Blocky Ethylene Propylene Copolymers and Methods for Making Them

A process for preparing a copolymer comprising:

• polymerizing propylene and ethylene in a solution process and in the presence of a catalyst system comprising a catalyst and an activator;
• a. wherein the catalyst comprises a metallocene compound;
• b. wherein the activator comprises a cationic component and an anionic component;
• c. wherein the cationic component of the activator corresponds to the formula:
• i. [R1R2R3NH]+, where R1 and R2 are together a —(CH2)a— group, where a is 3, 4, 5, or 6 and R1 and R2 form a 4-, 5-, 6-, or 7-membered non-aromatic ring together with the nitrogen atom to which one or more aromatic or heteroaromatic rings may optionally be fused via adjacent ring carbon atoms;
• and R3 is a C1-C5 alkyl group;
• or
• ii. [R3NH]+, where all R are identical and are C1-C3 alkyl groups;
• and
• d. wherein the anionic component of the activator corresponds to the formula [B(R4)4]−, where R4 is an aryl group or a substituted aryl group having one or more substituents, wherein the one or more substituents are identical or different and are selected from alkyl, aryl, halogenated aryl, or haloalkylaryl groups or a hydrogen atom.