Fluoropolymer materials containing tetrafluoroethylene monomers, such
as PTFE, are significantly swollen by supercritical carbon dioxide at high temperatures
and pressures. The swollen fluoropolymer is processable by molding, extrusion,
and other techniques. In addition, the fluoropolymer may be sintered at significantly
lower temperatures compared to a nonswollen fluoropolymer material. The melting
temperature of fluorinated polymers containing tetrafluoroethylene and triflouroethylene
monomers which are swollen with supercritical carbon dioxide is significantly reduced,
thereby permitting manufacturing operations such as extruding and molding to be
performed at lower temperatures and with reduced risk of decomposition.