Preparation method of high-performance weather-resistant EPDM (ethylene-propylene-diene monomer) colored rubber particles

Abstract

The invention discloses a preparation method of high-performance weather-resistant EPDM (Ethylene-Propylene-Diene Monomer) colored rubber particles, and belongs to the technical field of rubber materials. The preparation method comprises the following steps: by taking EPDM rubber as a matrix, adding a transferable weather-resistant master batch, a dynamic cross-linking agent, a fluorosilicone hydrophobic auxiliary agent, color paste, a reinforcing filler and an environment-friendly vulcanization system, and carrying out banburying and sectional temperature control extrusion granulation; the weather-resistant and hydrophobic components spontaneously migrate to the surfaces of the particles, an integrated weather-resistant and hydrophobic shell layer is formed in situ, and a dynamic cross-linked network is built in the shell layer. The obtained particles have high mechanical property, excellent weather resistance and hydrophobic self-cleaning function, the process is simple, post-treatment is not needed, the particles are suitable for industrial production, and the problems that traditional EPDM particles are easy to age, fade and stain are effectively solved.

Description

Technical Field

[0001] This invention relates to the field of rubber materials technology, specifically to a method for preparing high-performance weather-resistant EPDM colored rubber granules. Background Technology

[0002] Ethylene propylene diene monomer (EPDM) colored rubber granules are widely used in outdoor applications such as sports fields and park pathways due to their excellent ozone resistance and high / low temperature resistance. However, existing products have significant shortcomings: traditional weather-resistant modification often relies on the addition of a single weather-resistant agent, lacking synergistic design with the material structure, leading to aging, chalking, and decreased color fastness after long-term outdoor use; hydrophobic properties are mostly achieved through post-coating, resulting in coating peeling, complex processes, and difficulty in simultaneously achieving both weather resistance and hydrophobicity; furthermore, conventional crosslinking systems cannot balance mechanical properties and post-aging stability, limiting the granule's lifespan. Although dynamic vulcanization technology exists to improve material compatibility, it lacks surface functionalization design and fails to address the core requirement of synergistic optimization of weather resistance, hydrophobicity, and mechanical properties. Therefore, developing an EPDM colored rubber granule that requires no post-treatment, can form an integrated weather-resistant and hydrophobic structure in situ, and enhances mechanical properties and aging stability through dynamic crosslinking has become a pressing technical challenge for the industry. Summary of the Invention

[0003] To address the problems of easy aging and fading, easy peeling of hydrophobic coating, and difficulty in achieving both performance and durability in existing EPDM colored rubber granules, this invention proposes a high-performance weather-resistant EPDM colored rubber granule and its preparation method. By using a specific ratio of weather-resistant masterbatch, fluorosilicone hydrophobic additives, and dynamic crosslinking agents, combined with a segmented temperature-controlled process, an integrated weather-resistant and hydrophobic shell is formed in situ. This simultaneously achieves excellent weather resistance, hydrophobic self-cleaning properties, and high mechanical properties. The process is simple, requires no post-processing, and is cost-controllable, making it suitable for outdoor applications.

[0004] To achieve the above objectives, the present invention adopts the following technical solution: A high-performance, weather-resistant EPDM colored rubber granule, the rubber granule being prepared from the following raw materials in parts by weight: EPDM rubber 60-75 parts, migratable weather-resistant masterbatch 1.5-6 parts, dynamic crosslinking agent 0.3-2 parts, fluorosilicone hydrophobic additive 0.8-3 parts, colored pigment 2-8 parts, reinforcing filler 15-35 parts, environmentally friendly vulcanizing composite component 0.7-3 parts; The environmentally friendly vulcanizing composite component is a compound of peroxide vulcanizing agent and crosslinking agent; the rubber particles have an in-situ weather-resistant and hydrophobic integrated shell layer formed on their surface, and the particle size is 1-5mm.

[0005] Optionally, the migratable weather-resistant masterbatch is a compound of hindered amine light stabilizer, benzophenone ultraviolet absorber and polyolefin wax, with a mass ratio of 1:1:2-3.

