KR20090062784A - Polyamide resin composition - Google Patents

Abstract

A polyamide resin composition is provided to ensure excellent bending elasticity, impact strength, forming shrinkage, heat deformation temperature, and surface appearance. A polyamide resin composition has the following physical properties: (i) impact strength by the ASTM evaluation method D256 is 13 kg.cm/cm or greater; (ii) flextural modulus by the ASTM evaluation method D790 is 40,000 kg/cm^2 or greater; (iii) forming shrinkage by the ASTM evaluation method D960 is 0.8 % or less; and (iv) heat deformation temperature by the ASTM evaluation method D648 is 190 °C or greater.

Description

Polyamide Resin Composition {POLYAMIDE RESIN COMPOSITION}

The present invention relates to a polyamide resin composition, and more particularly, to reinforce a filler of glass fibers in a polyamide resin composition, and to apply a rubber elastomer and an aromatic vinyl copolymer called an impact agent to apply to automobile parts or industrial parts. It relates to a polyamide resin composition having the following suitable physical properties.

In general, polyamide resins have excellent mechanical strength, heat resistance, chemical resistance, abrasion resistance, electrical insulation, arc resistance, and the like, and are widely used in all industrial fields such as automotive interiors, exteriors, engine parts, electrical and electronic parts, sports articles, and industrial materials. It is used for a wide range of applications, and especially has been applied to parts requiring excellent durability due to its excellent mechanical strength. However, polyamide resin is a crystalline resin, despite its advantages and many uses, it is weak in impact strength, has high molding shrinkage, and has a hydrophilic amide functional group, and thus has a high water absorption rate and is easily surfaced when exposed to high heat or ultraviolet rays. It has the disadvantage of being oxidized.

In addition, in order to apply polyamide resin to automotive parts, a functionalization technique for adding various reinforcing materials or additives is required, and a technique for adding glass fibers, minerals, carbon fibers, etc., which are typical reinforcing materials, is well known. Components using this reinforcement technology include cylinder head cover, air intake manifold, outside door handle, radiator head tank, front end module ( Carrier parts of the Front End Module are the core products of high-performance automobiles, and their physical properties require aluminum or higher.

With the recent automobile module (Module) among the various parts, the carrier part of the front-end module is a plastic part that is gradually plasticized recently, and is rapidly applied to the polyamide glass fiber reinforced material by using an overmolding method. have.

On the other hand, the following various technologies have been proposed and commercialized for polyamide resins.

First, US Pat. No. 5,851,238 and US Pat. No. 5,814,107 proposed a study to improve performance by adding an antioxidant or a weathering stabilizer to a polyamide resin. However, in the above methods, an antioxidant or a weathering stabilizer greatly deteriorates the mechanical properties of the polyamide resin.

The method refers to some techniques of fractional high functional polyamide resins, and a method widely known as a representative technique for preparing high functional polyamide resins is to polymerize polyamide resins to prepare new resins or to form other polymers and alloys. The technique of adding and reinforcing an inorganic filler to a polyamide resin according to the method and use of (Alloy) is well known. Since the technology produced by the polymerization takes a lot of time and high cost, many of the alloy techniques with other polymers have been proposed. The alloys with other polymers are mainly alloys with general-purpose plastics or thermoplastic rubber elastomers, alloys with other ENPLAs, and the alloys to be alloyed are polypropylene-based, polystyrene-based, and olefin-based elastomeric polyphenylenes. Oxides, and the like, and these are incompatible with polyamides, thereby producing functional polyamides through commercialization techniques.

In addition, in the case of the inorganic filler reinforced polyamide resin which is the most known technique, US Patent No. 5086105 or European Patent No. 1312 647 is added with a polyolefin elastomer to solve the problem of poor impact resistance caused by the inorganic filler reinforcement Later, he proposed a technique to strengthen the weapon filler. However, the above methods have a disadvantage in that the heat resistance is drastically lowered and the surface is poor during molding, so that only the limited use is possible.

As another technique, US Patent No. 5039719 proposes a technique of adding an inorganic filler and adding a substance having an unsaturated carboxyl group to promote compatibility. However, in the case of the carboxyl group-containing composition in addition to the inorganic filler as described above, molding restrictions are imposed on the use of large products or thin products with an increase in viscosity.

