Polypropylene composite material as well as preparation method and application thereof

Abstract

The invention discloses a polypropylene composite material as well as a preparation method and application thereof. The polypropylene composite material comprises the following components in parts by weight: 65-110 parts of polypropylene and 0.5-12 parts of carbon aerogel, the specific surface area of the carbon aerogel is 1500-4000 m < 2 > / g. In the polypropylene system, the carbon aerogel with the specific specific surface area can quickly adsorb a large amount of volatile matters (such as C10-26 organic alkane substances) and can also reduce light reflection, and the interfacial tension between the carbon aerogel with the specific specific surface area and polypropylene is low, so that the carbon aerogel is not easy to agglomerate and is uniformly dispersed in the system; therefore, the odor of the polypropylene composite material is reduced, and the blackness of the polypropylene composite material is improved.

Description

Technical Field

[0001] This invention relates to the field of polymer materials technology, and more specifically, to a polypropylene composite material, its preparation method, and its application. Background Technology

[0002] Among the many types of automotive plastics, polypropylene (PP) is the primary type used, accounting for more than one-third of all automotive plastics. It is widely used in the manufacture of dashboards, center consoles, gear shifters, air conditioning controllers, door panels, pillars, side panels, bumpers, and other components. The core advantages of polypropylene as an automotive plastic lie in its lightweight, low cost, ease of processing, and modifiability. However, the odorous substances produced during polypropylene processing due to molecular chain breakage have limited its application in high-end models due to odor issues. Therefore, the development of low-odor polypropylene materials is urgently needed.

[0003] In addition, for black automotive parts made of polypropylene, high blackness polypropylene can reduce the manufacturing process and cost of black automotive parts. For example, the higher the blackness of polypropylene, the less black primer is needed when manufacturing the center console frame, and a clear varnish can be applied directly, thus reducing the manufacturing process and cost of the center console frame. Also, the higher the blackness of polypropylene, the less likely the gear shift cover will show scratches or turn white due to insufficient blackness in its high-frequency contact areas with users, thus not affecting the texture of the gear shift cover.

[0004] Therefore, developing a polypropylene composite material with low odor and high blackness is of great significance. Summary of the Invention

[0005] The purpose of this invention is to overcome the shortcomings of the prior art and provide a polypropylene composite material, its preparation method, and its application.

[0006] To achieve the above objectives, the technical solution adopted by the present invention is as follows: In a first aspect, the present invention provides a polypropylene composite material comprising the following components in parts by weight: 65-110 parts polypropylene and 0.5-12 parts carbon aerogel. The specific surface area of ​​the carbon aerogel is 1500-4000 m². 2 / g.

[0007] In polypropylene systems, carbon aerogels with a specific surface area can quickly and massively adsorb volatiles (such as C10-26 organic alkanes) and reduce light reflection. Moreover, the low interfacial tension between carbon aerogels with a specific surface area and polypropylene makes it difficult for carbon aerogels to agglomerate and allows them to be uniformly dispersed in the system, thereby reducing the odor of polypropylene composites and improving the blackness of polypropylene composites.

[0008] Preferably, the specific surface area of ​​the carbon aerogel is 1500 m². 2 / g、2000m 2 / g、2500m 2 / g、3000m 2 / g、3500m 2 / g、4000m 2 The range of one or both of the values ​​in / g.

[0009] More preferably, the specific surface area of ​​the carbon aerogel is 2000-3000 m². 2 / g.

[0010] In this invention, the specific surface area of ​​the carbon aerogel is measured by referring to the ISO 9277:2010 standard.

[0011] Preferably, the average particle size of the carbon aerogel is a range of one or any two of 400 μm, 500 μm, 600 μm, 700 μm, 800 μm, 900 μm, and 1000 μm.

[0012] Preferably, the average particle size of the carbon aerogel is 400-1000 μm.

[0013] More preferably, the carbon aerogel has an average particle size of 500-900 μm.

[0014] In this invention, the method for measuring the average particle size of the carbon aerogel is as follows: the average particle size of the carbon aerogel is measured in accordance with the national standard GB / T 3780.17-2017.

[0015] Preferably, the porosity of the carbon aerogel is 80%, 81%, 81.5%, 82%, 82.5%, 83%, 83.5%, 84%, 84.5%, 85%, 85.5%, 86%, 86.5%, 87%, 87.5%, 88%, 88.5%, 89%, 89.5%, 90%, 90.5%, 91%, 91.5%, 92%, 92%. The range of values ​​for one or any two of the following: 0.5%, 93%, 93.5%, 94%, 94.5%, 95%, 95.5%, 96%, 96.5%, 97%, 97.5%, 98%, 98.5%, 99%, 99.1%, 99.2%, 99.3%, 99.4%, 99.5%, 99.6%, 99.7%, 99.8%, and 99.9%.

