Reclaimed oil bio-based plastic modified rubber material and preparation method thereof

Abstract

The invention discloses a reclaimed oil bio-based plastic modified rubber material and a preparation method thereof, and the reclaimed oil bio-based plastic modified rubber material comprises the following components by weight: 30-70 parts of bio-based plastic, 10-40 parts of natural rubber, 5-25 parts of plant fiber, 5-50 parts of calcium powder, 0.3-1.5 parts of a vulcanizing agent, 0.8-2 parts of zinc oxide, 0.3-0.9 part of an accelerator, and 1-10 parts of a foaming agent. The invention relates to the technical field of rubber materials, in particular to an antibacterial and mildew-proof rubber material. The regenerated oil-based bio-based plastic is innovatively applied to modification of a rubber material, a new application way of the bio-based material in the field of rubber-plastic compounding is developed, a new thought is provided for solving the environmental and resource problems caused by a petroleum-based material, and the selection of the raw materials not only embodies effective utilization of renewable resources, but also has the advantages of environmental protection and environmental protection. The carbon emission is reduced, and the development trend of current green materials is met.

Description

Technical Field

[0001] The invention relates to the technical field of rubber materials, and in particular to a recycled oil bio-based plastic modified rubber material and a preparation method thereof. Background Art

[0002] Rubber materials play an important role in modern industry. In the automotive field, tires and seals rely on the high elasticity and wear resistance of rubber to ensure driving safety and stability; in the shoemaking industry, the anti-slip, wear resistance and elasticity of rubber soles improve the wearing experience and life of shoes; industrial rubber products such as conveyor belts and hoses rely on rubber properties to adapt to complex industrial environments and high-intensity operations.

[0003] However, traditional rubber faces many difficulties. It mainly comes from oil resources. The oil depletion crisis has challenged the sustainable production of traditional rubber. In addition, the production process is energy-intensive and polluting, which is not in line with the concept of environmental protection. In terms of performance, it is easy to age at high temperatures and its wear resistance declines under high loads, making it difficult to meet the high-performance and diversified needs of modern industry. Although recycled oil can be used for rubber modification and can improve processing performance as a plasticizer, such as shortening mixing time, reducing Mooney viscosity, enhancing fluidity, and improving flexibility and cold resistance, it also has defects. It will cause the mechanical properties of rubber such as strength and hardness to decline, and excessive addition will also destroy dimensional stability.

[0004] Most of the existing rubber modification technologies are single component addition or simple blending, such as using only fillers such as carbon black to enhance strength and wear resistance, or only adding petroleum-based plasticizers to improve processability, which makes it difficult to balance environmental protection, high performance and multi-functions. When recycled oil and bio-based plastics are used in rubber modification, the synergistic effect is not fully exerted due to problems with the blending process and formula ratio. Although some modified rubbers have made progress in environmental protection and flexibility, their tensile strength is greatly reduced or processing problems such as phase separation occur. Therefore, it is urgent to develop a new rubber modification technology that can effectively combine the advantages of recycled oil and bio-based plastics, overcome shortcomings, and have both environmental protection and excellent comprehensive performance to meet the high standards of modern industry for rubber materials. Summary of the invention

[0005] In order to solve the above technical problems, the present invention provides a recycled oil bio-based plastic modified rubber material, which is composed of the following components in parts by weight: 30-70 parts by weight of bio-based plastic, 10-40 parts by weight of natural rubber, 5-25 parts by weight of plant fiber, 5-50 parts by weight of calcium powder, 0.3-1.5 parts by weight of vulcanizing agent, 0.8-2 parts by weight of zinc oxide, 0.3-0.9 parts by weight of accelerator, 1-10 parts by weight of foaming agent, 0.3-1 parts by weight of stearic acid, 0.3-1 parts by weight of zinc stearate, and 3-8 parts by weight of modified antibacterial and mildew-proof filler.

