Patent ID: 7863379

Claim:
A composition comprising: A) a thermoplastic polymer composition, and B) an impact modifying amount of an ethylene/Î±-olefin multi-block interpolymer polymerized in the presence of a catalyst composition comprising a first olefin polymerization catalyst having a first comonomer incorporation index, a second olefin polymerization catalyst having a second comonomer incorporation index different than the first comonomer incorporation index, and a chain shuttling agent, wherein the ethylene/Î±-olefin interpolymer comprises at least 50 mole percent ethylene and: (a) has a Mw/Mn from about 1.7 to about 3.5, at least one melting point, Tm, in degrees Celsius, and a density, d, in grams/cubic centimeter, wherein the numerical values of Tm and d correspond to the relationship: Tm>âˆ’ 2002.9+4538.5( d )âˆ’2422.2( d ) 2 ; and either: (b) has a Mw/Mn from about 1.7 to about 3.5, and is characterized by a heat of fusion, Î”H in J/g, and a delta quantity, Î”T, in degrees Celsius defined as the temperature difference between the tallest DSC peak and the tallest CRYSTAF peak, wherein the numerical values of Î”T and Î”H have the following relationships: Î” T>âˆ’ 0.1299(Î” H )+62.81 for Î” H greater than zero and up to 130 J/g, Î”â‰§48Â° C. for Î” H greater than 130 J/g, wherein the CRYSTAF peak is determined using at least 5 percent of the cumulative polymer, and if less than 5 percent of the polymer has an identifiable CRYSTAF peak, then the CRYSTAF temperature is 30Â° C.; or (c) is characterized by an elastic recovery, Re, in percent at 300 percent strain and 1 cycle measured with a compression-molded film of the ethylene/Î±-olefin interpolymer, and has a density, d, in grams/cubic centimeter, wherein the numerical values of Re and d satisfy the following relationship when the ethylene/Î±-olefin interpolymer is substantially free of a cross-linked phase: Re> 1481âˆ’1629( d ); or (d) has a molecular fraction which elutes between 40Â° C. and 130Â° C. when fractionated using TREF, characterized in that the fraction has a molar comonomer content of at least 5 percent higher than that of a comparable random ethylene interpolymer fraction eluting between the same temperatures, wherein said comparable random ethylene interpolymer has the same comonomer(s) and has a melt index, density, and molar comonomer content (based on the whole polymer) within 10 percent of that of the ethylene/Î±-olefin interpolymer.