Etching of Teflon® Wire, Cable and Tubing

Etching of Teflon® Wire, Cable, and Tubing.

RDS Wire & Cable, Inc. has in-house capabilities for surface treatment of fluoropolymer-insulated wires, cables, and tubing, to make these materials bondable to themselves and to other materials.

Teflon® insulations such as PTFE, FEP, and PFA are well known for their chemical and heat resistance, low coefficients of friction, and outstanding dielectric properties. Many of the applications for these materials require adhesion to the fluoropolymer, and this can be accomplished by etching:

Fluoropolymer jacketed high temperature wire or cable must be etched to allow “potting” or sealing of a connector.

The Outside Diameter of small diameter, thin wall fluoropolymer tubing must be etched in order to bond to an over-wrap or over-extrusion, or for sealing when the tubing is used as an additional insulation over a termination point.

To enable the use of fluoropolymers in these applications, their surface must be altered enough to promote bondability without changing their other very desirable characteristics. The ‘active metals’ are the only chemicals known to react with the fluoropolymers. Sodium is the most commonly used material. It is a safe and environmentally sound process. The etching process is actually a chemical reaction between the sodium in the etchant formula and the fluorine in the polymer. The sodium in the solution strips the fluorine from the carbon backbone and promotes its replacement with the organic species responsible for adhesion. This reaction takes place to a depth of only a few angstroms leaving the polymer unaffected but rendering the surface completely bondable with conventional adhesives.

The process will change the color of the wire or tubing (adding a light to dark brown tint for PTFE and PFA – FEP will show a very slight color change).  The treated product is sensitive to humidity and UV light exposure, so care should be taken to keep the material wrapped or in an enclosure if it is to be stored, rather than used immediately.

For information on the average increased bondability of RDS Wire & Cable's etching system, please see here

RDS Wire & Cable, Inc. has short lead-times for etching and minimum quantities can be as low as 100 feet per item. Please contact us to discuss your Teflon® etching needs.