[0006] Furthermore, the bio-based plastic is a plastic made from a bio-based material extracted from recycled oil, and is polyethylene; The natural rubber is No. 5 rubber; The vulcanizing agent is di-tert-butyl diisopropylbenzene peroxide; The accelerator is 2-mercaptobenzothiazole; The foaming agent is 4,4'-oxybisbenzenesulfonyl hydrazide.

[0007] Furthermore, the preparation method of the modified antibacterial and mildew-proof filler comprises the following steps: The first step is to take 100 parts by weight of a natural mineral filler, soak it in 500-1000 parts by weight of a sodium hydroxide solution, filter it, wash it to neutrality, and then dry it to obtain an alkali-treated filler; Step 2: adding 100 parts by weight of the filler treated with alkali to 500-1000 parts by weight of a solution containing a silane coupling agent, stirring to react, filtering, washing, and drying after the reaction is completed to obtain a filler modified with a silane coupling agent; Step 3: Add 100 parts by weight of the filler modified by the silane coupling agent into 500-1000 parts by weight of a mixed solution containing an antibacterial agent, a mildew preventer and a mercapto-containing organic silane coupling agent, stir the mixture under ultrasonic conditions to react, filter, wash and dry after the reaction to obtain a modified antibacterial and mildew preventer filler.

[0008] Furthermore, in the first step, the natural mineral filler is zeolite, the particle size needs to be controlled within the range of 10-100 μm, the concentration of the sodium hydroxide solution is 5-10%, the soaking time is 2-4 hours, the soaking temperature is 50-70°C, the drying temperature is 100-120°C, and the drying time is 2-3 hours.

[0009] Furthermore, in the second step, the silane coupling agent is γ-aminopropyltriethoxysilane, the solvent in the solution containing the silane coupling agent is anhydrous ethanol, and the concentration of the solution containing the silane coupling agent is 2-5%; The stirring temperature is 60-80° C., the stirring time is 3-5 hours, the drying temperature is 80-100° C., and the drying time is 1-2 hours.

[0010] Furthermore, in the third step, the antibacterial agent is a nanosilver particle solution, and the amount used is 5-10 parts by weight; The mildew preventer is an isothiazolinone mildew preventer solution, and the dosage is 10-20 parts by weight; The mercapto-containing organic silane coupling agent is γ-mercaptopropyltriethoxysilane, and the amount used is 5-15 parts by weight; The solvent of the mixed solution is an organic solvent or a mixed system of water and an organic solvent.

[0011] Furthermore, the stirring reaction time under the ultrasonic condition is 2-4 hours, the ultrasonic power is 200-400W, the reaction temperature is 30-50°C, the drying temperature is 60-80°C, and the drying time is 1-2 hours.

[0012] A method for preparing a recycled oil bio-based plastic modified rubber material comprises the following steps: Step 1, placing the bio-based plastic, natural rubber, plant fiber, calcium powder and all additives in a vacuum drying oven for drying; Step 2, putting the dried natural rubber into an internal mixer for plasticization, and then sequentially adding bio-based plastic, plant fiber, calcium powder, zinc oxide, accelerator, foaming agent, stearic acid, zinc stearate, modified antibacterial and mildew-proof filler, and performing preliminary mixing, and then evenly sprinkling the vulcanizer on the surface of the mixed rubber material until the mixing is completed; Step 3, the mixed rubber material is granulated by a granulator, and then the granules are injected into a specific mold to form a blank; Step 4: Put the sheet or injection-molded material into a reactor and fill it with nitrogen with a purity of more than 99.9% for supercritical foaming.

[0013] Furthermore, in step 1, the drying temperature is 60-80° C., the drying time is 4-6 hours, and the moisture content of each raw material is less than 0.5%; In the step 2, the rotor speed of the internal mixer is 40-60 rpm, the temperature is 50-70°C, and the plasticizing time is 3-5 minutes. In the step 2, the mixing temperature is 80-140° C., the mixing time is 8-12 minutes, and the filling factor of the internal mixer is 0.6-0.8.

