EPDM (Ethylene Propylene Diene Rubber) vs PEI (Ultem): 0% composition overlap. Significantly different materials serving different application areas.
EPDM (Ethylene Propylene Diene Rubber) vs PEI (Ultem)
Side-by-side chemical composition and mechanical property comparison.
Overview
EPDM (Ethylene Propylene Diene Rubber)
Ethylene propylene diene monomer rubber — THE outdoor/weather elastomer. Saturated backbone gives outstanding ozone, UV, and weathering resistance. Excellent resistance to steam, hot water, and polar solvents. NOT resistant to oils/fuels (opposite of NBR). Good electrical insulation. ρ 0.85-1.3 (lightest common rubber). Used for automotive door/window seals, roofing membranes, radiator hoses, HVAC gaskets, and pond liners.
PEI (Ultem)
Polyetherimide — high-performance amorphous thermoplastic. Similar properties to PEEK at lower cost but lower impact strength and use temp. Transparent amber color. Tg 217°C, inherent flame resistance (UL94 V-0 at 0.4mm), very low smoke. Hydrolytically stable (2000+ autoclave cycles). Trade name Ultem (SABIC). Used for aerospace interior panels, medical sterilizable devices, electrical insulators, semiconductor handling, and 3D-print build plates.
| EPDM (Ethylene Propylene Diene Rubber) | PEI (Ultem) | |
|---|---|---|
| Material Number | — | — |
| Category | Polymers | Polymers |
| Standard | ISO 37 | ISO 10350 |
Mechanical properties
| Property | EPDM (Ethylene Propylene Diene Rubber) | PEI (Ultem) | Unit |
|---|---|---|---|
| tensile_strength | 7–21 | 85–105 | MPa |
| elongation | 100–700 | 50–60 | % |
| hardness_shore_a | 30–90 | — | Shore A |
Compatibility Assessment
EPDM (Ethylene Propylene Diene Rubber) and PEI (Ultem) have significantly different compositions (0% overlap). These materials are not interchangeable and serve different application areas.
Automated assessment based on composition analysis
Frequently Asked Questions
Is EPDM (Ethylene Propylene Diene Rubber) the same as PEI (Ultem)?
EPDM (Ethylene Propylene Diene Rubber) and PEI (Ultem) have a 0% composition overlap. They are generally not directly interchangeable.
Can I replace EPDM (Ethylene Propylene Diene Rubber) with PEI (Ultem)?
Generally not recommended. The compositions differ significantly (0% overlap). These materials have different alloying concepts and are intended for different applications.
What is the difference between EPDM (Ethylene Propylene Diene Rubber) and PEI (Ultem)?
The main differences are in the following elements: overall alloying content. EPDM (Ethylene Propylene Diene Rubber) is a Polymers grade, while PEI (Ultem) is a Polymers grade.
Related Comparisons
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Data provided for reference only. Always verify against the applicable specification for critical applications.
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