| 摘要 |
Ethylene copolymers derived from about 2 to 98 wt. % ethylene, and one or more C3 to C28 alpha olefins, e.g. ethylene-propylene, are solution-grafted under an inert atmosphere and at elevated temperatures with an ethylenically-unsaturated carboxylic acid material in the presence of a high-temperature decomposable free-radical initiator and thereafter reacted with a polyfunctional material reactive with carboxy groups; such as (a) a polyamine, or (b) a polyol, or (c) a hydroxyamine, or mixtures thereof, to form carboxyl-grafted polymeric derivatives, which have good engine sludge and varnish control behavior in fuels and lubricating oils. If the molecular weight is above 10,000, then these polymers are also useful as multifunctional viscosity index improvers. |