[0014] Furthermore, in the step 3, the screw speed of the granulator is 80-120 rpm and the temperature is 100-120° C.; The mold temperature is 100-200℃ and the injection pressure is 20-100MPa; The supercritical foaming process in step 4 is as follows: first, the pressure in the reactor is increased to 10-25 MPa, the temperature is increased to 160-200° C., and maintained in this supercritical state for 10-120 minutes, and then the pressure is rapidly reduced to 0.5-5 MPa, while the temperature remains unchanged.

[0015] The present invention provides a recycled oil bio-based plastic modified rubber material and a preparation method thereof, which has the following beneficial effects: 1. The use of recycled oil-based bio-based plastics reduces dependence on petroleum resources and reduces carbon emissions. The use of recycled oil realizes the recycling of waste oil, which is in line with the concept of sustainable development and helps to alleviate environmental pressure and cope with the energy crisis.

[0016] 2. Natural rubber itself has a certain degree of biodegradability, which further improves the environmental friendliness of the material in the entire material system and reduces the long-term impact of the material on the environment after the end of its service life.

[0017] 3. The addition of plant fiber enhances the strength and rigidity of the material, plays a good reinforcing effect, improves the comprehensive mechanical properties of the material, and makes it less likely to deform and damage when subjected to external forces. The addition of calcium powder further optimizes the material's hardness, heat resistance and other physical properties, so that the material can maintain stable performance under different environmental conditions.

[0018] 4. The rational use of additives such as vulcanizers and activators promotes the cross-linking reaction between rubber molecules, forms a stable three-dimensional network structure, improves key performance indicators such as strength, elasticity and heat resistance of the material, and ensures that the performance of the material does not decrease significantly during long-term use.

[0019] 5. The innovative application of recycled oil-based bio-based plastics in the modification of rubber materials has opened up a new application path for bio-based materials in the field of rubber-plastic composites, and provided new ideas for solving the environmental and resource problems caused by petroleum-based materials. The choice of this raw material not only reflects the effective use of renewable resources, but also has significant advantages in reducing carbon emissions, which is in line with the current trend of green material development.

[0020] 6. A modified antibacterial and anti-mildew filler obtained through multiple modification reactions has been developed. This filler integrates multiple functions (antibacterial, anti-mildew, anti-corrosion, and conductive) through a unique formula design and preparation process. The application of this multifunctional filler is relatively new in the field of rubber materials. It can give the material comprehensive performance advantages and meet the urgent needs of modern industry for multifunctional materials, which is different from the use of traditional single-function fillers. DETAILED DESCRIPTION

[0021] The following specific embodiments further describe the present invention in detail. The embodiments of the present invention are provided for the purpose of illustration and description, and are not intended to be exhaustive or to limit the present invention to the disclosed forms. Many modifications and variations will be apparent to those of ordinary skill in the art. The embodiments are selected and described to better illustrate the principles and practical applications of the present invention, and to enable those of ordinary skill in the art to understand the present invention and thereby design various embodiments with various modifications suitable for specific uses.

[0022] Example 1, raw material preparation: It uses 50 parts by weight of recycled oil-based polyethylene bio-based plastic, 15 parts by weight of No. 5 rubber, 15 parts by weight of plant fiber, 25 parts by weight of calcium powder, 0.3 parts by weight of di-tert-butyl peroxide diisopropylbenzene, 1.5 parts by weight of zinc oxide, 0.6 parts by weight of 2-mercaptobenzothiazole, 4 parts by weight of 4,4'-oxybisbenzenesulfonyl hydrazide, 0.5 parts by weight of stearic acid, 0.6 parts by weight of zinc stearate, and 6 parts by weight of modified antibacterial and mildew-proof filler.

[0023] The preparation steps of modified antibacterial and mildew-proof filler: Step 1: Take 100 parts by weight of zeolite (particle size 40 μm), place it in 600 parts by weight of 6% sodium hydroxide solution, soak it at 65°C for 2.5 hours, filter and wash it to neutrality, and dry it at 110°C for 2.5 hours.

