Thermoplastic resin composition and molded article manufactured therefrom

Abstract

The present invention relates to a thermoplastic resin composition and a molded article manufactured therefrom, the composition comprising: (A) 30-40 wt% of an acrylonitrile-butadiene-styrene graft copolymer comprising 50-70 wt% of a butadiene-based rubbery polymer having an average particle diameter of 250-450 nm; (B) 30-50 wt% of a first styrene-acrylonitrile copolymer having a weight average molecular weight of 250,000-350,000 g / mol and containing 0.6-1 wt% of oligomers; (C) 10-30 wt% of a second styrene-acrylonitrile copolymer having a weight average molecular weight of 100,000-150,000 g / mol and containing 0.5 wt% or less of oligomers; (D) 2-10 wt% of an α-methylstyrene-styrene-acrylonitrile copolymer; and (E) 1-5 wt% of an N-phenylmaleimide-styrene-maleic anhydride copolymer.

Description

Thermoplastic resin composition and molded article manufactured therefrom

[0001] It relates to a thermoplastic resin composition and a molded article manufactured therefrom.

[0002] Blow molding is a method of manufacturing a molded product by forming a parison by injection or extrusion and injecting air into it. Examples include extrusion blow molding, injection blow molding, and injection stretch blow molding.

[0003] Specifically, extrusion blow molding uses an extruder to melt resin, attach a die that can form a hollow shape like a hollow pipe to the end of the extruder to form a parison, and then the parison is lowered vertically into an open mold, the mold is closed to cut the parison, and then air is blown into the parison to produce a molded product of the desired shape.

[0004] Meanwhile, acrylonitrile-butadiene-styrene (ABS) resin is a widely used material for various office equipment, electrical and electronic components, and automotive interior and exterior materials due to its excellent properties, including impact resistance, chemical resistance, and moldability. Among these, automotive exterior materials, such as rear spoilers, are manufactured using blow molding.

[0005] ABS resin is used to manufacture various molded products through the blow molding process described above. However, due to the nature of the blow molding process, the parison is formed from a die that is vertically downward relative to the ground, causing gravity to cause the parison to sag. This can increase the defect rate due to thickness variation in the molded product and reduce process efficiency. Furthermore, if a large amount of volatile gas is generated from the molten resin during parison molding, the gas can deposit on the mold surface, degrading the appearance of the molded product.

[0006] Accordingly, a thermoplastic resin composition having fluidity suitable for blow molding and low volatile gas generation is required.

[0007] One embodiment provides a thermoplastic resin composition having excellent blow moldability and generating a low amount of volatile gas during the manufacture of a molded product.

[0008] Another embodiment provides a molded article manufactured from the thermoplastic resin composition.

[0009] According to one embodiment, a thermoplastic resin composition comprises: (A) 30 to 40 wt% of an acrylonitrile-butadiene-styrene graft copolymer (g-ABS) comprising 50 to 70 wt% of a butadiene-based rubbery polymer having an average particle diameter of 250 to 450 nm; (B) 30 to 50 wt% of a first styrene-acrylonitrile copolymer (SAN) having a weight average molecular weight of 250,000 to 350,000 g / mol and an oligomer content of 0.6 to 1 wt%; (C) 10 to 30 wt% of a second styrene-acrylonitrile copolymer (SAN) having a weight average molecular weight of 100,000 to 150,000 g / mol and an oligomer content of 0.5 wt% or less; (D) 2 to 10 wt% of alpha-methylstyrene-styrene-acrylonitrile copolymer (AMS-SAN); and (E) 1 to 5 wt% of N-phenyl maleimide-styrene-maleic anhydride copolymer (PMI-SM-MAH).

[0010] The above (A) acrylonitrile-butadiene-styrene graft copolymer may have a core-shell structure including a core made of a butadiene-based rubber polymer, and a shell formed by graft polymerizing acrylonitrile and styrene onto the core.

[0011] The above (B) first styrene-acrylonitrile copolymer may include 60 to 80 wt% of structural units derived from styrene and 20 to 40 wt% of structural units derived from acrylonitrile, based on the total weight of all structural units of the copolymer.

[0012] The above (C) second styrene-acrylonitrile copolymer may include 60 to 80 wt% of structural units derived from styrene and 20 to 40 wt% of structural units derived from acrylonitrile, based on the total weight of all structural units of the copolymer.

[0013] The above (D) alpha-methylstyrene-styrene-acrylonitrile copolymer may include 50 to 60 wt% of structural units derived from alpha-methylstyrene, 10 to 30 wt% of structural units derived from styrene, and 20 to 30 wt% of structural units derived from acrylonitrile, based on the total weight of all structural units of the copolymer.

