Flame-retardant polypropylene resin composition excellent in moisture heat stability and compact produced therefrom

Abstract

To provide a polypropylene resin composition excellent in both processability and stability of humid heat stability and a compact produced therefrom.SOLUTION: Based on the total weight of components (A) to (C), the flame-retardant polypropylene resin composition comprises: (A) 30-55 wt% of polypropylene resins selected from homopolymer polypropylene, polypropylene copolymers, and polypropylene terpolymers; (B) 18-30 wt% of a flame retardant composed of piperazine pyrophosphate and melamine polyphosphate; (C) 17-40 wt% of a reinforcing agent. The polypropylene resin (A) includes a first polypropylene resin (A1) and a second polypropylene resin (A2) with different melt flow indices. When measured at a temperature of 230°C under a 2.16 kg load according to ASTM D1238, the melt flow index of the second polypropylene resin (A2) is characterized to be 1350-1450 g / 10 min.SELECTED DRAWING: Figure 1

Description

Technical Field

[0001] The present invention relates to a flame-retardant polypropylene resin composition having excellent heat and humidity resistance stability and a molded article produced therefrom. Specifically, the present invention relates to a polypropylene resin composition having excellent flame retardancy and excellent elution resistance of a flame retardant, and a molded article produced therefrom.

Background Art

[0002] Polypropylene resin, which is a kind of general-purpose resin, is excellent not only in economy but also in mechanical properties, moldability, chemical resistance, etc., and is variously used as materials for films, pipes, interior and exterior parts of automobiles, parts of electric and household appliances, building and industrial materials, etc.

[0003] Since such a polypropylene resin is basically a flammable substance, attempts have been made to impart flame retardancy to the polypropylene resin.

[0004] For example, Patent Document 1 discloses a polyolefin resin composition using a phosphorus-nitrogen-based flame retardant, but does not disclose a flame-retardant polypropylene resin composition having excellent heat and humidity resistance stability.

[0005] Further, Patent Document 2 discloses a polyolefin resin composition containing a halogen-based flame retardant, antimony trioxide, and a high molecular weight ester compound, but has a limitation that toxic gas can be generated from the halogen-based flame retardant.

[0006] Therefore, there is a demand for the development of a polypropylene resin composition excellent in both flame retardancy and heat and humidity stability.

Prior Art Documents

Patent Documents

[0007]

Patent Document 1

Patent Document 2

Summary of the Invention

Problems to be Solved by the Invention

[0008] An object of the present invention is to provide a polypropylene resin composition excellent in both processability and stability to wet heat, and a molded article produced therefrom.

Means for Solving the Problems

[0009] According to one embodiment of the present invention for achieving the above object, based on the total weight of components (A) to (C), (A) 30 to 55% by weight of a polypropylene-based resin selected from a propylene homopolymer, a propylene copolymer, and a propylene terpolymer; (B) 18 to 30% by weight of a flame retardant in which piperazine pyrophosphate and melamine polyphosphate are combined; (C) 17 to 40% by weight of a reinforcing agent, wherein the polypropylene-based resin (A) includes a first polypropylene-based resin (A1) and a second polypropylene-based resin (A2) having different melt indices from each other, and when measured at 230°C with a 2.16 kg load in accordance with ASTM D1238, the melt index of the second polypropylene-based resin (A2) is 1350 to 1450 g / 10 minutes, and a flame-retardant polypropylene resin composition is provided.

[0010] In a specific example of the present invention, the polypropylene-based resin (A) may be a propylene homopolymer.

[0011] In a specific example of the present invention, the content of the second polypropylene-based resin (A2) in the flame-retardant polypropylene resin composition may be 5 to 20% by weight.

[0012] In a specific example of the present invention, the phosphorus content in the flame retardant (B) may be 18 to 22% by weight, and the nitrogen content may be 17 to 22% by weight.

[0013] In a specific example of the present invention, the content of melamine polyphosphate in the flame retardant (B) can be 20 to 40% by weight.

[0014] In a specific example of the present invention, the reinforcing agent (C) may include at least one selected from the group consisting of glass fiber, glass beads, and glass flakes.

