Polypropylene composite material as well as preparation method and application thereof

Abstract

The invention relates to the technical field of polymer composite materials, and discloses a polypropylene composite material as well as a preparation method and application thereof. The polypropylene composite material is prepared from the following raw materials: polypropylene resin I, polypropylene resin II, a toughening agent, an inorganic filler and a foaming agent, the melt index of the polypropylene resin I under the test condition of 230 DEG C / 2.16 kg is 1 g / 10 min to 100 g / 10 min; the melt index of the polypropylene resin II under the test condition of 230 DEG C / 2.16 kg is 500 g / 10 min to 2000 g / 10 min. After the polypropylene composite material provided by the invention is subjected to injection molding, the 60-degree glossiness is less than or equal to 1.3, the impact strength is greater than 20KJ / m < 2 >, the odor level is less than or equal to 3.5 level, the glossiness is low, the odor is low, the requirements of automobile internal components can be met, and the polypropylene composite material is applied to preparation of automobile interior parts.

Description

Technical Field

[0001] The present invention relates to the technical field of polymer composite materials, and in particular to a polypropylene composite material and a preparation method and application thereof. Background Art

[0002] Polypropylene is widely used in the automotive industry, especially in automotive interior and exterior decoration materials, due to its good processing performance and physical and chemical properties. Automotive interior parts, especially the dashboard, occupy a large part of the driver's field of vision. The dashboard made of high-gloss materials is prone to body reflection during driving. In addition, it will be reflected on the front windshield of the car, causing visual fatigue to the driver and posing a threat to driving safety. Therefore, reducing the glossiness of automotive interior parts is of great significance to improving driving safety.

[0003] At present, common automotive interior parts such as instrument panels, door panels, and auxiliary instrument panels are etched with specific leather grain surfaces. In addition to the functions of aesthetics and concealing defects, the fine leather grain structure on the surface greatly increases the surface roughness and reduces the surface gloss compared to the smooth surface. In addition to the structure of the leather grain itself, the factors that affect the gloss of the leather grain surface are also related to the injection molding process and the characteristics of the material itself.

[0004] CN 102807703 A discloses a low-gloss polypropylene composition and a preparation method thereof, wherein a matting agent with powdered rubber and grafted polypropylene as main components is added to reduce the gloss of the polypropylene material, but such matting agents generally have a strong odor and are not suitable for use in the preparation of automotive interior parts. CN 109679226 A discloses a low-gloss, low-odor, seamless polypropylene composite material for airbag instrument panels and a preparation method thereof, wherein a matting agent masterbatch containing inorganic fibers is added to reduce the gloss of the polypropylene material, but due to the poor compatibility of inorganic fibers and polypropylene, floating fibers are easily generated on the surface of the parts, affecting the aesthetic effect of the parts. Summary of the invention

[0005] The present invention aims to solve at least one of the above-mentioned technical problems existing in the prior art. To this end, one of the purposes of the present invention is to provide a polypropylene composite material; the second purpose of the present invention is to provide a method for preparing the polypropylene composite material; the third purpose of the present invention is to provide an application of the polypropylene composite material.

[0006] In order to achieve the above object, the technical solution adopted by the present invention is:

[0007] The first aspect of the present invention provides a polypropylene composite material, comprising the following preparation raw materials: polypropylene resin I, polypropylene resin II, toughening agent, inorganic filler and masterbatch;

[0008] The melt index of the polypropylene resin I under the test condition of 230°C / 2.16kg is 1g / 10min-100g / 10min;

[0009] The melt index of the polypropylene resin II under the test condition of 230° C. / 2.16 kg is 500 g / 10 min-2000 g / 10 min.

[0010] In some embodiments of the present invention, the melt index of the polypropylene resin I under the test condition of 230° C. / 2.16 kg is 20 g / 10 min-50 g / 10 min.

[0011] In some embodiments of the present invention, the melt index of the polypropylene resin II under the test condition of 230° C. / 2.16 kg is 1000 g / 10 min-1500 g / 10 min.

