ECO GECO
Grade
also Hydrin
GECO = gECO / ETER
Use where sulfur or peroxide cure, lower compression set and the best low-temperature flexibility are required.
Values for the GECO condition
Other ECO grades and fills
ECO is listed in 9 conditions; see the grade overview at ECO.
Compare all 9 grades and fillsHide
| Grade · open for datasheet | Best for | Yield MPa | Tensile MPa | Elong. % | Hardness |
|---|---|---|---|---|---|
Shore A 50 | Soft diaphragms, bellows and low-clamp-force gaskets. | — | 9 | 400 | 12 Shore D |
Conductive / antistatic grade | Choose for fuel hose liners that must dissipate static charge per SAE J30/J2260 requirements. | — | 10 | 220 | 23 Shore D |
GECOThis page GECO / ETER | Use where sulfur or peroxide cure, lower compression set and the best low-temperature flexibility are required. | — | 11 | 280 | 18 Shore D |
Shore A 60 | Hose inner liners and flexible fuel-system components. | — | 11 | 320 | 16 Shore D |
Peroxide-cured GECO compound | Pick for static seals needing low compression set and no lead/thiourea cure residues. | — | 11 | 230 | 22 Shore D |
ECO-CODefault ECO | Standard choice for fuel and vacuum hose, diaphragms and seals needing oil resistance plus −40 °C flexibility. | — | 12 | 250 | 22 Shore D |
Shore A 70 | Default seal/O-ring and hose hardness; best balance of strength and set. | — | 12 | 250 | 22 Shore D |
Epichlorohydrin homopolymer | Pick when the lowest gas/fuel permeability and best hydrocarbon resistance matter more than cold flexibility. | — | 13 | 220 | 22 Shore D |
Shore A 80 | Higher-pressure seals, backup rings and stiff mount elements. | — | 13 | 180 | 30 Shore D |
What is ECO GECO?
ECO GECO is ECO in the GECO grade — use where sulfur or peroxide cure, lower compression set and the best low-temperature flexibility are required. ECO GECO has a tensile strength of 11 MPa (1.6 ksi), weaker than 78% of polymer grades. Elongation at break is 280% and the elastic modulus is 0.01 GPa (7.25×10⁻⁴ Msi). ECO GECO has a density of 1.3 g/cm³ (0.047 lb/in³), heavier than 69% of polymer grades. Its glass-transition temperature is -45°C (-49 °F). ECO-CO is the default condition FabDigit quotes; GECO is available on request or by drawing note.
Advantages
- Good UV / weathering resistance — 88/100, better than 90% of polymer grades
- Forms and bends easily — 88/100, better than 85% of polymer grades
- Ductile — tolerates forming and impact — 280%, better than 80% of polymer grades
- High service temperature — 135°C (275 °F), better than 75% of polymer grades
Limitations
- Difficult to machine — 25/100, worse than 93% of polymer grades
- Absorbs moisture — dry before molding — 1.5%, worse than 91% of polymer grades
- Low stiffness — 0.01 GPa (7.25×10⁻⁴ Msi), worse than 89% of polymer grades
- High mold shrinkage — 2.4%, worse than 89% of polymer grades
- Difficult to weld — 15/100, worse than 78% of polymer grades
ECO GECO properties
Typical room-temperature values for ECO GECO; 19 are specific to this condition. Other listed values are ECO reference data and may not represent this condition. Bars are the position among polymer grades.
Physical4
ECO GECO has a density of 1.3 g/cm³ (0.047 lb/in³), heavier than 69% of polymer grades. Its glass-transition temperature is -45°C (-49 °F).
Mechanical8
ECO GECO has a tensile strength of 11 MPa (1.6 ksi), weaker than 78% of polymer grades. Elongation at break is 280% and the elastic modulus is 0.01 GPa (7.25×10⁻⁴ Msi).
Thermal8
ECO GECO is rated for continuous service to 135°C (275 °F). It conducts heat at 0.21 W/m·K (0.121 BTU/hr·ft·°F), better than 55% of polymer grades. Thermal expansion is 180 µm/m·K (100 µin/in·°F).
Electrical4
ECO GECO is an electrical insulator with a dielectric strength of 16 kV/mm (406.4 V/mil) and a resistivity of 3×10⁷ Ω·m.
Chemical & Environmental3
Corrosion resistance is very good (76/100), worse than 64% of polymer grades. UV resistance is excellent.
