Polypropylene composite material, preparation method thereof and vehicle part

Abstract

The invention discloses a polypropylene composite material. According to the embodiment of the invention, the polypropylene composite material comprises the following components in percentage by mass: 60-70% of polypropylene, 10-30% of polypropylene, 10-30% of polypropylene resin and 10-30% 10%-20% of talcum powder; 5%-10% of an elastomer; 1%-15% of lignin; 0.1%-1% of a stabilizer; 0.01%-0.1% of a beta crystal form nucleating agent; 0%-3% of other auxiliary agents; the stabilizer comprises a hindered phenol main antioxidant, a phosphite auxiliary antioxidant and a hindered amine light stabilizer. The polypropylene composite material provided by the invention is not easy to age and degrade, has a good performance attenuation resisting effect and is long in service life, so that the service life is favorably prolonged, and the safety is favorably improved.

Description

Technical Field

[0001] The present application relates to the technical field of polymer materials, and in particular to polypropylene composite materials, preparation methods thereof, and vehicle parts. Background Art

[0002] Polypropylene is light and cheap, with good mechanical properties, processing properties and heat resistance. It is one of the most widely used and largest varieties of automotive plastics. Since polypropylene molecular chains contain a large number of unstable tertiary carbon atoms, polypropylene materials are subject to heat, oxygen and shear during production, transportation and use, and are easily catalytically oxidized through a series of free radical reactions such as chain initiation, chain transfer and chain termination. As time goes by, the appearance of polypropylene materials will have defects, and the physical and mechanical properties will gradually deteriorate until the original performance is lost (aging degradation). The performance failure of polypropylene materials will seriously affect the safety and service life of the car during driving. Therefore, improving the anti-aging properties of polypropylene is of great significance to ensure the performance of the material and driving safety. Summary of the invention

[0003] The present application aims to solve at least one of the technical problems in the related art to a certain extent. To this end, one purpose of the present application is to provide a polypropylene composite material and a preparation method thereof and a vehicle component. The polypropylene composite material of the present application is not easy to age and degrade, has good resistance to performance degradation, and has a long service life, thereby helping to improve service life and safety.

[0004] The first aspect of the present application provides a polypropylene composite material. According to an embodiment of the present application, the polypropylene composite material, calculated by mass percentage, comprises the following components:

[0005] Polypropylene: 60%-70%;

[0006] Talc: 10% to 20%;

[0007] Elastomer: 5% to 10%;

[0008] Lignin: 1% to 15%;

[0009] Stabilizer: 0.1%~1%;

[0010] β-crystal nucleating agent: 0.01% to 0.1%;

[0011] Other additives: 0%~3%;

[0012] The stabilizers include hindered phenol primary antioxidants, phosphite secondary antioxidants and hindered amine light stabilizers.

[0013] The embodiment of the present application uses a β-crystal nucleating agent, a high-performance stabilizer and lignin in combination, and makes each component satisfy the above-mentioned mass ratio relationship, so as to play an efficient synergistic role, efficiently and continuously stabilize free radicals, delay the aging and degradation process of polypropylene, slow down the attenuation of the mechanical properties of the polypropylene material, and improve the long-term service life of the polypropylene material.

[0014] The second aspect of the present application provides a method for preparing a polypropylene composite material, comprising:

[0015] The raw materials polypropylene, talc, elastomer, lignin, stabilizer, β-crystal nucleating agent and other additives are mixed to obtain a mixed material;

[0016] The mixed material is subjected to melt extrusion, cooling, granulation and drying to obtain a polypropylene composite material;

[0017] Calculated by mass percentage, the raw material composition includes:

[0018] Polypropylene: 60%-70%;

[0019] Talc: 10% to 20%;

[0020] Elastomer: 5% to 10%;

[0021] Lignin: 1% to 15%;

[0022] Stabilizer: 0.1%~1%;

[0023] β-crystal nucleating agent: 0.02% to 0.1%;

[0024] Other additives: 0%~3%;

[0025] The stabilizers include hindered phenol primary antioxidants, phosphite secondary antioxidants and hindered amine light stabilizers.

[0026] The second aspect of the present application provides a vehicle component, comprising the above-mentioned polypropylene composite material, or comprising the polypropylene composite material obtained by the above-mentioned preparation method.

[0027] The polypropylene composite material obtained by the preparation method of the present application can delay the aging and degradation process of polypropylene, slow down the attenuation of the mechanical properties of the polypropylene material, and increase the long-term service life of the polypropylene material.

[0028] The vehicle parts provided in the embodiments of the present application, comprising the above-mentioned polypropylene composite material, have higher safety and longer service life.

[0029] Additional aspects and advantages of the present application will be given in part in the description below, and in part will become apparent from the description below, or will be learned through the practice of the present application. DETAILED DESCRIPTION

[0030] The embodiments of the present application are described in detail below. The embodiments described below are exemplary and are only used to explain the present application, and cannot be understood as limiting the present application.

[0031] It should be noted that the terms "first" and "second" are used for descriptive purposes only and should not be understood as indicating or implying relative importance or implicitly indicating the number of the indicated technical features. Therefore, the features defined as "first" and "second" may explicitly or implicitly include one or more of the features. Further, in the description of this application, unless otherwise specified, the meaning of "plurality" is two or more.

[0032] The endpoints and any values ​​of the ranges disclosed in this application are not limited to the precise ranges or values, and these ranges or values ​​should be understood to include values ​​close to these ranges or values. For numerical ranges, the endpoint values ​​of each range, the endpoint values ​​of each range and the individual point values, and the individual point values ​​can be combined with each other to obtain one or more new numerical ranges, which should be regarded as specifically disclosed in this application.

[0033] In the present application, the terms "comprise" or "include" are open expressions, that is, including the contents specified in the present application but not excluding other contents.