[0012] In some embodiments of the present invention, the polypropylene composite material further comprises the following preparation raw materials: a foaming agent, an antioxidant and a lubricant.

[0013] In some embodiments of the present invention, the polypropylene composite material comprises the following preparation raw materials by mass percentage:

[0014]

[0015] In some specific embodiments of the present invention, the polypropylene composite material includes the following preparation raw materials by mass percentage:

[0016]

[0017] In some embodiments of the present invention, the polypropylene resin I is selected from at least one of homopolypropylene and ethylene-propylene block copolymer polypropylene.

[0018] In some embodiments of the present invention, the polypropylene resin II is prepared by a method comprising the following steps:

[0019] Adding 0.05%-1% by mass of di-tert-butyl peroxyisopropylbenzene into homopolymerized polypropylene, and melt-extruded at 150-170° C. to obtain the polypropylene resin II;

[0020] The homopolypropylene has a melt index of 20 g / 10 min-30 g / 10 min under the test condition of 230° C. / 2.16 kg.

[0021] In the present invention, polypropylene resin II with a high melt index (500g / 10min-2000g / 10min, 230°C / 2.16kg) is used to enhance the formability of the polypropylene composite material, so that the composite material can be quickly filled into the fine structure of the mold during the injection molding process, so that the surface of the product can fully replicate the mold structure to the greatest extent. Polypropylene resin II is prepared by adding di-tert-butyl peroxyisopropylbenzene to homopolymer polypropylene, which has the characteristic of low odor compared with conventional peroxides.

[0022] In some embodiments of the present invention, the toughening agent has a melt index of 10 g / 10 min-40 g / 10 min under the test condition of 190° C. / 2.16 kg.

[0023] In some embodiments of the present invention, the toughening agent has a melt index of 30 g / 10 min-40 g / 10 min under the test condition of 190° C. / 2.16 kg.

[0024] In some embodiments of the present invention, the toughening agent is selected from at least one of ethylene-propylene rubber, ethylene-octene copolymer, ethylene-butene copolymer and ethylene-vinyl acetate.

[0025] In the present invention, unlike the conventional scheme for preparing low-gloss polypropylene composite materials, an elastomer with a relatively high melt index (10g / 10min-40g / 10min, 230°C / 2.16kg) is used as a toughening agent, and the toughening agent is used in conjunction with high melt index polypropylene resin II to improve the formability of the material and enhance the material's ability to replicate the fine structure of the mold.

[0026] In some embodiments of the present invention, the inorganic filler is selected from at least one of talc powder, calcium carbonate, wollastonite and mica powder.

[0027] In some embodiments of the present invention, the masterbatch is a masterbatch with polypropylene resin as a carrier.

[0028] In some embodiments of the present invention, the carbon black content of the masterbatch is 20wt%-60wt%.

[0029] In some embodiments of the present invention, the foaming agent is selected from at least one of azodicarbonamide, benzenesulfonylamide urea, and benzene disulfonyl hydrazide.

[0030] In the present invention, a small amount of foaming agent is added to the formula of the polypropylene composite material, so that the foaming agent generates a small amount of gas during the injection molding process of the composite material, forming certain pores inside and on the surface of the melt, and utilizing the rupture of the pores to increase the irregularity of the surface of the molding material and reduce the flatness, thereby increasing the diffuse reflection effect of the molding material surface on light and reducing the glossiness.

[0031] In some embodiments of the present invention, the lubricant is selected from at least one of stearate and silicone masterbatch.

[0032] In some embodiments of the present invention, the antioxidant is selected from at least one of hindered phenol antioxidants, thioester antioxidants, and phosphite antioxidants.

[0033] In some embodiments of the present invention, the antioxidant is a compound of a hindered phenol antioxidant and a phosphite antioxidant.

[0034] In some embodiments of the present invention, the mass ratio of the hindered phenol antioxidant to the phosphite antioxidant is 1:(0.8-1.2).