[0015] In a specific example of the present invention, the flame-retardant polypropylene resin composition may further contain 0 to 5 parts by weight of a compatibilizer (D); 0 to 1.0 part by weight of an antioxidant (E); 0 to 1.0 part by weight of a halogen absorber (F); 0 to 1.0 part by weight of a drip inhibitor (G); and 0 to 2 parts by weight of a pigment (H) based on 100 parts by weight of components (A) to (C).

[0016] In a specific example of the present invention, the compatibilizer (D) may be one in which maleic anhydride is grafted onto a polypropylene-based resin.

[0017] In a specific example of the present invention, the antioxidant (E) may include at least one selected from the group consisting of pentaerythritol tetrakis[3-(3,5-di-t-butyl-4-hydroxyphenyl)propionate], 1,3,5-trimethyl-2,4,6-tris(3,5-di-t-butyl-4-hydroxybenzyl)benzene, 2',3-bis[{3-(3,5-di-t-butyl-4-hydroxyphenyl)propionyl}]propionohydrazide, and tris(2,4-di-t-butylphenyl)phosphite.

[0018] In a specific example of the present invention, the halogen absorber (F) is calcium stearate and hydrotalcite (Mg 1-x Al x (OH)2(CO3) x / 2 ·mH2O) and may include at least one selected from the group consisting of.

[0019] In a specific example of the present invention, the drip inhibitor (G) includes at least one fluorine-based drip inhibitor selected from the group consisting of polytetrafluoroethylene, polyvinylidene fluoride, polyhexafluoropropylene, sodium perfluoromethanesulfonate, potassium perfluoron-butanesulfonate, potassium perfluorot-butanesulfonate, sodium perfluorooctanesulfonate, and calcium perfluoro-2-ethylhexanesulfonate, and the drip inhibitor can be in the form of a masterbatch dispersed in a polypropylene-based resin.

[0020] In a specific example of the present invention, the pigment (H) includes at least one inorganic pigment selected from the group consisting of carbon black, aluminum flakes, aluminum powder, aluminum foil, zinc powder, bronze powder, nacreous mica, titanium white, zinc oxide, zinc sulfide, chrome yellow, barium yellow, ultramarine, cobalt blue, and cobalt green, at least one organic pigment selected from the group consisting of Watchung Red, Permanent Red, Palladium Red, Benzidine Yellow, and Phthalocyanine Green, or a mixture thereof, and the pigment can be in the form of a masterbatch dispersed in a low-density polyethylene-based resin.

[0021] In a specific example of the present invention, the flame-retardant polypropylene resin composition may further include at least one additive selected from the group consisting of a neutralizing agent, a slip agent, an antiblocking agent, a filler, a weather stabilizer, an antistatic agent, an activator, a nucleating agent, and a dye.

[0022] According to another embodiment of the present invention, there is provided a flame-retardant polypropylene resin molded article manufactured by molding the flame-retardant polypropylene resin composition.

[0023] In a specific example of the present invention, when the flame-retardant polypropylene resin molded article is measured by the UL94 vertical test method based on a thickness of 1.5 mm, it can satisfy the V0 standard.

[0024] In a specific example of the present invention, when the flame-retardant polypropylene resin molded article is subjected to the elution resistance test of the flame retardant at a temperature of 85°C and a relative humidity of 85%, it can satisfy the condition of 1000 hours or more.

[0025] In a specific example of the present invention, the flame-retardant polypropylene resin molded article can be a home appliance or an automobile part.

Effect of the Invention

[0026] The polypropylene resin composition according to the implementation example of the present invention is excellent in both moisture and heat resistance stability and flame retardancy, and thus can be effectively used in applications where weather resistance, light resistance, and mold release properties are required.

Brief Description of the Drawings

[0027]

Figure 1

Modes for Carrying Out the Invention

[0028] Hereinafter, the present invention will be described in more detail. The flame-retardant polypropylene resin composition according to an implementation example of the present invention contains, based on the total weight of components (A) to (C), 30 to 55% by weight of a polypropylene resin selected from a propylene homopolymer, a propylene copolymer, and a propylene terpolymer; 18 to 30% by weight of a flame retardant in which piperazine pyrophosphate and melamine polyphosphate are combined; and 17 to 40% by weight of a reinforcing agent.

[0029] (A) Polypropylene resin The flame-retardant polypropylene resin composition according to an implementation example of the present invention contains a polypropylene-based resin (A). Specifically, the polypropylene-based resin (A) can be selected from a propylene homopolymer, a propylene copolymer, and a propylene terpolymer.