Other Another proposed technique is described in European Patent No. 117998, which adds an inorganic filler such as glass fiber but further adds a coupling agent to enhance adhesion with the polyamide resin. However, this technique has a disadvantage in that weather resistance or long-term heat resistance is insufficient due to the addition of the coupling agent and there is a problem that increases the manufacturing cost. U.S. Pat.No. 5,288,786 also discloses a method of adding olefins and their impact modifiers, but there is a limit to the application of high modulus to products desired.

In addition, U.S. Patent No. 52626284 attempts to improve the stiffness and heat resistance by adding nanoomers to polyamide resins, but the nanomers themselves have limitations in overcoming physical properties such as impact strength due to inadequate reactivity with polyamide resins. The addition of nanomers has a problem that the manufacturing cost rises.

As described above, the prior art is a technique for aligning polyamide resin alone or other heterogeneous polymers, and adding a coupling agent or an elastomer, and the like. Physical properties depend on other polymers and additives, and are intended to be applied to automobiles and electrical and electronic components. In addition, in the case of the conventional polyamide resin composition, there were many limitations in performance and enlargement molding in commercial application.

The present invention is to provide a polyamide resin composition and a polyamide resin molded article using the same having excellent mechanical strength, impact resistance, dimensional stability, and moldability, which can be applied to automobile parts or industrial parts.

In order to achieve the above technical problem, the present invention provides an impact strength of 13 kg · cm / cm or more according to ASTM evaluation method D256, a flexural modulus of 40,000 kg / cm 2 or more according to ASTM evaluation method D790, and an ASTM evaluation method D960. Provided is a polyamide resin composition having a molding shrinkage of 0.8% or less and having a physical deformation temperature of 190 ° C or higher according to ASTM Evaluation Method D648.

More preferably, the composition is formed in the flow direction of the specimen by the impact strength of 13 to 25 kg · cm / cm according to ASTM evaluation method D256, flexural modulus of 40,000 to 100,000 kg / cm 2 by ASTM evaluation method D790, ASTM evaluation method D960 Shrinkage is 0.8-0.4%, and the thermal deformation temperature according to ASTM evaluation method D648 has a property of 190 to 255 ℃.

Moreover, the said polyamide resin composition is (alpha), (beta)-unsaturated carboxylic acid with respect to (a) 50-80 weight% of polyamide resins, (b) 15-40 weight% of glass fibers, (c) 100 weight part of rubber elastomers, Α, β-unsaturated carboxylic acid, based on 3 to 10% by weight of the acid-modified rubber elastomer grafted 0.5 to 5 parts by weight of its anhydride or derivative thereof, and (d) 100 parts by weight of the aromatic vinyl monomer and polyphenyl maleimide as the main chain, 0.5 to 2 parts by weight of the anhydride or derivative thereof, and 2 to 8% by weight of the grafted aromatic vinyl copolymer.

Moreover, this invention provides the polyamide resin molded article containing the said polyamide resin composition.

Hereinafter, the present invention will be described in detail.

The polyamide resin composition of the present invention is excellent in mechanical strength, including glass fibers, and can improve the impact resistance and dimensional stability insufficient by adding acid-modified rubber elastomer and aromatic vinyl copolymer, and at the same time the surface quality of the product during molding It relates to a polyamide resin composition that can satisfy.

In addition, recently, the emotional quality, which is the appearance quality of the product, has also emerged as one of the important required performances, and demands the quality of mechanical strength or heat resistance level, and the polyamide resin composition of the present invention can satisfy all of these conditions. Particularly, in the case of acid-modified rubber elastomers added to improve impact resistance and aromatic vinyl copolymers added to solve surface problems and dimensional stability during molding, compatibility problems with polyamide resins may occur. In case of this technical problem is solved.

The polyamide resin used in the composition of the present invention is superior in the reinforcing effect of the inorganic filler compared to other resins. Due to these features, mineral reinforcement technology is more diverse than other technicalities and has many technical areas. The polyamide resin composition of the present invention can also be seen in the field of such inorganic reinforcing techniques.

Accordingly, the present invention provides a composition that is suitable for each desired property, improves the problems of the prior art and is capable of forming a high-performance product which is economically and widely available commercially.

That is, the present invention uses a polyamide resin as a base resin, and using an acid-modified rubber elastic body called an impact agent to secure impact resistance by adding a glass fiber, which is an inorganic material, to prevent rigidity, warpage and deformation, Additional aromatic vinyl copolymer is added to improve dimensional stability and stiffness, and in particular, surface defects during molding caused by the addition of glass fiber and impact resistant agent, such as surface fiber appearance and flow mark generation defects. By improving the polyamide resin composition that can achieve the desired purpose to complete the present invention.

