Composite photocatalyst, polypropylene material and preparation method thereof and automotive interior part

Abstract

The application provides a composite photocatalyst, a polypropylene material and a preparation method thereof and an automobile interior part, and the composite photocatalyst comprises a molecular sieve loaded silver halide / bismuth oxyhalide and an activated carbon fiber loaded transition metal oxide. The molecular sieve loaded silver halide / bismuth oxyhalide can form a nano structure with high catalytic activity, and can effectively decompose VOC such as benzene series in the polypropylene material under ultraviolet light irradiation; and the activated carbon fiber loaded transition metal oxide can chemically react with aldehyde VOC, and effectively decomposes VOC such as aldehyde in the polypropylene material. By compounding the polypropylene resin, the stabilizer, the composite photocatalyst and the acid absorbent, the polypropylene material prepared from the polypropylene material has low odor and VOC content.

Description

Technical Field

[0001] This application relates to the field of polypropylene materials, and more particularly to a composite photocatalyst, polypropylene materials and their preparation methods, and automotive interior parts. Background Technology

[0002] Currently, polypropylene accounts for approximately 50% of the total plastics used in automobiles. However, polypropylene undergoes severe aging and degradation during processing and use, producing large amounts of odorous VOCs. In recent years, to improve in-vehicle air pollution, major automakers have increased their R&D investment in polypropylene material emissions control to meet the performance requirements for automotive plastics.

[0003] However, due to the differences in chemical properties and volatilization rates among different VOCs, it is difficult to achieve the desired adsorption effect using only physical adsorption in practical applications. Summary of the Invention

[0004] To address the aforementioned issues, this application aims to introduce a composite photocatalyst, a polypropylene material, a method for preparing the same, and automotive interior parts, with the goal of improving the technical problem of maintaining the low odor and low VOC content of polypropylene materials.

[0005] To achieve the above objectives, in a first aspect, embodiments of this application provide a composite photocatalyst, the composite photocatalyst comprising the following components:

[0006] Molecular sieve-supported silver halide / bismuth halide; and

[0007] Activated carbon fibers loaded with transition metal oxides.

[0008] Optionally, in some embodiments of this application, the mass ratio of the molecular sieve-loaded silver halide / bismuth halide to the activated carbon fiber-loaded transition metal oxide ranges from 0.5 to 2.

[0009] Optionally, in some embodiments of this application, the molecular sieve includes at least one of ZSM-5 type molecular sieve, type A molecular sieve, type X molecular sieve, type Y molecular sieve, mesoporous molecular sieve, and hydrophobic molecular sieve;

[0010] Preferably, the molecular sieve includes ZSM-5 type molecular sieve or hydrophobic molecular sieve.

[0011] Optionally, in some embodiments of this application, the silver halide includes at least one of silver chloride, silver bromide, and silver iodide; and / or

[0012] The bismuth oxyhalide includes at least one of bismuth oxychloride, bismuth oxybromide, and bismuth oxyiodide.

[0013] Optionally, in some embodiments of this application, the transition metal oxide includes at least one of manganese oxide, chromium oxide, cobalt oxide, zinc oxide, vanadium oxide, and zirconium oxide;

[0014] Preferably, the transition metal oxide includes manganese oxide or chromium oxide.

[0015] Optionally, in some embodiments of this application, the diameter of the activated carbon fiber is 5 μm to 10 μm; and / or

[0016] The specific surface area of ​​the activated carbon fiber is 1800 m². 2 / g to 2200m 2 / g; and / or

[0017] The activated carbon fiber has a pore size of 1 nm to 2 nm.

[0018] Secondly, embodiments of this application provide a method for preparing a composite photocatalyst, wherein the molecular sieve-supported silver halide / bismuth halide is prepared by the following steps:

[0019] The bismuth salt is dissolved in the first solvent and stirred to obtain a bismuth salt solution;

[0020] Silver salt and potassium halide were dissolved separately in a second solvent and stirred to obtain silver salt solution and potassium halide solution;

[0021] The silver salt solution was added to the bismuth salt solution and stirred to obtain the first mixture;

[0022] Then, potassium halide solution is added to the first mixture, and the mixture is heated and stirred to obtain the second mixture.

[0023] Then add molecular sieves to the second mixture and continue stirring to obtain the first mixture;

[0024] The first mixture was cooled, dried, and calcined to obtain molecular sieve-supported silver halide / bismuth halide.

[0025] Secondly, embodiments of this application provide a method for preparing a composite photocatalyst, wherein the activated carbon fiber-supported transition metal oxide is prepared by the following steps:

[0026] Activated carbon fibers were added to a transition metal salt solution and stirred to obtain a second mixture;

[0027] The second mixture was dried and calcined to obtain activated carbon fibers loaded with transition metal oxides.

[0028] Thirdly, embodiments of this application provide a polypropylene material, the polypropylene material comprising the following components in parts by weight:

[0029] 70 to 80 parts of polypropylene resin;

[0030] 0.5 to 2 parts of molecular sieve-supported photocatalyst;

[0031] 0.5 to 2 parts of activated carbon fiber supported photocatalyst.

[0032] Optionally, in some embodiments of this application, the molecular sieve-supported photocatalyst comprises molecular sieve-supported silver halide / bismuth halide; and / or

[0033] The activated carbon fiber supported photocatalyst comprises activated carbon fiber supported transition metal oxides;

[0034] Preferably, the mass ratio of the molecular sieve-supported silver halide / bismuth halide to the activated carbon fiber-supported transition metal oxide ranges from 0.5 to 2.

[0035] Optionally, in some embodiments of this application, the molecular sieve includes at least one of ZSM-5 type molecular sieve, type A molecular sieve, type X molecular sieve, type Y molecular sieve, mesoporous molecular sieve, and hydrophobic molecular sieve;

[0036] Preferably, the molecular sieve includes ZSM-5 type molecular sieve or hydrophobic molecular sieve.

[0037] Optionally, in some embodiments of this application, the silver halide includes at least one of silver chloride, silver bromide, and silver iodide; and / or

[0038] The bismuth oxyhalide includes at least one of bismuth oxychloride, bismuth oxybromide, and bismuth oxyiodide.

[0039] Optionally, in some embodiments of this application, the transition metal oxide includes at least one of manganese oxide, chromium oxide, cobalt oxide, zinc oxide, vanadium oxide, and zirconium oxide;

[0040] Preferably, the transition metal oxide includes manganese oxide or chromium oxide.

[0041] Optionally, in some embodiments of this application, the diameter of the activated carbon fiber is 5 μm to 10 μm; and / or

[0042] The specific surface area of ​​the activated carbon fiber is 1800 m². 2 / g to 2200m 2 / g; and / or

[0043] The activated carbon fiber has a pore size of 1 nm to 2 nm.

[0044] Optionally, in some embodiments of this application, the polypropylene resin is prepared using a hydrogenation method and a spherizone / spheripol process; and / or

[0045] The weight-average molecular weight of the polypropylene resin ranges from 200,000 to 350,000.

[0046] Optionally, in some embodiments of this application, 15 to 25 parts of filler are also included; the filler includes at least one of talc, light calcium carbonate, and silica;

[0047] Preferably, the average particle size of the filler is in the range of 2000 mesh to 3000 mesh.

[0048] Optionally, in some embodiments of this application, 0.1 to 0.5 parts of a stabilizer are also included; the stabilizer includes hindered phenolic antioxidant, phosphite antioxidant and hindered amine light stabilizer; preferably, the mass ratio of the hindered phenolic antioxidant, phosphite antioxidant and hindered amine light stabilizer is in the range of 1:(1-4):1.

