KR101139827B1 - Poly amide-ABS Thermoplastic Resin - Google Patents

Abstract

The present invention relates to a thermoplastic resin composition capable of molding various products having excellent moldability, good mechanical properties, excellent fluidity, and complex structures.

The thermoplastic resin composition according to the present invention is polyamide 20 to 48%, acrylonitrile-butadiene-styrene copolymer 50 to 68%, modified aromatic vinyl compound / maleimide copolymer 1 to 15%, and low viscosity maleated 1 to 30% of an ethylene-propylene-diene compound copolymer.

 The thermoplastic resin composition according to the present invention provides a thermoplastic ABS-polyamide resin composition for automobile interior and exterior materials which is excellent in fluidity and characterized by high impact properties.

Description

Polyamide- (acrylonitrile-butadiene-styrene) thermoplastic resin composition {Poly amide-ABS Thermoplastic Resin}

The present invention relates to a thermoplastic resin composition capable of molding various products having excellent moldability, good mechanical properties, excellent fluidity, and complex structures.

Polyamide resin is obtained by ring-opening polymerization of caprolactam, which is commonly known, and has excellent heat resistance, mechanical properties, and chemical resistance, and can easily reinforce inorganic materials such as glass fiber, carbon fiber, and talc, and thus can express very high strength. have. However, since the impact resistance is small and the crystalline resin has a large molding shrinkage rate, there is a problem in that deformation easily occurs.

On the other hand, acrylonitrile-butadiene-styrene copolymer has excellent secondary workability such as molding processability, impact resistance, heat resistance, coating, plating, etc. by changing the structure and controlling the content of the composition by the manufacturing method, and it is dimensional stability because it is an amorphous resin. great. However, since the rigidity and heat resistance are inferior, they are used in the form of impact reinforcing materials alone or blended with engineering plastic resins in industries such as electrical, electronics and automobiles.

Accordingly, attempts have been made to harmonize the properties of polyamide with the processability of ABS. However, polyamide resins and ABS resins do not have good compatibility, but often have adverse effects. Accordingly, development of various compatibilizers has been made.

For example, U.S. Pat.No. 5,248,726 uses acrylonitrile-butadiene-styrene copolymer (ABS) resins and carboxylated nitrile rubbers in polyamide resins to compensate for dimensional stability and impact resistance. This is not very high, and if the impact resistance is high, there is a problem that the heat resistance is poor.

In another U.S. Patent No. 5,010,138, a compatibilizer made by extruding a polyamide resin and an α-methylstyrene / acrylonitrile / t-butylacrylate copolymer is used to form a polyamide resin and styrene-acrylonitrile. It is added to the coalescing (SAN) and ABS resin to improve the impact resistance and dimensional stability, but has a disadvantage in terms of process because the heat resistance is poor and the two-step extrusion process must be performed.

Another U.S. Patent No. 5,202,379 has a high impact from low temperature to room temperature by mixing styrene / N-phenylmaleimide copolymer and styrene / acrylonitrile / methyl methacrylate copolymer in polyamide resin and ABS resin. Although strength and dimensional stability are expressed, the strength, elastic modulus and heat resistance are too low overall.

In addition, Korean Patent No. 434640, issued to Rhodia Polyamide Co., Ltd., contains a copolymer of a modified aromatic vinyl compound / maleimide containing polyamide as a main material and a modified EPDM elastomer with high butadiene content to improve shrinkage after molding. A method of kneading ABS resin is disclosed, and Korean Patent No. 830133, issued to Espolymer Co., Ltd., uses a maleated ethylene-octene copolymer together with a modified aromatic vinyl compound / maleimide copolymer in a polyamide and ABS resin mixture. It suggests a way to do it.

However, when the above compatibilizer is used, the physical properties are improved, but the melt flowability of the resin is lowered by the maleic hydride having a reactive group, and thus the moldability is remarkably lowered. As a result, products with complex shapes could not be manufactured.