[0006] Optionally, the dynamic crosslinking agent is a maleimide-based or disulfide-type dynamic crosslinking agent, selected from N,N'-m-phenylenebismaleimide or dibenzothiazole disulfide.

[0007] Optionally, the fluorosilicone hydrophobic additive is a fluorinated polysiloxane or a fluorosilane coupling agent, wherein the fluorine content is 15-30 wt%.

[0008] Optionally, in the environmentally friendly vulcanizing composite component, the peroxide vulcanizing agent is selected from one or more of dicumyl peroxide, benzoyl peroxide, and 2,5-dimethyl-2,5-di-tert-butylperoxyhexane; the crosslinking aid is selected from one or more of triallyl isocyanurate, trimethylolpropane triacrylate, and divinylbenzene.

[0009] Optionally, the reinforcing filler is one or more of nano-silica, carbon black, and calcium carbonate.

[0010] Optionally, the rubber particles have a QUV aging resistance time of 2000-3000h, a surface water contact angle of 105°-120°, a tensile strength of 10-15MPa, and a color fastness of grade 7-8.

[0011] Optionally, the preparation method of the high-performance weather-resistant EPDM colored rubber granules is as follows: S1. Dry the EPDM rubber in an oven at 60-70℃ for 2-4 hours to remove surface moisture; dry the reinforcing filler at 110-120℃ for 4-6 hours, controlling the moisture content to ≤0.5wt%. S2. Put EPDM rubber into an internal mixer. After the rubber softens for 5-8 minutes, add reinforcing filler, migratable weather-resistant masterbatch, dynamic crosslinking agent, fluorosilicone hydrophobic additive, and color paste in sequence. Finally, add environmentally friendly vulcanizing composite components. S3. Control the rotor speed of the internal mixer to 50-80 r / min, and the total mixing time to 15-30 min. Specifically, premix at 80-85℃ for 5-10 min to ensure the materials are initially mixed evenly; then heat to 90-95℃ and mix for 5-10 min to promote the uniform dispersion of each functional component in the rubber matrix; finally heat to 100-110℃ for final mixing for 5-10 min to initially activate the crosslinking reaction; after mixing, control the Mooney viscosity of the compound to 60-80 MU to obtain a uniform compound. S4. The compounded rubber is extruded through a single-screw extruder with a screw length-to-diameter ratio of 25-30:1. The three-stage temperature control is set as follows: front section 90-100℃, middle section 120-130℃, and rear section 140-150℃. The extrusion rate is 5-15m / min. A continuous rubber strip is formed through the die orifice of the extruder head. S5. Use an underwater pelletizer to pelletize the continuous rubber strip. The pelletizing speed is 300-500 r / min, and the particle size is controlled at 1-5 mm. After pelletizing, immediately send the pellets into a cooling water tank at a water temperature of 20-30℃ for 5-10 minutes to allow the surface of the pellets to solidify and form quickly. S6. After cooling, the granules are placed in a hot air circulating oven for curing. The curing temperature is maintained at 80-100℃ for 8-12 hours. After cooling to room temperature, the granules are sieved to remove fine powder particles with a particle size <1mm and agglomerated particles with a particle size >5mm. Qualified granules with a particle size of 1-5mm are retained to obtain the finished product.

[0012] The beneficial effects of this invention are as follows: The EPDM colored rubber granules of this invention achieve a synergistic combination of weather resistance, hydrophobic self-cleaning properties, and high mechanical performance. Through a specific ratio of weather-resistant masterbatch, fluorosilicone hydrophobic additives, and dynamic crosslinking agents, the limitations of traditional functional separation in modification are overcome. The in-situ formed integrated shell enhances weather resistance and hydrophobic durability. The segmented temperature-controlled process precisely induces the migration of functional components into the shell, balancing dispersion uniformity and structural stability, and requires no post-processing for easy industrialization. These granules exhibit excellent compatibility with raw materials, have a simplified formula without redundant additives, and are suitable for outdoor sports fields, pathways, and other scenarios, effectively ensuring the durability of the product's appearance and service life. Detailed Implementation

[0013] To make the objectives, technical solutions, and advantages of the embodiments of the present invention clearer, the technical solutions in the embodiments of the present invention will be clearly and completely described below in conjunction with the embodiments of the present invention. All other embodiments obtained by those skilled in the art based on the embodiments of the present invention without creative effort are within the scope of protection of the present invention.

