Rating
| Concentration | 20 °C | 50 °C | Remark |
|---|---|---|---|
| 1 % | A | A | |
| 30 % | A | A | |
| 45 % | – | – | |
| 50 % | A | A | |
| 60 % | – | – | |
| concentrated | – | – |
Material comparison at 20 °C
Resistance overview
FEP shows excellent resistance to Sodium Hydroxide (Caustic Soda) across all 3 tested concentrations (1 %, 30 %, 50 %) 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
Sodium Hydroxide (Caustic Soda) is commonly encountered in cleaning and sanitation and chemical processing. FEP (Fluorinated ethylene propylene) is a fluoropolymer typically used for seals, gaskets, valve seats and lined equipment. Because Sodium Hydroxide (Caustic Soda) is classified as corrosive, the choice of containment material is especially critical to prevent leaks, equipment damage, and safety hazards.
Practical recommendation
No resistance data is available for FEP in contact with Sodium Hydroxide (Caustic Soda). Before using this combination, consult the material manufacturer or conduct independent testing.
Did you know?
In industrial practice, FEP components exposed to Sodium Hydroxide (Caustic Soda) are typically inspected for swelling, discoloration, or loss of mechanical strength as early indicators of chemical attack.
Materials rated A or B at 20 °C
Based on the row for 60 %, 20 °C.
- Thermoplastics
- HDPE A, PP A, LDPE A, Nylon (PA) A, Polystyrene A, Polysulfone A, PMP A
- Fluoropolymers
- PTFE A
- Elastomers
- EPDM A, NBR B
- Metals
- SS 316 A, SS 304 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.