[0049] Optionally, in some embodiments of this application, the hindered phenolic antioxidant includes at least one of pentaerythritol tetrakis[β-(3,5-di-tert-butyl-4-hydroxyphenyl)propionate], 1,3,5-trimethyl-2,4,6-(3,5-di-tert-butyl-4-hydroxyphenylmethyl)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.

[0050] Optionally, in some embodiments of this application, the phosphite antioxidant includes at least one of tris[2,4-di-tert-butylphenyl] phosphite, bis(2,4-di-tert-butylphenyl) pentaerythritol diphosphite, and bis(2,4-dicumylphenyl) pentaerythritol-diphosphite.

[0051] Optionally, in some embodiments of this application, 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]}, N,N”'-1,2-ethylenedimethyldi[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”-di(1,2,2,6,6-pentamethyl-4-piperidinyl)-1,3,5-triazine-2,4,6-triamine].

[0052] Optionally, in some embodiments of this application, 0.1 to 1 part of an acid absorbent is also included; the acid absorbent includes at least one of metal oxides, lactates, benzoates, silicates, stearates, and hydrotalcites.

[0053] Optionally, in some embodiments of this application, 0.1 to 3 parts of an additive are also included; the additive includes at least one of carbon black and lubricant.

[0054] Fourthly, embodiments of this application provide a method for preparing a polypropylene material, the method comprising the following steps:

[0055] Polypropylene resin, filler, stabilizer, molecular sieve supported photocatalyst, activated carbon fiber supported photocatalyst, acid absorber and additives are mixed and then melt-extruded and granulated to obtain polypropylene material.

[0056] Optionally, in some embodiments of this application, the melt extrusion temperature is 160°C to 210°C; and / or

[0057] The pressure of the melt extrusion is 12 MPa to 18 MPa.

[0058] Fifthly, embodiments of this application provide an automotive interior component, the automotive interior component comprising the aforementioned polypropylene material.

[0059] Optionally, in some embodiments of this application, the automotive interior components include at least one of a dashboard, instrument panel, door panel, pillar trim, and seat back panel.

[0060] The composite photocatalyst of this application consists of silver halide / bismuth halide supported on molecular sieves and transition metal oxides supported on activated carbon fibers. Silver halide / bismuth halide possesses a highly catalytically active nanostructure, capable of effectively decomposing benzene compounds under ultraviolet light irradiation. The electrostatic effect and pore structure of the molecular sieve facilitate the diffusion and migration of photogenerated electrons and intermediates, accelerating the photocatalytic reaction of benzene compounds. Therefore, silver halide / bismuth halide supported on molecular sieves exhibits excellent catalytic activity for benzene-based VOCs. Activated carbon fibers possess a large specific surface area and abundant porous structure, effectively capturing VOCs. Furthermore, the surface of activated carbon fibers contains oxygen-containing functional groups such as carbonyl, hydroxyl, and carboxyl groups, which can chemically react with aldehyde compounds. In addition, transition metal oxides can act as active centers, participating in the redox process in the photocatalytic reaction and promoting the degradation of aldehyde pollutants. Therefore, transition metal oxides supported on activated carbon fibers exhibit excellent catalytic activity for aldehyde-based VOCs.

[0061] The polypropylene material in this application embodiment is based on polypropylene resin, with the addition of molecular sieve supported photocatalyst, activated carbon fiber supported photocatalyst and acid absorber, which achieves low odor and VOC content in the polypropylene material, and makes the prepared polypropylene composite material have ultra-low odor and ultra-low VOC content. Detailed Implementation

[0062] The technical solutions in the embodiments of this application will be clearly and completely described below with reference to the embodiments of this application. Obviously, the described embodiments are only some embodiments of this application, and not all embodiments. Based on the embodiments of this application, all other embodiments obtained by those skilled in the art without creative effort are within the protection scope of this application.

[0063] Polypropylene (PP) is inexpensive, low-density, and possesses good mechanical properties, heat resistance, and electrical insulation, making it the most widely used thermoplastic in the automotive industry. Data shows that PP accounts for approximately 50% of the total plastics used in a vehicle, and over 70 types of automotive interior components utilize PP materials. However, the pungent odor and volatile organic compounds (VOCs) emitted by PP significantly reduce its widespread applicability in automotive interiors.

[0064] In recent years, to improve in-vehicle air pollution, domestic and foreign automakers have continuously increased their R&D investment in the emission performance of materials, tracing the sources of pollutants and implementing targeted control and elimination measures. Research has found that VOCs and odors from automotive PP materials originate from a wide range of sources. These include residual monomers and oligomers, solvents and catalysts during the polymerization process, degradation of PP during modification, storage, and transportation due to light, heat, oxygen, and shear, and the thermal decomposition of processing aids, all of which contribute to abnormal material odors.

[0065] Many researchers have focused on both internal factors (PP resin characteristics) and external factors (modifying agent characteristics and process parameters) to study how to slow down the aging and degradation process of PP, thereby improving the stability of PP and ultimately effectively reducing the VOC and odor of PP materials.

[0066] CN 101691435A describes a low-VOC PP composite material for automotive interior parts prepared using a hydrogen-modified polypropylene method, avoiding the organic peroxide VOCs and irritating odors produced by the molecular chain breakage of polypropylene produced by conventional degradation methods. CN103788471A describes a compound of fully vulcanized powdered silicone rubber, zeolite powder, and boehmite to effectively improve the adsorption efficiency of zeolite powder and boehmite, significantly reducing the VOC release content in polypropylene; moreover, the fully vulcanized powdered silicone rubber itself, nano-dispersed in polypropylene resin, can also adsorb residual VOCs in polypropylene to a certain extent, delaying their release. However, the introduction of fully vulcanized powdered silicone rubber is not conducive to reducing the material's odor and also affects the material's mechanical properties. CN101570612A describes the decomposition of aldehyde small organic molecules through the photocatalytic effect of zinc salt-doped nano-TiO2 particles under visible light, but it cannot effectively reduce benzene VOCs. CN102875895A introduces a VOC stripping agent into the polypropylene melt and removes VOCs through vacuum extraction, but the effect on reducing the material's odor is not significant. CN 111363198A reduces the content of small molecule alkane generated during the preparation of polypropylene composites by adding light shale. However, light shale has limited adsorption capacity for oxygen-containing VOCs with strong odors.

[0067] In summary, polypropylene undergoes severe aging and degradation during processing, generating large amounts of odorous VOCs. Furthermore, residual impurities in the raw materials and the decomposition of additives also contribute to the poor VOC emission performance of polypropylene. Some patents employ the addition of adsorbents to reduce VOC release; however, different VOCs have varying chemical properties and volatilization rates, and adsorbents have limited selectivity and adsorption capacity, making it difficult to achieve ideal adsorption effects in practical applications.

[0068] In view of this, embodiments of this application provide a composite photocatalyst, a polypropylene material, a method for preparing the same, and an automotive interior component.

[0069] In a first aspect, embodiments of this application provide a composite photocatalyst, which comprises the following components:

[0070] Molecular sieve-supported silver halide / bismuth halide; and

[0071] Activated carbon fibers loaded with transition metal oxides.

[0072] By adopting the above scheme, molecular sieves loaded with silver halide / bismuth halide can form nanostructures with high catalytic activity, which can effectively decompose VOCs such as benzene series compounds in polypropylene materials under ultraviolet light irradiation; activated carbon fibers loaded with transition metal oxides can chemically react with aldehyde VOCs, effectively decomposing aldehydes and other VOCs in polypropylene materials. This composite photocatalyst can achieve ideal adsorption effect in practical applications.

