Chemical resistant hose is to transport chemical, solvent and corrosive liquid. PTFE, FEP and PFA are all common fluorinated polymer materials. They are different in chemical resistance.
1. Chemical property
PTFE: It is the most common fluorinated polymer. It has excellent chemical resistance and inert chemical property. Besides, it almost not reacts with any substances. In addition, it can work in a high temp.
FEP: Compared with PTFE, FEP has lower chemical inertness. But it still has good chemical resistance and is a material which can bear high temp.
PFA: It is similar to FEP in chemical property. But PFA can work at higher temp. Besides, it can resist heat.
2. Melt processability
PTFE: Due to the very high melting temp of PTFE, its melt processability is poor. And it usually adopts pressing and sintering method to process.
FEP: FEP has a lower melting temp and is easier to process into various shapes than PTFE. Such as extrusion and injection molding.
PFA: PFA also has a low melting temp. Thus it is easier to produce parts through extrusion and injection molding.
PTFE: PTFE is opaque and generally white.
FEP and PFA: Both FEP and PFA are clear. Thus you can check the internal structure and the state of the medium.
PTFE: widely used for seal, pipe, valve, bearing and other fields. It’s also ideal for non-stick surface coating.
FEP: ideal for coating, pipe, cable insulation, etc
PFA: Due to its high temp and chemical resistance, PFA is widely used in semiconductor, chemical industry, medical device, aerospace and other fields.
From above we can see that these 3 materials have their own features. But at the same time, they are similar to each other in some aspects. While when you choose the material, you should based on the demand of your special work. Besides, focus on the working condition.