KR102192841B1 - Conductive polyamide resin composition, method for preparing the same and molding products comprising the same - Google Patents

Abstract

The present invention relates to a conductive polyamide resin composition, a method for producing the same, and a molded article comprising the same, and more particularly, to a polyamide resin, an aromatic vinyl compound-vinyl cyan compound copolymer, a vinyl cyan compound-conjugated diene compound-aromatic vinyl compound Copolymer, N-phenylmaleimide compound-aromatic vinyl compound copolymer, carbon fiber, polyether amide-based copolymer, and flow improver are blended within a specific content range to have high mechanical properties and electrical conductivity, while maintaining appearance quality and moldability. It relates to a reinforced conductive polyamide resin composition and the like.

Description

Conductive polyamide resin composition, its manufacturing method, and molded article {CONDUCTIVE POLYAMIDE RESIN COMPOSITION, METHOD FOR PREPARING THE SAME AND MOLDING PRODUCTS COMPRISING THE SAME}

The present invention relates to a conductive polyamide resin composition, a method for manufacturing the same, and a molded article, and more particularly, to a conductive polyamide resin composition having high mechanical properties and electrical conductivity while having excellent appearance quality and moldability, a method of manufacturing the same, and a molded article. About.

Polyamide resin, a kind of engineering plastic, has excellent mechanical strength, processability, durability, chemical resistance, weather resistance, etc., but its application is somewhat limited to use it alone. In particular, in order to use polyamide resin for electrical and electronic parts or industrial purposes, electromagnetic wave shielding properties are required or electrostatic painting treatment is performed, so a conductive filler component such as carbon black, carbon fiber, etc. to impart conductivity to the resin is performed. Ceramics and metal fibers are blended.

In addition, in order to improve the mechanical strength, heat resistance, and processability of the conductive polyamide resin, a thermoplastic elastomer, a compatibilizer, and the like are mixed and used.

For example, a conductive polyamide resin composition in which metal fibers and carbon fibers, modified polyolefins, and thermoplastic elastomers are mixed in a polyamide resin matrix has been known, but this is relatively inferior in conductivity and low in appearance quality, so that the appearance quality is relatively important. There was a problem that was not suitable for home appliance parts.

As another example, a composition in which carbon fibers, carbon black, and mineral fillers are added to a polyamide resin matrix to secure conductivity and amorphous polyamide are mixed together to improve appearance quality has been known, but this is a relatively mineral filler content. High conductivity is easy to secure, but the specific gravity is high, mechanical strength is low, and the appearance quality improvement effect is insufficient.

Accordingly, there is a need to develop a conductive polyamide resin composition having excellent appearance quality and processability while having high mechanical properties and electrical conductivity.

Korean Patent Application Publication No. 2015-0116781 A

In order to solve the problems of the prior art as described above, the present invention is to provide a conductive polyamide composition having excellent appearance quality and moldability while having high mechanical properties and electrical conductivity, and a high-quality conductive polyamide molded article manufactured including the same. The purpose.

Another object of the present invention is to provide a method for preparing the conductive polyamide composition.

All of the above and other objects of the present invention can be achieved by the present invention described below.

In order to achieve the above object, the present invention is a polyamide resin 35 to 50% by weight; 15 to 25% by weight of an aromatic vinyl compound-vinyl cyan compound copolymer; 5 to 10% by weight of a vinyl cyan compound-conjugated diene compound-aromatic vinyl compound copolymer; 3 to 8% by weight of an N-phenylmaleimide compound-aromatic vinyl compound copolymer; 18 to 35% by weight of carbon fiber; 0 to 20% by weight of a polyether amide copolymer; It provides a conductive polyamide resin composition comprising; and 0.1 to 3% by weight of a flow improver.

In addition, the present invention is a polyamide resin 35 to 50% by weight; 15 to 25% by weight of an aromatic vinyl compound-vinyl cyan compound copolymer; 5 to 10% by weight of a vinyl cyan compound-conjugated diene compound-aromatic vinyl compound copolymer; 3 to 8% by weight of an N-phenylmaleimide compound-aromatic vinyl compound copolymer; 18 to 35% by weight of carbon fiber; 0 to 20% by weight of a polyether amide copolymer; And it provides a method for producing a conductive polyamide resin composition comprising the step of kneading and extruding, including 0.1 to 3% by weight of the flow improver.

In addition, the present invention provides a molded article, characterized in that produced by including the conductive polyamide resin composition.

