Polytetrafluoroethylene fiber

A fiber comprising polytetrafluoroethylene (PTFE), wherein said fiber has a tenacity greater than 0 36 g / d. The present invention provides a PTFE fiber having a tenacity greater than 0, 36 grams per denier (g / d). A range for the toughness is from 0 36 g / d to about 1 01 g / d, a preferred from about 0 50 g / d to about 0 80 g / d range. The fiber tenacity inventive PTFE is most preferably about 0 60 g / d. The inventive fiber has a peak engineering stress greater than 1, 6 g / d and a deformation of rupture greater than 15, 5 percent. A preferred peak engineering stress is greater than about 2, 0 g / d and a break strain is preferably greater than about 20 percent. More preferable is a peak engineering stress greater than about 2, 5 g / d and a break strain greater than about 25 percent. Still more preferably it is a peak engineering stress greater than about 3, 0 g / d and a break strain greater than about 30 percent. A preferred for the peak engineering stress range is from about 3 0 to about 5, 0 g / d, and a preferred break strain for the range is from about 20 to about 50 percent. Most preferably, the peak engineering stress is about 4, 4 g / d and the break strain is about 24 percent.