[0014] The above (E) N-phenyl maleimide-styrene-maleic anhydride copolymer may include 20 to 60 wt% of structural units derived from N-phenyl maleimide, 20 to 75 wt% of structural units derived from styrene, and 1 to 10 wt% of structural units derived from maleic anhydride, based on the total weight of all structural units of the copolymer.

[0015] The glass transition temperature (Tg) of the above (E) N-phenyl maleimide-styrene-maleic anhydride copolymer may be 150 to 200°C.

[0016] The weight average molecular weight of the above (D) alpha-methylstyrene-styrene-acrylonitrile copolymer may be 50,000 to 300,000 g / mol.

[0017] The weight average molecular weight of the above (E) N-phenyl maleimide-styrene-maleic anhydride copolymer may be 100,000 to 300,000 g / mol.

[0018] The thermoplastic resin composition may further include at least one additive selected from among flame retardants, nucleating agents, coupling agents, glass fibers, plasticizers, lubricants, mineral fillers, antibacterial agents, release agents, heat stabilizers, antioxidants, ultraviolet stabilizers, pigments, dyes, and antistatic agents.

[0019] Another embodiment provides a molded article manufactured from the thermoplastic resin composition described above.

[0020] The above-mentioned molded product in the form of a pellet may have a melt-flow index of 3 to 5 g / 10 min as measured according to ASTM D1238 at 220°C and 10 kg.

[0021] When the above-mentioned molded product in the form of a pellet is fed into an extrusion blow molding machine set to a barrel temperature of 190 to 200°C and a screw rotation speed of 20 to 30 rpm to mold a parison having a diameter of 40 mm and a thickness of 2 mm, the time taken for the parison to separate from the die and begin to fall freely after the screw rotation speed is adjusted to 0 rpm when the length of the molded parison reaches 25 cm (hanging time) may exceed 150 seconds (sec).

[0022] The length of the formed parison until it separates from the die and begins to fall freely may be less than 300 mm.

[0023] When 4 g of the above-mentioned molded product in the form of pellets is placed in a Petri dish with a glass lid, placed on a hot plate at 250°C, heated for 2 hours, and then aged to room temperature, the amount of volatile gas generated measured from the residue remaining on the lid may be 2,100 ppm or less.

[0024] A thermoplastic resin composition according to one embodiment has excellent blow moldability and can reduce the amount of volatile gas generated during the manufacture of a molded product.

[0025] A molded product manufactured from a thermoplastic resin composition according to one embodiment can secure an excellent appearance.

[0026] FIG. 1 is a photograph of a parison molded with a thermoplastic resin composition according to Example 1 and Comparative Example 14 to measure the length of a freely falling parison when measuring the parison molding time in an embodiment of the present invention.

[0027] Figure 2 is a photograph for explaining a method for evaluating the amount of volatile gas generated. It is a photograph showing the volatile gas generated from the thermoplastic resin composition pellet of Comparative Example 1 and the residue remaining on the lid of a petri dish.

[0028] Hereinafter, embodiments of the present invention will be described in detail. However, these are presented as examples and are not intended to limit the present invention, which is defined solely by the appended claims.

[0029] Unless specifically stated herein, 'copolymer' includes random copolymerization, block copolymerization, and graft copolymerization, and 'copolymer' includes random copolymer, block copolymer, and graft copolymer.

[0030] Unless otherwise specified herein, 'weight average molecular weight' is measured by dissolving a powder sample in an appropriate solvent and using Agilent Technologies' 1200 series Gel Permeation Chromatography (GPC) (Shodex polystyrene is used as the standard sample).

[0031] According to one embodiment, (A) 30 to 40 wt% of an acrylonitrile-butadiene-styrene graft copolymer (g-ABS) comprising 50 to 70 wt% of a butadiene-based rubbery polymer having an average particle diameter of 250 to 450 nm; (B) 30 to 50 wt% of a first styrene-acrylonitrile copolymer (SAN) having a weight average molecular weight of 250,000 to 350,000 g / mol and an oligomer content of 0.6 to 1 wt%; (C) 10 to 30 wt% of a second styrene-acrylonitrile copolymer (SAN) having a weight average molecular weight of 100,000 to 150,000 g / mol and an oligomer content of 0.5 wt% or less; (D) 2 to 10 wt% of alpha-methylstyrene-styrene-acrylonitrile copolymer (AMS-SAN); and (E) 1 to 5 wt% of N-phenyl maleimide-styrene-maleic anhydride copolymer (PMI-SM-MAH).

