الفهرس 
: ETHYLENE VINYL ACETATE AS AOnly 14 pages are availabe for public view
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Abstract
High technological age is to a high extend due to the reliability
achieved in the transmission and distribution of power.
Cables are one of the key elements in the hierarchy of the
system. Extending the life of the cables is an important factor on
keeping the system safe and functioning.
Power cables are provided with layers of coatings that are
extruded on the conductor to provide protection and to extend
the life of the cable.
In particular, high voltage power cables have an inner
semiconducting layer (referred to as conductor shield)
surrounding the conductor, an intermediate layer insulation and
an outer semiconducting layer surrounding the insulation layer
(referred to as insulation shield). The purpose of the inner
semiconducting layer is to relax or relief the heterogeneous
electrical stress attributed to irregularities in the conductor and
insulation. The external semiconducting layer, which could
either be a bonded layer or a strippable layer, homogenizes the
electrical stress on the insulation surface.
The semiconducting layer, which is also known as the conductor
shield, is typically formed from ethylene based polymers
(ethylene vinyl acetate or ethylene ethyl acrylate or ethylene
alkene copolymers). The ethylene based polymer is blended on
conducting carbon black as furnace black or acetylene black,
appropriate antioxidants and an organic peroxide cross-linking
agent