EPDM: Production route
Solution, slurry or gas phase: three ways to make it
What this tab covers How it is made: the main production routes or, for product families, the main product types and technologies, compared on share of supply, inputs per tonne, plant scale, yield, co-products and unit cost.EPDM is made by copolymerising ethylene and propylene with a diene. The main technologies differ in reactor and catalyst. Solution processes in hexane are the most common. Slurry processes polymerise in liquid propylene. Gas-phase processes avoid solvent. Older plants use vanadium Ziegler-Natta catalysts; newer ones use metallocene or constrained-geometry catalysts (Dow Nordel, Arlanxeo Keltan ACE) that give tighter control and lower energy. Grades are defined by ethylene content, ENB level and Mooney viscosity.
Routes compared
| Route | Share of supply | Inputs per tonne | Typical scale | Yield | Co-products | Unit cost |
|---|---|---|---|---|---|---|
| Solution polymerisation | about 75-80% (indicative) | about 0.6 t ethylene, 0.33 t propylene, 0.07 t ENB (typical grade, indicative) | 50-200 kt/yr lines | over 95% on monomers after recycle (indicative) | none material; solvent recycled | monomer cost about $900/t at late-2025 Asian prices (0.6 x ethylene $700s/t + 0.33 x propylene $700s/t + 0.07 x ENB about $3,000/t, indicative) plus about $400-600/t conversion (indicative) |
| Slurry (suspension) polymerisation | about 10-15% (indicative) | similar monomer ratios (indicative) | 50-100 kt/yr | not published | none | lower energy than solution (indicative) |
| Gas-phase polymerisation | about 5-10% (indicative) | similar, plus carbon black flow aid (indicative) | about 100 kt/yr | not published | none | low energy (indicative) |
How each route works
Solution polymerisationEthylene, propylene and ENB are dissolved in hexane and polymerised with vanadium or metallocene catalysts at moderate pressure. The polymer solution is steam-stripped or devolatilised, then dried and baled. Used by Dow, ExxonMobil, Arlanxeo, Mitsui and Kumho (indicative).
Flexible grades; high steam use for solvent removal.
ethylene and propylene tiles (ChemOrbis Dec 2025); indicative Slurry (suspension) polymerisationMonomers are polymerised in liquid propylene, which acts as both reactant and diluent, removing the need for hexane. Used by Versalis (Dutral) (indicative).
Less energy; narrower grade range.
indicative Gas-phase polymerisationMonomers are polymerised in a fluidised bed with carbon black as a flow aid, giving granular EPDM without solvent. Developed by Union Carbide, now Dow (Nordel MG) (indicative).
No solvent; product contains carbon black.
indicative Unit economics are indicative ranges from the sources named; costs move with feedstock and energy prices, plant size and region.