[0032] A thermoplastic resin composition according to one embodiment comprising the above components (A) to (E) may have excellent blow moldability, generate less volatile gas during the production of a molded product, and have an excellent appearance of the molded product. Therefore, each component included in the thermoplastic resin composition will be described in detail below.

[0033] (A) An acrylonitrile-butadiene-styrene graft copolymer containing 50 to 70 wt% of a butadiene-based rubber polymer having an average particle diameter of 250 to 450 nm.

[0034] A thermoplastic resin composition according to one embodiment can have excellent impact resistance, blow moldability, and appearance of a blow molded product by including (A) an acrylonitrile-butadiene-styrene graft copolymer (g-ABS) containing 50 to 70 wt% of a butadiene-based rubber polymer having an average particle diameter of 250 to 450 nm.

[0035] The above (A) acrylonitrile-butadiene-styrene graft copolymer may include a core made of a butadiene-based rubber polymer and a shell formed by graft polymerization of acrylonitrile and styrene onto the core. For example, acrylonitrile and styrene monomers may be added to the core made of the butadiene-based rubber polymer, and graft copolymerization may be performed using a conventional polymerization method such as emulsion polymerization, suspension polymerization, or bulk polymerization to form a shell.

[0036] For example, the above (A) acrylonitrile-butadiene-styrene graft copolymer can form a shell by graft copolymerizing an acrylonitrile monomer and a styrene monomer together into a butadiene-based rubber polymer core.

[0037] The above butadiene-based rubber polymer may be a butadiene rubber polymer, a butadiene-styrene rubber polymer, a butadiene-acrylonitrile rubber polymer, a butadiene-acrylate rubber polymer, or a combination thereof.

[0038] The core made of the above butadiene-based rubber polymer may have an average particle diameter of 250 to 450 nm, for example, 250 to 400 nm, for example, 300 to 450 nm, for example, 300 to 400 nm. By having the average particle diameter of the core within the above range, the thermoplastic resin composition comprising the (A) acrylonitrile-butadiene-styrene graft copolymer may have excellent impact resistance and an excellent blow-molded product appearance.

[0039] The above (A) acrylonitrile-butadiene-styrene graft copolymer may contain the core in an amount of 50 to 70 wt%, for example, 55 to 70 wt%, for example, 60 to 70 wt%, for example, 50 to 65 wt%, for example, 50 to 60 wt%, based on the total weight of the copolymer. By containing the core of the above (A) acrylonitrile-butadiene-styrene graft copolymer in the above range, a thermoplastic resin composition containing the same may have excellent blow moldability.

[0040] The above (A) acrylonitrile-butadiene-styrene graft copolymer may be included in an amount of 30 to 40 wt%, for example, 30 to 38 wt%, for example, 32 to 38 wt%, for example, 33 to 38 wt%, for example, 33 to 37 wt%, based on 100 wt% of the total of the components (A) to (E) of the present invention. By including the (A) acrylonitrile-butadiene-styrene graft copolymer in the above amount, a thermoplastic resin composition including the same can have excellent blow moldability and excellent impact resistance.

[0041] (B) A first styrene-acrylonitrile copolymer having a weight average molecular weight of 250,000 to 350,000 g / mol and an oligomer content of 0.6 to 1 wt%

[0042] A thermoplastic resin composition according to one embodiment includes (B) a first styrene-acrylonitrile copolymer having a weight average molecular weight of 250,000 to 350,000 g / mol and an oligomer content of 0.6 to 1 wt%, thereby improving blow moldability and reducing the amount of volatile gas generated during blow molding.

[0043] The above (B) first styrene-acrylonitrile copolymer may have a weight average molecular weight of 250,000 to 350,000 g / mol, for example, 270,000 to 350,000 g / mol, for example, 300,000 to 350,000 g / mol.

[0044] In addition, the (B) first styrene-acrylonitrile copolymer may have an oligomer content of 0.6 to 1 wt%, for example, 0.7 to 1 wt%, for example, 0.8 to 1 wt%, for example, 0.6 to 0.9 wt%, for example, 0.7 to 0.9 wt%, based on the total weight of the copolymer. By including the oligomer in the (B) first styrene-acrylonitrile copolymer within the above range, the amount of volatile gas generated during blow molding of a thermoplastic resin composition including the same can be reduced, thereby improving the appearance of a blow-molded product.