[0016] More preferably, the porosity of the carbon aerogel is 80%-99.9%.

[0017] In this invention, the method for measuring the porosity of the carbon aerogel is as follows: the porosity of the carbon aerogel is measured in accordance with the national standard GB / T21650.1-2008.

[0018] In this invention, the carbon aerogel can be obtained through commercial purchases or prepared using conventional methods in the art.

[0019] Preferably, the carbon aerogel is prepared by mixing polyphenols, aldehydes, surfactants, solvents and catalysts, aging by heating, removing the solvent, and carbonizing at high temperature to obtain the carbon aerogel.

[0020] In this invention, the polyphenols include, but are not limited to, at least one of catechol, resorcinol, hydroquinone, and phloroglucinol, preferably resorcinol; the aldehydes include, but are not limited to, at least one of formaldehyde, paraformaldehyde, trioxane, methylformaldehyde, acetaldehyde, propionaldehyde, and butyraldehyde, preferably acetaldehyde; the surfactants include, but are not limited to, at least one of polyvinylpyrrolidone, hexadecyltrimethylammonium bromide, hexadecyltrimethylammonium chloride, sodium dodecyl sulfate, and sodium hexadecylbenzenesulfonate, preferably polyvinylpyrrolidone.

[0021] More preferably, the mass ratio of the polyphenols, aldehydes, and surfactants is (250-650):350:1.

[0022] More preferably, the mass ratio of the polyphenol, aldehyde compound, and surfactant is one or any two of the following: 250:350:1, 280:350:1, 300:350:1, 330:350:1, 350:350:1, 400:350:1, 450:350:1, 490:350:1, 500:350:1, 550:350:1, 600:350:1, 630:350:1, and 650:350:1.

[0023] More preferably, the mass ratio of the polyphenol, aldehyde compound, and surfactant is (280-630):350:1, specifically (250-500):350:1.

[0024] More preferably, the solvent is water.

[0025] More preferably, the catalyst is acetic acid.

[0026] More preferably, the catalyst accounts for 1-5% of the total mass of the polyphenols, aldehydes and surfactants.

[0027] More preferably, the aging temperature is one or any two of the following: 20°C, 25°C, 30°C, 35°C, 40°C, 45°C, 50°C, 55°C, 60°C, 65°C, 70°C, 75°C, 80°C, 85°C, 90°C, and 95°C.

[0028] More preferably, the temperature for aging by heating is 20-95°C.

[0029] More preferably, the high-temperature carbonization temperature is a range of one or any two of the following: 800℃, 820℃, 850℃, 880℃, 900℃, 920℃, 950℃, 980℃, 1000℃, 11020℃, 1050℃, 1080℃, 1100℃, 1120℃, 1150℃, 1180℃, and 1200℃.

[0030] More preferably, the high-temperature carbonization temperature is 800-1200℃.

[0031] Preferably, the raw materials for preparing the polypropylene composite material also include at least one of water and sodium bicarbonate.

[0032] More preferably, the raw materials for preparing the polypropylene composite material also include water and sodium bicarbonate, and the mass ratio of the carbon aerogel, water and sodium bicarbonate is 1:(0.1-8):(0.1-1).

[0033] More preferably, the raw materials for preparing the polypropylene composite material further include water and sodium bicarbonate, and the mass ratio of the carbon aerogel, water and sodium bicarbonate is 1:1:0.1, 1:2:0.1, 1:5.5:0.1, 1:6:0.1, 1:7:0.1, 1:8:0.1, 1:1:0.2, 1:2:0.2, 1:5.5:0.2, 1:6:0.2, 1:7:0.2, 1:8:0.2, or 1:1:0. 3. The range of one or any two of the following: 1:2:0.3, 1:5.5:0.3, 1:6:0.3, 1:7:0.3, 1:8:0.3, 1:1:0.4, 1:2:0.4, 1:5.5:0.4, 1:6:0.4, 1:7:0.4, 1:8:0.4, 1:1:0.5, 1:2:0.5, 1:5.5:0.5, 1:6:0.5, 1:7:0.5, 1:8:0.5.

[0034] More preferably, the raw materials for preparing the polypropylene composite material also include water and sodium bicarbonate, and the mass ratio of the carbon aerogel, water and sodium bicarbonate is 1:(1-6):(0.1-0.5), specifically 1:(1-5.5):(0.1-0.5).

[0035] More preferably, the raw materials for preparing the polypropylene composite material also include water and sodium bicarbonate, and the mass ratio of the carbon aerogel, water and sodium bicarbonate is 1:(1-2):(0.1-0.5).