[0024] Step 2: Add the alkali-treated zeolite to 600 parts by weight of a solution containing 12 parts of γ-aminopropyltriethoxysilane (concentration of 2.5%), stir and react at 65°C for 3.5 hours, filter, wash and dry at 85°C for 1.5 hours after the reaction.

[0025] Step 3: adding the zeolite modified by the silane coupling agent into a mixed solution of 600 parts by weight of a solution containing nanosilver particles (the concentration of the nanosilver particles is 1%), an isothiazolinone mildewcide solution (the concentration of the isothiazolinone mildewcide solution is 2%) and γ-mercaptopropyltriethoxysilane (the concentration of γ-mercaptopropyltriethoxysilane is 1.3%), wherein ethanol is used as the solvent, stirring and reacting at an ultrasonic power of 250 W and 35° C. for 2.5 hours, filtering, washing and drying at 70° C. for 1.5 hours after the reaction is completed.

[0026] Preparation process: Raw material pretreatment: drying at 65°C for 4.5 hours.

[0027] Mixing: Rubber No. 5 was plasticized for 3.5 minutes (rotor speed 45 rpm, temperature 55°C), and then other components were added in sequence and mixed at 95°C for 9 minutes (internal mixer filling factor 0.65).

[0028] Granulation and injection molding: The mixed rubber material is granulated by a granulator (screw speed 90 rpm, temperature 105°C) and then injected into a mold (mold temperature 140°C, injection pressure 80MPa) to form a blank.

[0029] Supercritical foaming process: put the blank into the reactor, fill it with nitrogen (purity 99.95%), increase the pressure to 20MPa, increase the temperature to 180℃, maintain for 60 minutes, then quickly reduce the pressure to 2MPa and keep the temperature unchanged.

[0030] The obtained foamed material can be used in the field of building insulation. Its foaming ratio is 6 times, the thermal conductivity is 0.035W / m·K, it has good sound absorption performance, and the sound absorption coefficient is 0.45. It also has antibacterial, mildew-proof and corrosion-resistant properties. It will not breed mold if placed in a humid environment for a long time. The antibacterial rate against common bacteria is above 98.5%. The mass loss rate in an acidic and alkaline environment is about 42% lower than that of ordinary foamed materials.

[0031] Example 2, raw material preparation: It uses 30 parts by weight of recycled oil-based polyethylene bio-based plastic, 10 parts by weight of No. 5 rubber, 5 parts by weight of plant fiber, 5 parts by weight of calcium powder, 0.5 parts by weight of di-tert-butyl peroxide diisopropylbenzene, 0.8 parts by weight of zinc oxide, 0.3 parts by weight of 2-mercaptobenzothiazole, 1 part by weight of 4,4'-oxybisbenzenesulfonylhydrazine, 0.3 parts by weight of stearic acid, 0.3 parts by weight of zinc stearate, and 3 parts by weight of modified antibacterial and mildew-proof filler.

[0032] The preparation steps of modified antibacterial and mildew-proof filler: Step 1: Take 100 parts by weight of zeolite (particle size 10 μm), place it in 500 parts by weight of 5% sodium hydroxide solution, soak it at 50°C for 2 hours, filter and wash it to neutrality, and dry it at 100°C for 2 hours.

[0033] Step 2: Add the alkali-treated zeolite to 500 parts by weight of a solution containing γ-aminopropyltriethoxysilane (γ-aminopropyltriethoxysilane concentration is 2%), stir and react at 60°C for 3 hours, filter, wash and dry at 80°C for 1 hour after the reaction.

