CABLE WITH FOAMED PLASTIC INSULATION COMPRISING AN ULTRA-HIGH DIE SWELL RATIO POLYMERIC MATERIAL

摘要

An electrical communications element having a foamed plastic insulation extruded about a conductor with said insulation comprising at least one component with no more than 20 % by weight of an ultra-high die swell ratio polymer (UHDSRP), preferably around 15 % by weight. The UHDSRP is defined as greater than 55 % die swell ratio and more preferably greater than 65 % die swell ratio. The insulation also preferably comprises at least a second component with a high degree of stress crack resistance, such that the combination of (minimally) these polymers will yield an insulation layer that has a unique combination of physical properties yielding a high degree of foaming, small uniform cell structure, characteristically lower attenuation, and stress crack resistance capable of withstanding greater than 100 hours at 100~C while coiled at a stress level of 1 times the insulation outside diameter without failure (cracking).