Low-odor thermoplastic vulcanized rubber for automobile skin as well as preparation method and application of low-odor thermoplastic vulcanized rubber

Abstract

The invention discloses low-odor thermoplastic vulcanized rubber for an automobile skin as well as a preparation method and application of the low-odor thermoplastic vulcanized rubber. The raw materials comprise 50 to 80 parts of ethylene-propylene-diene copolymer rubber, 20 to 50 parts of polypropylene, 5 to 15 parts of a compatilizer, 0.5 to 2.5 parts of a compound cross-linking agent, 0.5 to 2.0 parts of an odor adsorbent and 0.5 to 1.0 part of an antioxidant. The preparation method comprises the following steps: banburying and blending, dynamically vulcanizing by using a first double-screw extruder, adsorbing and deeply devolatilizing by using a second double-screw extruder, and carrying out vacuum baking at 100 DEG C. By utilizing the synergistic effect of the cross-linking agent and the assistant cross-linking agent, the degradation of polypropylene is inhibited while the cross-linking efficiency is ensured, and a low-boiling-point reaction by-product (tert-butyl alcohol) is thoroughly removed through a multi-stage devolatilization process, so that the problems that the traditional TPV material is strong in odor and easy to atomize are solved. The smell grade of the obtained material is less than or equal to 3.0 grade, and the atomization value is lt; and the coating is suitable for high-end automotive trim skins.

Description

TECHNICAL FIELD

[0001] The present application relates to the field of polymer material science and automotive interior material technology, and particularly relates to a low-odor thermoplastic vulcanized rubber for automotive skin and a preparation method and application thereof. BACKGROUND

[0002] In the modern automotive manufacturing industry, with the increasing demand of consumers for the health and comfort of the cabin, the air quality in the car has become one of the core indicators for evaluating the quality of the car. The automotive skin, as the surface covering material of the instrument panel, door panel, center console and other interior parts, has the characteristics of large surface area, direct exposure to light and high temperature environment, and is one of the main potential sources of volatile organic compounds and odor in the car. Thermoplastic vulcanized rubber, especially dynamic vulcanized elastomer based on polypropylene and ethylene-propylene-diene copolymer rubber, has gradually replaced traditional polyvinyl chloride and expensive polyurethane, and become the preferred material for light weight and environmental protection of automotive interior, because it has high elasticity of vulcanized rubber and easy processability, low density and recyclability of thermoplastic.

[0003] However, the existing commercial TPV materials still face great challenges in meeting the stringent low-odor and low-fogging standards of high-end OEMs. The main technical bottleneck is due to the inherent chemical composition of the material and the defects of the preparation process:

[0004] Firstly, the problem of irritating odor caused by crosslinking system. The most mature process for preparing TPV in industry is dynamic vulcanization, that is, chemical crosslinking of rubber phase occurs during plastic melt blending. Peroxydicumyl is generally used as an initiator in traditional process. DCP will inevitably undergo β-scission side reaction to generate acetophenone during high-temperature decomposition to initiate crosslinking reaction. Acetophenone has a very typical and unpleasant "bitter almond" or irritating sweet taste. More troublesome is that its boiling point is as high as 202℃, much higher than the conventional post-processing temperature of TPV, and it is very difficult to completely remove by conventional extrusion vacuum devolatilization. This means that the acetophenone generated by the reaction is almost permanently retained in the product, resulting in that the odor level of traditional TPV can only reach 4.0, which is difficult to meet the needs of high-end applications.

[0005] Secondly, the degradation odor problem of polypropylene matrix. In the process of dynamic vulcanization initiated by peroxide, free radicals not only initiate EPDM crosslinking, but also attack the tertiary carbon hydrogen atoms on the PP backbone, causing β-scission degradation of PP. This degradation not only reduces the mechanical properties of the material, but also generates a series of low molecular weight aldehydes, ketones and acids, which are important reasons for the generation of acid smell or burnt smell of the material.

[0006] In addition, the residual removal efficiency in the process is low. Traditional TPV preparation usually adopts a "one-step" twin-screw extrusion process, that is, all mixing, shearing, reaction and devolatilization are completed in one extruder. Due to the short distance between the reaction section and the devolatilization section, and the high melt viscosity, volatile small molecules wrapped inside or deep in the rubber particles are difficult to diffuse to the melt surface to be removed by vacuum in a short time. Although some technologies try to introduce adsorbents or masking agents, these methods often treat the symptoms but not the root cause, and the adsorbents are easy to be inactivated or saturated at high temperature and high shear.