[0073] It should be further explained that the reaction principle of molecular sieve-supported silver halide / bismuth halide is as follows:

[0074] Molecular sieves are porous materials that can selectively adsorb VOCs such as benzene compounds onto their surface or within their pores through intermolecular interactions. Loading silver halide / bismuth halide onto molecular sieves facilitates the formation of highly catalytically active nanostructures, enabling the effective decomposition of VOCs such as benzene compounds under ultraviolet light irradiation. Furthermore, the electrostatic effects and pore structure of molecular sieves promote the diffusion and migration of photogenerated electrons and intermediate products, accelerating the photodegradation reaction of benzene compounds.

[0075] It should be further explained that the reaction principle of activated carbon fiber loaded with transition metal oxides is as follows:

[0076] Activated carbon fibers loaded with transition metal oxides can effectively reduce the pungent odor and VOCs such as aldehydes in polypropylene materials. Activated carbon fibers possess a large specific surface area and abundant porous structure, enabling them to effectively capture and adsorb low concentrations of VOCs. Furthermore, the surface of activated carbon fibers contains oxygen-containing functional groups such as carbonyl hydroxyl and carboxyl groups, enhancing their reactivity with aldehyde VOCs. This leads to a chemical reaction, achieving stable adsorption of aldehyde VOCs. In addition, the transition metal oxides can act as active centers, participating in the redox process in photocatalytic reactions and promoting the degradation of aldehyde VOCs.

[0077] It is understandable that this composite photocatalyst can be used not only as a photocatalyst, but also as an adsorbent, deodorizer, etc.

[0078] In some embodiments of this application, the mass ratio of molecular sieve-supported silver halide / bismuth halide to activated carbon fiber-supported transition metal oxide can range from 0.5 to 2. Further, the mass ratio of molecular sieve-supported silver halide / bismuth halide to activated carbon fiber-supported transition metal oxide can be 0.5, 0.8, 1, 1.2, 1.5, 1.8, 2, or any value between two adjacent values ​​mentioned above.

[0079] In some embodiments of this application, the molecular sieve may include at least one of ZSM-5 type molecular sieve, type A molecular sieve, type X molecular sieve, type Y molecular sieve, mesoporous molecular sieve, and hydrophobic molecular sieve. Further, the molecular sieve may include ZSM-5 type molecular sieve or hydrophobic molecular sieve.

[0080] It should be noted that the ZSM-5 molecular sieve has a structurally stable five-membered ring and a high silicon-to-aluminum ratio in its framework, which enables the ZSM-5 molecular sieve to exhibit great selectivity, as well as excellent thermal stability and hydrophobicity.

[0081] Type A molecular sieves have regular pore structures, uniform pore sizes, strong adsorption selectivity, and can withstand high temperatures and chemical reaction environments.

[0082] X-type and Y-type molecular sieves have large pore sizes, enabling them to efficiently adsorb a variety of gas and liquid molecules, and are widely applicable for adsorbing larger molecules. Moreover, Y-type molecular sieves maintain structural stability even at high temperatures.

[0083] Mesoporous molecular sieves have large pore sizes and specific surface areas, making them suitable for diffusion and mass transfer of macromolecular reactants.

[0084] Hydrophobic molecular sieves have excellent hydrophobicity and high porosity, and can maintain good adsorption performance even in high humidity environments. They can selectively adsorb VOCs even in water-containing environments.

[0085] In some embodiments of this application, silver halide may include at least one of silver chloride, silver bromide, and silver iodide.

[0086] By adopting the above scheme, silver chloride, silver bromide, and silver iodide can generate photogenerated electrons and holes under light conditions, and have certain photocatalytic activity. They can be used in catalytic processes such as selective oxidation reactions to achieve the degradation of VOCs.

[0087] In some embodiments of this application, bismuth oxyhalide may include at least one of bismuth oxychloride, bismuth oxybromide, and bismuth oxyiodide.

[0088] By adopting the above scheme, bismuth oxyhalide can be bismuth oxychloride, bismuth oxybromine, or bismuth oxyiodide. Chlorine, bromine, and iodine are all common halogen elements. The bismuth-oxygen layer sandwiched between two layers of halogen atoms can form a self-built electric field, which accelerates the transport of charge carriers from the inside to the surface, thereby improving the separation efficiency of photogenerated charge carriers. This structure makes bismuth oxyhalide exhibit significant activity in the field of photocatalysis.

[0089] In some embodiments of this application, the transition metal oxide may include at least one selected from manganese oxide, chromium oxide, cobalt oxide, zinc oxide, vanadium oxide, and zirconium oxide. Further, the transition metal oxide may include manganese oxide or chromium oxide.

[0090] By adopting the above scheme, manganese oxide, chromium oxide, cobalt oxide, cerium oxide, vanadium oxide, or zirconium oxide can all serve as active centers to absorb photon energy, excite electron transitions, and generate photogenerated electron-hole pairs. These photogenerated charge carriers can participate in redox reactions and promote the degradation of aldehyde VOCs.

[0091] In some embodiments of this application, the diameter of the activated carbon fiber can be from 5 μm to 10 μm.

[0092] By adopting the above scheme, the activated carbon fibers in the above diameter range have a larger loading area, thereby improving the adsorption capacity of activated carbon fibers for irritating odors and VOCs; at the same time, the activated carbon fibers can be loaded with more silver halides and bismuth halides, which helps to improve the photocatalytic effect on VOCs.

[0093] In some embodiments of this application, the specific surface area of ​​activated carbon fibers can be 1800 m². 2 / g to 2200m 2 / g.

[0094] By employing the above-described scheme, this application defines a larger specific surface area of ​​activated carbon fibers, enabling effective capture and adsorption of low concentrations of VOCs. Furthermore, due to the larger specific surface area of ​​the activated carbon fibers, more oxygen-containing functional groups such as carbonyl, hydroxyl, or carboxyl groups are attached to their surface, enhancing the reactivity of the activated carbon fibers with aldehyde VOCs. This leads to a chemical reaction between the two, achieving stable adsorption of aldehyde VOCs.

[0095] In some embodiments of this application, the pore size of the activated carbon fiber can be from 1 nm to 2 nm.

[0096] By adopting the above method, the pore size of the activated carbon fiber is limited to a small size, enabling it to efficiently adsorb low concentrations of VOCs.

[0097] Secondly, embodiments of this application provide a method for preparing a composite photocatalyst, wherein the molecular sieve-supported silver halide / bismuth halide oxide is prepared by the following steps:

[0098] S10. Dissolve the bismuth salt in the first solvent and stir to obtain a bismuth salt solution;

[0099] S11. Dissolve the silver salt and potassium halide separately in the second solvent and stir to obtain the silver salt solution and potassium halide solution;

[0100] S12. Add the silver salt solution to the bismuth salt solution and stir to obtain the first mixture;

[0101] S13. Then add potassium halide solution to the first mixture, heat and stir to obtain the second mixture;

[0102] S14. Add molecular sieve to the second mixture and continue stirring to obtain the first mixture;

[0103] S15. The first mixture is cooled, dried, and calcined to obtain molecular sieve-supported silver halide / bismuth halide.

[0104] In some embodiments of this application, in step S10, the bismuth salt can be bismuth nitrate pentahydrate. The first solvent can be ethylene glycol.

[0105] In some embodiments of this application, in step S11, the silver salt can be silver nitrate. The second solvent can be deionized water. The potassium halide can be any one of potassium chloride, potassium bromide, and potassium iodide.

[0106] In some embodiments of this application, in step S11, stirring can be performed by heating. The temperature for heating and stirring can be between 85°C and 95°C. Exemplarily, the temperature for heating and stirring can be 85°C, 86°C, 87°C, 88°C, 89°C, 90°C, 91°C, 92°C, 93°C, 94°C, 95°C, or any value between two adjacent values ​​mentioned above.

