Plant-based thermoplastic elastomer material as well as preparation method and application thereof

Abstract

The invention relates to the technical field of elastic materials and refrigerator door sealing strips, in particular to a plant-based thermoplastic elastomer material and a preparation method and application thereof. The plant-based thermoplastic elastomer material contains a chlorinated polyethylene material, a polyethylene material, polyvinyl chloride, a plasticizer, a stabilizer, a lubricant, an antibacterial and mildew-proof agent, plant powder and a coupling and dispersing compatilizer. Wherein the plasticizer is a plant-based plasticizer; the particle size of the plant powder is 12-20 [mu] m. According to the plant-based thermoplastic elastomer material, the elastomer chlorinated polyethylene (CPE) is adopted as a main material, application of a traditional plasticizer is avoided, the low-odor plant-based plasticizer is adopted, odor is reduced, meanwhile, plant powder with plant faint scent is applied as filler, the hardness needed by the refrigerator sealing strip material can meet the sealing effect of a refrigerator, and the service life of the refrigerator is prolonged. And the problem of peculiar smell during door opening of the refrigerator is solved, the low-temperature performance is improved, and the method can be better applied to the field of manufacturing industry needing low-temperature sealing.

Description

Technical Field

[0001] The invention relates to the technical field of elastic materials and refrigerator door sealing strips, and in particular to a plant-based thermoplastic elastomer material and a preparation method and application thereof. Background Art

[0002] The traditional modified polyvinyl chloride (PVC) formula contains 20-40% non-phthalic plasticizers, and all plasticizers on the market have a certain odor. After plasticizing PVC, the odor will escape over time, and a certain odor will accumulate under long-term sealing conditions. Since the refrigerator has a good sealing effect, after long-term storage, the odor of different chemical raw materials in the refrigerator will be slowly released when the refrigerator is unpacked at the user's home. Therefore, the poor customer experience caused by the unpacking odor is a pain point in the refrigerator industry. The industry has added flavors to the materials, but the mixture of flavors and chemical raw materials has an even stranger smell and cannot effectively solve this problem. Summary of the invention

[0003] The purpose of the present invention is to overcome the problem in the prior art that refrigerators release odor after unpacking, which makes customers feel bad. A plant-based thermoplastic elastomer material and a preparation method and application thereof are provided. The plant-based thermoplastic elastomer material uses elastomer chlorinated polyethylene (CPE) as a main material, avoiding the use of traditional plasticizers. The use of low-odor plant-based plasticizers can reduce the odor, and plant powder with plant fragrance is used as filler, which can achieve the hardness required for the refrigerator sealing strip material to meet the sealing effect of the refrigerator, solve the problem of odor when the refrigerator door is opened, and improve its low-temperature performance, so that it can be better applied to the manufacturing field requiring low-temperature sealing.

[0004] In order to achieve the above-mentioned objectives, in the first aspect, the present invention provides a plant-based thermoplastic elastomer material, which contains chlorinated polyethylene material, polyethylene material, polyvinyl chloride, a plasticizer, a stabilizer, a lubricant, an antibacterial and mildew-proof agent, plant powder and a coupling dispersion compatibilizer; wherein the plasticizer is a plant-based plasticizer; and the particle size of the plant powder is 12-20 μm.

[0005] Preferably, the plant-based plasticizer is a citrate plasticizer and / or a trans-aconitate plasticizer.

[0006] Preferably, the chlorinated polyethylene raw material is a CM225 type chlorinated polyethylene material that can be used for producing and processing plant-based thermoplastic elastomers.

[0007] More preferably, the polyethylene material is selected from one or two or more of high-density polyethylene, low-density polyethylene and linear low-density polyethylene.

[0008] Further preferably, the degree of polymerization of the polyvinyl chloride is 1000-1500;

[0009] More preferably, the stabilizer is selected from one or two or more of zinc stearate, calcium stearate, hydrotalcite, pentaerythritol, phosphite and β-diketone.

[0010] More preferably, the lubricant is selected from one or two or more of stearic acid, paraffin and PE wax.

[0011] More preferably, the melting point of the paraffin is 58°C.

