KR102043301B1 - Polyamide resin composition and product prepared therefrom - Google Patents

Abstract

The present invention relates to a polyamide mixed resin comprising an aliphatic polyamide and an aromatic polyamide, a polyamide resin composition comprising a polyfunctional alcohol, a glass fiber and a azine compound, and a molded article produced therefrom.

Description

Polyamide resin composition and molded article manufactured therefrom {POLYAMIDE RESIN COMPOSITION AND PRODUCT PREPARED THEREFROM}

The present invention relates to a polyamide resin composition and a molded article produced therefrom. Specifically, the present invention relates to a polyamide resin composition having excellent mechanical rigidity and processability, and a molded article produced therefrom.

As regulations on greenhouse gas emissions and fuel economy around the world are tightened, there is a growing interest in improving fuel economy in transportation. In order to improve fuel efficiency of transportation mainly made of metal, the need for weight reduction is emerging as a method for developing metal replacement parts. Metals such as steel, which are mainly applied to transportation vehicles, have a lot of weight compared to excellent strength, and an attempt has been made to replace them with aluminum or magnesium, but the price is not competitive. Accordingly, various researches are being conducted on composite materials using thermoplastic resins having high weight reduction rate and cost competitiveness.

Thermoplastic resins include polyamide (PA), polyethylene terephthalate (PET), polybutylene terephthalate (PBT) and polyoxymethylene (POM).

Among them, polyamide not only has excellent physical properties such as heat resistance, abrasion resistance, chemical resistance, and flame retardancy, but also has a low specific gravity, which is advantageous for light weight and thus has high price competitiveness. In addition, the moldability is good, and the improvement of physical properties can also be expected by using glass fiber, and it is widely applied to automobile parts. However, it does not have the strength to replace the existing steel, there is a limit in the implementation of physical properties, such as not meeting the high level of heat resistance.

As described above, in order to realize the high performance of the composite material using the polyamide, compounding technology to which various fillers are added is essential, and a large amount of glass fiber is required. However, when a high content of glass fiber is added, the fluidity is not good, and when the physical properties are satisfied, the processability is poor, and molding is difficult through the existing extrusion process or injection process. The processability of the polymer is limited to improvement through the change of monomer, control of molecular weight and change of molecular structure. For this reason, flow control agents such as lubricants that affect the viscosity behavior of the melt as well as the choice of processing equipment should be used to improve processability. The addition of such additives requires a further additive to solve the deterioration of properties, such as a complicated process and a cost increase.

An object of the present invention for solving the above problems is to provide a polyamide resin composition having an excellent extrusion or injection processability even when the specific gravity is low and advantageous to light weight but very high content of glass fibers.

In addition, another object of the present invention is to provide a polyamide molded article that is clean and smooth in appearance while significantly improving mechanical strength by providing a polyamide resin composition that can realize excellent molding processability with excellent fluidity.

As a result of studying to achieve the above object, the polyamide resin composition according to the present invention comprises a polyamide mixed resin, a polyfunctional alcohol, a glass fiber and a azine compound containing an aliphatic polyamide and an aromatic polyamide.

The aliphatic polyamide and the aromatic polyamide according to an aspect of the present invention may include 80:20 to 20:80 weight ratio.

The polyamide resin composition according to an aspect of the present invention may include 25 to 55% by weight of polyamide mixed resin, 0.1 to 5% by weight of polyfunctional alcohol, 40 to 68% by weight of glass fiber and 0.1 to 5% by weight of azine compound. Can be.

The glass fiber according to an aspect of the present invention may have a ratio (L / D) of the longest length (L) to the longest diameter (D) in the cross section perpendicular to the longitudinal direction of 200 to 1,000.

The aliphatic polyamide according to an aspect of the present invention is polyamide 6, polyamide 66, polyamide 612, polyamide 11, polyamide 12, polyamide 46, polyamide 610, polyamide 910, polyamide 912, polyamide 1010, polyamide 1012, polyamide 1210, polyamide 1212 and the like, or any combination of two or more thereof, wherein the aromatic polyamide is polyamide 6I, polyamide 9I, polyamide 10I, polyamide 12I, polyamide 6T, poly One or a mixture of two or more selected from amide 9T, polyamide 10T, polyamide 12T, polyamide 6T6I, and the like.