According to the present invention, there is an effect of providing a conductive polyamide resin composition having excellent appearance quality and moldability while having high mechanical strength and electrical conductivity.

In particular, the conductive polyamide resin composition according to the present invention has mechanical strength and heat resistance equivalent to or better than those of the known conductive polyamide resin composition, while enhancing moldability, appearance quality, and electrical conductivity to produce high-quality molded products. It can be provided, and there is an advantage that is particularly suitable as a component for home appliances.

Hereinafter, the conductive polyamide resin composition of the present invention will be described in detail.

The inventors of the present invention are polyamide resin with aromatic vinyl compound-vinyl cyan compound copolymer, vinyl cyan compound-conjugated diene compound-aromatic vinyl compound copolymer, N-phenylmaleimide compound-aromatic vinyl compound copolymer, carbon fiber, polyether amide By blending the copolymer and the flow improver within a specific content range, it was confirmed that the appearance quality and moldability, and high mechanical strength and electrical conductivity can be secured, and the present invention was completed based on this.

The conductive polyamide resin composition of the present invention comprises 35 to 50% by weight of a polyamide resin; 15 to 25% by weight of an aromatic vinyl compound-vinyl cyan compound copolymer; 5 to 10% by weight of a vinyl cyan compound-conjugated diene compound-aromatic vinyl compound copolymer; 3 to 8% by weight of an N-phenylmaleimide compound-aromatic vinyl compound copolymer; 18 to 35% by weight of carbon fiber; 0 to 20% by weight of a polyether amide copolymer; And 0.1 to 3% by weight of a flow improver.

The composition according to the present invention improves moldability by blending an aromatic vinyl compound-vinyl cyan compound copolymer, a vinyl cyan compound-conjugated diene compound-aromatic vinyl compound copolymer in a polyamide resin, and N-phenylmaleimide compound-aromatic A vinyl compound copolymer is blended to secure compatibility and mechanical strength, and a polyether amide copolymer and a flow improver are used to improve mechanical strength and conductivity by blending carbon fiber as a conductive filler while securing the appearance quality and flow index. It is characterized by blending.

In another example, the composition comprises 35 to 40% by weight of a polyamide resin; 15 to 20% by weight of an aromatic vinyl compound-vinyl cyan compound copolymer; 7 to 9% by weight of a vinyl cyan compound-conjugated diene compound-aromatic vinyl compound copolymer; 4 to 6% by weight of an N-phenylmaleimide compound-aromatic vinyl compound copolymer; 18 to 25% by weight of carbon fiber; 10 to 15% by weight of a polyether amide-based copolymer; And 0.5 to 1% by weight of a flow improver, and within this range, there is an advantage of further improving electrical conductivity and appearance quality while having excellent mechanical properties or moldability of the composition.

Hereinafter, the composition of the present invention will be described in detail for each component.

A. Polyamide resin

In the present invention, the polyamide resin is not particularly limited if it is within the range commonly used in the art, and may be appropriately selected. As a preferred example, polyamide 6, polyamide 66, polyamide 46, polyamide 11, polyamide 12 , Polyamide 610, Polyamide 612, Polyamide 6/66, Polyamide 6/612, Polyamide MXD6, Polyamide 6/MXD6, Polyamide 66/MXD6, Polyamide 6T, Polyamide 6I, Polyamide 6/6T , Polyamide 6/6I, polyamide 66/6T, polyamide 66/6I, polyamide 6/6T/6I, polyamide 66/6T/6I, polyamide 9T, polyamide 9I, polyamide 6/9T, poly At least one selected from the group consisting of amide 6/9I, polyamide 66/9T, polyamide 6/12/9T, polyamide 66/12/9T, polyamide 6/12/9I and polyamide 66/12/6I I can.

In a more preferred example, the polyamide resin may include polyamide 6, polyamide 66, or both, and both homopolymers and copolymers may be possible, and in this case, it is more excellent in terms of mechanical strength or processability of the final product. There is an advantage.

In the present invention, the polyamide resin may be included in an example of 35 to 50% by weight, 35 to 45% by weight, or 36 to 40% by weight of the total composition, within this range, such as flexural modulus, tensile strength, impact strength, etc. There is an effect of excellent physical property balance.

The polyamide resin may have, for example, a relative viscosity of 2.0 to 3.0 or 2.3 to 3.0, and has an advantage in that it is easy to process and mold while having excellent mechanical properties within this range.

In the present invention, the relative viscosity is measured at room temperature (23° C.) using 95 wt% sulfuric acid aqueous solution unless otherwise specified.

