| 摘要 |
<p>Disclosed are propylene-based resin compositions having good impact resistance, good scratch-whitening resistance and good weld appearance with little uneven gloss, and automobile trim members made from the compositions. The composition comprises (A) from 42 to 95 % by weight of a propylene-based resin having an isotactic pentad fraction of at least 95 %, (B) from 1 to 10 % by weight of an ethylene-C3-18 alpha -olefin copolymer having a density of from 0.850 to 0.875 g/cm<3> and a melt index of from 0.01 to 25 g/10 min, and prepared in the presence of a metallocene catalyst, (C) from 2 to 18 % by weight of a high-density polyethylene having a density of from 0.93 to 0.97 g/cm<3> and a melt index of from 0.5 to 10 g/10 min, and (D) from 2 to 35 % by weight of talc, the total of the components (B) and (C) being from 3 to 23 % by weight. In the composition, the component (A) preferably satisfies the following requirements (1) to (4): (1) The propylene-based resin of (A) comprises (a) from 70 to 98 % by weight of a fragment insoluble in paraxylene at 23 DEG C and (b) from 2 to 30 % by weight of a fragment soluble in paraxylene at 23 DEG C. (2) The fragment (a) has a relaxation time, tau , of from 0.01 to 0.35 seconds at an angular frequency, omega , of 10 DEG /sec as obtained through melt viscoelastometry, and has a molecular weight distribution index (PDI) of from 1 to 18, which is represented by omega 2/10 omega 1 where omega 1 indicates an angular frequency at which the modulus of stored elasticity, G', as obtained through melt viscoelastometry is 2 x 10<2> Pa, and omega 2 indicates an angular frequency at which G' is 2 x 10<4> Pa. (3) The fragment (b) has a limiting viscosity Ä eta Ü (in decalin at 135 DEG C) of from 2.0 to 10 dl/g. (4) The ethylene unit content of (A) is from 1 to 17 % by weight. The composition may be injection-molded into automobile trim members.</p> |
