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EPDM Solid

Grade · default condition

also Ethylene Propylene Diene Monomer, Nordel

Solid = dense vulcanized EPDM compound

Default dense rubber for O-rings, gaskets, weatherstrip and hose where a pressure-tight, load-bearing seal is needed.

Injection moldingStandard cost $$

Values for the Solid condition

Other EPDM grades and fills

EPDM is listed in 12 conditions; see the grade overview at EPDM.

Compare all 12 grades and fillsHide
Grade · open for datasheetBest forYield MPaTensile MPaElong. %Hardness
Closed-cell / open-cell cellular EPDM
Pick for low-closure-force dust, water and acoustic sealing (cabinet gaskets, door seals) where compression load must stay low.220020 Shore A
Shore A 40
Soft grade for low-force conformal sealing on rough or uneven flanges.855040 Shore A
Flame-retardant
Use for rail, cable-accessory and enclosure seals needing UL 94 V-0 or EN 45545 fire performance; ATH loading raises stiffness and cuts elongation.825025 Shore D
Shore A 50
Compromise durometer for low-pressure static gaskets needing good conformability.950050 Shore A
Carbon-black conductive / semiconductive grade
Highly conductive-black loaded compound for cable semicon layers, EMI/static-dissipative gaskets and grounding pads.1025025 Shore D
Shore A 60
General sheet/extrusion durometer balancing sealing force and abrasion life.1145060 Shore A
SolidDefaultThis page
Dense vulcanized EPDM compound
Default dense rubber for O-rings, gaskets, weatherstrip and hose where a pressure-tight, load-bearing seal is needed.1240022 Shore D
Shore A 70
Industry-default hardness for O-rings and dynamic-pressure static seals.1240022 Shore D
Sulfur-cured
Lowest-cost, fastest-curing option for weatherstrip, roofing and general gaskets below ~120 °C.1242022 Shore D
Shore A 80
Use for higher-pressure seals, backup rings and extrusion-resistant profiles.1430030 Shore D
Peroxide-cured
Choose for steam, hot water and 150 °C air service, and wherever low compression set or non-staining/low-extractable behaviour is required.1535022 Shore D
Shore A 90
Rigid rubber for bushings, wheel treads and highly extruded seal geometries.1620038 Shore D

What is EPDM Solid?

EPDM Solid is EPDM in the Solid grade — default dense rubber for O-rings, gaskets, weatherstrip and hose where a pressure-tight, load-bearing seal is needed. EPDM Solid has a tensile strength of 12 MPa (1.74 ksi), weaker than 76% of polymer grades. Elongation at break is 400% and the elastic modulus is 0.01 GPa (8.7×10⁻⁴ Msi). EPDM Solid has a density of 1.15 g/cm³ (0.0415 lb/in³), lighter than 57% of polymer grades. Its glass-transition temperature is -55°C (-67 °F).

Advantages

  • Good UV / weathering resistance — 95/100, better than 95% of polymer grades
  • Forms and bends easily — 90/100, better than 91% of polymer grades
  • Ductile — tolerates forming and impact — 400%, better than 86% of polymer grades
  • Conducts heat well — 0.3 W/m·K (0.173 BTU/hr·ft·°F), better than 83% of polymer grades

Limitations

  • Hard to polish — 20/100, worse than 95% of polymer grades
  • High mold shrinkage — 2.5%, worse than 93% of polymer grades
  • Difficult to machine — 30/100, worse than 87% of polymer grades
  • Low stiffness — 0.01 GPa (8.7×10⁻⁴ Msi), worse than 86% of polymer grades
  • Difficult to weld — 15/100, worse than 78% of polymer grades

EPDM Solid properties

Typical room-temperature values for EPDM Solid; 17 are specific to this condition. Other listed values are EPDM reference data and may not represent this condition. Bars are the position among polymer grades.

Physical3

EPDM Solid has a density of 1.15 g/cm³ (0.0415 lb/in³), lighter than 57% of polymer grades. Its glass-transition temperature is -55°C (-67 °F).

