Mechanical and physical charactersations of polytetrafluoroethylene by high velocity compaction

Commercially available PTFE is a thermoplastic polymer of unusually high molecular weight. PTFE cannot be manufactured with the conventional techniques used for lower molecular weight polymers such as extrusion or injection molding, and its current processing is long and expensive. A new process, High Velocity Compaction (HVC), allows processing PTFE within short processing times. In HVC, repeated impacts at a temperature close to but below the polymer melting point leads to a good sintering of semi-crystalline polymer powders. Physical and mechanical properties of PTFE processed by HVC are investigated showing that density, crystal weight fraction and wear properties are improved compared to the conventional sintering technique.