[0036] More preferably, the raw materials for preparing the polypropylene composite material also include water and sodium bicarbonate, and the total weight parts of the carbon aerogel, water and sodium bicarbonate are one or any two of the following: 1 part, 2 parts, 3 parts, 3.5 parts, 4 parts, 5 parts, 6 parts, 7 parts, 8 parts, 9 parts, 10 parts, 11 parts, 12 parts, 13 parts, 14 parts, 15 parts, 16 parts, 17 parts, 18 parts, 19 parts, 20 parts, 21 parts, 22 parts, 23 parts, 24 parts, 25 parts, 26 parts, 27 parts, 28 parts, 29 parts, 30 parts, 31 parts, 32 parts and 33 parts.

[0037] More preferably, in the raw materials for preparing the polypropylene composite material, the total weight of the carbon aerogel, water and sodium bicarbonate is 1-33 parts.

[0038] More preferably, in the raw materials for preparing the polypropylene composite material, the total weight of the carbon aerogel, water and sodium bicarbonate is 2-28 parts.

[0039] Preferably, the odor level of the water is ≤1.5.

[0040] More preferably, the odor level of the water is 1.0-1.5.

[0041] More preferably, the odor level of the water is a range of one or both of the following: 1.0, 1.1, 1.2, 1.3, 1.4, and 1.5.

[0042] In this invention, the method for testing the odor level of water is as follows: according to the PV3900-2000 standard "Odor Detection of Automotive Interior Parts", 20g of water sample is placed in a 1L container, and the sample is heated at 80℃ for 2 hours using scheme 3. Five people evaluate the odor level, and five people conduct a retest evaluation. The odor level is divided into 1.0-6.0 points (accurate to one decimal place), corresponding to odor levels 1.0-6.0 respectively. The average value of the test results is taken.

[0043] Preferably, the polypropylene composite material further includes at least one of a toughening agent, a filler, an antioxidant, and a lubricant.

[0044] More preferably, the toughening agent has a melt flow rate of 0.2-20 g / 10 min measured at 190°C and 2.16 kg.

[0045] More preferably, the melt flow rate of the toughening agent measured at 190°C and 2.16 kg is one or any two of the following: 0.2 g / 10 min, 0.5 g / 10 min, 1 g / 10 min, 3 g / 10 min, 5 g / 10 min, 7 g / 10 min, 10 g / 10 min, 13 g / 10 min, 15 g / 10 min, 17 g / 10 min, and 20 g / 10 min.

[0046] In this invention, the melt flow rate (melt mass flow rate) of the toughening agent can be measured according to GB / T-3682-2000.

[0047] More preferably, the toughening agent includes at least one of polyolefin elastomer (POE), ethylene propylene diene monomer (EPDM), and hydrogenated styrene-butadiene block copolymer (SEBS).

[0048] More preferably, the toughening agent is in the range of one or any two of the following weight parts: 1 part, 2 parts, 3 parts, 4 parts, 5 parts, 6 parts, 7 parts, 8 parts, 9 parts, 10 parts, 11 parts, 12 parts, 13 parts, 14 parts, and 15 parts.

[0049] More preferably, the toughening agent is present in 1-15 parts by weight, specifically 1-10 parts.

[0050] More preferably, the filler includes at least one of talc, calcium carbonate, mica, whiskers, barium sulfate, and wollastonite.

[0051] More preferably, the weight parts of the filler are one or any two of the following: 1 part, 2 parts, 3 parts, 4 parts, 5 parts, 6 parts, 7 parts, 8 parts, 9 parts, 10 parts, 11 parts, 12 parts, 13 parts, 14 parts, 15 parts, 16 parts, 17 parts, 18 parts, 19 parts, 20 parts, 21 parts, 22 parts, 23 parts, 24 parts, and 25 parts.

[0052] More preferably, the filler is 1-25 parts by weight, specifically 2-20 parts.

[0053] More preferably, the antioxidant includes at least one of a primary antioxidant and a secondary antioxidant.

[0054] More preferably, the antioxidant is present in a weight range of 0.05 parts, 0.1 parts, 0.2 parts, 0.3 parts, 0.4 parts, 0.5 parts, 0.6 parts, 0.7 parts, 0.8 parts, 0.9 parts, 1 part, 1.1 parts, 1.2 parts, 1.3 parts, 1.4 parts, 1.5 parts, 1.6 parts, 1.7 parts, 1.8 parts, 1.9 parts, or 2 parts, or any combination thereof.

[0055] More preferably, the antioxidant is present in 0.05-2 parts by weight, specifically 0.05-1 parts.

