Polypropylene resin composition and article produced therefrom

Abstract

A polypropylene resin composition according to the present invention comprises: about 100 parts by weight of a base material including about 15 to about 60 wt% of a first polypropylene resin having a melt flow index of about 1 to about 50 g / 10 min, and about 40 to about 85 wt% of a second polypropylene resin having a melt flow index of about 1,000 to about 1,400 g / 10 min; about 5 to about 25 parts by weight of an inorganic filler including at least one of talc or mica; and about 30 to about 100 parts by weight of glass fiber, and has a crystallization temperature (Tc) of about 127 to about 133°C. The polypropylene resin composition has excellent bending properties, impact resistance, rigidity, and appearance properties, as well as an excellent balance thereof.

Description

Polypropylene resin composition and molded article manufactured therefrom

[0001] The present invention relates to a polypropylene resin composition and a molded article manufactured therefrom. More specifically, the present invention relates to a polypropylene resin composition having excellent bending properties, impact resistance, rigidity, appearance properties, and a balance of these properties, and a molded article manufactured therefrom.

[0002]

[0003] Polypropylene resin has excellent chemical resistance, weather resistance, and processability, making it easy to manufacture into injection molded products, films, and blow molded products. It is a widely used material in fields such as electrical components, automobiles, and building materials.

[0004] However, polypropylene resin is prone to shrinkage due to crystallization. Consequently, when applied to injection molding using large molds, crystallization of the material can cause warping or distortion of the molded product, a drawback.

[0005] Therefore, there is a need to develop a polypropylene resin composition with excellent bending properties, impact resistance, rigidity, appearance properties, and a balance of these properties.

[0006] The background technology of the present invention is disclosed in Korean Patent No. 10-1425285, etc.

[0007]

[0008] The purpose of the present invention is to provide a polypropylene resin composition having excellent bending properties, impact resistance, rigidity, appearance properties, and a balance of these physical properties.

[0009] Another object of the present invention is to provide a molded article formed from the polypropylene resin composition.

[0010] The above and other objects of the present invention can all be achieved by the present invention described below.

[0011]

[0012] 1. One aspect of the present invention relates to a polypropylene resin composition. The polypropylene resin composition comprises: (A) about 100 parts by weight of a base material including about 15 to about 60 wt% of a first polypropylene resin having a melt-flow index of about 1 to about 50 g / 10 min as measured under conditions of 230°C and 2.16 kg load according to ASTM D1238; and (B) about 40 to about 85 wt% of a second polypropylene resin having a melt-flow index of about 1,000 to about 1,400 g / 10 min as measured under conditions of 230°C and 2.16 kg load according to ASTM D1238; (C) about 5 to about 25 parts by weight of an inorganic filler including at least one of talc and mica; And (D) about 30 to about 100 parts by weight of glass fiber; and characterized in that the crystallization temperature (Tc) measured from the exothermic peak that appears while increasing the temperature from 30°C to 300°C at a rate of 10°C / min in a nitrogen atmosphere using a differential scanning calorimeter (DSC), staying at 300°C for 1 minute, and then cooling at a rate of 10°C / min is about 127 to about 133°C.

[0013] 2. In the above 1 specific example, the first polypropylene resin may be a block polypropylene resin.

[0014] 3. In the above 1 or 2 specific examples, the first polypropylene resin may have a weight average molecular weight of about 150,000 to about 250,000 g / mol as measured by GPC (gel permeation chromatography).

[0015] 4. In the above specific examples 1 to 3, the second polypropylene resin may be a block polypropylene resin.

[0016] 5. In the above specific examples 1 to 4, the second polypropylene resin may have a weight average molecular weight of about 50,000 to about 90,000 g / mol as measured by GPC (gel permeation chromatography).

[0017] 6. In the above 1 to 5 specific examples, the talc may have an average particle size of about 0.5 to about 20 μm.

[0018] 7. In the above 1 to 6 specific examples, the mica may have an average particle size of about 0.5 to about 20 μm.

