Methanol Resistant O-Rings
Compatibility ratings for 7 O-ring materials in Methanol service
Methanol is slightly harder on NBR than ethanol (B rather than A), but most elastomers cope — FKM, EPDM, VMQ, PTFE, FFKM and HNBR all rate A, making this one of the easier solvent services to specify.
Methanol (Alcohols) compatibility with the seven most common O-ring elastomers, rated on the standard A/B/C/D scale: A = excellent, B = good, C = fair, D = not recommended. This data also appears in our interactive chemical compatibility chart and is available machine-readable at /api/chemicals.json.
| Material | Rating | Guidance |
|---|---|---|
| NBR | B | good — suitable for most applications |
| FKM | A | excellent — recommended for continuous service |
| EPDM | A | excellent — recommended for continuous service |
| VMQ | A | excellent — recommended for continuous service |
| PTFE | A | excellent — recommended for continuous service |
| FFKM | A | excellent — recommended for continuous service |
| HNBR | A | excellent — recommended for continuous service |
Why These Ratings
- EPDM (A) — documented strengths include “Ketones and alcohols.”
- VMQ (A) — documented strengths include “Alcohols.”
- PTFE (A) — documented strengths include “Virtually all chemicals.”
- FFKM (A) — documented strengths include “Virtually all chemicals except molten alkali metals.”
AlcoholsService: Concentration & Temperature Notes
Smaller alcohols bite harder: methanol and ethanol rate NBR at B, while the larger isopropyl alcohol rates it A. Alcohols are polar solvents, so EPDM performs well across this category. Hot alcohol service increases plasticizer extraction — verify hardness change after exposure, not just volume swell.
Recommended
- FKM O-rings (A)
- EPDM O-rings (A)
- VMQ O-rings (A)
- PTFE O-rings (A)
- FFKM O-rings (A)
- HNBR O-rings (A)
Use With Caution
- NBR O-rings (B)
Avoid
No material is rated D for this chemical.
Related Chemicals (Alcohols)
Frequently Asked Questions
Is Methanol compatible with FKM (Viton) O-rings?
FKM is rated A for Methanol: excellent — recommended for continuous service. Ratings are general guidelines; concentration, temperature and exposure time all affect real-world compatibility, so validate critical applications with ASTM D471 immersion testing.
Is Methanol compatible with NBR (nitrile) O-rings?
NBR is rated B for Methanol: good — suitable for most applications. NBR is the lowest-cost elastomer, so when it earns an A or B rating it is usually the economical default; when it rates C or D, do not substitute it for a higher-rated material to save cost.
Can I use PTFE O-rings with Methanol?
PTFE is rated A for Methanol: excellent — recommended for continuous service. Remember that PTFE has no elastic memory — in demanding service it needs spring energization or an elastomer core (FEP/PFA encapsulation) to maintain sealing force.
What is the best O-ring material for Methanol?
FKM, EPDM, VMQ, PTFE, FFKM, HNBR are rated A (excellent) for Methanol in our compatibility data and are the recommended starting point for material selection. Final selection should also account for operating temperature, pressure and whether the seal is static or dynamic.
Can I use EPDM O-rings with Methanol?
EPDM is rated A for Methanol: excellent — recommended for continuous service. Always confirm the specific fluid concentration and temperature before specifying EPDM for this service.
Need O-Rings for Methanol Service?
Send us your fluid, concentration and temperature — our engineers will confirm the right compound. MOQ 1 piece.