I-PTFE yi-polytetrafluoroethylene,ekwabizwa ngokuba yiTeflon (Teflon), yimathiriyeli yokucoca ingxowa kwezona ndawo ziphakamileyoiintlobo ze.Ibhegi ye-PTFE yokumelana neemeko ezonakalisayo, inkonzoubomi beemfuno zemathiriyeli yokucoca yamathuba.