Modified polypropylene containing reworked material PCR (Polymerase Chain Reaction) and preparation method thereof

Abstract

The invention provides modified polypropylene containing reclaimed material PCR (Polymerase Chain Reaction) and a preparation method, and belongs to the field of high polymer materials. The modified polypropylene comprises the following raw materials: more than 0 part and less than or equal to 50 parts of polypropylene reclaimed material, 5-15 parts of modified polyolefin, 0.5-2.5 parts of chemically activated carbon powder, 5-25 parts of filler, 0.1-1 part of fragrant substance and 10-70 parts of polypropylene. On one hand, modified polyethylene is used as a compatilizer to be applied to the system, so that the compatibility between the polypropylene reclaimed material and polypropylene can be improved; on the other hand, the functional activated carbon powder is added into the raw materials to adsorb small molecules and odor substances in the material, and meanwhile, a certain amount of the odor substances are added, so that the odor perception is improved while the odor of the material is improved. Therefore, the smell of the modified polypropylene containing the regenerated material PCR is improved while the compatibility between the regenerated material and the new material is improved.

Description

Technical Field

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

[0002] Modified polypropylene containing recycled material PCR refers to a plastic material obtained by mixing and modifying post-consumer recycled polypropylene (PCR) with new polypropylene materials or other additives. Recycled material PCR mainly comes from waste plastic products, such as plastic bags, plastic bottles, plastic boxes, etc., which are obtained after recycling, cleaning, crushing, melting and other processes. With the improvement of environmental awareness and the increasing shortage of resources, the application field of modified polypropylene containing recycled material PCR will continue to expand, and the market demand will continue to grow. At the same time, with the advancement of technology and the reduction of costs, its performance will continue to improve to meet the needs of more high-end applications.

[0003] By applying recycled polypropylene materials to automobiles, we can reduce environmental pollution, lower living production costs and operating costs, and achieve resource recycling and green and low-carbon development. However, when developing PCR-PP materials for automotive interior parts, there are deviations in compatibility, strength, toughness, etc. between recycled materials (PCR) and new materials PP, which will affect the performance of the final PCR-PP materials. Other additives need to be added to improve the compatibility between recycled materials PCR and new materials PP; at the same time, the odor of recycled materials is relatively poor, and the odor of the materials needs to be improved and the odor perception needs to be enhanced before they can be used for interior parts. Therefore, how to improve the compatibility between recycled materials and new materials while improving the odor of modified polypropylene containing recycled materials PCR is a technical problem that urgently needs to be solved. Summary of the invention

[0004] The present application provides a modified polypropylene containing recycled material PCR and a preparation method thereof to solve the following technical problem: how to improve the odor of the modified polypropylene containing recycled material PCR while improving the compatibility between recycled material and new material.

[0005] In the first aspect, the present application provides a modified polypropylene containing recycled material PCR. The raw materials of the modified polypropylene include, in parts by weight: polypropylene recycled material >0 parts and ≤50 parts, modified polyolefin 5 parts to 15 parts, chemically activated carbon powder 0.5 parts to 2.5 parts, filler 5 parts to 25 parts, flavoring substance 0.1 parts to 1 parts and polypropylene 10 parts to 70 parts.

[0006] Optionally, the iodine adsorption value of the chemically activated carbon powder is greater than 1200 mg / g, and the mesh size of the chemically activated carbon powder is less than 200 meshes.

[0007] Optionally, the raw materials of the modified polyolefin include: polyolefin, monomer and initiator; wherein the weight of the monomer is 0.5% to 5% of the total weight of the modified polyolefin, and the weight of the initiator is 0.02% to 0.08% of the weight of the polyolefin.

[0008] Optionally, the polyolefin includes one or more of ethylene-propylene copolymer, polyethylene, polybutene, polypentene, polyoctene, propylene-butene copolymer, ethylene-butene copolymer and octene-ethylene copolymer; and / or,

[0009] The monomers include: one or more of acrylate, maleic anhydride, acrylic acid, nadic anhydride and bismaleimide; and / or,

[0010] The initiator includes one or more of dicumyl peroxide, azobisisobutyronitrile and bis-2,5-hexane.

[0011] Optionally, the polyolefin is a polyethylene and octene-ethylene copolymer, and the weight ratio of the polyethylene to the octene-ethylene is (1-5):1.

[0012] Optionally, the filler includes: one or more of talc, calcium carbonate, barium sulfate, white carbon black, bentonite, attapulgite and starch; and / or,

[0013] The polypropylene includes: one or more of homopolymer polypropylene, random copolymer polypropylene and impact copolymer polypropylene; and / or,

[0014] The aroma substance includes: n-butyl acetate.

[0015] Optionally, the raw materials of the modified polypropylene further include, by weight: 0.1 to 1 part of an antioxidant, 0.1 to 0.3 part of an anti-UV agent, and 0.1 to 1 part of a lubricant.

[0016] Optionally, the modified polypropylene satisfies at least one of the following properties:

[0017] Tensile strength ≥18.5MPa;

[0018] Flexural modulus ≥1890MPa;

[0019] Izod beam notched impact strength ≥40kJ / m 2 ;

[0020] Melt index ≥26.5g / 10min;

[0021] Odor intensity ≤ level 3.5.

[0022] In a second aspect, the present application provides a method for preparing the modified polypropylene as described in any one embodiment of the first aspect, the method comprising:

[0023] The polypropylene recycled material, modified polyolefin, antioxidant, UV inhibitor, chemically activated carbon powder, filler, lubricant, fragrance material and polypropylene are mixed according to weight parts to obtain a mixed material;

[0024] The mixed material is melt-extruded and granulated to obtain the modified polypropylene; the temperature of the melt-extrusion is 180° C. to 250° C., and the rotation speed of the melt-extrusion is 100 rad / min to 300 rad / min.

[0025] Optionally, the preparation method of the activated carbon powder comprises:

[0026] The carbon material is immersed in a strong alkali or oxidant solution and then dried to obtain a precursor;

[0027] The precursor is heat-treated to obtain activated carbon powder; the heat treatment temperature is 600° C. to 900° C., and the heat treatment time is 2 h to 3 h.