The polyfunctional alcohol according to one embodiment of the present invention may contain 2 to 10 hydroxy groups in a molecule.

The azine-based compound according to an aspect of the present invention may be a phenazine-based compound.

The polyamide resin composition according to an aspect of the present invention may further include any one or a mixture of two or more selected from a primary antioxidant and a secondary antioxidant.

The polyamide molded article according to the present invention is obtained by extruding or injecting the polyamide resin composition described above.

The polyamide molded article according to one embodiment of the present invention may have a flexural modulus of 18 GPa or more measured according to KS M ISO 178.

The polyamide molded article according to an aspect of the present invention may have a spiral flow length of 60 cm or more.

The polyamide molded article according to an aspect of the present invention may have five or less surface defects due to glass fiber protrusion in an area of 10 cm × 10 cm.

The polyamide resin composition according to the present invention has an advantage of having an excellent extrusion or injection molding processability with excellent flowability while significantly increasing the content of glass fibers.

In addition, the molded article prepared from the polyamide resin composition according to the present invention is to provide a polyamide molded article with a clean appearance and smooth appearance with excellent molding processability while having a high mechanical strength such as flexural modulus.

Hereinafter, the polyamide resin composition and the molded article manufactured therefrom according to the present invention will be described in more detail with reference to the following examples. However, the following examples are merely for the purpose of describing the present invention in detail, and the present invention is not limited thereto and may be implemented in various forms.

Also, unless defined otherwise, all technical and scientific terms have the same meanings as commonly understood by one of ordinary skill in the art to which this invention belongs. The terminology used in the description herein is for the purpose of effectively describing particular embodiments only and is not intended to be limiting of the invention.

Unless otherwise defined in the present invention, "aliphatic polyamide" means not containing an aromatic ring in the molecular chain, "aromatic polyamide" is a concept corresponding to the aliphatic polyamide in the concept that contains an aromatic ring in the molecular chain Means that.

Polyamide molded articles are required to contain a large amount of glass fibers in order to improve mechanical strength. However, when a high content of glass fiber is added, the fluidity is not good, and when it satisfies physical properties, it is difficult to form through conventional extrusion process or injection process because of poor workability. Accordingly, there is a need for a polyamide resin composition capable of providing a polyamide molded article having high processability while satisfying mechanical strength by including a high content of glass fiber.

The present invention for achieving the above object relates to a polyamide resin composition excellent in extrusion or injection processability, and can significantly improve the mechanical strength and molded articles produced therefrom.

The present invention will be described in detail as follows.

The polyamide resin composition according to the present invention includes a polyamide mixed resin, a polyfunctional alcohol, a glass fiber, and a azine compound containing an aliphatic polyamide and an aromatic polyamide.

As the polyamide resin composition according to the present invention can significantly increase the content of glass fibers, mechanical strength such as flexural modulus can be remarkably improved. In addition to this, despite the high glass fiber content, it has excellent flowability and has excellent extrusion or injection processability, so that a polyamide molded article with a clean appearance and smoothness can be produced.

According to one aspect of the invention, the polyamide mixed resin is a mixed resin containing an aliphatic polyamide and an aromatic polyamide. By including a mixed resin containing both the aliphatic polyamide and the aromatic polyamide, it is possible to ensure high mechanical strength and heat resistance at the same time. In addition, molding with a clean and smooth appearance is possible with excellent extrusion or injection processability.

According to an aspect of the present invention, the aliphatic polyamide and the aromatic polyamide may be included in an 80:20 to 20:80 weight ratio. Preferably it may be included in 60:40 to 20:80 weight ratio. When mixed in the above content, it can have a high glass fiber impregnation rate, it can significantly improve the flexural modulus.

According to one aspect of the present invention, the type of the aliphatic polyamide and the aromatic polyamide is not particularly limited, but specific examples thereof are as follows. The aliphatic polyamide is polyamide 6, polyamide 66, polyamide 612, polyamide 11, polyamide 12, polyamide 46, polyamide 610, polyamide 910, polyamide 912, polyamide 1010, polyamide 1012, poly One or a mixture of two or more selected from amide 1210, polyamide 1212, and the like. The aromatic polyamide may be any one or a mixture of two or more selected from polyamide 6I, polyamide 9I, polyamide 10I, polyamide 12I, polyamide 6T, polyamide 9T, polyamide 10T, polyamide 12T, polyamide 6T6I, and the like. Can be. By including the polyamide as described above, it is possible to ensure excellent mechanical strength, and to control the crystallization temperature to secure excellent fluidity to improve the molding processability.