[0030] The propylene homopolymer can be a polymer obtained by polymerizing propylene monomers substantially alone.

[0031] There is no particular limitation on the method for producing the propylene homopolymer, and the method for producing the propylene homopolymer known in the technical field to which the present invention belongs can be used as it is or with appropriate modifications. For example, a bulk polymerization method, a solution polymerization method, a slurry polymerization method, a gas-phase polymerization method, etc. can be used, and either a batch type or a continuous type is possible.

[0032] In a specific example of the present invention, the polypropylene-based resin (A) can be a propylene homopolymer.

[0033] The propylene copolymer can be a propylene-α-olefin random copolymer or an ethylene-propylene block copolymer, but is not particularly limited thereto.

[0034] The propylene-α-olefin random copolymer can be a random copolymer of propylene and ethylene, or propylene and an α-olefin having 4 to 8 carbon atoms.

[0035] There is no particular limitation on the method for producing the propylene-α-olefin random copolymer, and the method for producing the propylene-α-olefin random copolymer known in the technical field to which the present invention belongs can be used as it is or with appropriate modifications. For example, a bulk polymerization method, a solution polymerization method, a slurry polymerization method, a gas-phase polymerization method, etc. can be used, and either a batch type or a continuous type is possible.

[0036] The ethylene-propylene block copolymer can be obtained by the stepwise polymerization in a reactor of a matrix component of a propylene homopolymer or a propylene-α-olefin random copolymer and an ethylene-propylene rubber copolymer component.

[0037] There is no particular limitation on the method for producing the ethylene-propylene block copolymer, and the method for producing the ethylene-propylene block copolymer known in the technical field to which the present invention pertains can be used as it is or with appropriate modifications. For example, in a commercialized process such as the Spherizone process of LyondellBasell, the Hypol process of Mitsui, or the Unipol process of Grace, the ethylene-propylene block copolymer can be produced by a polymerization method known to ordinary technicians.

[0038] The propylene-based terpolymer can be a terpolymer of propylene, ethylene, and an α-olefin having 4 to 8 carbon atoms. The propylene-based terpolymer can be produced using the production process used in the method for producing the propylene-based copolymer.

[0039] In a specific example of the present invention, the polypropylene-based resin (A) can include a first polypropylene-based resin (A1) and a second polypropylene-based resin (A2) having different melt indices. At this time, the melt index (MI) of the second polypropylene-based resin (A2) can be 1350 to 1450 g / 10 minutes when measured at 230°C with a 2.16 kg load in accordance with ASTM D1238.

[0040] The flame-retardant polypropylene resin composition according to one embodiment of the present invention contains the polypropylene-based resin (A) in a content of 30 to 55% by weight based on the total weight of the components (A) to (C). If the content of the polypropylene-based resin (A) is less than 30% by weight, the mechanical properties of the molded product may deteriorate, and if the content exceeds 55% by weight, it is difficult to obtain sufficient flame retardancy.

[0041] In a specific example of the present invention, the content of the second polypropylene-based resin (A2) in the flame-retardant polypropylene resin composition can be 5 to 20% by weight. When the content of the second polypropylene-based resin (A2) satisfies this range, the flame-retardant polypropylene resin composition can exhibit excellent processability.

[0042] (B) Flame retardant The flame-retardant polypropylene resin composition according to an implementation example of the present invention contains a flame retardant (B). The flame retardant (B) is a non-halogen-based flame retardant, which is a flame retardant in which piperazine pyrophosphate and melamine polyphosphate are combined.

[0043] In a specific example of the present invention, the phosphorus content in the flame retardant (B) can be 18 to 22% by weight, and the nitrogen content can be 17 to 22% by weight. By satisfying the above ranges of the phosphorus and nitrogen contents in the flame retardant respectively, it is excellent in terms of char formation and flame retardancy, and the blooming phenomenon of the flame retardant does not occur in a high-temperature and high-humidity environment.

[0044] Also, in a specific example of the present invention, the content of melamine polyphosphate in the flame retardant (B) can be 20 to 40% by weight. When the content of melamine polyphosphate in the flame retardant (B) exceeds the above range, although the flame retardancy increases, the heat resistance decreases during product processing, and gas generation and the blooming phenomenon of the flame retardant may occur. When the content of melamine polyphosphate is less than the above range, the heat resistance increases, but the flame retardancy may decrease.