[0028] The above technical solution provided by the embodiment of the present application has the following advantages compared with the prior art:

[0029] The present application provides a modified polypropylene containing recycled material PCR. The raw materials of the modified polypropylene include, by weight: polypropylene recycled material >0 part and ≤50 parts, modified polyolefin 5 parts to 15 parts, chemically activated carbon powder 0.5 parts to 2.5 parts, filler 5 parts to 25 parts, flavoring substance 0.1 parts to 1 part and polypropylene 10 parts to 70 parts; wherein the compatibilizer is modified polyolefin; the activated carbon powder is chemically activated carbon powder. On the one hand, by modifying polyethylene with monomers to obtain modified polyethylene, and using it as a compatibilizer in this system, the compatibility between polypropylene recycled materials and polypropylene can be improved, thereby reducing the impact of the addition of recycled materials on the performance of the prepared modified polypropylene, and meeting the requirements of automotive parts for material strength and stiffness; on the other hand, adding high-porosity and high-activity functional activated carbon powder to the raw materials, adsorbing small molecules and odor substances in the materials, and adding a certain amount of fragrance substances, while improving the odor of the materials and enhancing the odor perception, making it easier for recycled materials to be promoted and applied in interior materials, meeting the public's high requirements for the automotive interior environment; in addition, the selection of chemically activated carbon powder and the use of modified polyolefins can make the activated carbon powder well mixed in the raw materials, and have a positive effect on the strength of the materials through dispersion, interface enhancement, molecular chain cross-linking, filling effect and stress dispersion. Thus, while improving the compatibility between recycled materials and new materials, the odor of modified polypropylene containing recycled material PCR is improved. BRIEF DESCRIPTION OF THE DRAWINGS

[0030] The accompanying drawings, which are incorporated in and constitute a part of this specification, illustrate embodiments consistent with the present application and, together with the description, serve to explain the principles of the present application.

[0031] In order to more clearly illustrate the embodiments of the present application or the technical solutions in the prior art, the drawings required for use in the embodiments or the description of the prior art will be briefly introduced below. Obviously, for ordinary technicians in this field, other drawings can be obtained based on these drawings without paying any creative labor.

[0032] Figure 1 A schematic flow chart of a method for preparing modified polypropylene provided in an embodiment of the present application. DETAILED DESCRIPTION

[0033] In order to make the purpose, technical solution and advantages of the embodiments of the present application clearer, the technical solution in the embodiments of the present application will be clearly and completely described below in conjunction with the drawings in the embodiments of the present application. Obviously, the described embodiments are part of the embodiments of the present application, not all of the embodiments. Based on the embodiments in the present application, all other embodiments obtained by ordinary technicians in this field without making creative work are within the scope of protection of this application.

[0034] Various embodiments of the present application may be presented in the form of a range; it should be understood that the description in the form of a range is only for convenience and brevity, and should not be understood as a rigid limitation on the scope of the present application; therefore, the range description should be considered to have specifically disclosed all possible sub-ranges and single numerical values ​​within the range. For example, the range description from 1 to 6 should be considered to have specifically disclosed sub-ranges, such as from 1 to 3, from 1 to 4, from 1 to 5, from 2 to 4, from 2 to 6, from 3 to 6, etc., as well as single numbers within the range, such as 1, 2, 3, 4, 5 and 6, which apply regardless of the range. In addition, whenever a numerical range is indicated herein, it is meant to include any cited number (fractional or integer) within the indicated range.

[0035] In addition, in the description of the specification of the present application, the terms "including", "comprising", etc. mean "including but not limited to". In this article, relational terms such as "first" and "second", etc. are only used to distinguish one entity or operation from another entity or operation, and do not necessarily require or imply any such actual relationship or order between these entities or operations. In this article, "and / or" describes the association relationship of associated objects, indicating that three relationships may exist. For example, A and / or B can represent: A exists alone, A and B exist at the same time, and B exists alone. Wherein A and B can be singular or plural. In this article, "at least one" means one or more, and "plurality" means two or more. "At least one", "the following at least one item (items)" or similar expressions refer to any combination of these items, including any combination of single items (items) or plural items (items). For example, "at least one of a, b, or c", or "at least one of a, b, and c", can all represent: a, b, c, ab (i.e., a and b), ac, bc, or abc, where a, b, c can be single or multiple. "Parts" such as parts by weight and parts by mass indicate the proportional relationship between the components. In the proportional relationship involved in this article, the parameters that need to be described by proportion should be understood as the first term of the proportional formula in the order of description, and the proportional numbers should be understood as the second term of the proportional formula. For example, the mass ratio of substance A, substance B, and substance C is 1:2:3, then substance A, substance B, and substance C should correspond one-to-one with the proportional numbers in the proportional formula in the order of description, that is, the mass of substance A: the mass of substance B: the mass of substance C = 1:2:3.

[0036] Unless otherwise specified, various raw materials, reagents, instruments and equipment used in this application can be purchased from the market or prepared by existing methods.

[0037] The present application provides a modified polypropylene containing recycled material PCR. The raw materials of the modified polypropylene include, by weight: polypropylene recycled material >0 part and ≤50 parts, modified polyolefin 5 parts to 15 parts, chemically activated carbon powder 0.5 parts to 2.5 parts, filler 5 parts to 25 parts, flavoring substance 0.1 parts to 1 part and polypropylene 10 parts to 70 parts.

[0038] In some embodiments, the raw material of the modified polypropylene further includes, by weight: 0.1 to 1 part of an antioxidant, 0.1 to 0.3 part of an anti-UV agent, and 0.1 to 1 part of a lubricant.

