Material Comparison
Compare verified engineering materials side by side with condition-specific mechanical properties.
| Parameter | Silicone Rubber (VMQ) | Ethylene Propylene Diene Rubber (EPDM) |
|---|---|---|
| Material Family | Rubber & Elastomers | Rubber & Elastomers |
| Subfamily | High-Temperature & Specialty Elastomers | Weathering & Chemical Resistant Elastomers |
| ASTM Designation | VMQ | EPDM |
| ISO Designation | VMQ | EPDM |
| ASTM-D2000 Designation | Type FC / FE / GE | Type BA / CA |
| Element | Silicone Rubber (VMQ) | Ethylene Propylene Diene Rubber (EPDM) |
|---|
| Mechanical Parameter | Silicone Rubber (VMQ)Platinum-Cured Liquid Silicone Rubber (Post-Cured 4h at 200°C) | Ethylene Propylene Diene Rubber (EPDM)Peroxide-Cured High-Temperature Compound |
|---|---|---|
| Compression Set (22h at 150°C) · Platinum-Cured Liquid Silicone Rubber (Post-Cured 4h at 200°C) · RANGE · 150 °CUnit: % | 10–25 % | — % |
| Compression Set (22h at 100°C) · Peroxide-Cured High-Temperature Compound · RANGE · 100 °CUnit: % | — % | 15–30 % |
Machinability: Waterjet cutting and precision rotary die cutting; cryogenic machining used for custom surgical prototypes.
Formability / Cold Working: High-consistency rubber (HCR) is milled and molded via compression, transfer, and extrusion; liquid silicone rubber (LSR) is processed via two-component high-speed meter-mix liquid injection molding.
Heat Treatment & Annealing: Vulcanized via organic peroxide catalysts (for HCR) or platinum-catalyzed hydrosilylation addition cure (for LSR). Post-curing at 200°C for 2 to 4 hours is mandatory to volatilize cyclic siloxanes and optimize compression set.
Machinability: Cryogenically machined; waterjet cut without abrasive garnets for pure elastomer gaskets.
Formability / Cold Working: Readily compounded in internal mixers with high paraffinic oil and carbon black loading. Extruded into dense and sponge weatherstrip profiles with continuous microwave/hot-air vulcanization (HAV) lines; precision injection molded.
Heat Treatment & Annealing: Vulcanized via sulfur-accelerator systems for rapid extrusion cure or organic peroxide systems (dicumyl peroxide, DTBP) for superior compression set, heat resistance up to 150°C, and steam resistance.