[0035] In some embodiments of the present invention, the hindered phenol antioxidant is selected from at least one of 2,6-di-tert-butyl-p-methylphenol (BHT), β-(3,5-di-tert-butyl-4-hydroxyphenyl) propionate (antioxidant 1076), pentaerythritol tetrakis[β-(3,5-di-tert-butyl-4-hydroxyphenyl) propionate (antioxidant 1010), N,N'-bis-(3-(3,5-di-tert-butyl-4-hydroxyphenyl) propionyl) hexanediamine (antioxidant 1098), and triethylene glycol bis[β-(3-tert-butyl-4-hydroxy-5-methylphenyl) propionate] (antioxidant 245).

[0036] In some embodiments of the present invention, the phosphite antioxidant includes at least one of diphenyl isooctyl phosphite (ODPP), tris[2,4-di-tert-butylphenyl]phosphite (antioxidant 168), bisphenol A phosphite, and triphenyl phosphite (TPP).

[0037] The second aspect of the present invention provides a method for preparing the polypropylene composite material according to the first aspect of the present invention, comprising the following steps:

[0038] Firstly, polypropylene resin I, polypropylene resin II, toughening agent and inorganic filler are mixed, and then foaming agent, antioxidant, lubricant and masterbatch are added to obtain a premix; the premix is ​​melt-mixed and extruded into granules through a twin-screw extruder to obtain the polypropylene composite material.

[0039] In some embodiments of the present invention, the polypropylene resin I, polypropylene resin II, toughening agent and inorganic filler are mixed at a rotation speed of 800-1500 r / min for 5-10 min.

[0040] In some embodiments of the present invention, the mixing speed after adding the foaming agent, antioxidant, lubricant and masterbatch is 800-1500r / min and the mixing time is 5-10min.

[0041] In some embodiments of the present invention, the temperatures of the feeding sections of the twin-screw extruder from the hopper to the die head are: first zone temperature: 160-165°C, second zone temperature: 160-165°C, third zone temperature: 160-165°C, fourth zone temperature: 160-165°C, fifth zone temperature: 160-170°C, sixth zone temperature: 170-180°C, seventh zone temperature: 180-190°C, eighth zone temperature: 190-200°C, ninth zone temperature: 200-210°C.

[0042] In some embodiments of the present invention, the head temperature of the twin-screw extruder is 200-210°C.

[0043] In some embodiments of the present invention, the screw speed of the twin-screw extruder is 300-600 r / min.

[0044] The third aspect of the present invention provides use of the polypropylene composite material described in the first aspect of the present invention in the preparation of automotive interior parts.

[0045] In some embodiments of the present invention, the automobile interior parts include an instrument panel, a door panel, and a sub-instrument panel.

[0046] Compared with the prior art, the present invention has the following beneficial effects:

[0047] 1) The polypropylene composite material provided by the present invention improves the formability of the material by adding a polypropylene resin substrate with a melt index of 500g / 10min-2000g / 10min (230°C / 2.16kg), so that the polypropylene composite material can quickly fill the fine structure of the mold grain during injection molding of parts, so that the surface of the plastic product can fully replicate the grain structure to the greatest extent, thereby reducing the surface gloss of the plastic product;

[0048] 2) The polypropylene composite material provided by the present invention is added with a toughening agent having a melt index of 10 g / 10 min-40 g / 10 min (230° C. / 2.16 kg), and the toughening agent is used in conjunction with a high melt index polypropylene resin to improve the ability of the polypropylene composite material to replicate mold grain, so as to achieve the effect of reducing gloss;

[0049] 3) The polypropylene composite material provided by the present invention, by adding a small amount of foaming agent, causes the material to foam during the melting process of injection molding to generate a small amount of gas, forms certain pores inside and on the surface of the melt, and partially ruptures the pores on the surface of the part to form an irregular surface flatness effect, thereby increasing the diffuse reflection effect of the part surface on light, so as to further reduce the surface gloss of the product;