[0034] Since polypropylene molecular chains contain many unstable tertiary carbon atoms, polypropylene materials are easily catalytically oxidized through a series of free radical reactions such as chain initiation, chain transfer and chain termination due to the effects of heat, oxygen and shear during production, transportation and use. As time goes by, polypropylene materials will have defects in appearance, and physical and mechanical properties will gradually deteriorate until they lose their original properties (aging degradation). The performance failure of polypropylene materials will seriously affect the safety and service life of the car during driving.

[0035] The reasons for the aging and degradation of polypropylene are very complex. A large number of studies have shown that the molecular chain structure, aggregate structure, modification and processing aid characteristics, and processing parameters of polypropylene will affect the aging and degradation behavior of polypropylene materials. Based on a deep understanding of the aging and stabilization mechanism of polypropylene, many effective anti-aging measures have been proposed. Among them, in industrial production, the addition of antioxidants can effectively improve the anti-aging properties and performance of polypropylene materials. For example, traditional antioxidants such as 168, 1010, and 1076 are used to improve the anti-aging properties of polypropylene materials. However, traditional antioxidants have poor thermal stability and are easily decomposed in the polypropylene processing temperature window; they have poor compatibility with the polypropylene matrix and are easily migrated and precipitated during use, resulting in poor antioxidant effect of antioxidants on polypropylene, which ultimately causes the performance of polypropylene materials to decay rapidly and poor long-term performance. In addition, other modification additives and fillers have poor compatibility with polypropylene, which will affect its dispersibility in the melt. Since other modification additives and fillers have a certain adsorption effect on antioxidants and light stabilizers, they will further affect the antioxidant effect of antioxidants and light stabilizers, thereby affecting the anti-aging properties of polypropylene.

[0036] To this end, the first aspect of the present application proposes a polypropylene composite material. According to an embodiment of the present application, a polypropylene composite material, calculated by mass percentage, comprises the following components:

[0037] Polypropylene: 60%-70%;

[0038] Talc: 10% to 20%;

[0039] Elastomer: 5% to 10%;

[0040] Lignin: 1% to 15%;

[0041] Stabilizer: 0.1%~1%;

[0042] β-crystal nucleating agent: 0.01% to 0.1%;

[0043] Other additives: 0%~3%;

[0044] The stabilizers include hindered phenol primary antioxidants, phosphite secondary antioxidants and hindered amine light stabilizers.

[0045] In specific examples, the content of lignin is 1%, 2%, 3%, 4%, 5%, 6%, 7%, 8%, 9%, 10%, 11%, 12%, 13%, 14%, 15%, etc. The content of the stabilizer is 0.1%, 0.2%, 0.3%, 0.4%, 0.5%, 0.6%, 0.7%, 0.8%, 0.9%, 1%, etc. The content of the β-crystal nucleating agent is 0.01%, 0.02%, 0.03%, 0.04%, 0.05%, 0.06%, 0.07%, 0.08%, 0.09%, 0.1%, etc.

[0046] In specific examples, the content of polypropylene is 60%, 61%, 62%, 63%, 64%, 65%, 66%, 67%, 68%, 69%, 70%, etc. The content of talc is 10%, 11%, 12%, 13%, 14%, 15%, 16%, 17%, 18%, 19%, 20%; the content of elastomer is 5%, 6%, 7%, 8%, 9%, 10%, etc.

[0047] The embodiment of the present application uses a β-crystal nucleating agent, a high-performance stabilizer and lignin in combination, and makes each component satisfy the above-mentioned mass ratio relationship, so as to play an efficient synergistic role, efficiently and continuously stabilize free radicals, delay the aging and degradation process of polypropylene, slow down the attenuation of the mechanical properties of the polypropylene material, and improve the long-term service life of the polypropylene material.

[0048] The embodiment of the present application can improve the toughness of polypropylene by adding a β-crystal nucleating agent, because 1) the β-crystal nucleating agent has good compatibility with the polypropylene matrix and is evenly distributed in the polypropylene; 2) the addition of the β-crystal nucleating agent greatly increases the relative content of β-crystals and the β-crystals form a network structure of flower-like aggregates, which can absorb impact energy well. On the other hand, the thermal oxidation stability of polypropylene can be improved, because the addition of the β-crystal nucleating agent greatly reduces the crystal size of polypropylene and induces the formation of a large number of β-crystals, thereby 1) reducing the mobility of the molecular chains in the crystalline region and the amorphous region; 2) improving the mechanical coupling between the β-crystal region and the amorphous region; 3) reducing the oxygen diffusion coefficient and solubility coefficient.

[0049] By adding lignin, the embodiment of the present application can improve the strength and stiffness of polypropylene on the one hand, because lignin is used in combination with talcum powder, elastomer, and β-crystal nucleating agent, and the above-mentioned mass percentage conditions are met, and the stiffness and toughness balance of polypropylene composite materials can be achieved. On the other hand, the stability of polypropylene can be further improved, because 1) lignin is evenly distributed in the polypropylene melt; 2) polyphenols in lignin can capture free radicals and prevent the auto-oxidation cycle of polypropylene; 3) the conjugated structure inside the lignin molecule can effectively absorb ultraviolet light, preventing ultraviolet light from directly irradiating the inside of the polypropylene molecular chain to cause photodegradation; 4) lignin is carbonized under high temperature, forming a protective layer on the outer layer of polypropylene, which can reduce the oxygen diffusion rate, thereby improving the antioxidant properties of the polymer.

[0050] In the embodiment of the present application, by adding a stabilizer, the components of the hindered phenol primary antioxidant, the phosphite secondary antioxidant and the hindered amine light stabilizer work synergistically with each other, which can greatly improve the thermal oxidation stability of polypropylene. This is because the selected high-performance heat stabilizer has excellent thermal stability, activity, mobility, processability and excellent compatibility with the polypropylene matrix, and can play a synergistic role during the recycling process and use, and can efficiently and continuously stabilize free radicals (capture free radicals and decompose peroxides) to prevent chain reactions from occurring, thereby delaying the aging and degradation process of polypropylene.

