| 摘要 |
<p>The invention relates to an elastomeric compound comprising at least one olefinic elastomer comprising ethylene, anα-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,α-olefin, vinyl norbornene and the second non-conjugated polyene, and which elastomer has long chain branching corresponding withΔδ< 20, whereinΔδ, expressed in degrees, is calculated from the difference between the phase angleδbetween stress and strain in a dynamic shear measurement at 125°C at a frequency of 0.1 rad/s and the phase angleδat 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 Sb > 30, wherein Sb is the slope in a graph of ln(ac) versusΦ, in which ac is the factor along which the low frequency part (ω< 1 rad/s) of the phase angleδversusωplots, measured at at least one volume fractionΦbetween 0.2 and 1 of the olefinic elastomer in squalane, must be shifted to coincide with aδversusωplot of an undiluted polymer (Φ=1), and wherein theδversusωplots 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.</p> |