[0045] The above (B) first styrene-acrylonitrile copolymer may contain structural units derived from styrene in an amount of 60 to 80 wt%, for example, 65 to 80 wt%, for example, 70 to 80 wt%, for example, 60 to 75 wt%, for example, 65 to 70 wt%, based on the total weight of all structural units of the copolymer. Since the above (B) first styrene-acrylonitrile copolymer contains structural units derived from styrene in the above range, a thermoplastic resin composition containing the same may have excellent melt stability and heat resistance.

[0046] The above (B) first styrene-acrylonitrile copolymer may be included in an amount of 30 to 50 wt%, for example, 30 to 45 wt%, for example, 35 to 50 wt%, for example, 35 to 45 wt%, based on 100 wt% of the total of the components (A) to (E) of the present invention. By including the above (B) first styrene-acrylonitrile copolymer in the above amount, a thermoplastic resin composition including the same may have excellent blow moldability and excellent impact resistance.

[0047] (C) A second styrene-acrylonitrile copolymer having a weight average molecular weight of 100,000 to 150,000 g / mol and an oligomer content of 0.5 wt% or less

[0048] A thermoplastic resin composition according to one embodiment includes (C) a second styrene-acrylonitrile copolymer having a weight average molecular weight of 100,000 to 150,000 g / mol and an oligomer content of 0.5 wt% or less, thereby improving the heat resistance of the thermoplastic resin composition including the same and reducing the amount of volatile gas generated during blow molding.

[0049] The above (C) second styrene-acrylonitrile copolymer may have a weight average molecular weight of 100,000 to 150,000 g / mol, for example, 110,000 to 150,000 g / mol, for example, 120,000 to 150,000 g / mol, for example, 100,000 to 140,000 g / mol.

[0050] In addition, the (C) second styrene-acrylonitrile copolymer may have an oligomer content of 0.5 wt% or less, for example, 0.01 to 0.5 wt%, for example, 0.05 to 0.5 wt%, for example, 0.1 to 0.5 wt%, for example, 0.2 to 0.5 wt%, based on the total weight of the copolymer. By limiting the oligomer content in the (C) second styrene-acrylonitrile copolymer to the above range, the heat resistance of a thermoplastic resin composition including the same can be improved, and the amount of volatile gas generated during blow molding can be reduced, thereby improving the appearance of a blow molded product.

[0051] The above (C) second styrene-acrylonitrile copolymer may contain structural units derived from styrene in an amount of 60 to 80 wt%, for example, 65 to 80 wt%, for example, 70 to 80 wt%, for example, 60 to 75 wt%, for example, 65 to 70 wt%, based on the total weight of all structural units of the copolymer. Since the above (C) second styrene-acrylonitrile copolymer contains structural units derived from styrene in the above range, a thermoplastic resin composition containing the same may have excellent melt stability.

[0052] The above (C) second styrene-acrylonitrile copolymer may be included in an amount of 10 to 30 wt%, for example, 10 to 25 wt%, for example, 10 to 20 wt%, for example, 15 to 30 wt%, based on 100 wt% of the total of the components (A) to (E) of the present invention. By including the above (C) second styrene-acrylonitrile copolymer in the above amount, the heat resistance of a thermoplastic resin composition including the same can be improved, and the appearance of a blow-molded product can be excellent.

[0053] (D) alpha-methylstyrene-styrene-acrylonitrile copolymer

[0054] A thermoplastic resin composition according to one embodiment can have improved heat resistance by including (D) an alpha-methylstyrene-styrene-acrylonitrile copolymer.

[0055] The above (D) alpha-methylstyrene-styrene-acrylonitrile copolymer includes a structural unit derived from alpha-methylstyrene, a structural unit derived from styrene, and a structural unit derived from acrylonitrile.

[0056] The above (D) alpha-methylstyrene-styrene-acrylonitrile copolymer may include 50 to 60 wt% of structural units derived from alpha-methylstyrene, 10 to 30 wt% of structural units derived from styrene, and 20 to 30 wt% of structural units derived from acrylonitrile, based on the total weight of all structural units constituting the copolymer. By including the structural units within the above ranges, the heat resistance and discoloration stability of a thermoplastic resin composition including the same may be excellent.

[0057] The weight average molecular weight of the above (D) alpha-methylstyrene-styrene-acrylonitrile copolymer may be 50,000 to 300,000 g / mol, for example, 100,000 to 300,000 g / mol, for example, 100,000 to 200,000 g / mol. When the weight average molecular weight of the above (D) alpha-methylstyrene-styrene-acrylonitrile copolymer satisfies the above range, the heat resistance and blow moldability of a thermoplastic resin composition including the same may be excellent.