[0039] The content of polypropylene recycled material (PCR) is greater than 0 parts and less than or equal to 50 parts, which can provide the main plastic matrix, realize the recycling of resources and reduce environmental pollution. The content of compatibilizer is 5 to 15 parts, which can improve the compatibility between polypropylene recycled material and new polypropylene material, and improve the overall performance and stability of the material. The content of antioxidant is 0.1 to 1 part, which can prevent the material from being degraded due to oxidation during processing and use, and extend the service life. The content of anti-UV agent is 0.1 to 0.3 parts, which can improve the anti-ultraviolet performance of the material and prevent aging, fading and other problems caused by ultraviolet radiation. The content of activated carbon powder is 0.5 to 2.5 parts, which can effectively improve the VOC adsorption capacity of plastic particles and improve other physical and chemical properties of the material. The content of filler is 5 to 25 parts, which can reduce costs, improve processing performance, and improve certain physical properties (such as hardness, wear resistance, etc.). The content of lubricant is 0.1 to 1 part, which can improve the processing fluidity of the material and reduce energy consumption and wear during processing. The content of aromatic substances is 0.1 to 1 parts, which can give the material a specific aroma and improve the added value of the product and user experience. The content of polypropylene: 10 to 70 parts, which can constitute the main part of the material together with polypropylene recycled materials to provide the necessary strength and toughness. Exemplarily, the weight parts of polypropylene recycled materials can be 10 parts, 15 parts, 20 parts, 25 parts, 30 parts, 35 parts, 40 parts, 45 parts, 50 parts, etc., the weight parts of compatibilizers can be 5 parts, 7 parts, 9 parts, 10 parts, 12 parts, 14 parts, 15 parts, etc., the weight parts of antioxidants can be 0.1 parts, 0.3 parts, 0.5 parts, 0.7 parts, 0.9 parts, 1 parts, etc., the weight parts of anti-UV agents can be 0.1 parts, 0.15 parts, 0.2 parts, 0.25 parts, 0.3 parts, etc., and the weight parts of active The weight parts of the charcoal powder can be 0.5 parts, 1 parts, 1.5 parts, 2 parts, 2.5 parts, etc., the weight parts of the filler can be 5 parts, 10 parts, 15 parts, 20 parts, 25 parts, etc., the weight parts of the lubricant can be 0.1 parts, 0.3 parts, 0.5 parts, 0.7 parts, 0.9 parts, 1 parts, etc., the weight parts of the flavoring substance can be 0.1 parts, 0.3 parts, 0.5 parts, 0.7 parts, 0.9 parts, 1 parts, etc., the weight parts of the polypropylene can be 10 parts, 20 parts, 40 parts, 60 parts, 70 parts, etc.

[0040] This application creatively adds high-porosity, high-activity functional activated carbon powder to the raw materials, adsorbs small molecules and odor substances in the materials, and adds a certain amount of fragrance substances to improve the smell of the materials while enhancing the odor perception, making it easier for recycled materials to be promoted and applied in interior materials, meeting the public's high requirements for the interior environment of automobiles. At the same time, this application obtains modified polyethylene by modifying polyethylene with monomers, and uses it as a compatibilizer in this system, which can improve the compatibility between polypropylene recycled materials and polypropylene, thereby reducing the impact of the addition of recycled materials on the performance of the prepared modified polypropylene, and meeting the requirements of automotive parts for material strength and stiffness. In addition, the selection of specific activated carbon powder and the use of the compatibilizer of this application can make the activated carbon powder well mixed in the raw materials, and have a positive effect on the strength of the material through dispersion, interface enhancement, molecular chain cross-linking, filling effect and stress dispersion. This effect not only improves the overall performance of the material, but also expands the application range of modified polypropylene; most importantly, the addition of activated carbon powder with a large adsorption value can effectively adsorb small molecular odor substances and effectively reduce the odor problem caused by recycled materials.

[0041] This application rationally designs the raw material composition of modified polypropylene, and realizes the recycling of resources and environmental protection by using a large amount of polypropylene recycled materials. By adding additives such as compatibilizers, antioxidants, and anti-UV agents, the overall performance and stability of the material are improved. By adding activated carbon powder, fillers, lubricants, and fragrance substances, the material is given a variety of additional functions, such as adsorption, decolorization, cost reduction, improved processing performance, and improved user experience.

[0042] In some embodiments, the recycled polypropylene material comes from one or more of recycled polypropylene for washing machine tubs, recycled polypropylene for instrument panels, and recycled polypropylene for door interior panels.

[0043] In some embodiments, the raw materials of the modified polyolefin include: polyolefin, monomer and initiator; wherein the weight of the monomer is 0.5% to 5% of the total weight of the modified polyolefin, and the weight of the initiator is 0.02% to 0.08% of the weight of the polyolefin.

[0044] In some embodiments, the polyolefin comprises one or more of ethylene propylene copolymer, polyethylene, polybutene, polypentene, polyoctene, propylene butene copolymer, ethylene butene copolymer and octene ethylene copolymer; and / or,

[0045] The monomers include: one or more of acrylate, maleic anhydride, acrylic acid, nadic anhydride and bismaleimide; and / or,

[0046] The initiator includes one or more of dicumyl peroxide, azobisisobutyronitrile and bis-2,5-hexane.

[0047] In some embodiments, the polyolefin is polyethylene and octene ethylene copolymer, and the weight ratio of the polyethylene to the octene ethylene is (1-5):1.

[0048] In some embodiments, the polyethylene is one or more of linear low-density polyethylene and high-density polyethylene; in some embodiments, it is linear low-density polyethylene.

[0049] In some embodiments, the linear low-density polyethylene has a melt index of 1.0 to 10.0 g / 10 min at 190° C. and a Vicat softening temperature of 80 to 110° C.

[0050] In some embodiments, the linear low density polyethylene has a melt index of 4.0 g / 10 min at 190°C and a Vicat softening temperature of 92°C.

[0051] In some embodiments, the octene ethylene copolymer has a melt index of 5 to 25 g / 10 min at 190° C. and a Mooney viscosity ML1+4 of 0.5 to 8 MU at 121° C.

[0052] In some embodiments, the octene ethylene copolymer has a melt index of 13 g / 10 min at 190° C. and a Mooney viscosity ML1+4 of 3 MU at 121° C.