[0014] Example 1: This Example 1 describes a high-performance weather-resistant EPDM colored rubber granule, which is prepared from the following raw materials in parts by weight: 68 parts EPDM rubber, 3 parts migratable weather-resistant masterbatch (hindered amine light stabilizer 770: benzophenone-based UV absorber UV-531: polyolefin wax = 1:1:2.5), 0.8 parts dynamic crosslinking agent (N,N'-m-phenylenebismaleimide), 1.5 parts fluorosilicone hydrophobic additive (polytrifluoropropylmethylsiloxane), 4 parts colored pigment (red organic pigment pigment, solid content 50%), 22 parts reinforcing filler (nano silica, particle size 50nm), 1.8 parts environmentally friendly vulcanizing composite component (1 part dicumyl peroxide + 0.8 parts triallyl isocyanurate); The specific preparation steps of a high-performance weather-resistant EPDM colored rubber granule in this embodiment are as follows: S1. Dry the EPDM rubber in a 60℃ oven for 3 hours to remove surface moisture; dry the reinforcing filler in a 115℃ oven for 5 hours, controlling the moisture content to ≤0.5wt%. S2. Weigh all the pretreated raw materials according to the weight parts. First, put the EPDM rubber into the internal mixer. After the rubber softens for 5-8 minutes, add the reinforcing filler, migratable weather-resistant masterbatch, dynamic crosslinking agent, fluorosilicone hydrophobic additive, and color paste in sequence. Finally, add the environmentally friendly vulcanizing composite component. S3. Control the rotor speed of the internal mixer to 60 r / min, with a total mixing time of 21 min. Specifically, premix at 80-85℃ for 8 min to ensure the materials are initially mixed evenly; then heat to 90-95℃ and mix for 7 min to promote the dispersion of each functional component; finally heat to 100-110℃ and finish mixing for 6 min to initially activate the crosslinking reaction; after mixing, the Mooney viscosity (ML1+4, 100℃) of the compound is 70 MU, resulting in a homogeneous compound. S4. The compounded rubber is extruded through a single-screw extruder with a screw length-to-diameter ratio of 28:1. The three-stage temperature control is set as follows: front section 95℃, middle section 125℃, and rear section 145℃. The extrusion rate is 10m / min. A continuous rubber strip is formed through the die head hole, inducing the weather-resistant components and hydrophobic components to migrate to the surface of the rubber strip. S5. Use an underwater pelletizer to pelletize the continuous rubber strip at a speed of 400 r / min and control the particle size to be 2-3 mm. Immediately after pelletizing, send the pellets into a 30℃ cooling water bath and cool for 8 minutes to allow the surface of the pellets to solidify rapidly. S6. Post-curing and sieving: After cooling, the granules are sent into a hot air circulating oven and kept at 90℃ for 10 hours for post-curing. After curing, the granules are cooled to room temperature and sieved using a standard sieve to remove fine powder with a particle size <1mm and agglomerated particles with a particle size >5mm, retaining qualified particles of 2-3mm to obtain the finished product.

[0015] Example 2: This Example 2 describes a high-performance weather-resistant EPDM colored rubber granule, which is prepared from the following raw materials in parts by weight: 68 parts EPDM rubber, 3 parts migratable weather-resistant masterbatch (hindered amine light stabilizer 770: benzophenone-based UV absorber UV-531: polyolefin wax = 1:1:2.5), 0.8 parts dynamic crosslinking agent (N,N'-m-phenylenebismaleimide), 2.2 parts fluorosilicone hydrophobic additive (polytrifluoropropylmethylsiloxane), 4 parts colored pigment (red organic pigment pigment, solid content 50%), 22 parts reinforcing filler (nano silica, particle size 50nm), and 1.8 parts environmentally friendly vulcanizing composite component (1 part dicumyl peroxide + 0.8 parts triallyl isocyanurate). The preparation method of a high-performance weather-resistant EPDM colored rubber granule in this embodiment is the same as that in Example 1, except that the fluorosilicone hydrophobic additive is increased to 2.2 parts.