[0051] In a specific example, the content of lignin

[0052] According to the embodiments of the present application, the components are as follows, calculated by mass percentage:

[0053] Polypropylene: 60%-70%;

[0054] Talc: 10% to 20%;

[0055] Elastomer: 5% to 10%;

[0056] Lignin: 5% to 10%;

[0057] Stabilizer: 0.5%~1%;

[0058] β-crystal nucleating agent: 0.03% to 0.05%;

[0059] Other additives: 0.1%~3%.

[0060] The embodiments of the present application further limit the dosage range of the β-crystal nucleating agent, the high-performance stabilizer and the lignin, and the combined use of the β-crystal nucleating agent, the high-performance stabilizer and the lignin can better exert the efficient synergistic effect, delay the aging and degradation process of polypropylene, slow down the attenuation of the mechanical properties of the polypropylene material, and improve the long-term service life of the polypropylene material.

[0061] According to the embodiments of the present application, the mass ratio of the hindered phenol primary antioxidant, the phosphite secondary antioxidant and the hindered amine light stabilizer is 1:(1-6):(1-4).

[0062] In specific examples, the mass ratios of hindered phenol primary antioxidant, phosphite secondary antioxidant and hindered amine light stabilizer are 1:1:1, 1:2:1, 1:3:1, 1:4:1, 1:5:1, 1:6:1, 1:1:2, 1:2:2, 1:3:2, 1:4:2, 1:5:2, 1:6:2, 1:1:3, 1:2:3, 1:3:3, 1:4:3, 1:5:3, 1:6:3, 1:1:4, 1:2:4, 1:3:4, 1:4:4, 1:5:4, 1:6:4 and the like.

[0063] In the embodiments of the present application, the mass ratio of the hindered phenol primary antioxidant, the phosphite secondary antioxidant and the hindered amine light stabilizer meets the above conditions, which is conducive to the hindered phenol primary antioxidant, the phosphite secondary antioxidant and the hindered amine light stabilizer to better exert their synergistic effects and further improve the thermal oxidation stability of polypropylene.

[0064] According to an embodiment of the present application, the mass ratio of the hindered phenol primary antioxidant, the phosphite secondary antioxidant and the hindered amine light stabilizer is 1:4:2.

[0065] In the embodiments of the present application, the mass ratio of the hindered phenol primary antioxidant, the phosphite secondary antioxidant and the hindered amine light stabilizer satisfies 1:4:2, which helps to save costs while improving the thermal oxidation stability of polypropylene.

[0066] According to an embodiment of the present application, the stabilizer satisfies at least one of the following (1) to (3):

[0067] (1 The hindered phenol primary antioxidant includes at least one of tetrakis[β-(3,5-di-tert-butyl-4-hydroxyphenyl) propionate] pentaerythritol ester, 1,3,5-trimethyl-2,4,6-(3,5-di-tert-butyl-4-hydroxybenzyl)benzene and 1,3,5-tris(4-tert-butyl-3-hydroxy-2,6-dimethylbenzyl)-1,3,5-triazine-2,4,6-(1H,3H,5H)-trione;

[0068] (2) the hindered phenol auxiliary antioxidant includes at least one of bis(2,4-di-tert-butylphenyl)pentaerythritol diphosphite and bis(2,4-dicumylphenyl)pentaerythritol-diphosphite;

[0069] (3) The hindered amine light stabilizer includes at least one of poly-{[6-[(1,1,3,3-tetramethylbutyl)-imino]-1,3,5-triazine-2,4-diyl][2-(2,2,6,6-tetramethylpiperidinyl)-amino]-hexylene-[4-(2,2,6,6-tetramethylpiperidinyl)-imino]} and N,N"'-1,2-ethanediylbis[N-[3-[[4,6-di[butyl(1,2,2,6,6-pentamethyl-4-piperidinyl)amino]-1,3,5-triazine-2-yl]amino]propyl]-N,N"-dibutyl-N,N"-bis(1,2,2,6,6-pentamethyl-4-piperidinyl)-1,3,5-triazine-2,4,6-triamine.

[0070] The hindered phenol main antioxidant is used to capture free radicals, the phosphite auxiliary antioxidant is used to decompose hydroperoxides, and the hindered amine light stabilizer inhibits the auto-oxidation cycle of polypropylene. By further limiting the material selection of the above components, it is beneficial to improve the mutual synergistic promotion effect, improve the thermal oxidation stability of polypropylene, and increase the long-term service life of polypropylene materials.

[0071] According to an embodiment of the present application, the lignin includes sulfur-free lignin.

[0072] In the embodiments of the present application, the lignin selected includes sulfur-free lignin, which is beneficial to further reduce the adverse effects on the hindered amine light stabilizer and improve the anti-aging effect of polypropylene.

[0073] According to an embodiment of the present application, the β-crystal nucleating agent includes at least one of the following seven types:

[0074] Condensed ring aromatic compounds;

[0075] Complexes of dicarboxylic acids and oxides of Group IIA metals;

[0076] Complexes of dicarboxylic acids and hydroxides of Group IIA metals;

[0077] A complex of a dicarboxylic acid and a Group IIA metal salt;

[0078] Group IIA metal salts;

[0079] Aromatic amide compounds;

[0080] Rare earth compounds.

[0081] In the embodiments of the present application, the β-crystal nucleating agent includes at least one of the above seven types, which exhibits a good nucleating effect and is beneficial to improving the toughness and thermal oxidation stability of polypropylene.

[0082] Furthermore, in the embodiments of the present application, the β-crystal nucleating agent includes at least one of a Group IIA metal salt and an aromatic amide compound.