According to one aspect of the present invention, the aliphatic polyamide resin may have a glass transition temperature (T _g ) of 50 to 120 ° C, preferably 70 to 90 ° C. In addition, the melting point (T _m ) of the aliphatic polyamide resin may be used that is 230 to 260 ℃. When the above range is satisfied, high mechanical strength and heat resistance may be realized, but the present invention is not limited thereto.

According to an aspect of the present invention, the aliphatic polyamide resin may have a weight average molecular weight of 10,000 to 200,000 g / mol, preferably 50,000 to 150,000 g / mol. If the above range is satisfied, it is effective in terms of improving mechanical strength as well as heat resistance and chemical resistance, but it is not limited thereto.

According to an aspect of the present invention, the aromatic polyamide resin may have a glass transition temperature (T _g ) of 80 to 150 ° C, preferably 110 to 130 ° C. When the above range is satisfied, the molding processability may be improved with excellent fluidity in a range in which mechanical strength is not lowered, but this is not limited thereto.

According to an aspect of the present invention, the aromatic polyamide resin may have a weight average molecular weight of 10,000 to 200,000 g / mol, preferably 50,000 to 150,000 g / mol. If the above range is satisfied, it is effective in terms of improving mechanical strength as well as heat resistance and chemical resistance, but it is not limited thereto.

In the present invention, the polyamide mixed resin in the polyamide resin composition has poor fluidity due to its long polymer chain. The combination of the polyfunctional alcohol, glass fiber, and azine compound can prevent the deterioration of physical properties and provide a free volume, thereby greatly improving the fluidity.

According to an aspect of the present invention, the polyamide mixed resin may include 25 to 55 wt% based on the total weight of the polyamide resin composition. Preferably it may comprise 25 to 38% by weight. When included in the range as described above it is possible to further increase the glass fiber impregnation rate with excellent miscibility with the polyfunctional alcohol, glass fiber and azine compound, it is possible to secure the fluidity and processability.

In the present invention, the polyfunctional alcohol may control the fluidity of the polyamide resin composition by alcoholic reaction (alcoholysis) with the polyamide mixed resin.

According to one aspect of the present invention, the polyfunctional alcohol may be used without any limitation as long as it has a hydroxy group, but may preferably contain 2 to 10 hydroxy groups, more preferably 3 to 8 hydroxy groups. In addition, according to one aspect of the present invention, the molecular weight of the polyfunctional alcohol may be 100 to 500 g / mol, preferably 200 to 500 g / mol. In the case of containing the polyfunctional alcohol as described above, the fluidity can be improved without lowering the mechanical strength by the combination of the polyamide mixed resin, the glass fiber, and the azine compound.

According to an aspect of the present invention, the polyfunctional alcohol may be, for example, pentaerythritol, dipentaerythritol, tripentaerythritol, tripentaerythritol, glycerol, diglycerol, or triglycerol. (triglycerol) and sorbitol (sorbitol) may be any one or a mixture of two or more, but is not limited thereto. Preferably, the use of dipentaerythritol is effective to achieve the above object.

According to one aspect of the present invention, the polyfunctional alcohol may include 0.1 to 5% by weight, preferably 0.5 to 4% by weight, based on the total weight of the polyamide resin composition. When included in the range as described above, when mixed with the polyamide mixed resin, glass fiber and azine compound, the flexural modulus can be improved, the fluidity can be improved to improve the extrusion or injection processability.

  According to one aspect of the invention the glass fiber is included to implement a high flexural modulus.

The glass fiber according to an aspect of the present invention may include 40 to 68% by weight based on the total weight of the polyamide resin composition. Preferably it may contain 55 to 68% by weight, more preferably 60 to 68% by weight.

The glass fiber included in the existing polyamide resin composition was intended to be contained in a high content in order to improve the flexural modulus, but when glass fiber was provided at 55% by weight or more based on the total weight of the composition, fluidity was markedly lowered, resulting in processability. There was a problem that is greatly reduced.

