Copolymer composition for semiconductive cable layer

A composition for a semi conductive layer of a cable, comprising

• (a) a heterophasic copolymer consisting of a propylene homopolymer or random propylene ethylene copolymer matrix and a propylene copolymer with ethylene, wherein the heterophasic copolymer has a melt flow rate (230° C., 2.16 kg) of from 0.05 to 20.0 g/10 min,
• (b) a polar copolymer comprising ethylene and at least one polar comonomer bearing a polar group, the polar comonomer being selected from C1- to C6-alkyl acrylates, C1- to C6-alkyl methacrylates, acrylic acids, methacrylic acids and vinyl acetate, wherein the polar copolymer has a density of from 900 kg/m3 to 945 kg/m3,
• (c) a solid conductive filler and, optionally,
• (d) a polyolefin functionalised with a mono- or polycarboxylic acid compound or a derivative of a mono- or polycarboxylic acid compound, wherein said mono- or polycarboxylic acid compound or a derivative of a mono- or polycarboxylic acid compound is other than the polar comonomer(s) present in the polar copolymer (b);
• and wherein the composition has a Charpy Notch Impact Strength of at least 10 kJ/m2 at −20° C., measured in accordance with ISO 179-1eA:2000.