In other words, the present invention overcomes the dimensional nonuniformity caused by the flexural modulus, which is roughly classified by rigidity, the impact strength, which is roughly classified by impact resistance, and the high mold shrinkage rate when the product is solidified, and the polyamide resin is used to enhance the surface of the molded article. The desired object was achieved by adding glass fibers and blending them with the acid-modified rubber elastomer and the aromatic vinyl copolymer in which a chemical reaction group is present.

In the polyamide resin composition of the present invention, the polyamide resin may be used 50 to 80% by weight based on the total polyamide composition. At this time, if the content is less than 50% by weight, the moldability is poor, the surface defects of the product is increased, if the content exceeds 80% by weight may contain a relatively low content of other materials, heat resistance and impact strength can be lowered.

Although the kind is not specifically limited in the polyamide resin used by this invention, Polyamide 6, polyamide 66, or its mixture can be used. In addition, the polyamide resin of the present invention can be preferably dried in a dehumidifying dryer to make a chip shape, preferably in the form of chips. In addition, the polyamide resin of the present invention is not particularly limited, but it is preferable to use a relative viscosity of 2.1 to 3.5 (based on a solution of 1 g of polymer in 100 mL of 20 ° C. and 96% sulfuric acid). If the relative viscosity of the polyamide resin used is less than 2.1, it may cause a decrease in rigidity and impact resistance, and if it exceeds 3.5, the surface display phenomenon of the inorganic material used as poor fluidity and the difficulty of molding may occur.

In addition, the glass fiber in the present invention is preferably used in an amount of 15 to 40% by weight based on the total composition. If the content is used less than 15% by weight can lead to a decrease in the flexural modulus, heat deformation temperature, if the content exceeds 40% by weight may be inadequate improvement in shrinkage anisotropy.

The glass fiber is not particularly limited since the glass fiber can be used in the technical field to which the present invention belongs. As a preferred example, the glass fiber may be a glass fiber in the form of Chop, commonly used as "G" or "K" glass. Its main component is a CaO.SiO ₂ .Al ₂ O _3, it is preferable that CaO is 10 to 20 wt%, SiO ₂ of 50 to 70 wt%, Al ₂ O ₃ consisting of 2 to 15% by weight and, the end Coupling with a silane is preferred on the glass fiber surface for interfacial adhesion with the composition. In particular, it is preferable that the average diameter of the glass fiber used by this invention is 10-13 micrometers, and the average length is 3-6 mm.

The acid-modified rubber elastomer of the present invention improves the impact resistance of the composition and is additionally added as a water resistant modifier. The content of such acid-modified rubber elastomer is preferably included in 3 to 10% by weight based on the total composition. In this case, if the content is less than 3% by weight, the effect of improving the impact strength is insignificant, and if the content exceeds 10% by weight, heat resistance and rigidity are lowered, the mold shrinkage is increased, and the surface is poor in molding.

The acid-modified rubber elastomer may be an acid-modified rubber elastomer in which a reactive dicarboxylic acid or its anhydride α, β-unsaturated dicarboxylic acid or its anhydride is grafted to 0.5 to 5 parts by weight based on 100 parts by weight of the rubber elastomer. Can be. When the content of the α, β-unsaturated carboxylic acid, its anhydride and derivatives thereof is less than 0.5 parts by weight, compatibility with the polyamide resin is inferior, and when it exceeds 5 parts by weight, kneading becomes difficult with high viscosity increase and the surface of the molded article The quality is poor. Such grafting is usually carried out on solvents or on molten olefins in the presence of peroxides and such grafting techniques are known.