[0019] 8. In the above specific examples 1 to 7, the glass fiber may be surface-treated with an olefin-based surface treatment agent.

[0020] 9. In the above 1 to 8 specific examples, the weight ratio of the inorganic filler and the glass fiber may be about 1:2 to about 1:16.

[0021] 10. In the above 1 to 9 specific examples, when three corners of an injection molded specimen having a size of 15 cm × 40 cm × 15 mm are attached to the ground and left for 24 hours under conditions of a temperature of 23°C and a relative humidity of 50%, the length (height) of the remaining corner from the ground may be about 7 mm or less.

[0022] 11. In the above 1 to 10 specific examples, the polypropylene resin composition may have a notched Izod impact strength of about 9 to about 20 kgf·cm / cm of a 1 / 8" thick specimen measured according to ASTM D256.

[0023] 12. In the above 1 to 11 specific examples, the polypropylene resin composition has a tensile strength of about 890 to about 1,200 kgf / cm of a 3.2 mm thick specimen measured under conditions of 5 mm / min according to ASTM D638. 2 It could be.

[0024] 13. In the above 1 to 12 specific examples, the polypropylene resin composition has a flexural strength of about 1,200 to about 1,400 kgf / cm of a 6.4 mm thick specimen measured under conditions of 2.8 mm / min according to ASTM D790. 2 It could be.

[0025] 14. In the above 1 to 13 specific examples, the polypropylene resin composition has a flexural modulus of about 69,000 to about 80,000 kgf / cm of a 6.4 mm thick specimen measured under conditions of 2.8 mm / min according to ASTM D790. 2 It could be.

[0026] 15. Another aspect of the present invention relates to a molded article. The molded article is characterized in that it is formed from a polypropylene resin composition according to any one of 1 to 14.

[0027]

[0028] The present invention has the effect of providing a polypropylene resin composition having excellent bending properties, impact resistance, rigidity, appearance properties, and a balance of these physical properties, and a molded article formed therefrom.

[0029]

[0030] Hereinafter, the present invention will be described in detail as follows.

[0031] A polypropylene resin composition according to the present invention comprises (A) a first polypropylene resin; (B) a second polypropylene resin; (C) an inorganic filler; and (D) glass fiber.

[0032] In this specification, “a to b” indicating a numerical range is defined as “≥a and ≤b”.

[0033]

[0034] (A) First polypropylene resin

[0035] According to one specific example of the present invention, the first polypropylene resin can be applied together with the second polypropylene resin, an inorganic filler, and glass fiber, etc. to improve the warpage characteristics, impact resistance, rigidity, appearance characteristics, and physical property balance thereof of the polypropylene resin composition. A polypropylene resin having a melt-flow index of about 1 to about 50 g / 10 min, for example, about 5 to about 30 g / 10 min, measured under conditions of 230°C and 2.16 kg load according to ASTM D1238 can be used. When the flow index of the first polypropylene resin is less than about 1 g / 10 min, there is a concern that the rigidity, appearance characteristics, moldability, etc. of the polypropylene resin composition may deteriorate, and when it exceeds about 50 g / 10 min, there is a concern that the impact resistance, rigidity, etc. of the polypropylene resin composition may deteriorate.

[0036] In a specific example, the first polypropylene resin may be a block polypropylene resin. Here, the block polypropylene resin may be a block polypropylene resin composed of a homopolypropylene block and an ethylene-propylene copolymer block and / or a homopolyethylene block.

[0037] In a specific example, the first polypropylene resin may have a weight average molecular weight (Mw) measured by gel permeation chromatography (GPC) of about 150,000 to about 250,000 g / mol, for example, about 170,000 to about 230,000 g / mol. Within this range, the polypropylene resin composition may have excellent impact resistance, rigidity, and the like.