Density1.15 g/cm³0.04 lb/in³
Glass Transition (Tg)-55°C-67 °F
Water Absorption (24 h)0.5%

Mechanical10

EPDM Solid has a tensile strength of 12 MPa (1.74 ksi), weaker than 76% of polymer grades. Elongation at break is 400% and the elastic modulus is 0.01 GPa (8.7×10⁻⁴ Msi).

Elastic (Young's) Modulus0.01 GPa8.7×10⁻⁴ Msi
Shear Modulus0 GPa2.9×10⁻⁴ Msi
Bulk Modulus2 GPa0.29 Msi
Poisson's Ratio0.5
Tensile Strength (Ultimate)12 MPa1.7 ksi
Elongation at Break400%
Hardness, Shore A70 Shore A
Hardness, Shore D22 Shore D
Tear Strength25 kN/m143 lbf/in
Compression Set (22 h, 70 °C)20%

Thermal8

EPDM Solid is rated for continuous service to 120°C (248 °F). It conducts heat at 0.3 W/m·K (0.173 BTU/hr·ft·°F), better than 83% of polymer grades. Thermal expansion is 180 µm/m·K (100 µin/in·°F).

Thermal Conductivity0.3 W/m·K0.17 BTU/hr·ft·°F
Specific Heat Capacity2,000 J/kg·K0.48 BTU/lb·°F
Thermal Expansion (CTE, 20–100 °C)180 µm/m·K100 µin/in·°F
Max Service Temperature (continuous)120°C248 °F
Min Service Temperature-50°C-58 °F
Flammability (UL 94)HB (burns; only FR-compounded grades reach V-0)
Limiting Oxygen Index19%
Max Service Temperature (short-term)160°C320 °F

Electrical6

EPDM Solid is an electrical insulator with a dielectric strength of 25 kV/mm (635 V/mil) and a resistivity of 1×10¹² Ω·m.

Electrical Resistivity1×10¹² Ω·m3.94×10¹⁹ µΩ·in
Dielectric Strength25 kV/mm635 V/mil
Dielectric Constant (1 MHz)3
Dissipation Factor (1 MHz)0.007
Volume Resistivity1×10¹⁴ Ω·cm
Comparative Tracking Index (CTI)600 V

Chemical & Environmental3

Corrosion resistance is excellent (85/100), better than 65% of polymer grades. UV resistance is excellent.

Corrosion ResistanceExcellent85/100
UV / Weathering ResistanceExcellent95/100
Chemical Resistance SummaryExcellent in water, steam, dilute acids/alkalis, ozone, ketones, glycol brake fluid and outdoor weathering; poor in mineral oil, grease, fuels, aromatic and chlorinated solvents (large swell).

Sustainability4

Producing a kilogram of EPDM Solid takes about 95 MJ of energy and emits 4 kg of CO₂ — less than 70% of polymer grades. Typical recycled content is 5%.

Embodied Energy (primary production)95 MJ/kg40,843 BTU/lb
Embodied Carbon (primary production)4 kg CO₂/kg
Embodied Water150 L/kg18 gal/lb
Typical Recycled Content5%

Manufacturability7

EPDM Solid's machinability is poor (30/100, worse than 87% of polymer grades); weldability poor (15/100); formability excellent (90/100).

MachinabilityPoor30/100
WeldabilityPoor15/100
Formability (cold)Excellent90/100
PolishabilityPoor20/100
Mold Shrinkage2.5%
Processing Melt Temperature (typ.)100°C212 °F
Mold Temperature (typ.)175°C347 °F

Common Calculations4

Specific Strength (UTS / density)calculated10 kN·m/kg
Specific Stiffness (E / density)calculated0 MN·m/kg
Thermal Diffusivitycalculated0.1 mm²/s
Thermal Shock Resistance Indexcalculated3

Values are nominal handbook figures for design screening. Confirm any required mill or lot documentation when quoting.

Working with EPDM Solid

Is EPDM easy to machine?

Best die-cut, waterjet or knife/CNC-blade cut with soap lubricant; milling and drilling smear and tear unless the part is frozen or a sharp hollow punch is used.

Can EPDM be welded?

Not thermally weldable — join by hot vulcanized splice, uncured tape splice, or cyanoacrylate/CR contact adhesive after abrasion plus primer.

