long-term heat resistance stability, flame retardancy and the like.

In an embodiment, the aromatic polyamide resin may have a terminal carboxyl group concentration of 30 to 70 μeq / g, for example, 45 to 55 μeq / g, as measured by a titrimetric method, and the concentration of the terminal amine group measured by the titrimetric method is 180 To 260 μeq / g, for example, 190 to 245 μeq / g. Within the above range, the heat resistance (long-term heat stability) and rigidity of the polyamide resin composition can be excellent.

In embodiments, the aromatic polyamide resin may have a concentration ratio of the terminal carboxyl groups and terminal amine groups of 1: 3.5 to 1: 7.5, such as 1: 3.5 to 1: 5.5. Within the above range, the heat resistance (long-term heat stability) and rigidity of the polyamide resin composition may be more excellent.

In an embodiment, the aromatic polyamide resin is dissolved in a concentrated sulfuric acid solution (98%) at a concentration of 0.5 g / dL, and then an intrinsic viscosity [?] Measured by a Ubbelohde viscometer at 25 ° C is 0.75 to 0.95 dL / g, for example 0.85 to 0.95 dL / g. Within the above range, the processability and heat resistance of the polyamide resin composition can be excellent.

In an embodiment, the aromatic polyamide resin may include 35 to 45 wt%, for example, 37 to 42 wt% of 100 wt% of the total polyamide resin composition. If the content of the aromatic polyamide resin is less than 35% by weight, the flame retardancy, long-term heat resistance, withstand voltage characteristics, rigidity and the like of the polyamide resin composition may deteriorate. When the content exceeds 45% by weight, , Workability, impact resistance, and the like may be lowered.

(B) an aliphatic polyamide resin

The aliphatic polyamide resin according to one embodiment of the present invention can improve the withstand voltage characteristics, the long-term heat stability, the flame retardance, the impact resistance, the workability, etc. of the polyamide resin composition together with the aromatic polyamide resin, Amide resin can be used.

In an embodiment, the aliphatic polyamide resin may include polyamide 6, polyamide 11, polyamide 12, polyamide 46, polyamide 66, and polyamide 610, combinations thereof, and the like.

In an embodiment, the aliphatic polyamide resin is dissolved in a concentrated sulfuric acid solution (96%) at a concentration of 0.5 g / dL and then the relative viscosity [η _rel ] measured by a Ubbelohde viscometer at 25 ° C is 2 to 3 , For example, from 2.3 to 2.8. Within the above range, the processability and impact resistance of the polyamide resin composition can be excellent.

In an embodiment, the aliphatic polyamide resin may comprise 10 to 15% by weight, for example 11 to 14% by weight, of 100% by weight of the total polyamide resin composition. When the content of the aliphatic polyamide resin is less than 10% by weight, the flame retardancy, long-term heat stability, appearance and impact resistance of the polyamide resin composition may be deteriorated. When the content is more than 15% by weight, , Withstand voltage characteristics, heat resistance, rigidity, and the like may be lowered.

In an embodiment, the weight ratio of the aromatic polyamide resin and the aliphatic polyamide resin may be from 1: 0.2 to 1: 0.45, for example from 1: 0.3 to 1: 0.4. In the above range, the flame retardancy, long-term heat stability, and withstand voltage characteristics of the polyamide resin composition can be more excellent.

(C) Phosphinic acid metal salt

The phosphinic acid metal salt according to one embodiment of the present invention is capable of improving the flame retardancy and processability without deteriorating the long-term heat stability and withstand voltage characteristics of the polyamide resin composition. For example, phosphinic acid metal salt of phosphinic acid A salt and / or a diphosphinic acid salt represented by the following formula (5), and the like.

[Chemical Formula 4]

[Chemical Formula 5]

Wherein R ₃ and R ₄ are each independently an alkyl group having 1 to 6 carbon atoms or an aryl group having 6 to 10 carbon atoms and R ₅ is an alkylene group having 1 to 10 carbon atoms or an arylene group having 6 to 10 carbon atoms M is at least one element selected from the group consisting of Mg, Ca, Zn, Al, Sb, Sn, Ge, Ti, Fe, Zr, Ce, Bi, Sr, Mn, Li, B is an integer of 1 to 4, and x is an integer of 1 to 4,

The M may be, for example, zinc (Zn), aluminum (Al), titanium (Ti), zirconium (Zr), iron (Fe)

In an embodiment, the phosphinic acid metal salt may have an average particle size of 0.2 to 50 mu m, for example, 0.5 to 40 mu m, specifically 1 to 10 mu m. Within the above range, the flame retardancy, fluidity, appearance and the like of the polyamide resin composition can be excellent.

