PURIFICATION PROCESS

摘要

Polytetrafluoroethylene coagulate obtained from aqueous dispersion polymerization of tetrafluoroethylene in the presence of volatile initiator, surfactant, and possibly wax, is purified of these contaminants by exposing the coagulate to heated air with the coagulate being formed as a shallow bed on a fabric of polymer filament, the heated air passing through the bed from top to bottom to volatilize the contaminants including the water content of the coagulate and thereby cause them to leave the bed through openings in the fabric.