Abstract: The present invention relates to a method for preparing an unsaturated ethylene-diene copolymer by high pressure radical-initiated polymerisation, said method providing an improved conversion of added diene into pendant vinyl groups.

Abstract: The present invention relates to a crosslinkable polymer composition, comprising (i) an unsaturated polyolefin having a total amount of carbon-carbon double bonds/1000 carbon atoms of more than 0.37, and (ii) at least one ether and/or ester group containing additive selected from the group consisting of polyethylene glycol, a glycerol ester compound, polypropylene glycol, an amido group containing fatty acid ester, ethoxylated and/or propoxylated pentaerythritol, an alpha-tocopherol ester, an ethoxylated and/or propoxylated fatty acid, and derivatives thereof.

Abstract: The present invention relates to a crosslinkable polymer composition, comprising (i) a polyolefin, (ii) a polar copolymer, and (iii) a glycerol ester compound.

Abstract: The present invention relates to a crosslinkable polymer composition, comprising (i) an unsaturated polyolefin having a total amount of carbon-carbon double bonds/1000 carbon atoms of more than 0.

Abstract: The invention relates to a polymer composition, comprising (a) a polyolefin base resin which comprises at least (a1) a first olefin homo- or copolymer fraction, and (a2) a second olefin homo- or copolymer fraction, wherein the weight average molecular weight of the first fraction is lower than the weight average molecular weight of the second fraction, and (b) at least one additive selected from a polar copolymer; a low density polyethylene; an ether and/or ester group containing additive selected from the group consisting of polyethylene glycol, a glycerol ester compound, polypropylene glycol, an amido group containing fatty acid ester, ethoxylated and/or propoxylated pentaerythritol, an alpha-tocopherol ester, an ethoxylated and/or propoxylated fatty acid, and derivatives thereof; or mixtures of these additives.

Abstract: The present invention relates to an insulating composition for an electric power cable which comprises a polyolefin, an antioxidant, and a polar copolymer. Further, the present invention relates to an electric power cable comprising an insulating layer including a composition according to the present invention, and to the use of a polar copolymer for improving the storage stability, i.e. reducing the exudation of an antioxidant, in an insulating polymer composition. Thereby, said composition comprises polar monomer units in a comparatively small amount, e.g. in an amount of polar monomer units in the total polymer part of the composition from 1 to 100 micromol (1·10?6 to 100·106 mol) per gram of polymer in addition to an antioxidant.

Abstract: The present invention relates to crosslinkable polymer composition, comprising an unsaturated polyolefin having a total amount of carbon-carbon double bonds/1000 carbon atoms of at least 0.1, at least one scorch retarder, and at least one crosslinking agent.

Abstract: The invention relates to a semiconductive polymer composition for use in power cables. The composition comprises a multimodal ethylene homo- or copolymer produced in a polymerisation process comprising a single site catalyst whereby the polymer composition has a density of 870 to 930 kg/m3, a MFR2 of 1 to 30 g/10min and a Mw/Mn of less than or equal to 10.

Abstract: The present invention relates to a process for preparing a crosslinked polymer composition, comprising the steps: (a) preparing a crosslinkable blend of a crosslinking agent and an unsaturated polyolefin having a total amount of carbon-carbon double bonds/1000 carbon atoms of more than 0.37, wherein the blending step is carried out prior to and/or during extrusion of the unsaturated polyolefin, and the crosslinking agent is in a liquid state when it comes into contact with the unsaturated polyolefin, (b) extruding the blend in an extruder, (c) applying the extruded blend onto a substrate, and (d) treating the extruded blend under crosslinking conditions.

Abstract: The present invention relates to a semiconductive polymer composition comprising a olefin homo- or copolymer wherein the composition has a direct current volume resistivity of less than 1000 Ohm.cm at 90 ° C., an elongation at break which after aging for 240 hours at 135 ° C. does not change by more than 25%, and a total number of structures of 20 or less in the SIED test. Furthermore, the present invention relates to an electric power cable comprising a conductor, a semicoducting layer and, adjacent to the semiconducting layer, an insulation layer, wherein the semiconducting layer is formed by said semiconductive polymer composition and to the use of said semiconducting polymer composition for the production of a semiconductive layer of an electric power cable.

Abstract: The invention relates to a semiconductive polymer composition for use in power cables. The composition comprises a multimodal ethylene homo- or copolymer produced in a polymerisation process comprising a single site catalyst whereby the polymer composition has a density of 870 to 930 kg/m3, a MFR2 of 1 to 30 g/10 min and a Mw/Mn of less than or equal to 10.

Abstract: The present invention relates to a stabilizing agent for polymers or copolymers which is a copolymer of ethylene or propylene (A) and a vinyl compound (B) having the formula: wherein X is O, NH or NR5; R1, R2 and R3 are each independently H, C1-C8 alkyl, C1-C8 substituted aryl; R4 is H, C1-C8 alkyl, C6-C12 cycloalkyl, C1-C10 acyl, C1-C10 acyloxy or C1-C8 alkyl ether; R5 is C1-C8 alkyl and wherein the copolymer has at least 1 mol % (B) and has an MFR2 of 1-1000 g/10 min.

Abstract: An insulating composition for an electric power cable, and an electric power cable that includes a conductor surrounded by an inner semiconducting layer, an insulating layer, and an outer semiconducting layer, where the insulating layer consists of said insulating composition. The insulating composition is characterized in that the ethylene polymer is a multimodal ethylene copolymer obtained by coordination catalyzed polymerization of ethylene and at least one other alpha-olefin in at least one stage, said multimodal ethylene copolymer having a density of 0.890-0.940 g/cm3, a MFR2 of 0.1-10 g/10 min, a MWD of 3.5-8, a melting temperature of at most 125° C., and a comonomer distribution as measured by TREF, such that the fraction of copolymer eluted at a temperature higher than 90° C. does not exceed 10% by weight, and the multimodal ethylene copolymer includes an ethylene copolymer fraction selected from (a) a low molecular weight ethylene copolymer having a density of 0.900-0.

Abstract: The present invention relates to a stabilizing agent for polymers or copolymers which is a copolymer of ethylene or propylene (A) and a vinyl compound (B) having the formula: 1

Abstract: A composition for an insulating layer of an electric cable wherein the composition contains an ethylene plastic as the base resin and further contains up to about 5% by weight of additives including antioxidant, and peroxide cross-linking agent. The composition is characterised in that the antioxidant additive includes a compound of the formula (V): R1(—(C+O)O—)k(CH2)1—S—(CH2)m(—OO(C═O)—)nR2 where R1 and R2, which are the same of different, are C7-C23 alkyl, C7-C23 alkenyl, R3—Ar—, Ar—R3—, or AR—, where R3 is C8-C24 alkyl and Ar is c6-c14 aryl; k and n, which are the same of different, are 0 or 1, l and m, which are the same or different, are integers ≧0; with the proviso that the compound is free from phenolic groups; and that the compositions is free from compounds having the formula (VI): R—O—(C═O)—CH2CH2SCH2CH2—(C═O)—O—R where R is a C8-C20 alkyl group.