Visico LE4421/LE4437 is a scorch retardant, moisture-crosslinking polyethylene compound for low voltage insulation

The combination of a VISICO base material, LE4421, and a tin catalyst masterbatch, LE4437, provides a highly scorch retardant compound with excellent thermal stability. LE4421/LE4437 contains a patented scorch retardant additive (SRA) that increases the processing window for a moisture crosslinking compound and minimizes the tendency for premature crosslinking in the extruder, head or die. LE4437 should be added to LE4421 directly in the extruder hopper by dry blending a ratio of 5 parts LE4437 to 95 parts LE4421. LE4437 also provides, in addition to catalyst, a stabilizaton package containing suitable antioxidants, a metal passivator and a metal deactivator and a 25% loading of fine particle size carbon black for UV weather resistance. Properly mixed, during the extrusion process, LE4421/LE4437 exhibits excellent thermal stability to oxidation. The final insulation or jacketing will also contain 2.5% of a suitable carbon black to ensure satisfactory UV weathering stability.

LE4421/LE4437 is readily pigmented to a variety of colors using standard wire & cable concentrates designed for thermoplastic or crosslinked polyethylene. UV weather resistance is obtained by the addition of a suitable carbon black or UV additive. Using VISICO LE4432 in place of LE4437 combines a tin catalyst along with the proper carbon black to provide a black, UV resistant, moisture crosslinking cable insulation.

APPLICATION:

LE4421/LE4437 is recommended for use as insulation for low voltage conrol cables and power cables up to 6kv in rating.

Specifications
Visico LE4421/LE4437 in combination meets the applicable requirements as below when processed using sound extrusion and testing procedure:

• Underwriters Laboratories Standards 854 for types USE and USE-2

• NF C33-210

• HD 603 S1

• ASTM D 2655

• Canadian Standards Association C22.2 No. 1790-00-AirportSeries Lighting Cables and C22.2 No. 38 Cable Type RW-90 Outdoor

• EC 502

• NBN C 33-321