Rotational molding fluoropolymers

With the exception of two fluoropolymers, PVF and PTFE, the rest of the resins described in this entry can be processed by standard melt-processing techniques, such as injection, transfer and blow molding, extrusion, and rotational molding. Process equipment for fluoropolymers must be made from corrosion resistant alloys because of the corrosive compound that may be produced when fluoropolymers are heated above their melting points. Higher melt viscosity of these resins may require more powder and higher pressure rating equipment. 

Aside from PTFE and PCTFE, copolymers of TFE and a few other fluorocarbon polyuners are processed by melt-processing methods. Commercial fluoropolymers that have found application in chemical processing industries include PFA, FEP, ETFE, ECTFE, and PVDF. These plastics are fabricated into parts by common techniques such as injection molding, transfer molding, blow molding, compression molding, rotational molding, and extrusion (Table... 

Table 10.15. Rotational Molding Troubleshooting Guideline for Fluoropolymers...

There are two distinct families of fluoropolymers perfluorinated (like PTFE) and the partially fluori-nated (like PVDF) polymers. The major types that are rotationally molded are polyvinylidene fluoride (PVDF), ethylene-tetrafluoroethylene (ETFE), ethyl-ene-chlorotrifluoroethylene (EC IFF), andperfluoro-alkoxy (PFA). 

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