[0083] According to an embodiment of the present application, the β-crystal nucleating agent includes at least one of a carboxylic acid metal salt of tetrahydrophthalic anhydride and N,N′-dicyclohexylterephthalamide.

[0084] In the embodiment of the present application, the β-crystal nucleating agent is selected from at least one of the carboxylic acid metal salt of tetrahydrophthalic anhydride and N,N′-dicyclohexylterephthalamide, which exhibits good nucleating effect and compatibility with polypropylene, and is beneficial to improving the toughness and thermal oxidation stability of polypropylene.

[0085] According to an embodiment of the present application, the components of the polypropylene composite material satisfy at least one of the following (1) to (4):

[0086] (1) The polypropylene includes at least one of homopolymer polypropylene, random copolymer polypropylene and impact copolymer polypropylene;

[0087] (2) the elastomer comprises at least one of an ethylene-octene copolymer and an ethylene-butene copolymer;

[0088] (3) The mesh number of talc powder is 1000-5000 mesh, and the silicon dioxide content is not less than 60%;

[0089] (4) Other additives include at least one of lubricants, plasticizers and processing aids.

[0090] In the embodiment of the present application, the polypropylene includes at least one of homopolymer polypropylene, random copolymer polypropylene and impact copolymer polypropylene; homopolymer polypropylene, random copolymer polypropylene and impact copolymer polypropylene have their own mechanical properties, and the polypropylene material with the required mechanical properties can be selected based on the application scenario of the polypropylene composite material. Furthermore, the polypropylene is polypropylene produced by a metallocene catalyst. Compared with the polypropylene prepared by the metallocene catalyst, the polypropylene prepared by the Zieglar-Natta catalyst has a high isotacticity and the isotactic propylene sequence is unevenly distributed on the molecular chain, and the molecular chain stability is worse. It is easier to affect the molecular chain with low isotacticity through the "aging infection" effect, accelerating the oxidative degradation of polypropylene. Therefore, the polypropylene prepared by the metallocene catalyst can be further selected as the matrix resin to improve the anti-aging performance of the composite material.

[0091] In the embodiments of the present application, the elastomer may be selected from ethylene and octene copolymers, or ethylene and butene copolymers, or a combination of the two.

[0092] In the embodiment of the present application, the mesh size of the talc powder meets the above conditions, which is conducive to obtaining better mechanical properties and dispersibility, and saving costs; the silicon dioxide content of the talc powder meets the above requirements, which is conducive to ensuring the purity of the talc powder and reducing the impact of impurities on the anti-aging performance of polypropylene. Further, the mesh size of the talc powder is 2000-3000 mesh.

[0093] In the embodiments of the present application, the mechanical properties of polypropylene are improved through the combined action of polypropylene, elastomer and talcum powder.

[0094] A second aspect of the present application provides a method for preparing a polypropylene composite material, comprising:

[0095] The raw materials polypropylene, talc, elastomer, lignin, stabilizer, β-crystal nucleating agent and other additives are mixed to obtain a mixed material;

[0096] The mixed material is subjected to melt extrusion, cooling, granulation and drying to obtain a polypropylene composite material;

[0097] Calculated by mass percentage, the raw material composition includes:

[0098] Polypropylene: 60%-70%;

[0099] Talc: 10% to 20%;

[0100] Elastomer: 5% to 10%;

[0101] Lignin: 1% to 15%;

[0102] Stabilizer: 0.1%~1%;

[0103] β-crystal nucleating agent: 0.02% to 0.1%;

[0104] Other additives: 0%~3%;

[0105] The stabilizers include hindered phenol primary antioxidants, phosphite secondary antioxidants and hindered amine light stabilizers.

[0106] In specific examples, the content of lignin is 1%, 2%, 3%, 4%, 5%, 6%, 7%, 8%, 9%, 10%, 11%, 12%, 13%, 14%, 15%, etc. The content of the stabilizer is 0.1%, 0.2%, 0.3%, 0.4%, 0.5%, 0.6%, 0.7%, 0.8%, 0.9%, 1%, etc. The content of the β-crystal nucleating agent is 0.01%, 0.02%, 0.03%, 0.04%, 0.05%, 0.06%, 0.07%, 0.08%, 0.09%, 0.1%, etc.

[0107] In specific examples, the content of polypropylene is 60%, 61%, 62%, 63%, 64%, 65%, 66%, 67%, 68%, 69%, 70%, etc. The content of talc is 10%, 11%, 12%, 13%, 14%, 15%, 16%, 17%, 18%, 19%, 20%; the content of elastomer is 5%, 6%, 7%, 8%, 9%, 10%, etc.

[0108] The embodiment of the present application uses a β-crystal nucleating agent, a high-performance stabilizer and lignin in combination, and makes each component satisfy the above-mentioned mass ratio relationship, so as to play an efficient synergistic role, efficiently and continuously stabilize free radicals, delay the aging and degradation process of polypropylene, slow down the attenuation of the mechanical properties of the polypropylene material, and improve the long-term service life of the polypropylene material.

[0109] The embodiment of the present application prepares the polypropylene composite material by melt extrusion molding, which is conducive to industrial production.

[0110] According to an embodiment of the present application, a method for preparing a polypropylene composite material comprises the steps of:

[0111] S1000: polypropylene, talc, elastomer, lignin, stabilizer, β-crystal nucleating agent and other additives are mixed together to obtain a mixed material. In a specific example, the mixing process can be mixed by a high-speed mixer for 6 minutes to 10 minutes until the mixture is uniform.