[0038] In a specific example, the first polypropylene resin may be included in an amount of about 15 to about 60 wt%, for example, about 20 to about 50 wt%, of 100 wt% of the base material composed of the first polypropylene resin and the second polypropylene resin. When the content of the first polypropylene resin is less than about 15 wt% of the base material, there is a concern that the impact resistance, appearance characteristics, etc. of the polypropylene resin composition may be deteriorated, and when it exceeds about 60 wt%, there is a concern that the rigidity, appearance characteristics, moldability, etc. of the polypropylene resin composition may be deteriorated.

[0039]

[0040] (B) Second polypropylene resin

[0041] According to one specific example of the present invention, the second polypropylene resin can be applied together with the first polypropylene resin, an inorganic filler, and glass fiber, etc. to improve the warpage characteristics, impact resistance, rigidity, appearance characteristics, and physical property balance thereof of the polypropylene resin composition. A polypropylene resin having a melt-flow index of about 1,000 to about 1,400 g / 10 min, for example, about 1,100 to about 1,300 g / 10 min, measured under conditions of 230°C and 2.16 kg load according to ASTM D1238 can be used. When the flow index of the second polypropylene resin is less than about 1,000 g / 10 min, there is a concern that the bending properties, appearance properties, moldability, etc. of the polypropylene resin composition may deteriorate, and when it exceeds about 1,400 g / 10 min, there is a concern that the impact resistance, rigidity, appearance properties, etc. of the polypropylene resin composition may deteriorate.

[0042] In a specific example, the second polypropylene resin may be a block polypropylene resin. Here, the block polypropylene resin may be a block polypropylene resin composed of a homopolypropylene block and an ethylene-propylene copolymer block and / or a homopolyethylene block.

[0043] In a specific example, the second polypropylene resin may have a weight average molecular weight (Mw) measured by gel permeation chromatography (GPC) of about 50,000 to about 90,000 g / mol, for example, about 60,000 to about 80,000 g / mol. Within this range, the appearance properties, moldability, etc. of the polypropylene resin composition may be excellent.

[0044] In a specific example, the second polypropylene resin may be included in an amount of about 40 to about 85 wt%, for example, about 50 to about 80 wt%, based on 100 wt% of the base material composed of the first polypropylene resin and the second polypropylene resin. When the content of the second polypropylene resin is less than about 40 wt%, based on 100 wt% of the base material, there is a concern that the rigidity, appearance characteristics, moldability, etc. of the polypropylene resin composition may be deteriorated, and when it exceeds about 85 wt%, there is a concern that the impact resistance, appearance characteristics, etc. of the polypropylene resin composition may be deteriorated.

[0045]

[0046] (C) Inorganic filler

[0047] According to one specific example of the present invention, an inorganic filler is applied together with a first polypropylene resin, a second polypropylene resin, and glass fiber, etc., to improve warpage characteristics, impact resistance, rigidity, appearance characteristics, and physical property balance of the polypropylene resin composition, and talc and / or mica may be used.

[0048] In a specific example, the talc may be a plate-shaped talc used in a typical thermoplastic resin composition, and may have an average particle size of about 0.5 to about 20 μm, for example, about 1 to about 10 μm, as measured by a particle size measuring device (Malvern Panalytical, Mastersizer 3000). Within this range, the impact resistance, appearance characteristics, etc. of the polypropylene resin composition may be excellent.

[0049] In a specific example, the mica may be plate-shaped or amorphous mica used in a typical thermoplastic resin composition, and may have an average particle size of about 0.5 to about 20 μm, for example, about 1 to about 10 μm, as measured by a particle size measuring device (Malvern mastersizer 3000). Within this range, the impact resistance, appearance characteristics, etc. of the polypropylene resin composition may be excellent.

[0050] In a specific example, the inorganic filler may be included in an amount of about 5 to about 25 parts by weight, for example, about 5 to about 20 parts by weight, based on about 100 parts by weight of the base material. If the content of the inorganic filler is less than about 5 parts by weight based on about 100 parts by weight of the base material, there is a concern that the bending properties, appearance properties, etc. of the polypropylene resin composition may deteriorate, and if it exceeds about 20 parts by weight, there is a concern that the impact resistance, rigidity, etc. of the polypropylene resin composition may deteriorate.

