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PTFE sheet is quite a soft engineering plastic and may be difficult to hold without damaging or crushing. Also because of its inherent low friction and resulting “slipperiness”, PTFE sheet can also make it difficult to work with and hold in place again while being machined. Another consideration is its tendency to produce strings of long swarf, which may wrap around any cutters or tooling.

Here again, the touted low friction and “slipperiness” of PTFE becomes a challenge. PTFE sheet must undergo surface preparation prior to bonding, normally by etching, using a solution of sodium and naphthalene in tetrahydrofuran. Adhesive manufacturers have developed proprietary primers which make it possible for the surface to be primed ready to accept an adhesive. Once the surface of the material is prepared, a number of adhesives can then be used including, epoxies, polyurethanes and acrylics. Companies such as Loctite® and 3M® have now developed a special acrylic based adhesive that can bond directly to PTFE without the need for preparation other than a preliminary wipe with a cleaning solvent.

PTFE is pretty much safe against most known elements and compounds. It is attacked only by the alkaline metals in the elementary state, by chlorine trifluoride, and by elementary fluorine at high temperatures and pressures. PTFE doesn’t dissolve in most solvents at temperatures up and around 300°C. Fluorinated hydrocarbons can cause an amount of expansion which is not permanent. Some oils which are highly fluorinated and at temperatures over 300°C can inflict a dissolving affect upon this excellent engineering plastic.