The invention relates to a polymer composition comprising a polyethylene, a crosslinking agent and antioxidant(s), wherein the polymer composition contains a total amount of vinyl groups which is B vinyl groups per 1000 carbon atoms, and B.sub.1B, wherein B.sub.1 is 0.12, when measured prior to crosslinking according to method ASTM D6248-98, the crosslinking agent is present in an amount which is Z wt %, based on the total amount (100 wt %) of the polymer composition, and Z.sub.1ZZ.sub.2, wherein Z.sub.1 is 0.005 and Z.sub.2 is 2.0, and the antioxidant(s) is/are nitrogen containing antioxidant(s) being present in an amount which is W wt %, based on the total amount (100 wt %) of the polymer composition, and W.sub.1WW.sub.2, wherein W.sub.1 is 0.005 and W.sub.2 is 1.0, an article being e.g. a cable, e.g. a power cable, and processes for producing a polymer composition and an article; useful in different end applications, such as wire and cable (W&C) applications.

Provided are a core electric wire for multi-core cable that is superior in flex resistance at low temperature, and a multi-core cable employing the same. A core electric wire for multi-core cable according to an aspect of the present invention comprises a conductor obtained by twisting element wires, and an insulating layer that covers an outer periphery of the conductor, in which, in a transverse cross section of the conductor, a percentage of an area occupied by void regions among the element wires is from 5% to 20%. An average area of the conductor in the transverse cross section is preferably from 1.0 mm.sup.2 to 3.0 mm.sup.2. An average diameter of the element wires in the conductor is preferably from 40 m to 100 m, and the number of the element wires is preferably from 196 to 2,450. The conductor is preferably obtained by twisting stranded element wires obtained by twisting subsets of element wires. The insulating layer preferably comprises as a principal component a copolymer of ethylene and an -olefin having a carbonyl group.

An insulation or jacket layer for a coated conductor is composed of (A) a crosslinked silane-functionalized polyolefin, (B) a filler, (C) a reactive branched polysiloxane, and (D) from 0.00 wt % to 20 wt % of a silanol condensation catalyst.

A cable is provided having at least one electrically insulating layer obtained from a polymer composition with at least one polypropylene-based thermoplastic polymer material and at least one inorganic filler selected from aluminium oxide, a hydrated aluminium oxide, magnesium oxide, zinc oxide, and a mixture thereof; and a method for making the cable.

An extruded flexible flat cable includes conductors arranged side by side in a width direction of the extruded flexible flat cable, the conductors being spaced away from each other at a regular interval and an insulator provided around the conductors by extrusion molding. A portion of the insulator located between the conductors, the portion having been sampled after the extruded flexible flat cable is subjected to a slide bending test, has a tensile strength being equal to or greater than 47.2 MPa. The portion has a percentage elongation being equal to or greater than 50/(0.5+2R), R being a bend radius [mm] at which the extruded flexible flat cable is bent in the slide bending test.

A coaxial cable with two hour circuit integrity is provided and can include an inner conductor, an outer conductor, an insulating layer disposed between the inner conductor and the outer conductor that includes a polymer support structure and air pockets that act as a dielectric for a signal transmitted through the inner conductor, an outer jacket, and a flame barrier disposed between the outer jacket and the outer conductor to avoid choking the signal, wherein the flame barrier can prevent fire from advancing from the outer jacket to the outer conductor for at least two hours.

A cable can include a cable core surrounded by an outer sleeve having a uniform thickness and further having a first longitudinal section having a first stiffness (e.g., corresponding to a flexible cable), a second longitudinal section having a second stiffness (e.g., corresponding to a rigid cable), and a third longitudinal section between the first and second longitudinal sections, where the second stiffness is greater than the first stiffness and where a stiffness of the third longitudinal section varies between the first stiffness and the second stiffness. The second longitudinal section can provide strain relief for the cable.

An extruded flexible flat cable includes conductors arranged side by side in a width direction of the extruded flexible flat cable. The conductors are spaced away from each other at a regular interval and an insulator is provided around the conductors by extrusion molding. A portion of the insulator located between the conductors, the portion having been sampled after the extruded flexible flat cable is subjected to a slide bending test, has a tensile strength being equal to or greater than 47.2 MPa. The portion has a percentage elongation being equal to or greater than 50/(0.5+2R), where R is a bend radius [mm] at which the extruded flexible flat cable is bent in the slide bending test.

A method of manufacturing hybrid cable applicable in oil wells provides an FIMT, a conductor layer formed by continuous laser welding and cylindrically covered the outer surface of the FIMT, the outer cylindrical surface of the conductor layer being covered with a high temperature resistant insulating layer by a continuous extrusion method or by wrapped helically with insulating tapes around the outer surface of the conductor layer and the external steel tube cylindrically covered the outer surface of the insulating layer. The conductor layer is coaxial with the FIMT, the inner space of the hybrid cable to accommodating excess length of the optical fiber to allow for thermal expansions and tensile stress on the optical cable. The thickness of the insulating layer cylindrically covering the outer surface of the conductor layer is able to be increased, improving the insulating property.

An article of manufacture comprising a first section having a first dielectric material and a second section having a second dielectric material and provided on an outer surface of the first section. The second dielectric material of the second section is more flexible than the first dielectric material of the first section, and the second section comprises elements of an organic material located partially on an outer surface of the second section. A coaxial cable using the article of manufacture and a method of manufacturing of the article are also disclosed.