[0012] More preferably, the antibacterial and antifungal agent is selected from one or two or more of 4,5-dichloro-2-octyl-4-isothiazoline-3-one, zinc pyrithione and 2-octyl-4-isothiazoline-3-one.

[0013] More preferably, the coupling dispersing compatibilizer is a silane coupling agent and / or maleic anhydride grafted polyethylene.

[0014] Preferably, the weight proportions of the components of the plant-based thermoplastic elastomer material are:

[0015]

[0016]

[0017] In a second aspect, the present invention provides a method for preparing a plant-based thermoplastic elastomer material, the preparation method comprising: 1) mixing a lubricant, a coupling dispersing compatibilizer and a plant powder to prepare a composition A;

[0018] 2) performing a first internal mixing of the polyethylene material, the plasticizer, the stabilizer and the antibacterial and antifungal agent to obtain a composition B;

[0019] 3) subjecting the chlorinated polyethylene material, the composition A and the composition B to a second kneading process for plasticization; wherein, in step 1), the particle size of the plant powder is 12-20 μm; and in step 2), the plasticizer is a plant-based plasticizer.

[0020] Preferably, the plant-based plasticizer is a citrate plasticizer and / or a trans-aconitate plasticizer.

[0021] Preferably, the chlorinated polyethylene raw material is a CM225 type chlorinated polyethylene material that can be used for producing and processing plant-based thermoplastic elastomers.

[0022] More preferably, the polyethylene material is selected from one or two or more of high-density polyethylene, low-density polyethylene and linear low-density polyethylene.

[0023] Further preferably, the degree of polymerization of the polyvinyl chloride is 1000-1500.

[0024] More preferably, the stabilizer is selected from one or two or more of zinc stearate, calcium stearate, hydrotalcite, pentaerythritol, phosphite and β-diketone.

[0025] More preferably, the lubricant is selected from one or two or more of stearic acid, paraffin and PE wax.

[0026] More preferably, the melting point of the paraffin is 58°C.

[0027] More preferably, the antibacterial and antifungal agent is selected from one or two or more of 4,5-dichloro-2-octyl-4-isothiazoline-3-one, zinc pyrithione and 2-octyl-4-isothiazoline-3-one.

[0028] More preferably, the coupling dispersing compatibilizer is a silane coupling agent and / or maleic anhydride grafted polyethylene.

[0029] Preferably, the weight proportions of the components of the plant-based thermoplastic elastomer material are:

[0030]

[0031] Preferably, the mixing conditions include: temperature of 58-65° C., stirring rate of 200-900 rpm, and time of 2-8 min.

[0032] Preferably, the conditions for the first kneading include: pressure of 4-5 MPa, temperature of 90-110° C., stirring rate of 20-50 rpm, and time of 2-8 min.

[0033] More preferably, the conditions for the second kneading include: pressure of 6-7.5 MPa, temperature of 110-130° C., stirring rate of 20-50 rpm, and time of 8-12 min.

[0034] In a third aspect, the present invention provides a plant-based thermoplastic elastomer material prepared by the preparation method described in the second aspect.

[0035] In a fourth aspect, the present invention provides a use of the plant-based thermoplastic elastomer material described in the first aspect or the plant-based thermoplastic elastomer material described in the third aspect in a refrigerator door.

[0036] In a fifth aspect, the present invention provides a method for preparing a refrigerator sealing strip, the preparation method comprising:

[0037] 1) conveying the plant-based thermoplastic elastomer material into an extruder, extruding, shaping, and hot cutting to obtain pellets;

[0038] 2) Extruding the pellets into door seal rubber sleeves through a door seal extruder, and then passing through magnets and welding to obtain finished door seals;

[0039] Wherein, the plant-based thermoplastic elastomer material is the plant-based thermoplastic elastomer material described in the first aspect or the plant-based thermoplastic elastomer material described in the third aspect.

[0040] Preferably, in step 1), the extrusion temperature is 95-140°C.

[0041] More preferably, in step 1), the molding temperature is 100-145°C.

