EPDM Rubber
The weather- and ozone-resistant synthetic rubber behind single-ply roofing membranes — and the standard elastomer for automotive seals, gaskets and weatherstripping worldwide.
Chelora Chemicals supplies EPDM to roofing-membrane, automotive-sealing and extrusion manufacturers worldwide, with full documentation and consistent polymer quality on every consignment.
Product identity
- CAS Number
- 25038-36-2
- Polymer type
- Ethylene-propylene-diene terpolymer
- Common dienes
- ENB, DCPD, VNB
- Density
- ~0.86 g/cm³
- Service temperature
- -50 °C to 150 °C
- Physical form
- Solid bales / crumb
- UN Number
- Not regulated*
- HS Code
- 4002 70
* Solid EPDM is not classified as dangerous goods under standard conditions; confirm classification for any compounded or solvent-bearing grades with your regulatory affairs team.
What EPDM Rubber is used for
EPDM Rubber (Ethylene Propylene Diene Monomer rubber) is a solid, weather-resistant synthetic rubber — a terpolymer of ethylene, propylene and a small amount of a diene monomer that provides sites for sulphur vulcanisation. Supplied as bales or crumb, it is compounded with fillers, oils and curatives before processing.
EPDM's single largest use is in single-ply roofing membranes, where its ozone, UV and weathering resistance give decades of outdoor service life. Its second major use is across the automotive industry — door, window, trunk and engine-bay seals, gaskets, and weatherstripping, where its stability across a wide temperature range and resistance to ageing outperform general-purpose rubbers. EPDM is also widely used in hoses, belts, cable and wire insulation, and building seals and gaskets.
Where it sits in the elastomer value chain
- Ethylene & Propylene the olefin feedstocks EPDM is polymerised from.
- EPDM Rubber (this product) the terpolymer base resin supplied to compounders and converters.
- Compounded EPDM the filled, cured end product (roofing sheet, moulded seal, extruded profile) made by the converter.
Handling character
EPDM is a solid, low-hazard elastomer under normal storage and handling. Full hazard detail is in the Safety section below.
| Parameter | Typical value |
|---|---|
| Appearance | Solid bales or crumb, off-white to tan |
| Ethylene content | 45-70% (grade-dependent) |
| Diene content | 2-12% (grade-dependent) |
| Mooney viscosity | Within producer specification |
Important: the figures above are indicative of commercial material and are offered for planning only. The batch certificate of analysis is the governing document.
| Property | Value |
|---|---|
| Physical state | Solid elastomer (bales/crumb) |
| Density | ~0.86 g/cm³ |
| Service temperature | -50 °C to 150 °C |
| Ozone resistance | Excellent |
| Water/steam resistance | Very good |
| Oil/fuel resistance | Poor (use nitrile grades instead) |
Physical constants compiled from public reference data for CAS 25038-36-2 and rounded for readability. Treat them as orientation, not as a specification.
Where our customers put this rubber to work
The elastomer the roofing and automotive sealing industries are built on.
Single-ply roofing membranes
The standard elastomer for large-format weatherproof roofing sheet with decades of outdoor service life.
- Roofing-grade specification
- Bulk & bale supply
- Technical desk review on request
Automotive seals & gaskets
Door, window, trunk and engine-bay seals and gaskets exposed to weather, ozone and temperature swings.
- Automotive-grade specification
- Documented batch traceability
- Contract & spot supply
Weatherstripping & building seals
Door and window weatherstripping, glazing seals and expansion-joint gaskets in construction.
- Packs sized to customer volumes
- Full analytical documentation available
- Retained sample held against the lot
Hoses & belts
Radiator, coolant and industrial hoses, plus belting exposed to heat, steam and weathering.
- Documented batch traceability
- Technical desk review on request
Cable & wire insulation
Jacketing and insulation for outdoor and weather-exposed electrical cable.
- Research & process-scale quantities
- Full documentation supplied
Contract & scheduled supply
Roofing and automotive converters running continuous consumption are supported with scheduled bulk delivery.
- Annual contracts with scheduled call-off
- Price held across the contract period
- Second source held in reserve
How we supply EPDM Rubber
Chelora Chemicals is a supplier and sourcing partner, not a manufacturer. Ethylene/propylene ratio and diene content are critical to compounding and cure behaviour — that shapes how we manage this line.