[0107] In some embodiments of this application, the stirring time in step S11 can be from 1.5h to 2.5h. Exemplarily, the stirring time can be 1.5h, 1.6h, 1.7h, 1.8h, 1.9h, 2h, 2.1h, 2.2h, 2.3h, 2.4h, 2.5h, or any value between two adjacent values ​​mentioned above.

[0108] In some embodiments of this application, in step S14, the first mixture contains precipitate.

[0109] In some embodiments of this application, in step S15, cooling can cool the third solution to room temperature, which can be 25±5°C.

[0110] In some embodiments of this application, in step S15, drying can be performed in an oven at 75°C to 85°C for 10 to 14 hours. Exemplarily, drying can be performed in an oven at 80°C for 12 hours; drying can be performed by heating at 75°C for 14 hours; or drying can be performed in an oven at 85°C for 10 hours.

[0111] Secondly, embodiments of this application also provide a method for preparing a composite photocatalyst, wherein the transition metal oxide supported on activated carbon fibers is prepared by the following steps:

[0112] S20. Add activated carbon fiber to a transition metal salt solution and stir to obtain a second mixture;

[0113] S21. The second mixture is dried and calcined to obtain activated carbon fiber loaded with transition metal oxide.

[0114] In some embodiments of this application, in step S21, drying can be performed in an oven at 90°C to 110°C for 10 to 14 hours. Exemplarily, drying can be performed in an oven at 100°C for 12 hours.

[0115] In some embodiments of this application, in step S21, calcination can be carried out in a muffle furnace, rotary kiln, calcining furnace, or tubular furnace.

[0116] In some embodiments of this application, in step S21, calcination can be performed at a temperature of 450°C to 550°C for 4 to 8 hours. Exemplarily, calcination can be performed at 450°C for 8 hours; calcination can be performed at 500°C for 6 hours; or calcination can be performed at 550°C for 4 hours.

[0117] Thirdly, embodiments of this application provide a polypropylene material, which comprises the following components in parts by weight:

[0118] 70 to 80 parts of polypropylene resin;

[0119] 0.5 to 2 parts of molecular sieve-supported photocatalyst;

[0120] 0.5 to 2 parts of activated carbon fiber supported photocatalyst.

[0121] By adopting the above-mentioned scheme, this application uses polypropylene resin as the main body and adds a molecular sieve-supported photocatalyst to effectively reduce the odor and VOCs such as benzene compounds in the polypropylene material; adding an activated carbon fiber-supported photocatalyst can effectively reduce the odor and VOCs such as aldehydes in the polypropylene material. In summary, the polypropylene material of this application embodiment achieves low odor and low VOC content, and the prepared polypropylene material has ultra-low odor and ultra-low VOC content. In addition, the molecular sieve-supported photocatalyst and the activated carbon fiber-supported photocatalyst have minimal impact on the mechanical properties of the prepared polypropylene material, which is beneficial to ensuring that the prepared polypropylene material has both low odor, low VOC content and good mechanical properties.

[0122] In some embodiments of this application, the molecular sieve-supported photocatalyst includes molecular sieve-supported silver halide / bismuth halide. The selection range of molecular sieve-supported silver halide / bismuth halide is the same as that provided in the first aspect above.

[0123] In some embodiments of this application, the activated carbon fiber supported photocatalyst may include activated carbon fiber supported transition metal oxides. The selection range of activated carbon fiber supported transition metal oxides is the same as that provided in the first aspect above.

[0124] In some embodiments of this application, the range of the mass ratio of molecular sieve-supported silver halide / bismuth halide to activated carbon fiber-supported transition metal oxide is the same as the range of the mass ratio of molecular sieve-supported silver halide / bismuth halide to activated carbon fiber-supported transition metal oxide in the aforementioned first aspect composite photocatalyst.

[0125] In some embodiments of this application, the selection range of molecular sieves is the same as that of the molecular sieves in the first aspect described above.

[0126] In some embodiments of this application, the selection range of silver halide is the same as that of the silver halide selection range in the first aspect described above. The selection range of bismuth halide is the same as that of bismuth halide selection range in the first aspect described above.

[0127] In some embodiments of this application, the range of transition metal oxides selected is the same as that selected in the first aspect.

[0128] In some embodiments of this application, the parameters of the activated carbon fiber are defined. For example, the diameter, specific surface area, and pore size of the activated carbon fiber can all be the same as the parameters of the activated carbon fiber described in the first aspect.

[0129] In some embodiments of this application, the polypropylene resin can be prepared using a hydrogen conditioning method and a Spherizone / Spheripol process.

[0130] By employing the above scheme, the polypropylene produced by adjusting the molecular weight through hydrogenation achieves high fluidity by introducing hydrogen gas during polymerization, resulting in a lower odor level in the synthesized polypropylene. The Spherizone / Spheripol process includes a steam drying process, where the blown steam accelerates VOC release at high temperatures, thus resulting in a lower VOC content in the synthesized polypropylene resin.

[0131] It should be noted that Spherizone is a gas-phase polypropylene production process that employs a unique multi-zone circulating reactor (MZCR) technology. Spheripol, on the other hand, is a mature polypropylene production process that combines the technologies of a liquid-phase loop reactor and a gas-phase fluidized bed reactor.

[0132] In some embodiments of this application, the weight-average molecular weight of the polypropylene resin can range from 200,000 to 350,000.

[0133] By adopting the above-mentioned scheme, this application limits the weight-average molecular weight of polypropylene resin to between 200,000 and 350,000, which helps to balance the processing performance of polypropylene resin in subsequent modification processes and the mechanical properties of the prepared polypropylene material. If the weight-average molecular weight is too high, it will increase the processing difficulty; if the weight-average molecular weight is too low, it will lead to insufficient mechanical properties of the modified polypropylene resin.

[0134] In some embodiments of this application, 15 to 25 parts of filler are also included; the filler may include at least one of talc, light calcium carbonate, and silica. Talc, light calcium carbonate, and silica can be used as reinforcing fillers in polypropylene resin polymerization systems to ensure the excellent mechanical properties of polypropylene materials.

[0135] In some embodiments of this application, the average particle size of the filler can range from 2000 mesh to 3000 mesh.

[0136] By adopting the above scheme, the average particle size range corresponding to the above mesh size is 4.75μm to 3.33μm. The filler in this particle size range has a higher specific surface area, which can better combine with polypropylene resin, improve the dispersibility of filler and polypropylene resin, and thus improve the mechanical properties of polypropylene material.

[0137] In some embodiments of this application, 0.1 to 0.5 parts of a stabilizer are also included.

[0138] By adopting the above approach, the addition of stabilizers can exert a highly efficient synergistic effect, alleviate the aging and degradation of polypropylene materials, and maintain the good mechanical properties of polypropylene materials.

[0139] In some embodiments of this application, the stabilizer includes hindered phenolic antioxidants, phosphite antioxidants, and hindered amine light stabilizers. Further, the mass ratio of the hindered phenolic antioxidant, phosphite antioxidant, and hindered amine light stabilizer can range from 1:(1-4):1.

[0140] By employing the above-mentioned scheme, the hindered phenolic primary antioxidant, the phosphite secondary antioxidant, and the hindered amine light stabilizer are compounded in a specific ratio. These three components work synergistically to effectively and continuously stabilize free radicals, thereby mitigating the aging and degradation process of polypropylene materials and reducing their irritating odor and VOC content. Simultaneously, the use of this three-component stabilizer combination also helps maintain the good mechanical properties of the polypropylene material.