[0007] In the face of these challenges, developing a new TPV technology that can not only maintain excellent physical and mechanical properties, but also completely eliminate odor sources from both chemical reaction sources and physical preparation processes, has become a key problem that needs to be solved in the current industry. SUMMARY

[0008] The purpose of the present application is to provide a low-odor thermoplastic vulcanized rubber for automobile skin and its preparation method and application.

[0009] To achieve the above purpose, the technical scheme adopted by the present application is:

[0010] A low-odor thermoplastic vulcanized rubber for automobile skin, the raw materials of which include the following components in parts by weight:

[0011] Ethylene-propylene-diene copolymer rubber (EPDM) 50~80 parts,

[0012] Polypropylene resin (PP) 20~50 parts,

[0013] Compatibility agent 5~15 parts,

[0014] Compound crosslinking agent 0.5~2.5 parts,

[0015] Odor adsorbent 0.5~2.0 parts,

[0016] Antioxidant 0.5~1.0 parts.

[0017] In the above scheme, EPDM, PP and compound crosslinking agent are the core reaction components. EPDM as the dispersed phase gives the material excellent elasticity and soft touch; PP as the continuous phase provides the material with heat-resistant skeleton and processing fluidity. Compound crosslinking agent is the key to realize dynamic vulcanization process and control the odor level of the material.

[0018] Further technical solutions, the ethylene-propylene-diene copolymer rubber is a semi-crystalline EPDM rubber, the ethylene content is 65%~75%, the third monomer ethylidene norbornene content is 4.0%~5.5%, and the Mooney viscosity under the condition of ML(1+4)125℃ is 20~25MU.

[0019] Further, the polypropylene resin is a high flow impact copolymer polypropylene with a density of 0.90-0.91 g / cm 3 , a melt mass flow rate of 15-35 g / 10 min at 230℃ / 2.16 kg, and a flexural modulus of 900-1300 MPa. The high flow PP is beneficial to form a continuous phase during dynamic vulcanization, which encapsulates the crosslinked rubber particles.

[0020] The compatibilizer is selected from one or a mixture of both of styrene-ethylene-butylene-styrene block copolymer and ethylene-octene copolymer, which as an interfacial modifier, can reduce the interfacial tension between the rubber and plastic phases, improve compatibility, and make the rubber particles smaller and more uniform in size.

[0021] Further, the complex crosslinking agent is composed of a main crosslinking agent and a co-crosslinking agent in a mass ratio of 2:1 to 4:1; the main crosslinking agent is bis(tert-butyl peroxyisopropyl) benzene (BIBP) with a purity of ≥96%; and the co-crosslinking agent is trimethylolpropane trimethacrylate (TMPTMA). The thermal decomposition products of BIBP mainly include tert-butyl alcohol and diisopropyl benzene, and do not produce benzaldehyde with a bitter almond taste. The boiling point of tert-butyl alcohol is about 82℃, which makes it easy to be gasified and removed in subsequent extrusion vacuum devolatilization and 100℃ vacuum baking processes. At the same time, the trifunctional co-crosslinking agent TMPTMA has a dual role: 1. Synergistic crosslinking: the three high-activity methacrylate double bonds in the TMPTMA molecule can quickly react with the free radicals produced by the decomposition of peroxide and graft onto the EPDM molecular chain, promoting the formation of a dense crosslinking network and improving the crosslinking efficiency. 2. Degradation inhibition: TMPTMA as a high-efficiency free radical trapping agent has a significantly higher reaction rate with free radicals than the β-chain scission degradation rate of polypropylene. By preferentially binding with free radicals, it can competitively protect the polypropylene molecular chain, thereby significantly reducing the small molecular odor substances produced by polypropylene degradation.

[0022] Further, the odor adsorbent is selected from one or a mixture of several of modified zeolite molecular sieve, mesoporous silica, and zinc castor oil acid master batch, with a pore size distribution of 0.5-2.0 nm.

[0023] Further technical solutions, the antioxidant is selected from one or a mixture of several of tetrakis [β-(3,5-di-tert-butyl-4-hydroxyphenyl) propionic acid] pentaerythritol ester (antioxidant 1010), tris [2,4-di-tert-butylphenyl] phosphite (antioxidant 168), β-(3,5-di-tert-butyl-4-hydroxyphenyl) propionic acid n-octadecyl ester (antioxidant 1076). Preferably, a mixture of tris [2,4-di-tert-butylphenyl] phosphite (antioxidant 168) and tetrakis [β-(3,5-di-tert-butyl-4-hydroxyphenyl) propionic acid] pentaerythritol ester (antioxidant 1010).