[0112] S2000: The above-mentioned mixed material is melt-extruded, cooled, granulated, and dried to obtain a polypropylene composite material with resistance to performance degradation. In a specific example, the melt extrusion operation includes: adding the mixed material from the feed port to the twin-screw extruder for melt extrusion, and the processing temperature of each section of the twin-screw extruder is respectively feeding section: 160°C; compression section: 180°C; plasticizing section: 190°C; metering section: 200°C; mixing section: 210°; die head: 210°C; pressure is 12Mpa~18Mpa, main screw speed is 500r / min~600r / min, and the screw combination is selected as weak shear and strong dispersion.

[0113] According to a third aspect of the embodiments of the present application, a vehicle component is provided, comprising the polypropylene composite material described above, or comprising the polypropylene composite material obtained by the above preparation method.

[0114] The vehicle parts provided in the embodiments of the present application, comprising the above-mentioned polypropylene composite material, have higher safety and longer service life.

[0115] According to an embodiment of the present application, vehicle parts include but are not limited to bumpers, instrument panels, door panels and pillar trims, fan blades, fenders, front end modules, engine hood covers, gear box bases, rearview mirror brackets, seat guards, door guards, pillar guards, parcel shelf guards, rear guards, fuel tanks, radiator water chambers, accelerator pedals, truck bumper brackets, etc.

[0116] The scheme of the present application will be explained below in conjunction with the embodiments. It will be appreciated by those skilled in the art that the following embodiments are only used to illustrate the present application and should not be considered as limiting the scope of the present application. If no specific technology or conditions are indicated in the embodiments, the technology or conditions described in the literature in this area or the product specification are carried out. The reagents used or the instruments that do not indicate the manufacturer are all conventional products that can be obtained commercially.

[0117] Example 1

[0118] 12.8 kg of polypropylene-1#, 3 kg of talc, 2 kg of elastomer, 2 kg of lignin, 0.14 kg of high-performance stabilizer (1010:626:944=1:4:2), 0.02 kg of β-crystal nucleating agent NAB82 and 0.04 kg of other additives were added to a high-speed mixer and mixed for 10 minutes until the mixture was uniformly mixed.

[0119] Then, the mixed raw materials are added to the twin-screw extruder from the feeding port for melt extrusion. The processing temperature of each zone of the twin-screw extruder is: zone 1: 160°C, zone 2-5: 180°C, zone 6-9: 200°C, die head: 210°C; pressure 15Mpa, main screw speed 600r / min, and the screw combination is selected as weak shear and strong dispersion. After melt extrusion, cooling, granulation, and drying, the automotive polypropylene composite material 1 with resistance to performance degradation is obtained.

[0120] Example 2-12

[0121] The proportions of talc, elastomer, lignin, high-performance stabilizer, and β-crystal nucleating agent in Example 1 were replaced according to the contents (mass percentage) of each component in Examples 2-12 in Table 1, and all the raw materials were added to a high-speed mixer and mixed for 10 minutes until they were uniformly mixed.

[0122] Then, the raw materials evenly mixed are melt-extruded, cooled, granulated, and dried (the processing technology and process parameters are consistent with those in Example 1) to obtain the automotive polypropylene composite material 2-polypropylene composite material 12 with resistance to performance degradation.

[0123] Embodiment 13

[0124] 12.8 kg of polypropylene-2#, 0.3 kg of talc, 0.2 kg of elastomer, 0.2 kg of lignin, 0.014 kg of high-performance stabilizer (1790:686:944=1:4:2), 0.002 kg of β-crystal nucleating agent NAB82 and 0.004 kg of other additives were added to a high-speed mixer and mixed for 10 minutes until the mixture was uniform.

[0125] Then, the raw materials evenly mixed are melt-extruded, cooled, granulated, and dried (the processing technology and process parameters are consistent with those in Example 1) to obtain a polypropylene composite material 13 for automobiles that is resistant to performance degradation.

[0126] Examples 14-24

[0127] The proportions of talc, elastomer, lignin, high-performance stabilizer, and β-crystal nucleating agent in Example 13 were replaced according to the contents (mass percentage) of the components in Examples 14-24 in Table 1, and all the raw materials were added to a high-speed mixer and mixed for 10 minutes until they were uniformly mixed.

[0128] Then, the raw materials evenly mixed are melt-extruded, cooled, granulated, and dried (the processing technology and process parameters are consistent with those in Example 1) to obtain automotive polypropylene composite materials 14 to polypropylene composite materials 24 that are resistant to performance degradation.

[0129] Embodiment 25

[0130] 12.8 kg of polypropylene-3#, 0.3 kg of talc, 0.2 kg of elastomer, 0.2 kg of lignin, 0.014 kg of high-performance stabilizer (1330:626:119=1:4:2), 0.002 kg of β-crystal nucleating agent NAB82 and 0.004 kg of other additives were added to a high-speed mixer and mixed for 10 minutes until uniformly mixed.

[0131] Then, the raw materials evenly mixed are melt-extruded, cooled, granulated, and dried (the processing technology and process parameters are consistent with those in Example 1) to obtain a polypropylene composite material 13 for automobiles that is resistant to performance degradation.

[0132] Embodiment 26-36

[0133] The proportions of talc, elastomer, lignin, high-performance stabilizer, and β-crystal nucleating agent in Example 25 were replaced according to the contents (mass percentage) of the main components in Examples 14-24 in Table 1, and all the raw materials were added to a high-speed mixer and mixed for 10 minutes until they were uniformly mixed.

[0134] Then, the raw materials evenly mixed are melt-extruded, cooled, granulated, and dried (the processing technology and process parameters are consistent with those in Example 1) to obtain automotive polypropylene composite materials 14 to polypropylene composite materials 24 that are resistant to performance degradation.

[0135] Comparative Examples 1-5

[0136] 12.8 kg of polypropylene-1# was added together with a certain proportion of talcum powder, elastomer, lignin, high-performance stabilizer, β-crystal nucleating agent and other additives (the content of each component (mass percentage) is as shown in Table 2) into a high-speed mixer and mixed for 10 minutes until the mixture is uniform.

