synthetic resin belonging to the family of organic polymers, prepared by treatment of an aqueous suspension of chlorotrifluoroethylene with a catalyst composed of a mixture of sodium persulfate and sodium hydrogen sulfite. Polychlorotrifluoroethylene, sometimes abbreviated to CTFE resin, is similar to polytetrafluoroethylene; although it is slightly less resistant to chemical attack, it has the important advantage that it can be shaped by molding or extrusion into solid articles such as gaskets, linings for containers, and parts for valves and pumps. Dispersions of the resin in organic liquids can be used to form protective coatings on surfaces.