[0024] Further, the application also discloses a preparation method of the low-odor thermoplastic vulcanized rubber for automobile skin.

[0025] Step one, in a mixer, ethylene-propylene-diene copolymer rubber and polypropylene resin, compatibilizer and antioxidant are added according to the formula proportion, and mixing is carried out at 160-190 DEG C for 5-10 minutes, and the rotating speed is 40-80 rpm, so as to form a blending melt;

[0026] Step two, the blending melt is fed into a first double-screw extruder, and a compounded crosslinking agent is injected, and dynamic vulcanization is carried out under the conditions of 180-220 DEG C and 300-500 rpm and strong shearing, and volatile components are removed through a first vacuum exhaust port, and intermediate particles are obtained through extrusion and granulation;

[0027] Step three, the intermediate particles are mixed with an odor adsorbent, and then fed into a second double-screw extruder, and melting dispersion and adsorption treatment are carried out at 170-200 DEG C, and deep devolatilization is carried out through a second vacuum exhaust port, and then extrusion and granulation are carried out;

[0028] Step four, the particles obtained in step three are placed in a vacuum oven, and baking is carried out at 90-110 DEG C under vacuum for 1-2 hours, so as to obtain the low-odor thermoplastic vulcanized rubber for automobile skin.

[0029] Further technical solutions, the temperature of the first double-screw extruder in step two is set as follows: the feeding section is 140-160 DEG C, the compression melting section is 170-190 DEG C, the reaction vulcanization section is 190-210 DEG C, the vacuum devolatilization section is 180-200 DEG C, and the head is 170-190 DEG C; and the rotating speed of the main screw is 300-600 rpm.

[0030] Further technical solutions, the vacuum devolatilization system needs to be opened in the extrusion processes in steps two and three, and the vacuum degree is controlled to be-0.08 to-0.1 MPa; and in step two, a synergistic crosslinking reaction occurs.

[0031] Firstly, the main crosslinking agent bis(tert-butyl peroxy isopropyl) benzene decomposes under heating condition to generate tert-butyl alcohol and active radicals;

[0032] Subsequently, the auxiliary crosslinking agent trimethylolpropane trimethacrylate preferentially captures the radicals and connects to the molecular chains of the ethylene-propylene-diene copolymer rubber through grafting reaction;

[0033] Finally, under the action of shear field, the ethylene-propylene-diene copolymer rubber phase is crosslinked and phase inversion is realized; the by-product tert-butyl alcohol is removed in the subsequent vacuum heat treatment process.

[0034] Further, in step four, since the boiling point of the decomposition product tert-butyl alcohol of BIBP is 82 DEG C, and the baking temperature is set to 100 DEG C, the residual tert-butyl alcohol is in a superheated state by using the thermodynamic principle, and is completely'steamed' out from the inside of the particles in combination with the negative pressure provided by high vacuum, so that the low odor requirement is realized.

[0035] Further, the application further discloses an application of the low-odor thermoplastic vulcanized rubber for automobile skin, and the low-odor thermoplastic vulcanized rubber is used to prepare interior trim products including automobile instrument panel skin, door panel cover and central passage cover through injection molding, extrusion or calendering process, and no oil mist is generated at 80 DEG C to 120 DEG C high temperature and light.

[0036] As used herein, the terms "comprise", "comprising", "include", "including", "have", "having" and the like are open-ended terms that are intended to mean including, but not limited to.

[0037] As used herein, the terms "comprise", "comprising", "include", "including", "have", "having" and the like are open-ended terms that are intended to mean including, but not limited to.

[0038] The working principle and advantages of the application are as follows:

[0039] The application provides a low-odor thermoplastic vulcanized rubber for automobile skin and a preparation method and application thereof, and through the synergistic effect of chemical formula and physical process, the odor problem of the TPV material is systematically solved.

