"Silicone or rubber?" is the wrong question — silicone is a rubber, one member of a large elastomer family. The right question is which elastomer best fits your temperature, fluid, food-safety and cost requirements. This guide compares silicone against the most common alternatives.
Elastomer Comparison at a Glance
| Elastomer | Temperature range | Oil & fuel | Food contact | Relative cost |
|---|---|---|---|---|
| Silicone (VMQ) | -60°C to +230°C | Poor (swells in oil) | Excellent | Medium-high |
| Fluorosilicone (FVMQ) | -60°C to +200°C | Good | Good | High |
| FKM (Viton-type) | -20°C to +250°C | Excellent | Limited | High |
| EPDM | -50°C to +150°C | Poor (swells in oil) | Good | Low |
| NBR | -30°C to +120°C | Excellent | Limited | Low |
| HNBR | -30°C to +150°C | Excellent | Limited | Medium |
Temperature ranges are general guidance for continuous service and vary by compound. Always confirm the specific grade against your application.
When to Choose Silicone
Silicone is the best choice when you need a combination of wide temperature tolerance, food or skin safety, and flexibility. CYES SILICONE molds silicone in Shore A 20–80 across food-grade (FDA / LFGB), medical-grade and industrial grades.
- Food and baby products — FDA 21 CFR and LFGB compliant grades are inert and safe for repeated contact.
- Wide temperature range — silicone stays flexible from -60°C to +230°C, far beyond most organic rubbers.
- Transparency and color — silicone can be transparent or Pantone-matched for brand consistency.
When an Alternative Elastomer Wins
- Prolonged oil or fuel exposure → FKM, NBR or HNBR resist swelling that would degrade silicone. FVMQ is the silicone-family compromise when you need oil resistance plus low-temperature flexibility.
- Lowest cost, no oil contact → EPDM for outdoor, ozone and hot-water sealing.
- High-pressure oil sealing → NBR or HNBR for hydraulic and automotive fluid systems.
If your part faces oil, fuel or solvent, standard silicone is usually the wrong material. Tell us your fluid environment and we will recommend silicone, FVMQ or a non-silicone compound accordingly.
Making the Final Call
The decision comes down to four inputs: temperature, fluid exposure, food-safety certification and budget. Our engineers evaluate all four during DFM review and recommend a compound — silicone or otherwise — with the test data to back it up.
Beyond the six elastomers above, we also source and mold additional rubber compounds — including CR (chloroprene), CSM (Hypalon-type), IIR (butyl) and NR (natural rubber) — on request for specialized sealing, vibration or fluid-service requirements. Tell us your environment and we will match the right elastomer.
For the deeper silicone-specific view, see our silicone material selection guide and our specialty molding materials page covering FVMQ, PEEK, PA66-GF and functional silicone grades.