The polyamide resin may be characterized by having a melting temperature of 220 to 240°C or 220 to 230°C, for example, and in this case, there is an advantage in that the composition has excellent mechanical strength and is easy to process and mold.

The polyamide resin, for example, may be characterized in that the amine end group content is 50 to 80 microequivalents/gram, and when the amine end group content is more than 80 microequivalents/gram, the water absorption rate is increased and the rigidity is lowered. And, if it is less than 50 microequivalents/gram, there is a problem that compatibility is lowered and impact strength is lowered.

In the present invention, the amine end group content is measured through hydrochloric acid titration, for example.

B. Aromatic vinyl compound-vinyl cyan compound copolymer

In the present invention, the aromatic vinyl compound-vinyl cyan compound copolymer is formulated for the purpose of improving the moldability of the composition, and is included as an example of 15 to 25% by weight, 15 to 20% by weight or 15 to 18% by weight of the total composition. In this range, while maintaining high mechanical strength or electrical conductivity of the composition, it provides an advantage of easy molding and processing.

The aromatic vinyl compound is, for example, one or more selected from styrene, α-methylstyrene, p-methylstyrene, and vinyltoluene, and preferably includes styrene.

The vinyl cyan compound copolymer may be, for example, one or more selected from acrylonitrile, methacrylonitrile, and ethacrylonitrile, and preferably includes acrylonitrile.

As an example, the aromatic vinyl compound-vinyl cyan compound copolymer may include 70 to 90% by weight of an aromatic vinyl compound and 10 to 30% by weight of a vinyl cyan compound, preferably 73 to 80% by weight of an aromatic vinyl compound and vinyl It contains 20 to 27% by weight of a cyan compound. There is an advantage of improving the processing and moldability of the composition within the above range.

The aromatic vinyl compound-vinyl cyan compound copolymer may be characterized in that, for example, a melt index (220° C., load 10 kgf) is 55 to 80 g/10min or 60 to 70 g/10min, and processing of the composition within this range And it provides the advantage of easy molding.

The aromatic vinyl compound-vinyl cyan compound copolymer may be characterized by having a weight average molecular weight of 50,000 to 350,000 g/mol or 100,000 to 230,000 g/mol, for example, and has excellent moldability and physical properties within this range. have.

The method for preparing the aromatic vinyl compound-vinyl cyan compound copolymer is not particularly limited, but as a preferred example, emulsion polymerization, block polymerization, etc. may be possible, and it may be more preferable to be prepared by continuous block polymerization in terms of production cost. have.

C. Vinyl cyan compound-conjugated diene compound-aromatic vinyl compound copolymer

The vinyl cyan compound-conjugated diene compound-aromatic vinyl compound copolymer is formulated to improve mechanical strength and moldability of the composition, and may be included in an example of 5 to 10% by weight or 7 to 9% by weight of the total composition. . Within this range, it provides the advantage of easy molding and processing of the composition.

The conjugated diene compound may include one or more selected from butadiene, isoprene, and the like, and preferably includes butadiene.

Each of the vinyl cyan compound and the aromatic vinyl compound in the vinyl cyan compound-conjugated diene compound-aromatic vinyl compound copolymer may be the same compound as used in the vinyl cyan compound-aromatic vinyl compound copolymer.

In a specific example, the vinyl cyan compound-conjugated diene compound-aromatic vinyl compound copolymer may be an acrylonitrile-butadiene-styrene copolymer in which acrylonitrile and styrene are grafted on a butadiene rubber. In this case, the mechanical composition of the composition There is an advantage of more excellent strength and formability.

The vinyl cyan compound-conjugated diene compound-aromatic vinyl compound copolymer may be characterized in that, for example, a weight average molecular weight of 50,000 to 120,000 g/mol or 70,000 to 100,000 g/mol, and excellent fluidity and impact within this range It has the effect of having strength.

The vinyl cyan compound-conjugated diene compound-aromatic vinyl compound copolymer may, for example, be characterized in that the average particle diameter is 1000 to 5000Å, 2000 to 4000Å, or 2500 to 4000Å, and excellent impact strength and mechanical property balance within this range Provides an effect with

Unless otherwise stated in the present invention, the average particle diameter can be measured using an intensity Gaussian distribution by dynamic laser scattering in a latex state using Nicomp 380 equipment.