[0053] The applicant creatively discovered that by modifying a specific polyethylene and octene ethylene copolymer with maleic anhydride monomer, the obtained compatibilizer is applied to the system, which can improve the compatibility of a specific recycled material PCR and polypropylene, thereby ensuring the performance of the prepared modified polypropylene. This may be because on the one hand, polyethylene and octene ethylene copolymers are both chain structures with good compatibility, and the ethylene segments without branches and the octene segments with long branches can jointly reduce the crystallinity of polypropylene and adjust the flexibility of the molecular chain, thereby improving the tensile strength, impact strength and other mechanical properties of the prepared modified polypropylene. On the other hand, a specific amount of maleic anhydride is selected to modify polyethylene and octene ethylene copolymers. Maleic anhydride is an unsaturated pentabasic anhydride with a high polar effect, thereby improving the activity of the copolymerization reaction. Moreover, the introduction of polar groups can enhance the compatibility between polypropylene and recycled material PCR, greatly improving the mechanical properties of the finally prepared modified polypropylene. Illustratively, the weight of the monomer is 0.5%, 1%, 1.5%, 2%, 2.5%, 3%, 3.5%, 4%, 4.5%, 5%, etc., of the total weight of the modified polyolefin, and the weight of the initiator is 0.02%, 0.03%, 0.04%, 0.05%, 0.06%, 0.07%, 0.08%, etc., of the weight of the polyolefin.

[0054] In some embodiments, the antioxidant includes: one or more of hydroxylamine antioxidants, thioether antioxidants, hindered phenol antioxidants and phosphite antioxidants.

[0055] In some embodiments, the antioxidant is a hindered phenol antioxidant and a phosphite antioxidant.

[0056] In some embodiments, the weight ratio of the hindered phenol antioxidant to the phosphite antioxidant is (1-2):1.

[0057] In some embodiments, the weight ratio of the hindered phenol antioxidant to the phosphite antioxidant is 3:2.

[0058] In some embodiments, the main components of the hindered phenol antioxidant include: one or more of tetrakis[β-(3,5-di-tert-butyl-4-hydroxyphenyl)propionate] pentaerythritol ester, β-(3,5-di-tert-butyl-4-hydroxyphenyl)propionate, 1,3,5-trimethyl, 2,4,6,-tris(3,5,-di-tert-butyl, 4-hydroxybenzyl)benzene, N,N'-bis-(3-(3,5-di-tert-butyl-4-hydroxyphenyl)propionyl)hexanediamine, and 1,3,5-tris(3,5-di-tert-butyl-4-hydroxybenzyl)isocyanuric acid; in some embodiments, it is tetrakis[β-(3,5-di-tert-butyl-4-hydroxyphenyl)propionate] pentaerythritol ester and β-(3,5-di-tert-butyl-4-hydroxyphenyl)propionate.

[0059] In some embodiments, the addition amount of the β-(3,5-di-tert-butyl-4-hydroxyphenyl) propionate is 1 wt % to 5 wt % of the hindered phenol antioxidant.

[0060] In some embodiments, the main components of the phosphite antioxidant include: one or more of bis(2,4-di-tert-butylphenyl)pentaerythritol diphosphite, tris(2,4-di-tert-butylphenyl)phosphite, and 2,2'-methylenebis(4,6-di-tert-butylphenyl)isooctyloxyphosphite.

[0061] In some embodiments, the phosphite antioxidant is tris(2,4-di-tert-butylphenyl) phosphite.

[0062] In some embodiments, the filler includes one or more of talc, calcium carbonate, barium sulfate, white carbon black, bentonite, attapulgite and starch.

[0063] In some embodiments, calcium carbonate and talc.

[0064] In some embodiments, the weight ratio of calcium carbonate to talc is 1:(0.5-2).

[0065] In some embodiments, the weight ratio of calcium carbonate to talc is 1:1.

[0066] In some embodiments, the activation degree of the calcium carbonate is ≥90%, and the average particle size is ≤10 μm.

[0067] In some embodiments, the activation degree of the calcium carbonate is ≥97%, and the average particle size is ≤2.5 μm.

[0068] In some embodiments, the talcum powder has a mesh size of 600-2000 mesh and a whiteness of ≥90%.

[0069] In some embodiments, the talc has a mesh size of 1250 mesh and a whiteness of ≥94%.

[0070] The applicant unexpectedly discovered that by selecting specific fillers, the dimensional stability of modified polypropylene can be increased while increasing the mechanical properties such as tensile strength and flexural strength. In addition, adding an appropriate amount of fillers can reduce production costs and have good economic benefits.

[0071] In some embodiments, the lubricant includes: one or more of a metal soap lubricant, a fatty acid amide lubricant, a hydrocarbon lubricant, and a siloxane lubricant.

[0072] In some embodiments, the lubricant is a metal soap lubricant, a fatty acid amide lubricant, and a hydrocarbon lubricant.

[0073] In some embodiments, the weight ratio of the metal soap lubricant, the fatty acid amide lubricant and the hydrocarbon lubricant is (1-8):(0.5-2):1.

[0074] In some embodiments, the weight ratio of the metal soap lubricant, the fatty acid amide lubricant, and the hydrocarbon lubricant is 4:1:1.

[0075] In some embodiments, the metal soap lubricant includes one or more of lead stearate, calcium stearate, magnesium stearate, and barium stearate;

[0076] In some embodiments, the metal soap lubricant is calcium stearate.

[0077] In some embodiments, the fatty acid amide lubricant includes one or more of oleamide, stearamide, erucamide, n-butyl stearate, and trihydroxystearate.

[0078] In some embodiments, the fatty acid amide lubricant is oleic acid amide.

[0079] In some embodiments, the solid content of the oleamide is 10 wt% to 30 wt%, and the surface tension at 25° C. is 15 mN / m to 35 mN / m.

[0080] In some embodiments, the solid content of the oleamide is 18 wt %, and the surface tension at 25° C. is 21-23 mN / m.

[0081] In some embodiments, the hydrocarbon lubricant includes one or more of polyethylene wax, microcrystalline wax, liquid paraffin, solid paraffin, and chlorinated paraffin.

[0082] In some embodiments, the hydrocarbon lubricant is polyethylene wax.

[0083] In some embodiments, the polyethylene wax has a softening point of 90 to 110° C. and a viscosity of 10 cps to 50 cps at 140° C.

[0084] In some embodiments, the polyethylene wax has a softening point of 95° C. and a viscosity of 10 cps to 20 cps at 140° C.