An object of the present invention is to propose a new method that can prevent the degradation of melt flow due to maleimide while increasing the kneading property between polyamide and ABS resin using a compatibilizer having a maleimide group.

Another object of the present invention is to provide a highly flexible polyamide-ABS resin that can mold a product having a complicated shape.

Still another object of the present invention is to provide a molded article of a complicated shape made of a highly flexible polyamide-ABS resin.

In order to achieve the above object, the resin composition according to the present invention, the thermoplastic resin composition according to the present invention is 20 to 48% polyamide, acrylonitrile-butadiene-styrene copolymer 50 to 68%, modified aromatic vinyl compound It is characterized by including 1-15% of maleimide copolymers, and 1-30% of a low viscosity maleated ethylene-propylene-diene compound copolymer.

In the present invention, the resin composition is used for automotive parts requiring high fluidity, and the impact resistance and surface gas problems required during molding are solved, and the thermal stability is improved.

Examples of the polyamide resin (A) that can be used in the present invention include polyamides obtained by ring-opening polymerization of commonly known lactams such as ε-caprolactam and ω-dodecaractam, aminocapronic acid, 11-aminoundecanoic acid, Polyamides obtained from amino acids such as 12-aminododecanoic acid, ethylenediamine, tetramethylenediamine, hexamethylenediamine, undecamethylenediamine, dodecamethylenediamine, 2,2,4-trimethylhexamethylenediamine, 2, 4,4-trimethylhexamethylenediamine, 5-methylnonahexamethylenediamine, metaxylenediamine, paraxylenediamine, 1,3-bisaminomethylcyclohexane, 1,4-bisaminomethylcyclohexane, 1-amino-3 -Aminomethyl-3,5,5-trimethylcyclohexane, bis (4-aminocyclohexyl) methane, bis (4-methyl-4-aminocyclohexyl) methane, 2,2-bis (4-aminocyclohexyl) Propane, bis (aminoph Aliphatic, cycloaliphatic and aromatic diamines, such as piperazine and aminoethylpiperazine, adipic acid, subberic acid, sebacic acid, azelaic acid, terephthalic acid, isophthalic acid, 2-chloroterephthalic acid, 2-methylterephthalic acid, 5-methyl Polyamides obtained from aliphatic, cycloaliphatic and aromatic dicarboxylic acids such as isophthalic acid and the like, copolymers of such polyamides and mixtures thereof, in particular aliphatic polyamides, aromatic polyamides such as polyamide-6, Polyamide-66, polyamide-610, polyamide-11, polyamide-12, terephthalic acid and isophthalic acid polyamides, and copolymers thereof and mixtures thereof. Commercially, polyamide-6, polyamide-66, or a polyamide 66/6 copolymer which is a copolymer thereof and the like can be used, and it is preferable to use them separately according to the characteristics according to the required physical properties.

In the present invention, the polyamide resin is preferably polyamide-6 having a melting point of 220 ° C. so as to improve the fluidity of the final resin, and it is preferable to use a 2.4-3.0 polyamide resin having a Relative Viscosity.

 In the present invention, the polyamide resin is preferably used in the resin composition 20 to 48% by weight. If the content is less than 20% by weight, it is difficult to obtain mechanical properties and it is difficult to maintain the intrinsic properties of the polyamide. In addition, when the content of the polyamide is increased, the content of the ABS resin having good moldability is relatively low, and thus high fluidity cannot be secured.

In the present invention, the acrylonitrile-butadiene-styrene copolymer is a product in which butadiene-based rubber is dispersed in a matrix composed of styrene and acrylonitrile, and prepared by various methods such as bulk polymerization, emulsion polymerization and sus polymerization. It can be purchased and commercially available.

In the present invention, the acrylonitrile-butadiene-styrene copolymer is preferably included at least 50% by weight, more preferably 55-65% by weight to provide sufficient fluidity to the resin. When the content of the acrylonitrile-butadiene-styrene copolymer is low, moldability is low, and a product of a complicated form cannot be molded, and when the content is too high, physical properties are degraded.

