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

Halogen free
AEI SX738:CM424 Silane crosslinkable HFFR for flexible heatshrink tubing
Low-smoke, low-toxicity, halogen-free, flame retardant, silane crosslinkable compound for
the production of flexible heat shrinkable tubing

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 of compression ratio 2-3:1 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 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 65ºC
Catalyst and Colour Masterbatches
CM424 catalyst masterbatch is normally added at 5% to 95% of SX738 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 for 4 hours at 80°C.
Storage & Shelf Life
SX738 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.