[0034] Step 3: adding the zeolite modified by the silane coupling agent to a mixed solution of 500 parts by weight containing a nanosilver particle solution (the concentration of the nanosilver particle solution is 1%), an isothiazolinone mildewcide solution (the concentration of the isothiazolinone mildewcide solution is 2%), and γ-mercaptopropyltriethoxysilane (the concentration of γ-mercaptopropyltriethoxysilane is 1%), wherein the solvent is ethanol, stirring and reacting at an ultrasonic power of 200 W and 30° C. for 2 hours, filtering, washing, and drying at 60° C. for 1 hour after the reaction is completed; Preparation process: Raw material pretreatment: drying at 60°C for 4 hours.

[0035] Mixing: Rubber No. 5 was plasticized for 3 minutes (rotor speed 40 rpm, temperature 50°C), and then other components were added in sequence and mixed at 80°C for 8 minutes (internal mixer filling factor 0.6).

[0036] Granulation and injection molding: The mixed rubber material is granulated by a granulator (screw speed 80 rpm, temperature 100°C) and then injected into a mold (mold temperature 100°C, injection pressure 20MPa) to form a blank.

[0037] Supercritical foaming process: put the blank into the reactor, fill it with nitrogen (purity 99.95%), increase the pressure to 10MPa, increase the temperature to 160℃, maintain for 10 minutes, then quickly reduce the pressure to 0.5MPa and keep the temperature unchanged.

[0038] The obtained foamed material can be used in the field of building insulation. Its foaming ratio is 4 times, the thermal conductivity is 0.042W / m·K, it has good sound absorption performance, and the sound absorption coefficient is 0.32. It also has antibacterial, mildew-proof and corrosion-resistant properties. It will not breed mold if placed in a humid environment for a long time. The antibacterial rate against common bacteria is above 90%. The mass loss rate in an acidic and alkaline environment is about 35% lower than that of ordinary foamed materials.

[0039] Example 3, raw material preparation: It adopts 70 parts by weight of recycled oil-based polyethylene bio-based plastic, 40 parts by weight of No. 5 rubber, 25 parts by weight of plant fiber, 50 parts by weight of calcium powder, 1.5 parts by weight of di-tert-butyl peroxide diisopropylbenzene, 2 parts by weight of zinc oxide, 0.9 parts by weight of 2-mercaptobenzothiazole, 10 parts by weight of 4,4'-oxybisbenzenesulfonylhydrazide, 1 part by weight of stearic acid, 1 part by weight of zinc stearate, and 8 parts by weight of modified antibacterial and mildew-proof filler.

[0040] The preparation steps of modified antibacterial and mildew-proof filler: Step 1: Take 100 parts by weight of zeolite (particle size 100 μm), place it in 1000 parts by weight of 10% sodium hydroxide solution, soak it at 70°C for 4 hours, filter and wash it to neutrality, and dry it at 120°C for 3 hours.

[0041] Step 2: Add the alkali-treated zeolite to 1000 parts by weight of a solution containing γ-aminopropyltriethoxysilane (γ-aminopropyltriethoxysilane concentration is 5%), stir and react at 80°C for 5 hours, filter, wash and dry at 100°C for 2 hours after the reaction.

[0042] Step 3: adding the zeolite modified by the silane coupling agent to a mixed solution of 1000 parts by weight containing a nanosilver particle solution (the concentration of the nanosilver particle solution is 1%), an isothiazolinone mildewcide solution (the concentration of the isothiazolinone mildewcide solution is 2%), and γ-mercaptopropyltriethoxysilane (the concentration of γ-mercaptopropyltriethoxysilane is 1.5%), wherein the solvent is ethanol, stirring and reacting at an ultrasonic power of 400 W and 50° C. for 4 hours, filtering, washing, and drying at 80° C. for 2 hours after the reaction is completed; Preparation process: Raw material pretreatment: drying at 80°C for 6 hours.

[0043] Mixing: Rubber No. 5 was plasticized for 5 minutes (rotor speed 60 rpm, temperature 70°C), and then other components were added in sequence and mixed at 140°C for 12 minutes (internal mixer filling factor 0.8).