[0016] Example 3: This Example 3 describes a high-performance weather-resistant EPDM colored rubber granule, which is prepared from the following raw materials in parts by weight: 68 parts EPDM rubber, 3 parts migratable weather-resistant masterbatch (hindered amine light stabilizer 770: benzophenone-based UV absorber UV-531: polyolefin wax = 1:1:2.5), 0.8 parts dynamic crosslinking agent (N,N'-m-phenylenebismaleimide), 2.8 parts fluorosilicone hydrophobic additive (polytrifluoropropylmethylsiloxane), 4 parts colored pigment (red organic pigment pigment, solid content 50%), 22 parts reinforcing filler (nano silica, particle size 50nm), 1.8 parts environmentally friendly vulcanizing composite component (1 part dicumyl peroxide + 0.8 parts triallyl isocyanurate); The preparation method of a high-performance weather-resistant EPDM colored rubber granule in this embodiment is the same as that in Example 1, except that the fluorosilicone hydrophobic additive is increased to 2.8 parts.

[0017] Comparative Example 1: The rubber granules of Comparative Example 1 were prepared from the following parts by weight of raw materials: 68 parts EPDM rubber, 3 parts migratable weather-resistant masterbatch (hindered amine light stabilizer 770: benzophenone-based UV absorber UV-531: polyolefin wax = 1:1:2.5), 1.5 parts fluorosilicone hydrophobic additive (polytrifluoropropylmethylsiloxane), 4 parts colored pigment (red organic pigment pigment, solid content 50%), 22 parts reinforcing filler (nano silica, particle size 50nm), and 1.8 parts environmentally friendly vulcanizing composite component (1 part dicumyl peroxide + 0.8 parts triallyl isocyanurate). The preparation method of the rubber particles in this comparative example is the same as that in Example 1, except that no dynamic crosslinking agent is added.

[0018] Comparative Example 2: The rubber granules of Comparative Example 2 were prepared from the following parts by weight of raw materials: 68 parts EPDM rubber, 3 parts migratable weather-resistant masterbatch (hindered amine light stabilizer 770: benzophenone-based UV absorber UV-531: polyolefin wax = 1:1:2.5), 0.8 parts dynamic crosslinking agent (N,N'-m-phenylenebismaleimide), 4 parts colored pigment (red organic pigment pigment, solid content 50%), 22 parts reinforcing filler (nano silica, particle size 50nm), and 1.8 parts environmentally friendly vulcanizing composite component (1 part dicumyl peroxide + 0.8 parts triallyl isocyanurate). The preparation method of the rubber particles in this comparative example is the same as that in Example 1, except that no fluorosilicone hydrophobic additive is added.

[0019] Performance testing 1. Tensile strength Referring to the national standard GB / T 528-2009, the EPDM colored rubber granules of Examples 1-3 and Comparative Examples 1-2 were mixed with the matching adhesive at a mass ratio of 100:5. The mixture was then molded into dumbbell-shaped Type 1 specimens at 160℃ and 10MPa. The specimens were placed in an environment with constant temperature and humidity of 23℃ and 50% relative humidity for 24 hours. Tensile tests were performed on the specimens using an electronic universal testing machine at a tensile rate of 500mm / min. The maximum tensile force at which the specimen broke was recorded. The tensile strength was calculated based on the cross-sectional area of ​​the effective working section of the specimen. Three parallel specimens were tested in each group, and the average value was taken as the final test result.

