| abstract |
A novel highly grafted, multi-functional olefin polymer is provided comprising additive composition prepared by the steps comprising: (A) reacting an olefin copolymer of ethylene and at least one C3 to C23 α-olefin and, optionally, a polyene selected from non-conjugated dienes and trienes comprising from about 15 to 80 mole percent of ethylene from about 20 to 85 mole percent of said C3 to C23 α-olefin and from about 0 to 10 mole percent of said polyene, said copolymer having a number average molecular weight ranging from 1,000 to 500,000, with an olefinic carboxylic acid acylating agent, said process comprising heating said polymer to a molten condition at a temperature in the range of 60°C to 240°C, grafting in an extruder or a mixing device, said olefinic carboxylic acylating agent onto said copolymer, optionally subsequently reducing the molecular weight of said copolymer at a temperature in the range of 250°C to 350°C, thereby producing a grafted, reduced molecular weight acylated copolymer having a number average molecular weight ranging from 1,000 to 80,000 and having at least 1.0 molecules of said carboxylic acid acylating agent grafted onto each molecule of said olefin copolymer, and (B) reacting said acylated reduced copolymer in (A) with a specific polyamine. |