[0141] In some embodiments of this application, the hindered phenolic primary antioxidant includes at least one of pentaerythritol tetrakis[β-(3,5-di-tert-butyl-4-hydroxyphenyl)propionate], 1,3,5-trimethyl-2,4,6-(3,5-di-tert-butyl-4-hydroxyphenylmethyl)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.

[0142] Understandably, pentaerythritol tetrakis[β-(3,5-di-tert-butyl-4-hydroxyphenyl)propionate] (1010), 1,3,5-trimethyl-2,4,6-(3,5-di-tert-butyl-4-hydroxyphenylmethyl)benzene (1330), and 1,3,5-tris(4-tert-butyl-3-hydroxy-2,6-dimethylbenzyl)-1,3,5-triazine-2,4,6-(1H,3H,5H)-trione (1790) can capture free radicals, interrupt the oxidation chain reaction, and thus delay the antioxidant process of polypropylene resin.

[0143] In some embodiments of this application, the phosphite co-antioxidant includes at least one of tris[2,4-di-tert-butylphenyl] phosphite, bis(2,4-di-tert-butylphenyl) pentaerythritol diphosphite, and bis(2,4-dicumylphenyl) pentaerythritol-diphosphite.

[0144] It is understandable that tris[2,4-di-tert-butylphenyl]phosphite, bis(2,4-di-tert-butylphenyl)pentaerythritol diphosphite, or bis(2,4-dicumylphenyl)pentaerythritol-diphosphite, as auxiliary antioxidants, have a synergistic effect with hindered phenolic primary antioxidants, which can more effectively inhibit the oxidation reaction of polypropylene materials and reduce the release of odor and VOC content of polypropylene resin during polymerization modification.

[0145] In some embodiments of this application, 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]}, N,N”'-1,2-ethylenedimethyldi[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”-di(1,2,2,6,6-pentamethyl-4-piperidinyl)-1,3,5-triazine-2,4,6-triamine].

[0146] It is understandable that the degradation process of polypropylene resin will generate free radicals, such as alkoxy radicals and hydroperoxides. Hindered amine light stabilizers capture alkoxy radicals and decompose hydroperoxides. Moreover, hindered amine light stabilizers and hindered phenolic main antioxidants have a synergistic effect, which is beneficial to improving the mechanical properties of polypropylene materials.

[0147] In some embodiments of this application, 0.1 to 1 part of an acid absorbent is also included.

[0148] It should be noted that during the early polymerization process of polypropylene resin, there will inevitably be residues of monomers, oligomers, solvents and catalysts. These residues contain small-molecule acidic substances. During the subsequent processing and use of polypropylene resin, these small-molecule acidic substances will further volatilize. Adding an acid scavenger helps to adsorb these volatile substances, thereby enabling the prepared polypropylene material to have the characteristics of low odor and low VOC content.

[0149] In some embodiments of this application, the acid absorber may also include at least one of metal oxides, lactates, benzoates, silicates, stearates, and hydrotalcites.

[0150] By adopting the above scheme, metal oxides, lactates, benzoates, silicates, stearates, or hydrotalcites can be used as acid absorbers to adsorb acidic substances, thereby reducing the odor and VOC content in the final product, polypropylene material.

[0151] In some embodiments of this application, 0.1 to 3 parts of an additive are also included; the additive may include at least one of carbon black and lubricant.

[0152] By adopting the above scheme, carbon black can be used as a multifunctional additive to significantly improve the UV resistance, electrical conductivity, mechanical properties and thermal stability of polypropylene materials.

[0153] Fourthly, this application provides a method for preparing a polypropylene material, which is used to prepare the aforementioned polypropylene material.

[0154] The preparation method includes the following steps:

[0155] Polypropylene resin, filler, stabilizer, molecular sieve supported photocatalyst, activated carbon fiber supported photocatalyst, acid absorber and additives are mixed and then melt-extruded and granulated to obtain polypropylene material.

[0156] In some embodiments of this application, the melt extrusion temperature can be from 160°C to 210°C. Exemplarily, the melt extrusion temperature can be 160°C, 170°C, 180°C, 190°C, 200°C, 210°C, or any value between two adjacent values.

[0157] In some embodiments of this application, the melt extrusion pressure is from 12 MPa to 18 MPa. Exemplarily, the melt extrusion pressure can be 12 MPa, 13 MPa, 14 MPa, 15 MPa, 16 MPa, 17 MPa, 18 MPa, or any value between two adjacent values.

[0158] Fifthly, this application provides an automotive interior component comprising the aforementioned polypropylene material.

[0159] Understandably, the low odor and low VOC content of polypropylene materials have broadened their application range, making them suitable for use in automotive interior parts.

[0160] In some embodiments of this application, automotive interior components may include at least one of a dashboard, instrument panel, door panel, pillar trim, and seat back panel.

[0161] The present application will be specifically described below through specific embodiments. These embodiments are only some embodiments of the present application and are not intended to limit the present application. Unless otherwise specified, the raw materials used in the following embodiments are all commercially available products.

[0162] Example 1

[0163] A polypropylene material, comprising the following steps:

[0164] S100, Preparation of molecular sieve-supported silver bromide / bismuth oxybromide:

[0165] S101. Dissolve 7.3g of bismuth nitrate pentahydrate in 250mL of ethylene glycol and stir to obtain a bismuth nitrate pentahydrate solution;

[0166] S102. Dissolve 5.1g of silver nitrate and 3.6g of potassium bromide in 100mL of deionized water and stir to obtain silver nitrate solution and potassium bromide solution respectively.

[0167] S103. Then add silver nitrate solution to bismuth nitrate pentahydrate solution and stir to obtain the first mixture;

[0168] S104. Add potassium bromide solution to the first mixture and stir in a 90°C water bath for 2 hours to obtain the second mixture.

[0169] S105. Add 64g of molecular sieve to the second mixture and continue ultrasonic stirring to obtain the first mixture.

[0170] S106. Cool the first mixture to room temperature and wash it with ethanol and deionized water to obtain the washings.

[0171] S107. Place the washed material in an oven and dry it at 80°C for 12 hours. Then place it in a muffle furnace and calcine it at 500°C for 6 hours to obtain molecular sieve-supported silver bromide / bismuth oxybromide.

[0172] S200, Preparation of activated carbon fiber supported on manganese dioxide:

[0173] S201. Add 50g of activated carbon fiber to 500mL of 2wt% manganese nitrate solution and stir to obtain a second mixture;

[0174] S202. Then the second mixture is dried in an oven at 100°C for 12 hours, and then calcined in a muffle furnace at 500°C for 6 hours to obtain activated carbon fiber loaded with manganese dioxide.

[0175] S300, Preparation of stabilizer:

[0176] A stabilizer was prepared by mixing 1,3,5-tris(4-tert-butyl-3-hydroxy-2,6-dimethylbenzyl)-1,3,5-triazine-2,4,6-(1H,3H,5H)-trione, bis(2,4-dicumylphenyl)pentaerythritol-diphosphite, and poly-{[6-[(1,1,3,3-tetramethylbutyl)-imino]-1,3,5-triazine-2,4-diyl][2-(2,2,6,6-tetramethylpiperidinyl)-amino]-hexene-[4-(2,2,6,6-tetramethylpiperidinyl)-imino]} in a mass ratio of 1:2:1.