[0058] The above (D) alpha-methylstyrene-styrene-acrylonitrile copolymer may be included in an amount of 2 to 10 wt%, for example, 3 to 10 wt%, for example, 2 to 9 wt%, for example, 2 to 7 wt%, based on 100 wt% of the total of the components (A) to (E) of the present invention. By including the (D) alpha-methylstyrene-styrene-acrylonitrile copolymer in the above amount, the heat resistance of a thermoplastic resin composition including it may be improved.

[0059] (E) N-phenyl maleimide-styrene-maleic anhydride copolymer

[0060] A thermoplastic resin composition according to one embodiment can have improved heat resistance by including (E) N-phenyl maleimide-styrene-maleic anhydride copolymer.

[0061] The above (E) N-phenyl maleimide-styrene-maleic anhydride copolymer may include 20 to 60 wt% of structural units derived from N-phenyl maleimide, 20 to 75 wt% of structural units derived from styrene, and 1 to 10 wt% of structural units derived from maleic anhydride, based on the total weight of all structural units constituting the copolymer. By including the structural units within the above ranges, the heat resistance of a thermoplastic resin composition including the same may be further improved.

[0062] The glass transition temperature (Tg) of the above (E) N-phenyl maleimide-styrene-maleic anhydride copolymer may be 150 to 200°C, for example, 155 to 200°C, for example, 165 to 200°C, for example, 175 to 200°C, for example, 185 to 200°C. When the glass transition temperature of the above (E) N-phenyl maleimide-styrene-maleic anhydride copolymer satisfies the above range, the heat resistance of a thermoplastic resin composition including the same may be excellent.

[0063] The weight average molecular weight of the above (E) N-phenyl maleimide-styrene-maleic anhydride copolymer may be 100,000 to 300,000 g / mol, for example, 100,000 to 200,000 g / mol. When the weight average molecular weight of the above (E) N-phenyl maleimide-styrene-maleic anhydride copolymer satisfies the above range, the blow moldability of a thermoplastic resin composition including the same may be excellent.

[0064] The above (E) N-phenyl maleimide-styrene-maleic anhydride copolymer may be included in an amount of 1 to 5 wt%, for example, 2 to 5 wt%, for example, 1 to 4 wt%, for example, 1 to 3 wt%, based on 100 wt% of the total of the (A) to (E) components of the present invention. By including the (E) N-phenyl maleimide-styrene-maleic anhydride copolymer in the above amount, the heat resistance of a thermoplastic resin composition including it can be further improved.

[0065] (F) Additives

[0066] A thermoplastic resin composition according to one embodiment may further include, in addition to the components (A) to (E), one or more additives necessary to balance the properties of the thermoplastic resin composition or depending on the final use of the thermoplastic resin composition.

[0067] Specifically, the additive may be at least one selected from among flame retardants, nucleating agents, coupling agents, glass fibers, plasticizers, lubricants, mineral fillers, antibacterial agents, release agents, heat stabilizers, antioxidants, ultraviolet stabilizers, pigments, dyes, and antistatic agents.

[0068] These additives may be appropriately included within a range that does not impair the physical properties of the thermoplastic resin composition, and may be included in an amount of 0.1 to 20 parts by weight based on a total of 100 parts by weight of the components (A) to (E), but are not limited thereto.

[0069] Another embodiment of the present invention provides a molded article manufactured from the thermoplastic resin composition described above. The molded article can be manufactured by molding the thermoplastic resin composition according to one embodiment using a known method. For example, the molded article can be manufactured in the form of pellets by mixing the components of the thermoplastic resin composition according to one embodiment and other additives, feeding the mixture into an extruder, and then melting / kneading the mixture.

[0070] The above-described molded article can be manufactured from the above-described thermoplastic resin composition using a known molding method or blow molding method. For example, the above-described molded article can be manufactured using methods such as extrusion blow molding and injection blow molding, but is not limited thereto.

[0071] The above-mentioned molded product in the form of pellets may have a melt flow index measured according to ASTM D1238 at 220°C and 10 kg of 3 to 5 g / 10 min, for example, 3.5 to 5 g / 10 min, for example, 3.5 to 4.5 g / 10 min, for example, 3 to 4.5 g / 10 min. Excellent blow moldability may be exhibited within the above melt flow index range.

[0072] By forming a parison through blow molding using a thermoplastic resin composition according to one embodiment, and measuring the length of the formed parison and the hanging time of the parison, the melt strength of the thermoplastic resin composition can be evaluated, and thereby blow moldability can be predicted.

