PVDF – polyvinylidene fluoride
Stiff, weldable fluoropolymer for the chemical industry up to 140 °C
PVDF is the fluoropolymer of the chemical industry: it has almost all of PTFE's resistance to acids, halogens and oxidizers, but it is much stiffer, more abrasion resistant and weldable. It works up to about 140 °C, resists UV and weathering, and is used in tanks, piping, pumps and valves.
Designations and equivalents
| System | Designation |
|---|---|
| Abbreviation (ISO 1043) | PVDF |
| Trade names | TECAFLON PVDF (Ensinger); Symalit PVDF 1000 (MCAM); Kynar / Solef (resins) |
Standards by product form
| Form | Standard |
|---|---|
| Resin and stock shapes | ASTM D3222* |
| Food contact | FDA 21 CFR 177.2510 (depending on grade) |
| Machined part to drawing | ISO 2768 tolerance or as per drawing |
Composition and filler
Pure polymer
| Component | Content |
|---|---|
| PVDF (polyvinylidene fluoride) | 100% |
Mechanical properties
Typical values from the stock-shape manufacturer's catalog, 23 °C; ISO/ASTM methods as per the source
| Property | Value |
|---|---|
| Tensile strength | 62 MPa |
| Modulus of elasticity (tensile) | 2,200 MPa |
| Elongation at break | 17% |
| Compressive strength | 59 MPa |
| Hardness | Shore D 80 |
| Notched impact | 132.9 J/m |
Typical physical and thermal properties
| Property | Value |
|---|---|
| Density | 1.78 g/cm³ |
| Maximum continuous service temperature | 140 °C |
| Maximum short-term temperature | 150 °C |
| HDT (1.8 MPa) | 113 °C |
| Melting point or glass transition | 171 °C |
| Linear thermal expansion | 180 µm/m·K |
| Thermal conductivity | 0.25 W/m·K |
| Water absorption (24 h) | 0.02% |
| Dielectric strength | 20.1 kV/mm |
| Flammability (UL 94) | V-0 |
Calculate the weight of PVDF – polyvinylidene fluoride bar, plate or pipe →
Chemical resistance
| Medium | Resistance |
|---|---|
| Acids | Excellent (including halogens and oxidizers) |
| Bases (alkalis) | Good to limited: strong bases and amines attack it at temperature |
| Solvents | Good; polar ketones and esters (e.g. acetone, DMF) attack it |
| Hydrocarbons and oils | Excellent |
| Steam and hot water | Good (Ensinger: + for hot water/bases) |
Stock forms and sizes
- Rod (round bar)
- Sheet (plate)
- Tube and bushing
- Weldable sheet
- Raw material: rod (round bar), sheet (plate) and tube, cut to size
- Machined part to drawing or sample, in the same order as the metal parts
- Lot certificate of conformity; FDA/EU 10/2011 declaration when the grade allows
Service temperature, machining and assembly
| Item | Usual practice |
|---|---|
| Service temperature | Continuous service up to 140 °C, short peaks up to 150 °C (unloaded; under load, limited by HDT and creep). |
| Annealing (stress relief) | Stress-relief annealing after welding or heavy machining. |
| Bonding and welding | Welds well by hot plate, hot air and extrusion welding: it is the fluoropolymer used to build tanks and pipes. |
| Machining | Machines well with a sharp tool. |
Typical applications
- Chemical tanks, ducts and piping
- Pump casings, impellers and valves
- Electroplating and pickling parts
- Ultrapure water and semiconductor equipment
Alternatives: PTFE for temperatures above 150 °C or strong bases; PP for less aggressive chemicals at lower cost.
Frequently asked questions
Which standards cover PVDF?
Resin and stock shapes: ASTM D3222*. Food contact: FDA 21 CFR 177.2510 (depending on grade). Machined part to drawing: ISO 2768 tolerance or as per drawing.
Up to what temperature can PVDF be used?
Continuous service up to 140 °C, short peaks up to 150 °C (unloaded; under load, limited by HDT and creep).
Which materials can replace PVDF?
PTFE for temperatures above 150 °C or strong bases; PP for less aggressive chemicals at lower cost.
PVDF or PTFE?
PTFE resists more chemicals and higher temperature; PVDF is stiff, abrasion resistant and weldable, so it is preferred for tanks, pipes and pump casings.