The vinyl cyan compound-conjugated diene compound-aromatic vinyl compound copolymer can be used, for example, prepared through emulsion polymerization, and in this case, mechanical properties such as impact strength are more excellent and properties are uniform.

D. N-phenylmaleimide compound-aromatic vinyl compound copolymer

The N-phenylmaleimide compound-aromatic vinyl compound copolymer is an aromatic polyamide resin; and an aromatic vinyl compound-vinyl cyan compound copolymer and a vinyl cyan compound-conjugated diene compound-aromatic vinyl compound copolymer; By improving the compatibility of the liver, it is possible to provide an effect of improving mechanical properties and, in addition, enhancing the heat resistance of the composition.

For example, the N-phenylmaleimide compound-aromatic vinyl compound copolymer may be included in 3 to 8% by weight or 4 to 6% by weight of the total composition, and in this case, if physical properties such as mechanical strength or conductivity of the composition are not reduced, As a result, the compatibility is improved and the balance of physical properties provides a more excellent effect.

The aromatic vinyl compound of the N-phenylmaleimide compound-aromatic vinyl compound copolymer may be, for example, the same compound as used in the aromatic vinyl compound-vinyl cyan compound copolymer.

The N-phenylmaleimide compound-aromatic vinyl compound copolymer includes, for example, 20 to 80% by weight or 30 to 70% by weight of the N-phenylmaleimide compound and 20 to 80% by weight or 30 to 70% by weight of polystyrene, Within this range, the heat resistance, mechanical strength, and the like of the composition provide further superior advantages.

The N-phenylmaleimide compound-aromatic vinyl compound copolymer may be a copolymer optionally further comprising maleic acid or anhydride thereof in an amount of more than 3 to 15% by weight or 5 to 12% by weight, if necessary. It provides the effect of improving mechanical strength and appearance quality by further improving the property.

The N-phenylmaleimide compound-aromatic vinyl compound copolymer may be characterized in that the weight average molecular weight is 80,000 to 180,000 g/mol or 100,000 to 150,000 g/mol, for example, and the moldability of the composition within this range While excellent, mechanical strength or heat resistance can be improved.

In the present invention, the weight average molecular weight can be measured using gel permeation chromatography (GPC) unless otherwise noted.

The N-phenylmaleimide compound-aromatic vinyl compound copolymer may be characterized in that, for example, a glass transition temperature of 180 to 250°C, 190 to 230°C, or 190 to 220°C, and within this range, the heat resistance of the composition or It provides the advantage of more excellent moldability.

In the present invention, the glass transition temperature is measured using a differential scanning calorimeter (DSC) unless otherwise specified.

E. Carbon fiber

The carbon fiber is a kind of conductive filler and provides high mechanical strength and electrical conductivity, and for example, may be included in 18 to 35% by weight, 18 to 25% by weight, or 18 to 22% by weight of the total composition, and within this range High electrical conductivity and mechanical strength can be secured without deteriorating the appearance quality or moldability of the composition.

The carbon fiber has a density of 1 to 5 g/cm ^{3, for example} Alternatively, it may be characterized in that 1 to 3 g/cm ³ , and in this case, there is an advantage of easy molding and processing of the composition.

The carbon fiber may be characterized by having a length of 3 to 10 mm or 4 to 8 mm, and a diameter of 3 to 20 μm or 3 to 8 μm, for example, and within this range, the appearance quality of the final product does not deteriorate, and the machine It may be possible to secure proper strength and electrical conductivity.

In the present invention, the diameter and length of the carbon fiber may be analyzed through a scanning electron microscope, for example.

As a preferred example, the carbon fiber may be surface-treated with an organic compound, and in this case, the physical properties may be further improved by preventing scattering during compounding.

The organic compound may be, for example, polyamide, and in this case, the dispersibility in the polyamide matrix resin is further maximized, which greatly contributes to improvement of physical properties.

F. Polyether amide copolymer

The polyether amide-based copolymer can improve electrical conductivity by increasing the dispersing rate of charge in the composition, and in addition, migration to the product surface, thereby improving the phenomenon that carbon fibers protrude to the product surface. It provides a synergy effect that improves the appearance quality of the product.

That is, the polyether amide-based copolymer serves as a conductive auxiliary agent and an appearance quality improving agent, and ultimately contributes to providing a high-quality molded article by improving the electrical conductivity as well as the appearance quality of the final product.

