Rating
| Concentration | 20 °C | 50 °C | Remark |
|---|---|---|---|
| aqueous | A | A | |
| technical grade | A | A |
Material comparison at 20 °C
Resistance overview
FEP shows excellent resistance to Hydrocyanic Acid (Hydrogen Cyanide) across all 2 tested concentrations (aqueous, technical grade) at 20 °C, making it a reliable choice for storage, transfer, and handling applications involving this chemical at any of the tested strengths. The rating remains stable between 20 °C and 50 °C, which means this material can also handle moderately elevated process temperatures without additional risk.
Application context
Hydrocyanic Acid (Hydrogen Cyanide) is commonly encountered in metal finishing and laboratory work. FEP (Fluorinated ethylene propylene) is a fluoropolymer typically used for seals, gaskets, valve seats and lined equipment. Since Hydrocyanic Acid (Hydrogen Cyanide) is flammable, material selection must also consider the risk of static charge buildup and the need for proper grounding in storage and transfer systems.
Practical recommendation
FEP can be used with confidence for Hydrocyanic Acid (Hydrogen Cyanide) containment and handling. The A rating indicates that the material shows no significant change in weight, dimensions, or mechanical properties after prolonged contact under test conditions. This holds true at both 20 °C and 50 °C, giving a good safety margin for typical process environments.
Did you know?
The ratings shown here apply to pure Hydrocyanic Acid (Hydrogen Cyanide) in contact with the base fluoropolymer. In real-world applications, additives, pigments, and fillers in the material can shift resistance in either direction.
Materials rated A or B at 20 °C
Based on the row for aqueous, 20 °C.
- Thermoplastics
- HDPE A, PP A, PVC Rigid A, LDPE A, PVC Flexible A, Polystyrene A
- Fluoropolymers
- PTFE A, PVDF A
- Elastomers
- EPDM A, Viton (FPM) A
- Metals
- SS 316 A, SS 304 A, Aluminium A
About FEP
FEP has nearly the chemical resistance of PTFE and can be melt-processed. Its service temperature, about 200 °C, is lower than that of PTFE.
Rating scale
- A very good resistance
- B good resistance
- C limited resistance
- D not resistant
- – no data
- K no general statement possible
A rating marked * is an estimate in the source, not a test result. An estimate is given as one value without a temperature.
About this data
The ratings come from the chemical resistance list published by Bürkle GmbH, which compiled them from raw-material manufacturers’ data. They describe laboratory tests on the raw material at 20 °C and 50 °C.
A finished part also sees pressure, mechanical stress, welds and mixtures that a laboratory test does not. Treat the rating as a first filter and test under your own conditions before relying on it.