[0045] The flame-retardant polypropylene resin composition according to an implementation example of the present invention contains the flame retardant (B) in a content of 18 to 30% by weight based on the total weight of components (A) to (C). When the content of the flame retardant (B) is less than 18% by weight, the flame retardancy of the resin composition may be insufficient. On the other hand, when the content of the flame retardant (B) exceeds 30% by weight, the mechanical properties or processability of the resin composition may decrease.

[0046] (C) Reinforcing agent The flame-retardant polypropylene resin composition according to an implementation example of the present invention contains a reinforcing agent (C).

[0047] In a specific example of the present invention, the reinforcing agent (C) may include at least one selected from the group consisting of glass fiber, glass beads, and glass flakes. As long as the reinforcing agent is generally used in polypropylene resin compositions, its form, size, etc. are not particularly limited.

[0048] The flame-retardant polypropylene resin composition according to an implementation example of the present invention contains the reinforcing agent (C) in a content of 17 to 40% by weight based on the total weight of components (A) to (C). When the content of the reinforcing agent (C) satisfies the above range, the flame-retardant polypropylene resin composition can exhibit excellent mechanical properties and processability.

[0049] In a specific example of the present invention, the flame-retardant polypropylene resin composition according to an implementation example of the present invention may further contain 0 to 5 parts by weight of (D) compatibilizer; 0 to 1.0 part by weight of (E) antioxidant; 0 to 1.0 part by weight of (F) halogen absorber; 0 to 1.0 part by weight of (G) anti-dripping agent; and 0 to 2 parts by weight of (H) pigment, based on 100 parts by weight of components (A) to (C).

[0050] (D) Compatibilizer The flame-retardant polypropylene resin composition according to an implementation example of the present invention may contain a compatibilizer (D).

[0051] In a specific example of the present invention, the compatibilizer (D) may be one in which maleic anhydride is grafted onto a polypropylene-based resin. As long as the compatibilizer is generally used in polypropylene resin compositions, its composition, physical properties, etc. are not particularly limited.

[0052] The flame-retardant polypropylene resin composition according to an implementation example of the present invention may contain the compatibilizer (D) in a content of 0 to 5 parts by weight based on 100 parts by weight of components (A) to (C). When the compatibilizer (D) is included within the above content range, the compatibility of the polypropylene-based resin (A), the flame retardant (B), and the reinforcing agent (C) can be improved.

[0053] (E) Antioxidant The flame - retardant polypropylene resin composition according to an implementation example of the present invention may contain an antioxidant (E).

[0054] In a specific example of the present invention, the antioxidant (E) may contain at least one selected from the group consisting of pentaerythritol tetrakis [3 - (3,5 - di - t - butyl - 4 - hydroxyphenyl) propionate], 1,3,5 - trimethyl - 2,4,6 - tris(3,5 - di - t - butyl - 4 - hydroxybenzyl) benzene, 2’,3 - bis[{3 - (3,5 - di - t - butyl - 4 - hydroxyphenyl) propionyl}] propionohydrazide, and tris(2,4 - di - t - butylphenyl) phosphite.

[0055] The flame - retardant polypropylene resin composition according to an implementation example of the present invention may contain the antioxidant (E) in a content of 0 to 1.0 parts by weight with respect to 100 parts by weight of components (A) to (C). When the antioxidant (E) is contained within the above content range, the long - term heat resistance of the resin composition can be improved.

[0056] (F) Halogen absorbent The flame - retardant polypropylene resin composition according to an implementation example of the present invention may contain a halogen absorbent (F).

[0057] In a specific example of the present invention, the halogen absorbent (F) may contain at least one selected from the group consisting of calcium stearate and hydrotalcite (Mg 1-x Al x (OH)2(CO3) x / 2 ·mH2O).

[0058] The flame - retardant polypropylene resin composition according to an implementation example of the present invention may contain the halogen absorbent (F) in a content of 0 to 1.0 parts by weight with respect to 100 parts by weight of components (A) to (C). When the halogen absorbent (F) is contained within the above content range, the residual components of the catalyst used in the production of the polypropylene - based resin (A) can be effectively removed.