[0177] S400, Preparation of polypropylene materials

[0178] S401 provides 7.7 kg of polypropylene resin, 2.0 kg of talc, 0.05 kg of stabilizer, 0.02 kg of calcium stearate, 0.1 kg of molecular sieve-supported silver bromide / bismuth oxybromide, 0.1 kg of activated carbon fiber-supported manganese dioxide, and 0.03 kg of carbon black;

[0179] S402. Add the above components to a high-speed mixer and mix for 10 minutes until uniform. Then add the mixture to a twin-screw extruder for melt extrusion. The temperatures of each zone of the twin-screw extruder are as follows: Zones 1-2: 120℃, Zones 3-5: 180℃, Zones 6-9: 200℃, Die head temperature: 210℃, Extrusion pressure: 15MPa, Main screw speed: 600r / min, Vacuum degree: not less than 0.08MPa. After melt extrusion, cooling, granulation, and drying, polypropylene material is obtained.

[0180] Example 2

[0181] A polypropylene material differs from Example 1 in that the content of each component in the formulation is different. The polypropylene material of this example comprises the following components by mass:

[0182] 7.0 kg of polypropylene resin, 2.8 kg of talc, 0.05 kg of stabilizer, 0.02 kg of calcium stearate, 0.05 kg of molecular sieve-supported silver bromide / bismuth oxybromide, 0.05 kg of activated carbon fiber-supported manganese dioxide, and 0.03 kg of carbon black.

[0183] Example 3

[0184] A polypropylene material differs from Example 1 in that the content of each component in the formulation is different. The polypropylene material of this example comprises the following components by mass:

[0185] 8 kg of polypropylene resin, 1.5 kg of talc, 0.05 kg of stabilizer, 0.02 kg of calcium stearate, 0.2 kg of molecular sieve-supported silver bromide / bismuth oxybromide, 0.2 kg of activated carbon fiber-supported manganese dioxide, and 0.03 kg of carbon black.

[0186] Example 4

[0187] A polypropylene material differs from Example 1 in that the mass ratio of molecular sieve-loaded silver bromide / bismuth oxybromide to activated carbon fiber-loaded manganese dioxide is different. In this example, the mass ratio of molecular sieve-loaded silver bromide / bismuth oxybromide to activated carbon fiber-loaded manganese dioxide is 0.5.

[0188] Example 5

[0189] A polypropylene material differs from Example 1 in that the mass ratio of molecular sieve-loaded silver bromide / bismuth oxybromide to activated carbon fiber-loaded manganese dioxide is different. In this example, the mass ratio of molecular sieve-loaded silver bromide / bismuth oxybromide to activated carbon fiber-loaded manganese dioxide is 2.

[0190] Example 6

[0191] A polypropylene material differs from Example 1 in that the mass ratio of molecular sieve-loaded silver bromide / bismuth oxybromide to activated carbon fiber-loaded manganese dioxide is different. In this example, the mass ratio of molecular sieve-loaded silver bromide / bismuth oxybromide to activated carbon fiber-loaded manganese dioxide is 1 / 3.

[0192] Example 7

[0193] A polypropylene material differs from Example 1 in that the mass ratio of molecular sieve-loaded silver bromide / bismuth oxybromide to activated carbon fiber-loaded manganese dioxide is different. In this example, the mass ratio of molecular sieve-loaded silver bromide / bismuth oxybromide to activated carbon fiber-loaded manganese dioxide is 3.

[0194] Example 8

[0195] A polypropylene material differs from Example 1 in that it uses a different stabilizer. The stabilizer in this example is prepared using a mass ratio of 1790:168:119 of 1:2:1.

[0196] Example 9

[0197] A polypropylene material differs from Example 1 in that it uses a different stabilizer. The stabilizer in this example is prepared using a mass ratio of 1330:686:119 of 1:2:1.

[0198] Example 10

[0199] A polypropylene material differs from that of Example 1 in that it uses a different stabilizer. The stabilizer in this example is prepared using a mass ratio of 1790:686:944 (1:2:1).

[0200] Example 11

[0201] A polypropylene material differs from that of Example 1 in that it uses a different stabilizer. The stabilizer in this example is prepared using a mass ratio of 1330:168:119 of 1:2:1.

[0202] Example 12

[0203] A polypropylene material differs from that of Example 10 in that it uses a different composite photocatalyst. In this example, the composite photocatalyst is a mixture of chromium trioxide supported on activated carbon fibers and silver chloride / bismuth oxychloride supported on molecular sieves.

[0204] Example 13

[0205] A polypropylene material differs from that of Example 10 in that the composite photocatalyst is different. In this example, the composite photocatalyst is a mixture of chromium trioxide supported on activated carbon fibers and silver bromide / bismuth oxybromide supported on molecular sieves.

[0206] Example 14

[0207] A polypropylene material differs from Example 1 in that both the stabilizer and the composite photocatalyst are different. In this example, the stabilizer is prepared using a mass ratio of 1:2:1 (1330:686:944). The composite photocatalyst in this example is a mixture of activated carbon fiber-supported manganese dioxide and molecular sieve-supported silver chloride / bismuth oxychloride.

[0208] Example 15

[0209] A polypropylene material differs from that of Example 14 in that the composite photocatalyst is different. In this example, the composite photocatalyst is a mixture of chromium trioxide supported on activated carbon fibers and silver chloride / bismuth oxychloride supported on molecular sieves.

[0210] Example 16

[0211] A polypropylene material differs from that of Example 10 in that the content of some components in the formulation is different. The polypropylene material of this example comprises the following components by mass:

[0212] 7.6 kg of polypropylene resin, 2.0 kg of talc, 0.05 kg of stabilizer, 0.02 kg of calcium stearate, 0.2 kg of molecular sieve-supported silver chloride / bismuth oxychloride, 0.1 kg of activated carbon fiber-supported manganese dioxide, and 0.03 kg of carbon black.

[0213] Example 17

[0214] A polypropylene material differs from Example 9 in that the content of some components in the formulation is different. The polypropylene material of this example comprises the following components by mass:

[0215] 7.6 kg of polypropylene resin, 2.0 kg of talc, 0.05 kg of stabilizer, 0.02 kg of calcium stearate, 0.1 kg of molecular sieve-supported silver chloride / bismuth oxychloride, 0.2 kg of activated carbon fiber-supported manganese dioxide, and 0.03 kg of carbon black.

[0216] Example 18

[0217] A polypropylene material differs from Example 9 in that the content of some components in the formulation is different. The polypropylene material of this example comprises the following components by mass:

[0218] 7.6 kg of polypropylene resin, 2.0 kg of talc, 0.05 kg of stabilizer, 0.02 kg of calcium stearate, 0.2 kg of molecular sieve-supported silver bromide / bismuth oxybromide, 0.1 kg of activated carbon fiber-supported chromium trioxide, and 0.03 kg of carbon black.

[0219] Example 19

[0220] A polypropylene material differs from Example 9 in that the content of some components in the formulation is different. The polypropylene material of this example comprises the following components by mass:

[0221] 7.5 kg of polypropylene resin, 2.0 kg of talc, 0.05 kg of stabilizer, 0.02 kg of calcium stearate, 0.2 kg of molecular sieve-supported silver chloride / bismuth oxychloride, 0.2 kg of activated carbon fiber-supported manganese dioxide, and 0.03 kg of carbon black.

[0222] Example 20

[0223] A polypropylene material differs from that of Example 10 in that the content of some components in the formulation is different. The polypropylene material of this example comprises the following components by mass:

[0224] 7.5 kg of polypropylene resin, 2.0 kg of talc, 0.05 kg of stabilizer, 0.02 kg of calcium stearate, 0.2 kg of molecular sieve-supported silver chloride / bismuth oxychloride, 0.2 kg of activated carbon fiber-supported manganese dioxide, and 0.03 kg of carbon black.