[0051]

[0052] (D) Glass fiber

[0053] According to one specific example of the present invention, glass fibers can be applied together with a first polypropylene resin, a second polypropylene resin, and an inorganic filler, etc., to improve warpage characteristics, impact resistance, rigidity, appearance characteristics, and balance of these physical properties of a polypropylene resin composition, and glass fibers used in a typical thermoplastic resin composition can be used.

[0054] In specific embodiments, the glass fibers may be in the form of fibers and may have various cross-sections such as circular, oval, rectangular, etc. For example, it may be preferable in terms of mechanical properties to use fibrous glass fibers having circular and / or rectangular cross-sections.

[0055] In a specific example, the glass fibers having a circular cross-section may have a cross-sectional diameter of about 5 to about 20 ㎛ as measured using a Scanning Electron Microscope (SEM) and a length before processing of about 2 to about 20 mm, and the glass fibers having a rectangular (flat) cross-section may have a cross-sectional aspect ratio (major axis of the cross-section / minor axis of the cross-section) as measured using a Scanning Electron Microscope (SEM) of about 1.5 to about 10, a minor axis of about 2 to about 10 ㎛, and a length before processing of 2 to 20 mm. In the above range, the rigidity, moldability, etc. of the polypropylene resin composition may be excellent.

[0056] In a specific example, the glass fiber may be surface-treated with an olefin-based surface treatment agent. In this case, the impact resistance, rigidity, and appearance properties of the polypropylene resin composition may be further improved.

[0057] In a specific example, the glass fiber may be included in an amount of about 30 to about 100 parts by weight, for example, about 40 to about 90 parts by weight, based on about 100 parts by weight of the base material. If the content of the glass fiber is less than about 30 parts by weight based on about 100 parts by weight of the base material, there is a concern that the impact resistance, rigidity, etc. of the polypropylene resin composition may be reduced, and if it exceeds about 100 parts by weight, there is a concern that the bending characteristics, appearance characteristics, etc. of the polypropylene resin composition may be reduced.

[0058] In a specific example, the weight ratio of the inorganic filler and the glass fiber (inorganic filler: glass fiber) may be from about 1:2 to about 1:16, for example from about 1:2.6 to about 1:13. In this range, the flexural properties, mechanical strength, appearance properties, etc. of the polypropylene resin composition may be more excellent.

[0059]

[0060] A polypropylene resin composition according to one embodiment of the present invention may further include additives included in conventional thermoplastic resin compositions. Examples of such additives include, but are not limited to, impact modifiers, flame retardants, anti-drop agents, antioxidants, stabilizers, release agents, nucleating agents, pigments, dyes, and mixtures thereof.

[0061] In a specific example, when the additive is used, the content may be about 0.001 to about 40 parts by weight, for example, about 0.1 to about 10 parts by weight, based on about 100 parts by weight of the base material.

[0062]

[0063] A polypropylene resin composition according to one specific example of the present invention may be in the form of pellets obtained by mixing the above components and melt-extruding them at about 180 to about 320°C, for example, about 240 to about 300°C, using a conventional twin-screw extruder.

[0064] In a specific example, the polypropylene resin composition may have a crystallization temperature (Tc) of about 127 to about 133°C, for example, about 128 to about 132°C, as measured from an exothermic peak that occurs while heating about 10 mg of a sample in a nitrogen atmosphere from 30°C to 300°C at a rate of 10°C / min, maintaining it at 300°C for 1 minute, and then cooling it at a rate of 10°C / min using a differential scanning calorimeter (DSC). When the crystallization temperature of the polypropylene resin composition is less than about 127°C, there is a concern that the moldability of the polypropylene resin composition may deteriorate, and when it exceeds about 133°C, there is a concern that the appearance characteristics of the polypropylene resin composition may deteriorate.