In the present invention, unless otherwise stated, the average particle diameter is a number average diameter, and means D50 (particle diameter at a point where the distribution ratio is 50%) is measured by an electron microscope or the like.

In an embodiment, the phosphinate acid metal salt may be contained in an amount of 10 to 20% by weight, for example, 12 to 18% by weight, based on 100% by weight of the total polyamide resin composition. When the content of the phosphinic acid metal salt is less than 10% by weight, the flame retardancy and the like of the polyamide resin composition may deteriorate. When the content is more than 20% by weight, the long-term heat stability and the withstand voltage characteristics may be deteriorated.

(D) glass fiber

The glass fiber according to one embodiment of the present invention can improve the rigidity, impact resistance, heat resistance, and the like of the polyamide resin composition, and glass fibers used in ordinary thermoplastic resin compositions can be used.

In an embodiment, the glass fiber may have various shapes such as a fiber shape, a particle shape, a rod shape, an acicular shape, a flake shape, and an amorphous shape, and may have various shapes such as a circle, an ellipse, and a rectangle. For example, it may be preferable from the viewpoint of mechanical properties to use a fibrous glass fiber having a circular and / or rectangular cross section.

In a specific example, the glass fiber of the circular cross section may have a cross-sectional diameter of 5 to 20 탆 and a length before shaping of 2 to 20 mm, the glass fiber of the rectangular cross-section has an aspect ratio of 1.5 to 10, May be between 2 and 20 mm. Within the above range, the rigidity, workability and the like of the polyamide resin composition can be improved.

In an embodiment, the glass fibers may comprise 30 to 40 wt%, for example 32 to 38 wt%, of 100 wt% of the total polyamide resin composition. Within the above range, the polyamide resin composition may have excellent rigidity, impact resistance, heat resistance, and the like.

The polyamide resin composition according to one embodiment of the present invention may further contain conventional additives as necessary insofar as the effect of the present invention is not impaired. The additives include, but are not limited to, a flame retardant aid, an antioxidant, a lubricant, a release agent, a nucleating agent, an antistatic agent, a stabilizer, a colorant,

In an embodiment, the flame retardant aid is selected from the group consisting of silicon, metal oxides (e.g., silica, boehmite, aluminum oxide, iron oxide, titanium oxide, manganese oxide, magnesium oxide, zirconium oxide, (For example, aluminum, iron, titanium, manganese, zinc, molybdenum, cobalt, bismuth, chrome, tin, and the like), metal oxides such as cobalt, bismuth oxide, chromium oxide, tin oxide, antimony oxide, (For example, barium metaborate, zinc carbonate, magnesium carbonate, calcium carbonate, and barium carbonate), and the like can be given as examples of the antimony, nickel, copper, and tungsten. For example, boehmite (aluminum hydroxide oxide (AlO (OH))), aluminum oxide and the like can be used.

In an embodiment, when the additive is used, the content thereof may be 20 wt% or less in 100 wt% of the total polyamide resin composition.

The polyamide resin composition according to one embodiment of the present invention may be in the form of a pellet obtained by melt-extruding at 200 to 350 ° C, for example, 250 to 300 ° C using a conventional twin-screw extruder by mixing the above components.

In an embodiment, the polyamide resin composition may have a flame retardancy of 0.8 mm or more and a thickness of 1.5 mm, measured by UL-94 vertical test method, of V-0 or higher, respectively.

In an embodiment, the polyamide resin composition may have a tensile strength retention ratio of 85% or more, for example, 89 to 100% according to the following formula 1:

[Formula 1]

Tensile strength retention (%) = TS ₁ / TS ₀ 100

TS ₀ is the initial tensile strength of the 3.2 mm thick specimen measured in accordance with ASTM D638 and TS ₁ is the tensile strength measured according to ASTM D638 after holding the specimen in an oven at 200 ° C for 500 hours, to be.

In an embodiment, the polyamide resin composition may have a dielectric breakdown strength of 20 to 30 kV / mm, for example, 23 to 28 kV / mm, as measured according to ASTM D149.