On the contrary, the polyamide resin composition according to the present invention not only significantly improves the flexural modulus but also improves the extrusion or injection processability with excellent fluidity even when the glass fiber of 55% by weight or more is included relative to the total weight of the composition. Can be. This is an effect realized because it includes all of the polyamide mixed resin, polyfunctional alcohol, glass fiber and azine compound according to the present invention.

According to one aspect of the present invention, the above ratio is not particularly limited, but the longest length of the glass fiber may be 2 to 10 mm, and preferably 2 to 8 mm. The longest diameter of the glass fiber may be 1 to 50㎛, may be 1 to 20㎛, but is not limited thereto. When the above range is satisfied, mechanical strength improvement effects such as excellent flexural modulus can be obtained.

According to one aspect of the invention, the glass fiber may have a ratio (L / D) of the longest length (L) to the longest length (D) in the cross-section perpendicular to the longitudinal direction may be 200 to 1,000. Preferably, the ratio (L / D) may be 200 to 800. If the ratio is satisfied, even if the polyamide resin composition is included in a high content, it is possible to significantly improve the flexural modulus while ensuring fluidity.

In addition, the glass fiber may be used that has a cross-sectional shape of any one or more selected from a circle, an ellipse, a rectangle and a dumbbell, but is not limited thereto.

According to an aspect of the present invention, the glass fiber may reduce friction between the glass fibers, and may be sized to provide a bond between the polyamide resin compositions to further improve mechanical strength. More specifically, the glass fiber may be one that has been sized with a silane compound. Specific examples of the silane compound include γ-5-aminopropyltriethoxysilane, n-trimethoxy-silyl-propyl-ethylene-diamine, γ-glycidoxypropyltrimethoxysilane, and γ-methacryloxy Propyltrimethoxysilane, γ-β-aminoethyl-γ-aminopropyltrimethoxysilane, methyl-trichlorosilane, methyl-trimethoxysilane, γ-mercaptopropyl-trimethoxy-silane, γ-chloro Propyl-trimethoxy-silane, vinyl-triethoxy-silane, vinyl-tris- (2-methoxyethoxy) silane, vinyl-triacetoxy silane, octyltriethoxysilane, methyltriethoxysilane, methyl Trimethoxysilane and γ-ureido propyltrimethoxy silane, and the like, or any one or two or more mixtures thereof.

According to one aspect of the present invention, the sizing may be 0.01 to 2 parts by weight, preferably 0.02 to 1 part by weight, based on 100 parts by weight of the glass fiber, but is not limited thereto. When sizing treatment with the above content can improve the flexural modulus while improving the workability.

The azine compound according to the present invention means a heterocyclic compound having one or more nitrogen atoms.

According to one aspect of the present invention, the azine-based compound may be any one or a mixture of two or more selected from an oxazine-based compound, a phenazine-based compound and a thiazine-based compound. Preferably, the azine compound may be a phenazine compound.

When the azine-based compound is mixed with the polyamide mixed resin, the polyfunctional alcohol, and the glass fiber, not only the glass fiber impregnation rate in the polyamide resin composition can be improved, but also the flexural modulus can be improved. In addition, by controlling the crystallization temperature to secure the fluidity can provide a molded article excellent in appearance with excellent extrusion or injection processability.

According to one embodiment of the present invention, the azine-based compound may be any one or a mixture of two or more selected from, for example, nigrosin and induline.

According to one aspect of the present invention, the azine-based compound may include 0.1 to 5% by weight, and preferably 0.5 to 4% by weight, based on the total weight of the polyamide resin composition. When the above range is satisfied, the molded article having excellent appearance can be provided by securing extrusion or injection processability, and the flexural modulus can be improved.

According to one aspect of the present invention, the polyamide resin composition includes 25 to 55% by weight of polyamide mixed resin, 0.1 to 5% by weight of polyfunctional alcohol, 40 to 68% by weight of glass fiber and 0.1 to 5% by weight of azine compound can do. Preferably 25 to 38% by weight of polyamide mixed resin, 0.5 to 4% by weight of polyfunctional alcohol, 55 to 68% by weight of glass fibers and 0.5 to 4% by weight of the azine compound. By including the composition in the above range, the impregnation rate of the glass fiber can be increased to increase the flexural modulus. As such, although the impregnation rate of the glass fiber is significantly increased, the fluidity may be excellent, so that extrusion or injection processability may be significantly improved.

