ECTFE - The Fluoropolymer Powerhouse
Ethylene-ChloroTrifluoroEthlylene, aka: ECTFE or Halar® is a copolymer of ethylene and chlorotrifluoro-ethlylene. I look at these niche fluoropolymers almost as boutique polymers engineered to boost specific properties and performance. But similar to carrying a mattress, when you pick up one end, the other end drops.
As we have discussed, PTFE is fully fluorinated homopolymer fortress that offers uniquely extreme properties in terms of temperature & chemical resistance but its limitations are melt processablity and mechanical properties.
In the case of ECFTE, we have a copolymer of ethylene monomer with its compliment of hydrogen atoms reacted with an ethylene monomer that contains 3 fluorine’s and one chlorine atom. ECTFE is a semi crystalline polymer with about 55% being a crystalline phase.
So what does all this mean in terms of why you would specify ECTFE in Semiconductor Wet Process applications?
| PVDF | PTFE (Virgin) | ECTFE | |
|---|---|---|---|
| Tensile Strength (ASTM D638, psi) | 6,300 | 3,600 | 7,900 |
| Tensile Modulus (ASTM D638, psi) | 290,000 | 80,000 | 240,000 |
| Flexural Modulus (ASTM D790, psi) | 290,000 | 72,000 | 240,000 |
| Chemical Resistance | Good | Inert | Very Good |
| Melting Temperature (F) | 336 | 621 | 468 |
| CLTE (ASTM D695,x10^-5, in/in/F) | 6.6 | 7.5 | 5.6 |
| Best in class | Excellent |
CHEMICAL RESISTANCE – ECFTE widens the chemical resistant footprint compared to PVDF, its closest fluoropolymer in terms of enhanced me- chanical properties. ECTFE generally offers excellent resistance within the pH range from 1-14 whereas PVDF has limitations mainly in the high alkaline range above a pH of 12.
ECTFE falls short of the almost inert properties of PTFE however ECTFE has extremely low permeation values in oxygen, chlorine gas and hydrochloric acid. Especially when compared to PTFE.
MECHANICAL PROPERTIES – ECFTE offers greatly enhanced mechanical properties over PTFE due to the chlorine atom and ethylene group with similar dimensional stability and mechanical properties of PVDF.
ECTFE is a melt processable super performance material with best in class fire safety, a superior surface, ultra purity with full range chemical resistance all while delivering a mechanically tough material.
CONTACT YOUR LOCAL PORT PLASTICS SALES OFFICE FOR ALL YOUR SEMICONDUCTOR NEEDS!
|
Download As PDF |
| ECTFE - PDF |