In the above aspect, the carbon fiber and polyether amide-based copolymer in the composition of the present invention may be included in a weight ratio of 1:0.16 to 1:0.95, 1:0.17 to 1:0.9 or 1:0.5 to 1:0.8, , While maintaining high processability and mechanical strength of the composition within this range, it is possible to provide an advantage in which the above-described synergistic effect is further maximized.

For example, the polyether amide-based copolymer is included in 0 to 20% by weight of the total composition, preferably 4 to 20% by weight or 10 to 15% by weight. Within this range, it is possible to improve the electrical conductivity without significantly lowering the mechanical strength of the composition, etc., and provides an advantage of improving the appearance quality of the final product.

The polyether amide-based copolymer may, for example, be characterized in that the surface resistance is 10 ⁴ to 10 ¹³ Ω/sq, 10 ⁵ to 10 ¹¹ Ω/sq, or 10 ⁶ to 10 ⁹ Ω/sq, and within this range There is an advantage in that the electrical conductivity of the final product is further maximized.

Unless otherwise specified in the present invention, the surface resistance is a value measured according to ASTM D257.

The polyether amide-based copolymer may, for example, be characterized in that the melting temperature is 180 to 240°C, 190 to 230°C, or 190 to 210°C, and within this range, the molding and processability of the composition do not significantly decrease, Electrical conductivity and appearance quality can be further improved.

The polyether amide-based copolymer includes, for example, a hygroscopic ionomer and a polyether amide, and the hygroscopic ionomer is a copolymer polymerized including, for example, ethylene and methacrylic acid, and the carboxyl groups of methacrylic acid are Zn, Na , Ca, NH ₄ It may be characterized by being partially substituted. In this case, it can contribute to the improvement of conductivity by lowering the electrical resistance value of the product surface.

The polyether amide includes a hard segment including an amide block and a soft segment including an ether block, and may be prepared by, for example, a condensation polymerization reaction of a polyamide block and a polyether block.

As another example, the polyether amide may be prepared by condensation polymerization of a polyamide having both ends sealed with a carboxylic acid and a polyether (polyether diol) having both ends sealed with a hydroxy group.

G. Flow Improvement System

The flow improver is added so as not to significantly decrease the flow index according to the blending of the aromatic vinyl compound-vinyl cyan compound copolymer and the vinyl cyan compound-conjugated diene compound-aromatic vinyl compound copolymer. It provides the advantage of improving the appearance quality and formability while maintaining high physical properties.

The flow improver may be included as an example of the total composition, as 0.1 to 3% by weight, 0.5 to 2% by weight, or 0.5 to 1% by weight, within this range, while maintaining high mechanical properties or electrical conductivity of the composition This provides an excellent effect.

For example, the flow improver may have a melting temperature of 50 to 80°C or 55 to 65°C. In this case, a polyamide resin, an aromatic vinyl compound-a vinyl cyan compound, a vinyl cyan compound-a conjugated diene compound-an aromatic vinyl compound It is possible to provide an effect of improving blendability with a copolymer and the like.

The flow improver may be characterized by having a flash point of 260 to 300°C or 265 to 280°C, for example, and has an advantage of excellent injection moldability and heat resistance within this range.

For example, the flow improver may be at least one selected from natural or synthetic wax, C _12-60 alcohol, C _12-60 carboxylic acid, alpha-hydroxy fatty acid, polyhydroxy fatty acid ester, and polyhydroxy fatty acid amide, and preferably Is to contain wax.

In addition, the flow improver may be a mixture of the wax and the polymer, and the polymer is, for example, an alpha olefin-styrene copolymer, polyethylene, an alpha olefin-isobutene copolymer, ethylene-propylene-styrene copolymer, butylene-ethylene. -It may be at least one selected from styrene copolymer, ethylene-vinyl acetate copolymer, ethylene-isobutylene copolymer, styrene-butadiene-styrene copolymer, styrene-ethylene/propylene-styrene copolymer, styrene-butadiene copolymer, etc. However, it is not limited thereto, and it is specified that it can be appropriately selected and carried out within the range commonly practiced in the art.

The composition of the present invention may optionally contain antioxidants, heat stabilizers, lubricants, UV stabilizers, antistatic agents (except for polyether amide copolymers), anti-drip agents, flame retardants, inorganic fillers (excluding carbon fibers), lubricants, nucleating agents, and It may further include one or more additives selected from the group consisting of processing aids, release agents, pigments, dyes, antibacterial agents, antiwear agents and coupling agents, and the content thereof is not particularly limited if it is within a range that does not significantly reduce the physical properties of the composition, Preferably, it may be included in 0.01 to 3% by weight or 0.1 to 1.5% by weight.