[0042] Through the above technical scheme, the plant-based thermoplastic elastomer material provided by the present invention uses elastomer CPE as the main material by adjusting the formula, avoiding the use of traditional plasticizers and using low-odor plant-based plasticizers instead, which not only reduces the chemical smell of the material, but also improves the low-temperature performance of the material. The filler is further modified plant powder with a particle size of 12-20 μm. The plant powder is loose and porous. When directly applied to the resin, it will absorb a large amount of oil, thereby causing the material to harden and lose the sealing effect. The inventor uses a coupling dispersing compatibilizer and paraffin to modify the plant powder to reduce the oil absorption effect of the plant powder, so that the hardness of the prepared plant-based thermoplastic elastomer material can meet the sealing effect. The addition of modified plant powder not only reduces the density of the plant-based thermoplastic elastomer material to make the sealing material lighter, but also improves the odor of the door sealing material, changing the unacceptable chemical odor to the aromatic plant powder smell, so that the plant-based thermoplastic elastomer material can be better promoted and used.

[0043] At the same time, the preparation method of the plant-based thermoplastic elastomer material is simple and convenient, easy to operate, and suitable for industrial production. DETAILED DESCRIPTION

[0044] The endpoints and any values ​​of the ranges disclosed in this article are not limited to the precise ranges or values, and these ranges or values ​​should be understood to include values ​​close to these ranges or values. For numerical ranges, the endpoint values ​​of each range, the endpoint values ​​of each range and the individual point values, and the individual point values ​​can be combined with each other to obtain one or more new numerical ranges, which should be considered as specifically disclosed in this article.

[0045] In a first aspect, the present invention provides a plant-based thermoplastic elastomer material, which contains chlorinated polyethylene material, polyethylene material, polyvinyl chloride, a plasticizer, a stabilizer, a lubricant, an antibacterial and mildew-proof agent, plant powder and a coupling dispersion compatibilizer; wherein the plasticizer is a plant-based plasticizer; and the particle size of the plant powder is 12-20 μm.

[0046] The plant-based thermoplastic elastomer material provided by the present invention uses elastomer CPE as the main material by adjusting the formula, avoids the use of traditional plasticizers and adopts low-odor plant-based plasticizers instead, which not only reduces the chemical odor of the material, but also improves the low-temperature performance of the material. The filler is further modified plant powder with a particle size of 12-20 μm. The plant powder is loose and porous. When directly applied to the resin, it will absorb a large amount of oil, thereby causing the material to harden and lose the sealing effect. The inventor uses a coupling dispersing compatibilizer and paraffin to modify the plant powder to reduce the oil absorption effect of the plant powder, so that the hardness of the prepared plant-based thermoplastic elastomer material can meet the sealing effect. The addition of the modified plant powder not only reduces the density of the plant-based thermoplastic elastomer material to make the sealing material lighter, but also improves the odor of the door sealing material, changing the unacceptable chemical odor into a fragrant plant powder smell, so that the plant-based thermoplastic elastomer material can be better promoted and used.

[0047] In a preferred embodiment of the present invention, the plant-based plasticizer is a citrate plasticizer and / or a trans-aconitate plasticizer.

[0048] In a preferred embodiment of the present invention, the chlorinated polyethylene raw material is a CM225 type chlorinated polyethylene material that can be used for producing and processing plant-based thermoplastic elastomers.

[0049] In a preferred embodiment of the present invention, the polyethylene material is selected from one or two or more of high-density polyethylene, low-density polyethylene and linear low-density polyethylene.

[0050] In a preferred embodiment of the present invention, the degree of polymerization of the polyvinyl chloride is 1000-1500, preferably 1300, and may also be 1000, 1100, 1200, 1400 or 1500.

[0051] In a preferred embodiment of the present invention, the stabilizer is selected from one or two or more of zinc stearate, calcium stearate, hydrotalcite, pentaerythritol, phosphite and β-diketone.

[0052] In a preferred embodiment of the present invention, the lubricant is selected from one or two or more of stearic acid, paraffin and PE wax.

[0053] In a preferred embodiment of the present invention, the melting point of the paraffin wax is 58°C.