The rubber elastomer may be prepared from one or more unsaturated monomers selected from the group consisting of α-olefins including ethylene, acrylic acid and its derivatives, aromatic vinyl monomers, and diene monomers. The α-olefins are saturated carboxylic acids such as ethylene, propylene, butylene, 1-pentene, isobutylene, isoprene, 1-hexene, 1,3-hexadiene and 1-hetene, vinyl acetate and propionate. Vinyl ester of the compound. The acrylic acid and its derivatives include methacrylate, methyl acrylate, butyl acrylate, glycidyl acrylate, ethyl methacrylate, 2-ethylhexyl methacrylate, amino methacrylate and glycidyl methacrylate, Maleimide compounds such as N-phenylmaleimide, N-methylmaleimide, and N-cyclohexylmaleimide. Examples of the aromatic vinyl monomers include styrene, α-methyl styrene, o-methyl styrene, p-methyl styrene, tetrabutyl styrene, dimethyl styrene, chlorostyrene, dichloro styrene, and vinyl naphthalene. Examples of the vinyl cyanide monomers include acrylonitrile, methacrylonitrile and fumaronitrile. The diene monomers include butadiene, 1.3-cyclohexadiene, 1,4-cyclohexadiene, cyclopentadiene and 2,4-hexadiene.

Also, the grafted α, β-unsaturated carboxylic acids, anhydrides and derivatives thereof are functional groups having excellent reactivity with amide groups such as maleic acid, itaconic acid, citraconic acid, acrylic acid, methacrylic acid, allyl succinic acid, 2-dicarboxylic acid, One or more selected from the group consisting of fumaric acid and anhydrides or derivatives thereof can be used. More specifically, the substance is maleic acid, itaconic acid, citraconic acid, acrylic acid, methacrylic acid, allyl succinic acid, 2-dicarboxylic acid, maleic acid, fumaric acid, diethyl maleate, dimethyl maleate, alkenyl succinic acid, cis- Selected from the group consisting of 1,2,3,6-tetrahydrophthalic acid, 4-methyl-1,2,3,6-tetrahydrophthalic acid, 4-methyl-4-cyclohexene-1, and anhydrides thereof desirable.

Preferred acid-modified rubber elastomers of the present invention are rubbers prepared from unsaturated monomers selected from the group consisting of ethylene propylene copolymers, ethylene propylene diene copolymers, styrene ethylene butadiene styrene copolymers, styrene butadiene styrene copolymers and ethylene ethyl acrylate copolymers. 100 parts by weight of an elastomer is included in a compound grafted with 0.5 to 5 parts by weight of α, β-unsaturated carboxylic acid, anhydride thereof and derivative thereof.

In particular, an aromatic vinyl copolymer is used as an important additive in the polyamide resin composition of the present invention, and its content is characterized by using an aromatic vinyl copolymer in an amount of 2 to 8% by weight based on the total composition. When the content of the aromatic vinyl copolymer is less than 2% by weight, the effects of dimensional stability and heat resistance are insignificant. When the content of the aromatic vinyl copolymer exceeds 8% by weight, the viscosity increases during melt kneading, the appearance of the surface of the product is poor, and the cost increases. This is not desirable because of the disadvantages.

In addition, the aromatic vinyl copolymer is a copolymer obtained by grafting the α, β-unsaturated carboxylic acid, its anhydride and derivatives thereof with a main chain of an aromatic vinyl monomer and polyphenylene maleimide represented by the following formula (1): it means.

[Formula 1]

Wherein Ar is aromatic phenyl.

That is, in general, since the polyphenylene maleimide alone is difficult to use, the present invention is used by copolymerizing an aromatic vinyl monomer compound.

In other words, since the aromatic vinyl copolymer is incompatible with the polyamide resin, the aromatic vinyl copolymer of the present invention is α.β based on 100 parts by weight of a copolymer composed of an aromatic vinyl monomer, polyphenylmaleimide, and a compound. -Unsaturated carboxylic acid, its anhydride or derivative thereof is grafted 0.5 to 2 parts by weight. At this time, when the content of α.β-unsaturated carboxylic acid, its anhydride or derivatives thereof is less than 0.5 parts by weight, compatibility with the polyamide resin is lowered, resulting in a decrease in impact resistance and rigidity. Although it is excellent in performance, it causes a problem of kneading due to a sudden increase in viscosity and a lot of gas generated during molding in the final composition, such as problems such as flow marks and silver bath on the surface of the product is undesirable.

The number average molecular weight of the aromatic vinyl copolymer of the present invention is 80,000 to 200,000. When the number average molecular weight of the aromatic vinyl copolymer is less than 80,000, the impact strength and bending modulus effect is inadequate, and in the case of more than 200,000, problems occur during melt kneading with too high viscosity.

