1.1   This specification2 covers polytetrafluoroethylene (PTFE) prepared by coagulation of a dispersion. These PTFE resins are homopolymers of tetrafluoroethylene or modified homopolymers containing not more than 1 % by weight of other fluoromonomers. The materials covered herein do not include mixtures of PTFE with additives such as colors, fillers, or plasticizers; nor do they include reprocessed or reground resin or any fabricated articles because the properties of such materials have been irreversibly changed when they were fibrillated or sintered.