In one embodiment of the present invention, the acrylonitrile-butadiene-styrene copolymer is a graft copolymer of styrene and acrylonitrile graft polymer and styrene and acrylonitrile copolymer blended in a butadiene rubber, rubber It is preferable to use a product whose content is adjusted to 15-28%.

In the present invention, the modified aromatic vinyl compound / maleimide copolymer is a compatibilizer used to increase the kneading resistance and heat resistance impact resistance of the resin composition, the modified aromatic vinyl compound / maleimide copolymer content in the resin composition Preference is given to using 1-15% by weight, more preferably 2-10% by weight, most preferably 3-7% by weight. When the amount of the modified aromatic vinyl compound / maleimide copolymer is small, there is no compatibility between the polyamide resin and the ABS resin, and when used in an excessive amount, there is no improvement in compatibility, but rather the physical properties are lowered. .

In the present invention, the modified aromatic vinyl compound / maleimide copolymer is a copolymer of an aromatic vinyl compound, maleimide, unsaturated dicarboxylic acid or unsaturated dicarboxylic anhydride, preferably aromatic vinyl compound 30 to 80 Weight percent, 19 to 69 weight percent maleimide, and 1 to 10 weight percent unsaturated dicarboxylic acid or unsaturated dicarboxylic anhydride.

In the practice of the present invention, the aromatic vinyl compound contains styrene, α-methylstyrene, p-methylstyrene, etc. as a main component, and may include a small amount of other copolymerizable vinyl compounds. The unsaturated dicarboxylic acid or unsaturated dicarboxylic anhydride may be maleic anhydride, methyl maleic anhydride, 1,2-dimethylmaleic anhydride, ethyl maleic anhydride, phenylmaleic anhydride, acrylic acid, methacrylic acid and their It can be selected from the group consisting of mixtures. As the monomer copolymerizable with the aromatic vinyl compound, the vinyl compound may be methyl (meth) acrylate, ethyl (meth) acrylate, butyl (meth) acrylate, hexyl (meth) acrylate, cyclohexyl (meth) acrylate, Decyl (meth) acrylate, octadecyl (meth) acrylate, hydroxyethyl (meth) acrylate, methoxyethyl (meth) acrylate, glycidyl (meth) acrylate, and the like.

In the practice of the present invention, the modified aromatic vinyl-based compound / maleimide copolymer may be prepared by a known method or commercially available and used, preferably a maleic anhydride grafted in the range of 1 to 10% by weight Good to do. When the amount of the maleic hydride is small, the compatibility may be lowered, and when the amount is large, the fluidity of the resin may be lowered and gelation may occur.

In the present invention, the maleated ethylene-propylene-diene compound copolymer rubber is a small amount of maleic anhydride chemically bonded, the ethylene group content of 30 to 75% by weight, the propylene group content of 20 to 50% by weight of the diene As a copolymer having a compound content of 0 to 20% by weight, it may be prepared by synthesis by a known method, or commercially available.

In the present invention, the maleated ethylene-propylene-diene compound copolymer rubber reinforces the impact property of the resin composition, while using a low-viscosity product to prevent the fluidity decrease caused by the maleimide contained in the compatibilizer It is preferable.

In the practice of the present invention, the maleated ethylene-propylene-diene compound copolymer is 0.1-10% by weight of maleic ene hydride.

In a preferred embodiment of the present invention, the viscosity of the rubber is preferably 10-60 (1 + 4,100 ° C.), and when the viscosity of the rubber becomes too large, the fluidity of the overall resin decreases remarkably, and the viscosity of the rubber is too small. Ground physical properties will be degraded.