[0225] Comparative Example 1

[0226] A polypropylene material differs from that in Example 1 in that its formulation is different. The formulation of this comparative example is 7.7 kg of polypropylene resin, 2.0 kg of talc, 0.01 kg of primary antioxidant 1010, 0.02 kg of secondary antioxidant 168, and 0.03 kg of carbon black.

[0227] Comparative Example 2

[0228] A polypropylene material differs from that in Example 1 in that its formulation is different. The formulation of this comparative example is 7.7 kg of polypropylene resin, 2.0 kg of talc, 0.01 kg of primary antioxidant 1010, 0.02 kg of secondary antioxidant 168, 0.1 kg of molecular sieve, and 0.03 kg of carbon black.

[0229] Comparative Example 3

[0230] A polypropylene material differs from that in Example 1 in that its formulation is different. The formulation of this comparative example is 7.7 kg of polypropylene resin, 2.0 kg of talc, 0.01 kg of primary antioxidant 1010, 0.02 kg of secondary antioxidant 168, 0.1 kg of molecular sieve-supported silver bromide / bismuth oxybromide, and 0.03 kg of carbon black.

[0231] Comparative Example 4

[0232] A polypropylene material differs from that in Example 1 in that its formulation is different. The formulation of this comparative example is 7.7 kg of polypropylene resin, 2.0 kg of talc, 0.01 kg of primary antioxidant 1010, 0.02 kg of secondary antioxidant 168, 0.1 kg of activated carbon fiber, and 0.03 kg of carbon black.

[0233] Comparative Example 5

[0234] A polypropylene material differs from that in Example 1 in that its formulation is different. The formulation of this comparative example is 7.7 kg of polypropylene resin, 2.0 kg of talc, 0.01 kg of primary antioxidant 1010, 0.02 kg of secondary antioxidant 168, 0.1 kg of activated carbon fiber-supported manganese dioxide, and 0.03 kg of carbon black.

[0235] Detection method:

[0236] The polypropylene materials prepared as described in the examples and comparative examples were subjected to the following relevant performance tests:

[0237] (1) Melt flow rate:

[0238] The melt index rate of the samples was tested in accordance with GB / T 3682.1-2018;

[0239] (2) Mechanical properties:

[0240] The tensile strength, flexural modulus and notched impact strength of the specimens were tested in accordance with GB / T 1040-92 and GB / T 1043-93. The specimen conditioning and test standard environment were carried out in accordance with GB / T 2918-1998, at (23±2)℃ and (50±5)% relative humidity, and the specimen conditioning time was 48h.

[0241] (3) Odor test:

[0242] Referring to the Q / BYDQ A 1901.404 018 standard, a 1L container containing 20g of sample was placed in an electric thermostatic drying oven at 80±2℃ and heated for 120±10min. After removing the container, it was cooled to 60±5℃. During evaluation, the evaluator's nose was 2-3cm away from the open container opening. Then, the container lid was opened, and the evaluator inhaled normally. The opening time should not exceed 10s. The evaluation was conducted by three groups of people, and the arithmetic mean of the evaluation results was taken. The evaluation criteria are shown in Table 1.

[0243] Table 1 Odor Rating Criteria

[0244]

[0245] (4) VOC testing

[0246] Referencing Q / BYDQ A1901.771 2023 standard, the bag method was used to determine VOC and TVOC content. The sample was placed in a 10L sampling bag, filled with approximately 5L of high-purity nitrogen, and then heated in an electrically heated constant-temperature drying oven at 65℃ for 2 hours. The gas from the bag was collected into a Tenax tube at a sampling pump at a rate of 100ml / min for 10 minutes, and then into a DNPH tube at a rate of 400ml / min for 2 minutes. After sampling, the volatile organic components and aldehyde / ketone components were qualitatively and quantitatively analyzed using thermal desorption-gas chromatography-mass spectrometry (TD-GC-MS) and high-performance liquid chromatography (HPLG), respectively.

[0247] The detection results of the examples and comparative examples are shown in Table 2.

[0248] Table 2

[0249]

[0250]

[0251] Based on Examples 1-3 and Comparative Examples 1-5, it can be seen that in Examples 1-3, the addition of a molecular sieve-supported silver bromide / bismuth oxybromide and activated carbon fiber-supported manganese dioxide composite as a photocatalyst can decompose benzene and aldehyde VOCs in polypropylene materials and reduce odor. The benzene VOC content is 0.46–0.58 μg / m³. 3 The aldehyde VOC content is 0.28–0.35 μg / m³. 3The PP odor rating was 3.5. In contrast, Comparative Example 1 (without additional photocatalyst), Comparative Example 2 (using molecular sieve adsorption), Comparative Example 4 (using activated carbon fiber adsorption), Comparative Example 3 (only adding molecular sieve-supported silver bromide / bismuth oxybromide), and Comparative Example 5 (only adding activated carbon fiber-supported manganese dioxide) all showed significantly higher VOC content and odor ratings, with a benzene VOC content of 0.8 μg / m³. 3 The above, or the aldehyde VOC content is 0.6 μg / m³ 3 The above items have an odor rating of 3.7 or higher, and their mechanical properties have decreased to varying degrees.

[0252] Combining Examples 4-7 with Example 1, it can be seen that Examples 4-7, by changing the mass ratio of molecular sieve-supported silver bromide / bismuth oxybromide to activated carbon fiber-supported manganese dioxide, can slightly reduce the content of benzene-based VOCs and aldehyde-based VOCs. Comparing Example 6 with Example 4, the mass ratio of molecular sieve-supported silver bromide / bismuth oxybromide to activated carbon fiber-supported manganese dioxide in Example 6 is 1 / 3. Referring to Table 2, it can be seen that the mechanical properties of the polypropylene material are basically unaffected, but the adsorption of benzene-based VOCs is reduced.

[0253] Compared with Example 1, Examples 8-11 changed the types of primary antioxidant, secondary antioxidant and light stabilizer. According to Table 2, the stabilizers are preferably a combination of 1790, 686 and 944 to minimize the odor and VOC content of the polypropylene material. The odor can reach level 3.3.

[0254] Compared to Example 10, Examples 12-13 changed the type of composite photocatalyst. As shown in Table 2, Examples 12-13 exhibited lower VOC content and higher tensile strength and flexural modulus compared to Example 10.

[0255] Compared with Example 1, Examples 14-15 differed in that the types of stabilizer and photocatalyst were changed. As shown in Table 2, the VOC content of Examples 14-15 was significantly reduced, and the odor level of Example 15 was significantly lower, indicating that the combination of stabilizer and photocatalyst can exert a synergistic effect and greatly improve the emission performance of PP.

[0256] Compared with Examples 9-10, Examples 16-20 increased the content of molecular sieve-supported photocatalyst or activated carbon fiber-supported photocatalyst. As shown in Table 2, the odor level of Examples 16-20 was significantly reduced, reaching level 3.0; the VOC content was also significantly reduced, reaching the undetectable standard. These results indicate that increasing the content of molecular sieve-supported photocatalyst or activated carbon fiber-supported photocatalyst can effectively remove odors and reduce VOC content.

[0257] The composite photocatalyst, polypropylene material, preparation method, and automotive interior parts provided in the embodiments of this application have been described in detail above. Specific examples have been used to illustrate the principles and implementation methods of the present invention. The descriptions of the above embodiments are only for the purpose of helping to understand the methods and core ideas of the present invention. At the same time, for those skilled in the art, there will be changes in the specific implementation methods and application scope based on the ideas of the present invention. Therefore, the content of this specification should not be construed as a limitation of the present invention.

Claims

1. A composite photocatalyst, characterized in that, The composite photocatalyst comprises the following components: Molecular sieve-supported silver halide / bismuth halide; and Activated carbon fibers loaded with transition metal oxides.

