| CPC C08L 23/06 (2013.01) [C08L 23/16 (2013.01)] | 12 Claims |
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1. A polymer composition comprising:
an interpolymer of ethylene, an α-olefin, and a nonconjugated polyene; and
from 25% to 35% by weight oil, based on the total weight of the polymer composition; wherein:
the interpolymer comprises:
from 66% to 75% by weight monomer units derived from ethylene, based on the total weight of the interpolymer; and
from 3.5% to 5.5% by weight monomer units derived from the nonconjugated polyene, based on the total weight of the interpolymer;
the interpolymer has:
a weight-average molecular weight Mw from 250 kDa to 300 kDa; and
a polydispersity index from 2.0 to 3.5;
the polymer composition has:
a Mooney viscosity [ML (1+4); 125° C.] from 40 to 55;
a rheology ratio V0.1/V100 from 20 to 25, where
V0.1 (low-shear viscosity) is the viscosity of the polymer composition measured at 190° C. at a frequency of 0.1 radians/second and V100 is the viscosity of the polymer composition measured at 190° C. at a frequency of 100 radians/second;
a ratio of the weight-average molecular weight Mw to the low-shear viscosity V0.1 of the polymer composition, Mw/V0.1, from 4.0 to 5.0 (g/mol)/(Pa·s); and
a tan δ at 0.1 rad/s and 190° C. from 2.1 to 2.3; and
pellets formed from the polymer composition and coated with 5000 ppm talc filler, based on a combined weight of the pellets and the talc filler, have an unconfined yield strength (UYS) of:
less than 500 lb/ft2 when UYS is measured at an unloading temperature of 22° C.; and
less than 1500 lb/ft2 when UYS is measured at an unloading temperature of 0° C.
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