In the present invention, the maleated ethylene-propylene-diene compound copolymer rubber preferably has a content of 0.5-30% by weight in the resin composition, more preferably 1-20% by weight, most preferably 2 -10 weight percent. If the content of ethylene-propylene rubber in the resin composition is 0.5% or less, the impact reinforcing effect is not expressed, and in the 30% or more, the modulus such as modulus decreases and becomes weak.

In the practice of the present invention, the maleated ethylene-propylene rubber may be commercially available and available.

In the present invention, in addition to the above components, additives such as stabilizers, pigments, plasticizers, ultraviolet absorbers, lubricants, fillers and the like which are commonly used may be added.

The resin composition of the present invention can be produced by blending a resin composition using a general mixed melt processing apparatus such as a Banbury mixer or an extruder by blending.

In this way, the resin composition having excellent extrusion and injection moldability can be obtained by mixing the appropriate ratio in consideration of composition molecular weight difference control and compatibility with each component.

As described above, the present invention relates to a thermoplastic resin composition having excellent moldability and good mechanical properties. The present invention relates to a polyamide and an acrylonitrile-butadiene-styrene copolymer content to adjust the balance of heat deformation temperature and mechanical strength. In addition, a low viscosity resin was used to improve moldability. Part of the impact strength deterioration property due to the use of low viscosity has developed a resin composition having excellent impact properties and excellent moldability by using a maleated ethylene-propylene-diene compound copolymer.

Hereinafter, the present invention will be described in detail with reference to Examples, but the present invention is not limited to Examples.

Examples 1 to 2

After mixing sufficiently with a small tumbler mixer for uniform mixing with the composition ratio as shown in Table 1, the extrusion temperature was changed to 220 ~ 250 ℃ in a twin screw extruder with φ = 25mm, cooled, solidified, and pelletized. After 4 hours of drying in a maintained hot air dryer, the injection temperature was changed to 230-250 ℃ in a 160-ton injection machine, and the dried pellet was molded to form a joining line at a mold temperature of 65 ℃ to prepare a mechanical strength test specimen. The melt flow index was also measured to examine the melt flow.

Comparative Examples 1 to 7

Specimens were prepared in the same manner as in the compositions and compositions described in Table 1 above.

Test Example 1

After leaving the specimens prepared according to Examples 1 to 5 and Comparative Examples 1 to 5 for 24 hours, physical properties were measured according to the following method, and pellets were measured for fluidity after drying, and the results are shown in Table 1. .

<Test method>

(1) Tensile strength (kgf / cm ² )

The test was conducted using a tensile test equipment according to the test method of ASTM D638.

(2) Izod impact strength 6.4mm (kgf? Cm / cm)

Tests were made using an Izod impactor using the ASTM D256 method. Notched Izod Impact Strength was measured with a 6.4 mm specimen thickness.

(3) Heat deflection temperature (℃)

ASTM D648 method was used and measured under 18.6 kgf / cm ² load.

(4) Meltflow Index (g / 10min)

ASTM D1238 method was used, and measured at a load of 230 ° C. and 10 kg.

The fluidity index was determined to be more than 30 based on actual experiments and field experiences, which is advantageous for injection molding.

(5) Surface of molded article (Gas mark)

The surface state of the speaker grill molded product was observed during molding at 250 ° C.

     Item Example Comparative example One 2 One 2 3 4 5 6 7 Composition
(weight%)


A Midpoint 40 50 40 50 Low viscosity 40 40 40 50 40 B High viscosity Midpoint 60 50 60 50 Low viscosity 60 60 60 50 60 Composition
(PHR) C 5 5 5 5 5 5 5 5 5 D 5 3 characteristic The tensile strength 430 460 470 450 470 450 470 470 450 Izod
Impact strength 25 15 19 21 18 20 10 25 27 Heat deformation
Temperature 84 85 88 85 89 86 87 90 88 Melt flow
Index index 41 42 30 33 30 33 40 20 25 Surface of moldings
(Gas mark) Good Good Slightly poor Slightly poor Slightly poor Slight Good Bad Bad

