| abstract |
The present application relates to copolymer compositions and copolymerization processes, as well as lubricating oil compositions comprising such copolymer compositions as viscosity index improvers, and base oils. The copolymer composition can be prepared using two different metallocene catalysts: a metallocene catalyst is capable of producing high molecular weight copolymers; and a metallocene catalyst is suitable for preparing low molecular weight copolymers having at least a portion of the vinyl terminations, and copolymer compositions prepared therefrom. The copolymer composition may comprise (1) a first ethylene copolymer fraction having a high molecular weight, exhibiting a branched topology, and having a lower ethylene content (based on the weight of the first ethylene copolymer fraction); and (2) a second ethylene copolymer fraction having a low molecular weight, exhibiting linear rheology, and having a higher ethylene content (based on the weight of the second ethylene copolymer fraction). Lubricating oil compositions comprising such copolymer compositions may exhibit excellent viscosity properties. |