| 摘要 |
PURPOSE:To obtain the titled composition having improved extrusion moldability and especially injection moldability, and excellent mechanical property and impact resistance, by compounding a polypropylene resin with a specific ethylene-propylene copolymer rubber. CONSTITUTION:The objective composition can be prepared by compounding (A) 5-50wt% of an ethylene-propylene copolymer rubber wherein the ratios (wt%) of (ethylene):(propylene):(conjugated diene) are (15-70):(30-85):(0-15), the ratio of the weight average molecular weight Mw to the number average molecular weight Mn (Mw/Mn) is 4-18, the heat of fusion between 100 deg.C and 140 deg.C is <=1cal/g measured by differential thermal analysis, the difference between the propylene content in the low-molecular weight part accounting for 15wt% of the whole polymer (a%) and the propylene content in the high molecular weight part accounting for 15wt% of the whole polymer (b%), i.e. a-b, is >10, and the content of the inversely bonded propylene is <=5mol%, with (B) 50-95wt% of a propylene homopolymer or a copolymer of propylene containing <=20wt% of ethylene.
|