[0050] 4) The preparation method of the polypropylene composite material provided by the present invention has simple steps and mild process conditions and is suitable for industrial use;

[0051] 5) After injection molding, the polypropylene composite material provided by the present invention has a 60° glossiness of ≤1.3 and an impact strength of >20KJ / m 2 , odor level ≤3.5, low gloss, low odor, can meet the requirements of automotive interior components, and is used in the preparation of automotive interior parts. BRIEF DESCRIPTION OF THE DRAWINGS

[0052] Figure 1 This is the injection-molded leather grain pattern of the polypropylene composite material in the embodiment. DETAILED DESCRIPTION

[0053] The present invention is further described in detail below by specific examples. Unless otherwise specified, the raw materials, reagents or devices used in the examples and comparative examples can be obtained from conventional commercial sources or can be obtained by prior art methods. Unless otherwise specified, the experiments or test methods are conventional methods in the art.

[0054] The raw material information used in the following examples and comparative examples is shown in Table 1 below:

[0055] Table 1 Information of raw materials used in the examples and comparative examples

[0056]

[0057]

[0058] in:

[0059] 1) The melt index of polypropylene resin IPP EP548R under the test conditions of 230°C / 2.16kg is 26g / 10min;

[0060] 2) The melting index of homopolypropylene PP Z30S under the test condition of 230°C / 2.16kg is 26g / 10min, and polypropylene resin II is prepared by melt extrusion of homopolypropylene PP Z30S and 0.08wt% of di-tert-butyl peroxyisopropylbenzene at 150-170°C, and the melting index under the test condition of 230°C / 2.16kg is 1500g / 10min;

[0061] 3) Polypropylene resin III is prepared by melt extrusion of homopolypropylene PP Z30S and 0.08% by mass of 2,5-dimethyl-2,5-bis(tert-butylperoxy)hexane at 150-170° C., and has a melt index of 1400 g / 10 min under the test condition of 230° C. / 2.16 kg;

[0062] 4) The melting index of toughener POE8730L under the test condition of 190°C / 2.16kg is 30g / 10min; the melting index of POE565 under the test condition of 190°C / 2.16kg is 5g / 10min;

[0063] 5) Masterbatch XP6622A uses polypropylene resin as a carrier and has a carbon black content of 40wt%.

[0064] Example 1

[0065] This example prepares a polypropylene composite material, and the raw materials are shown in Table 2:

[0066] Table 2 Composition of raw materials of polypropylene composite material in Example 1

[0067]

[0068]

[0069] The preparation method of the polypropylene composite material comprises the following steps:

[0070] First, polypropylene resin I, polypropylene resin II, toughening agent and inorganic filler are stirred and mixed at a speed of 1000 r / min for 10 minutes, and then a foaming agent, an antioxidant, a lubricant and a masterbatch are added, and the stirring and mixing is continued at a speed of 1000 r / min for 10 minutes to obtain a premix; the premix is ​​added from the main feeding port of a twin-screw extruder, melt-mixed, extruded and granulated to obtain a polypropylene composite material, wherein the temperatures of the feeding sections of the twin-screw extruder are set to 160°C, 160°C, 160°C, 160°C, 165°C, 170°C, 180°C, 190°C, and 200°C, the head temperature is 210°C, and the screw speed is 500 r / min.

[0071] Example 2

[0072] This example prepares a polypropylene composite material, and the raw materials are shown in Table 3:

[0073] Table 3 Composition of raw materials of polypropylene composite material in Example 2

[0074]

[0075] The preparation method of the polypropylene composite material comprises the following steps:

[0076] First, polypropylene resin I, polypropylene resin II, toughening agent and inorganic filler are stirred and mixed at a speed of 1000 r / min for 10 minutes, and then a foaming agent, an antioxidant, a lubricant and a masterbatch are added, and the stirring and mixing is continued at a speed of 1000 r / min for 10 minutes to obtain a premix; the premix is ​​added from the main feeding port of a twin-screw extruder, melt-mixed, extruded and granulated to obtain a polypropylene composite material, wherein the temperatures of the feeding sections of the twin-screw extruder are set to 160°C, 160°C, 160°C, 160°C, 165°C, 170°C, 180°C, 190°C, and 200°C, the head temperature is 210°C, and the screw speed is 500 r / min.

