Halar® ECTFE for Coatings
Halar® ECTFE, a copolymer of ethylene and chlorotrifluoroethylene, is a semi-crystalline melt processable partially fluorinated polymer. It is available in different grades that are specifically designed for electrostatic powder coating.
Halar® ECTFE is particularly suitable for use as a coating material in protection and anti-corrosion applications thanks to its unique combination of properties.
Performance
Halar® ECTFE, a copolymer of ethylene and chlorotrifluoroethylene, is a semi-crystalline melt processable partially fluorinated polymer.
Halar® ECTFE is particularly suitable for use as a coating material in protection and anti-corrosion applications thanks to its unique combination of properties.
Key features
- Very good chemical and thermal resistance
- Optimum permeation resistance
- Outstanding flame resistance
- Very good surface characteristics
- Surface smoothness
- Purity
Processing
Halar® ECTFE is available in different grades that are specifically designed for electrostatic powder coating, fluidized bed coating, or both.
Electrostatic Powder Coating
Generally the procedure involves substrate preparation, spray coating, baking and cooling. Several passes maybe required to obtain the desired Halar® ECTFE load and build up coating thickness.
Fluidized Bed Coating
Generally preheated items can be coated by dipping directly into the fluidized powder followed by baking. The dipping and baking operation can be repeated to achieve multiple coats and build up the desired coating thickness.
Markets and Applications
Typical applications served by Halar® ECTFE include those in contact with highly corrosive or ultrapure chemicals such as strong inorganic bases and strong mineral and oxidizing acids including:
- Vessels
- Reactors
- Semiconductor chemical storage tanks and ductwork
- Piping systems
- Centrifuges
- Agitators
- Exhaust hoods
- Filters
- Electroplating equipment
Pharma & Chemical Industry
Exhaust Duct Coatings: Halar® ECTFE coated stainless steel exhaust duct systems are designed to handle a wide range of corrosive exhaust streams found in a variety of industrial applications, including clean rooms.
- Chemical resistance
- Barrier properties
- Outperform plastic and FRP duct with improved safety and corrosion resistance
- Reduction or elimination of the buildup of salt deposits and debris that can reduce airflow approved by Factory Mutual for use in fume and smoke exhaust systems, without sprinklers.
High Purity Applications
Static soak testing conducted on Halar® ECTFE in ultrapure water and high purity chemicals shows extremely low levels of metallic and organic extractables. Additional dynamic rinse data validates Halar® ECTFE as suitable for high purity systems in the semiconductor, biotech and pharmaceutical industries. Halar® ECTFE exhibits very low fluoride ion leach out.
Semiconductors
Halar® ECTFE coatings meet stringent standards for chemical and temperature resistance demanded for fab equipment and clean rooms. For example it is widely used as coatings of exhaust duct systems.
Fab Equipment: Halar® ECTFE coatings ensure that productivity and purity standards are met in semiconductor processing environments. Process exhaust ducting produced from Solvay fluoropolymers meet critical industry standards including those of FM Global. Halar® ECTFE deliver exceptional corrosion resistance and thermal stability.
Process Exhaust Ducting: Halar® ECTFE delivers exceptional results in semiconductor environments. It is used as a coating in exhaust ducts, vessels and process equipment: powder coatings have been used successfully for fire safety and corrosion protection of exhaust duct systems that must meet the FM4922 fire safety standard. Halar® ECTFE coated ductwork offers exceptional surface smoothness reducing the risk of contamination buildup and corrosion.
Fluid Handling Systems: Delivery, storage, filtration and processing are some of the steps integral to a fluid handling system. Fluoropolymers, thanks to their superior capabilities to withstand extreme chemicals and temperatures, are widely in use in semiconductor operations.
Halar® ECTFE coatings are the best choice for key components such as: valves, pipe, tanks, vessels, and heat exchangers.
Waste Disposal: The substances considered waste products of semiconductor manufacturing are likely to be corrosive, ignitable, reactive and/or toxic. Fluoropolymers offer superior strength and resistance to acids used in the etch, stripping and cleaning processes, as well as abrasion resistance to slurries and effluents. Piping and fittings, valves and other components coated with Halar® ECTFE offer reliable performance for waste disposal systems.
Case Studies
Halar® ECTFE stack liner
Halar® ECTFE-lined chimney remains maintenance-free
After 15 years, a fiberglass-reinforced FRP/Halar® chimey liner is still in good working order without any repairs. The chimney is part of a power station in the North Jutland region of Denmark. The liner is exposed to sulfuric acid at 110°C. Recent inspections showed no signs of chemical attack by the exhaust gas and no surface cracking was observed.
Chlorine scrubber
Fluoropolymer lining for a chlorine scrubber
An FRP/Halar® ECTFE dual laminate chlorine scrubber installed in a petrochemical plant delivered continuous service for 14 years. After the plant was shut down, the liner was inspected and found to be in excellent condition despite its exposure to chlorinated hydrocarbons combined with hydrochloric acid and molecular chlorine.
Fluoropolymer-lined process vessel
Long-term performance of a fluoropolymer-lined process vessel
A Halar® ECTFE-lined holding tank was undamaged after 23 years of service. It handled alkaline-based fluids and active chlorine in a vinyl chloride monomer plant.
Typical Properties
| Property | Test Method | Units | Halar® ECTFE |
| Melting point | °C | 240-245 | |
| Specific gravity | 1.68 | ||
| Max continuous service temperature | °C | 150 | |
| Oven process temperature | °C | 250-280 | |
| Thermal expansion coefficient | 10-5/°C | 8 | |
| Flexural modulus @ 22°C | ASTM D790 | MPa | 1,700 |
| Tensile modulus @ 22°C | ASTM D638 | MPa | 1,700 |
| Yield stress @ 22°C | ASTM D638 | MPa | 32 |
| Tensile strength at break @ 22°C | ASTM D638 | MPa | 48 |
| Hardness Rockwell R | ASTM D785 | 90 | |
| Hardness Pencil | HB-2B | ||
| Hardness Shore D | ASTM D2240 | 70-75 | |
| Impact strength notch Izod @ 25°C | J/m | no break | |
| Flammability | 94 V-O | ||
| Oxygen index | % | 60 | |
| Volume resistivity | ASTM D257 | ohm.cm | 1016 |
| Dielectric constant @ 1 MHz | 2.5 | ||
| Dielectric strength 3mm thick | kV/mm | 14.5 | |
| Dissipation factor @ 1 MHz | 0.009 | ||
| Water absorption | ASTM D570 | % | <0.1 |
| Permeability (cm3(STP)* mm/m2*atm*24h) *102 | |||
| O2@ 25°C | 0.2 | ||
| N2@ 25°C | 0.1 | ||
| H2O (vapor) @ 25°C | 7.5 | ||
| Permeability (g*mm/m2*24h) | |||
| HCl 37% @ 50°C | 0.5 | ||
| Methanol @ 50°C | 0.3 | ||
| H2O (liq.) @ 50°C | 0.5 | ||
| Low temperature embrittlement | °C | <-76 |