[0065] In a specific example, when the polypropylene resin composition is attached to the ground at three corners of an injection molded specimen measuring 15 cm × 40 cm × 15 mm and left for 24 hours under conditions of a temperature of 23°C and a relative humidity of 50%, the length (height) of the remaining corner from the ground may be about 7 mm or less, for example, about 1 to about 5 mm.

[0066] In a specific example, the polypropylene resin composition may have a notched Izod impact strength of about 9 to about 20 kgf·cm / cm, for example, about 10 to about 15 kgf·cm / cm, of a 1 / 8" thick specimen measured according to ASTM D256.

[0067] In a specific example, the polypropylene resin composition has a tensile strength of about 890 to about 1,200 kgf / cm of a 3.2 mm thick specimen measured under conditions of 5 mm / min according to ASTM D638. 2 , for example, about 900 to about 1,150 kgf / cm 2 It could be.

[0068] In a specific example, the polypropylene resin composition has a flexural strength of about 1,200 to about 1,400 kgf / cm of a 6.4 mm thick specimen measured under conditions of 2.8 mm / min according to ASTM D790. 2 , for example, about 1,210 to about 1,350 kgf / cm 2 It could be.

[0069] In a specific example, the polypropylene resin composition has a flexural modulus of about 69,000 to about 80,000 kgf / cm of a 6.4 mm thick specimen measured under conditions of 2.8 mm / min according to ASTM D790. 2 , for example, about 70,000 to about 79,000 kgf / cm 2 It could be.

[0070]

[0071] The molded article according to the present invention is formed from the polypropylene resin composition. The polypropylene resin composition can be manufactured in the form of pellets, and the manufactured pellets can be manufactured into various molded articles (products) through various molding methods such as injection molding, extrusion molding, vacuum molding, and casting molding. Such molding methods are well known to those skilled in the art to which the present invention pertains.

[0072] In a specific example, the molded product has excellent bending properties, impact resistance, rigidity, appearance properties, and balance of these properties, and is therefore useful as an interior / exterior material for home appliances, a building material, a housing material for office equipment, etc.

[0073]

[0074] Hereinafter, the present invention will be described in more detail through examples; however, these examples are for the purpose of explanation only and should not be construed as limiting the present invention.

[0075]

[0076] Example

[0077] Below, the specifications of each component used in the examples and comparative examples are as follows.

[0078] (A) First polypropylene resin

[0079] (A1) Block polypropylene resin (B-PP, manufacturer: Polymirae, product name: EP5175, melt-flow index: approximately 10 g / 10 min, weight average molecular weight (Mw): approximately 200,000 g / mol) was used.

[0080] (A2) Block polypropylene resin (B-PP, manufacturer: Lotte Chemical, product name: B-310, melt-flow index: approximately 0.4 g / 10 min, weight average molecular weight (Mw): approximately 300,000 g / mol) was used.

[0081] (A3) Block polypropylene resin (B-PP, manufacturer: Lotte Chemical, product name: JSS-395N, melt-flow index: approximately 100 g / 10 min, weight average molecular weight (Mw): approximately 130,000 g / mol) was used.

[0082] (B) Second polypropylene resin

[0083] (B1) Block polypropylene resin (B-PP, manufacturer: Lotte Chemical, product name: FM1912, melt-flow index: approximately 1,200 g / 10 min, weight average molecular weight (Mw): approximately 70,000 g / mol) was used.

[0084] (B2) Block polypropylene resin (B-PP, manufacturer: Xiamen Keyuan Plastic Co., Ltd, product name: PP-500, melt-flow index: approximately 500 g / 10 min, weight average molecular weight (Mw): approximately 100,000 g / mol) was used.

[0085] (B3) Block polypropylene resin (B-PP, manufacturer: Xiamen Keyuan Plastic Co., Ltd, product name: PP-1500, melt-flow index: approximately 1,700 g / 10 min, weight average molecular weight (Mw): approximately 60,000 g / mol) was used.

[0086] (C) Inorganic filler

[0087] (C1) Talc (Manufacturer: KOCH, Product Name: KCM6300) was used.

[0088] (C2) Mica (Manufacturer: KOCH, Product Name: M1250) was used.