[0077] Example 3

[0078] This example prepares a polypropylene composite material, and the raw materials are shown in Table 4:

[0079] Table 4 Composition of raw materials of polypropylene composite material in Example 3

[0080]

[0081] The preparation method of the polypropylene composite material comprises the following steps:

[0082] First, polypropylene resin I, polypropylene resin II, toughening agent and inorganic filler are stirred and mixed at a speed of 1000 r / min for 10 minutes, and then a foaming agent, an antioxidant, a lubricant and a masterbatch are added, and the stirring and mixing is continued at a speed of 1000 r / min for 10 minutes to obtain a premix; the premix is ​​added from the main feeding port of a twin-screw extruder, melt-mixed, extruded and granulated to obtain a polypropylene composite material, wherein the temperatures of the feeding sections of the twin-screw extruder are set to 160°C, 160°C, 160°C, 160°C, 165°C, 170°C, 180°C, 190°C, and 200°C, the head temperature is 210°C, and the screw speed is 500 r / min.

[0083] Comparative Example 1

[0084] This comparative example prepares a polypropylene composite material, and the raw materials for preparation are shown in Table 5:

[0085] Table 5 Composition of raw materials of polypropylene composite material in comparative example 1

[0086]

[0087]

[0088] The preparation method of the polypropylene composite material comprises the following steps:

[0089] First, polypropylene resin I, toughening agent and inorganic filler are stirred and mixed at a speed of 1000 r / min for 10 minutes, and then antioxidant, lubricant and masterbatch are added, and stirring and mixing is continued at a speed of 1000 r / min for 10 minutes to obtain a premix; the premix is ​​added from the main feeding port of a twin-screw extruder, melt-mixed, extruded and granulated to obtain a polypropylene composite material, wherein the temperatures of the feeding sections of the twin-screw extruder are set to 160°C, 160°C, 160°C, 160°C, 165°C, 170°C, 180°C, 190°C, and 200°C, the head temperature is 210°C, and the screw speed is 500 r / min.

[0090] Comparative Example 2

[0091] This comparative example prepares a polypropylene composite material, and the raw materials for preparation are shown in Table 6:

[0092] Table 6 Composition of raw materials of polypropylene composite material in comparative example 2

[0093]

[0094] The preparation method of the polypropylene composite material comprises the following steps:

[0095] First, polypropylene resin I, polypropylene resin II, toughening agent and inorganic filler are stirred and mixed at a speed of 1000 r / min for 10 minutes, and then antioxidant, lubricant and masterbatch are added, and stirring and mixing is continued at a speed of 1000 r / min for 10 minutes to obtain a premix; the premix is ​​added from the main feeding port of a twin-screw extruder, melt-mixed, extruded and granulated to obtain a polypropylene composite material, wherein the temperatures of the feeding sections of the twin-screw extruder are set to 160°C, 160°C, 160°C, 160°C, 165°C, 170°C, 180°C, 190°C, and 200°C, the head temperature is 210°C, and the screw speed is 500 r / min.

[0096] Comparative Example 3

[0097] This comparative example prepares a polypropylene composite material, and the raw materials for preparation are shown in Table 7:

[0098] Table 7 Composition of raw materials of polypropylene composite material in comparative example 3

[0099]

[0100] The preparation method of the polypropylene composite material comprises the following steps:

[0101] First, polypropylene resin I, polypropylene resin II, toughening agent and inorganic filler are stirred and mixed at a speed of 1000 r / min for 10 minutes, and then antioxidant, lubricant and masterbatch are added, and stirring and mixing is continued at a speed of 1000 r / min for 10 minutes to obtain a premix; the premix is ​​added from the main feeding port of a twin-screw extruder, melt-mixed, extruded and granulated to obtain a polypropylene composite material, wherein the temperatures of the feeding sections of the twin-screw extruder are set to 160°C, 160°C, 160°C, 160°C, 165°C, 170°C, 180°C, 190°C, and 200°C, the head temperature is 210°C, and the screw speed is 500 r / min.