[0040] At the chemical level, the application uses the main crosslinking agent BIBP to replace the traditional DCP, and the thermal decomposition product is mainly tert-butyl alcohol (boiling point about 82℃) and diisopropylbenzene, which eliminates the generation of acetophenone (boiling point 202℃) with bitter almond smell from the reaction source. At the same time, the trifunctional auxiliary crosslinking agent TMPTMA is introduced, which uses multiple high-activity double bonds to preferentially capture free radicals and graft to the EPDM molecular chain, not only improving the crosslinking efficiency, but more importantly, effectively inhibiting the β-scission attack of free radicals on the PP main chain through competitive reaction, thereby greatly reducing the acid smell of small molecule odor substances generated by PP degradation.

[0041] At the physical process level, the application designs a unique "two-step extrusion + vacuum baking" process. The first step of extrusion mainly realizes dynamic vulcanization reaction; the second step of extrusion is specially used to introduce adsorbent and provide a new melt surface for secondary efficient devolatilization, avoiding the premature failure of adsorbent in the high-temperature and high-shear reaction section. Finally, through the 100℃ vacuum baking step, using the thermodynamic condition that the boiling point of tert-butyl alcohol (82℃) is lower than the baking temperature, combined with vacuum negative pressure, the deep residual volatile substances are completely removed.

[0042] The application makes the obtained TPV material maintain excellent mechanical properties while the odor level is stable to reach ≤3.0 level and the atomization value is lower than 0.5mg, fully meeting the strict standards of high-end automotive interior. DETAILED DESCRIPTION

[0043] The following will be described in detail to clearly explain the present case, and any person skilled in the art can modify and modify the technology taught by the present case after understanding the embodiments of the present case, without departing from the spirit and scope of the present case.

[0044] The language in this paper is only for describing specific embodiments and is not intended to limit the present case. The singular form such as "one", "this", "this", "this" and "this" as used herein also includes the plural form.

[0045] The specifications of the raw materials used in the present case are as follows:

[0046] EPDM: Arlanxeo 2470C, ethylene content 69%, ENB content 4.5%, Mooney viscosity 22MU.

[0047] PP: Sinopec M2600R, melt index (MFR) 25g / 10min, flexural modulus 1100MPa.

[0048] Compatibilizer: SEBS, Kraton G1651, USA.

[0049] Main crosslinking agent: BIBP, bis(tert-butyl peroxyisopropyl) benzene, purity 96%.

[0050] Coagent: TMPTMA, trimethylolpropane trimethacrylate.

[0051] Odor adsorbent: modified zeolite molecular sieve masterbatch.

[0052] Antioxidant: Irganox 1010 and Irgafos 168 compounded at 1:1.

[0053] Comparative coagent: DCP, dicumyl peroxide.

[0054] Examples 1-4: A low-odor thermoplastic vulcanizate for automotive skin, whose raw material formulation is shown in Table 1.

[0055] Table 1 Formulation composition of Examples 1-4 (parts by weight)

[0056]

[0057] The preparation process is as follows:

[0058] Step one: Cut the EPDM 2470C rubber block into irregular small pieces of 3-5 kg using a hydraulic rubber cutter. Put the EPDM small pieces, polypropylene, SEBS, and antioxidant into a 35L intermeshing type internal mixer, set the initial temperature to 140°C, and the rotor speed to 60 rpm. Under the action of shear heat, mix for 8 minutes to raise the material temperature to about 180°C, forming a macroscopically uniform blend, and then granulate through a single screw extruder.

[0059] Step two: Send the granules obtained in step one through a loss weight feeder into the first co-rotating twin screw extruder. After the melting section of the extruder, inject the pre-mixed uniform liquid coagent (BIBP dissolved in TMPTMA) to obtain intermediate particles through dynamic vulcanization. Set the temperature of each section of the extruder to: 140-160°C for the feeding section, 170-190°C for the compression melting section, 190-210°C for the reaction and vulcanization section, 180-200°C for the vacuum devolatilization section, and 170-190°C for the die head; the main screw speed is 400 rpm; the vacuum degree of the vacuum devolatilization section is maintained at -0.09 MPa.

[0060] Step three: Mix the intermediate particles with the odor adsorbent uniformly and send them through the feeder into the second twin screw extruder. Control the temperature of the entire extrusion line at about 180°C to prevent secondary degradation of the material; the vacuum degree is maintained at -0.095 MPa. Utilize the dispersion of the adsorbent and the renewal effect of the melt surface to further remove residual odor substances, and obtain secondary granulation particles through granulation.

