| 摘要 |
Oil-soluble, derivatized ethylene copolymers derived from about 2 to 98 wt. % ethylene, and one or more C3 to C28 alpha-olefins, e.g. propylene, which are grafted, preferably solution-grafted under an inert atmosphere and at elevated temperatures and in the presence of a high-temperature decomposable free-radical initiator, with an ethylenically-unsaturated carboxylic acid material and thereafter reacted with a polyfunctional material reactive with carboxy groups; such as (a) a polyamine, or (b) a polyol, or (c) a hydroxy amine, or mixtures thereof to form carboxyl-grafted polymeric derivatives are reacted with oil-soluble hydrocarbyl substituted acids, preferably with long chain alkyl aryl sulfonic acids with an average side chain carbon number of about 20-40, to yield haze-free hydrocarbon solutions, e.g. a lubricant additives composition, of increased dispersant potency. Useful number average molecular weight (Mn) of said copolymers range from about 700 to 500,000, however, if the molecular weight is from 10,000 to 500,000 then these copolymers are also useful as multifunctional viscosity index improvers. |