[0102] Comparative Example 4

[0103] This comparative example prepares a polypropylene composite material, and the raw materials for preparation are shown in Table 8:

[0104] Table 8 Composition of raw materials of polypropylene composite material in comparative example 4

[0105]

[0106]

[0107] The preparation method of the polypropylene composite material comprises the following steps:

[0108] First, polypropylene resin I, polypropylene resin II, toughening agent and inorganic filler are stirred and mixed at a speed of 1000 r / min for 10 minutes, and then antioxidant, lubricant and masterbatch are added, and stirring and mixing is continued at a speed of 1000 r / min for 10 minutes to obtain a premix; the premix is ​​added from the main feeding port of a twin-screw extruder, melt-mixed, extruded and granulated to obtain a polypropylene composite material, wherein the temperatures of the feeding sections of the twin-screw extruder are set to 160°C, 160°C, 160°C, 160°C, 165°C, 170°C, 180°C, 190°C, and 200°C, the head temperature is 210°C, and the screw speed is 500 r / min.

[0109] Comparative Example 5

[0110] This comparative example prepares a polypropylene composite material, and the raw materials for preparation are shown in Table 9:

[0111] Table 9 Composition of raw materials of polypropylene composite material in comparative example 5

[0112]

[0113] The preparation method of the polypropylene composite material comprises the following steps:

[0114] First, polypropylene resin I, polypropylene resin II, toughening agent and inorganic filler are stirred and mixed at a speed of 1000 r / min for 10 minutes, and then antioxidant, lubricant and masterbatch are added, and stirring and mixing is continued at a speed of 1000 r / min for 10 minutes to obtain a premix; the premix is ​​added from the main feeding port of a twin-screw extruder, melt-mixed, extruded and granulated to obtain a polypropylene composite material, wherein the temperatures of the feeding sections of the twin-screw extruder are set to 160°C, 160°C, 160°C, 160°C, 165°C, 170°C, 180°C, 190°C, and 200°C, the head temperature is 210°C, and the screw speed is 500 r / min.

[0115] Comparative Example 6

[0116] This comparative example prepares a polypropylene composite material, and the raw materials for preparation are shown in Table 10:

[0117] Table 10 Composition of raw materials of polypropylene composite material in comparative example 6

[0118]

[0119] The preparation method of the polypropylene composite material comprises the following steps:

[0120] First, polypropylene resin I, polypropylene resin II, toughening agent and inorganic filler are stirred and mixed at a speed of 1000 r / min for 10 minutes, and then antioxidant, lubricant and masterbatch are added, and stirring and mixing is continued at a speed of 1000 r / min for 10 minutes to obtain a premix; the premix is ​​added from the main feeding port of a twin-screw extruder, melt-mixed, extruded and granulated to obtain a polypropylene composite material, wherein the temperatures of the feeding sections of the twin-screw extruder are set to 160°C, 160°C, 160°C, 160°C, 165°C, 170°C, 180°C, 190°C, and 200°C, the head temperature is 210°C, and the screw speed is 500 r / min.

[0121] Comparative Example 7

[0122] This comparative example prepares a polypropylene composite material, and the raw materials for preparation are shown in Table 11:

[0123] Table 11 Composition of raw materials of polypropylene composite material in comparative example 7

[0124]

[0125] The preparation method of the polypropylene composite material comprises the following steps:

[0126] First, polypropylene resin I, polypropylene resin II, toughening agent and inorganic filler are stirred and mixed at a speed of 1000 r / min for 10 minutes, and then antioxidant, lubricant and masterbatch are added, and stirring and mixing is continued at a speed of 1000 r / min for 10 minutes to obtain a premix; the premix is ​​added from the main feeding port of a twin-screw extruder, melt-mixed, extruded and granulated to obtain a polypropylene composite material, wherein the temperatures of the feeding sections of the twin-screw extruder are set to 160°C, 160°C, 160°C, 160°C, 165°C, 170°C, 180°C, 190°C, and 200°C, the head temperature is 210°C, and the screw speed is 500 r / min.