[0061] Step 4: The particles obtained in Step 3 were placed in a vacuum oven for baking. The baking temperature was set at 100℃, the time was 2 hours, and the vacuum degree was -0.09 MPa. This step used the condition that the baking temperature was higher than the boiling point of the decomposition product tert-butyl alcohol of BIBP (about 82℃) to forcibly remove it under negative pressure. After cooling and packaging after baking, the low-odor TPV product was obtained.

[0062] In order to verify the technical effect of the present application, three groups of comparative examples were set, and the formulations are shown in Table 2.

[0063] Comparative Example 1 used the traditional DCP system without a co-crosslinking agent, and the preparation method was the same as Example 3, to verify the influence of the type of crosslinking agent; Comparative Example 2 used the formulation of Example 3 but simplified the process, only using mixing plus one extrusion, to verify the influence of the preparation method; Comparative Example 3 used BIBP without a co-crosslinking agent, and the preparation method was the same as Example 3, to verify the synergistic effect of TMPTMA.

[0064] Table 2 Formulation and process differences of comparative examples

[0065]

[0066] Performance test and result analysis:

[0067] The TPV particles prepared in the examples and comparative examples were injection molded into standard test pieces, and the following tests were performed:

[0068] Hardness: tested according to GB / T531.1, 5 points for average value

[0069] Tensile strength and elongation at break: tested according to GB / T528, tensile speed 500 mm / min

[0070] Odor grade: VDA270C3 standard, 3L dry bottle method, heated at 80℃ for 2 hours, evaluated by 3 professional smellers (1st grade no odor ~ 6th grade unbearable).

[0071] Atomization value: DIN75201-B weight method, mg.

[0072] Table 3 Performance test results

[0073]

[0074] Result analysis:

[0075] The hardness of Example 1 is 90A, the tensile strength reaches 19.5 MPa, and it is suitable for use as a high-hardness support material; the hardness of Example 2 is reduced to 60A, the touch is soft, and the tensile strength is still maintained at 14.5 MPa, and it is suitable for a soft-touch skin. Within the protection scope of the formula, the product odor level is stable at 3.0 level, and the atomization value is lower than 0.5 mg, indicating that the "BIBP / TMPTMA + double-stage extrusion + vacuum baking" technical route has universal applicability and effectiveness within the entire claim coverage.

[0076] Comparative Example 1 uses the traditional crosslinking agent DCP, and the odor level is as high as 4.5, and the atomization value is also high, confirming that the use of BIBP instead of DCP is the key chemical basis for improving odor from the source.

[0077] Comparative Example 2 uses the low-odor crosslinking agent BIBP, but does not perform the second extrusion and 100°C vacuum baking, and the odor level is 4.0, indicating that the BIBP decomposition product tert-butyl alcohol cannot be completely removed. Example 1 successfully removes tert-butyl alcohol by 100°C vacuum baking, verifying the necessity of this specific process step.

[0078] Comparative Example 3 uses BIBP and the entire process, but does not add the co-crosslinking agent TMPTMA. Its tensile strength is significantly lower than that of Example 3 under the same conditions, and the odor level is 4.0. This result confirms that TMPTMA plays a key role in the system, which can inhibit the β-chain scission degradation of the peroxide to the polypropylene matrix, thereby reducing the small molecule odor caused by degradation, and improving the crosslinking efficiency and mechanical properties.

[0079] In summary, through the synergy of the specific formula combination and multi-stage processing technology, the TPV material is comprehensively optimized in odor, atomization, and mechanical properties, fully meeting the stringent application requirements of automobile skin.

[0080] The above examples are only for illustrating the technical concept and characteristics of the present application, and the purpose is to enable those skilled in the art to understand the content of the present application and implement it, and it cannot limit the protection scope of the present application. Any equivalent changes or modifications made in accordance with the spirit and essence of the present application shall be covered within the protection scope of the present application.

Claims

1. A low-odor thermoplastic vulcanized rubber for automotive skin, characterized in that: Its raw materials include the following components in parts by weight: 50-80 parts of ethylene-propylene-diolefin copolymer rubber, 20-50 parts of polypropylene resin 5-15 parts compatibilizer 0.5-2.5 parts of compound crosslinking agent, Odor absorbent 0.5~2.0 parts, Antioxidant 0.5~1.0 parts.

2. The low-odor thermoplastic vulcanized rubber for automotive skin according to claim 1, characterized in that: The ethylene-propylene-diolefin copolymer rubber is a semi-crystalline EPDM rubber with an ethylene content of 65%~75%, a third monomer ethyleneide norbornene content of 4.0%~5.5%, and a Mooney viscosity of 20~25MU under ML(1+4) 125℃ conditions.

