Abstract: A multimode optical fiber for continuous transmission of electromagnetic radiation at high power, wherein the fiber defines a fiber axis and includes a core and a cladding surrounding the core, and wherein the multimode optical fiber is a multimode graded-index fiber, the refraction index profile in the fiber essentially following formula (1): n ? ( r ) = { n 1 ? [ 1 - 2 ? ( r a ) g ? ? ] 1 ? / ? 2 , r < a n 2 , r > a ( 1 ) ? = n 1 2 - n 2 2 2 ? n 1 2 ( A ) NA = n 1 2 - n 2 2 ( B ) where ? is formula (A), r is the distance from the fiber axis, n(r) is the nominal refractive index as a function of distance from the fiber axis, n1 is the nominal refractive index on the axis of the fiber, n2 is the refractive index of the cladding, a is the core radius, and g is a parameter that defines the shape of the profile, where the core diameter 2a is between 90 UM and 190 ?M, the parameter g is between 1.

Abstract: A multimode optical fiber for continuous transmission of electromagnetic radiation at high power, wherein the fiber defines a fiber axis and includes a core and a cladding surrounding the core, and wherein the multimode optical fiber is a multimode graded-index fiber, the refraction index profile in the fiber essentially following formula (1): n ? ( r ) = { n 1 ? [ 1 - 2 ? ( r a ) g ? ? ] 1 ? / ? 2 , r < a n 2 , r > a ( 1 ) ? = n 1 2 - n 2 2 2 ? n 1 2 ( A ) NA = n 1 2 - n 2 2 ( B ) where ? is formula (A), r is the distance from the fiber axis, n(r) is the nominal refractive index as a function of distance from the fiber axis, n1 is the nominal refractive index on the axis of the fiber, n2 is the refractive index of the cladding, a is the core radius, and g is a parameter that defines the shape of the profile, where the core diameter 2a is between 90 UM and 190 ?M, the parameter g is between 1.

Abstract: The present invention is an improved electric insulation composition of a polymer and an additive that reduces water treeing due to electrical aging in water. The polymer additive is a hydrophobic/hydrophilic material with good compatibility with the polymer. The present invention is also a method of preventing electrical breakdown due to the formation of water trees by forming electrical cables with the insulation containing the disclosed anti-treeing additives.

Abstract: The present invention is an improved electric insulation composition of a polymer and an additive that reduces water treeing due to electrical aging in water. The polymer additive is a hydrophobic/hydrophilic material with good compatibility with the polymer. The present invention is also a method of preventing electrical breakdown due to the formation of water trees by forming electrical cables with the insulation containing the disclosed anti-treeing additive.

Abstract: A polymeric composition for coating electric cables for power transmission at medium/high voltage, having an improved resistance against the formation of the so-called water trees, comprises a polymeric polyolefin base including, in parts by weight to the total weight thereof, from 0.5 to 15 parts of ester groups and from 0.01 to 5 parts of epoxy groups. Electric cables according to the invention comprise at least one electrically conducting core (2) and an insulation coating (5) comprising the aforementioned polymeric composition.

Abstract: A polymeric composition for coating electric cables for power transmission at medium/high voltage, having an improved resistance against the formation of the so-called water trees, comprises a polymeric polyolefin base including, in parts by weight to the total weight thereof, from 0.5 to 15 parts of ester groups and from 0.01 to 5 parts of epoxy groups. Electric cables according to the invention comprise at least one electrically conducting core (2) and an insulation coating (5) comprising the aforementioned polymeric composition.

Abstract: A polymeric composition for coating electric cables for power transmission at medium/high voltage, having an improved resistance against the formation of the so-called water trees, comprises a polymeric polyolefin base including, in parts by weight to the total weight thereof, from 0.5 to 15 parts of ester groups and from 0.01 to 5 parts of epoxy groups. Electric cables according to the invention comprise at least one electrically conducting core (2) and an insulation coating (5) comprising the aforementioned polymeric composition.

Abstract: A polymeric composition for coating electric cables for power transmission at medium/high voltage, having an improved resistance against the formation of the so-called water trees, comprises a polymeric polyolefin base including, in parts by weight to the total weight thereof, from 0.5 to 15 parts of ester groups and from 0.01 to 5 parts of epoxy groups. Electric cables according to the invention comprise at least one electrically conducting core (2) and an insulation coating (5) comprising the aforementioned polymeric composition.