[0137] Then, the raw materials evenly mixed were subjected to melt extrusion, cooling, granulation and drying (the processing technology and process parameters were consistent with those in Example 1) to obtain comparative example polypropylene composite materials 1 to polypropylene composite materials 5.

[0138] Comparative Examples 6-10

[0139] 12.8 kg of polypropylene-1# was added together with a certain proportion of talcum powder, elastomer, lignin, high-performance stabilizer, β-crystal nucleating agent and other additives (the content of each component (mass percentage) is as shown in Table 2) into a high-speed mixer and mixed for 10 minutes until the mixture is uniform.

[0140] Then, the raw materials evenly mixed were subjected to melt extrusion, cooling, granulation and drying (the processing technology and process parameters were consistent with those in Example 1) to obtain comparative example polypropylene composite materials 6 to polypropylene composite materials 10.

[0141] Comparative Examples 11-15

[0142] 12.8 kg of polypropylene-1# was added together with a certain proportion of talcum powder, elastomer, lignin, high-performance stabilizer, β-crystal nucleating agent and other additives (the content of each component (mass percentage) is as shown in Table 2) into a high-speed mixer and mixed for 10 minutes until the mixture is uniform.

[0143] Then, the raw materials evenly mixed are subjected to melt extrusion, cooling, granulation and drying treatments (the processing technology and process parameters are consistent with those in Example 1) to obtain comparative example polypropylene composite materials 11 to polypropylene composite materials 15.

[0144] Table 1 Component contents of the examples (mass percentage)

[0145]

[0146] Table 2 Comparative Example Component Content (Mass Percentage)

[0147]

[0148] Note: In each embodiment and comparative example, polypropylene-1# represents homopolymer polypropylene, polypropylene-2# represents random copolymer polypropylene, and polypropylene-3# represents impact copolymer polypropylene; the elastomer is ethylene and octene copolymer; and other additives are lubricant carbon black.

[0149] Performance Testing

[0150] 1. Performance testing methods.

[0151] 1. Melt flow rate (MFR, g / 10min): refer to GB / T 3682.1-2018.

[0152] 2. Mechanical properties, including tensile strength (Mpa), flexural modulus (Mpa), notched impact strength (KJ / m 2 ): Refer to GB / T 1040-92 and GB / T 1043-93; the plastic specimen condition adjustment and test standard environment shall be in accordance with GB / T2918-1998, and shall be carried out under the conditions of (23±2)℃ and relative humidity of (50±5)%, and the specimen condition adjustment time shall be 48h.

[0153] 3. Oven heat aging damage time (h): Refer to ISO 4577-1983 and ASTMD 3079-79, put the polypropylene sample into a 150℃ heat aging test chamber, check the appearance of the sample every hour within 5 hours, check every 8 hours to 16 hours within 360 hours, and check once a day for more than 360 hours, record the time when the sample begins to fail, and take 5 samples to calculate the average value. This standard is used to evaluate the long-term thermal oxidation stability of polypropylene composite materials.

[0154] 4. Failure time of outdoor exposure specimens (d): According to GB / T 3681-83 standard, polypropylene specimens are mounted in a fixture directly connected to the specimen rack. The specimen rack is located on the roof of the building with the exposure surface facing south and at an angle of 23° to the horizontal plane. The appearance changes of the specimens are checked once a week. The specimens are folded 180°. The time of brittle fracture of the specimens that are not in contact with the wood strips is used as the evaluation index. The average value of 5 specimens is taken. This standard is used to evaluate the natural aging performance of polypropylene composite materials.

[0155] 5. Processing performance: Take outdoor exposure specimens from time to time and test the melt flow rate according to GB / T 3682.1-2018 to evaluate the processing performance of polypropylene composites.

[0156] 6. Long-term performance: Take outdoor exposure specimens from time to time and test the mechanical properties according to GB / T 1040-92 and GB / T 1043-93 standards to evaluate the long-term performance of polypropylene composite materials.

[0157] 2. Performance test results

[0158] 1. Melt flow rate test results.

[0159] The test results of the melt flow rate of the polypropylene composite materials provided in the examples and comparative examples are shown in Table 3 and Table 4.

[0160] Table 3 Variation trend of melt flow rate of polypropylene composite materials provided in the examples

[0161]

[0162] Table 4 Variation trend of melt flow rate of polypropylene composite materials provided in comparative examples

[0163]

[0164] Note: In Tables 3 and 4, “ / ” indicates that the melt flow rate is too large to be measured.

[0165] It can be seen from Tables 3 and 4 that at 0 days, the melt flow rate of the test samples of the embodiments is lower than that of the corresponding comparative samples, which indicates that the molecular weight of the test samples of the embodiments is lower and the degree of aging degradation of the polypropylene is smaller. As the exposure time increases, the melt flow rate gradually increases, and the increase in the melt flow rate of the test samples of the embodiments is lower than that of the corresponding comparative samples. When the outdoor exposure time of the embodiments is 60 to 120 days, the melt flow rate is too large to be measured. In contrast, the melt flow rate of the comparative samples is too large to be measured after only 0-30 days of outdoor exposure. It can be seen that adding an appropriate amount of β-crystal nucleating agent, high-performance stabilizer and lignin to the polypropylene material can slow down the reduction of the molecular weight of the polypropylene material and improve the anti-aging performance of the polypropylene material.

[0166] 2. Test results of the failure time of outdoor exposure specimens and the failure time of thermal oven aging specimens

[0167] The test results of the melt flow rate of the polypropylene composite materials provided in the examples and comparative examples are shown in Tables 5 and 6.

