Electricity distribution is the final stage in the delivery (before retail) of electricity to end users. A distribution system's network carries electricity from the transmission system and delivers it to consumers. Typically, the network would include medium-voltage (less than 50 kV) power lines, electrical substations and pole-mounted transformers, low-voltage (less than 1 kV) distribution wiring and sometimes electricity meters, as per Wikipedia. EPDM based medium voltage distribution cables have been growing at a healthy pace over the past forty years despite introduction of XLPE insulation cable. This robust growth can be credited partly to the overall healthy market growth for distribution cable, as well as the attribute of EPDM of having a proven record of service life of over 40 years without any failure- as emphasized by most utilities in an effort to lower cable life cycle costs. EPDM cable offers some advantages over XLPE cable. They are: • Longer service life • Better water tree resistance • Better thermal stability at higher operating temperatures • Significantly better flexibility that allows ease of installation under different weather conditions Metallocene-based Vistalon™ EPDM rubber provides added flexibility and improved processability in medium and low-voltage compounds with the inherent metallocene property of cleanliness. ExxonMobil Chemical’s Vistalon™ EPM rubber 722 can improve processing costs and cable flexibility in medium- and low-voltage wire and cable applications. Compared to conventional EPDM, this metallocene-based product can provide processing improvements while exhibiting similar performance. It offers improved flexibility at low temperatures compared with cross-linked polyethylene (PE). Cables with this EPM rubber have passed long-term electrical tests (AEIC). Vistalon EPDM exhibits: • Excellent flexibility to ease installation in narrow or winding pathways even in cold conditions • Inherent water-treeing resistance for long service life • Excellent wet electrical properties • Fast cure rates for higher line speeds With these characteristics, it is well suited for use in medium-and low-voltage insulation for power cables, halogen-free cable jackets, molded connectors, cable fillers. Compounds formulated with Vistalon™ EPDM offer processing and final product performance beyond the capabilities of natural and general purpose synthetic rubbers in a variety of applications. Both metallocene- and Ziegler-Natta-based Vistalon EPDM provide added flexibility and improved processability in a wide range of compositions and molecular weights. These compounds offer ozone, heat and electrical resistance; weathering stability; a wide durometer range; and low-temperature flexibility. Vistalon EPDM compounds are well suited for formulations requiring resistance to steam, temperature and water; and where oil resistance is not required. This EPM copolymer employs a single-site metallocene catalyst having very high catalyst efficiency, which yields a low catalyst residue level, as well as a unique activator. This catalyst system was specifically designed to optimize MV compound performance and is a significant improvement over previous metallocene EP(D)M polymers for wire and cable applications, as per RubberWorld. In addition, the elimination of slurry aids results in a polymer with low residual ash when compared to conventional Ziegler-Natta polymers. This EPM copolymer demonstrates good crosslinking reactivity with common peroxides, even in the absence of a diene termonomer, which contributes to excellent heat ageing properties. Other desirable attributes include long chain branching, easy incorporation of high filler loadings, improved flexibility over a wide temperature range, and a pelletized form for easier compounding and processing. As such, V722 is an attractive choice for high performance medium voltage insulation compounds. It demonstrates additional characteristics that are common to EP(D)M polymers produced via single-site metallocene catalysts. One key characteristic of metallocene catalysts is their ability to design polymers with a very uniform molecular architecture. As a result, it demonstrates a higher degree of crystallinity than might be expected from its ethylene content (approximately 72%) if it were prepared using a conventional multi-site Ziegler-Natta catalyst system. This is attributed to the ability of metallocene catalysts to incorporate propylene in a more random fashion while ZieglerNatta catalysts tend to incorporate ethylene in a more alternating fashion. When compared to conventional Ziegler-Natta catalysts, metallocene catalysts tend to incorporate longer, more crystallizable ethylene sequences (i.e., the ethylene crystallinity is less disturbed by propylene "defects"), thereby producing EP(D)M polymers having higher crystallinity, which is typically manifested as higher heats of fusion and/or higher melting transition temperatures (Tin).