[0056] More preferably, the main antioxidant is present in a weight fraction of 0.025-1 part, specifically 0.05-0.5 parts.

[0057] More preferably, the amount of the auxiliary antioxidant is 0.025-1 part by weight, specifically 0.05-0.5 parts.

[0058] More preferably, the primary antioxidant includes at least one of hindered phenolic antioxidants and hydroxylamine antioxidants.

[0059] More preferably, the hindered phenolic antioxidant includes at least one of antioxidant 1010, antioxidant 1076, antioxidant 3114, and antioxidant 1790.

[0060] More preferably, the hydroxylamine antioxidant includes at least one of antioxidant 420 and antioxidant 445.

[0061] More preferably, the auxiliary antioxidant includes phosphite antioxidants.

[0062] More preferably, the phosphite antioxidant includes at least one of antioxidant PEP-36, antioxidant 168, and antioxidant 626.

[0063] More preferably, the lubricant includes at least one of stearic acid lubricants and amide lubricants.

[0064] More preferably, the stearic acid lubricant includes at least one of stearic acid, calcium stearate, zinc stearate, and magnesium stearate.

[0065] More preferably, the amide lubricant includes at least one of oleamide and erucamide.

[0066] More preferably, the lubricant is in the range of one or any two of the following weight parts: 0.01 parts, 0.02 parts, 0.05 parts, 0.07 parts, 0.1 parts, 0.15 parts, 0.2 parts, 0.25 parts, 0.3 parts, 0.35 parts, 0.4 parts, 0.45 parts, 0.5 parts, 0.55 parts, 0.6 parts, 0.7 parts, 0.8 parts, 0.9 parts, and 1 part.

[0067] More preferably, the lubricant is present in a weight fraction of 0.01-1 parts, specifically 0.02-0.5 parts.

[0068] Preferably, the polypropylene is at least one of copolymer polypropylene and homopolymer polypropylene.

[0069] Preferably, the melt flow rate of the polypropylene measured at 230°C and 2.16 kg is 10-90 g / 10 min.

[0070] Preferably, the melt flow rate of the polypropylene measured at 230°C and 2.16 kg is one or any two of the following values: 10 g / 10 min, 12 g / 10 min, 15 g / 10 min, 17 g / 10 min, 20 g / 10 min, 25 g / 10 min, 30 g / 10 min, 35 g / 10 min, 40 g / 10 min, 45 g / 10 min, 50 g / 10 min, 55 g / 10 min, 60 g / 10 min, 65 g / 10 min, 70 g / 10 min, 75 g / 10 min, 80 g / 10 min, 85 g / 10 min, and 90 g / 10 min.

[0071] More preferably, the melt flow rate of the polypropylene measured at 230°C and 2.16 kg is 60-90 g / 10 min.

[0072] In this invention, the melt flow rate (melt mass flow rate) of the polypropylene can be measured according to GB / T 3682-2000.

[0073] Preferably, in the polypropylene composite material, the weight parts of polypropylene are within the range of one or any two of 65 parts, 70 parts, 75 parts, 80 parts, 85 parts, 90 parts, 95 parts, 100 parts, 105 parts, and 110 parts, and the weight parts of carbon aerogel are 0.5 parts, 0.6 parts, 0.7 parts, 0.8 parts, 0.9 parts, 1 part, 1.2 parts, 1.5 parts, 1.8 parts, 2 parts, 2.2 parts, 2.5 parts, 2.8 parts, 3 parts, 3.2 parts, 3.5 parts, 3.8 parts, ... The range of values ​​for one or any two of the following: 4, 4.2, 4.5, 4.8, 5, 5.2, 5.5, 5.8, 6, 6.2, 6.5, 6.8, 7, 7.2, 7.5, 7.8, 8, 8.2, 8.5, 8.8, 9, 9.2, 9.5, 9.8, 10, 10.2, 10.5, 10.8, 11, 11.2, 11.5, 11.8, and 12.

[0074] More preferably, the polypropylene composite material comprises the following components in parts by weight: 70-100 parts polypropylene and 1-8 parts carbon aerogel.

[0075] Preferably, based on the weight of the polypropylene composite material, the weight percentage of polypropylene is ≥45%, specifically 50%-99%.

[0076] Secondly, the present invention provides a method for preparing a polypropylene composite material, comprising the following steps: The components are mixed, extruded, and granulated to obtain the polypropylene composite material.

[0077] Preferably, the granulation process further includes at least one of washing and baking.

[0078] More preferably, the baking temperature is 80-120℃ and the baking time is 6-24h.

[0079] Preferably, a twin-screw extruder is used for the extrusion.

[0080] More preferably, the length-to-diameter ratio of the twin-screw extruder is (44-56):1.