[0127] Comparative Example 8

[0128] This comparative example prepares a polypropylene composite material, and the raw materials for preparation are shown in Table 12:

[0129] Table 12 Composition of raw materials of polypropylene composite material in comparative example 8

[0130]

[0131]

[0132] The preparation method of the polypropylene composite material comprises the following steps:

[0133] First, polypropylene resin I, polypropylene resin II, toughening agent and inorganic filler are stirred and mixed at a speed of 1000 r / min for 10 minutes, and then a foaming agent, an antioxidant, a lubricant and a masterbatch are added, and the stirring and mixing is continued at a speed of 1000 r / min for 10 minutes to obtain a premix; the premix is ​​added from the main feeding port of a twin-screw extruder, melt-mixed, extruded and granulated to obtain a polypropylene composite material, wherein the temperatures of the feeding sections of the twin-screw extruder are set to 160°C, 160°C, 160°C, 160°C, 165°C, 170°C, 180°C, 190°C, and 200°C, the head temperature is 210°C, and the screw speed is 500 r / min.

[0134] Performance Testing

[0135] The polypropylene composite materials in Examples 1-3 and Comparative Examples 1-8 were respectively injection molded. Figure 1 The polypropylene composite material injection molding leather grain style in the embodiment, the leather grain number is WGA001, and the 60° gloss, impact strength and odor of the style are tested respectively, and the reference standards are:

[0136] Gloss: Tested by reflection method according to ISO 2813-2014 "Paints and varnishes - Determination of specular gloss of non-metallic paint films at 20°, 60° and 85°";

[0137] Impact strength: Tested in accordance with ISO 180-2023 "Determination of Izod impact strength of plastics";

[0138] Odor: Test according to PV3900-2005 “Odor test for components inside the vehicle cab”.

[0139] Table 13 Performance test results of polypropylene composite materials in Examples 1-3 and Comparative Examples 1-8

[0140] Test items 60° gloss <![CDATA[Impact strength (KJ / m 2 )]]> odor Example 1 1.3 24 3.2 Example 2 1.1 22 3.1 Example 3 1.0 21 3.2 Comparative Example 1 2.5 42 3.1 Comparative Example 2 2.2 37 3.2 Comparative Example 3 2.0 32 3.1 Comparative Example 4 1.8 28 3.2 Comparative Example 5 1.5 19 3.2 Comparative Example 6 1.7 27 3.1 Comparative Example 7 1.5 26 3.2 Comparative Example 8 1.1 18 3.9

[0141] Table 13 shows the performance test results of the polypropylene composite materials in Examples 1-3 and Comparative Examples 1-8. It can be seen from Table 13 that after injection molding, the polypropylene composite materials prepared in Examples 1-3 have a 60° gloss of less than or equal to 1.3 and a cantilever beam impact strength of greater than 20 KJ / m 2 , the odor level is less than or equal to level 3.5, and the performance of these three aspects meets the requirements of automobile cab interior components.

