A method of making an attenuated-light-off post-metallocene catalyst, the method comprising combining a faster-light-off catalyst with an effective amount of a kinetics modifier compound of formula (A.sup.1), (B.sup.1), or (C.sup.1): R5-C≡C—R.sup.6 (A.sup.1), (R.sup.5).sub.2C═C═C(R.sup.6).sub.2 (B.sup.1), or (R.sup.5)(R.sup.7)C═C(R.sup.6)(R.sup.7) (C.sup.1) as defined herein under effective reaction conditions to give an attenuated post-metallocene catalyst that exhibits an attenuated light-off monomer uptake profile (relative to that of the faster-light-off catalyst); wherein the faster-light-off catalyst has been made by activating a post-metallocene precatalyst of structural formula (I) as defined herein; and related methods, compositions and uses.

This invention relates to a supported catalyst system comprising a first iron based catalyst, a second group 4 metal catalyst, a support material, and an activator; wherein the first catalyst is represented by Formula (I) and the second catalyst is represented by Formula (II):

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Disclosed herein are mixed catalyst systems including iron-containing catalyst compounds having a carbene ligand and another catalyst compound, as well as at least one activator. The iron-containing catalyst compounds can be asymmetric, while the other catalyst compound can be symmetric. In some embodiments, the other catalyst compound can be an iron-containing catalyst with a bisiminopyridyl ligand, which does not typically incorporate comonomers in copolymer synthesis. Processes for production of an ethylene alpha-olefin copolymers using these mixed catalyst systems are also disclosed. Ethylene-alpha-olefin copolymers so formed can have at least a portion of their alpha-olefin comonomer distribution increasing with increasing molecular weight, indication orthogonal compositional distribution.