Dual metallocene catalyst copolymer compositions

A process comprising:

• (a) carrying out a polymerization reaction that comprises polymerizing a plurality of monomers comprising (i) a first C2-C20 α-olefin monomer;
• (ii) a second C2-C20 α-olefin monomer different from the first;
• and optionally (iii) one or more dienes in the presence of both a first metallocene catalyst and a second metallocene catalyst in a polymerization reaction zone;
• wherein the first metallocene catalyst has structure in accordance with Formula (I):
• where (1) J is a divalent bridging group comprising C, Si, or both;
• (2) M is a group 4 transition metal;
• (3) each X is independently a univalent anionic ligand, or two Xs are joined and bound to the metal atom to form a metallocycle ring, or two Xs are joined to form a chelating ligand, a diene ligand, or an alkylidene ligand;
• and (4) each R″1-R″10 is independently hydrogen, C1-C50 hydrocarbyl, substituted hydrocarbyl, halocarbyl, or substituted halocarbyl provided that any one or more of the pairs R″1 and R″2, R″3 and R″4, R″5 and R″6, R″6 and R″7, R″8 and R″9, and R″9 and R″10, may optionally be bonded together to form a saturated or partially saturated cyclic or fused ring structure;
• further wherein the second metallocene catalyst has structure in accordance with Formula (II):
• where:
• (1) J is a divalent bridging group comprising C, Si, or both;
• (2) each X is independently a univalent anionic ligand, or two Xs are joined and bound to the metal atom to form a metallocycle ring, or two Xs are joined to form a chelating ligand, a diene ligand, or an alkylidene ligand;
• and (3) each R2-R7 is independently hydrogen, C1-C50 substituted or unsubstituted hydrocarbyl, or C1-C50 substituted or unsubstituted halocarbyl, provided that any one or more of the pairs R4 and R5, R5 and R6, and R6 and R7 may be bonded together to form a saturated or partially saturated cyclic or fused ring structure;
• (b) controlling the polymerization reaction so as to obtain a copolymer composition having Mooney viscosity within the range from 30 to 40 MU (MST, 5+4 @ 200° C.) and comprising units derived from the first C2-C20 α-olefin monomer, the second C2-C20 α-olefin monomer, and optionally the one or more dienes;
• and
• (c) controlling the polymerization such that the copolymer composition has Mooney Relaxation Area (MSTRA) within the range from 350 to 550 MU-sec,
• wherein the controlling (c) is based at least in part upon the molar ratio of the first metallocene catalyst to the second metallocene catalyst in the polymerization reaction.