PFA Compression Molding

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).

The type and number of side chains provided by the comonomers determine the thermomechanical properties of the PFA polymer.  Generally, a high number of side chains will lower the thermal rating, melting point and creep resistance but will increase the tenacity (stress/strain at break) and the flex-life.

The bigger the side chains, the less comonomer is needed to modify the polymer backbone to the same degree, which allows the design of resins with higher thermal ratings.

Higher molecular weight leads to higher viscosity and a correspondingly lower melt flow index (MFI).  Lower MFI resins exhibit higher tenacity and higher flex-life.  Comonomers with bigger side chains can be used to offset the negative effect of low molecular weight (high MFI) on resins that would otherwise have lower tenacity and flex life.

PFA Properties

PFA combines the processing ease of conventional thermoplastic resins with the superior properties of PTFE.  The melt viscosity of PFA is over a million times lower than that of PTFE.

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.

1. •Excellent universal resistance to chemicals and solvents
   

2. •Superior creep resistance at upper service temperature
   

3. •Excellent stress crack resistance
   

4. •Low coefficient of friction
   

5. •More than 10 times the flex-life of FEP
   

6. •Excellent flexibility
   

7. •Smoother surface that PTFE or FEP
   

8. •Low gas permeability
   

9. •Available in high-purity grades with extremely low levels of extractable trace elements, fluoride ions and other anions
   

10. •Available in grades with increased permeation resistance
    

11. •Available in anti-static industrial grades
    

12. •Exceptional flame resistance, rated UL 94 V-0
    

13. •Resists ignition, has a limiting oxygen index (LOI) of greater than 95
    

14. •Some grades may be used in food contact applications in compliance with FDA 21 CFR 177.1550
    

15. •Excellent low-temperature toughness
    

16. •Extremely high weathering resistance and UV stability
    

17. •Exceptionally low dielectric constant and dissipation factor, like those of PTFE, but with dielectric strength more than four times higher than
    

18. •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:

1. •Semiconductor processing equipment (due to superb chemical resistance and high purity/low extractables), where purity in the parts-per-
   

2. •billion range is needed
   

3. •Chemical processing industry (CPI) components
   

4. •Bulk chemical distribution
   

5. •Fluid-handling components
   

6. •Laboratory components
   

Compression-molded PFA Parts

1. •Fluid-handling components
   

2. •Valves
   

3. •Linings for tanks and vessels
   

4. •Fluid containers
   

5. •Pipes
   

6. •Wafer carriers
   

7. •Benches
   

8. •Sinks for wet benches
   

9. •Cabinets
   

10. •Filters
    

11. •Fittings
    

12. •Labware
    

PFA Compression Molding Resins

Teflon® PFA from DuPont™

1. •Teflon® PFA 340
   

2. •Teflon® PFA 345
   

3. •Teflon® PFA 350
   

4. •Teflon® PFA 9724
   

5. •Teflon® PFA 9725
   

6. •Teflon® PFA 416HP
   

7. •Teflon® PFA 440HP
   

8. •Teflon® PFA 440HPA
   

9. •Teflon® PFA 440HPB
   

10. •Teflon® PFA 445HP
    

11. •Teflon® PFA 450HP
    

12. •Teflon® PFA 451HP
    

13. •Teflon® PFA 940HP Plus
    

14. •Teflon® PFA 945HP Plus
    

15. •Teflon® PFA 950HP Plus
    

16. •Teflon® PFA 951HP Plus
    

Hyflon® PFA from Solvay Specialty Polymers

1. •Hyflon® PFA 420
   

2. •Hyflon® PFA M620
   

3. •Hyflon® PFA M640
   

NEOFLON™ PFA from Daikin America

1. •NEOFLON™ AP-230 PFA
   

2. •NEOFLON™ AP-231SH PFA