The composition of the present invention, for example, has a melt index (220°C, load 10kgf) of 3 g/10min or more, 5 to 15 g/10min, 6 to 15g/10min, 8 to 14g/10min, or 6 to 13 g/10min. Thus, it provides the advantage of easy molding and processing.

For example, the composition of the present invention has excellent electrical conductivity with a surface resistance of 6.5 X 10 ³ Ω/sq or less, 5.0 X 10 ³ to 1.0 X 10 ² Ω/sq or 1.0 Ω/sq to 9.9 X 10 ² Ω/sq. .

The composition of the present invention has a tensile strength of 145 to 200 MPa or 150 to 190 MPa; Flexural modulus of 8000 to 19000 MPa or 10,000 to 17000 MPa; And the impact strength is 50 to 150J / m or 60 to 100J / m; provides an advantage of excellent mechanical properties.

In addition, the composition of the present invention may be characterized in that it has excellent heat resistance with a heat deflection temperature of 150°C or higher, 157 to 200°C, or 170 to 195°C.

Hereinafter, a method of preparing the composition of the present invention will be described. The manufacturing method of the conductive polyamide resin composition according to the present invention shares all the technical characteristics of the conductive polyamide resin composition described above, and the overlapping description thereof will be omitted.

As an example, the method for preparing a conductive polyamide resin composition of the present invention includes 35 to 50% by weight of a polyamide resin; 15 to 25% by weight of an aromatic vinyl compound-vinyl cyan compound copolymer; 5 to 10% by weight of a vinyl cyan compound-conjugated diene compound-aromatic vinyl compound copolymer; 3 to 8% by weight of an N-phenylmaleimide compound-aromatic vinyl compound copolymer; 18 to 35% by weight of carbon fiber; 0 to 20% by weight of a polyether amide copolymer; And 0.1 to 3% by weight of the flow improver; It may be characterized in that it comprises the step of kneading and extruding.

The kneading and extrusion is 230 to 270 ℃ and 150 to 300rpm for example; Alternatively, it may be performed under conditions of 240 to 260° C. and 200 to 280 rpm, but is not limited thereto and may be performed by appropriately selecting within the range commonly practiced in the art.

The kneading and extrusion may be performed using a Banbari mixer, a single screw extruder, a twin screw extruder, a kneader reactor, etc., and is not particularly limited.

The present invention provides a molded article obtained by including the conductive polyamide resin composition.

The molded article manufactured including the composition of the present invention is characterized by having high mechanical properties and electrical conductivity and excellent appearance quality, and can be applied to various fields, but is particularly suitable for parts for home appliances where appearance quality is important. Has.

In describing the conductive polyamide resin composition of the present invention, its manufacturing method and molded article, other conditions that are not explicitly described are not particularly limited and are appropriately selected if they are within the range commonly practiced in the technical field to which the present invention belongs. State that you can.

Hereinafter, a preferred embodiment is presented to aid the understanding of the present invention, but the following examples are only illustrative of the present invention, and it is obvious to those skilled in the art that various changes and modifications are possible within the scope and spirit of the present invention, It is natural that such modifications and modifications fall within the appended claims.

Materials used in the following Examples and Comparative Examples are as follows.

A. Polyamide resin

When titrated with hydrochloric acid, the amine end group content is 50 to 80 microequivalents/gram, and when measured using a 95 wt% sulfuric acid aqueous solution, the polyamide 6 has a relative viscosity of 2.3 to 3.0 and a melting temperature of about 224°C. PA 6) was used.

B. Aromatic vinyl compound-vinyl cyan compound copolymer

A styrene-acrylonitrile copolymer (SAN) containing 23 to 26% by weight of acrylonitrile and 74 to 77% by weight of styrene and having a melt index (220°C, load 10kgf) of 60 to 70g/10min was used.

C. Vinyl cyan compound-conjugated diene compound-aromatic vinyl compound copolymer

As a copolymer in which an aromatic vinyl compound and a vinyl cyan compound were grafted to a conjugated diene rubber polymer through an emulsion polymerization method, an acrylonitrile-butadiene-styrene copolymer (ABS) having an average particle diameter of 2500 to 5000Å was used.

D. N-phenylmaleimide compound-aromatic vinyl compound copolymer

As a polystyrene resin (PMI-PS) grafted with N-phenylmaleimide, it contains 30 to 70% by weight of N-phenylmaleimide and 30 to 70% by weight of polystyrene, and has a weight average molecular weight of 120,000 g/mol and glass transition The one having a temperature of 200°C was used.

