POLYOLEFIN COMPOSITION SHOWING GOOD BALANCE OF RIGIDITY AND IMPACT RESISTANCE CHARACTERISTICS Russian patent published in 2004 - IPC

FIELD: polymer materials. SUBSTANCE: invention relates to elastomer composition based on thermoplastic polyolefin, in particular to composition containing polypropylene with wide molecular weight distribution, used in automobile industry for manufacturing bumpers and side bands. Composition comprises 40 to 60% of polypropylene with polydispersity index 5-15 and melt flow speed 80-200 g/10 min (according to ASTM- D 1238, clause L) and 40 to 60% of partially xylene-insoluble polyolefin rubber containing at least 65 wt % if ethylene units. Ratio of intrinsic viscosity value of xylene-soluble (at room temperature) portion of polyolefin composition to the value of intrinsic viscosity of polypropylene component within a range of 2 to 2.5, intrinsic viscosity values being measured in tetrahydronaphthalene at 135 C. EFFECT: improved combination of physicochemical properties, in particular combination of elasticity modulus and Isod impact resistance, including those at low temperatures. 8 cl, 2 tbl, 4 ex