The polyamide resin composition according to an aspect of the present invention may further include any one or a mixture of two or more selected from primary antioxidants and secondary antioxidants in order to prevent degradation of physical properties due to oxidation during extrusion or injection processing. Can be.

The primary antioxidant is a phenolic antioxidant, which stabilizes radicals by inducing bonding of radicals generated in plastics with hydrogen in phenolic antioxidants as a result of processing and at the same time, the phenolic antioxidants themselves are converted into radicals and resonances. By effect or rearrangement of electrons, it remains in a stable form.

The primary antioxidant is not particularly limited as long as it is a phenol-based antioxidant that can be mixed with polyamide to prevent oxidation. Specific examples thereof include N, N'-hexane-1,6-diylbis (3- (3 , 5-di-tert-butyl-4-hydroxyphenyl) propionamide), N, N'-di-2butyl-1,4-phenylenediamine, 2,6-di-tert-butyl-4-methyl Phenol, 2,4-dimethyl-6-tert-butylphenol, 2,6-di-tert-butylphenol, 2,2'-ethylidene-bis (4,6-di-tert-butylphenol), 2, 2'-methylene-bis (6-tert-butyl-4-methylphenol), 4,4'-butylidene-bis (2-tert-butyl-5-fetylphenol), 4,4'-thiobis ( 2-tert-butyl-5-methylphenol) and octadecyl 3- (3,5-di-tert-butyl-4'-hydroxyphenol) propionate and the like, or a mixture of two or more thereof, It is not necessarily limited thereto.

The secondary antioxidant is a phosphite-based antioxidant, it can effectively prevent the generation of radicals by performing the function of the peroxide decomposition agent. This is a synergistic effect in combination with the primary antioxidant, it is more effective in terms of improving the stability to the ultraviolet. The secondary antioxidant is not particularly limited as long as it is a phosphite-based antioxidant which can be mixed with polyamide to prevent oxidation, preferably tris (2,4-di-tert-butylphenyl) phosphite, triphenyl phosph Any selected from among phytes, tris (nonylphenyl) phosphite, triisodecyl phosphite, diphenyl-isooctyl-phosphite and bis (2,6-di-tert-butyl-4-methylphenyl) pentaerythritol-diphosphite It may be one or a mixture of two or more, but is not limited thereto.

According to an aspect of the present invention, the antioxidant may further include 0.1 to 0.5 parts by weight based on 100 parts by weight of the polyamide mixed resin in the polyamide resin composition, but is not limited thereto. When the above range is satisfied, it is possible to prevent a decrease in physical properties due to oxidation during processing, and further improve molding processability.

Hereinafter, the polyamide molded article according to the present invention will be described.

The polyamide molded article according to the present invention may be obtained by extruding or injecting the polyamide resin composition described above.

The polyamide molded articles not only have high flexural modulus but also can provide a clean and smooth surface with excellent appearance.

According to one aspect of the present invention, the polyamide molded article may have a flexural modulus of 18 GPa or more measured according to KS M ISO 178. Preferably, the flexural modulus may be 20 GPa or more. Specifically, the flexural modulus may be 18 to 40 GPa, and preferably 20 to 40 GPa. Conventional polyamide resin composition is difficult to have a glass fiber impregnation rate of 55% by weight or more, but it was not possible to have a high flexural modulus as described above, the polyamide resin composition according to the present invention can realize a high glass fiber impregnation rate is significantly high It may have a flexural modulus.

According to one aspect of the present invention, the polyamide molded article may have a spiral flow length of 60 cm or more. Preferably the spiral flow (spiral flow) length may be 70 cm or more. Specifically, the spiral flow may have a length of 60 to 90 cm. Preferably, the spiral flow length may be 70 to 90 cm. In order to implement the spiral flow as described above, the polyamide resin composition according to the present invention may have the spiral flow by improving the extrusion or injection processability with excellent flowability despite the high glass fiber impregnation rate.

According to one aspect of the present invention, the polyamide molded article may have five or less surface defects due to glass fiber protrusion in an area of 10 cm × 10 cm. Preferably, the surface defects due to the glass fiber protruding in an area of 10 cm × 10 cm may be three or less. As described above, the molded article of polyamide according to the present invention can be processed to have a clean and smooth appearance with less surface defects due to glass fiber protrusion.

The molded article manufactured by extruding or injecting the polyamide resin composition according to the present invention may be applied to automobile parts requiring high mechanical strength due to excellent flexural modulus and excellent appearance.