[0089] (D) Glass fiber

[0090] Glass fiber (manufacturer: Jushi, product name: 508C) was used.

[0091]

[0092] Examples 1 to 8 and Comparative Examples 1 to 10

[0093] Each of the above components was added in the amounts shown in Tables 1, 2, 3, and 4 below, and then extruded at about 250°C to produce pellets. The extrusion was performed using a twin-screw extruder with an L / D of 48 and a diameter of 75 mm. The manufactured pellets were dried at about 80°C for about 2 hours or more, and then injected using a 110-ton injection molding machine (molding temperature: about 210°C, mold temperature: about 50°C) to produce test pieces. The physical properties of the manufactured test pieces were evaluated using the following methods, and the results are shown in Tables 1, 2, 3, and 4 below.

[0094]

[0095] Method of measuring physical properties

[0096] (1) Crystallization temperature (Tc, unit: ℃): About 10 mg of the thermoplastic resin composition samples of the above examples and comparative examples were vacuum-dried at 80℃ for 4 hours, and then, using a differential scanning calorimeter (DSC, manufacturer: TA, device name: Q20), the temperature was increased from 30℃ to 300℃ at a rate of 10℃ / min in a nitrogen atmosphere, and after staying at 300℃ for 1 minute, the crystallization temperature was measured from the exothermic peak that appeared while cooling at a rate of 10℃ / min.

[0097] (2) Warpage evaluation (unit: mm): Three corners of an injection molded specimen measuring 15 cm × 40 cm × 15 mm were attached to the ground, and when left for 24 hours under conditions of a temperature of 23°C and a relative humidity of 50%, the length (height) of the remaining corner from the ground was measured.

[0098] (3) Notched Izod impact strength (unit: kgf·cm / cm): The notched Izod impact strength of a 1 / 8" thick specimen was measured according to ASTM D256.

[0099] (4) Tensile strength (unit: kgf / cm) 2 ): According to ASTM D638, the tensile strength of a 3.2 mm thick specimen was measured under the condition of 5 mm / min.

[0100] (5) Flexural strength (unit: kgf / cm) 2 ): According to ASTM D790, the flexural strength of a 6.4 mm thick specimen was measured under the condition of 2.8 mm / min.

[0101] (6) Flexural modulus (unit: kgf / cm) 2 ): According to ASTM D790, the flexural modulus of a 6.4 mm thick specimen was measured under the condition of 2.8 mm / min.

[0102] (7) Appearance evaluation: After injection molding, the appearance was visually inspected. (○: No unusual colors or flow marks, ×: No unusual colors or flow marks)

[0103]

[0104] Example 1234 (A) (% by weight) (A1) 2030 5030 (A2) ---- (A3) ---- (B) (% by weight) (B1) 8070 5070 (B2) ---- (B3) ---- (C1) (parts by weight) 1515 15- (C2) (parts by weight) --- 15 (D) (parts by weight) 6060 6060 Crystallization temperature 128 129 130 129 Bending evaluation 4444 Notched Izod impact strength 1012 1313 Tensile strength 1,120 1,110 9 50 1,020 Flexural strength 1,30 0 1,28 0 1,23 0 1,280 Flexural modulus 75,200 74,800 74,200 73,600 Appearance evaluation ○○○○

[0105] * Weight parts: Weight parts per 100 weight parts of base material (A+B)

[0106]

[0107] Example 5678 (A) (% by weight) (A1) 30 30 30 30 (A2) ---- (A3) ---- (B) (% by weight) (B1) 70 70 70 70 (B2) ---- (B3) ---- (C1) (parts by weight) 520 15 15 (C2) (parts by weight) ---- (D) (parts by weight) 60 60 40 80 Crystallization temperature 128 13 11 28 132 Bending evaluation 53 43 Notched Izod impact strength 15 11 11 15 Tensile strength 1,1 20 1,0 8 0 9 20 1,150 Flexural strength 1,3 3 0 1,3 20 1,2 10 1,380 Flexural modulus 74,60 0 75,20 0 70,50 0 78,000 Appearance evaluation ○○○○

