Perfluoroalkoxy alkane
PFA | |
---|---|
Density[1] | 2150 kg/m3 |
Flexural modulus(E) | 586 MPa |
Tensile strength(t) | 24 MPa |
Elongation @ break | 300% |
Folding endurance | No break |
Notch test | |
Melting point | 315 °C |
Maximum operating | |
temperature | 260 °C |
Water absorption (ASTM) | <0.03 % after 24 hours |
Dielectric constant (Dk) | |
at 1MHz | 2.1 |
Dissipation factor | |
at 1MHz | 0.0001 |
Arc resistance | < 180 seconds |
Resistivity at 50% R.H. | > 1016 Ω m |
Perfluoroalkoxy alkanes or PFA are fluoropolymers. They are copolymers of tetrafluoroethylene (C2F4) and perfluoroethers (C2F3ORf, where Rf is a perfluorinated group such as trifluoromethyl (CF3)). In terms of their properties, these polymers are similar to polytetrafluoroethylene (PTFE). The big difference is that the alkoxy substituents allow the polymer to be melt-processed. On a molecular level, PFA has a smaller chain length, and higher chain entanglement than other fluoropolymers. It also contains an oxygen atom at the branches. This results in a material that is more translucent and has improved flow, creep resistance, and thermal stability close to or exceeding PTFE.[2] Similarly advantaged processing properties are found in fluorinated ethylene propylene (FEP), the copolymer of tetrafluoroethylene and hexafluoropropylene.[3]
References
- ↑ "PTFE, FEP, and PFA Specifications". Boedeker Corp. 2007. Retrieved 2007-12-22.
- ↑ "PFA Properties". Fluorotherm Polymers. 2010. Retrieved 2014-02-12.
- ↑ Günter Siegemund, Werner Schwertfeger, Andrew Feiring, Bruce Smart, Fred Behr, Herward Vogel, Blaine McKusick "Fluorine Compounds, Organic" Ullmann's Encyclopedia of Industrial Chemistry, Wiley-VCH, Weinheim, 2002. doi:10.1002/14356007.a11_349