E. Carbon fiber

Carbon fibers (surface treated with polyamide) having a carbon content of 90% by weight, a density of 1 to 3 g/cm ³ , a diameter of 6 to 8 μm, and a length of 4 to 8 mm were used.

F. Polyether amide copolymer

A product containing a hygroscopic ionomer and a polyether amide copolymer, a surface resistance of 10 ⁶ to 10 ⁸ Ω/sq, and a melting temperature of about 200°C was used.

G. Flow Improvement System

A product having a melting temperature of about 60°C and a flash point of about 270°C was used, and specifically, Bruggolen P130 from Brueggemann Chemical was used.

[Example]

Example 1 to 5 and Comparative example 1 to 5

After each component was blended with the components and contents described in Table 1 below, it was melted and kneaded under conditions of 250°C using a twin screw extruder to obtain a conductive polyamide resin composition in the form of pellets. After drying this, a specimen for measuring physical properties was prepared using an 80ton Engel injection machine.

[Test Example]

The properties of the specimens prepared in the Examples and Comparative Examples were measured by the following method, and the results are shown in Table 1 below.

*Flow index [g/10min]: Measured under conditions of 250°C and load 2.16kgf according to ASTM D1238.

*Tensile strength [MPa]: According to ASTM D638, a specimen having a thickness of 3.2 mm was used and measured under conditions of a tensile rate of 5 mm/min.

* Flexural modulus [MPa]: According to ASTM D790, a specimen having a thickness of 3.2 mm was used, and the test speed was measured under conditions of 1.3 mm/min.

*Impact strength [J/m]: According to ASTM D256, a notch was made in a specimen having a thickness of 3.2mm and measured at room temperature (23°C).

*Heat deflection temperature [℃]: In accordance with ASTM D648, it was measured under 18.6kgf stress using a specimen having a thickness of 6.4mm.

*Surface resistance [Ω/sq]: In accordance with ASTM D257, it was measured at room temperature (23°C) using a Quadtech 1865 Megohmmeter/IR tester, and the standard of the specimen was 100mm X 100mm X 3mm.

*Appearance quality: The moldability during injection and the appearance of the specimen obtained after injection were evaluated visually. (◎: excellent both formability and appearance, ○: excellent both formability and appearance, △: good appearance, Χ: poor appearance, ΧΧ: very poor appearance)

division Example Comparative example One 2 3 4 5 One 2 3 4 5 PA 6 45 42 39 36 36 48 45 42 40 40 SAN 20 18 17 16 16 22 21 20 17 17 ABS 9 9 8 7 7 10 9 8 8 8 PMI-PS 5 5 5 5 5 - 5 5 5 5 Carbon fiber 20 20 20 20 30 20 20 20 15 - Carbon black - - - - - - - - - 15 Polyether
amides - 5 10 15 5 - - 3 15 15 Flow improvement system One One One One One - - - - - Flow index[g/10min] 8 9 9 9 8 4 2 2 3 2 Tensile strength [MPa] 172 155 150 145 183 180 173 162 90 45 Flexural modulus [MPa] 10500 10000 9500 8000 16500 11500 10800 10200 5000 3000 Impact strength [J/m] 80 84 88 93 65 50 75 78 73 40 Heat deflection temperature [℃] 180 176 174 157 190 185 180 178 110 95 Surface resistance
[Ω/sq] 6.5
x10 ³ 2.5
x10 ³ 9.8 x10 ² 2.0 x10 ² 8.5 x10 ² 6.5 x 10 ³ 6.5 x 10 ³ 6.5 x 10 ³ 6.5 x 10 ³ 7.0 x10 ⁵ Appearance quality ○ ◎ ◎ ◎ ○ ΧΧ Χ △ △ ΧΧ

(In the table above, the content of each component is a weight% of the total weight of the composition, and antioxidants and lubricants as additives were added in an amount of 0.1 to 1.5 parts by weight based on 100 parts by weight of the composition, but this is not specified separately.)

As shown in Table 1, the composition according to the present invention has excellent mechanical properties such as tensile strength, impact strength, flexural modulus, and thermal deformation temperature, and has an appropriate flow index, making it easy to process and mold, and has excellent electrical conductivity. Can be confirmed. In addition, it can be seen that the composition of the present invention has improved appearance quality.

