Rating
| Concentration | 20 °C | 50 °C | Remark |
|---|---|---|---|
| 12,5 % Cl | A | A | |
| 15 % | C | D | |
| dilute | A | A | |
| saturated | C* | – |
* estimated rating, given in the source without a temperature
Material comparison at 20 °C
Resistance overview
The resistance of PVDF to Sodium Hypochlorite (Bleach) is concentration-dependent. Across the 4 tested concentrations (12,5 % Cl, 15 %, dilute, saturated), the 20 °C rating ranges from A at lower concentrations to D at higher ones. This means engineers must verify which concentration their process actually involves before relying on a single rating. However, at 50 °C the resistance rating drops, indicating that temperature must be factored into the design. For heated applications, additional testing under actual service conditions is strongly recommended.
Application context
Sodium Hypochlorite (Bleach) is commonly encountered in bleaching and pulp and paper. PVDF (Polyvinylidene fluoride) is a fluoropolymer typically used for seals, gaskets, valve seats and lined equipment. Because Sodium Hypochlorite (Bleach) is classified as corrosive, the choice of containment material is especially critical to prevent leaks, equipment damage, and safety hazards.
Practical recommendation
PVDF has limited resistance to Sodium Hypochlorite (Bleach) 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, PMP, Polystyrene, Polysulfone offer significantly better resistance and are rated A.
Did you know?
Polyvinylidene fluoride is commonly chosen for seals, gaskets, valve seats and lined equipment because of its combination of chemical resistance, mechanical strength, and cost-effectiveness.
Materials rated A or B at 20 °C
Based on the row for 15 %, 20 °C.
- Thermoplastics
- HDPE B, PP B, PVC Rigid A, LDPE B, Polycarbonate B, Polystyrene A, Polysulfone A, PMP A, SAN A
- Fluoropolymers
- PTFE A, FEP A, ECTFE/ETFE A
- Elastomers
- Viton (FPM) A
- Metals
- SS 316 B
About PVDF
PVDF resists acids, halogens and hydrocarbons. Strong bases, amines, ketones and esters attack it. Service temperature is up to about 150 °C.
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.