[0081] More preferably, the temperature of the twin-screw extruder is 80-120℃ in zone one, 100-140℃ in zone two, 140-180℃ in zone three, 150-190℃ in zone four, 160-200℃ in zone five, and 180-220℃ starting from zone six.

[0082] More preferably, the vacuum degree of the vacuum orifice of the twin-screw extruder is ≤-0.08MPa.

[0083] Thirdly, the present invention provides an application of polypropylene composite material in black automotive parts.

[0084] In this invention, the black automotive parts include, but are not limited to, at least one of the following: center console frame, gear shift cover, instrument panel frame, air conditioning controller, bumper, side beam, door panel, and sub-panel.

[0085] Compared with the prior art, the beneficial effects of the present invention are as follows: In polypropylene systems, carbon aerogels with a specific surface area can quickly and massively adsorb volatiles (such as C10-26 organic alkanes) and reduce light reflection. Moreover, the low interfacial tension between carbon aerogels with a specific surface area and polypropylene makes it difficult for carbon aerogels to agglomerate and allows them to be uniformly dispersed in the system, thereby reducing the odor of polypropylene composites and improving the blackness of polypropylene composites. Detailed Implementation

[0086] To better illustrate the purpose, technical solution, and advantages of the present invention, the present invention will be further described below in conjunction with specific embodiments.

[0087] The experimental methods used in the following examples and comparative examples, unless otherwise specified, are generally performed under conventional conditions in the art or as recommended by the manufacturer. Unless otherwise specified, all raw materials and reagents used are commercially available from the general market. Furthermore, unless otherwise specified, "parts" and "%" refer to weight or mass.

[0088] The reagents used in the various embodiments and comparative examples of this invention are as follows: Polypropylene resin 1 (PP-1): Copolymer polypropylene resin, PP BX3900, SK Korea, with a melt flow rate of 60 g / 10 min at 230℃ and 2.16 kg. Polypropylene resin 2 (PP-2): Copolymer polypropylene resin, PP BX3920, SK Korea, with a melt flow rate of 90 g / 10 min at 230℃ and 2.16 kg. Polypropylene resin 3 (PP-3): Homopolymer polypropylene resin, PP HP500N, Basel, with a melt flow rate of 12 g / 10 min at 230°C and 2.16 kg. Polypropylene resin 4 (PP-4): Copolymer polypropylene resin, PPEP300M, Zhejiang Petrochemical, with a melt flow rate of 10g / 10min at 230℃ and 2.16kg. Carbon aerogel 1, specific surface area 2000 m² 2The carbon aerogel, with an average particle size of 500 μm and a porosity of 90%, was prepared by mixing resorcinol, acetaldehyde, polyvinylpyrrolidone, solvent (deionized water), and catalyst (acetic acid) for 1 h, aging at 80 °C for 30 h, adding deionized water and stirring for 6 h, drying at room temperature to remove the solvent (deionized water), and carbonizing at 1000 °C for 8 h under inert nitrogen protection, followed by grinding to obtain carbon aerogel 1 with an average particle size of 500 μm. The mass ratio of resorcinol, acetaldehyde, and polyvinylpyrrolidone was 350:350:1, and the catalyst (acetic acid) accounted for 2% of the total mass of resorcinol, acetaldehyde, and polyvinylpyrrolidone.

[0089] Carbon aerogel 2, specific surface area 3000 m² 2 The carbon aerogel 2, with an average particle size of 500 μm and a porosity of 93%, is prepared by mixing resorcinol, acetaldehyde, polyvinylpyrrolidone, solvent (deionized water), and catalyst (acetic acid) for 1 h, aging at 85 °C for 30 h, adding deionized water and stirring for 6 h, drying at room temperature to remove the solvent (deionized water), and carbonizing at 1050 °C for 8 h under inert nitrogen protection, followed by grinding to obtain a carbon aerogel 2 with an average particle size of 500 μm. The mass ratio of resorcinol, acetaldehyde, and polyvinylpyrrolidone is 490:350:1, and the mass of catalyst (acetic acid) accounts for 2% of the total mass of resorcinol, acetaldehyde, and polyvinylpyrrolidone.

[0090] Carbon aerogel 3, specific surface area 1500 m² 2 The carbon aerogel 3, with an average particle size of 500 μm and a porosity of 87%, is prepared by mixing resorcinol, acetaldehyde, polyvinylpyrrolidone, solvent (deionized water), and catalyst (acetic acid) for 1 h, aging at 75 °C for 30 h, adding deionized water and stirring for 6 h, drying at room temperature to remove the solvent (deionized water), and carbonizing at 950 °C for 8 h under inert nitrogen protection. The aerogel is then ground to obtain a carbon aerogel 3 with an average particle size of 500 μm. The mass ratio of resorcinol, acetaldehyde, and polyvinylpyrrolidone is 280:350:1, and the catalyst (acetic acid) accounts for 2% of the total mass of resorcinol, acetaldehyde, and polyvinylpyrrolidone.