(week)

A) Polyamide resin (medium viscosity: RV 2.8 ± 0.03, low viscosity: RV 2.45 ± 0.03)

B) acrylonitrile butadiene styrene copolymer

ABS Mid-Point, Kumho Petrochemical ABS740, Acrylonitrile 20% by weight, Butadiene 18% by weight, Styrene 62% by weight, MI 25

ABS low viscosity, Kumho Petrochemical ABS780, 10 wt% acrylonitrile, 16 wt% butadiene, 74 wt% styrene. MI 45

C) Modified Aromatic Vinyl Compound / Maleimide Copolymer

Copolymer consisting of 46% by weight of styrene, 53% by weight of N-phenylmaleimide and 1.0% by weight of maleic anhydride (Polyimilex® PSX-371, manufactured by Nihon Shokubai).

D) Maleated Ethylene-Propylene-Diene Compound Copolymer:

Pattern viscosity 20 (1 + 4,100 ° C.), ethylene 40 wt%, propylene 59 wt%, butadiene 0 wt%, maleimide 1 wt%

In Examples 1 and 2, by adding a maleated ethylene-propylene-diene compound copolymer to a compound of low viscosity nylon and low viscosity ABS, the impact value can be satisfied and the moldability can be obtained at the same time.

Comparative Examples 1 and 2 correspond to the case of compounding a medium viscosity nylon and a low viscosity ABS.

The mechanical strength was good and a slight degree of gas mark was generated.

Comparative Examples 3-4 correspond to the case where the low viscosity nylon and the medium viscosity ABS were compounded.

Impact strength and thermal deformation temperature fluidity are similar to those of Comparative Examples 1 and 2. Slightly insufficient gas mark was generated.

Comparative Example 5 is a compounding of low viscosity nylon and low viscosity ABS, it can be seen that the impact strength, heat deformation temperature, etc., but exhibits more than the physical properties required by the vehicle except the impact strength value. In particular, the impact strength needs to be improved as the value of 12 or less is used.

On the other hand, the gas mark on the surface of the molded article is much improved, it turns out to be suitable for use in terms of formability.

Comparative Examples 6 to 7 correspond to the case of compounding a medium-weight nylon and a medium-weight ABS, which satisfies all mechanical properties but are not satisfied with a molded article requiring high flow such as an automobile speaker grill. In addition, it can be seen that as the nylon content increases, the tensile strength and heat deflection temperature decrease.

As can be seen from the table above, low viscosity nylon should be used for resins that require high fluidity, such as the speaker grille surface, and it is also recommended to use a maleic ethylene-propylene-diene compound copolymer as a nylon impact modifier It is advantageous.

Claims (7)

20 to 48% polyamide having an average relative viscosity of 2.4 to 3.0, 50 to 68% of an acrylonitrile-butadiene-styrene copolymer having a rubber content of 15 to 28% by weight, and a modified aromatic vinyl compound / maleimide copolymer 1 to 15%, and 1-30% maleated ethylene-propylene-diene compound copolymer, characterized in that the flow index (MI) is 30 or more at 230 ℃, 10 kg load by ASTM D1238 method, characterized in that Composition. The high flow thermoplastic resin composition of claim 1, wherein the maleated ethylene-propylene-diene compound copolymer has a viscosity of 10-60 (1 + 4,100 ° C.). According to claim 2, wherein the maleated ethylene-propylene-diene compound copolymer is composed of 0.1-10% by weight maleic anhydride, 30-75% by weight ethylene, 20-50% by weight propylene, 0-20% by weight diene compound content A high flow thermoplastic resin composition, characterized in that the copolymer. delete The high flow thermoplastic resin composition according to claim 1, wherein the modified aromatic vinyl compound / maleimide copolymer is grafted with 1-10% maleic hydride. delete An injection molded product molded into the high flow thermoplastic resin composition according to any one of claims 1-3.