Hereinafter, the present invention will be described in detail with reference to Examples. However, these are intended to explain the present invention in more detail, and the scope of the present invention is not limited by the following examples.

In addition, the unit of the additive which is not specifically described in the specification may be wt%.

[Measurement of physical properties]

1. Flexural Modulus

The flexural modulus of the polyamide molded articles prepared in Examples and Comparative Examples according to the present invention was measured based on KS M ISO 178.

2. Spiral Flow

The spiral flow of the polyamide molded articles prepared according to the examples and comparative examples according to the present invention was measured. The spiral flow was carried out in an injection machine (PRO-80MC (Dongshin Hydraulic)) at an injection temperature of 300 ℃ and an injection pressure of 80kgf / ㎠.

3. Appearance and Extrusion Processability

The appearance and extrusion processability of the polyamide molded articles prepared in Examples and Comparative Examples according to the present invention were evaluated as follows.

(Double-circle): It is excellent in workability and it is clean and smooth with less than 3 surface defects by glass fiber protrusion.

(Circle): There is no workability problem, and the glass fiber protrusions are five or less in appearance.

(Triangle | delta): Although continuous processing is possible, it is 6-10 glass fiber protrusions in an external appearance.

X: Continuous processing is not possible, and unevenness is severe as there are 10 or more glass fiber protrusions on the exterior.

Example 1

Polyamide 6,6 (Ascend 21ZLV, RV 2.4) and Polyamide 6, I (Evonik M5000) 33% by weight of polyamide mixed resin, 65% by weight of glass fiber (Owens Corning T983) A polyamide resin composition was prepared by mixing%, 1% by weight of pentaerythritol (tablet, purity 94%) and 1% by weight of nigrosine (Spirit Black SZ from Orient). To 100 parts by weight of the polyamide resin composition, an antioxidant was prepared by mixing 0.2 parts by weight of each of primary (Irganox 1098 from Basf) and secondary (Irgafos 168 from Basf). The polyamide resin composition was placed in a coaxial twin screw extruder having a diameter of 30 mm and L / D of 40, mixed, and extruded in pellet form. At this time, the conditions of the extruder at the time of mixing was extruder 200/230/270/280/270/270/270/280/290 ° C heating section, the screw rotation speed was 300rpm. The manufactured pellets were manufactured using a 80 Ton injection molding machine set at 300 ° C. for evaluation of physical properties.

Example 2

In Example 1, except that polyamide 6,6 and polyamide 6, I was mixed in a 1: 1 weight ratio, the same procedure was followed.

 Example 3

The same procedure as in Example 1 was carried out except that a mixed resin in which polyamide 6,6 and polyamide 6, I were mixed at a 3: 1 weight ratio was used.

Example 4

In Example 1, it was carried out in the same manner, except that 38% by weight of polyamide mixed resin and 60% by weight of glass fiber.

Example 5

In Example 1, it was carried out in the same manner except for changing to 68% by weight of polyamide resin and 30% by weight of glass fiber.

Example 6

In Example 1, it was carried out in the same manner except for changing to 48% by weight of polyamide mixed resin and 50% by weight of glass fiber.

Example 7

In Example 1, it was carried out in the same manner except that the polyamide mixed resin was changed to 28% by weight and 70% by weight of glass fiber.

Example 8

In Example 1, it was carried out in the same manner except that the polyamide mixed resin was changed to 29% by weight and 5% by weight of dipentaerythritol.

Example 9

In Example 1, it was carried out in the same manner except that the polyamide mixed resin was changed to 29% by weight and 5% by weight of nigrosine.

Comparative Example 1

In Example 1, the same procedure was followed except that the polyamide mixed resin was used as the polyamide 6,6 single resin.

Comparative Example 2

In Example 1, the same procedure was followed except that the polyamide mixed resin was used as the polyamide 6, I single resin.

Comparative Example 3

In Example 1, it was carried out in the same manner except that 35% by weight of the polyamide mixed resin was used without using dipentaerythritol and nigrosine.

[Comparative Example 4]

In Example 1, except that nigrosine was not used, except that 34% by weight of polyamide mixed resin was used.

The physical properties of the polyamide molded articles prepared in Examples and Comparative Examples according to the present invention were measured and shown in Table 1 below.

