Resin composition, method of making it and electrical wire covered with it

A method of preparing a resin composition, comprising thoroughly mixing the following components:

• (a) 30-80 parts by weight of a polyolefin thermoplastic elastomer having a melting point of at least 130° C. and a Shore A hardness of not more than 90,
• (b) 1-20 parts by weight of a polypropylene modified with 0.1-10% by weight of an acid anhydride,
• (c) 5-50 parts by weight of a styrene-based polymeric elastomer,
• (d) 10-30 parts by weight of a propylene polymer, having a melt flow rate of 0.1-5 g/10 min, measured using a load of 2.16 kgf at 230° C., and selected from propylene homopolymers and propylene-ethylene copolymers having a propylene content of at least 50% by weight, and
• (e) 30-200 parts by weight of a metal hydroxide, based on 100 parts by weight of the resin components,
• wherein a total amount of components (a), (b), (c) and (d) is 100 parts by weight and provided that substantially no other resin component is included in the composition.

An electrical wire having an electrically conductive core and a covering on the core composed of a resin composition comprising the following resin components:

• (a) 30-80 parts by weight of a polyolefin thermoplastic elastomer having a melting point of at least 130° C. and a Shore A hardness of not more than 90,
• (b) 1-20 parts by weight of a polypropylene modified with 0.1-10% by weight of an acid anhydride,
• (c) 5-50 parts by weight of a styrene-based polymeric elastomer, and
• (d) 10-30 parts by weight of a propylene polymer, having a melt flow rate of 0.1-5 g/10 min, measured using a load of 2.16 kgf at 230° C., and selected from propylene homopolymers and propylene-ethylene copolymers having a propylene content of at least 50% by weight,
• wherein a total amount of the components (a), (b), (c) and (d) is 100 parts by weight and provided that substantially no other resin component is present in the resin composition,
• said resin composition further comprising
• (e) 30-200 parts by weight of a metal hydroxide, based on 100 parts by weight of the resin components.