[0091] Carbon aerogel 4, specific surface area 4000 m² 2The carbon aerogel, with an average particle size of 500 μm and a porosity of 97%, was prepared as follows: Resorcinol, acetaldehyde, polyvinylpyrrolidone, solvent (deionized water), and catalyst (acetic acid) were stirred and mixed for 1 hour, then aged at 91°C for 30 hours. Deionized water was added and stirred for 6 hours. The mixture was dried at room temperature to remove the solvent (deionized water), and then carbonized at 1120°C for 8 hours under inert nitrogen gas protection. Finally, it was ground to obtain carbon aerogel 4 with an average particle size of 500 μm. The mass ratio of resorcinol, acetaldehyde, and polyvinylpyrrolidone was 630:350:1, and the catalyst (acetic acid) accounted for 2% of the total mass of resorcinol, acetaldehyde, and polyvinylpyrrolidone.

[0092] Carbon aerogel 5, specific surface area 1000 m² 2 The carbon aerogel, with an average particle size of 500 μm and a porosity of 84%, was prepared as follows: Resorcinol, acetaldehyde, polyvinylpyrrolidone, solvent (deionized water), and catalyst (acetic acid) were stirred and mixed for 1 hour, then aged at 65°C for 30 hours. Deionized water was added and stirred for 6 hours. The mixture was dried at room temperature to remove the solvent (deionized water), and then carbonized at 850°C for 8 hours under inert nitrogen gas protection. Finally, it was ground to obtain carbon aerogel 5 with an average particle size of 500 μm. The mass ratio of resorcinol, acetaldehyde, and polyvinylpyrrolidone was 210:350:1, and the catalyst (acetic acid) accounted for 2% of the total mass of resorcinol, acetaldehyde, and polyvinylpyrrolidone.

[0093] Carbon aerogel 6, specific surface area 4500 m² 2 The carbon aerogel 6, with an average particle size of 500 μm and a porosity of 99%, is prepared by mixing resorcinol, acetaldehyde, polyvinylpyrrolidone, solvent (deionized water), and catalyst (acetic acid) for 1 h, aging at 95 °C for 30 h, adding deionized water and stirring for 6 h, drying at room temperature to remove the solvent (deionized water), and carbonizing at 1200 °C for 8 h under inert nitrogen protection, followed by grinding to obtain a carbon aerogel 6 with an average particle size of 500 μm. The mass ratio of resorcinol, acetaldehyde, and polyvinylpyrrolidone is 700:350:1, and the mass of catalyst (acetic acid) accounts for 2% of the total mass of resorcinol, acetaldehyde, and polyvinylpyrrolidone.

[0094] Carbon aerogel 7, specific surface area 2000 m² 2 / g, with an average particle size of 900μm and a porosity of 90%, is prepared by grinding and crushing carbon aerogel 9 to obtain carbon aerogel 7 with an average particle size of 900μm.

[0095] Carbon aerogel 8, specific surface area 2000 m² 2 / g, with an average particle size of 400μm and a porosity of 90%, is prepared by grinding and crushing carbon aerogel 9 to obtain carbon aerogel 8 with an average particle size of 400μm.

[0096] Carbon aerogel 9, specific surface area 2000 m² 2 The carbon aerogel 9, with an average particle size of 1000 μm and a porosity of 90%, was prepared by mixing resorcinol, acetaldehyde, polyvinylpyrrolidone, solvent (deionized water), and catalyst (acetic acid) for 1 h, aging at 80 °C for 30 h, adding deionized water and stirring for 6 h, drying at room temperature to remove the solvent (deionized water), and carbonizing at 1000 °C for 8 h under inert nitrogen protection. The aerogel was then screened to obtain a carbon aerogel 9 with an average particle size of 1000 μm. The mass ratio of resorcinol, acetaldehyde, and polyvinylpyrrolidone was 350:350:1, and the catalyst (acetic acid) accounted for 2% of the total mass of resorcinol, acetaldehyde, and polyvinylpyrrolidone.