In addition, the content of any one of the aromatic vinyl monomer and polyphenylene maleimide should be less than 40% by weight. Therefore, these can be mixed and used in the weight ratio of 60: 40-60: 40. If phenylmaleimide is less than 40% by weight, it may cause heat resistance deterioration, poor degree of polymerization, and poor impact resistance.If it exceeds 60% by weight, the cost increases, making it difficult to knead with high viscosity. Problems arise and are undesirable.

The aromatic vinyl monomer compounds to be copolymerized include styrene, polystyrene, α-methylstyrene, methylstyrene, vinyl xylene, monochlorostyrene, dichlorostyrene, monobromostyrene, dibromostyrene, pt-butylstyrene, ethylstyrene vinylnaphthalene, And o-methylstyrene may be used alone or in combination of two or more thereof. Preferably, the aromatic vinyl monomer compound uses polystyrene alone.

Representative examples of the α.β-unsaturated carboxylic acid, its anhydride or derivatives thereof include maleic acid, itaconic acid, citraconic acid, acrylic acid, methacrylic acid, allyl succinic acid, 2-dicarboxylic acid, maleic acid, fumaric acid, maleic acid di Ethyl, dimethyl maleate, alkenyl succinic acid, cis-1,2,3,6-tetrahydrophthalic acid, 4-methyl-1,2,3,6-tetrahydrophthalic acid, 4-methyl-4-cyclohexene-1, And anhydrides thereof, and maleic anhydride is preferably used.

In the present invention, preferred examples of the aromatic vinyl copolymer include those in which 0.5 to 2 parts by weight of maleic anhydride are grafted to 100 parts by weight of polystyrene and phenylmaleimide (1: 1).

Moreover, this invention can provide the polyamide resin molded article containing the polyamide resin composition which has the said characteristic.

The plastic part obtained by the composition of the present invention can satisfy the required physical properties of the functional and emotional aspects at the same time.

In the case of the present invention, one example of the use that can meet the object of the invention is an engine part of an automobile, which is suitable for wide, long and large thin film products, such as air intake manifolds and cylinder head covers. Suitable for Timing Belt Cover, Pen / Shroud, Engine Cover, Roof Rack, Carrier Parts of Front End Module, etc. In the case of industrial use, it is possible to provide an optimum resin for chain parts and chair parts.

As described above, the polyamide resin composition according to the present invention includes glass fiber, acid-modified rubber elastomer, and aromatic vinyl copolymer in a specific content range, and has excellent mechanical modulus of flexural modulus and impact strength, and measures of heat resistance. It is effective in providing a composition having excellent tearing temperature and excellent appearance characteristics, which is the quality of sensitivity after molding the product.

Hereinafter, preferred examples are provided to help understanding of the present invention, but the following examples are merely to illustrate the present invention, and the scope of the present invention is not limited by the following examples.

EXAMPLE

A twin screw extruder was used to prepare the inorganic reinforced polyamide resin composition of the present invention. At this time, the cylinder barrel is prepared at a temperature of 275 to 285 ℃ (245 ℃ to 255 ℃ in the case of nylon 6), in order to maximize the physical properties of the resin composition by using an extruder having three inlet, the primary inlet and polyamide resin An aromatic vinyl copolymer was added, an acid-modified rubber elastomer was injected into the secondary inlet, and glass fibers were introduced into the tertiary inlet. In particular, the tertiary inlet was used as close to the discharge part of the extruder as possible, so as to minimize the breakage of the glass fiber by the shear of the screw in the extruder. In addition, to minimize the residence time as part of maximizing the properties of the composition during melt kneading, a pressure reducing device called vent (Vent) is installed near the third inlet and outlet, and reduced pressure to 150 mmHg or less to perform a more effective process It was made.

Examples and Comparative Examples were carried out as follows, the composition of the resin prepared according to the evaluation of the respective physical properties based on the following evaluation criteria.

* Flexural modulus: measured after fabricating 1/8 inch specimens in accordance with ASTM D790, the value less than 40,000 kg / cm ² was determined to be defective.

* Impact strength: Izod Notched impact strength was measured at room temperature with 1/4 inch specimen according to ASTM D256 and 13 kg · cm / cm. Less than judged bad.

* Mold shrinkage: After making 100 mm diameter specimens in accordance with ASTM D960, leaving the specimens for 48 hours at room temperature and 50% absolute humidity, and evaluating the mold shrinkage in the flow direction centered on the gate (0.8%). The excess was judged to be defective.