[0054] In a preferred embodiment of the present invention, the antibacterial and mildew-proof agent is selected from one or two or more of 4,5-dichloro-2-octyl-4-isothiazoline-3-one, zinc pyrithione and 2-octyl-4-isothiazoline-3-one.

[0055] In a preferred embodiment of the present invention, the coupling dispersing compatibilizer is a silane coupling agent and / or maleic anhydride grafted polyethylene.

[0056] In a preferred embodiment of the present invention, the weight proportions of the components of the plant-based thermoplastic elastomer material are as follows:

[0057]

[0058] In a second aspect, the present invention provides a method for preparing a plant-based thermoplastic elastomer material, the preparation method comprising: 1) mixing a lubricant, a coupling dispersing compatibilizer and a plant powder to prepare a composition A;

[0059] 2) performing a first internal mixing of the polyethylene material, the plasticizer, the stabilizer and the antibacterial and antifungal agent to obtain a composition B;

[0060] 3) subjecting the chlorinated polyethylene material, the composition A and the composition B to a second kneading process for plasticization; wherein, in step 1), the particle size of the plant powder is 12-20 μm; and in step 2), the plasticizer is a plant-based plasticizer.

[0061] The preparation method of the plant-based thermoplastic elastomer material of the present invention is simple, convenient, easy to operate, and suitable for industrial production.

[0062] In a preferred embodiment of the present invention, the plant-based plasticizer is a citrate plasticizer and / or a trans-aconitate plasticizer.

[0063] In a preferred embodiment of the present invention, the chlorinated polyethylene raw material is a CM225 type chlorinated polyethylene material that can be used for producing and processing plant-based thermoplastic elastomers.

[0064] In a preferred embodiment of the present invention, the polyethylene material is selected from one or two or more of high-density polyethylene, low-density polyethylene and linear low-density polyethylene.

[0065] In a preferred embodiment of the present invention, the degree of polymerization of the polyvinyl chloride is 1000-1500, preferably 1300, and may also be 1000, 1100, 1200, 1400 or 1500.

[0066] In a preferred embodiment of the present invention, the stabilizer is selected from one or two or more of zinc stearate, calcium stearate, hydrotalcite, pentaerythritol, phosphite and β-diketone.

[0067] In a preferred embodiment of the present invention, the lubricant is selected from one or two or more of stearic acid, paraffin and PE wax.

[0068] In a preferred embodiment of the present invention, the melting point of the paraffin wax is 58°C.

[0069] In a preferred embodiment of the present invention, the antibacterial and mildew-proof agent is selected from one or two or more of 4,5-dichloro-2-octyl-4-isothiazoline-3-one, zinc pyrithione and 2-octyl-4-isothiazoline-3-one.

[0070] In a preferred embodiment of the present invention, the coupling dispersing compatibilizer is a silane coupling agent and / or maleic anhydride grafted polyethylene.

[0071] In a preferred embodiment of the present invention, the weight proportions of the components of the plant-based thermoplastic elastomer material are as follows:

[0072]

[0073]

[0074] In a preferred embodiment of the present invention, in step 1), the mixing conditions include: temperature of 58-65° C., stirring rate of 200-900 rpm, and time of 2-8 min.

[0075] In a preferred embodiment of the present invention, in step 2), the conditions of the first kneading include: pressure of 4-5 MPa, temperature of 90-110° C., stirring rate of 20-50 rpm, and time of 2-8 min.

[0076] In a preferred embodiment of the present invention, in step 3), the conditions of the second kneading include: pressure of 6-7.5 MPa, temperature of 110-130° C., stirring rate of 20-50 rpm, and time of 8-12 min.

[0077] In a third aspect, the present invention provides a plant-based thermoplastic elastomer material prepared by the preparation method described in the second aspect.

[0078] In a fourth aspect, the present invention provides a use of the plant-based thermoplastic elastomer material described in the first aspect or the plant-based thermoplastic elastomer material described in the third aspect in a refrigerator door.