[0097] Water 1: Water, odor level 1.0, obtained by selecting tap water after two-stage reverse osmosis; Water 2: Water, odor level 1.5, can be obtained by selecting tap water; Sodium bicarbonate: S818079, Shanghai Maclean's; Toughening agent: Polyolefin elastomer (POE), POE ENGAGE 7447, DOW Chemical (Dow Chemical Corporation, USA), with a melt flow rate of 5 g / 10 min at 190°C and 2.16 kg. Filler: Talc powder, TYT-777A, Tianyuan Chemical; Main antioxidant: hindered phenolic antioxidant, antioxidant 1010, commercially available; Co-antioxidant: Phosphite antioxidant, Antioxidant 168, commercially available; Lubricant: Stearic acid lubricant, zinc stearate, commercially available; In this invention, the melt flow rate (melt mass flow rate) of the polypropylene and / or toughening agent can be measured according to GB / T-3682-2000.

[0098] In this invention, the specific surface area of ​​the carbon aerogel is measured by referring to the ISO 9277:2010 standard.

[0099] In this invention, the method for measuring the average particle size of the carbon aerogel is as follows: the average particle size of the carbon aerogel is measured in accordance with the national standard GB / T 3780.17-2017.

[0100] In this invention, the method for measuring the porosity of the carbon aerogel is as follows: the porosity of the carbon aerogel is measured in accordance with the national standard GB / T21650.1-2008.

[0101] In this invention, the method for testing the odor level of water is as follows: according to the PV3900-2000 standard "Odor Detection of Automotive Interior Parts", 20g of water sample is placed in a 1L container, and the sample is heated at 80℃ for 2 hours using scheme 3. Five people evaluate the odor level, and five people conduct a retest evaluation. The odor level is divided into 1.0-6.0 points (accurate to one decimal place), corresponding to odor levels 1.0-6.0 respectively. The average value of the test results is taken.

[0102] Examples 1-19 and Comparative Examples 1-3 Examples 1-19 and Comparative Examples 1-3 provide different polypropylene composite materials, differing only in the type and amount of each component. By weight, Examples 1-19 and Comparative Examples 1-3 comprise the components shown in Table 1. The preparation methods of the polypropylene composite materials of Examples 1-19 and Comparative Examples 1-3 include the following steps: S1. First, mix carbon aerogel, water and sodium bicarbonate to obtain mixture-1, and set aside. S2. Mix polypropylene, toughening agent, primary antioxidant, secondary antioxidant, and lubricant using a high-speed mixer to obtain mixture-2, which is set aside. S3. Add mixture-2 to the main feed port of a twin-screw extruder (length-to-diameter ratio 48:1), add filler to the first side feed port, and add mixture-1 to the second side feed port. Mix, extrude, granulate, wash with water, and bake at 120℃ for 16 hours to obtain the polypropylene composite material. The temperature of the twin-screw extruder is 80°C in zone 1, 120°C in zone 2, 160°C in zone 3, 170°C in zone 4, 180°C in zone 5, and 200°C starting from zone 6. The vacuum degree of the twin-screw extruder's vacuum orifice is -0.08MPa. In the above preparation method, if there are any components that were not used in the embodiments and / or comparative examples, they can be directly deleted; Table 1. Weight parts of each component in polypropylene composite materials of Examples 1-19 Table 2 shows the weight parts of each component in the polypropylene composites of Comparative Examples 1-3. Performance testing The performance of the polypropylene composite materials of each embodiment and comparative example was tested, as follows: 1. Odor rating test: The PV3900-2000 standard for "Odor Testing of Automotive Interior Parts" was adopted. 20g of polypropylene composite material (granules) from each example or comparative example was placed in a 1L container and heated at 80℃ for 2 hours using Scheme 3. Five people evaluated the odor level, and five people conducted a retest. The odor level was divided into 1.0-6.0 points (accurate to one decimal place), with a higher score indicating a more unpleasant smell. The average value of the test results was taken. 2. C10-26 content test: Weigh 30g of polypropylene composite material (granules) from each example or comparative example and place them in a 10L sealed container. Heat the container in air at 65°C for 2 hours. Then, adsorb the gas in the container using an adsorption tube and perform component analysis using GC-MS. Calculate the total content (unit: μg / g) of C10-26 alkanes and their isomers in the polypropylene composite material, denoted as H. 10-26 (Unit: μg / g); The total content (unit: μg / g) of C12 alkanes and their isomers in the polypropylene composite material is denoted as H. 12 (Unit: μg / g); Among them, H 10-26 ≤1.0μg / g and H 12 ≤0.1μg / g is the acceptable standard; 3. Blackness Test: At 200℃, polypropylene composite material was injection molded into a 100mm x 100mm × 3mm sample. According to the standard ASTM D2244-16, the L value was tested using a colorimeter. The L value is used to characterize the blackness. The smaller the L value, the greater the blackness of the polypropylene composite material. The experimental results are shown in the table below: Table 3 Performance test results of polypropylene composite materials in each example and comparative example. As shown in Table 3, the polypropylene composite material of the present invention has both low odor and high blackness, wherein the odor level is ≤4.0 and H... 10-26 ≤1.0μg / g, H 12 ≤0.12μg / g, L value ≤24.