The molded article according to the present invention is formed from the polyamide resin composition. For example, the polyamide resin composition can be used to produce a molded article by a known molding method such as injection molding, double injection molding, blow molding, extrusion molding, and thermoforming. The molded article can be easily formed by a person having ordinary skill in the art to which the present invention belongs.

In an embodiment, the molded article can be applied to various fields to which the polyamide resin composition is applied. Since the molded product is excellent in flame retardancy, long-term heat stability, dielectric strength, and balance of physical properties, it can be particularly useful for high voltage parts and the like requiring such properties.

Hereinafter, the present invention will be described in more detail by way of examples, but these examples are for illustrative purposes only and should not be construed as limiting the present invention.

Example

The specifications of each component used in the following examples and comparative examples are as follows.

(A) an aromatic polyamide resin

(A1) Polyamide 6T / 6I / 66 (manufactured by Evonik Industries, product name: M1100, 6T: 6I: 66 (molar ratio) = 66:24:10, intrinsic viscosity [?]: 0.85 dL / g, terminal carboxyl group concentration: 50 μeq / g, terminal amine group concentration: 215 μeq / g) was used.

(A2) A polyamide 6T / 66 (manufactured by Solvay, product name: A6000, 6T: 66 (molar ratio) = 55:44, intrinsic viscosity [?]: 0.95 dL / g, terminal carboxyl group concentration: 46 μeq / g, Concentration: 100 μeq / g) was used.

(B) an aliphatic polyamide resin

Polyamide 6 (manufacturer: KP Chemtech, product name: EN-300, relative viscosity [? _Rel ]: 2.5) was used.

(C) Flame retardant

(C1) phosphinic acid aluminum salt (manufacturer: Clariant, product name: OP-1240) was used as the phosphinic acid metal salt.

(C2) triphenylphosphate (manufacturer: Daihachi Chemical Industry, product name: TPP) was used.

(D) glass fiber

Glass fiber (manufacturer: Nippon Electric Glass, product name: ECS-30T-717H) was used.

(E) Flame Retarding Agent

Boehmite (manufacturer: Nabaltec, product name: AOH 60) was used.

Examples 1 to 8 and Comparative Examples 1 to 8

The above components were mixed according to the compositions and contents of Tables 1 and 2, and then the mixture was fed into a twin screw type extruder having L / D = 40 and a diameter of 48 mm, and melted and extruded at a barrel temperature of 300 ° C. To prepare pellets. The prepared pellets were dehumidified and dried at 100 ° C. for 6 to 8 hours, and then injection molded at a cylinder temperature of 320 ° C. and a mold temperature of 80 ° C. to prepare specimens. The properties of the prepared specimens were evaluated by the following methods, and the results are shown in Tables 1 and 2 below.

Property evaluation method

(1) Flame retardancy: The flame retardancy of 0.8 mm and 1.5 mm thick specimens was measured by UL94 vertical test method.

(2) Tensile strength retention (unit:%): The tensile strength retention was calculated in accordance with the following formula (1).

[Formula 1]

Tensile strength retention (%) = TS ₁ / TS ₀ 100

TS ₀ is the initial tensile strength of the 3.2 mm thick specimen measured in accordance with ASTM D638 and TS ₁ is the tensile strength measured according to ASTM D638 after holding the specimen in an oven at 200 ° C for 500 hours, to be.

(3) Dielectric breakdown strength (unit: kV / mm): The dielectric breakdown strength of a 1 mm thick specimen was measured according to ASTM D149.

Example One 2 3 4 5 6 7 8 (A1) (% by weight) 39 38.2 37.5 39 38.2 37.8 37.5 37.1 (B) (% by weight) 13 12.8 12.5 13 12.8 12.7 12.5 12.4 (C1) (% by weight) 13 14 15 12 13 13 14 14 (D) (% by weight) 35 35 35 35 35 35 35 35 (E) (% by weight) - - - One One 1.5 One 1.5 Flammability (0.8 mm) V-0 V-0 V-0 V-0 V-0 V-0 V-0 V-0 Flammability (1.5 mm) V-0 V-0 V-0 V-0 V-0 V-0 V-0 V-0 Tensile strength retention (%) 99 89 90 95 100 96 92 92 Dielectric breakdown strength (kV / mm) 23 23 25 28 27 27 27 25

