ELASTOMERIC COMPOUND

摘要

The invention relates to an elastomeric compound comprising at least one olefinic elastomer comprising ethylene, an a-olefin, from 1 to 7 wt% vinyl norbornene and from 0 to 15 wt% of a second non-conjugated polyene, wherein the wt% are related to the total weight of ethylene, a-olefin, vinyl norbornene and the second non-conjugated polyene, and which elastomer has long chain branching corresponding with ?d <20, wherein ?d, expressed in degrees, is calculated from the difference between the phase angle d between stress and strain in a dynamic shear measurement at 125°C at a frequency of 0.1 rad/s and the phase angle d at a frequency of 100 rad/s and the compound further comprising a solid filler and an oil, such that the compound has a compound loading between 120 and 300 phr, wherein said olefinic elastomer satisfies the following relation S<SUB>b</SUB> > 30, wherein S<SUB>b</SUB> is the slope in a graph of ln(a<SUB>c</SUB>) versus F, in which a<SUB>c</SUB> is the factor along which the low frequency part (? < 1 rad/s) of the phase angle d versus ? plots, measured at at least one volume fraction F between 0.2 and 1 of the olefinic elastomer in squalane, must be shifted to coincide with a d versus ? plot of an undiluted polymer (F =1), and wherein the d versus ? plots results from a frequency sweep performed on a stress controlled rheometer carried out at 125 °C under nitrogen atmosphere, using a parallel plate geometry in shear. The invention further relates to a method for the preparation of the compound of the invention.