[0108] * Weight parts: Weight parts per 100 weight parts of base material (A+B)

[0109]

[0110] Comparative Example 12345 (A) (% by weight) (A1) 1070--30 (A2)--30--(A3)---30-(B) (% by weight) (B1) 90307070-(B2)----70 (B3)-----(C1) (parts by weight) 1515151515 (C2) (parts by weight)-----(D) (parts by weight) 6060606060 Crystallization temperature 135124128129134 Warpage evaluation 53449 Notched Izod Impact strength 81614816Tensile strength 1,1009409509801,090Flexural strength 1,2201,1801,1201,3201,270Flexural modulus 73,80068,20074,40066,30072,500Appearance evaluation ×××○×

[0111] * Weight parts: Weight parts per 100 weight parts of base material (A+B)

[0112]

[0113] Comparative Example 678910(A) (% by weight)(A1)3030303030(A2)-----(A3)-----(B) (% by weight)(B1)-70707070(B2)-----(B3)70----(C1) (parts by weight)152351515(C2) (parts by weight)-----(D) (parts by weight)60606020120Crystallization temperature137127128129135Bending evaluation3153310Notched Izod Impact strength 5158616 Tensile strength 8101,0208607601,320 Flexural strength 1,2501,2301,1508201,620 Flexural modulus 72,30070,50063,50056,00085,600 Appearance evaluation ××○○×

[0114] * Weight parts: Weight parts per 100 weight parts of base material (A+B)

[0115]

[0116] From the above results, it can be seen that the polypropylene resin composition of the present invention has a crystallization temperature of about 127 to about 133°C, and is excellent in bending properties (bending evaluation), impact resistance (notched Izod impact strength), rigidity (tensile strength, flexural strength, flexural modulus), appearance properties (appearance evaluation), and the balance of these physical properties.

[0117] On the other hand, when the content of the first polypropylene resin is less than the range of the present invention and the content of the second polypropylene resin is more than the range of the present invention (Comparative Example 1), it can be seen that impact resistance, appearance characteristics, etc. are deteriorated, and when the content of the first polypropylene resin is more than the range of the present invention and the content of the second polypropylene resin is less than the range of the present invention (Comparative Example 2), it can be seen that rigidity, appearance characteristics, etc. are deteriorated. When the first polypropylene resin (A2) having a flow index less than the range of the present invention is applied instead of the first polypropylene resin of the present invention (Comparative Example 3), it can be seen that rigidity, appearance characteristics, etc. are deteriorated, and when the first polypropylene resin (A3) having a flow index exceeding the range of the present invention is applied (Comparative Example 4), it can be seen that impact resistance, rigidity, etc. are deteriorated. When a second polypropylene resin (B2) having a flow index below the range of the present invention is applied instead of the second polypropylene resin of the present invention (Comparative Example 5), it can be seen that the bending properties, appearance properties, etc. are deteriorated, and when a second polypropylene resin (B3) having a flow index exceeding the range of the present invention is applied (Comparative Example 6), it can be seen that the impact resistance, rigidity, appearance properties, etc. are deteriorated.

[0118] In addition, in the case of Comparative Example 7, where the content of the inorganic filler is less than the range of the present invention, it can be seen that the bending characteristics, appearance characteristics, etc. are deteriorated, and in the case of Comparative Example 8, where the content of the inorganic filler is more than the range of the present invention, it can be seen that the impact resistance, rigidity, etc. are deteriorated, and in the case of Comparative Example 9, where the content of the glass fiber is less than the range of the present invention, it can be seen that the impact resistance, rigidity, etc. are deteriorated, and in the case of Comparative Example 10, where the content of the glass fiber is more than the range of the present invention, it can be seen that the bending characteristics, appearance characteristics, etc. are deteriorated.