Flexural modulus
(GPa) Spiral flow
(Cm) Appearance and Extrusion Example 1 21.3 72 ◎ Example 2 20.8 70 ◎ Example 3 19.7 67 ◎ Example 4 20.5 70 ◎ Example 5 8.0 73 ◎ Example 6 15.5 68 ○ Example 7 19.3 42 X Example 8 14.3 70 △ Example 9 15.1 61 ○ Comparative Example 1 18.5 68 △ Comparative Example 2 14.5 50 ○ Comparative Example 3 16.0 49 △ Comparative Example 4 16.2 58 △

As shown in Table 1, it can be confirmed that the polyamide molded article made of the polyamide resin composition according to the present invention has high flexural modulus and extrusion or injection processability.

In particular, when the polyamide resin composition according to the present invention contains 25 to 38% by weight of polyamide mixed resin, 0.5 to 4% by weight of polyfunctional alcohol, 55 to 68% by weight of glass fiber and 0.5 to 4% by weight of azine compound, It can be confirmed that it has more excellent flexural modulus and molding processability and is excellent in appearance.

Furthermore, when the polyamide mixed resin of the polyamide resin composition satisfies the 80:20 to 40:60 weight ratio, it can be seen that high flexural modulus and fluidity of 20 GPa or more can be expressed.

In the case of Comparative Examples 1 and 2 by using an aliphatic or aromatic aromatic polyamide alone without including the polyamide mixed resin, it can be confirmed that not only the workability is poor but also the flexural modulus is reduced.

As Comparative Example 3 does not contain a polyfunctional alcohol and a azine compound, it can be seen that the surface defects due to the glass fiber protrusion on the appearance increases, and the flexural modulus and workability are significantly reduced.

Comparative Example 4 As it does not contain the azine compound, it can be seen that the surface defect due to the glass fiber protrusion on the appearance increases, and the flexural modulus and the workability are significantly reduced.

The polyamide resin composition according to the present invention through a comparative example includes all of the polyamide mixed resin, glass fiber, polyfunctional alcohol and azine-based compound, thereby providing a molded article having excellent flexural modulus and moldability and having a clean and smooth appearance. It can be seen that it can provide.

In addition, the polyamide resin composition according to the present invention, despite having a glass fiber impregnation rate of 55% by weight or more, not only high flexural modulus but also excellent flowability and excellent workability, thus providing a clean and smooth appearance without surface defects caused by glass fiber protrusion. The polyamide molded article which has is provided. As a result, it can be applied to automobile parts requiring excellent mechanical strength and appearance.

The present invention described above is merely illustrative, and those skilled in the art will appreciate that various modifications and equivalent other embodiments are possible therefrom. Therefore, it will be understood that the present invention is not limited to the forms mentioned in the above detailed description. Therefore, the true technical protection scope of the present invention will be defined by the technical spirit of the appended claims.

Therefore, the spirit of the present invention should not be limited to the described embodiments, and all of the equivalents or equivalents of the claims as well as the claims to be described later belong to the scope of the present invention. .

Claims (12)

25 to 55% by weight of polyamide mixed resin comprising polyamide 6,6 and polyamide 6, I in an 80:20 to 20:80 weight ratio, 0.1 to 5% by weight of polyfunctional alcohol, 40 to 68% by weight of glass fiber, and As a composition containing 0.1 to 5% by weight of a azine compound,
The composition has a flexural modulus of 18 GPa or more, a spiral flow length of 60 cm or more, measured by KS M ISO 178, when extruded or injection molded by glass fiber protruding in an area of 10 cm × 10 cm. The polyamide resin composition whose surface defects are five or less. delete delete The method of claim 1,
The glass fiber is a polyamide resin composition having a ratio (L / D) of the longest length (L) to the longest length (D) in the cross-sectional view perpendicular to the longitudinal direction. delete The method of claim 1,
The polyfunctional alcohol is a polyamide resin composition containing 2 to 10 hydroxyl groups in the molecule. The method of claim 1,
The azine compound is a polyamide resin composition is a phenazine compound. The method of claim 1,
The polyamide resin composition further comprises any one or a mixture of two or more selected from a primary antioxidant and a secondary antioxidant. A polyamide molded article obtained by extruding or injecting the polyamide resin composition according to any one of claims 1, 4 and 6 to 8. delete delete delete