[0142] Comparative Example 1 uses only ordinary low melt index polypropylene resin substrate, and the toughening agent is an elastomer with a relatively low melt index. The composite material has high impact strength and low odor, but the 60° gloss is high, which does not meet the low gloss requirement; Comparative Example 2 adds a small amount of high melt index polypropylene resin II on the basis of Comparative Example 1, and the 60° gloss of the material is reduced, but the impact strength is also reduced; Comparative Examples 3-5 further increase the amount of high melt index polypropylene resin II, and it can be seen that the gloss and impact strength of the composite material are linearly reduced, indicating that the addition of high melt index polypropylene resin II can improve the formability of the material, but because the impact strength of the high melt index polypropylene resin II itself is low, when the addition ratio exceeds 16wt%, the impact performance of the composite material is reduced to 20KJ / m 2 As follows; Comparative Example 6 reduces the amount of low melt index elastomer toughening agent on the basis of Comparative Example 4, and adds part of high melt index toughening agent. It can be seen that the impact strength of the material is basically not affected, and the glossiness is slightly reduced. After the low melt index toughening agent is completely replaced by the high melt index toughening agent in Comparative Example 7, the glossiness of the material is significantly reduced, indicating that the high melt index toughening agent has the effect of assisting the high melt index polypropylene resin II in improving the formability of the material; Examples 1-3 add foaming agent on the basis of Comparative Example 7, and as the amount of foaming agent increases, the glossiness of the material gradually decreases, indicating that the addition of the foaming agent forms certain micropores on the surface of the product, increases the surface roughness of the product, thereby increasing the diffuse reflection effect of the surface of the molding material on light and reducing the glossiness; The difference between Comparative Example 8 and Example 3 is that the peroxide used in the preparation of polypropylene resin II is different, resulting in the material having too strong odor, which cannot meet the requirement that the odor of the internal component material of the automobile cab is ≤3.5.

Claims

1. A polypropylene composite material, characterized in that: The method comprises the following preparation raw materials: polypropylene resin I, polypropylene resin II, toughening agent, inorganic filler and foaming agent; The melt index of the polypropylene resin I under the test condition of 230°C / 2.16kg is 1g / 10min-100g / 10min; The melt index of the polypropylene resin II under the test condition of 230° C. / 2.16 kg is 500 g / 10 min-2000 g / 10 min.

2. The polypropylene composite material according to claim 1, characterized in that: The polypropylene composite material also includes the following preparation raw materials: masterbatch, antioxidant and lubricant.

3. The polypropylene composite material according to claim 2, characterized in that: The polypropylene composite material comprises the following raw materials by mass percentage:

4. The polypropylene composite material according to claim 3, characterized in that: The polypropylene resin I is selected from at least one of homopolymer polypropylene and ethylene-propylene block copolymer polypropylene.

5. The polypropylene composite material according to claim 3, characterized in that: The polypropylene resin II is prepared by a method comprising the following steps: Adding 0.05%-1% by mass of di-tert-butyl peroxyisopropylbenzene into homopolymerized polypropylene, and melt-extruded at 150-170° C. to obtain the polypropylene resin II; The homopolypropylene has a melt index of 20 g / 10 min-30 g / 10 min under the test condition of 230° C. / 2.16 kg.

6. The polypropylene composite material according to claim 3, characterized in that: The melt index of the toughening agent under the test condition of 190°C / 2.16kg is 10g / 10min-40g / 10min; Preferably, the toughening agent is selected from at least one of ethylene-propylene rubber, ethylene-octene copolymer, ethylene-butene copolymer and ethylene-vinyl acetate.

7. The polypropylene composite material according to claim 3, characterized in that: The inorganic filler is selected from at least one of talc, calcium carbonate, wollastonite and mica powder; And / or, the carbon black content of the masterbatch is 20wt%-60wt%.

8. The polypropylene composite material according to claim 3, characterized in that: The foaming agent is selected from at least one of azodicarbonamide, benzenesulfonylamide urea and benzene disulfonyl hydrazide; And / or, the lubricant is selected from at least one of stearate and silicone masterbatch.

9. The method for preparing the polypropylene composite material according to any one of claims 1 to 8, characterized in that: The following steps are involved: Firstly, polypropylene resin I, polypropylene resin II, toughening agent and inorganic filler are mixed, and then foaming agent, antioxidant, lubricant and masterbatch are added to obtain a premix; the premix is ​​melt-mixed and extruded into granules through a twin-screw extruder to obtain the polypropylene composite material.

10. Use of the polypropylene composite material according to any one of claims 1 to 8 in the preparation of automotive interior parts.

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