[0085] The applicant unexpectedly discovered that by selecting specific metal soap lubricants, fatty acid amide lubricants and hydrocarbon lubricants as lubricants, the three raw materials work synergistically to increase the melting rate of modified polypropylene without affecting its mechanical properties. This may be due to the good compatibility between the three specific lubricants and polypropylene and recycled material PCR, lubricating the inside and outside of the modified polypropylene at the same time, increasing the system compatibility while also increasing the melting rate of the modified polypropylene.

[0086] In some embodiments, the polypropylene includes: one or more of homopolymer polypropylene, random copolymer polypropylene, and impact copolymer polypropylene.

[0087] In some embodiments, the impact-resistant copolymer polypropylene has a melt index of 10 g / 10 min to 50 g / 10 min at 230° C., and an Izod notched impact strength of 30 to 60 KJ / m at 23° C. 2 , the tensile yield strength is 15~30MPa.

[0088] In some embodiments, the impact-resistant copolymer polypropylene has a melt index of 30 g / 10 min at 230° C. and an Izod notched impact strength of 46 KJ / m at 23° C. 2 , the tensile yield strength is 20.3MPa.

[0089] In some embodiments, the anti-UV agent includes one or more of stearic acid esters, fatty acid glycerides, and hexadecyl benzoate.

[0090] Anti-UV agent, full name is anti-ultraviolet agent, is a chemical additive that can absorb, reflect or scatter ultraviolet rays, thereby converting them into harmless energy. Anti-UV agent allows the material to be applied to plastic parts of instrument panels, sub-instrument panels, and door guard assembly, without coating, to meet the light aging requirements of interior parts.

[0091] The aroma substance includes: n-butyl acetate.

[0092] The addition of n-butyl acetate can improve the compatibility of PP, PCR and activated carbon. At the same time, n-butyl acetate will emit a fruity aroma. After being partially physically adsorbed by activated carbon, it will continue to emit a fruity aroma.

[0093] In some embodiments, the iodine adsorption value of the activated carbon powder is greater than 1200 mg / g, and the mesh size of the activated carbon powder is less than 200 meshes.

[0094] The addition of activated carbon powder with a large adsorption value can effectively adsorb small molecular odor substances and effectively reduce the odor problem caused by the recycled materials. For example, the iodine adsorption value of the activated carbon powder can be 1300 mg / g, 1350 mg / g, 1400 mg / g, 1450 mg / g, 1500 mg / g, etc., and the mesh size of the activated carbon powder can be 100 mesh, 120 mesh, 140 mesh, 160 mesh, 180 mesh, 190 mesh, etc.

[0095] In some embodiments, the modified polypropylene satisfies at least one of the following properties:

[0096] Tensile strength ≥18.5MPa;

[0097] Flexural modulus ≥1890MPa;

[0098] Izod beam notched impact strength ≥40kJ / m 2 ;

[0099] Melt index ≥26.5g / 10min;

[0100] Odor intensity ≤ level 3.5.

[0101] Tensile strength is the maximum stress that a material can withstand during stretching; flexural modulus is a physical quantity that measures the material's ability to resist deformation when bent; Izod notched impact strength is a physical quantity that measures the material's ability to resist damage when impacted; melt index is a physical quantity that measures the material's fluidity and is closely related to the material's processing properties. Polypropylene with a high melt index has better fluidity and processing properties; odor intensity is a physical quantity that measures the degree of odor released by a material. For applications that require contact with food, medicine, or human skin, modified polypropylene with low odor intensity is a safer choice.

[0102] Figure 1 A schematic flow chart of a method for preparing modified polypropylene provided in an embodiment of the present application.

[0103] See also Figure 1 The present application provides a method for preparing the modified polypropylene as described in any one of the above embodiments, the method comprising:

[0104] S1. Mixing polypropylene recycled material, modified polyolefin, antioxidant, UV inhibitor, chemically activated carbon powder, filler, lubricant, fragrance material and polypropylene according to weight parts to obtain a mixture;

[0105] S2. Melt-extrude and granulate the mixture to obtain the modified polypropylene; the temperature of the melt-extrusion is 180° C. to 250° C., and the rotation speed of the melt-extrusion is 100 rad / min to 300 rad / min.

[0106] In some embodiments, the method for preparing the activated carbon powder comprises:

[0107] The carbon material is immersed in a strong alkali or oxidant solution and then dried to obtain a precursor;

[0108] The precursor is heat-treated to obtain activated carbon powder; the heat treatment temperature is 600° C. to 900° C., and the heat treatment time is 2 h to 3 h.

[0109] Specifically, the preparation method of activated carbon powder is as follows: select high-quality carbon materials, such as coconut shell and wood activated carbon, which have a high surface area and good pore structure. Chemical reagents such as sodium hydroxide or potassium hydroxide are selected to increase the surface alkalinity and pore structure. Oxidants such as hydrogen peroxide or nitric acid are selected for surface oxidation and functionalization. Soak the selected carbon material in a chemical reagent solution for several hours and then dry it to remove moisture. Heat treatment is performed at a temperature of 600 to 900°C in an inert gas (such as nitrogen) environment for 2 to 3 hours. This process promotes the reaction of the activator with the carbon material to form a rich pore structure. Wash the activated material to remove residual chemical reagents, and after drying again, crush the activated carbon into particles less than 200 mesh. Chemical activation increases the number of micropores and mesopores, and improves the specific surface area; improves the adsorption and oxidation properties of polar gases or acidic gases (sulfur dioxide, hydrogen sulfide, etc.) (strong oxidizing properties can oxidize formaldehyde, benzene series, etc.); the iodine adsorption value is greater than 1200 mg / g, and has a strong adsorption capacity for small molecular organic matter. Through the above treatment, activated carbon powder can effectively improve the VOC adsorption capacity of plastic particles and improve other physical and chemical properties of the material. Exemplarily, the heat treatment temperature can be 600°C, 650°C, 700°C, 750°C, 800°C, 850°C, 900°C, etc., and the heat treatment time can be 2h, 2.2h, 2.4h, 2.6h, 2.8h, 3h, etc.