Can EPDM be formed, bent or molded?

Mix on internal mixer/two-roll mill, then extrude profiles or compression/transfer/injection mold and vulcanize ~160–200 °C; sponge grades use chemical blowing agents with a matched slow cure.

What surface finishes work on EPDM?

Surface finish comes from the mold or extrusion die; flash removed by cryogenic deflashing, and paintability/bondability requires corona, plasma or chlorination pretreatment.

EPDM chemical composition (wt %)

Limits by weight percent from the governing specification, written the way the spec states them — a single maximum for impurities, a range for alloying elements, and the base element as balance. Nominal is the typical mid-range value.

ElementSpec limit (wt %)Nominal
ethylene (C2 units)polymer C2 content; high-C2 grades are semi-crystalline45 – 7560
ENB diene (5-ethylidene-2-norbornene)cure site for sulfur vulcanization; DCPD/VNB used in some grades0.5 – 125
carbon black (N550/N660)phr on polymer, in the compounded rubber20 – 9060
paraffinic process oilphr; oil-extended polymers supplied pre-oiled10 – 10050
calcium carbonate / clay fillerphr, cost filler0 – 8030
zinc oxide + stearic acidphr, activators≈ 66
sulfur + accelerators or organic peroxidphr, cure system1 – 83
propylene (C3 units)balance of polymer backbone≥ 20 (balance)

EPDM Solid — frequently asked

What is EPDM Solid used for?

EPDM Solid is typically used for automotive window and door weatherstrip, roofing membranes, steam and hot-water gaskets, coolant and radiator hoses, sponge sealing profiles for enclosures and HVAC duct and access-panel gaskets. In short: weatherproof rubber.

What is the tensile strength of EPDM Solid?

EPDM Solid has a typical tensile strength of 12 MPa (1.74 ksi) — weaker than 76% of polymer grades. Strength varies by condition: see the 12 listed tempers.

Is EPDM Solid easy to machine?

Not especially — machinability is rated poor (30/100, worse than 87% of polymer grades). Best die-cut, waterjet or knife/CNC-blade cut with soap lubricant; milling and drilling smear and tear unless the part is frozen or a sharp hollow punch is used.

Can EPDM Solid be welded?

Not readily — weldability is rated poor (15/100). Not thermally weldable — join by hot vulcanized splice, uncured tape splice, or cyanoacrylate/CR contact adhesive after abrasion plus primer.

What surface finishes work on EPDM Solid?

Surface finish comes from the mold or extrusion die; flash removed by cryogenic deflashing, and paintability/bondability requires corona, plasma or chlorination pretreatment.

Can EPDM Solid be formed, bent or molded?

Mix on internal mixer/two-roll mill, then extrude profiles or compression/transfer/injection mold and vulcanize ~160–200 °C; sponge grades use chemical blowing agents with a matched slow cure.

What is the maximum service temperature of EPDM Solid?

EPDM Solid is rated for continuous use to about 120°C (248 °F), and briefly to 160°C. Strength falls off well before that limit — check the elevated-temperature data for load-bearing parts.

Can FabDigit make parts in EPDM Solid?

Yes — EPDM Solid is available for injection molding; every part is priced by an engineer rather than instantly. Upload a STEP file to get a price and a DFM check.

Sources

  1. ASTM D2000 — Rubber Products in Automotive Applications (classification AA/BA/CA/DA lines) — ASTM (2023)
  2. ASTM D1418 — Rubber and Rubber Latices Nomenclature (EPDM) — ASTM (2022)
  3. Vistalon EPDM grade and compound data — ExxonMobil Chemical (2023)
  4. Nordel IP EPDM technical information — Dow (2022)
  5. Keltan EPDM compounding guides — Arlanxeo (2023)
  6. ASM Engineered Materials Handbook Vol. 2 — Engineering Plastics/Elastomers — ASM International (1988)
  7. O-ring and elastomer chemical compatibility / property tables — Parker Hannifin O-Ring Handbook (2021)

Property data is compiled from published supplier and standards handbooks and normalised for comparison. Nothing on this page is a certification — request mill certs, CoC or material test reports with your order.