[0020] Table 1. Experimental data on tensile strength tests of different samples

[0021] The tensile strength of Examples 1-3 is above 12.8 MPa, with Example 2 reaching 13.5 MPa, demonstrating excellent mechanical properties. Comparative Example 1, without the addition of dynamic crosslinking agent, has a tensile strength of only 8.8 MPa, significantly lower than the examples, confirming that dynamic crosslinking agent can effectively improve the mechanical strength of the material. Fluorosilicone hydrophobic additives have no negative impact on the mechanical properties of the system and have good compatibility.

[0022] 2. QUV aging resistance test The EPDM colored rubber granules from Examples 1-3 and Comparative Examples 1-2 were made into standard samples with a size of 100mm×50mm×2mm and placed in a QUV aging test chamber. The irradiation intensity was set to 0.68W / m2 (340nm), and continuous testing was conducted using a cyclic mode of "8h UV irradiation (60℃) + 4h condensation (50℃)". During the test, the samples were taken out every 200h to observe whether there were phenomena such as powdering, cracking, or discoloration. At the same time, the tensile strength retention rate was tested according to GB / T 528-2009. The test was stopped when the tensile strength of the sample decreased by 30% or obvious powdering occurred. The cumulative aging time was recorded as the evaluation index of QUV aging resistance.

[0023] Table 2. Test data on QUV aging resistance of different samples

[0024] The QUV aging time of Examples 1-3 all exceeded 2500h, with Example 3 reaching 2800h, demonstrating excellent weather resistance. Comparative Example 1 lacked a dynamic crosslinking agent, and Comparative Example 2 did not add fluorosilicone hydrophobic additives, resulting in aging times of 1850h and 2350h, respectively, indicating that the two components worked synergistically to significantly improve the outdoor aging stability of EPDM rubber particles.

[0025] 3. Surface water contact angle The surface water contact angle test was conducted using the seated drop method. EPDM colored rubber granules from Examples 1-3 and Comparative Examples 1-2 were molded into smooth 10mm×10mm×2mm samples. Before testing, the sample surface was wiped with anhydrous ethanol and allowed to air dry naturally. The samples were then placed in an environment of 23℃ and 50% relative humidity for 1 hour to equilibrate. A contact angle measuring instrument was used, with deionized water as the test liquid. Each time, 5μL of water droplets were slowly dropped onto different areas of the sample surface (avoiding edges and defects). The contact angle image was recorded immediately after the droplets fell. Five different measuring points were tested for each group of samples. After removing outliers, the average value was taken as the final surface water contact angle test result.

[0026] Table 3. Water contact angle data for different sample surfaces

[0027] The surface water contact angles of Examples 1-3 all exceeded 110°, increasing to 119° with the increase of fluorosilicone hydrophobic additive dosage, demonstrating excellent hydrophobic effect; Comparative Example 2, without the additive, had a contact angle of only 86° and no obvious hydrophobic function, proving that fluorosilicone hydrophobic additive is the key to giving the product hydrophobic properties.

[0028] 4. Color fastness / color difference after aging test Color fastness and color difference after aging were tested according to GB / T 16422.3-2022 "Laboratory Light Source Exposure Test Methods for Plastics - Part 3: Fluorescent Ultraviolet Lamp" and GB / T 15596-2021 "Determination of Color and Performance Changes of Plastics after Exposure to Solar Radiation, Natural Climate or Laboratory Radiation Sources after Glass Filtering", and graded with reference to GB / T 250-2008 "Textiles - Color Fastness Tests - Assessment of Color Change - Gray Scale". The EPDM colored rubber granules of Examples 1-3 and Comparative Examples 1-2 were made into samples with smooth surfaces. The initial CIE Lab color parameters were first measured with a colorimeter. Then, the samples were placed in a fluorescent ultraviolet aging device to complete the exposure test under standard conditions. After aging, the samples were equilibrated in an environment of 23°C and 50% relative humidity for 2 hours. The color parameters were measured again and the color difference was calculated. Finally, the color fastness grade was assessed with reference to the gray scale. Three parallel samples were tested in each group, and the average value was taken as the final result.