In particular, in the case of Examples 2 to 5 in which carbon fibers and polyether amide were combined in a specific ratio, it was confirmed that the overall physical property balance was excellent and the appearance quality was further improved.

On the contrary, it can be seen that the resins of Comparative Examples 1 to 4 have a very low melting index, which is not desirable in terms of molding and processability, and mechanical properties and appearance quality are poor.

In particular, in the case of Comparative Example 1 without PMI-PS, the impact strength was considerably lower, and both Comparative Examples 1 and 2 did not contain polyether amide and a flow improving agent, so the flow index was lowered, and the appearance quality was considerably poor.

In addition, in the case of Comparative Example 5 in which carbon black was mixed instead of carbon fiber, it was quite poor in terms of mechanical properties and workability such as flow index, tensile strength, flexural modulus, and impact strength, and heat resistance was about half that of the Example, and appearance It can be seen that the quality is also poor.

Claims (18)

35 to 45% by weight of a polyamide resin; 15 to 18% by weight of an aromatic vinyl compound-vinyl cyan compound copolymer; 7 to 9% by weight of a vinyl cyan compound-conjugated diene compound-aromatic vinyl compound copolymer; 3 to 8% by weight of an N-phenylmaleimide compound-aromatic vinyl compound copolymer; 18 to 35% by weight of carbon fiber; 4 to 20% by weight of a polyether amide copolymer; And 0.5 to 2% by weight of the flow improver; Including,
Wherein the weight ratio of the carbon fiber and the polyether amide-based copolymer is 1:0.16 to 1:0.95
Conductive polyamide resin composition. delete The method of claim 1,
The polyamide resin has a relative viscosity of 2.0 to 3.0 and a melting temperature of 220 to 240°C.
Conductive polyamide resin composition. The method of claim 1,
The aromatic vinyl compound-vinyl cyan compound copolymer has a melt index (220° C., load 10 kgf) of 55 to 80 g/10 min.
Conductive polyamide resin composition. The method of claim 1,
The vinyl cyan compound-conjugated diene compound-aromatic vinyl compound copolymer has an average particle diameter of 1000 to 5000Å.
Conductive polyamide resin composition. The method of claim 1,
The N-phenylmaleimide compound-aromatic vinyl compound copolymer has a weight average molecular weight of 80,000 to 180,000 g/mol, and a glass transition temperature of 180 to 250°C.
Conductive polyamide resin composition. The method of claim 1,
The carbon fiber is characterized in that the density is 1 to 5g / cm ³
Conductive polyamide resin composition. The method of claim 1,
The carbon fiber is characterized in that the length is 3 to 10mm, the diameter is 3 to 20㎛
Conductive polyamide resin composition. The method of claim 1,
The polyether amide-based copolymer is characterized in that it comprises a hygroscopic ionomer and a polyether amide
Conductive polyamide resin composition. The method of claim 1,
The polyether amide-based copolymer has a surface resistance of 10 ⁴ to 10 ¹³ Ω/sq.
Conductive polyamide resin composition. The method of claim 1,
The polyether amide-based copolymer is characterized in that the melting temperature is 180 to 240 ℃
Conductive polyamide resin composition. The method of claim 1,
The flow improver, characterized in that the melting temperature is 50 to 80 ℃, the flash point is 260 to 300 ℃
Conductive polyamide resin composition. delete The method of claim 1,
The composition is characterized in that the melt index (220 ℃, load 10kgf) is 5g / 10min or more
Conductive polyamide resin composition. The method of claim 1,
The composition is characterized in that the surface resistance is 6.5 X 10 ³ Ω / sq or less
Conductive polyamide resin composition. 35 to 45% by weight of a polyamide resin; 15 to 18% by weight of an aromatic vinyl compound-vinyl cyan compound copolymer; 7 to 9% by weight of a vinyl cyan compound-conjugated diene compound-aromatic vinyl compound copolymer; 3 to 8% by weight of an N-phenylmaleimide compound-aromatic vinyl compound copolymer; 18 to 35% by weight of carbon fiber; 4 to 20% by weight of a polyether amide copolymer; And 0.5 to 2% by weight of the flow improver; comprising the step of kneading and extruding, wherein the weight ratio of the carbon fiber and the polyether amide-based copolymer is 1:0.16 to 1:0.95
Method for producing a conductive polyamide resin composition. A molded article comprising the conductive polyamide resin composition according to any one of claims 1, 3 to 12, or 14 to 15. The method of claim 17,
The molded article is characterized in that the parts for home appliances
Molded products.