* Heat deflection temperature: Measured after fabricating 1/4 inch specimen according to ASTM D648, the value less than 190 ℃ at 4.6kg / cm ² load was determined as bad.

* Product surface: Mold temperature was controlled at room temperature with a mold force of 150 tons Nisisa injection machine for a test cavity of 100 mm in width, 300 mm in length, and 3.0 mm in thickness. In addition, at the injection temperature, the polyamide 6 was set at 245 ° C and the polyamide 66 at 275 ° C. The first and second injection pressures without holding pressure were 60 bar, 40 bar, injection time 3 seconds, and cooling time 10 seconds, respectively. The test specimen was prepared by molding at an injection rate of 30% at first, 40% at second, 45% at third, and 40% at fourth. For the test piece, the surface of the gate and the end of the surface were visually observed using a microscope of x1000, and judged as good or bad.

Examples 1-14

Next, each component was melt-kneaded in a twin screw extruder heated to 280 ° C (250 ° C for nylon 6) with a composition as shown in Table 1, and then made into a chip state, using a 90 ° C dehumidifying dryer for 5 hours. After drying, each specimen was produced at the same temperature as melt kneading using a heated screw-type injection molding machine. Each specimen thus prepared was subjected to physical property evaluation by the evaluation method as described above, and the measurement results are shown in Table 2 below.

division Polyamide 66 (% by weight) Polyamide 6 (% by weight) Fiberglass (wt%) Acid-modified rubber elastomer (wt%) Aromatic vinyl copolymer (% by weight) Example 1 77 - 15 3 TPE 1 5 TPS 1 Example 2 63 - 20 5 TPE 2 2 TPS 2 Example 3 61 - 30 5 TPE 3 4 TPS 3 Example 4 57 - 30 7 TPE 2 6 TPS 2 Example 5 - 62 25 7 TPE 1 6 TPS 1 Example 6 - 54 30 10 TPE 3 6 TPS 3 Example 7 - 70 15 7 TPE 1 8 TPS 2 Example 8 - 64 30 5 TPE 3 3 TPS 2 Example 9 67 - 20 5 TPE 1 6 TPS 1 Example 10 51 - 40 3 TPE 2 6 TPS 3 Example 11 52 - 30 10 TPE 3 8 TPS 2 Example 12 - 58 30 7 TPE 1 5 TPS 3 Example 13 - 63 25 7 TPE 2 5 TPS 1 Example 14 - 50 40 5 TPE 3 5 TPS 2

Note) In Table 1 above,

* TPE1: 1 part by weight of maleic anhydride, 100 parts by weight of styrene ethylene butadiene styrene rubber elastomer

* TPE2: 2.5 parts by weight of maleic anhydride, 100 parts by weight of styrene ethylene butadiene styrene rubber elastomer

* TPE3: 4 parts by weight of maleic anhydride, 100 parts by weight of styrene ethylene butadiene styrene rubber elastomer

* TPS1: 1 part by weight of maleic anhydride, 100 parts by weight of polystyrene / phenylmaleimide graft copolymer

* TPS2: 1.5 parts by weight of maleic anhydride, 100 parts by weight of polystyrene / phenylmaleimide graft copolymer

* TPS3: 2 parts by weight of maleic anhydride, 100 parts by weight of polystyrene / phenylmaleimide graft copolymer

division Flexural Modulus (Kg / ㎠) Impact Strength (Kgcm / cm) Mold Shrinkage (%) Heat Deflection Temperature (℃) Surface (Good-O Bad-X) Example 1 44,100 14 0.75 231 O Example 2 63,300 16 0.63 237 O Example 3 78,000 17.5 0.50 243 O Example 4 75,500 20.5 0.51 242 O Example 5 68,000 18 0.53 194 O Example 6 71,500 22.5 0.49 199 O Example 7 44,600 20 0.71 192 O Example 8 80,500 18 0.56 201 O Example 9 60,900 17.5 0.62 237 O Example 10 98,100 16 0.33 250 O Example 11 70,500 22 0.37 243 O Example 12 74,200 20.5 0.41 205 O Example 13 67,300 19.5 0.53 197 O Example 14 94,200 22 0.31 207 O

Comparative example  1 to 14

The polyamide resin composition was prepared in the same manner as in Examples 1 to 14, except that the composition was shown in Table 3, and each test specimen was prepared in the same manner to evaluate physical properties. The measurement results are shown in Table 4 below.

