The invention is an
electrically conductive device, e.g., a wire or cable, having a crush resistance of at least about 18
pounds per square inch (psi), the device comprising: A. An
electrically conductive member comprising at least one
electrically conductive substrate, e.g., a wire strand or a pair of twisted wire strands; and B. At least one electric-insulating member substantially surrounding the electrically conductive member, e.g., a
polymer coating or layer, the electric-insulating member comprising a
polymer blend, the
polymer blend comprising: 1. At least about 50 weight percent of a
polypropylene, and 2. At least about 10 weight percent of an
elastomer. In one embodiment, the blend is characterized as having (i) a hot
creep of less than 200% at 150 C, (ii) a
dielectric constant at 60 Hz and 90 C of less than about 2.5, (iii) a
dissipation factor at 60 Hz and 90 C of less than about 0.005, and (iv) an AC
breakdown strength of greater than about 600 v / mil.