[0073] Specifically, when a pellet-shaped molded article is manufactured from a thermoplastic resin composition according to one embodiment, and the manufactured pellet is put into an extrusion blow molding machine (L / D=40, Φ=40 mm, Single screw) set to a cylinder temperature of 190 to 200°C and a screw rotation speed of 20 to 30 rpm to mold a parison having a diameter of 40 mm and a thickness of 2 mm, when the length of the molded parison reaches 25 cm, the screw rotation speed is adjusted to 0 rpm, and the time taken until the parison separates from the die and begins to fall freely, i.e., the parison hanging time, is measured. As can be seen from the examples described below, the hanging time of the parison molded from the thermoplastic resin composition according to one embodiment exceeds 150 seconds. It can be understood that the longer the parison hanging time, the higher the melt strength of the thermoplastic resin composition manufactured therefrom, and the better the blow moldability of the thermoplastic resin composition. The molding time of a parison manufactured from a thermoplastic resin composition according to one embodiment may be greater than 150 seconds, for example, greater than 160 seconds.

[0074] In one embodiment, the length of the formed parison until it separates from the die and begins to fall freely may be 300 mm or less, for example, 290 mm or less, for example, 280 mm or less, for example, 270 mm or less, for example, 260 mm or less, for example, from 250 to 300 mm, for example, from 250 to 290 mm, for example, from 250 to 280 mm, for example, from 250 to 270 mm, for example, from 250 to 260 mm. When the length of the parison is within the above range, the parison sagging phenomenon due to insufficient melt strength is improved, and thus the blow moldability can be considered to be improved.

[0075] In addition, the molded article manufactured from the thermoplastic resin composition according to one embodiment can measure the amount of volatile gas generated through fogging evaluation. Specifically, the molded article in the form of pellets or cut into pellets having a certain weight, for example, 4 g, is placed in a Petri dish with a glass lid, placed on a hot plate at a certain temperature, for example, 250° C., heated for a certain period of time, for example, 2 hours, and aged to room temperature, and then the weight of the residue remaining on the lid is measured, thereby measuring the amount of volatile gas generated. The molded article manufactured from the thermoplastic resin composition according to one embodiment can have a volatile gas generation amount measured by the above method of 2,100 ppm or less, for example, 2,000 ppm or less, for example, 1,900 ppm or less, for example, 1,800 ppm or less.

[0076] Hereinafter, preferred embodiments of the present invention are described. However, the following examples are merely preferred embodiments of the present invention, and the present invention is not limited to the following examples.

[0077] Example 1 and Comparative Examples 1 to 16

[0078] The thermoplastic resin compositions of Example 1 and Comparative Examples 1 to 16 were prepared according to the component content ratios described in Table 1 below. In Table 1 below, (A) to (E), (x), and (y) are expressed as the weight % of each component based on the total weight of the composition.

[0079] A mixture of the components listed in Table 1 below was dry-mixed and melted / kneaded using a twin-screw extruder (L / D=29, Φ=45 mm) at a barrel temperature of approximately 230°C, and extruded and processed to obtain a thermoplastic resin composition in the form of pellets. Subsequently, the pelletized thermoplastic resin composition was dried at approximately 80°C for approximately 4 hours.

[0080] Classification Implementation Preliminary Comparative Example 112345678910111213141516(A)353535353535353535353535353535353535(B)41-----40-55--57---16-(C)16----40-55----57--41-(D)52525--2525--555555525(E)3--1010--10103333333-(x)-40--55----57---4116-30(y)--4055------57--1641-10

[0081] The description of each composition listed in Table 1 above is as follows. (A) Acrylonitrile-butadiene-styrene graft copolymer (manufacturer: Lotte Chemical) comprising a core (average particle diameter: about 270 nm) made of a butadiene rubber polymer and a shell formed by graft polymerization of acrylonitrile and styrene onto the core, about 60 wt%

[0082] (B) Styrene-acrylonitrile copolymer having a weight average molecular weight of about 320,000 g / mol and an oligomer content of about 0.9 wt% (Manufacturer: Lotte Chemical)

[0083] (C) Styrene-acrylonitrile copolymer having a weight average molecular weight of about 130,000 g / mol and an oligomer content of about 0.4 wt% (Manufacturer: Lotte Chemical)

[0084] (D) Alpha-methylstyrene-styrene-acrylonitrile copolymer containing about 54 wt% of structural units derived from alpha-methylstyrene, about 19 wt% of structural units derived from styrene, and about 27 wt% of structural units derived from acrylonitrile, and having a weight average molecular weight of about 160,000 g / mol (Manufacturer: Lotte Chemical)

[0085] (E) N-phenyl maleimide-styrene-maleic anhydride copolymer (product name: MS-NA, manufacturer: DENKA)

[0086] (x) Styrene-acrylonitrile copolymer having a weight average molecular weight of about 230,000 g / mol and an oligomer content of about 4 wt% (Manufacturer: Lotte Chemical)

[0087] (y) Styrene-acrylonitrile copolymer having a weight average molecular weight of about 130,000 g / mol and an oligomer content of about 3 wt% (Manufacturer: Lotte Chemical)

[0088]

[0089] evaluation

[0090] The following evaluations were performed on pellets manufactured from the thermoplastic resin compositions according to the above examples and comparative examples, and the results are shown in Tables 2 and 3 below.