Sustainability3
Producing a kilogram of ECO GECO takes about 115 MJ of energy and emits 4.8 kg of CO₂ — more than 70% of polymer grades. Typical recycled content is 0%.
Manufacturability5
ECO GECO's machinability is poor (25/100, worse than 93% of polymer grades); weldability poor (15/100); formability excellent (88/100).
Values are nominal handbook figures for design screening. Confirm any required mill or lot documentation when quoting.
Working with ECO GECO
Is ECO easy to machine?
Cured ECO is best die-cut, water-jet or cryo-deflashed; grinding/turning needs sharp tools and freezing to avoid tearing and smearing.
Can ECO be welded?
Not weldable as a thermoset; joints are made by adhesive bonding (cyanoacrylate/epoxy on chlorinated-primer or plasma-treated surfaces) or by co-vulcanization during molding.
Can ECO be formed, bent or molded?
Mills and extrudes easily but is tacky and scorch-sensitive; compression/injection cure at 160–190 °C with an MgO-type acid acceptor, and post-cure 2–4 h at 150 °C for lowest compression set.
What surface finishes work on ECO?
Usually used as-molded in black; surfaces can be talc- or PTFE-dusted, plasma- or chlorine-treated for low friction, and adhesion to brass/steel inserts is achieved with standard rubber-to-metal bonding agents.
ECO 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.
| Element | Spec limit (wt %) | Nominal |
|---|---|---|
| epichlorohydrin (ECH) unitschlorine-bearing repeat unit; ~30–38 wt% Cl in CO homopolymer | 55 – 75 | 68 |
| ethylene oxide (EO) unitsraises low-temperature flexibility, absent in CO homopolymer | 25 – 45 | 32 |
| allyl glycidyl ether (AGE)cure-site monomer, present only in GECO/ETER terpolymer | 0 – 8 | 0 |
| carbon black (N550/N774)phr in a typical 70 Shore A compound | 30 – 70 | 50 |
| plasticizer / process oil (ether-ester tphr | 0 – 20 | 8 |
| acid acceptor (MgO / hydrotalcite) + curphr; acid acceptor essential to trap evolved HCl | 3 – 10 | 6 |
ECO GECO — frequently asked
What is ECO GECO used for?
ECO GECO is typically used for fuel hoses, vacuum hoses, automotive seals and low-temp gaskets. In short: fuel resistance to -40 °C; inherently antistatic elastomer; low permeability to fuels.
What is the tensile strength of ECO GECO?
ECO GECO has a typical tensile strength of 11 MPa (1.6 ksi) — weaker than 78% of polymer grades. Strength varies by condition: see the 9 listed tempers.
Is ECO GECO easy to machine?
Not especially — machinability is rated poor (25/100, worse than 93% of polymer grades). Cured ECO is best die-cut, water-jet or cryo-deflashed; grinding/turning needs sharp tools and freezing to avoid tearing and smearing.
Can ECO GECO be welded?
Not readily — weldability is rated poor (15/100). Not weldable as a thermoset; joints are made by adhesive bonding (cyanoacrylate/epoxy on chlorinated-primer or plasma-treated surfaces) or by co-vulcanization during molding.
What surface finishes work on ECO GECO?
Usually used as-molded in black; surfaces can be talc- or PTFE-dusted, plasma- or chlorine-treated for low friction, and adhesion to brass/steel inserts is achieved with standard rubber-to-metal bonding agents.
Can ECO GECO be formed, bent or molded?
Mills and extrudes easily but is tacky and scorch-sensitive; compression/injection cure at 160–190 °C with an MgO-type acid acceptor, and post-cure 2–4 h at 150 °C for lowest compression set.
What is the maximum service temperature of ECO GECO?
ECO GECO is rated for continuous use to about 135°C (275 °F), and briefly to 150°C. Strength falls off well before that limit — check the elevated-temperature data for load-bearing parts.
Sources
- Hydrin CO/ECO/ETER epichlorohydrin elastomer technical bulletins — Zeon Chemicals (2021)
- Engineered Materials Handbook Vol.2: Engineering Plastics / Rubber Products Manufacturing Technology — ASM International (1988)
- ASTM D2000 — Classification System for Rubber Products in Automotive Applications (type/class CH, CE) — ASTM (2020)
- ISO 1629 — Rubber and latices: nomenclature (CO, ECO, GECO) — ISO (2013)
- SAE J30 / SAE J2260 — Fuel and vapour hose requirements — SAE International (2018)
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.