[0044] Granulation and injection molding: The mixed rubber material is granulated by a granulator (screw speed 120 rpm, temperature 120°C) and then injected into a mold (mold temperature 200°C, injection pressure 100MPa) to form a blank.

[0045] Supercritical foaming process: put the blank into the reactor, fill it with nitrogen (purity 99.95%), increase the pressure to 25MPa, increase the temperature to 200℃, maintain for 120 minutes, then quickly reduce the pressure to 5MPa and keep the temperature unchanged.

[0046] The obtained foamed material can be used in the field of building insulation. Its foaming ratio is 7 times, the thermal conductivity is 0.06W / m·K, it has good sound absorption performance, and the sound absorption coefficient is 0.38. It also has antibacterial, mildew-proof and corrosion-resistant properties. It will not breed mold if placed in a humid environment for a long time. The antibacterial rate against common bacteria is above 95%. The mass loss rate in an acidic and alkaline environment is about 38% lower than that of ordinary foamed materials.

[0047] In summary, Example 2 has a foaming ratio of 4 times, a thermal conductivity of 0.042 W / m·K, a sound absorption coefficient of 0.32, an antibacterial rate of more than 90%, and an acid-base environment mass loss rate reduced by about 35%; Example 1 has a foaming ratio of 6 times, a thermal conductivity of 0.035 W / m·K, a sound absorption coefficient of 0.45, an antibacterial rate of more than 98.5%, and a mass loss rate reduced by about 42%; Example 3 has a foaming ratio of 7 times, a thermal conductivity of 0.06 W / m·K, a sound absorption coefficient of 0.38, an antibacterial rate of more than 95%, and a mass loss rate reduced by about 38%. It can be seen that the recycled oil bio-based plastic modified rubber material prepared in Example 1 has the best performance.

[0048] Obviously, the described embodiments are only some embodiments of the present invention, not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field and related fields without creative work should fall within the scope of protection of the present invention. The structures, devices and operating methods not specifically described and explained in the present invention are implemented according to the conventional means in the field unless otherwise specified and limited.

Claims

1. A recycled oil bio-based plastic modified rubber material, characterized in that: The invention is composed of the following components in parts by weight: 30-70 parts by weight of bio-based plastic, 10-40 parts by weight of natural rubber, 5-25 parts by weight of plant fiber, 5-50 parts by weight of calcium powder, 0.3-1.5 parts by weight of vulcanizing agent, 0.8-2 parts by weight of zinc oxide, 0.3-0.9 parts by weight of accelerator, 1-10 parts by weight of foaming agent, 0.3-1 parts by weight of stearic acid, 0.3-1 parts by weight of zinc stearate and 3-8 parts by weight of modified antibacterial and mildew-proof filler.

2. The recycled oil bio-based plastic modified rubber material according to claim 1, characterized in that: The bio-based plastic is a plastic made from bio-based materials extracted from recycled oil, and is polyethylene; The natural rubber is No. 5 rubber; The vulcanizing agent is di-tert-butyl diisopropylbenzene peroxide; The accelerator is 2-mercaptobenzothiazole; The foaming agent is 4,4'-oxybisbenzenesulfonyl hydrazide.

3. The recycled oil bio-based plastic modified rubber material according to claim 1, characterized in that: The preparation method of the modified antibacterial and mildew-proof filler comprises the following steps: The first step is to take 100 parts by weight of a natural mineral filler, soak it in 500-1000 parts by weight of a sodium hydroxide solution, filter it, wash it to neutrality, and then dry it to obtain an alkali-treated filler; Step 2: adding 100 parts by weight of the filler treated with alkali to 500-1000 parts by weight of a solution containing a silane coupling agent, stirring to react, filtering, washing, and drying after the reaction is completed to obtain a filler modified with a silane coupling agent; Step 3: Add 100 parts by weight of the filler modified by the silane coupling agent into 500-1000 parts by weight of a mixed solution containing an antibacterial agent, a mildew preventer and a mercapto-containing organic silane coupling agent, stir the mixture under ultrasonic conditions to react, filter, wash and dry after the reaction to obtain a modified antibacterial and mildew preventer filler.