[0059] (G) Dripping inhibitor The flame - retardant polypropylene resin composition according to an embodiment of the present invention may contain a dripping inhibitor (G). The dripping inhibitor (G) plays a role of preventing dripping from occurring when the resin composition is burned.

[0060] In a specific example of the present invention, the dripping inhibitor (G) may contain at least one fluorine - based dripping inhibitor selected from the group consisting of polytetrafluoroethylene, polyvinylidene fluoride, polyhexafluoropropylene, sodium perfluoromethanesulfonate, potassium perfluoron - butanesulfonate, potassium perfluoro - t - butanesulfonate, sodium perfluorooctanesulfonate, and calcium perfluoro - 2 - ethylhexanesulfonate.

[0061] Preferably, the dripping inhibitor (G) can be in the form of a masterbatch dispersed in a polypropylene - based resin.

[0062] The flame - retardant polypropylene resin composition according to an embodiment of the present invention may contain the dripping inhibitor (G) in a content of 0 to 1.0 parts by weight based on 100 parts by weight of components (A) to (C). When the dripping inhibitor (G) is contained within the above - mentioned content range, an appropriate dripping prevention effect can be expected.

[0063] (H) Pigment The flame - retardant polypropylene resin composition according to an embodiment of the present invention may contain a pigment (H).

[0064] In a specific example of the present invention, the pigment (H) may include at least one inorganic pigment selected from the group consisting of carbon black, aluminum flakes, aluminum powder, aluminum foil, zinc powder, bronze powder, pearl mica, titanium white, zinc oxide, zinc sulfide, chrome yellow, barium yellow, ultramarine, cobalt blue, and cobalt green, at least one organic pigment selected from the group consisting of watching red, permanent red, palladium red, benzidine yellow, and phthalocyanine green, or a mixture thereof.

[0065] Preferably, the pigment (H) can be in the form of a masterbatch dispersed in a low-density polyethylene-based resin.

[0066] The flame-retardant polypropylene resin composition according to one embodiment of the present invention may contain the pigment (H) in an amount of 0 to 2 parts by weight based on 100 parts by weight of the components (A) to (C). When the pigment (H) is contained within the above content range, a desired coloring effect can be obtained without inhibiting other physical properties of the resin composition.

[0067] (I) Additives The flame-retardant polypropylene resin composition according to an embodiment of the present invention may further contain ordinary additives without departing from the scope of the present invention. For example, the flame-retardant polypropylene resin composition according to an embodiment of the present invention may further contain at least one additive selected from the group consisting of a neutralizing agent, a slip agent, an antiblocking agent, a filler, a weather stabilizer, an antistatic agent, an activator, a nucleating agent, and a dye.

[0068] There is no particular limitation on the method for producing the flame-retardant polypropylene resin composition according to an embodiment of the present invention. The method for producing a polypropylene resin composition known in the technical field to which the present invention belongs can be used as it is or appropriately modified, and each of the above resin components and compounds can be freely selected and mixed according to a desired procedure without being restricted by a special procedure.

[0069] Specifically, for example, an appropriate amount of each of the aforementioned resins and compounds is mixed in a kneader such as a Hensel mixer, kneader, roll, Banbury mixer for 1 to 2 hours, and then melted and kneaded at a temperature of 160 to 230 °C using a single-screw / twin-screw extruder to produce a pelletized polypropylene resin composition.

[0070] According to another embodiment of the present invention, there is provided a flame-retardant polypropylene resin molded article produced by molding the flame-retardant polypropylene resin composition of the present invention.

[0071] There are no particular restrictions on the method for producing a molded article from the flame-retardant polypropylene resin composition according to the embodiments of the present invention, and methods known in the technical field to which the present invention pertains can be used. For example, a polypropylene resin molded article can be produced by molding the flame-retardant polypropylene resin composition according to the embodiments of the present invention by ordinary methods such as injection molding, extrusion molding, and casting molding.

[0072] In a specific example of the present invention, when the flame-retardant polypropylene resin molded article is measured by the UL94 vertical test method based on a thickness of 1.5 mm, it can satisfy the V0 standard.

[0073] In a specific example of the present invention, when the flame-retardant polypropylene resin molded article is subjected to a test for the elution resistance of the flame retardant at a temperature of 85 °C and a relative humidity of 85%, it can satisfy the condition of 1000 hours or more.

[0074] In a specific example of the present invention, the flame-retardant polypropylene resin molded article can be a home appliance or an automotive part.