[0168] Table 5 Test results of the failure time of the polypropylene composite material heat oven aging specimens and the failure time of the outdoor exposure specimens provided in the examples

[0169]

[0170] Table 6 Test results of the failure time of the polypropylene composite material heat oven aging specimens and the failure time of the outdoor exposure specimens provided in the comparative examples

[0171]

[0172] It can be seen from Table 5 and Table 6 that, compared with Comparative Examples 2-5, the destruction time of the hot oven aging samples of Examples 1-12 increased by 32h to 1104h, and the destruction time of the outdoor exposure sample increased by 5 days to 356 days. Compared with Comparative Examples 7-10, the destruction time of the hot oven aging samples of Examples 13-24 increased by 272h to 1392h, and the destruction time of the outdoor exposure sample increased by 106t days to 420 days. Compared with Comparative Examples 12-15, the destruction time of the hot oven aging samples of Examples 25-36 increased by 872h to 1376h, and the destruction time of the outdoor exposure sample increased by 307 days to 441 days. It can be seen that the embodiments of the present application effectively delay the aging degradation and performance attenuation process of the polypropylene material by compounding and using high-performance stabilizers, β-crystal nucleating agents and lignin.

[0173] 3. Test results of the changing trend of mechanical properties.

[0174] The test results of the melt flow rate of the polypropylene composite materials provided in the examples and comparative examples are shown in Tables 7 and 8.

[0175] Table 7 Change trend of mechanical properties of polypropylene composite materials provided in the examples

[0176]

[0177] Table 8 Mechanical properties trend of comparative polypropylene composites

[0178]

[0179] Note: “ / ” indicates that the mechanical properties of the material cannot be measured.

[0180] From the test results in Table 7, we can see that:

[0181] The initial tensile strength of the anti-performance decay automotive polypropylene material prepared in Example 1-12 is 37.4Mpa-47.2Mpa, the initial flexural modulus is 2640Mpa-3519Mpa, and the initial notched impact strength is 3.4KJ / m 2 ~5.6KJ / m 2 After 360 days of outdoor exposure, the tensile strength attenuation rate was 16.1% to 18.6%, the flexural modulus attenuation rate was 16.1% to 17.3%, and the notched impact strength attenuation rate was 18.0% to 19.0%.

[0182] The initial tensile strength of the anti-performance decay automotive polypropylene material prepared in Examples 13-24 is 28.0Mpa-35.1Mpa, the initial flexural modulus is 1981Mpa-2854Mpa, and the initial notched impact strength is 6.4KJ / m 2 ~9.1KJ / m2 After 360 days of outdoor exposure, the tensile strength attenuation rate was 15.4% to 16.6%, the flexural modulus attenuation rate was 15.4% to 16.6%, and the notched impact strength attenuation rate was 16.9% to 18.0%.

[0183] The initial tensile strength of the anti-performance decay automotive polypropylene material prepared in Examples 25-36 is 24.1Mpa-28.2Mpa, the initial flexural modulus is 992Mpa-2156Mpa, and the initial notched impact strength is 42.3KJ / m 2 ~69.4KJ / m 2 After 360 days of outdoor exposure, the tensile strength attenuation rate was 13.9% to 26.1%, the flexural modulus attenuation rate was 14.0% to 15.4%, and the notched impact strength attenuation rate was 14.9% to 16.4%.

[0184] It can be seen from the test data in Table 7 and Table 8 that the initial tensile strength of the polypropylene material prepared in Comparative Examples 1-5 is 28.3Mpa-41.2Mpa, the initial flexural modulus is 1907Mpa-2804Mpa, and the initial notched impact strength is 2.0KJ / m 2 , ~4.2KJ / m 2 After 360 days of outdoor exposure, the tensile strength attenuation rate of Examples 1-12 of the present application was reduced by 8.69% to 20.91%, the bending modulus attenuation rate was reduced by 9.02% to 22.68%, and the notched impact strength attenuation rate was reduced by 7.67% to 19.1% compared with Comparative Examples 1-5. The initial tensile strength of the polypropylene material prepared in Comparative Examples 6-10 was 19.5Mpa to 30.2Mpa, the initial bending modulus was 1302Mpa to 1963Mpa, and the initial notched impact strength was 3.1KJ / m 2 ~7.3KJ / m 2 After 360 days of outdoor exposure, the tensile strength attenuation rate of Examples 13-24 of the present application was reduced by 9.81% to 20.33%, the bending modulus attenuation rate was reduced by 9.57% to 27.6%, and the notched impact strength attenuation rate was reduced by 8.85% to 20.72% compared with Comparative Examples 6-10. The initial tensile strength of the polypropylene material prepared in Comparative Examples 11-15 was 13.6Mpa to 23.1Mpa, the initial bending modulus was 1001Mpa to 1423Mpa, and the initial notched impact strength was 20.4KJ / m 2 , ~49.2KJ / m 2After 360 days of outdoor exposure, the attenuation rate of tensile strength of Examples 25-36 of the present application was reduced by 1.51% to 17.72% compared with Comparative Examples 11-15, the attenuation rate of flexural modulus was reduced by 12.42% to 29.0%, and the attenuation rate of notched impact strength was reduced by 11.63% to 21.84%. By comparing the examples with the comparative examples, it can be seen that adding β-crystal nucleating agent, high-performance stabilizer and lignin to the polypropylene material can effectively improve the mechanical properties of the polypropylene material, prolong the aging time of the polypropylene material, and reduce the attenuation amplitude of the mechanical properties of the polypropylene, so that the polypropylene material still has certain mechanical properties after 360 days of outdoor exposure.

