PFA (polyfluoroalkoxy)
PFA (polyfluoroalkoxy) is a fully fluorinated, semi-crystalline copolymer of TFE and a minor amount of a PAVE (perfluoroalkyl vinyl ether), such as PMVE (perfluoromethylvinyl ether), PEVE (perfluoroethylvinyl ether), or PPVE (perfluoropropylvinyl ether).
PFA Properties
PFA offers the highest temperature rating and broadest chemical resistance of any melt-processible fluoropolymer, making it ideal for extreme chemical and thermal environments. PFA is similar to FEP in many ways but in general has better mechanical properties at higher temperatures.
PFA is one of the few plastics that is suitable for use in high-temperature and low-temperature applications. Products made from PFA can operate at continuous service temperatures from -260 °C (-436 °F) to 260°C (500°F), similar to the range for PTFE.
Excellent universal resistance to chemicals and solvents
Superior creep resistance at upper service temperature
Excellent stress crack resistance
Low coefficient of friction
More than 10 times the flex-life of FEP
Excellent flexibility
Smoother surface that PTFE or FEP
Low gas permeability
Available in high-purity grades with extremely low levels of extractable trace elements, fluoride ions and other anions
Available in grades with increased permeation resistance
Available in anti-static industrial grades
Exceptional flame resistance, rated UL 94 V-0
Resists ignition, has a limiting oxygen index (LOI) of greater than 95
Some grades may be used in food contact applications in compliance with FDA 21 CFR 177.1550
Excellent low-temperature toughness
Extremely high weathering resistance and UV stability
Exceptionally low dielectric constant and dissipation factor, like those of PTFE, but with dielectric strength more than four times higher than that of PTFE
PFA Applications
PFA is used for many applications that are similar to those in which PTFE and FEP are used, but PFA is particularly preferred for applications that require extended service in hostile environments with high chemical, thermal and mechanical stresses:
Semiconductor processing equipment (due to superb chemical resistance and high purity/low extractables), where purity in the parts-per-billion range is needed
Chemical processing industry (CPI) components
Bulk chemical distribution
Fluid-handling components
Laboratory components