[0079] In a fifth aspect, the present invention provides a method for preparing a refrigerator sealing strip, the preparation method comprising:

[0080] 1) conveying the plant-based thermoplastic elastomer material into an extruder, extruding, shaping, and hot cutting to obtain pellets;

[0081] 2) Extruding the pellets into door seal rubber sleeves through a door seal extruder, and then passing through magnets and welding to obtain finished door seals;

[0082] Wherein, the plant-based thermoplastic elastomer material is the plant-based thermoplastic elastomer material described in the first aspect or the plant-based thermoplastic elastomer material described in the third aspect.

[0083] In a preferred embodiment of the present invention, in step 1), the extrusion temperature is 95-140°C.

[0084] In a preferred embodiment of the present invention, in step 1), the molding temperature is 100-145°C.

[0085] The present invention will be described in detail below by way of examples. The experimental methods and equipment described in the following examples are conventional methods and equipment unless otherwise specified.

[0086] Example 1

[0087] (1) Weighing materials: weigh 100 parts of chlorinated polyethylene (CPE), 8 parts of polyethylene (PE), 20 parts of polyvinyl chloride (PVC) (the degree of polymerization of PVC is 1300), 20 parts of acetyl citrate (ATBC), 2 parts of zinc stearate, 4 parts of paraffin (melting point is 58° C.), 0.4 parts of 4,5-dichloro-2-n-octyl-4-isothiazoline-3-one, 30 parts of plant powder, and 1 part of silane coupling agent respectively by mass;

[0088] (2) Modifying the plant powder: Add the weighed paraffin, plant powder and silane coupling agent into a horizontal mixing pot, stir and heat to 60°C, stir for 5 minutes, wait until the molten paraffin is evenly absorbed by the plant powder, cool to room temperature (20-30°C) to obtain a mixture A;

[0089] (3) adding weighed PVC, acetyl citrate (ATBC), zinc stearate and 4,5-dichloro-2-octyl-4-isothiazoline-3-one into an internal kneading pot, mixing and stirring for 5 minutes at a pressure of 4-5 MPa, with a stirring rate of 25 rpm and a temperature increased to 100° C., then adding weighed CPE and the mixture A obtained in step (2) into an internal kneading pot, mixing and stirring at a pressure of 6-7.5 MPa, with a stirring rate of 35 rpm and a temperature increased to 120° C. to obtain a uniformly mixed and properly plasticized CPE / PVC bulk alloy material;

[0090] (4) conveying the CPE / PVC block alloy material obtained in step (3) into a single screw extruder for extrusion processing, with the temperature controlled in the range of 95-140° C. and the die molding temperature of 100-145° C., and finally hot cutting to obtain a plant-based thermoplastic elastomer material;

[0091] (5) Using a single-screw door seal extruder, the plant-based thermoplastic elastomer material obtained in step (4) is extruded into a door seal rubber sleeve according to the customer's cross-sectional drawing requirements, and then subjected to two processes of magnetization and welding to finally obtain a finished door seal strip, which is recorded as B1.

[0092] Example 2

[0093] The method of Example 1 was followed, except that the "30 parts of plant powder" in step (1) was replaced by "50 parts of plant powder" to prepare a finished door seal, which was recorded as B2.

[0094] Example 3

[0095] The method of Example 1 was followed, except that the "PVC degree of polymerization is 1300" in step (1) was replaced by "PVC degree of polymerization is 1000", to obtain a finished door seal, which was designated as B3.

[0096] Comparative Example 1

[0097] Compared with Example 1, the amount of plasticizer is increased, and the plant powder is replaced with calcium carbonate. The specific operation is as follows:

[0098] The method of Example 1 was followed, except that the types and amounts of materials in step (1) were changed to: 100 parts of PVC (PVC polymerization degree: 1300), 70 parts of acetyl citrate (ATBC), 2 parts of zinc stearate, 1 part of paraffin (melting point: 58° C.), 0.4 parts of 4,5-dichloro-2-n-octyl-4-isothiazoline-3-one, 30 parts of calcium carbonate, and 1 part of silane coupling agent were weighed respectively by mass to prepare a finished door seal, which was recorded as D1.

