ALPHA-NUCLEATED POLYPROPYLENE FOR POWER CABLE INSULATION

摘要

The present invention relates to a heterophasic polymer composition, comprising (i) a matrix which comprises a propylene copolymer or a blend of two or more propylene copolymers, wherein the propylene copolymer or the blend of propylene copolymers represents at least 85 wt% of the matrix and comprises comonomer units derived from ethylene and/or a C4-12 alpha-olef?n, and (ii) an elastomeric propylene copolymer which is dispersed within the matrix and comprises comonomer units derived from ethylene and/or a C4-I2 alpha-olefm; (iii) a polymeric alpha-nucleating agent which comprises monomer units derived from a vinyl compound of the following chemical formula (I) wherein R1 and R2 independently represent a substituted or unsubstituted alkyl, cycloalkyl or aryl, or R1 and R2 together form a saturated, unsaturated or aromatic ring system; the heterophasic polymer composition further having (iv) a xylene cold soluble fraction of at least 15 wt%.