Rating
| Concentration | 20 °C | 50 °C | Remark |
|---|---|---|---|
| aqueous | A | – | |
| concentration not stated | C | C |
Material comparison at 20 °C
Resistance overview
The resistance of NBR to Calcium Sulfide is concentration-dependent. Across the 2 tested concentrations (aqueous), the 20 °C rating ranges from A at lower concentrations to C at higher ones. This means engineers must verify which concentration their process actually involves before relying on a single rating. 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
Calcium Sulfide is commonly encountered in metal finishing and laboratory work. NBR (Nitrile butadiene rubber) is an elastomer typically used for seals, O-rings, hoses and flexible connections. Because Calcium Sulfide is classified as corrosive, the choice of containment material is especially critical to prevent leaks, equipment damage, and safety hazards.
Practical recommendation
NBR has limited resistance to Calcium Sulfide and should only be used for short-term or intermittent contact at ambient temperature. The C rating means the material undergoes noticeable changes — swelling, loss of strength, or surface degradation — that make it unsuitable for permanent installations. For prolonged or continuous exposure, Acetal (POM), PP, PVC Rigid offer significantly better resistance and are rated A.
Did you know?
Chemical resistance testing according to DIN and ISO standards typically evaluates weight change, dimensional change, and retention of tensile strength after immersion.
Materials rated A or B at 20 °C
Based on the row for concentration not stated, 20 °C.
- Thermoplastics
- PP A, PVC Rigid A, Nylon (PA) B, Acetal (POM) A, Polycarbonate B
- Fluoropolymers
- PTFE A, PVDF A, FEP A
- Elastomers
- EPDM A, Viton (FPM) A
- Metals
- SS 316 A, SS 304 A, Aluminium A
About NBR
Nitrile rubber resists mineral oils and fuels. Ketones, esters, chlorinated solvents, strong oxidisers and ozone attack it.
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.