[0099] Comparative Example 2

[0100] Without modifying the plant powder, the specific operation is as follows:

[0101] (1) Weighing materials: Weigh 100 parts of chlorinated polyethylene (CPE), 8 parts of polyethylene (PE), 20 parts of polyvinyl chloride (PVC) (the degree of polymerization of PVC is 1300), 20 parts of acetyl citrate (ATBC), 2 parts of zinc stearate, 0.4 parts of 4,5-dichloro-2-n-octyl-4-isothiazoline-3-one, and 30 parts of plant powder respectively by mass;

[0102] (2) Add the weighed PVC, acetyl citrate (ATBC), zinc stearate, 4,5-dichloro-2-octyl-4-isothiazoline-3-one and plant powder into a high-pressure mixer, stir at a rate of 800 rpm, raise the temperature to 120° C., stir for 5 minutes, and cool to 50° C. in a cold mixer to obtain a mixture A.

[0103] (3) The weighed CPE and the mixture A obtained in step (2) are placed in an internal kneading pot and mixed and stirred at a pressure of 6-7.5 MPa at a stirring rate of 35 rpm and a temperature of 120° C. to obtain a uniformly mixed and properly plasticized CPE / PVC bulk alloy material;

[0104] (4) conveying the CPE / PVC block alloy material obtained in step (3) into a single screw extruder for extrusion processing, with the temperature controlled in the range of 95-140° C. and the die molding temperature of 100-145° C., and finally hot cutting to obtain modified pellets;

[0105] (5) Using a single-screw door seal extruder, the modified material obtained in step (4) is extruded into a door seal rubber sleeve according to the customer's cross-sectional drawing requirements, and then subjected to two processes of magnetization and welding to finally obtain a finished door seal strip, which is recorded as D2.

[0106] Test Example 1

[0107] The properties of the plant-based thermoplastic elastomer material prepared in Example 1 and the thermoplastic elastomer material prepared in Comparative Examples 1-2 were tested. The test items, test standards and test results are shown in Table 1.

[0108] Table 1

[0109]

[0110]

[0111] It can be seen from the results in Table 1 that the density, odor level, HIPS board migration and PCM board adhesion of the door seal made of the plant-based thermoplastic elastomer material prepared in Example 1 of the present invention are far superior to those of the door seal made of the traditional PVC door seal material prepared in Comparative Example 1, and can effectively solve the quality problems such as the odor of the door seal material and the adhesion and corrosion of the ordinary PVC door seal material and the PCM board.

[0112] At the same time, the low-temperature resistance of the door seal made of the plant-based thermoplastic elastomer material prepared in Example 1 of the present invention is better than that of the door seal made of the existing door seal material prepared in Comparative Example 2. The plant-based thermoplastic elastomer material in Example 1 of the present invention effectively reduces the hardness of the material after modifying the plant powder, so that the refrigerator door seal made using the plant-based thermoplastic elastomer material of the present invention has better sealing performance.

[0113] The preferred embodiments of the present invention are described in detail above, but the present invention is not limited thereto. Within the technical concept of the present invention, the technical solution of the present invention can be subjected to a variety of simple modifications, including the combination of various technical features in any other suitable manner, and these simple modifications and combinations should also be regarded as the contents disclosed by the present invention and belong to the protection scope of the present invention.

Claims

1. A plant-based thermoplastic elastomer material, characterized in that: The plant-based thermoplastic elastomer material contains chlorinated polyethylene material, polyethylene material, polyvinyl chloride, plasticizer, stabilizer, lubricant, antibacterial and antifungal agent, plant powder and coupling dispersion compatibilizer; wherein, The plasticizer is a plant-based plasticizer; The particle size of the plant powder is 12-20 μm.