[0103] As can be seen from Examples 1-4 and Comparative Examples 1-3, in the polypropylene system, carbon aerogel with a specific surface area can quickly and massively adsorb volatiles (such as C10-26 organic alkanes), and can also reduce light reflection. Moreover, the low interfacial tension between carbon aerogel with a specific surface area and polypropylene makes it difficult for carbon aerogel to agglomerate and allows it to be uniformly dispersed in the system, thereby reducing the odor of polypropylene composites and improving the blackness of polypropylene composites.

[0104] As can be seen from Examples 1 and 5-7, by further controlling the particle size of carbon aerogel, carbon aerogel can adsorb volatiles (such as C10-26 organic alkanes) more quickly and in larger quantities. It can also reduce light reflection better and reduce the interfacial tension between carbon aerogel and polypropylene, so that carbon aerogel can be better dispersed uniformly in the system, thereby better reducing the odor of polypropylene composites and improving the blackness of polypropylene composites.

[0105] Comparing Examples 1, 11-13, and 17, it is evident that adding water and sodium bicarbonate to the raw materials for preparing the polypropylene composite material in Example 1 can better reduce the odor of the polypropylene composite material. This is because, with the addition of water and sodium bicarbonate, the water evaporates during the high-temperature melt extrusion process of the polypropylene composite material, carrying away volatile substances (such as C10-26 organic alkanes), thus further reducing the odor. Meanwhile, the sodium bicarbonate decomposes during the high-temperature melt extrusion process of the polypropylene composite material, generating gas that also carries away volatile substances (such as C10-26 organic alkanes), further contributing to the reduction of the odor. Based on this, and in conjunction with Examples 1 and 8-10, it is clear that further adjusting the mass ratio of carbon aerogel, water, and sodium bicarbonate can further reduce the odor of the polypropylene composite material.

[0106] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention and are not intended to limit the scope of protection of the present invention. Although the present invention has been described in detail with reference to preferred embodiments, those skilled in the art should understand that modifications or equivalent substitutions can be made to the technical solutions of the present invention without departing from the essence and scope of the technical solutions of the present invention.

Claims

1. A polypropylene composite material, characterized in that, The components include the following parts by weight: 65-110 parts polypropylene, 0.5-12 parts carbon aerogel; The specific surface area of ​​the carbon aerogel is 1500-4000 m². 2 / g.

2. The polypropylene composite material as described in claim 1, characterized in that, Includes at least one of the following (1)-(2): (1) The specific surface area of ​​the carbon aerogel is 2000-3000 m². 2 / g; (2) The porosity of the carbon aerogel is 80%-99.9%.

3. The polypropylene composite material as described in claim 1, characterized in that, The average particle size of the carbon aerogel is 400-1000 μm.

4. The polypropylene composite material as described in claim 1, characterized in that, The average particle size of the carbon aerogel is 500-900 μm.

5. The polypropylene composite material as described in claim 1, characterized in that, Includes at least one of the following (1)-(2): (1) The preparation method of the carbon aerogel is as follows: mix polyphenols, aldehydes, surfactants, solvents and catalysts, heat for aging, remove solvents, and carbonize at high temperature to obtain carbon aerogel. (2) The polypropylene composite material further includes at least one of water and sodium bicarbonate.

6. The polypropylene composite material as described in claim 5, characterized in that, Includes at least one of the following (1)-(3): (1) The polypropylene composite material further includes water and sodium bicarbonate, and the mass ratio of the carbon aerogel, water and sodium bicarbonate is 1:(1-2):(0.1-0.5); (2) The polypropylene composite material also includes water and sodium bicarbonate, and the total weight of the carbon aerogel, water and sodium bicarbonate is 2-28 parts. (3) The odor level of the water is ≤1.

5.

7. The polypropylene composite material as described in claim 1, characterized in that, Includes at least one of the following (1)-(2): (1) The polypropylene is at least one of copolymer polypropylene and homopolymer polypropylene; (2) The melt flow rate of the polypropylene measured at 230℃ and 2.16kg is 60-90g / 10min.

8. The polypropylene composite material as described in claim 1, characterized in that, The polypropylene composite material also includes at least one of toughening agent, filler, antioxidant, and lubricant.

9. A method for preparing a polypropylene composite material as described in any one of claims 1-8, characterized in that, Includes the following steps: The components are mixed, extruded, and granulated to obtain the polypropylene composite material.

10. The application of a polypropylene composite material as described in any one of claims 1-8 in black automotive parts.

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