3. The low-odor thermoplastic vulcanized rubber for automotive skin according to claim 1, characterized in that: The polypropylene resin is a high-flowability, impact-resistant copolymer polypropylene with a density of 0.90~0.91 g / cm³. 3 The melt flow rate at 230℃ / 2.16kg is 15~35g / 10min, and the flexural modulus is 900~1300MPa.

4. The low-odor thermoplastic vulcanized rubber for automotive skin according to claim 1, characterized in that: The compatibilizer is selected from one or a mixture of two of styrene-ethylene-butene-styrene block copolymers and ethylene-octene copolymers.

5. The low-odor thermoplastic vulcanized rubber for automotive skin according to claim 1, characterized in that: The compound crosslinking agent is composed of a main crosslinking agent and a co-crosslinking agent in a mass ratio of 2:1 to 4:1; the main crosslinking agent is bis(tert-butylperoxyisopropyl)benzene with a purity ≥96%; the co-crosslinking agent is trimethylolpropane trimethacrylate.

6. The low-odor thermoplastic vulcanized rubber for automotive skin according to claim 1, characterized in that: The odor adsorbent is selected from one or a mixture of several of modified zeolite molecular sieves, mesoporous silica, and zinc ricinoleate masterbatch, and its pore size distribution is between 0.5 nm and 2.0 nm.

7. The low-odor thermoplastic vulcanized rubber for automotive skin according to claim 1, characterized in that: The antioxidant is selected from one or a mixture of several of pentaerythritol tetrakis[β-(3,5-di-tert-butyl-4-hydroxyphenyl)propionate], tris[2,4-di-tert-butylphenyl]phosphite, and octadecanoate β-(3,5-di-tert-butyl-4-hydroxyphenyl)propionate.

8. A method for preparing a low-odor thermoplastic vulcanizate for automotive skin, characterized in that: The method for preparing a low-odor thermoplastic vulcanizate rubber for automotive skin according to any one of claims 1 to 7 comprises: Step 1: In an internal mixer, add ethylene-propylene-diolefin copolymer rubber, polypropylene resin, compatibilizer and antioxidant according to the formula ratio, and mix at 160℃~190℃ for 5~10 minutes at a speed of 40~80 rpm to form a blended melt. Step 2: The blended melt is fed into the first twin-screw extruder and a compound crosslinking agent is injected. The dynamic vulcanization reaction is carried out under strong shear conditions of 180℃~220℃ and 300~500rpm. The volatiles are removed through the first vacuum exhaust port and the intermediate particles are obtained by extrusion granulation. Step 3: After mixing the intermediate particles with the odor adsorbent, feed them into the second twin-screw extruder and perform melt dispersion and adsorption treatment at 170℃~200℃. Then, perform deep devolatilization through the second vacuum exhaust port and extrude granulation. Step 4: Place the granules obtained in Step 3 in a vacuum oven and bake them at 90℃~110℃ under vacuum for 1~2 hours to obtain the aforementioned low-odor thermoplastic vulcanized rubber product for automotive skin.

9. The method for preparing a low-odor thermoplastic vulcanizate for automotive skin according to claim 8, characterized in that: In both steps two and three, the extrusion process requires the vacuum devolatilization system to be activated, with the vacuum level controlled at -0.08 to -0.1 MPa; a synergistic crosslinking reaction occurs in step two: First, the main crosslinking agent, bis(tert-butylperoxyisopropyl)benzene, decomposes under heating conditions to generate tert-butanol and active free radicals; Subsequently, the crosslinking agent trimethylolpropane trimethacrylate preferentially captures the free radical and attaches it to the molecular chain of the ethylene-propylene-diolefin copolymer rubber through a grafting reaction; Finally, under the action of a shear force field, the ethylene-propylene-diolefin copolymer rubber phase completes crosslinking and achieves phase inversion; the byproduct tert-butanol is removed during the subsequent vacuum heat treatment process.

10. An application of a low-odor automotive skin thermoplastic vulcanizate, characterized in that: The low-odor thermoplastic vulcanized rubber for automotive skin, as described in any one of claims 1 to 7, is used to prepare automotive interior parts including dashboard skin, door panel covers, and center console covers by injection molding, extrusion, or calendering processes, and the products do not release oil mist under high-temperature light irradiation at 80°C to 120°C.

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