division Polyamide 66 (% by weight) Polyamide 6 (% by weight) Fiberglass (wt%) Acid-modified rubber elastomer (wt%) Aromatic vinyl copolymer (% by weight) Comparative Example 1 41 - 45 7 TPE 1 7 TPS 1 Comparative Example 2 76 - 10 7 TPE 2 7 TPS 2 Comparative Example 3 - 52 30 12 TPE 3 6 TPS 2 Comparative Example 4 62 - 30 2 TPE 2 6 TPS 3 Comparative Example 5 - 53 30 7 TPE 1 10 TPS 1 Comparative Example 6 - 62 30 7 TPE 3 One TPS 2 Comparative Example 7 57 - 30 7 TPE 4 6 TPS 1 Comparative Example 8 - 57 30 7 TPE 5 6 TPS 2 Comparative Example 9 - 64 25 6 TPE 2 5 TPS 4 Comparative Example 10 64 - 25 6 TPE 1 5 TPS 5

Note) In Table 3 above,

* TPE1: 1 part by weight of maleic anhydride, 100 parts by weight of styrene ethylene butadiene styrene rubber elastomer

* TPE2: 2.5 parts by weight of maleic anhydride, 100 parts by weight of styrene ethylene butadiene styrene rubber elastomer

* TPE3: 4 parts by weight of maleic anhydride, 100 parts by weight of styrene ethylene butadiene styrene rubber elastomer

* TPE4: 0.3 parts by weight of maleic anhydride, 100 parts by weight of styrene ethylene butadiene styrene rubber elastomer

* TPE5: 6 parts by weight of maleic anhydride, 100 parts by weight of styrene ethylene butadiene styrene rubber elastomer

* TPS1: 1 part by weight of maleic anhydride, 100 parts by weight of polystyrene / phenylmaleimide graft copolymer

* TPS2: 1.5 parts by weight of maleic anhydride, 100 parts by weight of polystyrene / phenylmaleimide graft copolymer

* TPS3: 2 parts by weight of maleic anhydride, 100 parts by weight of polystyrene / phenylmaleimide graft copolymer

* TPS4: 0.3 parts by weight of maleic anhydride, 100 parts by weight of polystyrene / phenylmaleimide graft copolymer

* TPS5: 2.5 parts by weight of maleic anhydride, 100 parts by weight of polystyrene / phenylmaleimide graft copolymer

division Flexural Modulus (Kg / ㎠) Impact Strength (Kgcm / cm) Mold Shrinkage (%) Heat Deflection Temperature (℃) Surface (Good-O Bad-X) Comparative Example 1 99,800 21.5 0.19 251 X Comparative Example 2 38,000 12 1.00 204 O Comparative Example 3 59,000 25 0.91 189 X Comparative Example 4 78,500 10.5 0.48 249 O Comparative Example 5 81,200 12.5 0.46 187 X Comparative Example 6 75,300 18 0.95 188 X Comparative Example 7 77,000 11 0.77 241 O Comparative Example 8 80,400 10.5 0.83 198 X Comparative Example 9 70,500 12 0.95 188 O Comparative Example 10 85,200 16.5 0.54 236 X

As shown in Tables 1 to 4, Examples 1 to 14 of the present invention include the polyamide resin, the glass fiber and the acid-modified polyolefin which is an acid-modified rubber elastomer, and the acid-modified rubber elastomer at a specific composition ratio, and therefore, the graphs of the components Compared with Comparative Examples 1 to 10, the degree and content ratio of the sheet out of the range of the present invention can be seen to have excellent properties at the same time in terms of overall physical properties such as flexural modulus, impact strength, mold shrinkage and heat deformation temperature, molded product surface.

Although the preferred embodiments of the present invention have been described above, the present invention is not limited thereto, and various modifications and changes can be made within the scope of the claims and the detailed description of the invention and the accompanying drawings. Naturally, it belongs to the scope of the invention.

The polyamide resin composition of the present invention is excellent in physical properties and surface appearance such as flexural modulus, impact strength, molding shrinkage rate, heat deformation temperature, etc. can be used as various parts of automobiles, industrial chain parts or chair parts.