[0119]

[0120] The present invention has been described with reference to exemplary embodiments. Those skilled in the art will appreciate that the present invention can be implemented in modified forms without departing from its essential characteristics. Therefore, the disclosed embodiments should be considered illustrative rather than limiting. The scope of the present invention is set forth in the claims, not the foregoing description, and all differences within the scope equivalent thereto should be construed as being encompassed by the present invention.

Claims

1. About 100 parts by weight of a base material comprising about 15 to about 60 wt% of a first polypropylene resin having a melt-flow index of about 1 to about 50 g / 10 min as measured under conditions of 230°C and 2.16 kg load according to ASTM D1238 and about 40 to about 85 wt% of a second polypropylene resin having a melt-flow index of about 1,000 to about 1,400 g / 10 min as measured under conditions of 230°C and 2.16 kg load according to ASTM D1238; About 5 to about 25 parts by weight of an inorganic filler comprising at least one of talc and mica; and Contains about 30 to about 100 parts by weight of glass fiber; A polypropylene resin composition characterized in that the crystallization temperature (Tc) is about 127 to about 133°C, measured from the exothermic peak that occurs when the temperature is increased from 30°C to 300°C at a rate of 10°C / min in a nitrogen atmosphere using a differential scanning calorimeter (DSC), and then the temperature is maintained at 300°C for 1 minute and then cooled at a rate of 10°C / min.

2. A polypropylene resin composition according to claim 1, characterized in that the first polypropylene resin is a block polypropylene resin.

3. A polypropylene resin composition according to claim 1 or 2, wherein the first polypropylene resin has a weight average molecular weight of about 150,000 to about 250,000 g / mol as measured by GPC (gel permeation chromatography).

4. A polypropylene resin composition according to any one of claims 1 to 3, wherein the second polypropylene resin is a block polypropylene resin.

5. A polypropylene resin composition according to any one of claims 1 to 4, wherein the second polypropylene resin has a weight average molecular weight of about 50,000 to about 90,000 g / mol as measured by GPC (gel permeation chromatography).

6. A polypropylene resin composition according to any one of claims 1 to 5, wherein the talc has an average particle size of about 0.5 to about 20 ㎛.

7. A polypropylene resin composition according to any one of claims 1 to 6, wherein the mica has an average particle size of about 0.5 to about 20 ㎛.

8. A polypropylene resin composition according to any one of claims 1 to 7, wherein the glass fiber is surface-treated with an olefin-based surface treatment agent.

9. A polypropylene resin composition according to any one of claims 1 to 8, wherein the weight ratio of the inorganic filler and the glass fiber is about 1:2 to about 1:

16.

10. A polypropylene resin composition according to any one of claims 1 to 9, wherein when three corners of an injection molded specimen measuring 15 cm × 40 cm × 15 mm are attached to the ground and left for 24 hours under conditions of a temperature of 23°C and a relative humidity of 50%, the length (height) of the remaining corner from the ground is about 7 mm or less.

11. A polypropylene resin composition according to any one of claims 1 to 10, characterized in that the polypropylene resin composition has a notched Izod impact strength of about 9 to about 20 kgf·cm / cm of a 1 / 8" thick specimen measured according to ASTM D256.

12. In any one of claims 1 to 11, the polypropylene resin composition has a tensile strength of about 890 to about 1,200 kgf / cm of a 3.2 mm thick specimen measured under conditions of 5 mm / min according to ASTM D638. 2 A polypropylene resin composition characterized by:

13. In any one of claims 1 to 12, the polypropylene resin composition has a flexural strength of about 1,200 to about 1,400 kgf / cm of a 6.4 mm thick specimen measured under conditions of 2.8 mm / min according to ASTM D790. 2 A polypropylene resin composition characterized by:

14. In any one of claims 1 to 13, the polypropylene resin composition has a flexural modulus of about 69,000 to about 80,000 kgf / cm of a 6.4 mm thick specimen measured under conditions of 2.8 mm / min according to ASTM D790. 2 A polypropylene resin composition characterized by:

15. A molded product characterized by being formed from a polypropylene resin composition according to any one of claims 1 to 14.