Comparative Example One 2 3 4 5 6 7 8 (A1) (% by weight) - - - - - 31 49 39 (A2) (% by weight) 39 38.2 37.5 39 38.2 - - - (B) (% by weight) 13 12.8 12.5 13 12.8 20 2 13 (C1) (% by weight) 13 14 15 12 13 14 14 - (C2) (% by weight) - - - - - - - 13 (D) (% by weight) 35 35 35 35 35 35 35 35 (E) (% by weight) - - - One One - - - Flammability (0.8 mm) V-1 V-1 V-1 V-1 V-0 V-2 V-1 V-1 Flammability (1.5 mm) V-1 V-0 V-0 V-1 V-1 V-1 V-1 V-0 Tensile strength retention (%) 83 79 76 86 85 76 83 65 Dielectric breakdown strength (kV / mm) 18 18 12 17 17 12 20 10

From the above results, it can be seen that the polyamide resin compositions (Examples 1 to 8) according to the present invention are excellent in flame retardancy, long-term heat stability (tensile strength retention), and withstand voltage characteristics (dielectric breakdown strength).

On the other hand, in Comparative Examples 1 to 5 using the polyamide 6T / 66 instead of the aromatic polyamide resin of the present invention, it was found that the withstand voltage characteristics were lowered and the flame retardancy and / or long-term heat stability were lowered. In Comparative Example 6 in which a small amount of resin was used and an aliphatic polyamide resin was used in excess, all of the flame retardancy, long-term heat resistance stability and withstand voltage characteristics were lowered. When the aromatic polyamide resin was used in an excessive amount, In the case of Comparative Example 7 used, flame retardancy and long-term heat stability were found to be lowered. Further, in the case of Comparative Example 8 using triphenyl phosphate instead of the phosphinic acid metal salt of the present invention, the flame retardancy (0.8 mm) was lowered and the long-term thermal stability and withstand voltage characteristics were largely lowered. It was confirmed that appearance defects also occurred.

It will be understood by those skilled 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.

Claims (11)

35 to 45% by weight of an aromatic polyamide resin comprising a repeating unit represented by the following formula (1), a repeating unit represented by the following formula (2) and a repeating unit represented by the following formula (3);
10 to 15% by weight of an aliphatic polyamide resin;
10 to 20% by weight of phosphinic acid metal salt; And
30 to 40% by weight of glass fibers;
And the insulation breakdown strength of the 1 mm thick specimen measured according to ASTM D149 is 20 to 30 kV / mm.
[Chemical Formula 1]

(2)

(3)

In the general formulas (1) and (2), R ₁ and R ₂ are each independently a hydrocarbon group having 1 to 6 carbon atoms or a halogen atom, and n ₁ and n ₂ are each independently an integer of 0 to 4.
The aromatic polyamide resin according to claim 1, wherein the aromatic polyamide resin comprises 55 to 75 mol% of the repeating unit represented by the formula (1), 20 to 30 mol% of the repeating unit represented by the formula (2) 15 mol% of the polyamide resin composition.
The polyamide resin composition according to claim 1, wherein the aromatic polyamide resin has a terminal carboxyl group concentration of 30 to 70 μeq / g and a terminal amine group concentration of 180 to 260 μeq / g.
4. The polyamide resin composition according to claim 3, wherein the aromatic polyamide resin has a ratio of terminal carboxyl groups and terminal amine groups of 1: 3.5 to 1: 7.5.
The polyamide resin composition according to claim 1, wherein the aliphatic polyamide resin comprises at least one of polyamide 6, polyamide 11, polyamide 12, polyamide 46, polyamide 66, and polyamide 610 Composition.
The polyamide resin composition according to claim 1, wherein the weight ratio of the aromatic polyamide resin to the aliphatic polyamide resin is 1: 0.2 to 1: 0.45.
The polyamide resin composition according to claim 1, wherein the polyamide resin composition further comprises a flame retardant adjuvant.
The polyamide resin composition according to claim 1, wherein the polyamide resin composition has a flame retardancy of V-0 or more of 0.8 mm or 1.5 mm thick specimens measured by UL-94 vertical test method.
The polyamide resin composition according to claim 1, wherein the polyamide resin composition has a tensile strength retention of 85% or more according to the following formula 1:
[Formula 1]
Tensile strength retention (%) = TS ₁ / TS ₀ 100
TS ₀ is the initial tensile strength of the 3.2 mm thick specimen measured in accordance with ASTM D638 and TS ₁ is the tensile strength measured according to ASTM D638 after holding the specimen in an oven at 200 ° C for 500 hours, to be.
delete A molded article formed from the polyamide resin composition according to any one of claims 1 to 9.