Claims (15)

The impact strength according to ASTM evaluation method D256 is 13 kgcm / cm or more, Flexural modulus by ASTM evaluation method D790 is 40,000 kg / cm 2 or more, Mold shrinkage by ASTM evaluation method D960 is 0.8% or less, Polyamide resin composition to have a physical deformation temperature of 190 ° C or more by the ASTM evaluation method D648. According to claim 1, wherein the composition has an impact strength of 13 to 25 kg · cm / cm by ASTM evaluation method D256, flexural modulus of 40,000 to 100,000 kg / cm 2 by ASTM evaluation method D790, molding shrinkage 0.8 in the flow direction by ASTM evaluation method D960 To 0.4%, and the polyamide resin composition to have a physical deformation temperature of 190 to 255 ° C. according to ASTM Evaluation Method D648. The method of claim 1, wherein the composition (a) 50 to 80% by weight of polyamide resin, (b) 15 to 40 weight percent of glass fibers, (c) 3 to 10% by weight of an acid-modified rubber elastomer in which 0.5 to 5 parts by weight of α, β-unsaturated carboxylic acid, anhydride thereof or derivative thereof is grafted to 100 parts by weight of rubber elastomer, and (d) 2 to 8% by weight of an aromatic vinyl copolymer in which 0.5 to 2 parts by weight of α, β-unsaturated carboxylic acid or anhydride is grafted to 100 parts by weight of the aromatic vinyl monomer and polyphenylmaleimide, which are the main chains; Polyamide resin composition comprising a. The polyamide resin composition according to claim 3, wherein the polyamide resin has a relative viscosity of 2.1 to 3.5 (20 DEG C, based on a solution of 1 g of polymer in 100 mL of 96% sulfuric acid). The polyamide resin composition of claim 3, wherein the polyamide resin is selected from the group consisting of nylon 6, nylon 66, and mixtures thereof. The polyamide resin composition according to claim 3, wherein the glass fibers have an average length of 3 to 6 mm and an average diameter of 10 to 13 m. The polyamide resin composition according to claim 3, wherein the rubber elastomer is prepared from at least one unsaturated monomer selected from the group consisting of α-olefins, acrylic acid and its derivatives, aromatic vinyl monomers, vinyl cyanide monomers and diene monomers. . According to claim 3, wherein the α, β-unsaturated carboxylic acid or anhydride is maleic acid, itaconic acid, citraconic acid, acrylic acid, methacrylic acid, allyl succinic acid, 2-dicarboxylic acid, maleic acid, fumaric acid, diethyl maleate Dimethyl maleate, alkenyl succinic acid, cis-1,2,3,6-tetrahydrophthalic acid, 4-methyl-1,2,3,6-tetrahydrophthalic acid, 4-methyl-4-cyclohexene-1, and Polyamide resin composition which is at least one selected from the group consisting of these anhydrides. The method of claim 3, wherein the acid-modified rubber elastomer is from an unsaturated monomer selected from the group consisting of ethylene propylene copolymer, ethylene propylene diene copolymer, styrene ethylene butadiene styrene copolymer, styrene butadiene styrene copolymer and ethylene ethyl acrylate copolymer A polyamide resin composition comprising a compound obtained by grafting 100 parts by weight of the rubber elastomer to be prepared at 0.5 to 5 parts by weight of an α, β-unsaturated carboxylic acid, anhydride thereof and derivatives thereof. The method of claim 3, wherein the aromatic vinyl monomer is styrene, polystyrene, α-methylstyrene, methylstyrene, vinyl xylene, monochlorostyrene, dichlorostyrene, monobromostyrene, dibromostyrene, pt-butylstyrene, ethyl styrene Polyamide resin composition which is at least one selected from vinyl naphthalene and o-methylstyrene. The polyamide resin composition according to claim 10, wherein the aromatic vinyl monomer is polystyrene. The polyamide resin composition of claim 3, wherein the aromatic vinyl copolymer has a number average molecular weight of 80,000 to 200,000. The polyamide resin composition according to claim 3, wherein the aromatic vinyl copolymer is a polystyrene / phenylmaleimide (1: 1) copolymer in which 0.5 to 2 parts by weight of maleic anhydride is grafted to 100 parts by weight of polystyrene / phenylmaleimide. A polyamide resin molded article comprising the polyamide resin composition according to any one of claims 1 to 13. 15. The molded article according to claim 14, wherein the molded article includes an air intake manifold of a vehicle, a cylinder head cover timing belt cover, a pen / shroud, an engine cover, a roof rack, a carrier part of a front end module, an industrial chain part or a chair part. Polyamide resin molded article.