[0185] In summary, the present invention ensures the rigidity and toughness balance of polypropylene products by compounding metallocene polypropylene resin with talcum powder, lignin, β-crystal nucleating agent and elastomer in a certain proportion; the added β-crystal nucleating agent improves the toughness and thermal oxidation stability of the polypropylene material; the added high-performance stabilizer has excellent thermal stability, activity, mobility, processability and excellent compatibility with the polypropylene matrix, which greatly improves the thermal oxidation stability of polypropylene; the added lignin, β-crystal nucleating agent and high-performance stabilizer can play a highly efficient synergistic role, efficiently and continuously stabilize free radicals, delay the aging and degradation process of polypropylene, slow down the attenuation of mechanical properties of polypropylene materials, and improve the long-term service life of polypropylene materials, thereby successfully preparing a polypropylene composite material for automobiles that is resistant to performance attenuation.

[0186] Although the embodiments of the present application have been shown and described above, it can be understood that the above embodiments are exemplary and cannot be understood as limitations on the present application. Ordinary technicians in this field can change, modify, replace and modify the above embodiments within the scope of the present application.

Claims

1. A polypropylene composite material, characterized in that: Calculated by mass percentage, it contains the following components: Polypropylene: 60%-70%; Talc: 10% to 20%; Elastomer: 5% to 10%; Lignin: 1% to 15%; Stabilizer: 0.1%~1%; β-crystal nucleating agent: 0.02% to 0.1%; Other additives: 0%~3%; The stabilizer comprises a hindered phenol primary antioxidant, a phosphite secondary antioxidant and a hindered amine light stabilizer.

2. The polypropylene composite material according to claim 1, characterized in that: Calculated by mass percentage, it contains the following components: Polypropylene: 60%-70%; Talc: 10% to 20%; Elastomer: 5% to 10%; Lignin: 5% to 10%; Stabilizer: 0.5%~1%; β-crystal nucleating agent: 0.03% to 0.05%; Other additives: 0.1%~3%.

3. The polypropylene composite material according to claim 1 or 2, characterized in that: The mass ratio of the hindered phenol primary antioxidant, the phosphite secondary antioxidant and the hindered amine light stabilizer is 1:(1-6):(1-4).

4. The polypropylene composite material according to claim 3, characterized in that: The mass ratio of the hindered phenol primary antioxidant, the phosphite secondary antioxidant and the hindered amine light stabilizer is 1:4:

2.

5. The polypropylene composite material according to any one of claims 1 to 4, characterized in that: The stabilizer satisfies at least one of the following (1) to (3): (1) The hindered phenol primary antioxidant comprises at least one of tetrakis[β-(3,5-di-tert-butyl-4-hydroxyphenyl) propionate] pentaerythritol ester, 1,3,5-trimethyl-2,4,6-(3,5-di-tert-butyl-4-hydroxybenzyl)benzene and 1,3,5-tris(4-tert-butyl-3-hydroxy-2,6-dimethylbenzyl)-1,3,5-triazine-2,4,6-(1H,3H,5H)-trione; (2) the hindered phenol auxiliary antioxidant comprises at least one of bis(2,4-di-tert-butylphenyl)pentaerythritol diphosphite and bis(2,4-dicumylphenyl)pentaerythritol-diphosphite; (3) The hindered amine light stabilizer includes at least one of poly-{[6-[(1,1,3,3-tetramethylbutyl)-imino]-1,3,5-triazine-2,4-diyl][2-(2,2,6,6-tetramethylpiperidinyl)-amino]-hexylene-[4-(2,2,6,6-tetramethylpiperidinyl)-imino]} and N,N"'-1,2-ethanediylbis[N-[3-[[4,6-di[butyl(1,2,2,6,6-pentamethyl-4-piperidinyl)amino]-1,3,5-triazine-2-yl]amino]propyl]-N,N"-dibutyl-N,N"-bis(1,2,2,6,6-pentamethyl-4-piperidinyl)-1,3,5-triazine-2,4,6-triamine.

6. The polypropylene composite material according to any one of claims 1 to 5, characterized in that: The lignin includes sulfur-free lignin.

7. The polypropylene composite material according to any one of claims 1 to 6, characterized in that: The β-crystal nucleating agent includes at least one of the following seven types: Condensed ring aromatic compounds; Complexes of dicarboxylic acids and oxides of Group IIA metals; Complexes of dicarboxylic acids and hydroxides of Group IIA metals; A complex of a dicarboxylic acid and a Group IIA metal salt; Group IIA metal salts; Aromatic amide compounds; Rare earth compounds.

8. The polypropylene composite material according to any one of claims 1 to 7, characterized in that: The β-crystal nucleating agent includes at least one of a carboxylic acid metal salt of tetrahydrophthalic anhydride and N,N′-dicyclohexylterephthalamide.

9. The polypropylene composite material according to any one of claims 1 to 8, characterized in that: The component satisfies at least one of the following (1) to (4): (1) The polypropylene comprises at least one of homopolymer polypropylene, random copolymer polypropylene and impact copolymer polypropylene; (2) The elastomer comprises at least one of ethylene-octene copolymer and ethylene-butene copolymer; (3) The talc powder has a mesh size of 1000 to 5000 mesh and a silicon dioxide content of not less than 60%; (4) The other additives include at least one of a lubricant, a plasticizer and a processing aid.

10. A method for preparing a polypropylene composite material, characterized in that: include: The raw materials polypropylene, talc, elastomer, lignin, stabilizer, β-crystal nucleating agent and other additives are mixed to obtain a mixed material; The mixed material is subjected to melt extrusion, cooling, granulation and drying to obtain a polypropylene composite material; Calculated by mass percentage, the raw material composition includes: Polypropylene: 60%-70%; Talc: 10% to 20%; Elastomer: 5% to 10%; Lignin: 1% to 15%; Stabilizer: 0.1%~1%; β-crystal nucleating agent: 0.02% to 0.1%; Other additives: 0%~3%; The stabilizers include hindered phenol primary antioxidants, phosphite secondary antioxidants and hindered amine light stabilizers.

11. A vehicle component, characterized in that: A polypropylene composite material comprising any one of claims 1 to 9, or a polypropylene composite material obtained by the preparation method according to claim 10.

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