POLYMER DISPERSING AGENT

摘要

The invention provides a polyolefin-derived copolymer obtainable by a process which comprises reacting: (i) a mixture of (a) a polyolefin or succinic anhydride derivative thereof, and (b) a polyamine having terminal -NH2 groups, or (ii) the reaction product of (a) and (b); with carbon monoxide, hydrogen and a diene; in the presence of a suitable solvent and a catalyst system comprising a source of cationic rhodium; optionally a source of cationic ruthenium; an aromatic N-heterocyclic ligand; and a source of an anion other than a halide; a process for preparing the copolymer; and lubricating oil and fuel compositions containing the copolymer.