[0110] In some embodiments, the preparation method of the compatibilizer comprises:

[0111] The polyolefin, monomer and initiator are mixed, and then added into a twin-screw for extrusion granulation to obtain the compatibilizer; the extrusion temperature is 170° C. to 250° C., and the screw speed is 350 rad / min to 550 rad / min.

[0112] The product prepared by the preparation method of the modified polypropylene is the modified polypropylene mentioned above. The chemical composition and structure of the modified polypropylene prepared by the preparation method of the modified polypropylene can refer to the above embodiment. Since the preparation method of the modified polypropylene adopts part or all of the technical solutions of the modified polypropylene embodiment, it at least has all the beneficial effects brought by the technical solutions of the modified polypropylene embodiment, which will not be described one by one here.

[0113] The present application will be further described below in conjunction with specific embodiments. It should be understood that these embodiments are intended only to illustrate the present application and are not intended to limit the scope of the present application. The experimental methods for which specific conditions are not specified in the following examples are usually measured according to industry standards. If there is no corresponding industry standard, then the conditions recommended by the manufacturer are followed.

[0114] Example 1

[0115] Example 1 provides a low-odor modified polypropylene containing recycled material PCR. The raw materials of the modified polypropylene containing recycled material PCR include, by weight: 10 parts of recycled polypropylene, 10 parts of compatibilizer, 0.5 parts of antioxidant, 0.25 parts of anti-UV agent, 1.5 parts of activated carbon powder, 0.1 parts of flavoring substance, 20 parts of filler, 0.5 parts of lubricant, and the remainder of polypropylene is supplemented to 100 parts.

[0116] The polypropylene recycled material comes from recycled polypropylene used in washing machine barrels.

[0117] The compatibilizer is modified polyolefin.

[0118] The preparation method of the modified polyolefin is as follows: after mixing polyolefin, monomer and initiator, adding the mixture into a twin-screw for extrusion granulation, the extrusion temperature is 200° C., and the screw speed is 450 r / min.

[0119] The polyolefin is polyethylene and octene ethylene copolymer.

[0120] The weight ratio of the polyethylene to the octene ethylene copolymer is 3:1.

[0121] The polyethylene is linear low density polyethylene.

[0122] The linear low-density polyethylene has a melt index of 4.0 g / 10 min at 190° C. and a Vicat softening temperature of 92° C.

[0123] The octene-ethylene copolymer has a melt index of 13 g / 10 min at 190° C. and a Mooney viscosity ML1+4 of 3 MU at 121° C.

[0124] The monomer is maleic anhydride.

[0125] The weight of the monomer is 3% of the weight of the modified polyolefin.

[0126] The initiator is bis-2,5-hexane.

[0127] The weight of the initiator is 0.05% of the weight of the polyolefin.

[0128] The extrusion temperature is 200° C. and the screw speed is 450 r / min.

[0129] The antioxidants are hindered phenol antioxidants and phosphite antioxidants.

[0130] The weight ratio of the hindered phenol antioxidant to the phosphite antioxidant is 3:2.

[0131] The hindered phenol antioxidant consists of a hindered phenol antioxidant whose main component is pentaerythritol tetrakis[β-(3,5-di-tert-butyl-4-hydroxyphenyl)propionate and a hindered phenol antioxidant whose main component is n-octadecylβ-(3,5-di-tert-butyl-4-hydroxyphenyl)propionate.

[0132] The added amount of the hindered phenol antioxidant whose main component is n-octadecyl β-(3,5-di-tert-butyl-4-hydroxyphenyl) propionate is 3wt% of the hindered phenol antioxidant.

[0133] The main component of the phosphite antioxidant is tris(2,4-di-tert-butylphenyl) phosphite.

[0134] The fillers are calcium carbonate and talc.

[0135] The weight ratio of the calcium carbonate to talc is 1:1.

[0136] The activation degree of the calcium carbonate is ≥97%, and the average particle size is ≤2.5 μm.

[0137] The mesh number of the talcum powder is 1250 meshes, and the whiteness is ≥94%.

[0138] The lubricant is a metal soap lubricant, a fatty acid amide lubricant and a hydrocarbon lubricant.

[0139] The weight ratio of the metal soap lubricant, the fatty acid amide lubricant and the hydrocarbon lubricant is 4:1:1.

[0140] The metal soap lubricant is calcium stearate.

[0141] The fatty acid amide lubricant is oleic acid amide.

[0142] The solid content of the oleic acid amide is 18 wt %, and the surface tension at 25° C. is 21-23 mN / m.

[0143] The hydrocarbon lubricant is polyethylene wax.

[0144] The polyethylene wax has a softening point of 95° C. and a viscosity of 10 to 20 cps at 140° C.

[0145] The polypropylene is impact-resistant copolymer polypropylene.

[0146] The impact-resistant copolymer polypropylene has a melt index of 30 g / 10 min at 230° C., an Izod notched impact strength of 46 KJ / m 2 at 23° C., and a tensile yield strength of 20.3 MPa.

[0147] The aroma substance is n-butyl acetate.

[0148] The preparation method of the activated carbon powder is as follows: the carbon material is immersed in a sodium hydroxide solution, and then dried after immersion for 10 hours to remove moisture; heat treatment is performed at a temperature of 700°C in a nitrogen environment for 3 hours; the activated material is washed to remove residual chemical reagents, and after drying again, the activated carbon is crushed into particles less than 200 mesh. The iodine adsorption value of the activated carbon powder is 1300 mg / g, and the mesh size of the activated carbon powder is 100 mesh.

[0149] Example 1 also provides a method for preparing low-odor modified polypropylene containing recycled material PCR, comprising the following steps:

[0150] The raw materials are mixed uniformly by weight, extruded by a screw extruder, cooled by water after extrusion, and pelletized to obtain the product. The temperature of the screw extruder is 220° C., and the speed is 200 rad / min.

[0151] Example 2

[0152] Example 2 provides a low-odor modified polypropylene containing recycled material PCR, and the specific implementation method is the same as that of Example 1, except that:

[0153] In parts by weight, the raw materials of the modified polypropylene containing recycled material PCR include: 20 parts of recycled polypropylene, 10 parts of compatibilizer, 0.5 parts of antioxidant, 0.25 parts of anti-UV agent, 1.5 parts of activated carbon powder, 0.1 parts of flavoring substance, 20 parts of filler, 0.5 parts of lubricant, and the remainder of polypropylene is supplemented to 100 parts.

