The invention is directed to essentially saturated
hydrocarbon polymer composition comprising essentially saturated
hydrocarbon polymers having A) a
backbone chain, B) a plurality of essentially hydrocarbyl sidechains connected to A), said sidechains each having a number-average molecular weight of from 2500 Daltons to 125,000 Daltons and a MWD by SEC of 1.0-3.5; and having A) a Newtonian limiting
viscosity (eta0) at 190° C. at least 50% greater than that of a linear olefinic
polymer of the same
chemical composition and weight average molecular weight, preferably at least twice as great as that of said
linear polymer, B) a ratio of the rubbery
plateau modulus at 190° C. to that of a
linear polymer of the same
chemical composition less than 0.5, preferably <0.3, C) a ratio of the Newtonian limiting
viscosity (eta0) to the absolute value of the complex
viscosity in oscillatory shear (eta*)at 100 rad / sec at 190° C. of at least 5, and D) a ratio of the
extensional viscosity measured at a
strain rate of 1 sec-1, 190° C., and time=3 sec (i.e., a strain of 3) to that predicted by linear
viscoelasticity at the same temperature and time of 2 or greater.
Ethylene-
butene prepared by anionic
polymerization and hydrogenation illustrate and
ethylene-
hexene copolymers prepared by
coordination polymerization illustrate the invention. The invention polymers exhibit improved
processing characteristics in that the
shear thinning behavior closely approaches that of ideal polymers and exhibit improved strain thickening.