4. The recycled oil bio-based plastic modified rubber material according to claim 3, characterized in that: In the first step, the natural mineral filler is zeolite, the particle size needs to be controlled within the range of 10-100 μm, and the concentration of the sodium hydroxide solution is 5-10%; In the first step, the soaking time is 2-4 hours and the soaking temperature is 50-70° C.; In the first step, the drying temperature is 100-120° C. and the drying time is 2-3 hours.

5. The recycled oil bio-based plastic modified rubber material according to claim 3, characterized in that: In the second step, the silane coupling agent is γ-aminopropyltriethoxysilane, the solvent in the solution containing the silane coupling agent is anhydrous ethanol, and the concentration of the solution containing the silane coupling agent is 2-5%; In the second step, the stirring temperature is 60-80°C and the stirring time is 3-5 hours; In the second step, the drying temperature is 80-100° C. and the drying time is 1-2 hours.

6. The recycled oil bio-based plastic modified rubber material according to claim 3, characterized in that: In the third step, the antibacterial agent is a nanosilver particle solution, and the amount used is 5-10 parts by weight; The mildew preventer is an isothiazolinone mildew preventer solution, and the dosage is 10-20 parts by weight; The mercapto-containing organic silane coupling agent is γ-mercaptopropyltriethoxysilane, and the amount used is 5-15 parts by weight; The solvent of the mixed solution is an organic solvent or a mixed system of water and an organic solvent.

7. The recycled oil bio-based plastic modified rubber material according to claim 3, characterized in that: In the third step, the stirring reaction time under ultrasonic conditions is 2-4 hours, the ultrasonic power is 200-400W, and the reaction temperature is 30-50°C; In the third step, the drying temperature is 60-80° C. and the drying time is 1-2 hours.

8. A method for preparing a recycled oil bio-based plastic modified rubber material, characterized in that: The following steps are included: Step 1, placing the bio-based plastic, natural rubber, plant fiber, calcium powder and all additives in a vacuum drying oven for drying; Step 2, putting the dried natural rubber into an internal mixer for plasticization, and then sequentially adding bio-based plastic, plant fiber, calcium powder, zinc oxide, accelerator, foaming agent, stearic acid, zinc stearate, modified antibacterial and mildew-proof filler, and performing preliminary mixing, and then evenly sprinkling the vulcanizer on the surface of the mixed rubber material until the mixing is completed; Step 3, the mixed rubber material is granulated by a granulator, and then the granules are injected into a specific mold to form a blank; Step 4: Put the sheet or injection-molded material into a reactor and fill it with nitrogen with a purity of more than 99.9% for supercritical foaming.

9. The method for preparing a recycled oil bio-based plastic modified rubber material according to claim 8, characterized in that: In the step 1, the drying temperature is 60-80°C, the drying time is 4-6 hours, and the moisture content of each raw material is less than 0.5%; In the step 2, the rotor speed of the internal mixer is 40-60 rpm, the temperature is 50-70°C, and the plasticizing time is 3-5 minutes. In the step 2, the mixing temperature is 80-140° C., the mixing time is 8-12 minutes, and the filling factor of the internal mixer is 0.6-0.

8.

10. The method for preparing a recycled oil bio-based plastic modified rubber material according to claim 8, characterized in that: In the step 3, the screw speed of the granulator is 80-120 rpm and the temperature is 100-120°C; In the step 3, the mold temperature is 100-200°C and the injection pressure is 20-100MPa; In step 4, the supercritical foaming process: first, the pressure in the reactor is increased to 10-25 MPa, the temperature is increased to 160-200°C, and maintained in this supercritical state for 10-120 minutes, and then the pressure is rapidly reduced to 0.5-5 MPa, and the temperature is kept unchanged.