Material Properties
Insulation & Sheath Material Properties Related To Fireproof of Cable

Halogen free
AEI SX545:CM540U General purpose silane crosslinkable HFFR sheathing
Low smoke, low-toxicity, halogen-free, flame-retardant, silane crosslinkable compound
for insulation of LV cables and sheathing of all types of cables

Extruder
Many modern thermoplastic extruders will process the material, although a screw designed to give good
homogenisation without excessive shear (which could cause unacceptable increases in melt temperature) should be used. An extruder with an L/D ratio (length/diameter) of 15-24 and an extruder screw with a compression ratio 1.2:1 are recommended.
Extruder temperature conditions
It is important that the melt temperature is not allowed to increase above 170ºC. As a guide the following temperature profile is recommended:-

This profile will vary slightly depending on extruder type, head design and output.
Screw water temperature40-60°C
Recommended screen pack: 50 (mesh apertures per linear inch) or 300 micron
Crosslinking or Cure
A satisfactory cure can be obtained either by immersion in hot water or exposure to low pressure steam at a temperature up to 65°C.
Catalyst and Colour Masterbatches
CM540U catalyst masterbatch is normally added at 5% to 95% of the SX545 graft.
Addition of approved colour masterbatches, including black, up to a maximum of 1%, has no detrimental effect on the properties or crosslinking capability.
It is recommended that all masterbatches including those containing the catalyst should be thoroughly dried before use for 8 hours at 60°C or 4 hours at 80°C in a de-humidifying drier.
Storage and Shelf Life
SX545 normally has shelf life of at least 6 months from the date of manufacture. The storage of silane crosslinkable
compounds in cool dry conditions will maximise useful shelf life. Other precautions are:-
• Packaging should remain sealed.
• Avoid temperature above 25°C.
• Avoid storage outside and in direct sunlight.
• Use within 8 hours of opening packaging.