[0154] Example 3

[0155] Example 3 provides a low-odor modified polypropylene containing recycled material PCR, and the specific implementation method is the same as that of Example 1, except that:

[0156] In parts by weight, the raw materials of the modified polypropylene containing recycled material PCR include: 30 parts of recycled polypropylene, 10 parts of compatibilizer, 0.5 parts of antioxidant, 0.25 parts of anti-UV agent, 1.5 parts of activated carbon powder, 0.1 parts of flavoring substance, 20 parts of filler, 0.5 parts of lubricant, and the remainder of polypropylene is supplemented to 100 parts.

[0157] Example 4

[0158] Example 4 provides a low-odor modified polypropylene containing recycled material PCR, and the specific implementation method is the same as that of Example 1, except that:

[0159] In parts by weight, the raw materials of the modified polypropylene containing recycled material PCR include: 40 parts of polypropylene recycled material, 10 parts of compatibilizer, 0.5 parts of antioxidant, 0.25 parts of anti-UV agent, 2.5 parts of activated carbon powder, 0.1 parts of flavoring substance, 20 parts of filler, 0.5 parts of lubricant, and the remainder of polypropylene is supplemented to 100 parts.

[0160] Example 5

[0161] Example 5 provides a low-odor modified polypropylene containing recycled material PCR, and the specific implementation method is the same as that of Example 1, except that:

[0162] In parts by weight, the raw materials of the modified polypropylene containing recycled material PCR include: 50 parts of recycled polypropylene, 10 parts of compatibilizer, 0.5 parts of antioxidant, 0.25 parts of anti-UV agent, 2.5 parts of activated carbon powder, 0.1 parts of flavoring substance, 20 parts of filler, 0.5 parts of lubricant, and the remainder of polypropylene is supplemented to 100 parts.

[0163] Comparative Example 1

[0164] Comparative Example 1 provides a low-odor modified polypropylene containing recycled material PCR, and the specific implementation method is the same as that of Example 1, except that:

[0165] The polyolefin is polyethylene.

[0166] The polyethylene is linear low density polyethylene.

[0167] The linear low-density polyethylene has a melt index of 4.0 g / 10 min at 190° C. and a Vicat softening temperature of 92° C.

[0168] No activated carbon powder and fragrance added.

[0169] Comparative Example 2

[0170] Comparative Example 2 provides a low-odor modified polypropylene containing recycled material PCR, and the specific implementation method is the same as that of Example 1, except that:

[0171] The carbon powder is wood activated carbon that has not been chemically treated. The iodine adsorption value of wood activated carbon is 600 mg / g, and the sieve size is 100 mesh.

[0172] Comparative Example 3

[0173] Comparative Example 3 provides a low-odor modified polypropylene containing recycled material PCR, and the specific implementation method is the same as that of Example 1, except that:

[0174] No activated carbon powder added.

[0175] Comparative Example 4

[0176] Comparative Example 1 provides a low-odor modified polypropylene containing recycled material PCR, and the specific implementation method is the same as that of Example 1, except that:

[0177] No fragrance added.

[0178] Comparative Example 5

[0179] Comparative Example 5 provides a low-odor modified polypropylene containing recycled material PCR, and the specific implementation method is the same as that of Example 1, except that:

[0180] No polyolefin modification and no fragrance added.

[0181] Comparative Example 6

[0182] Comparative Example 6 provides a low-odor modified polypropylene containing recycled material PCR, and the specific implementation method is the same as that of Example 1, except that:

[0183] The polyolefin is not modified and no activated carbon powder is added.

[0184] The modified polypropylene obtained in Examples 1 to 5 and Comparative Examples 1 to 6 was subjected to performance measurement, and the results are shown in Table 1. The performance measurement method is as follows:

[0185] 1. Tensile strength

[0186] The modified polypropylenes prepared in Examples 1 to 5 and Comparative Examples 1 to 6 were tested for tensile strength at a test speed of 50 mm / min with reference to the method described in GB / T 1040.1. The results are recorded in Table 1.

[0187] 2. Flexural modulus

[0188] The modified polypropylene prepared in Examples 1 to 5 and Comparative Examples 1 to 6 was tested for its flexural modulus with reference to GB / T 9341, with a strip size of 80 mm×10 mm×(4.0±0.2) mm, a test speed of 2 mm / min, and a support span of 64 mm. The results are recorded in Table 1.

[0189] 3. Impact resistance

[0190] The modified polypropylene prepared in Examples 1 to 5 and Comparative Examples 1 to 6 was tested for its Izod notched impact strength with reference to GB / T 1843, with a strip size of 80 mm×10 mm×(4.0±0.2) mm, A-type notch, and a temperature of 23° C. The results are recorded in Table 1.

[0191] 4. Melt index

[0192] For the modified polypropylenes prepared in Examples 1 to 5 and Comparative Examples 1 to 6, refer to GB / T 3682.1-2018, Method A (mass measurement method), the test conditions are: 230°C / 2.16KG, and the melt index is tested. The results are recorded in Table 1.

[0193] 5. Odor evaluation

[0194] For the modified polypropylene prepared in Examples 1 to 5 and Comparative Examples 1 to 6, refer to the odor evaluation method of VDA270, use a 1L odor evaluation bottle, add equal amounts of materials, place in an oven at 80°C for 2 hours, take out and cool to room temperature, and five odor evaluators evaluate the odor, and take the average value as the odor average result. The odor average adopts a 6-level system, with level 1 being the best and level 6 being the worst. The odor level currently accepted by automobile OEMs is ≤ level 3.5.