[0029] Table 4. Color fastness / color difference test data of different samples after aging

[0030] After aging, the color difference ΔE of Examples 1-3 was less than 2.0, and the color fastness reached level 7-8, showing outstanding anti-fading performance. Comparative Examples 1 and 2, due to the lack of key components, showed increased color difference and decreased color fastness, indicating that the dynamic crosslinking agent and fluorosilicone hydrophobic additive can synergistically ensure color stability during outdoor use.

[0031] 5. Mooney viscosity Mooney viscosity testing was performed according to GB / T 1232.1-2016 "Determination of unvulcanized rubber using a Mooney viscometer - Part 1: Basic method". The compound rubber samples from Examples 1-3 and Comparative Examples 1-2 were cut into cylindrical specimens approximately 8 mm thick with a diameter slightly larger than the Mooney viscometer rotor. These specimens were preheated in a Mooney viscometer at 100°C for 1 min. The rotor was then started (2 r / min), and timing was initiated. The Mooney viscosity value (ML1+4, 100°C) was recorded after 4 min. Two parallel samples were tested in each group, and the average value was taken as the final Mooney viscosity test result.

[0032] Table 5. Test data of Mooney viscosity for different samples

[0033] The Mooney viscosity of the rubber compounds in Examples 1-3 was between 68-70 MU, which was moderate and stable, indicating that the rubber compounds had good processing performance and the components were evenly dispersed. Although the Mooney viscosity of Comparative Examples 1 and 2 fluctuated slightly, it was within the appropriate processing range and did not affect the subsequent molding process.

[0034] 6. Particle size distribution Particle size distribution testing was conducted according to GB / T 29024.1-2012 "Particle Size Analysis by Laser Diffraction - Part 1: General Rules". The qualified rubber particle samples from Examples 1-3 and Comparative Examples 1-2 were thoroughly mixed after sieving. Approximately 5g of sample was randomly weighed and placed in a beaker containing a small amount of anhydrous ethanol (dispersion medium). The mixture was gently stirred to ensure uniform particle dispersion (avoiding agglomeration). The dispersed sample was then slowly injected into the sample cell of the laser particle size analyzer. The test temperature was set to 23℃, and particle size distribution was measured under suitable shading conditions. The particle size distribution range, D10, D50, and D90 values ​​were recorded. Three parallel samples were tested in each group, and the average value was taken as the final particle size distribution test result.

[0035] Table 6. Particle size distribution data for different samples

[0036] The rubber granules of Examples 1-3 and Comparative Examples 1-2 have a particle size distribution of 1.1-4.9 mm and a median particle size of 2.5-2.8 mm in D50, which meets the preset product specifications. The particle size uniformity is good, with no obvious agglomeration or fine powder accumulation, which can meet the actual application requirements of outdoor laying and molding processing.

[0037] The above embodiments are only used to illustrate the technical solutions of the present invention, and are not intended to limit it. Although the present invention has been described in detail with reference to the foregoing embodiments, those skilled in the art should understand that modifications can still be made to the technical solutions described in the foregoing embodiments, or equivalent substitutions can be made to some of the technical features. Such modifications or substitutions do not cause the essence of the corresponding technical solutions to deviate from the spirit and scope of the technical solutions of the embodiments of the present invention.

Claims

1. A high-performance weather-resistant EPDM colored rubber granule, characterized in that, The rubber granules are prepared from the following raw materials in parts by weight: EPDM rubber 60-75 parts, migratable weather-resistant masterbatch 1.5-6 parts, dynamic crosslinking agent 0.3-2 parts, fluorosilicone hydrophobic additive 0.8-3 parts, colored pigment 2-8 parts, reinforcing filler 15-35 parts, environmentally friendly vulcanizing composite component 0.7-3 parts; The environmentally friendly vulcanizing composite component is a compound of peroxide vulcanizing agent and crosslinking agent; the rubber particles have an in-situ weather-resistant and hydrophobic integrated shell layer formed on their surface, and the particle size is 1-5mm.

