Thermoplastic polymer with a high crystalline proportion, known for example by the brand name Teflon. Chemically extremely stable, is attacked only by dissolved or melted alkaline metals. Thermally stable up to min. 400 °C, excellent gliding characteristics, very low surface energy (approx. 18 mN/m), accordingly a strong hydrophobic and oleophobic effect; used as non-stick coating. Can be used in optical data transmission for its low hardness, non-transparency and very low refraction index. PTFE is considered practically “non-gluable” but by means of plasma activation with hydrogen as a process gas it can be activated in such a way that even very good bonding can be achieved with an ideally designed process. C-F bonds are broken up and the hydrogen reacts with the broken-off fluorine atom to form hydrogen fluoride, which is extracted via the vacuum pump. The carbon bond which is now free provided an excellent bonding spot for adhesives and coating materials.
Thermoplastic Polymer with high crystallinity. Very popular is the tradename Teflon or the abrevation PTFE. PTFE is most resistant against almost any chemical attack. The only material etching PTFE is a solution of alkali metals. This also is the only conventional method to provide surface properties for glueing, printing or painting. Therefore the method of plasma activation by a hydrogen plasma is a most important technology to treat PTFE surfaces. Plasma treatment can provide excellent adhesion for printing or glueing without use of any aggressive chemistry.
PTFE has unique properties in many respects: lowest surface energy of all solid materials, lowest coefficient of friction, excellent thermal stability.
The material therefore is frequently used for non adhesive coatings and devices for laboratory equipment.
Thermoplastic processing is not possible, however very similar fluorine compounds have been developped in recent years which can be processed by injection moulding or extrusion. View ⇒ Perfluoralkoxyl-polymers