[0195] Table 1 Properties of modified polypropylene prepared in Examples 1 to 5 and Comparative Examples 1 to 6

[0196]

[0197] As shown in Table 1, the tensile strength of the modified polypropylene of Examples 1 to 5 is ≥18.5MPa; the flexural modulus is ≥1890MPa; and the Izod notched impact strength is ≥40kJ / m 2 ; Melt index ≥ 26.5g / 10min; Odor intensity ≤ 3.5 level; In comparative example 1, the polyolefin is polyethylene, the compatibility of new materials and recycled materials is lower than that of Example 1, and the mechanical properties are lowered; No activated carbon powder and fragrance substances are added, and the odor of the modified polypropylene is poor; In comparative example 2, the carbon powder is wood activated carbon that has not been chemically treated, and it cannot effectively adsorb small molecular odor substances; In comparative example 3, no activated carbon powder is added, and it cannot effectively adsorb small molecular odor substances, and the synergistic effect of activated carbon powder and modified polyolefin is lacking, and the mechanical properties of modified polypropylene are reduced; In comparative example 4, no fragrance substances are added, and the odor of modified polypropylene is poor; In comparative example 5, the polyolefin is not modified, and the compatibility of new materials and recycled materials is lower than that of Example 1, and the mechanical properties are reduced. In comparative example 6, the polyolefin is not modified, no activated carbon powder is added, and the synergistic effect of activated carbon powder and modified polyolefin is lacking, and the mechanical properties of modified polypropylene are seriously reduced.

[0198] In addition, one or more technical solutions in the embodiments of the present application have at least the following technical effects or advantages:

[0199] In the embodiments of the present application, a modified polyolefin is obtained by modifying a polyolefin with a monomer, and the modified polyolefin is used as a compatibilizer in the present system, thereby improving the compatibility between the polypropylene recycled material and the polypropylene, thereby reducing the influence of the addition of the recycled material on the performance of the prepared modified polypropylene, and increasing the amount of the polypropylene recycled material added to the modified polypropylene, saving costs, and ensuring the mechanical properties of the modified polypropylene.

[0200] In the embodiment of the present application, by adding high-performance activated carbon powder, the odor of the recycled material is reduced, the requirements for the use of interior materials are met, and the recycled material can be used for interior parts.

[0201] In the embodiment of the present application, by adding the aromatic substance n-butyl acetate, the recycled material continues to emit a fruity aroma, which fundamentally solves the odor problem of the recycled material and has broad application prospects in interior materials.

[0202] In the embodiments of the present application, recycled materials are used and creatively applied to interior parts, while achieving a relatively good interior odor VOC effect. The application of recycled materials can reduce material carbon emissions by 85% to 90%, with significant carbon reduction effects, and has a significant effect on the country's green and low-carbon strategy.

[0203] The above description is only a specific implementation of the present application, so that those skilled in the art can understand or implement the present application. Various modifications to these embodiments will be apparent to those skilled in the art, and the general principles defined herein can be implemented in other embodiments without departing from the spirit or scope of the present application. Therefore, the present application will not be limited to the embodiments shown herein, but will conform to the widest scope consistent with the principles and novel features applied for herein.

Claims

1. A modified polypropylene containing recycled material PCR, wherein the raw materials of the modified polypropylene include, by weight: Polypropylene recycled material>0 parts and ≤50 parts, modified polyolefin 5 parts to 15 parts, chemically activated carbon powder 0.5 parts to 2.5 parts, filler 5 parts to 25 parts, flavoring material 0.1 parts to 1 parts and polypropylene 10 parts to 70 parts.

2. The modified polypropylene according to claim 1, characterized in that The iodine adsorption value of the chemically activated carbon powder is greater than 1200 mg / g, and the mesh size of the chemically activated carbon powder is less than 200 meshes.

3. The modified polypropylene according to claim 1, characterized in that The raw materials of the modified polyolefin include: polyolefin, monomer and initiator; wherein the weight of the monomer is 0.5% to 5% of the total weight of the modified polyolefin, and the weight of the initiator is 0.02% to 0.08% of the weight of the polyolefin.

4. The modified polypropylene according to claim 3, characterized in that The polyolefin comprises one or more of ethylene-propylene copolymer, polyethylene, polybutene, polypentene, polyoctene, propylene-butene copolymer, ethylene-butene copolymer and octene-ethylene copolymer; and / or, The monomers include: one or more of acrylate, maleic anhydride, acrylic acid, nadic anhydride and bismaleimide; and / or, The initiator includes one or more of dicumyl peroxide, azobisisobutyronitrile and bis-2,5-hexane.

5. The modified polypropylene according to claim 4, characterized in that The polyolefin is polyethylene and octene-ethylene copolymer, and the weight ratio of the polyethylene to the octene-ethylene is (1-5):

1.

6. The modified polypropylene according to claim 1, characterized in that The filler comprises: one or more of talc, calcium carbonate, barium sulfate, white carbon black, bentonite, attapulgite and starch; and / or, The polypropylene includes: one or more of homopolymer polypropylene, random copolymer polypropylene and impact copolymer polypropylene; and / or, The aroma substance includes: n-butyl acetate.

7. The modified polypropylene according to claim 1, characterized in that In parts by weight, the raw materials of the modified polypropylene further include: 0.1 to 1 part of antioxidant, 0.1 to 0.3 part of anti-UV agent and 0.1 to 1 part of lubricant.

8. The modified polypropylene according to claim 1, characterized in that The modified polypropylene satisfies at least one of the following properties: Tensile strength ≥18.5MPa; Flexural modulus ≥1890MPa; Izod beam notched impact strength ≥40kJ / m 2 ; Melt index ≥26.5g / 10min; Odor intensity ≤ level 3.

5.

9. A method for preparing modified polypropylene according to any one of claims 1 to 8, characterized in that: The method comprises: The polypropylene recycled material, modified polyolefin, antioxidant, UV inhibitor, chemically activated carbon powder, filler, lubricant, fragrance material and polypropylene are mixed according to weight parts to obtain a mixed material; The mixed material is melt-extruded and granulated to obtain the modified polypropylene; the temperature of the melt-extrusion is 180° C. to 250° C., and the rotation speed of the melt-extrusion is 100 rad / min to 300 rad / min.

10. The method according to claim 9, characterized in that The preparation method of the activated carbon powder comprises: The carbon material is immersed in a strong alkali or oxidant solution and then dried to obtain a precursor; The precursor is heat-treated to obtain activated carbon powder; the heat treatment temperature is 600° C. to 900° C., and the heat treatment time is 2 h to 3 h.

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