Views: 0 Author: Site Editor Publish Time: 2026-05-18 Origin: Site
EPDM (Ethylene Propylene Diene Monomer) is a terpolymer of ethylene, propylene and diene monomers, belonging to the family of saturated polyolefin elastomers. EPDM granules are granular products obtained by mixing EPDM rubber with fillers, processing oils, pigments and vulcanizing agents, followed by vulcanization, granulation and screening. Unlike ordinary recycled rubber granules (such as SBR), EPDM granules have a saturated molecular backbone, which endows them with outstanding resistance to ozone, UV radiation, high temperature and aging, making them the preferred material for high‑end outdoor surfacing systems.
In recent years, with the rapid development of global sports infrastructure and the increasing emphasis on the safety and durability of recreational facilities, the market demand for EPDM granules has continued to grow. They are not only widely used in traditional sports fields such as running tracks, basketball courts and tennis courts, but also in playgrounds, park paths, industrial anti‑slip flooring and construction joint sealing, showing broad application prospects.
EPDM granules are essentially rubber compounds, and their main components include:
EPDM Rubber (20%–60%): The base polymer, which provides elasticity, weathering resistance and cross‑linking ability. The higher the EPDM content, the better the performance, but the higher the cost.
Fillers (30%–50%): Mainly calcium carbonate, talc, silica, etc., used to reduce cost, adjust hardness and improve processability.
Processing Oils (5%–15%): Such as paraffin oil, naphthenic oil, to improve the flexibility and processability of the rubber compound.
Vulcanizing Agents & Accelerators (1%–5%): Such as sulfur, zinc oxide, stearic acid, to form a cross‑linked network and fix the elastic properties.
UV Stabilizers & Antioxidants (0.5%–2%): To enhance weathering resistance and delay aging.
Color Pigments (1%–3%): Inorganic pigments (such as iron oxide) or organic pigments, with UV‑stable properties to ensure long‑term color fastness.
The production of EPDM granules follows a strict process flow:
Raw Material Weighing: Accurately weigh EPDM rubber, fillers, oils and additives according to the formula.
Internal Mixing: Mix the raw materials in an internal mixer at high temperature (100–120°C) to form a uniform rubber compound.
Open Mixing & Extrusion: Further plasticize the rubber compound in an open mill, then extrude it into strips or sheets.
Vulcanization: Heat and vulcanize the extruded product (140–160°C) to form a cross‑linked rubber structure.
Granulation & Screening: Cut the vulcanized rubber into granules, then screen them into different particle sizes (0.5–4 mm) according to application requirements.
Quality Inspection: Test the granules for EPDM content, hardness, tensile strength, elongation at break and color fastness to ensure compliance with standards.
The saturated molecular backbone of EPDM makes it highly resistant to ozone and UV radiation. It can be used outdoors for a long time (more than 8–10 years) without cracking, hardening or fading, and can withstand extreme temperatures (‑40°C to 120°C). In contrast, SBR granules are prone to aging and cracking after 2–3 years of outdoor use.
EPDM granules have good elasticity (rebound rate ≥ 60%) and shock absorption performance. When used in playgrounds, they can effectively reduce the risk of falls and injuries (meeting EN 1177 and ASTM F1292 standards for critical fall height); in sports fields, they can buffer the impact of athletes’ joints and improve sports comfort.
High‑quality EPDM granules use UV‑stable pigments, with minimal color fade after long‑term outdoor use. They are available in a wide range of colors (red, green, blue, yellow, black, etc.), which can be customized according to design requirements, and are suitable for creative pavement patterns and safety marking divisions.
Qualified EPDM granules are free of harmful substances such as heavy metals and volatile organic compounds (VOCs), meeting EU REACH and US FDA standards. They are non‑irritating to human skin and respiratory tract, and will not cause pollution to soil and water bodies. In addition, waste EPDM granules can be recycled and reused, which is in line with the concept of circular economy.
EPDM granules have a porous structure with good water permeability, which can quickly drain rainwater and avoid water accumulation on the surface. The rough surface of the granules provides excellent anti‑slip performance, ensuring safe use in rainy days or wet environments.
Running Tracks: Mixed or composite tracks made of EPDM granules have good elasticity and anti‑slip performance, meeting IAAF standards.
Basketball/Tennis Courts: EPDM court surfaces are wear‑resistant, anti‑slip and shock‑absorbent, with a service life of more than 8 years.
Artificial Turf Infill: EPDM granules (1–3 mm) are used as infill for artificial turf, which can stabilize the turf fibers, provide elasticity and improve the sports experience.
EPDM granules are the mainstream material for safety flooring in playgrounds, kindergartens and community recreational areas. The cushioning performance can be adjusted according to the fall height (100–300 mm thickness), effectively reducing the risk of children’s falls and injuries. The rich colors can create a colorful and safe recreational environment.
Anti‑Slip Flooring: Used in factory workshops, warehouses, parking lots and ramps to provide anti‑slip and wear‑resistant surfaces.
Sound‑Absorbing Flooring: The porous structure can absorb noise, suitable for recording studios, gymnasiums and multi‑purpose halls.
Corrosion‑Resistant Flooring: Resistant to acid, alkali and oil, suitable for chemical plants, food processing plants and other environments.
Joint Sealing: EPDM granules are used for sealing expansion joints in roads, bridges and buildings, with good elasticity and aging resistance.
Waterproofing Layer: Used as a waterproofing and drainage layer in roof gardens, underground garages and tunnels.
To ensure the performance of EPDM granules, the following key indicators need to be strictly controlled:
EPDM Content: The core indicator, high‑grade products ≥ 25%, medium‑grade 15%–25%, low‑grade < 15% (easy to age).
Particle Size: Common specifications 0.5–1.5 mm (surface layer), 2–4 mm (base layer), with uniform particle size and no impurities.
Hardness: Shore A 50–70 (adjustable according to application).
Tensile Strength: ≥ 3.0 MPa, elongation at break ≥ 300%.
Weathering Resistance: After 5000 hours of UV aging test, the color change grade ≥ 4, no cracking or hardening.
Heavy Metal Content: Lead < 100 mg/kg, cadmium < 10 mg/kg, meeting environmental protection standards.
EPDM granules, as a high‑performance synthetic rubber material, have irreplaceable advantages in weathering resistance, elasticity, safety and environmental protection. With the continuous improvement of global safety standards and the acceleration of urbanization, the application scope of EPDM granules will be further expanded, and the market prospect is broad.
In the future, the development of EPDM granules will focus on the following directions:
High Performance and Low Cost: Develop new EPDM compound formulas, reduce the cost of high‑EPDM‑content products, and improve cost‑effectiveness.
Functionalization: Develop flame‑retardant, antibacterial, conductive and other functional EPDM granules to meet the needs of special scenarios.
Sustainability: Increase the proportion of recycled EPDM rubber, develop bio‑based EPDM materials, and reduce carbon emissions in the production process.
Standardization: Unify the quality standards and testing methods of EPDM granules globally, and standardize the market order.
In summary, EPDM granules will continue to be the preferred material for high‑end surfacing systems, contributing to the construction of safer, more comfortable and sustainable sports and living environments.
