| abstract |
The novel highly grafted multifunctional olefin copolymers have a degree of grafting by reacting an acylating agent with an olefin copolymer having a number average molecular weight greater than about 1,000 in an extruder in the presence of free radical initiators and essentially free of hydrocarbon solvents ( DOG) is provided containing an additive reaction product by a process comprising the step of providing an olefin copolymer intermediate containing an acylated olefin copolymer having a weight of at least 0.5% by weight, the molecular weight of the copolymer intermediate is reduced, unreacted The component is vacuum stripped, pelletized, dissolved in neutral oil (preferably with an inert gas sparged) and further reacted with the polyamine to be grafted to the polyfunctional olefin copolymer viscosity modifier, and Lubricant concentrates and compositions containing them and their use are provided.n n n n Lubricating composition |