| Polyvinylchloride (PVC) |
|
| Plastic Type | Thermoplastic |
| Melting Point | 90 oC |
| Density | 1,1- 1,35 g/cm3 |
| Tensile Strength | 2,60 N/mm2 |
| Max. Use Temperature | 70 oC |
| Dielectric constant | 2,7-3,0 @1MHz |
| Resistance (ohm/cm) | 1012 - 1015 |
Polyvinylchloride is the most
common,by far, thermoplastic used in cable produciton. From the insulation of
basic single wire household cable to high voltage power cables, PVC is used in
almost every segment and niche in cable production. One major
disadvantage of PVC that it emits Halogen gas in case of fire. Because of this
, it had been replaced by halogen free compounds in tunnels and public
building since mid 1990's.
Early researchers accidentally discovered PVC on at
least two occasions in the 19th century. The first, in 1838, was by French
physicist and chemist Henri Victor Regnault and the second in 1872 by German Eugen
Baumann. On both occasions, the polymer appeared as a white solid inside
flasks of the newly discovered vinyl chloride gas that had been left exposed
to sunlight.
PVC is a versatile polymer. To be used as an insulation material PVC has to be
plasticized. PVC was
first used as cable insulation as a replacement for rubber during the Second
World War, but has now become the superior material through its flexibility,
ease of handling in installation and inherent flame retardation. PVC cables do
not harden and crack over time and find use in many applications from
telecommunications to electric blankets. PVC is recyclable. In European
harmonised coding PVC is shown with the letter "V" as regular soft PVC and
"V2" as high temperature resistant PVC. In VDE coding PVC is shown with
the letter "Y".
References:
http://www.pvc.org/en/p/history