We place your order with whichever qualified producer best matches your required grade, your price point and your delivery window, and confirm your jurisdiction's import requirements before booking.
We keep a second qualified source on this line, so a single-plant disruption never becomes your production problem.
- Mooney viscosity and diene content confirmed before we quote. Consistency matters to downstream compounding and cure.
- Transport documentation managed end to end. Classification, labelling and carrier compliance confirmed before booking.
- Scheduled call-off scheduling. We hold contracted tonnage and release it against your consumption calendar.
- Batch traceability to the producing plant. Full chain of custody documentation on request.
- Export machinery handled in-house. Classification, approved packing, labelling, freight booking and customs paperwork are ours to manage.
- Roofing-grade and automotive-grade both sourced. Matched precisely to your compounding and cure system.
Packed the way your plant receives it
Bale or bulk bag — tell us your preferred format and we will quote and classify to it.
25-35 kg polywrapped bales
Palletised, shrink-wrapped bales for smaller-volume orders and trial quantities.
~500-1,000 kg crumb/granulate bags
FIBC bulk bags for crumb or granulated grades sized for mid-volume compounder orders.
Full-container-load shipment
Palletised bale loads in standard containers for continuous-consumption compounding plants.
Incoterms to suit you
Quoted on the Incoterm your purchasing team works to, with documentation filed before booking.
Trial / sample quantities
Small packs dispatched for process trials before a commercial order is placed.
Contracted call-off supply
We hold contracted tonnage and release it against your consumption calendar.
A low-hazard solid elastomer — handled with standard care
Solid EPDM bales and crumb are not classified as hazardous under normal conditions. The summary below is orientation only — the safety data sheet supplied with your specific batch is the authoritative document.
Processing hazards to manage
DustNuisance dust from crumb/granulate handling; use standard dust controls.FumesVulcanisation and processing fumes require adequate ventilation.
Low intrinsic hazard, standard industrial hygiene applies. Always read the SDS issued with your specific batch and compound for complete handling guidance.
Storage
Store bales and crumb in a cool, dry area away from direct sunlight and ozone sources (e.g. electrical equipment, welding) to avoid pre-cure surface degradation.
Handling
Use standard PPE (gloves, dust protection) for bale and crumb handling. Provide local exhaust ventilation at compounding, extrusion and vulcanisation stations.
Transport
Solid EPDM is generally not regulated as dangerous goods. We confirm and document classification for any compounded, oil-extended or solvent-bearing grade specific to your shipment.
Every batch, documented
We verify documentation before dispatch so there are no surprises at your incoming-goods bench.
Specification agreed
Ethylene content, diene type and Mooney viscosity confirmed against your compound before order placement.
Producer batch testing
The producing plant tests each batch against the agreed specification before release.
Documentation review
COA, SDS and transport paperwork checked by our desk before the shipment is booked.
Traceable dispatch
Each shipment is traceable to its producing batch, with full chain-of-custody records on request.
How EPDM is made
EPDM is produced industrially by the catalytic terpolymerisation of ethylene, propylene and a diene monomer (commonly ENB, DCPD or VNB), a long-established route in elastomer chemistry. The diene provides unsaturation pendant to the main chain, allowing conventional sulphur vulcanisation while the saturated backbone gives its weathering resistance.
We do not publish operating process parameters here; this is background only. Full technical documentation accompanies every shipment, and any process-specific detail you need is best confirmed directly with our technical desk.
| Chemical family | Saturated olefin terpolymer |
|---|---|
| Functional groups | Pendant unsaturation from diene termonomer |
| Reactivity | Sulphur or peroxide vulcanisation at diene sites |
| Related compounds | Ethylene, Propylene (feedstocks), Nitrile Rubber, Butyl Rubber (related elastomers) |
Explore the wider elastomer range
EPDM Rubber, answered
What is EPDM Rubber used for?
Why is EPDM preferred for outdoor and weather-exposed parts?
Is EPDM Rubber hazardous?
What grade do you supply?
What packing do you offer?
Do you manufacture this yourself?
- Need a related elastomer? See our Nitrile Rubber and Butyl Rubber pages.
Get a quote on EPDM Rubber today
Send us your required grade, pack size and delivery window. We will come back with a firm quote, lead time and full documentation.