PTFE fiber is a chemically resistant material.
It is used in woven form in certain pump packings[1] as well as in nonwoven form in hot gas bag filters for industries with corrosive exhausts.
[2][3] Because PTFE is relatively insoluble and has a very high melting point, PTFE fibers can not be fashioned from conventional melt or solution spinning.
The remnant char gives the fiber a brown color.
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