|Cross Linked Polyethylene (XLPE)||
|Melting Temp||150-170 0C|
Polyethylene(PE) is one of
the most common thermoplastic that used in cable production. Cross-linked
Polyethylene is abbreviated either XLPE or PEX. In cable production XLPE
is more common. PE has good electrical properties and a high electric resistivity,
that gives it potential for use at much higher voltages than PVC.
Plus, cross-linking results in better mechanical properties which makes XLPE
the most compatible for cable types rated over 0,60/1 kV and higher.
After cross linking XLPE would not melt down anymore. Thermoset Plastic PE
changed into Thermoset XLPE. Meanwhile, Abrasion resistance, impact
strength, thermal stability, tensile strength and scratch resistance would be
There are a few different ways to cross link polyethylene. Cross-links can be formed by chemical reactions that are initiated by heat, pressure, change in pH, or irradiation. For example, mixing of an unpolymerized or partially polymerized resin with specific chemicals called crosslinking reagents results in a chemical reaction that forms cross-links. Cross-linking can also be induced in materials that are normally thermoplastic through exposure to a radiation source, such as electron beam exposure, gamma radiation, or UV light. For example, electron beam processing is used to cross-link the C type of cross-linked polyethylene. Other types of cross-linked polyethylene are made by addition of peroxide during extruding (type A) or by addition of a cross-linking agent (e.g. vinylsilane) and a catalyst during extruding and then performing a post-extrusion curing.1
Polyethylene was cross linked for the first time in 1930 with electron beam technology. Engel cross-linking was developed in 1960's. Using vinylsilane was developed in 1986.