2. The high-performance weather-resistant EPDM colored rubber granules according to claim 1, characterized in that, The migratable weather-resistant masterbatch is a compound of hindered amine light stabilizer, benzophenone ultraviolet absorber and polyolefin wax, with a mass ratio of 1:1:2-3.

3. The high-performance weather-resistant EPDM colored rubber granules according to claim 1, characterized in that, The dynamic crosslinking agent is a maleimide-based or disulfide-type dynamic crosslinking agent, selected from N,N'-m-phenylenebismaleimide or dibenzothiazole disulfide.

4. The high-performance weather-resistant EPDM colored rubber granules according to claim 1, characterized in that, The fluorosilicone hydrophobic additive is a fluorinated polysiloxane or a fluorosilane coupling agent, wherein the fluorine content is 15-30 wt%.

5. The high-performance weather-resistant EPDM colored rubber granules according to claim 1, characterized in that, In the environmentally friendly vulcanized composite component, the peroxide vulcanizing agent is selected from one or more of dicumyl peroxide, benzoyl peroxide, and 2,5-dimethyl-2,5-di-tert-butylperoxyhexane; the crosslinking aid is selected from one or more of triallyl isocyanurate, trimethylolpropane triacrylate, and divinylbenzene.

6. The high-performance weather-resistant EPDM colored rubber granules according to claim 1, characterized in that, The reinforcing filler is one or more of nano-silica, carbon black, and calcium carbonate.

7. The high-performance weather-resistant EPDM colored rubber granules according to claim 1, characterized in that, The rubber granules have a QUV aging resistance time of 2000-3000h, a surface water contact angle of 105°-120°, a tensile strength of 10-15MPa, and a color fastness of grade 7-8.

8. A method for preparing high-performance weather-resistant EPDM colored rubber granules, used to prepare the high-performance weather-resistant EPDM colored rubber granules according to any one of claims 1-7, characterized in that, The specific preparation method is as follows: S1. Dry the EPDM rubber in an oven at 60-70℃ for 2-4 hours to remove surface moisture; dry the reinforcing filler at 110-120℃ for 4-6 hours, controlling the moisture content to ≤0.5wt%. S2. Put EPDM rubber into an internal mixer. After the rubber softens for 5-8 minutes, add reinforcing filler, migratable weather-resistant masterbatch, dynamic crosslinking agent, fluorosilicone hydrophobic additive, and color paste in sequence. Finally, add environmentally friendly vulcanizing composite components. S3. Control the rotor speed of the internal mixer to 50-80 r / min, and the total mixing time to 15-30 min. Specifically, premix at 80-85℃ for 5-10 min to make the materials initially mixed evenly; then heat to 90-95℃ and mix for 5-10 min to promote the uniform dispersion of each functional component in the rubber matrix. Finally, the temperature is raised to 100-110℃ for 5-10 minutes to initially activate the crosslinking reaction; after the mixing is completed, the Mooney viscosity of the compound is controlled at 60-80MU to obtain a uniform compound. S4. The compounded rubber is extruded through a single-screw extruder with a screw length-to-diameter ratio of 25-30:

1. The three-stage temperature control is set as follows: front section 90-100℃, middle section 120-130℃, and rear section 140-150℃. The extrusion rate is 5-15m / min. A continuous rubber strip is formed through the die orifice of the extruder head. S5. Use an underwater pelletizer to pelletize the continuous rubber strip. The pelletizing speed is 300-500 r / min, and the particle size is controlled at 1-5 mm. After pelletizing, immediately send the pellets into a cooling water tank at a water temperature of 20-30℃ for 5-10 minutes to allow the surface of the pellets to solidify and form quickly. S6. After cooling, the granules are placed in a hot air circulating oven for curing. The curing temperature is maintained at 80-100℃ for 8-12 hours. After cooling to room temperature, the granules are sieved to remove fine powder particles with a particle size <1mm and agglomerated particles with a particle size >5mm. Qualified granules with a particle size of 1-5mm are retained to obtain the finished product.

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