[0075] (Examples) Hereinafter, the present invention will be described in more detail with reference to examples and comparative examples. However, the following examples are merely for illustrative purposes of the present invention, and the scope of the present invention is not limited thereto.

[0076] The raw materials used in the examples and comparative examples are as follows. A1: Propylene homopolymer resin (Hanwha Total Energy / HJ700; MI 30 g / 10 min) A2: Propylene homopolymer resin (Hanwha Total Energy / HR1004; MI 1400 g / 10 min) B1: Flame retardant (Phosphorus / nitrogen-based flame retardant in which piperazine phosphate and melamine polyphosphate are blended at a weight ratio of 7:3) B2: Flame retardant (Phosphorus / nitrogen-based flame retardant in which diphosphonic acid, piperazine and melamine polyphosphate are blended at a weight ratio of 27.5:27.5:45) B3: Flame retardant (Phosphorus-based flame retardant; Exolite AP422) B4: Flame retardant (Phosphorus-based flame retardant; Exolite AP462) C1: Reinforcing agent (Glass fiber) D1: Compatibilizer (Resin in which maleic anhydride is grafted onto polypropylene at 1 wt%) E1: Antioxidant (Pentaerythritol tetrakis{3-(3,5-di-t-butyl-4-hydroxyphenyl)propionate}) E2: Antioxidant (Tris(2,4-di-t-butylphenyl)phosphite) E3: Antioxidant (2’,3-Bis[{3-(3,5-di-t-butyl-4-hydroxyphenyl)propionyl}]propionohydrazide) F1: Halogen absorber (Calcium stearate) G1: Drip inhibitor (TEFLON (registered trademark) MPP-5050; 5:5 weight ratio masterbatch of polypropylene and polytetrafluoroethylene (PTFE)) H1: Pigment (55:45 weight ratio masterbatch of low density polyethylene and carbon black)

[0077] (Production Example) The resins and compounds of the types and contents as shown in Table 1 below were melt-blended at a temperature of about 180 to 210 °C using a twin-screw extruder and pelletized. The content of each of components A to C indicates the weight % based on the total weight thereof, and the content of each of components D to H indicates the parts by weight based on 100 parts by weight of components A to C100.

[0078]

Table 1

[0079] (Test Example) The polypropylene resin compositions obtained in each of the examples and comparative examples and the test pieces produced therefrom were tested by the following method. The results are shown in Table 2 and FIG. 1 below.

[0080] (1) Flame retardancy The flame retardancy of injection test pieces with a thickness of 1.5 mm was measured by the UL94 vertical test method.

[0081] (2) Evaluation of flame retardant elution resistance After maintaining ISO standard test pieces at a temperature of 85° C. and a relative humidity of 85% for 1000 hours, it was visually confirmed whether or not the flame retardant had migrated to the surface of the test pieces.

[0082]

Table 2

[0083] As confirmed from Table 1 and Table 2 above, the polypropylene resin compositions of the examples belonging to the scope of the present invention were excellent in both flame retardancy and flame retardant elution resistance.

[0084] On the other hand, in the case of resin compositions containing flame retardants not belonging to the scope of the present invention, none of them had good flame retardant elution resistance.

[0085] Therefore, since the flame-retardant polypropylene resin composition according to the examples belonging to the scope of the present invention is excellent in both flame retardant elution resistance and flame retardancy, it can be effectively used for home appliances, automotive parts, and the like.

Claims

1. 1. A flame-retardant polypropylene resin composition comprising, based on the total weight of components (A) to (C), 30 to 55% by weight of (A) a polypropylene-based resin selected from a propylene homopolymer, a propylene-based copolymer, and a propylene-based terpolymer; 18 to 30% by weight of (B) a flame retardant comprising a combination of piperazine pyrophosphate and melamine polyphosphate; and 17 to 40% by weight of (C) a reinforcing agent, wherein the polypropylene-based resin (A) comprises a first polypropylene-based resin (A1) and a second polypropylene-based resin (A2) having different melt indices, and the second polypropylene-based resin (A2) has a melt index of 1,350 to 1,450 g / 10 min when measured at 230° C. under a load of 2.16 kg in accordance with ASTM D1238.

2. The flame-retardant polypropylene resin composition according to claim 1, wherein the polypropylene-based resin (A) is a propylene homopolymer.

