By Dick Chen – Aerospace Wire and Cable
Like many discoveries, PTFE or Teflon®, was discovered quite by accident. In 1938, Roy Plunkett, a Dupont engineer, made the discovery while attempting to make a new refrigerant. Due to the need for an extrudable or melt processable material that had many of the same great attributes, several other fluoropolymers like FEP, PFA, ETFE and HALAR, were developed and brought to market. All of these Fluoropolymers are copolymers of PTFE. They have proved to be excellent materials for wire and cable insulation. Following are some of the excellent properties that fluoropolymers provide for wire and cable design.
LONG SERVICE LIFE
These materials have outstanding retention of their properties after aging, even at high temperature and in the presence of solvents, oil, oxidizing agents, UV light and other environmental agents.
FLAME RESISTANCE
Fluoropolymers have high melting points. Their low rate of heat release and low smoke generation make them a great choice for Fire Alarm Cables.
DIELECTRIC
Fluoropolymers have high dielectric strength with a low dielectric constant. These low loss factors are great for Low Capacitance and Coaxial Cables. They are also great for the thin wall applications of Medical Cable and Robot Cable.
HIGH TEMPERATURE
Fluoropolymers retain their properties after exposure to high temperature. Their continuous service temperature is as high as 260°C. Many industries require High Temperature Cable for their manufacturing process.
HUMIDITY
Fluoropolymers are extremely hydrophobic and completely resistant to hydrolysis. They are good barriers to water permeation. Their typical properties and dimensional stability remain unchanged even after long immersion in water. Equipment operating at wet locations, such as Oil Drilling Cables often require fluoropolymers cables.
FRICTION
Fluoropolymers have the lowest coefficients of friction of any solid materials. They are great for cable jacketing material for cable installed in building plenum spaces (Plenum Cable).
CORROSION
Fluoropolymers resist even the most aggressive organic and inorganic chemical and solvents over a broad temperature range. Thus, they are excellent material for Chemical and Industrial Cables
LOW TEMPERATURE
Fluoropolymers retain their excellent properties even at cryogenic temperatures. Their temperature ratings are as low as -80° C. Thus, they work great as Freezer Cables.
AGING
Fluoropolymers are transparent to ultraviolet light and extremely resistant to oxidation, surface fouling, discoloration and embrittlement. This has been proven by tests conducted in Florida for periods up to 20 years in duration.
CONCLUSION
With all of these excellent properties, fluoropolymers are an excellent material for wire and cable design in applications such as industrial, building, medical, aerospace, robotics and many other industries.
