PTFE (TFE) and Kynar - PVDF are both experiencing long lead times.

Teflon  product PTFE (TFE) as well as Kynar-PVDF  manufacturing requires a mineral called Fluorspar which is mined in Mongolia and China. The worldwide need for this mineral has grown significantly, and also the supply has tightened. PTFE materials have high heat resistance, excellent chemical resistance and very low co-efficient of friction (slick) and is used throughout a good deal of applications from non-stick fry griddles to ptfe tape for home use. This particular mineral is a crucial raw materials within the manufacturing of fluoropolymers, fluorolubricants and a lot of refrigerants.This rise in demand linked with shortage of raw materials has caused a dramatic price increase (almost double over the past year), shortages, and we expect both these factors to keep at it in the near future.

Foraflon