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

Halogen free
AEI SX538:CM540U High fire performance silane crosslinkable HFFR sheathing
Low-smoke, low-toxicity, halogen-free, flame-retardant, silane crosslinkable compound for low voltage insulation and sheathing of all types of cable

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
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 & 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 SX538 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 at 60°C for 8 hours or at 80°C for 4 hours.
Storage and shelf life
SX538 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.