2. The composite photocatalyst according to claim 1, characterized in that, The mass ratio of the molecular sieve-loaded silver halide / bismuth halide to the activated carbon fiber-loaded transition metal oxide ranges from 0.5 to 2.

3. The composite photocatalyst according to claim 1, characterized in that, The molecular sieve includes at least one of ZSM-5 type molecular sieve, type A molecular sieve, type X molecular sieve, type Y molecular sieve, mesoporous molecular sieve, and hydrophobic molecular sieve; Preferably, the molecular sieve includes ZSM-5 type molecular sieve or hydrophobic molecular sieve.

4. The composite photocatalyst according to claim 1, characterized in that, The silver halide includes at least one of silver chloride, silver bromide, and silver iodide; and / or The bismuth oxyhalide includes at least one of bismuth oxychloride, bismuth oxybromide, and bismuth oxyiodide.

5. The composite photocatalyst according to claim 1, characterized in that, The transition metal oxides include at least one of manganese oxide, chromium oxide, cobalt oxide, zinc oxide, vanadium oxide, and zirconium oxide. Preferably, the transition metal oxide includes manganese oxide or chromium oxide.

6. The composite photocatalyst according to claim 1, characterized in that, The activated carbon fibers have a diameter of 5 μm to 10 μm; and / or The specific surface area of ​​the activated carbon fiber is 1800 m². 2 / g to 2200m 2 / g; and / or The activated carbon fiber has a pore size of 1 nm to 2 nm.

7. A method for preparing a composite photocatalyst, the method being used to prepare the composite photocatalyst according to any one of claims 1 to 6, wherein the molecular sieve-supported silver halide / bismuth halide is prepared by the following steps: The bismuth salt is dissolved in the first solvent and stirred to obtain a bismuth salt solution; Silver salt and potassium halide were dissolved separately in a second solvent and stirred to obtain silver salt solution and potassium halide solution; The silver salt solution was added to the bismuth salt solution and stirred to obtain the first mixture; Then, potassium halide solution is added to the first mixture, and the mixture is heated and stirred to obtain the second mixture. Then add molecular sieves to the second mixture and continue stirring to obtain the first mixture; The first mixture was cooled, dried, and calcined to obtain molecular sieve-supported silver halide / bismuth halide.

8. A method for preparing a composite photocatalyst, the method being used to prepare the composite photocatalyst according to any one of claims 1 to 6, wherein the activated carbon fiber-supported transition metal oxide is prepared by the following steps: Activated carbon fibers were added to a transition metal salt solution and stirred to obtain a second mixture; The second mixture was dried and calcined to obtain activated carbon fibers loaded with transition metal oxides.

9. A polypropylene material, characterized in that, The polypropylene material comprises the following components in parts by weight: 70 to 80 parts of polypropylene resin; 0.5 to 2 parts of molecular sieve-supported photocatalyst; 0.5 to 2 parts of activated carbon fiber supported photocatalyst.

10. The polypropylene material according to claim 9, characterized in that, The molecular sieve-supported photocatalyst includes molecular sieve-supported silver halide / bismuth halide; and / or The activated carbon fiber supported photocatalyst includes activated carbon fiber supported transition metal oxides; Preferably, the mass ratio of the molecular sieve-supported silver halide / bismuth halide to the activated carbon fiber-supported transition metal oxide ranges from 0.5 to 2.

11. The polypropylene material according to claim 9 or 10, characterized in that, The molecular sieve includes at least one of ZSM-5 type molecular sieve, type A molecular sieve, type X molecular sieve, type Y molecular sieve, mesoporous molecular sieve, and hydrophobic molecular sieve; Preferably, the molecular sieve includes ZSM-5 type molecular sieve or hydrophobic molecular sieve.

12. The polypropylene material according to claim 10, characterized in that, The silver halide includes at least one of silver chloride, silver bromide, and silver iodide; and / or The bismuth oxyhalide includes at least one of bismuth oxychloride, bismuth oxybromide, and bismuth oxyiodide.

13. The polypropylene material according to claim 10, characterized in that, The transition metal oxides include at least one of manganese oxide, chromium oxide, cobalt oxide, zinc oxide, vanadium oxide, and zirconium oxide. Preferably, the transition metal oxide includes manganese oxide or chromium oxide.

14. The polypropylene material according to claim 9, characterized in that, The activated carbon fibers have a diameter of 5 μm to 10 μm; and / or The specific surface area of ​​the activated carbon fiber is 1800 m². 2 / g to 2200m 2 / g; and / or The activated carbon fiber has a pore size of 1 nm to 2 nm.

15. The polypropylene material according to claim 9, characterized in that, The polypropylene resin is prepared using a hydrogen conditioning method and a Spherizone / Spheripol process; and / or The weight-average molecular weight of the polypropylene resin ranges from 200,000 to 350,000.

16. The polypropylene material according to claim 9, characterized in that, It also includes 15 to 25 parts of filler; said filler includes at least one of talc, light calcium carbonate, and silicon dioxide; Preferably, the average particle size of the filler is in the range of 2000 mesh to 3000 mesh.

17. The polypropylene material according to claim 9, characterized in that, It also includes 0.1 to 0.5 parts of stabilizer; the stabilizer includes hindered phenolic antioxidant, phosphite antioxidant and hindered amine light stabilizer; preferably, the mass ratio of the hindered phenolic antioxidant, phosphite antioxidant and hindered amine light stabilizer is in the range of 1:(1-4):

1.

18. The polypropylene material according to claim 17, characterized in that, The hindered phenolic primary antioxidant includes at least one of pentaerythritol tetrakis[β-(3,5-di-tert-butyl-4-hydroxyphenyl)propionate], 1,3,5-trimethyl-2,4,6-(3,5-di-tert-butyl-4-hydroxyphenylmethyl)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.

19. The polypropylene material according to claim 17, characterized in that, The phosphite-based antioxidant includes at least one of tris[2,4-di-tert-butylphenyl] phosphite, bis(2,4-di-tert-butylphenyl) pentaerythritol diphosphite, and bis(2,4-dicumylphenyl) pentaerythritol-diphosphite.

20. The polypropylene material according to claim 17, characterized in that, 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]}, N,N”'-1,2-ethylenedimethyldi[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”-di(1,2,2,6,6-pentamethyl-4-piperidinyl)-1,3,5-triazine-2,4,6-triamine].

21. The polypropylene material according to claim 9, characterized in that, It also includes 0.1 to 1 part of an acid absorbent; The acid absorbent includes at least one of metal oxides, lactates, benzoates, silicates, stearates, and hydrotalcite.

22. The polypropylene material according to claim 9, characterized in that, It also includes 0.1 to 3 parts of additives; said additives include at least one of carbon black and lubricant.

23. A method for preparing a polypropylene material, said preparation method being used to prepare the polypropylene material according to any one of claims 9 to 22, characterized in that, The preparation method includes the following steps: Polypropylene resin, filler, stabilizer, molecular sieve supported photocatalyst, activated carbon fiber supported photocatalyst, acid absorber and additives are mixed and then melt-extruded and granulated to obtain polypropylene material.

24. The method for preparing polypropylene material according to claim 23, characterized in that, The melt extrusion temperature is 160°C to 210°C; and / or The pressure of the melt extrusion is 12 MPa to 18 MPa.

25. An automotive interior trim component, characterized in that, The automotive interior components include the polypropylene material as described in any one of claims 9 to 22.

26. The automotive interior trim component according to claim 25, characterized in that, The automotive interior components include at least one of the following: dashboard, instrument panel, door panel, pillar trim, and seat trim.

Images