[0091] (1) Fluidity (unit: g / 10min)

[0092] The melt flow index (MFI) of the pellets according to the above examples and comparative examples was measured according to ASTM D1238 at 220℃ and 10 kg. A higher MFI value indicates better fluidity.

[0093] (2) Blow moldability

[0094] (2-1) Parison forming time (unit: seconds)

[0095] The pellets according to the above examples and comparative examples were fed into an extrusion blow molding machine equipped with a die attached to a single screw extruder (L / D=40, Φ=40 mm) capable of forming a parison with a diameter of 40 mm and a thickness of 2 mm in the form of a hollow pipe, and the parison was formed under the conditions of a cylinder temperature of 200°C and a screw rotation speed of 30 rpm. When the length of the formed parison reached 25 cm, the screw rotation speed was adjusted to 0 rpm, and the time required until the parison was separated from the die and began to fall freely, i.e., the parison forming time (hanging time), was measured. The longer the parison forming time, the higher the melt strength and the better the blow moldability.

[0096] (2-2) Parison length (unit: mm)

[0097] When measuring the above parison forming time, the length of the freely falling parison was measured. The freely falling parison is as shown in Fig. 1, and the shorter the length of the freely falling parison, the less the parison sagging phenomenon during blow molding and the better the blow moldability.

[0098] (3) Volatile gas generation amount (unit: ppm)

[0099] The amount of volatile gas generation was measured through fogging evaluation. Specifically, 4.0 g of pellets according to the examples and comparative examples were placed in a petri dish with a glass lid, placed on a hot plate at 250°C, heated for 2 hours, and then aged to room temperature. The weight of the lid before and after heating was measured to obtain the amount of residue remaining on the lid, and the amount of volatile gas generation was calculated from this. Fig. 2 is a photograph showing the appearance of residue remaining on the petri dish lid due to volatile gas generation from the thermoplastic resin composition pellet of Comparative Example 1. The lower the amount of volatile gas generation, the better the appearance of the blow-molded product.

[0100] Example Comparative Example 112345678 Melt Flow Index (g / 10min) 3.6 3.8 6.26.0 3.5 6.0 3.5 5.0 3.0 Parison Forming Time (sec) 185 120 655 510 575 185 60 145 Parison Length (mm) 280 295 350 340 290 340 280 325 285 Volatile Gas Emission (ppm) 2,000 5,85 06,200 5,000 4,85 03,200 2,800 2,000 1,800

[0101] Comparative Example 910111213141516 Melt Flow Index (g / 10min) 3.86.22.86.54.25.55.04.5 Parison Forming Time (sec) 150702006512515511590 Parison Length (mm) 300340270325290310300310 Volatile Gas Emission (ppm) 5,8506,2005,0004,8503,2002,8002,0006,000

[0102] Referring to Tables 2 and 3 above, it can be confirmed that the thermoplastic resin composition according to the comparative example in which any one of the components (A) to (E) is excluded has inferior fluidity, blow moldability, and / or volatile gas generation compared to the thermoplastic resin composition according to the example. As shown in Fig. 1, the left side is a parison molded from the thermoplastic resin composition according to Example 1, and the right side is a parison molded from the thermoplastic resin composition according to Comparative Example 14. In the case of Comparative Example 14, the length of the parison is longer than that of Example 1, confirming inferior blow moldability.

[0103] Therefore, it can be confirmed that the thermoplastic resin composition according to the embodiment including the components (A) to (E) within the content range of the patent claims of the present invention has excellent blow moldability and has excellent appearance characteristics of the molded product due to a small amount of volatile gas generated during blow molding.

[0104] Although the present invention has been described above through preferred embodiments as described above, the present invention is not limited thereto, and those engaged in the technical field to which the present invention pertains will readily understand that various modifications and variations are possible without departing from the concept and scope of the patent claims described below.