2. The plant-based thermoplastic elastomer material according to claim 1, characterized in that: The plant-based plasticizer is a citrate plasticizer and / or a trans-aconitate plasticizer; Preferably, the chlorinated polyethylene raw material is a CM225 chlorinated polyethylene material that can be used to produce and process plant-based thermoplastic elastomers; More preferably, the polyethylene material is selected from one or two or more of high-density polyethylene, low-density polyethylene and linear low-density polyethylene; Further preferably, the degree of polymerization of the polyvinyl chloride is 1000-1500; More preferably, the stabilizer is selected from one or two or more of zinc stearate, calcium stearate, hydrotalcite, pentaerythritol, phosphite and β-diketone; More preferably, the lubricant is selected from one or two or more of stearic acid, paraffin and PE wax; More preferably, the melting point of the paraffin wax is 58°C; More preferably, the antibacterial and antifungal agent is selected from one or two or more of 4,5-dichloro-2-octyl-4-isothiazoline-3-one, zinc pyrithione and 2-octyl-4-isothiazoline-3-one; More preferably, the coupling dispersing compatibilizer is a silane coupling agent and / or maleic anhydride grafted polyethylene.

3. The plant-based thermoplastic elastomer material according to claim 1 or 2, characterized in that: The weight percentage of each component of the plant-based thermoplastic elastomer material is:

4. A method for preparing a plant-based thermoplastic elastomer material, characterized in that: The preparation method comprises: 1) mixing a lubricant, a coupling dispersing compatibilizer and a plant powder to prepare a composition A; 2) performing a first mixing process on the polyethylene material, the plasticizer, the stabilizer and the antibacterial and antifungal agent to obtain a composition B; 3) subjecting the chlorinated polyethylene material, the composition A and the composition B to a second mixing and plasticizing process; Wherein, in step 1), the particle size of the plant powder is 12-20 μm; In step 2), the plasticizer is a plant-based plasticizer.

5. The preparation method according to claim 4, characterized in that: The plant-based plasticizer is a citrate plasticizer and / or a trans-aconitate plasticizer; Preferably, the chlorinated polyethylene raw material is a CM225 chlorinated polyethylene material that can be used to produce and process plant-based thermoplastic elastomers; More preferably, the polyethylene material is selected from one or two or more of high-density polyethylene, low-density polyethylene and linear low-density polyethylene; Further preferably, the degree of polymerization of the polyvinyl chloride is 1000-1500; More preferably, the stabilizer is selected from one or two or more of zinc stearate, calcium stearate, hydrotalcite, pentaerythritol, phosphite and β-diketone; More preferably, the lubricant is selected from one or two or more of stearic acid, paraffin and PE wax; More preferably, the melting point of the paraffin wax is 58°C; More preferably, the antibacterial and antifungal agent is selected from one or two or more of 4,5-dichloro-2-octyl-4-isothiazoline-3-one, zinc pyrithione and 2-octyl-4-isothiazoline-3-one; More preferably, the coupling dispersing compatibilizer is a silane coupling agent and / or maleic anhydride grafted polyethylene.

6. The preparation method according to claim 4 or 5, characterized in that: The weight percentage of each component of the plant-based thermoplastic elastomer material is:

7. The preparation method according to any one of claims 4 to 6, characterized in that: The mixing conditions include: temperature of 58-65°C, stirring rate of 200-900rpm, and time of 2-8min; Preferably, the conditions of the first banburying include: pressure of 4-5 MPa, temperature of 90-110° C., stirring rate of 20-50 rpm, and time of 2-8 min; More preferably, the conditions for the second kneading include: pressure of 6-7.5 MPa, temperature of 110-130° C., stirring rate of 20-50 rpm, and time of 8-12 min.

8. A plant-based thermoplastic elastomer material prepared according to the preparation method according to any one of claims 4 to 7.

9. Use of the plant-based thermoplastic elastomer material according to any one of claims 1 to 3 or the plant-based thermoplastic elastomer material according to claim 8 in a refrigerator door.

10. A method for preparing a refrigerator sealing strip, characterized in that: The preparation method comprises: 1) conveying the plant-based thermoplastic elastomer material into an extruder, extruding, shaping, and hot cutting to obtain pellets; 2) Extruding the pellets into door seal rubber sleeves through a door seal extruder, and then passing through magnets and welding to obtain finished door seals; Wherein, the plant-based thermoplastic elastomer material is the plant-based thermoplastic elastomer material according to any one of claims 1 to 3 or the plant-based thermoplastic elastomer material according to claim 8; Preferably, in step 1), the extrusion temperature is 95-140°C; More preferably, in step 1), the molding temperature is 100-145°C.

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