3. The flame-retardant polypropylene resin composition according to claim 1, wherein the content of the second polypropylene resin (A2) in the flame-retardant polypropylene resin composition is 5 to 20% by weight.

4. The flame-retardant polypropylene resin composition according to claim 1, wherein the phosphorus content in the flame retardant (B) is 18 to 22% by weight and the nitrogen content is 17 to 22% by weight.

5. The flame-retardant polypropylene resin composition according to claim 1, wherein the content of melamine polyphosphate in the flame retardant (B) is 20 to 40% by weight.

6. The flame-retardant polypropylene resin composition according to claim 1, wherein the reinforcing agent (C) comprises at least one selected from the group consisting of glass fibers, glass beads, and glass flakes.

7. The flame-retardant polypropylene resin composition according to claim 1, further comprising, relative to 100 parts by weight of the components (A) to (C), 0 to 5 parts by weight of (D) a compatibilizer; 0 to 1.0 part by weight of (E) an antioxidant; 0 to 1.0 part by weight of (F) a halogen absorber; 0 to 1.0 part by weight of (G) an anti-drip agent; and 0 to 2 parts by weight of (H) a pigment.

8. The flame-retardant polypropylene resin composition according to claim 7, wherein the compatibilizer (D) is a polypropylene resin grafted with maleic anhydride.

9. The flame-retardant polypropylene resin composition according to claim 7, wherein the antioxidant (E) comprises at least one selected from the group consisting of pentaerythritol tetrakis[3-(3,5-di-t-butyl-4-hydroxyphenyl)propionic acid], 1,3,5-trimethyl-2,4,6-tris(3,5-di-t-butyl-4-hydroxybenzyl)benzene, 2',3-bis[{3-(3,5-di-t-butyl-4-hydroxyphenyl)propionyl}]propionohydrazide, and tris(2,4-di-t-butylphenyl)phosphite.

10. The halogen absorber (F) is calcium stearate and hydrotalcite (hydrotalcite, Mg １－ｘ A ｘ (OH) ２ (CO ３ ) ｘ／２ ・mH ２ The flame-retardant polypropylene resin composition according to claim 7, further comprising at least one selected from the group consisting of:

11. The flame-retardant polypropylene resin composition according to claim 7, wherein the anti-drip agent (G) comprises at least one fluorine-based anti-drip agent selected from the group consisting of polytetrafluoroethylene, polyvinylidene fluoride, polyhexafluoropropylene, sodium perfluoromethanesulfonate, potassium perfluoro-n-butanesulfonate, potassium perfluoro-t-butanesulfonate, sodium perfluorooctanesulfonate, and calcium perfluoro-2-ethylhexanesulfonate, and the anti-drip agent is in the form of a master batch dispersed in the polypropylene resin.

12. The flame-retardant polypropylene resin composition according to claim 7, wherein the pigment (H) is at least one inorganic pigment selected from the group consisting of carbon black, aluminum flake, aluminum powder, aluminum foil, zinc powder, bronze powder, pearl mica, titanium white, zinc oxide, zinc sulfide, chrome yellow, barium yellow, ultramarine, cobalt blue, and cobalt green, at least one organic pigment selected from the group consisting of Watchung Red, Permanent Red, Palladium Red, Benzidine Yellow, and Phthalocyanine Green, or a mixture thereof, and the pigment is in the form of a master batch dispersed in a low-density polyethylene resin.

13. 2. The flame retardant polypropylene resin composition of claim 1, further comprising at least one additive selected from the group consisting of neutralizing agents, slip agents, antiblocking agents, fillers, weather stabilizers, antistatic agents, activators, nucleating agents, and dyes.

14. A flame-retardant polypropylene resin molded product produced by molding the flame-retardant polypropylene resin composition according to any one of claims 1 to 13.

15. The flame-retardant polypropylene resin molded article according to claim 14, which satisfies the V0 standard when measured according to the UL94 vertical test method based on a thickness of 1.5 mm.

16. 15. The flame-retardant polypropylene resin molded article according to claim 14, which satisfies the condition of 1000 hours or more in a flame retardant elution resistance test at a temperature of 85°C and a relative humidity of 85%.

17. The flame-retardant polypropylene resin molded article according to claim 14, which is a home appliance or an automobile part.

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