DYNAMIC LOAD RESISTANT POLYOLEFIN COMPOSITIONS Russian patent published in 2009 - IPC C08L23/10 C08F2/00 C08F10/00 

FIELD: chemistry.

SUBSTANCE: invention relates to polyolefin composition which are resistant to dynamic loading and to the method of producing said composition. The composition contains A) 60 to 95 wt % propylene (co)polymer of with polydispersity index (P.I) from 4.6 to 10 and isotactic pentad content (mmmm) over 98 mol %, determined using ¹³C-NMR spectroscopy for a fraction which is insoluble in xylene at 25°C and B) 5 to 40 wt % ethylene copolymer, containing 40 to 70 wt % propylene or C₄-C₁₀ α-olefins or their combination and, optionally, small diene proportions. The composition has temperature rising elution fractionation (TREF) profile, obtained through fractionation in xylene with tapping fractions at temperature 40°C, 80°C and 90°C, in which ethylene content Y in the fraction tapped at 90°C satisfies relationship (I): Y≤-0.8+0.035X+0.0091X², where X is ethylene content in the fraction tapped at 40°C, and both values of X and Y are expressed in weight percent, and value of intrinsic viscosity [η] of the fraction which is soluble in xylene at 25°C ranges from 1.8 to 4.2 dl/g.

EFFECT: obtaining olefin polymer with good balance of properties, more specifically with high hardness and good resistance to dynamic loading.

3 cl, 3 ex, 3 tbl