Claims

1. (A) 30 to 40 wt% of an acrylonitrile-butadiene-styrene graft copolymer comprising 50 to 70 wt% of a butadiene-based rubber polymer having an average particle diameter of 250 to 450 nm; (B) 30 to 50 wt% of a first styrene-acrylonitrile copolymer having a weight average molecular weight of 250,000 to 350,000 g / mol and an oligomer content of 0.6 to 1 wt%; (C) 10 to 30 wt% of a second styrene-acrylonitrile copolymer having a weight average molecular weight of 100,000 to 150,000 g / mol and an oligomer content of 0.5 wt% or less; (D) 2 to 10 wt% of alpha-methylstyrene-styrene-acrylonitrile copolymer; and (E) A thermoplastic resin composition comprising 1 to 5 wt% of an N-phenyl maleimide-styrene-maleic anhydride copolymer.

2. In paragraph 1, the (A) acrylonitrile-butadiene-styrene graft copolymer is a thermoplastic resin composition having a core-shell structure including a core made of a butadiene-based rubber polymer and a shell formed by graft polymerizing acrylonitrile and styrene onto the core.

3. In paragraph 1 or paragraph 2, the (B) first styrene-acrylonitrile copolymer is a thermoplastic resin composition comprising 60 to 80 wt% of structural units derived from styrene and 20 to 40 wt% of structural units derived from acrylonitrile, based on the total weight of all structural units of the copolymer.

4. A thermoplastic resin composition according to any one of claims 1 to 3, wherein the (C) second styrene-acrylonitrile copolymer comprises 60 to 80 wt% of structural units derived from styrene and 20 to 40 wt% of structural units derived from acrylonitrile, based on the total weight of all structural units of the copolymer.

5. A thermoplastic resin composition according to any one of claims 1 to 4, wherein the (D) alpha-methylstyrene-styrene-acrylonitrile copolymer comprises 50 to 60 wt% of structural units derived from alpha-methylstyrene, 10 to 30 wt% of structural units derived from styrene, and 20 to 30 wt% of structural units derived from acrylonitrile, based on the total weight of all structural units of the copolymer.

6. A thermoplastic resin composition according to any one of claims 1 to 5, wherein the (E) N-phenyl maleimide-styrene-maleic anhydride copolymer comprises 20 to 60 wt% of structural units derived from N-phenyl maleimide, 20 to 75 wt% of structural units derived from styrene, and 1 to 10 wt% of structural units derived from maleic anhydride, based on the total weight of all structural units of the copolymer.

7. A thermoplastic resin composition according to any one of claims 1 to 6, wherein the glass transition temperature of the (E) N-phenyl maleimide-styrene-maleic anhydride copolymer is 150 to 200°C.

8. A thermoplastic resin composition according to any one of claims 1 to 7, wherein the weight average molecular weight of the (D) alpha-methylstyrene-styrene-acrylonitrile copolymer is 50,000 to 300,000 g / mol.

9. A thermoplastic resin composition according to any one of claims 1 to 8, wherein the weight average molecular weight of the (E) N-phenyl maleimide-styrene-maleic anhydride copolymer is 100,000 to 300,000 g / mol.

10. A thermoplastic resin composition according to any one of claims 1 to 9, wherein the thermoplastic resin composition further comprises at least one additive selected from among a flame retardant, a nucleating agent, a coupling agent, glass fiber, a plasticizer, a lubricant, a mineral filler, an antibacterial agent, a release agent, a heat stabilizer, an antioxidant, an ultraviolet stabilizer, a pigment, a dye, and an antistatic agent.

11. A molded product manufactured from the thermoplastic resin composition of any one of claims 1 to 10.

12. In paragraph 11, the molded product in the form of a pellet has a melt flow index of 3 to 5 g / 10 min measured according to ASTM D1238 under conditions of 220°C and 10 kg.

13. In paragraph 11 or 12, when the pellet-shaped molded product is fed into an extrusion blow molding machine set to a barrel temperature of 190 to 200°C and a screw rotation speed of 20 to 30 rpm to mold a parison having a diameter of 40 mm and a thickness of 2 mm, a molded product in which the time taken until the parison separates from the die and begins to fall freely after the screw rotation speed is adjusted to 0 rpm when the length of the molded parison reaches 25 cm is more than 150 seconds.

14. A molded product in paragraph 13, wherein the length of the molded parison until it separates from the die and begins to fall freely is 300 mm or less.

15. A molded product in which, when 4 g of the molded product in the form of a pellet is placed in a petri dish with a glass lid, placed on a hot plate at 250°C, heated for 2 hours, and aged to room temperature, the amount of volatile gas generated is 2,100 ppm or less, as measured from the residue remaining on the lid, in any one of clauses 11 to 14.

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