High flow thermoplastic polyolefin with balanced mechanical performance and low shrinkage and CLTE

摘要

This invention relates to a thermoplastic polyolefin composition having a melt flow rate MFR2 (230° C.) between 20 and 100 g/10 min, to the use of such thermoplastic polyolefin composition for the production of injection molded articles, e.g. automotive parts and to injection molded articles prepared by using such thermoplastic polyolefin composition.

主权项

1. A thermoplastic polyolefin (TPO) composition having a melt flow rate MFR2 (230° C.) between 20 and 100 g/10 min measured according to ISO 1133, comprising
a) a matrix phase (M) comprising a propylene homopolymer (H-PP) and/or a propylene copolymer (R-PP), and b) a dispersed phase (D) comprising an ethylene-C3-C8-α-olefin rubber copolymer (EOP), wherein (i) the composition comprises 20 wt.-% to 45 wt.-%, based on the total weight of the composition, of a xylene cold soluble (XCS) fraction having
(i-a) an ethylene content in the range of 40 wt.-% to 65 wt.-%, and(i-b) an intrinsic viscosity (IV) of below 1.5 dL/g measured according to ISO 1628, and (ii) the ratio of the intrinsic viscosity (IV) of xylene cold insoluble (XCI) fraction to the intrinsic viscosity (IV) of the xylene cold soluble (XCS) fraction ([XCS]/[XCI]) of the thermoplastic polyolefin (TPO) composition is in the range of 0.75 to 1.35, and wherein the composition comprises (a) 30 wt.-% to 45 wt.-%, based on the total weight of the composition, of the ethylene-C3-C8-α-olefin rubber copolymer (EOP).